Abstract: A process for the production of pure magnesium chloride liquor from siliceous magnesium minerals comprises the steps of continuously leaching the siliceous magnesium mineral with a hydrochloric acid solution at a temperature higher than 50.degree. C. but below the boiling point and in such a manner as to maintain the pH of the slurry below 1.5 to prevent the formation of silica gel, continuously reacting such slurry with a reactive magnesia in order to raise the pH to 4.0-7.0 to precipitate substantially all the impurities from solution while preventing silica gel formation, and performing a solid/liquid separation of the slurry on suitable filtration equipment to obtain pure magnesium chloride liquor.

Abstract: Commercially valuable chemicals are extracted from tire-derived pyrolytic oils by subjecting the pyrolytic oils to a fractional distillation at a temperature of up to about 204.degree. C. under atmospheric pressure to isolate at least one commercially valuable chemical selected from the group consisting of paraffins, naphthenes, olefins and aromatics. Particularly valuable chemicals which can be extracted from tire-derived pyrolytic oils are benene, toluene, xylene, styrene and limonene-dl. The distillation fraction boiling above 204.degree. C. can be used as an extension oil in the manufacture of various rubber and plastic parts. Also disclosed is an improved process for producing carbon black by vacuum pyrolysis of used rubber tires.

Abstract: A ferrofluid composition is defined by fine particles of ferromagnetic material, a liquid carrier for dispersing the ferromagnetic material and a surfactant or surfactants acting as a dispersant. The surfactant is required to have such relation to the carrier that the surfactant has, as its hydrophobic group portion, a structure equivalent to the carrier, and the carrier is selected to be either an alkylpolyphenyl ether oil, an alkylnaphthalene oil or both. By virtue of this structural feature, fine ferromagnetic particles are uniformly and stably dispersed throughout the carrier which has low viscosity and is thermally very stable.

Abstract: Thin films of boron nitride are grown on single crystal silicon substrates using laser deposition techniques. The films are characterized by essentially a single crystal throughout and having a cubic structure which is in epitaxial registry with the underlying silicon substrate.

Abstract: A process for producing a dawsonite with a short-prismatic, isometric crystal habit. The dawsonite can be produced without occupational medicine concerns and can be used as, among other things, a flame-retardant additive in plastics.

Abstract: The present invention provides a stabilized concentrated sulphuric acid composition containing a chemical additive selected from a group of aminoalkylphosphonates that increases the precipitation threshold of impurities in solution, thereby suppressing the precipitation of said impurities and the formation of "cloudy acid".

Abstract: A crystal pulling method includes the steps of disposing a separation wall concentrically with an in a semiconductor crystal pulling crucible to divide the crucible into an inner chamber and an outer chamber, putting first doped material melt into the inner chamber and second material melt into the outer chamber, and pulling crystal from the first material melt in the inner chamber while the second material melt in the outer chamber is being supplied to the inner chamber via a coupling member which connects the inner and outer chamber with each other but suppresses the outflow of impurity from the inner chamber to the outer chamber. Assume that k is the segregation coefficient of doping impurity in the first material melt, r is half the inner diameter of the inner chamber, and R is half the inner diameter of the outer chamber. The second material melt in the outer chamber is undoped melt, and the condition of (r/R)>.sqroot.

Abstract: Disclosed is a process for preparing crystals of anhydrous sodium sulfide, the process being characterized in that the process comprises the steps of heating a water-containing non-crystalline sodium sulfide at a temperature of about 30.degree. to about 89.degree. C. under a pressure of about 500 torr or less for about 2 hours or longer in a first-stage heating step and further heating the sodium sulfide at a temperature of about 90.degree. to about 200.degree. C. under atmospheric pressure or reduced pressure for about 2 hours or longer in a second-stage heating step.

Abstract: A superparamagnetic fluid having a non-polar hydrocarbon oil carrier liquid and coated magnetic particles coated with at least one acid selected from the group consisting of an organic acid containing only carbon and hydrogen atoms in the chain connected to the carboxyl group, wherein the chain contains at least 19 carbon atoms, and an amino acid acylated with a fatty acid, provided that said organic and amino acids are branched, unsaturated, or both.A method of making a superparamagnetic fluid, including providing an aqueous suspension of coated magnetic particles coated with at least one acid selected from the group consisting of an organic acid containing only carbon and hydrogen atoms in the chain connected to the carboxyl group, wherein the chain contains at least 19 carbon atoms, and an amino acid acylated with a fatty acid, provided that said orgaic and amino acids are branched, unsaturated, or both.

Abstract: A mixture comprising (i) an oxide, hydroxide or oxyhydroxide of aluminum, (ii) an aluminum-containing sulfate, (iii) an oxide or oxyacid of boron or an alkali metal salt thereof and (iv) an alkali metal sulfate is heated at a temperature of 900 to 1200.degree. C. to grow an aluminum borate whisker. In this process, the reaction is advanced apparently in the solid phase, and this process is advantageous over the conventional processes in that the yield is high and the isolation and purification of the reaction product is facilitated.

