An exhaust gas purification filter includes a plurality of cells each extending from an inflow end face to an outflow end face, a porous partition wall forming the cells in a partitioned manner, inflow-side sealing parts sealing openings on an inflow end face side of outflow cells where the exhaust gas flows out, and outflow-side sealing parts sealing openings on an outflow end face side of inflow cells where the exhaust gas flows in. Each of the inflow-side sealing parts has a porosity of less than 60%. The partition wall has a porosity of 60% or more and 70% or less. Assuming a pore size, at which cumulative pore volume is 50% in pore size distribution of the inflow-side sealing parts, is d50.sub.Pin, and a pore size, at which cumulative pore volume is 50% in pore size distribution of the partition wall, is d50.sub.B, the pore size d50.sub.Pin is less than 18 μm, and the pore size d50.sub.B is 18 μm or more and 25 μm or less.

The disclosure generally relates to filters, methods, and systems for filtering particulates from the exhaust of internal combustion engines such as gasoline direct injection engines and methods of preparing particulate filters.

A filter includes a filter medium having an average pore size of 1 to 5 mm, and photocatalyst particles deposited on the filter medium. The photocatalyst particle contains a titanium compound particle and a metal compound bonded to the surface of the titanium compound particle with an oxygen atom. The metal compound contains a metal atom and a hydrocarbon group. The titanium compound particle has absorption at wavelengths of 450 nm and 750 nm in the visible absorption spectrum of the titanium compound particle.

Air filters, and air filter devices for use in helicopters, and methods of use, are disclosed.

An exhaust gas purification filter includes a plurality of cells each extending from an inflow end face to an outflow end face, a porous partition wall forming the cells in a partitioned manner, inflow-side sealing parts sealing openings on an inflow end face side of outflow cells where the exhaust gas flows out, and outflow-side sealing parts sealing openings on an outflow end face side of inflow cells where the exhaust gas flows in. Each of the inflow-side sealing parts has a porosity of less than 60%. The partition wall has a porosity of 60% or more and 70% or less. Assuming a pore size, at which cumulative pore volume is 50% in pore size distribution of the inflow-side sealing parts, is d50.sub.Pin, and a pore size, at which cumulative pore volume is 50% in pore size distribution of the partition wall, is d50.sub.B, the pore size d50.sub.Pin is less than 18 m, and the pore size d50.sub.B is 18 m or more and 25 m or less.

The electret-treated sheet includes: a core layer (A) which is a porous film containing at least a thermoplastic resin; a surface layer (X) disposed on one side of the core layer (A); and a back surface layer (Y) disposed on the other side of the core layer (A), the surface layer (X) and the back surface layer (Y) each having a charged outermost surface, wherein the electret-treated sheet has a water vapor permeability coefficient of 0.1 to 2.5 g.Math.mm/m.sup.2.Math.24 hr; the core layer (A) has a pore aspect ratio of 5 to 50 and an average pore height of 2.5 to 15 m; the surface layer (X) and the back surface layer (Y) each have a thickness of 5 to 200 m; and the surface layer (X) includes a heat seal layer (B) including the outermost surface, wherein the heat seal layer (B) has a melting point of 50 to 140 C.

Gasoline Direct Injection (GDI) engines require gasoline particulate filters (GPFs) as a key component of the emissions control system to reduce particulate emissions. GPFs are known to have poor initial performance, with performance increasing after the filter develops a cake. This poor initial performance make it impossible to accurately assess vehicle emissions performance at the mileage requirements for vehicle certification. Compositions and methods are disclosed to improve filtration efficiency in a fresh or low mileage GPF.

A dirt separator for a vacuum cleaner including a chamber having an inlet through which dirt-laden fluid enters the chamber and an outlet through which cleansed fluid exits the chamber; and a disc located at the outlet, the disc being arranged to rotate about a rotational axis and including holes through which the cleansed fluid passes. The disc includes a first region in which a first array of said holes is provided, and a second region, radially outward of the first region, in which a second array of said holes is provided. Each hole of the second array has a larger cross-sectional area than each hole of the first array.

Gasoline Direct Injection (GDI) engines require gasoline particulate filters (GPFs) as a key component of the emissions control system to reduce particulate emissions. GPFs are known to have poor initial performance, with performance increasing after the filter develops a cake. This poor initial performance make it impossible to accurately assess vehicle emissions performance at the mileage requirements for vehicle certification. Compositions and methods are disclosed to improve filtration efficiency in a fresh or low mileage GPF.

The invention provides a composite ceramic filter material for high temperature flue gas dust removal, wherein the filter material is prepared by the following method: provide corn stalk raw material and silicon powder; crush the corn stalk raw material and pyrolyze the crushed corn stalk raw material to obtain carbonized corn stalks; spread silicon powders on, the corn stalk raw material to obtain mixed powder, perform first high-temperature heat treatment on the mixed powder to obtain silicon carbide powder; add silicon carbide powder into ethanol; add PVB to the ethanol suspension of silicon carbide to obtain a dispersion solution of silicon carbide; perform surface treatment on the aluminum alloy base material; porous silicon carbide film is formed on the surface of the surface treated aluminum alloy by air spraying technology; perform pre-sintering on the porous silicon carbide film; perform sintering on the pre-sintered porous silicon carbide film.