Abstract: In the flux method, a source nitrogen gas is sufficiently heated before feeding to an Na—Ga mixture. The apparatus of the invention is provided for producing a group III nitride based compound semiconductor The apparatus includes a reactor which maintains a group III metal and a metal differing from the group III metal in a molten state, a heating apparatus for heating the reactor, an outer vessel for accommodating the reactor and the heating apparatus, and a feed pipe for feeding a gas containing at least nitrogen from the outside of the outer vessel into the reactor. The feed pipe has a zone for being heated together with the reactor by means of the heating apparatus, wherein the zone is heated inside the outer vessel and outside the reactor.

Abstract: An object of the invention is to prevent, in the flux method, diffusion of substances that constitute the atmosphere of the outer vessel into the reactor. The apparatus for producing a group III nitride based compound semiconductor, the apparatus including a reactor which maintains a group III metal and a metal differing from the group III metal in a molten state, a heating apparatus for heating the reactor, and an outer vessel for accommodating the reactor and the heating apparatus, characterized in that diffusion of substances that constitute the atmosphere of the outer vessel into the reactor is prevented.

Abstract: A growth apparatus is used having a plurality of crucibles 10 each for containing the solution, a heating element for heating the crucible, and a pressure vessel for containing at least the crucibles and the heating element and for filling an atmosphere comprising at least nitrogen gas. One seed crystal is put in each of the crucibles to grow the nitride single crystal on the seed crystal.

Abstract: It is disclosed an apparatus for growing a nitride single crystal using a flux containing an easily oxidizable substance. The apparatus has a crucible for storing the flux; a pressure vessel for storing the crucible and charging an atmosphere containing at least nitrogen gas; furnace materials disposed within the pressure vessel and out of the crucible; heaters attached to the furnace material; and alkali-resistant and heat-resistant metallic layers covering the furnace material.

Abstract: In a method of growing a single crystal by melting a raw material within a vessel under a nitrogenous and non-oxidizing atmosphere, the vessel is oscillated and the melted raw material is contacted with an agitation medium made of a solid unreactive with the melted raw material.

Abstract: The apparatus has a crucible for storing a solution; an inner container 16 for storing a crucible; a heating container 31 for storing the inner container 16, the heating container 31 including heating elements 14, a container body 13 provided with the heating elements 14 and a lid 12 combined with the container body 13; and a pressure vessel 30 for storing the heating container 31 and for charging an atmosphere comprising at least nitrogen gas. The lid 12 has a fitting surface 12b to the container body inclined to a horizontal plane P.

Abstract: A ceramic filter has a porous body (2) and filtration membranes (5). The porous body (2) has main flow paths (3) for fluid to be purified which extend from one end face (4a) to the other end face (4b) of the body. The filtration membranes (5) are arranged on the inner wall surfaces of the main flow paths (3). The fluid to be purified that flows into the filter from first opening portions (11) of the main flow paths (3) is purified by permeating it inside the porous body (2). The fluid is then taken out as purified fluid from an outer peripheral surface (6) of the porous body (2). The ceramic filter is characterized in that the diameters of the main flow paths (3) in a cross section perpendicular to a flowing direction of the fluid to be purified are gradually reduced from opening diameters (a1, a2, a3) of the first opening portions (11) to opening diameters (b1, b2, b3) of second opening portions (12). The structure enables easy removal of a deposit on the filter by counter flow washing.

Abstract: A ceramic filter includes: a porous body (2) having a plurality of main flow paths (3) extending from one end face (4a) to the other end face (4b) of the body, and filtration membranes (5) arranged on the inner wall surfaces of the main flow paths (3). Slit-shaped auxiliary flow paths (9) are formed in predetermined portions so that specific main flow paths (3a) are communicated with an external space. Openings of the specific flow paths (3a) at both end faces (4a, 4b) are sealed. Fluid to be purified that flows into the filter from first opening portions (11) of the main flow paths (3) is purified by permeating it inside the porous body (2). The fluid is then taken out as purified fluid from an outer peripheral surface (6) of the porous body (2) and exits (10) of the auxiliary flow paths (9).

Abstract: A method of manufacturing an enhanced porous ceramic article includes the steps of: impregnating (a) a porous ceramic body, (b) a first porous body having one or more dried layers of porous ceramic films on a surface of a porous ceramic body, or (c) a second porous body having one or more dried-fired layers of porous ceramic films on a surface of a porous ceramic body, with inorganic oxide sol; sending air to a desired portion of the porous ceramic body and/or the porous ceramic films to aggregating and drying inorganic oxide particles in the inorganic oxide sol inside a surface of the desired portion; and thereafter firing the body or the body with the film to obtain the enhanced porous ceramic article. The manufacturing method is capable of substantially uniformly aggregating and supporting inorganic oxide such as silica in a desired portion of the porous ceramic article for use in a ceramic filter or the like.