An exhaust gas purifying system for an engine includes a three-way catalyst, a particulate filter, an ammonia sorbent unit, an exhaust gas purifying catalyst unit, and a gas injection component including an oxygen-containing gas, all coupled to an exhaust line. Methods for purifying exhaust gas from an engine include exposing the exhaust gas to a three-way catalyst and a particulate filter, thus generating ammonia. The ammonia may be stored in an ammonia sorbent unit during a cold start condition. An oxygen-containing gas may be injected into the exhaust line. Once the ammonia sorbent has reached a desorption temperature, the ammonia may be released into the exhaust line and exposed to an exhaust gas purifying catalyst unit. The exhaust gas purifying catalyst partially oxidizes the ammonia to nitrous oxides (NOx) and subsequently catalyzes a reaction between the remaining ammonia and the nitrous oxides to give nitrogen gas and water.

An air conditioning and filtration system (10) comprising a pre-treatment system (12) for initially filtering air drawn from an external environment; pressurisation means (50) for positively pressurising air filtered by the pre-treatment system (12) and at least one circulation means (106). Each circulation means (106) draws air from the external environment through the pre-treatment system (12) and pressurisation means (50) as well as air from at least one enclosed area (1) for combination into an air stream. The air stream is thereafter directed to at least one set of filtration means (94) and air conditioning means (96) before being conveyed to at least one of the at least one enclosed areas (1).

The plugged honeycomb structure includes a plurality of honeycomb segments, a bonding layer, and plugging portions which plug open ends of cells of each honeycomb segment, and in the honeycomb segment, at least two types of cells having different sectional shapes are formed to constitute predetermined repeated arrangement patterns, and in rim circumferential wall cells including rims of the cells surrounded with partition walls and segment circumferential walls, an inflow open area of each corner rim circumferential wall cell disposed in each corner portion of the honeycomb segment is 1.1 times or more as large as an average inflow open area of non-corner rim circumferential wall cells arranged in portions other than the corner portions, or an outflow open area of the corner rim circumferential wall cell is 1.1 times or more as large as an average outflow open area of the non-corner rim circumferential wall cells.

Provided are filtration devices, including medical filtration devices, for operating within a vacuum unit. The filtration system removes particulate matter, including smoke, volatile compounds, and long chain organic compounds. The construction of the filtration system is within a single filter housing allowing for ease of construction and a single potting versus multiple potting's. The filtration system contains a hermetic seal to achieve a lower probability of seal failure versus processes that require multiple potting's.

The plugged honeycomb structure includes a plurality of honeycomb segments, a bonding layer, and plugging portions which plug open ends of cells of each honeycomb segment, and in the honeycomb segment, at least two types of cells having different sectional shapes are formed to constitute predetermined repeated arrangement patterns, and in rim circumferential wall cells including rims of the cells surrounded with partition walls and segment circumferential walls, an inflow open area of each corner rim circumferential wall cell disposed in each corner portion of the honeycomb segment is 1.1 times or more as large as an average inflow open area of non-corner rim circumferential wall cells arranged in portions other than the corner portions, or an outflow open area of the corner rim circumferential wall cell is 1.1 times or more as large as an average outflow open area of the non-corner rim circumferential wall cells.