Abstract: A nucleating agent for NaOH/H.sub.2 O solutions comprises a metal bar, magnetic tape adhered to a surface area of the bar and particulate magnetite on the surface of the tape. The magnetic field created by the tape holds the bar, tape and magnetite in fixed relation to each other.

Abstract: A process is disclosed for removing contaminants from impure alkali metal nitrates containing them. The process comprises heating the impure alkali metal nitrates in solution form or molten form at a temperature and for a time sufficient to effect precipitation of solid impurities and separating the solid impurities from the resulting purified alkali metal nitrates. The resulting purified alkali metal nitrates in solution form may be heated to evaporate water therefrom to produce purified molten alkali metal nitrates suitable for use as a heat transfer medium. If desired, the purified molten form may be granulated and cooled to form discrete solid particles of purified alkali metal nitrates.

Abstract: A process is provided wherein metal granules coated with a polymerizable oil are heated, while being mechanically mixed, to a polymerizing temperature to convert the oil coating to a varnish and the varnish coating thereafter heated to a higher temperature to decompose at least partially the varnish to carbon, thereby producing a carbon coating strongly bonded to the metal granules. The temperatures employed are below the melting point of the metal granules. The coating is preferably applied to magnesium, aluminum or alloys thereof for use as addition agents in steel, e.g., desulfurizing or deoxidizing agents, and may contain fine particles of at least one calcium compound.

Abstract: A method for processing a sulfidic zinc source to recover metallic zinc wherein the source is leached with an electrolysis cell acid, the leaching product is separated into a liquor and a primary leaching residue, followed by drying and smelting of the dried leaching residue. The improvements of the present invention are directed primarily to the treatment of the liquor recovered from the leaching stage, and involve crystallizing out Fe.sup.2+ from the liquor as a ferrous sulfate hydrate in a crystallization stage, separating the filtrate from the crystallization stage in a first separation stage to produce a filtrate and a residue, neutralizing and oxidizing the separated filtrate from the crystallization stage to precipitate the remaining Fe.sup.2+ in a precipitation stage, separating the filtrate from the precipitation stage in a second separation stage and purifying the separated filtrate from the second separation stage before passing it to the electrolysis cell.

Abstract: Phosphosiderite, FePO.sub.4.2H.sub.2 O, is prepared in high yield from molten Fe(NO.sub.3).sub.3.9H.sub.2 O and H.sub.3 PO.sub.4 using a phosphosiderite seed for initiation of precipitation and crystallization.

Abstract: In the manufacture of iron oxide flakes by the steps of mixing an aqueous ferric salt solution with an aqueous alkali solution for thereby inducing an amorphous precipitate and subjecting the precipitate to a hydrothermal treatment, iron oxide flakes of an increased flake size are obtained by adding boric acid or a salt thereof to the mixture prior to the step of hydrothermal treatment.

Abstract: Single crystalline, acicular ferric oxide particles are produced by maintaining an aqueous suspension of ferric hydroxide at an elevated temperature at an alkaline pH in the presence of an organic phosphonic acid compound or a hydroxycarboxylic acid compound as a growth-regulating agent.

Abstract: Concentrated sulphuric acid aqueous solutions, stably clear through the time, are obtained starting from diluted sulphuric acid aqueous solutions containing Mg and possibly other impurities such as Fe, Al, Cr, V and Mn, by evaporation concentration. The process is characterized in that, before filtering, the slurry obtained by evaporation concentration, is cooled down to 10.degree.-25.degree. C. and maintained at this temperature for not less than 12 hours.

Abstract: Single crystalline, ferrite particles are obtained by the thermal reaction of ferric oxyhydroxide, ferric hydroxide, porous ferric oxide made therefrom or ferric oxide having a particle size less than 0.8.mu. with a strontium or barium compound such as the oxide, hydroxide, the carbonate or the carboxylate in the presence of a small amount of a metal chloride flux such as strontium chloride or barium chloride.The resulting particles have a well-defined, hexagonal plate configuration and are particularly adapted for the production of anisotropic magnets.

Abstract: Metal hydroxides such as Fe(OH).sub.2, Fe(OH).sub.3 and Sn(OH).sub.2 are prepared in the form of spherical particles of uniform and controlled size suitable for tagging with a radioactive element such as technetium-99m. Aqueous suspensions of such tagged particles are useful in scintigraphy as lung scanning agents.

Abstract: A method of making nickel zinc ferrite by liquid-phase epitaxial growth at constant temperature ferrite thin films having desired magnetic properties can easily be formed by preparing the metal oxide melt components from which the ferrite thin films are epitaxially crystallized. The ferrite thin films are suitable for various electronic parts.

Abstract: A process for the production of high purity iron sulfate monohydrate from an iron sulfide mineral feed involving a leaching, purification, crystallization and dehydration procedure to recover a solution of iron sulfate containing iron sulfate polyhydrates and to convert iron sulfate polyhydrates in a series of steps to monohydrate crystals. The process can be also advantageously used with iron sulfide feed materials containing non-ferrous metals with full separation and recovery of the non-ferrous metals in the sulfide residue of the leaching and purification process of this invention. It can also be used for the purification of industrial pickle liquor solutions which can be treated with the iron sulfide mineral feed in this process leach circuit with full recovery of the ferrous and non-ferrous metals content of these solutions.