Abstract: A silica-based substrate includes a glass phase and a dispersed phase having carbon, such that the silica-based substrate has a thickness of at least 10 gm. Also disclosed is a method of forming a silica-based substrate, the method including contacting a porous silica soot preform with an organic solution having at least one hydrocarbon precursor to form a doped silica soot preform and heating the doped silica soot preform in an inert atmosphere to form the silica-based substrate.

Abstract: A glass including silica and titania is disclosed. An average hydroxyl concentration of a plurality segments of the glass is in a range from about 20 ppm to about 450 ppm, an average titania concentration of the plurality of segments is in a range from about 6 wt. % to about 12 wt. %, and each segment of the plurality of segments has a length of about 12.7 mm, a width of about 12.7 mm, and a height of about 7.62 mm. The hydroxyl concentration of each segment is measured using a Fourier transform infrared spectroscopy in transmission, the refractive index is measured using an optical interferometer with a 633 nm operating wavelength and a resolution of 270 microns×270 microns pixel size, and the average titania concentration is determined based upon the measured refractive index.

Abstract: A method of melting glass and glass-ceramics that includes the steps: conveying a batch of raw materials into a submerged combustion melting apparatus, the melting apparatus having liquid-cooled walls and a floor; directing a flame into the batch of raw materials and the melted batch with sufficient energy to form the raw materials into the melted batch; and heating a delivery orifice assembly in the floor of the submerged melting apparatus to convey the melted batch through the orifice assembly into a containment vessel. The melted batch has a glass or glass-ceramic composition that is substantially reactive to a refractory material comprising one or more of silica, zirconia, alumina, platinum and platinum alloys.

Abstract: A method of melting glass and glass-ceramics that includes the steps: conveying a batch of raw materials into a submerged combustion melting apparatus, the melting apparatus having liquid-cooled walls and a floor; directing a flame into the batch of raw materials and the melted batch with sufficient energy to form the raw materials into the melted batch; and heating a delivery orifice assembly in the floor of the submerged melting apparatus to convey the melted batch through the orifice assembly into a containment vessel. The melted batch has a glass or glass-ceramic composition that is substantially reactive to a refractory material comprising one or more of silica, zirconia, alumina, platinum and platinum alloys.

Abstract: A method of melting glass and glass-ceramics that includes the steps: conveying a batch of raw materials into a submerged combustion melting apparatus, the melting apparatus having liquid-cooled walls and a floor; directing a flame into the batch of raw materials and the melted batch with sufficient energy to form the raw materials into the melted batch; and heating a delivery orifice assembly in the floor of the submerged melting apparatus to convey the melted batch through the orifice assembly into a containment vessel. The melted batch has a glass or glass-ceramic composition that is substantially reactive to a refractory material comprising one or more of silica, zirconia, alumina, platinum and platinum alloys.

Abstract: A method of capturing soot includes the steps: combusting a first precursor in a burner to produce a soot stream, the soot stream comprising soot and exiting the burner at an outlet; and directing a capture medium to the soot stream, the capture medium contacting the soot in an impact region, the soot having a temperature greater than 50° C. in the impact region.

Abstract: A silica-based substrate includes a glass phase and a dispersed phase having carbon, such that the silica-based substrate has a thickness of at least 10 gm. Also disclosed is a method of forming a silica-based substrate, the method including contacting a porous silica soot preform with an organic solution having at least one hydrocarbon precursor to form a doped silica soot preform and heating the doped silica soot preform in an inert atmosphere to form the silica-based substrate.

Abstract: One embodiment of the disclosure relates to a method of cleaning silica-based soot or an article made of silica-based soot, the method comprising the step of treating silica-based soot or the article made of silica-based soot with at least one of the following compounds: (i) a mixture of CO and Cl2 in a carrier gas such that the total concentration of CO and Cl2 in the mixture is greater than 10% (by volume, in carrier gas) and the ratio of CO:Cl2 is between 0.25 and 5; (ii) CCl4 in a carrier gas, such that concentration CCl4 is greater than 1% (by volume, in carrier gas). Preferably, the treatment by CCl4 is performed at temperatures between 600° C., and 850° C. Preferably, the treatment with the CO and Cl mixture is performed at temperatures between 900° C. and 1200° C. The carrier gas may be, for example, He, Ar, N2, or the combination thereof.

Abstract: A method of capturing soot includes the steps: combusting a first precursor in a burner to produce a soot stream, the soot stream comprising soot and exiting the burner at an outlet; and directing a capture medium to the soot stream, the capture medium contacting the soot in an impact region, the soot having a temperature greater than 50° C. in the impact region.

Abstract: A process for manufacturing glass articles from powder at low temperatures includes the steps of preparing a slurry of powder suspended in a liquid; depositing the slurry on a substrate; drying the slurry to form a layer on the substrate; depositing slurry on the layer; drying the slurry deposited on the layer on the substrate to form another layer; repeating the steps of depositing a slurry and drying the to form a plurality of sequential layers on the substrate; and consolidating the plurality of sequential layers to form a glass article. The process requires a small manufacturing footprint, and facilitates the manufacture of very large near-net shape glass articles.

