Abstract: A small, battery-powered air purifier can be clipped to a wearer's front shirt pocket or worn suspended from a cord about the wearer's neck. The device includes a housing containing a compact circuit that transforms direct current provided by the battery into a negative high voltage pulsating current which is connected to a sharp metal point contained within a chamber inside the hollow housing. A corona discharge forms on the sharp point, ionizing air molecules and any particulates, and generating ozone. An opening into the chamber is covered by a noncorrosive metal grid connected to the positive terminal of the battery. The negative ions are attracted to this grid, thereby completing an electrical circuit. Movement of the ions to the grid results in mass movement of air which causes a stream of air to emerge through the grid. As the air passes the grid, negatively charged particulates are deposited on the grid.

Abstract: An electric dust collector system which contains a plurality of charging mechanisms such as ionizer electrodes for charging dust particles and a plurality of collector mechanisms such as collector electrodes for collecting the dust particles. The collector electrodes are oxidized inwardly from the surface to form a metal oxide semiconductor layer. An ionizer-collector integrated electric dust collector system where the collector electrodes are extended and connected from the ionizer electrodes is disclosed. In a preferred embodiment, an electric dust collector system further contains electrostatic filters for collecting the dust particles and mesh-shaped electrodes for applying the electric field.

Abstract: An electrostatic precipitator assembly is disclosed. The assembly includes a tubular collector and an electrode suspended therein. The electrode includes a substantially cylindrical collector portion and a charging portion which includes a rod and a charging disk, wherein the gap between the charging disk and the collector is at least as great as the gap between the collector portion of the electrode and the collector.

Abstract: Filtration material comprising a web comprising meltblown fibers and staple, electrically charged fibers randomly dispersed among the meltblown fibers. The filtration material can be formed in planar configurations and in configurations other than planar. Non-planar configurations can extend the useful working area for a given filter element's cross-section without requiring an additional corrugating or pleating process step. The filtration material exhibits high strength and low pressure drop.

Abstract: The apparatus for dedusting a gas by electrostatic precipitation includes an advantageously steel housing and a plurality of discharge electrodes and collecting electrodes arranged in the housing. Each of the electrodes is made of a ceramic material and has an electrically conducting layer on at least one side thereof. The electrically conducting layer consists of a copper, nickel, bronze or iron-chromium-nickel alloy layer having a thickness of 0.1 to 2 mm. The ceramic material has a porosity of 25 to 90%, consists of fibers compacted with an inorganic binder and contains 30 to 70% by weight Al.sub.2 O.sub.3, 15 to 50% by weight SiO.sub.2 and 1 to 10% by weight of the inorganic binder. The discharge and collecting electrodes can be plates with a wall thickness of 5 to 100 mm. The discharge electrodes alternatively are tubular and have a wall thickness of 5 to 30 mm and a diameter of 30 to 100 mm.

Abstract: An improved hot-side electrostatic precipitator is provided which more efficiently removes particulates such as fly ash from gases by substantially decreasing the occurrence of back corona discharge. The improved hot-side electrostatic precipitator is based upon the discovery that back corona discharge occurs primarily, if not entirely, in the accumulated particle layer in those sections of the collection plates having a temperature low enough to initiate back corona discharge.

Abstract: A dust collector includes a front case and a rear case. A discharging electrode plate and an electrical charge plate are arranged zig-zag along guide elements formed in the front case, the guide elements extending in a front-to-rear direction. A dust collecting part is installed under the discharging electrode plate and the electrical charge electrode plate. An active carbon filter is installed in the rear case in order to deodorize the air.

Abstract: A photographic element is disclosed comprised of a support and, coated on the support, at least one radiation-sensitive layer. The radiation-sensitive layer contains silver halide grains including a spectral sensitizer adsorbed on the surface thereof and, intimately admixed therewith, silver halide grains free of surface spectral sensitization and having a particle size in the range of 0.15 to 0.8 micron in diameter. The photographic element exhibits improved speed without a concurrent increase in graininess.