Abstract: An aluminum borate whisker is prepared by heating and reacting aluminum sulfate and an oxide of boron, an oxyacid of boron or an alkali metal salt thereof in the presence of an alkali metal sulfate and an alkali metal carbonate. In this process, the reaction is advanced apparently in the solid phase, and this process is advantageous over the conventional processes in that the yield is high and the withdrawal of the reaction product is facilitated.

Abstract: A process for the production of boron nitride is carried out by condensing a mixture of a B-tris-(loweralkylamino)borazine with an alkylamine in an inert gas atmosphere at a temperature of 150.degree. C. or above to prepare a precursor, forming the precursor into a desired shape and then slowly heating the shaped precursor in an ammonia gas atmosphere until the precursor changes to a white boron nitride product.The shaped boron nitride in a form of fiber is particularly useful as a reinforcement.

Abstract: A high temperature absorption process for bulk recovery of CO.sub.2 comprises contacting a gaseous mixture containing CO.sub.2, H.sub.2 S, and natural gas with C.sub.3 and heavier components and having a high and variable CO.sub.2 loading, with an amine absorbent solution at a temperature above 220.degree. F. The amine absorbent solution is continuously regenerated in a multiple section flashing so as to reduce the energy requirements for regeneration and thereby making the process more suitable for bulk recovery of CO.sub.2 from gas streams associated with enhanced oil recovery projects employing CO.sub.2 for miscible flood of oil reservoirs.

Abstract: A method is described for the creation of novel q-effect cadmium sulfide membranes. The membranes are made by first creating a dilute cadmium sulfide colloid in aqueous suspension and then removing the water and excess salts therefrom. The cadmium sulfide membrane thus produced is luminescent at room temperature and may have application in laser fabrication.

Abstract: A novel, multi-element metal chalcogenide is disclosed which has the following general formula (I):X.sub.(1-a)x X'.sub.ax Y.sub.y Z.sub.z (I)wherein X stands for at least one element selected from Bi, Sb and As, X.sup.1 stands for at least one element selected from Pb, Sn and Ge, Y stands for at least one element selected from Ti, V, Nb and Ta, Z stands for at least one element selected from S, Se and Te, a is a number of 0-1, x is a number of 0.8-1.2, y is a number of 0.8-1.2 or 1.6-2.4 and z is a number of 2.4-3.6 when y is 0.8-1.2 or a numeral of 4.0-6.0 when y is 1.6-2.4.

Abstract: Vent gas from the condenser-scrubber system of a reactor, in which dithionites are made by reacting a formate, sulfur dioxide, and an alkali in aqueous methanol, is reduced in its ethylene oxide content to less than 10 ppm maintaining the ratio of sulfur dioxide to ethylene oxide entering the scrubber to greater than 1.0, preferably greater than 2.5, and most preferably greater than 3.0 and at a temperature of -20.degree. C. to 0.degree. C.

Abstract: Magnetizable microspheres, optionally in aqueous dispersion, consisting of a matrix of at least one organopolysiloxane optionally bearing Si-vinyl groups or reactive and/or ionic units and magnetizable particles less than 300 angstroms in diameter encapsulated in the matrix. The magnetizable microspheres are prepared by homogenizing a solution of the organopolysiloxane and a magnetic fluid in the presence of water and a surfactant, removing the solvent for the organopolysiloxane and the carrier liquid of the magnetic fluid, and at least partially removing the water. The magnetizable microspheres are useful in biological applications as active supports.

Abstract: A crystal pulling apparatus of double structure crucible has a crucible body which is divided into inner and outer chambers by a cylindrical partition wall coaxially disposed in the crucible body. A melt supplying path used to supply melt from the outer chamber of the crucible to the inner chamber in which the crystal is pulled is formed of a small through hole formed in the partition wall or the small through hole and a pipe-like passage formed in communication with small through hole. The radius of the inner chamber of the double structure crucible has a specified relation determined by the segregation coefficient of dopant impurity with respect to the radius of the outer chamber. This is, the radius of the inner chamber is set substantially equal to .sqroot.k times the radius of the outer chamber when the segregation coefficient of the dopant impurity is k.

Abstract: Contaminants in spent nitric-sulfuric nitration acid can be removed by mixing the spent acid with urea and heating to 75.degree.-150.degree. C. Off-gas from the spent acid/urea reaction is passed through a Group IB, VB, VIB or VIII metal containing catalyst to decompose nitrous oxides and the so-treated off-gas is contacted with spent acid, denitrated spent acid, or fresh sulfuric acid, and optionally air (i.e. oxygen), to absorb oxides of nitrogen. The spent acid scrubbing fluid is then subjected to the same process for removing contaminants.

Abstract: A three step annealing treatment for Hg.sub.1-x Cd.sub.x Te includes a high temperature anneal to reduce excess tellurium, followed by an intermediate temperature anneal to reduce the supersaturation of metal vacancies, and lastly a low temperature anneal to reduce metal vacancies; see FIG. 4. The intermediate anneal reduces the metal vacancy concentration sufficiently that microvoids do not form from condensation of metal vacancies in desired portions of the Hg.sub.1-x Cd.sub.x Te during the low temperature anneal. Alternate preferred embodiments include more than three steps and incremental cooling.