Abstract:
A UV sensor having a photodetector for measurement of UV radiation, an SiO.sub.2 -containing dispersive element disposed ahead of the photodetector in the direction of incident UV radiation and an optional housing having an entry opening for UV radiation. The dispersive element contains quartz glass with interiorly disposed boundary surfaces, the orientations of which are statistically homogeneously distributed.
Abstract:
This invention relates to the production of high purity fused silica glass through oxidation and/or flame hydrolysis of a halide-free, organosilicon-R compound in vapor form having the following properties:(a) producing a gas stream of a halide-free silicon-containing compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to SiO.sub.2 ;(b) passing said gas stream into the flame of a combustion burner to form amorphous particles of fused SiO.sub.2 ;(c) depositing said amorphous particles onto a support; and(d) either essentially simultaneously with said deposition or subsequently thereto consolidating said deposit of amorphous particles into a virtually nonporous body; the improvement comprising utilizing a halide-free, organosilicon-R compound in vapor form having the following properties:(1) a Si--R bond dissociation energy that is no higher than the dissociation energy of the Si--O bond;(2) a boiling point no higher than 350.degree. C.; and(3) which, upon pyrolysis and/or hydrolysis, will produce decomposition products beside SiO.sub.2 which are deemed to be environmentally safe or the emissions are below acceptable governmental standards.
Abstract:
Method of preparing granular quartz glass which comprises heating a porous granulated silica gel having an alkoxy group content equal to or less than 1 weight percent and a total impurity content of less than 1 part per million, the porous granulated silica gel obtained by hydrolysis of an orthosilicic acid ester of an aliphatic alcohol at a temperature up to 1400.degree. C.
Abstract:
A method for manufacturing a quartz glass substrate with a coating formed includes: surface roughening for a base surface of the quartz glass substrate, on which the sprayed coating is formed; and a heating treatment of heating the substrate after the surface roughening. The base surface is 0.9 μm or more and 5.0 μm or less in arithmetic mean roughness (Ra) in the surface roughening. The heating treatment is performed at a temperature that is equal to or higher than a strain point (temperature at which the viscosity reaches 1013.5 Pa·sec) of the quartz glass.
Abstract:
A transparent β-quartz glass ceramic is provided. The glass ceramic includes a primary crystal phase including a β-quartz solid solution, a secondary crystal phase including tetragonal ZrO2, and a lithium aluminosilicate amorphous phase. The glass ceramic may be ion exchanged utilizing molten nitrate salt baths. Methods for producing the glass ceramic are also provided.
Abstract:
Systems and methods for forming a permanent plug in a subterranean formation include providing a solution of colloidal silica and pumping the colloidal silica into a bore of a subterranean well so that the colloidal silica penetrates pores of the subterranean formation. The colloidal silica within the pores of the subterranean formation is dehydrated to form a glass-like material within the pores of the subterranean formation.
Abstract:
Alkali-free glasses are disclosed having (in weight %) 50≦SiO2≦80%, 2≦Al2O3≦17%, 8≦B2O3≦36%, and greater than or equal to 2% and less than or equal to 25% of at least one of CaO, MgO, BaO, SrO or ZnO. The alkali-free glasses can have a surface layer with greater than 0.2 weight % N. Such alkali-free glasses are achieved by nitriding processes and exhibit increased strength, scratch resistance and chemical durability.
Abstract:
To provide opaque quartz glass having no water absorbing properties and being excellent in infrared light shielding properties, and a method for its production. In the production of opaque quartz glass of the present invention, a fine amorphous silica powder and a pore forming agent are mixed, then molded and heated at a predetermined temperature, to obtain opaque quartz glass wherein contained pores are closed pores, the average pore size of pores is from 5 to 20 μm, and the content density of pores is high, whereby the heat shielding properties are high.
Abstract:
A method for producing synthetic quartz glass by fusion of SiO2 granulate involves synthesizing amorphous SiO2 primary particles, granulating the amorphous SiO2 primary particles to form an open-pore SiO2 granulate, sintering the open-pore SiO2 granulate by heating in a sintering atmosphere at a sintering temperature and for a sintering period to form a densified SiO2 granulate, and melting the densified SiO2 granulate at a melting temperature to form the synthetic quartz glass. To provide an inexpensive production of low-bubble transparent components of quartz glass despite the use of still open-pore SiO2 granulate, the sintering atmosphere, sintering temperature and sintering duration are adjusted such that the densified SiO2 granulate still comprises open pores but manifests a material-specific infrared transmission T1700 at a wavelength of 1700 nm. This transmission is in the range of 50-95% of the infrared transmission T1700 of quartz glass granules of the same material.