Abstract: A porous absorbent made of a filter, a filter material or a sponge material is inserted into a polluted part of soil or groundwater containing environmental pollutants such as chlorinated solvents or heavy metal ions. The porous absorbent is inserted into the polluted environment such that its one end comes into contact with the pollutants and the other end is exposed to air. The porous absorbent allows the pollutants absorbed thereby to rise up to its air-exposed end through the vaporizing activity of the pollutant themselves and of the water containing them. The pollutants are allowed to evaporate from the air-exposed end to be dissipated into the air, or to concentrate at the air-exposed end for later removal. Further, microorganisms fixed to the porous absorbent are used to decompose pollutants for removal, or to absorb pollutants for removal. Those pollutant eliminating methods allow efficient elimination of even highly concentrated pollutants at a low cost without requiring complicated processes.

Abstract: A sample introducing apparatus for an inductively coupled plasma mass spectrometer comprises a means supplying the inert gas for carrying the vaporized sample, a heater for defining the path through which the inert gas is passed as well as having the inner surface, on which the sample to be analyzed thereon is put and for generating the heat with the electrical being applied, in which the film structure is formed on said surface, and the surface contacted with the inert gas of the film structure vaporized the sample made of any one of the high melting metal oxide and the high melting metal nitride, an electrode structure for supporting the heater and supplying the electrical power to the heater.

Abstract: The resolution device for semiconductor films according to the present invention comprises a sealed container, a storage container installed in the sealed container for storing hydrofluoric acid to generate hydrogen fluoride gas, a semiconductor film supporter installed in the sealed container, and a receptacle of resolved solution installed at the bottom of the sealed container for receiving the resolved solution of the semiconductor films. The semiconductor films held by the film supporter are resolved by hydrogen fluoride gas which is generated from the storage container of hydrofluoric acid and has a low impurity content. The resolved solution is collected in the receptacle for resolved solution, and is supplied directly to the flameless atomic absorption spectrophotometer.

Abstract: Disclosed is method of recovering tantalum from silicon-containing tantalum scrap, which comprises dissolving said scrap in an inorganic acid, bringing the resulting solution into contact with an anionic exchange resin, followed by washing said anionic exchange resin with (a) a solution of 3 to 10 mol/l. of hydrofluoric acid or (b) a solution of strongly acidic medium containing 0.01 to 0.5 mol/l. of hydrofluoric acid and 1 to 6 mol/l. of a strong acid, and then washing the same with an aqueous solution of a mixture composed of hydrofluoric acid, aqueous ammonia and an ammonium salt.

Abstract: Barium-ferrite series powders are prepared from an alkaline aqueous solution containing a prescribed ratio of ions of the metals equal to those contained in the powder. In the first stage, the alkaline aqueous solution is heated at a constant volume at 150.degree. to 300.degree. C. to precipitate a precursor of the barium-ferrite series powder. Then, the precursor is baked at 700.degree. to 1,000.degree. C. to crystallize the precursor.