Abstract: A method of melting glass and glass-ceramics that includes the steps: conveying a batch of raw materials into a submerged combustion melting apparatus, the melting apparatus having liquid-cooled walls and a floor; directing a flame into the batch of raw materials and the melted batch with sufficient energy to form the raw materials into the melted batch; and heating a delivery orifice assembly in the floor of the submerged melting apparatus to convey the melted batch through the orifice assembly into a containment vessel. The melted batch has a glass or glass-ceramic composition that is substantially reactive to a refractory material comprising one or more of silica, zirconia, alumina, platinum and platinum alloys.

Abstract: An apparatus for downwardly drawing glass ribbon comprises edge directors, wherein an outer portion defining a first pair of surfaces and a second pair of surfaces. In one example, the first and second pair of surfaces of each edge director includes a glass wettability with a static contact angle within a range of from about 30° to about 60°. In another example, the outer portion comprises a platinum alloy including from about 0.05 weight % tin to about 5 weight % tin. Methods for forming glass include the step of providing the edge director with a desired glass wettability and/or a desired platinum alloy.

Abstract: The present disclosure describes silicon carbide articles useful at high temperatures, and the method of making them. The method includes: providing a plurality of silicon carbide parts; providing a mullite gasket; placing the gasket between the ends of the parts to be joined to thereby form an assembly; applying a load in the range of 15-25 pounds per square inch to the parts' ends distal from the gasket to thereby press the gasket; heating the assembly in a muffle furnace under load to a temperature in the range of 1450° C. to 1550° C.; increasing the load on the to range of 30-50 pounds per square inch and holding the assembly at the temperature for a time in the range of 2-5 days to adhere the mullite gasket to the ends of the silicon carbide parts.

Abstract: A method for forming a porous soot body that includes depositing soot on a release coating supported by a bait substrate. Characteristics of the release coating control the strength of attachment of the porous soot body to the bait substrate. Weak attachment of the porous soot body to the bait substrate facilitates separation of the porous soot body from the bait substrate without damaging the porous soot body. The release coating may be formed from a brittle material or a material that oxidizes or otherwise depletes during deposition of the soot that forms the porous soot body. The release coating may include carbon. The separated porous soot body may be consolidated to form a core cane or may function as a sleeve (porous cladding) in a cane-in-soot fiber preform manufacturing process.

Abstract: A cross-linkable composition with controlled cross-linking as a material is used for fixing and thermally insulating tubes used for casing in drill holes, especially oil drill holes, during exploitation operations, such as oil extraction, in the drill hole. The cross-linkable composition includes at least one diene polyol, at least one polyisocyanate, and at least one heat insulating liquid filler.

Abstract: The present disclosure describes a silicon carbide articles useful at high temperatures, and the method of making them. The method comprises providing a plurality of silicon carbide parts; providing a mullite gasket; placing the gasket between the ends of the parts to be joined to thereby form an assembly; applying a load in the range of 15-25 pounds per square inch to the parts' ends distal from the gasket to thereby press the gasket; heating the assembly in a muffle furnace under load to a temperature in the range of 1450° C. to 1550° C.; increasing the load on the to range of 30-50 pounds per square inch and holding the assembly at the temperature for a time in the range of 2-5 days to adhere the mullite gasket to the ends of the silicon carbide parts.

Abstract: A method and apparatus for making an optical fiber preform. The apparatus has an outer wall and an inner wall. The outer wall surrounds the inner wall and the inner wall surrounds an inner cavity of the apparatus. A core rod is deposited in the inner cavity after which particulate glass material, such as glass soot, is deposited in the inner cavity around the core rod. The core rod has at least 10 percent of the final cladding soot already applied thereto. A radially inward pressure is applied against the particulate glass material to pressurize the particulate glass material against the core rod.

Abstract: An apparatus for downwardly drawing glass ribbon comprises edge directors, wherein an outer portion defining a first pair of surfaces and a second pair of surfaces. In one example, the first and second pair of surfaces of each edge director includes a glass wettability with a static contact angle within a range of from about 30° to about 60°. In another example, the outer portion comprises a platinum alloy including from about 0.05 weight % tin to about 5 weight % tin. Methods for forming glass include the step of providing the edge director with a desired glass wettability and/or a desired platinum alloy.

Abstract: A method of preparing an optical preform includes the steps of: a) etching an optical preform to remove a portion of an oxide material deposited on the preform by using a gas comprising an etchant gas containing fluorine at a sufficient temperature and gas concentration to create a redeposited germanium containing compounds contamination such as GeOx in the remaining oxide material; and b) cleaning the etched preform using a cleaning gas containing at least one halogen gas at a sufficient temperature and gas concentration to remove the redeposited germanium containing compound contamination without any substantial further contamination of the remaining deposited oxide material. Preferably the halogen is either chlorine or bromine.

Abstract: An apparatus for downwardly drawing glass ribbon comprises edge directors, wherein an outer portion defining a first pair of surfaces and a second pair of surfaces. In one example, the first and second pair of surfaces of each edge director includes a glass wettability with a static contact angle within a range of from about 30° to about 60°. In another example, the outer portion comprises a platinum alloy including from about 0.05 weight % tin to about 5 weight % tin. Methods for forming glass include the step of providing the edge director with a desired glass wettability and/or a desired platinum alloy.