Abstract: Process for stabilizing particles of peroxygenated compounds by coating by means of a solid coating agent comprises applying a coating agent which contains at least one boron compound from metaboric acid, orthoboric acid and tetraboric acid.

Abstract: An SiO.sub.2 coated iron oxide powder used for the preparation of an acicular metallic iron powder or an acicular magnetic iron oxide powder, is produced by forming a slurry of hydrated iron oxide as a starting material or a iron oxide powder having pH of 8 to 14; admixing a water soluble silicate at a ratio of 0.1 to 10 mol % as SiO.sub.2 based on Fe; hydrothermally reacting said mixed slurry at 100.degree. to 250.degree. C. for 5 minutes or longer in a closed reactor, and washing, filtering and drying the product.

Abstract: Potassium ferrate (VI), K.sub.2 FeO.sub.4, which has been crystallized from a concentrated aqueous solution of KOH is washed with an aqueous solution of a potassium salt of an inorganic acid to remove the residual KOH. The wash solution is at an alkaline pH and contains a high concentration of the potassium salt.

Abstract: There is prepared pyrogenically produced silicon dioxide-mixed oxide having a BET surface area of 50 to 400 m.sup.2 /g which contains as a constituent of the mixed oxide:0.01 to 10 weight % zirconium dioxide or0.01 to 10 weight % iron oxide (ferric oxide) or0.01 to 9.9 weight % titanium dioxide.Because of the doping with the foreign oxide the silicon dioxide-mixed oxide is more temperature stable than the undoped silicon dioxide. The product can be used as thermal insulation either as unpressed material in free bulk form or as a compacted mixture.

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: A solution of an alkali metal inorganic salt in water, oil, and an emulsifier are agitated to form an emulsion. The water is removed from the emulsion which is then filtered. The filtrate is useful as an additive for controlling the structure of carbon black produced in the furnace process.

Abstract: An acrylic carbon fiber with excellent thermal oxidation resistance, which contains 50 ppm or more of a phosphorus component (as phosphorus) and/or a boron component (as boron) and which contains 100 ppm or more of a zinc component (as zinc) and/or a calcium component (as calcium), and which suffers a fiber weight reduction of about 20% or less upon standing for 3 hours in air at 500.degree. C.

Abstract: This invention relates to a process for preparing hydrophobic silicon dioxide which comprises treating silicon dioxide having a surface area of at least 50 m.sup.2 /g with an organosilicon compound containing from 2 to 4 silicon atoms per molecule, in which at least 2 hydrocarbon radicals are bonded to each silicon atom, and any silicon valences which are not satisfied by hydrocarbon radicals are satisfied by siloxane oxygen atoms and at least one tin compound containing Sn-bonded halogen and/or organic radicals.

Abstract: Sodium percarbonate is stabilized with highly dispersed silica. The sodium percarbonate containing 1 to 10 weight % of water is mixed with the silica and subsequently dried. The highly dispersed silica has an average particle size of 2-100 microns, preferably 7-20 microns. The product is sodium percarbonate particles encased by a sodium silicate jacket.

Abstract: Shaped silicon carbide ceramic articles of high density, e.g., at least 90 percent of theoretical, are produced by cold pressing and sintering boron-containing high purity, submicron beta silicon carbide powder. The silicon carbide powder is produced preferably by gas phase reaction of silicon halide, e.g., silicon tetrachloride, carbon source reactant, e.g., halogenated hydrocarbon, and boron source reactant, e.g., boron trichloride, with a hydrogen plasma.

Abstract: A sintered compact of boron nitride with high density form having high oxidation resistance, water resistance, compressive strength and hardness can be obtained by sintering wurtzite-structured boron nitride together with a boride of titanium, zirconium or hafnium, or with mixtures thereof under a condition of high temperature and high pressure.

Abstract: Stabilized crystalline sodium percarbonate is prepared by reacting a soda solution or suspension, which has a pH value of between 10 and 11 and contains an amount of a soluble silicate, e.g., sodium waterglass, which is equivalent to from about 0.2 to about 0.9% of SiO.sub.2 relative to the sodium percarbonate, with a hydrogen peroxide solution which contains a heavy metal complexing agent, allowing to crystallize at least 50% of the sodium percarbonate and then adding to the resulting suspension a second amount of a water soluble silicate which is equivalent to from about 0.2 to about 0.8% of SiO.sub.2 relative to the sodium percarbonate and is sufficient to provide a silicate content in the final product equivalent to 0.5 to 1.5% of SiO.sub.2.

Abstract: A stable hydrosulfite composition particularly useful for treating a dyed or tinted textile is provided by a homogeneous particulate admixture of a hydrosulfite, a pH builder salt and a pH buffer salt, and either detergent or stabilizer, or both.

Abstract: An aqueous hypochlorite solution containing a stabilizing amount of periodate ions, preferably an amount in the range 0.05 to 1000 parts per million (ppm) by weight based on the volume of the solution, the solution optionally containing silicate ions.

Abstract: Fine-grained polygonized halide alloy bodies are formed having comparable optical properties to a single crystal halide body. Heat and force are applied to a single crystal halide to recrystallize or polygonize the halide. Room temperature grain growth observed in fine-grained pure halides is inhibited by alloying.

Abstract: There is disclosed a process for increasing the output of high bulk density, hydrous sodium silicate which may be obtained by the spray drying of its aqueous solutions. This process involves the addition of certain additives to the aqueous sodium silicate solutions prior to their being spray dried.