Abstract: Disclosed is a process for the formation of silicon carbide powder in which vaporized polysiloxanes are reacted and pyrolyzed in a single heating step to form the silicon carbide powder. The process is simple and inexpensive and yields powder having desirable characteristics.

Abstract: A method of preparing ceramic materials or articles by the pyrolysis of preceramic silazane polymers, wherein the preceramic silazane polymers are rendered infusible prior to pyrolysis by treatment with steam or a steam and oxygen mixture, is disclosed. This method is especially suited for the preparation of ceramic fibers.

Abstract: A method of preparing ceramic materials or articles by the pyrolysis of preceramic silazane polymers, wherein the preceramic silazane polymers are rendered infusible prior to pyrolysis by treatment with steam or a steam and oxygen mixture, is disclosed. This method is especially suited for the preparation of ceramic fibers.

Abstract: A nose mask for administering one or more gases such as oxygen to a human being comprises, in combination, (I) a shell having a front portion, a rear portion and a first opening comprising substantially the entire horizontal area beneath the wearer's nose and (II) a hollow gas delivery tube containing at least one gas delivering and dispersing means. The mask enables a wearer to breathe, eat and converse in a substantially normal fashion while efficiently providing the wearer with a cloud of gas (enriched in the gas or gases being delivered) directly beneath the nose and in front of the mouth of the wearer. The mask is particularly useful in long-term oxygen therapy applications.

Abstract: A processable, stable, homogeneous blend is obtained by mechanically mixing a polydiorganosiloxane gum containing 0.2 to less than 1.5 mol percent silicon atoms having vinyl or allyl groups with an ethylene vinylacetate copolymer containing 8 to 35 weight percent copolymerized vinylacetate. The polymers are mixed at a shear rate greater than 10 sec.sup.-1, at a temperature between 170.degree. C. and 235.degree. C. and for a period of time sufficient to obtain at least 10 weight percent of the total blend of material which is insoluble in refluxing xylene.

Abstract: A solar energy collector is made up of a first flat flexible sheet preferably of silicone, and a first sinuous sheet also preferably of silicone, sealingly adhered to the first sheet along a plurality of spaced parallel lines to provide a series of substantially parallel ducts which carry a liquid heat transfer medium. Either the first flat sheet or first sinuous sheet incorporates solar energy absorbent material. A backing member which may include a sheet of reflective foil and a layer of foam insulation is adhered to the opposite side of the first sinuous sheet to form a plurality of substantially parallel air channels under the ducts. Desirably, a solar window which includes a second sinuous sheet with a second flat sheet adhered to the upper amplitudes thereof is adhered to the first flat sheet along the lower amplitudes to space the second flat sheet from the first flat sheet thereby providing a multiplicity of insulative air channels.

Abstract: This is an elastomeric safety insert for a pneumatic tire assembly. The insert when installed has a toroidal configuration and has protuberances extending therefrom to space the body portion of the insert from the rim and tire casing, permitting the insert to dynamically balance itself when the tire is rotated.