Abstract:
A printing material and process for producing dense glass-ceramic articles by additive manufacturing are provided. The printing material includes a glass frit that densities to a degree that closely approximates the theoretical density before appreciable crystallization occurs. Densification without interference from a crystalline phase enables greater degrees of densification. Further heating of the sintered printing material induces crystallization to form glass-ceramic articles having a density approaching the theoretical density. The printing material and process enable production of high density glass-ceramic articles at modest process temperatures.
Abstract:
A glass/quartz composite structure may comprise aggregate including glass grit, nano-glass crystals, and/or amorphous silica that may be produced from crystalline quartz. The aggregate may be in an amount greater than any other single material by weight of the composite structure, which may further include quartz powder and/or alumina as well as a binding resin. The glass/quartz composite structure may be devoid of crystalline silica. The structure may be formed into a 1.2-1.5 cm thick slab for countertops using standard cabinet perimeter support. The slab may be made by mixing the aggregate, the quartz powder and/or alumina, and the binding resin, pouring the mixture in a mold, and compacting the mixture in the mold. Specific natural mineral components, decorative chips, and/or wet mixture pieces may be added to the composite structure to provide aesthetics of specific natural stones.
Abstract:
The invention concerns a preparation process of a hybrid organic-inorganic material including the following successive steps: a) preparation of a neutral organosilicon sol in at least one organic solvent, b) incorporation of a doping agent into the neutral organosiliconsol, and production of a doped sol, c) incorporation into the doped sol, of an accelerating agent in order to activate the subsequent gelation of the sol, d) condensation of the sol in order to obtain a crosslinked gel, e) drying of the gel and production of a stable doped gel. and the material obtainable by such a method.
Abstract:
The present invention relates to increasing the photosensitivity of optical fibers. One aspect of the present invention comprises a method for rapidly diffusing hydrogen or deuterium into an optical fiber from a gas mixture having a low total hydrogen content to generate changes in the refractive index of the optical fiber. The resulting photosensitive fiber may be used to create optical devices including Bragg gratings and Bragg grating-based devices.
Abstract:
This invention relates to the immobilization of toxic, e.g., radioactive materials, internally in a silicate glass or silica gel matrix for extremely long periods of time. Toxic materials, such as radioactive wastes containing radioactive anions, and in some cases cations, which may be in the form of liquids, or solids dissolved or dispersed in liquids or gases, are internally incorporated into a glass matrix, having hydrous organofunctionalsiloxy groups, e.g., hydrous aminoalkylsiloxy or carboxyorganosiloxy, bonded to silicon atoms of said glass and/or hydrous polyvalent metals bonded to silicon atoms of said glass through divalent oxygen linkages or otherwise immobilized therein, by a process which involves the ion exchange of said toxic, radioactive anions with hydroxyl groups attached to said organofunctionalsiloxy groups or with hydroxyl groups attached to the hydrous polyvalent metal. Thereafter, the resulting glass now characterized by a distribution of internally bonded or immobilized, toxic, radioactive anions can be packaged in suitable containers, and disposed of as by burial, and/or they can be sintered to collapse the pores thereof to disposal or for producing useful radiation sources. The porous glass or a porous silica gel having said silicon-bonded organofunctionalsiloxy groups and/or said hydrous polyvalent metal oxy groups, the pores of said glass or silica gel remaining open and uncollapsed, can be used advantageously as a backfill for an underground radioactive waste burial site and as overpack in the waste disposal container. Also included is a novel method for bonding the polyvalent metal to the porous silica glass or gel by substituting the protons of the silicon-bonded hydroxyl groups thereof with an alkali metal or ammonium cation followed by displacement of said cation with the non-radioactive polyvalent metal cation.
Abstract:
PURPOSE: Provided is a dielectric material for a plasma display panel, which has dielectric properties similar to a conventional glass paste dielectric layer and forms a dielectric layer through a simple process by various coating techniques. CONSTITUTION: The dielectric material for a plasma display panel is prepared by a sol-gel method and comprises an organosilicon compound having a net structure crosslinked by an oxygen atom bonded to a silicon atom or a crosslinkable organic monomer. The plasma display panel is obtained by forming a dielectric layer from the dielectric material using a conventional coating method and firing the dielectric layer by heat or ultraviolet rays.