A method for preparing a sol-gel derived SiO.sub.2 having a very fast bioresorption rate where a sol-gel derived SiO.sub.2 is prepared from a sol comprising water, an alkoxide or inorganic silicate and a lower alcohol using a mineral acid or a base as a catalyst and the sol is aged and dried. The method uses a pH from 1.5 to 2.5, a molar ratio of water to the alkoxide or inorganic silicate of 0.5 to 2.5, a molar ratio of alcohol to the alkoxide or inorganic silicate is 0.5; and the sol is either let to gel without induced changes of composition and without forced drying of the sol, or a change of composition is induced; and within a time of 30 minutes, from the induced change forced drying of the sol is carried out or initiated.

It is difficult to obtain a glassy, monolithic molded body of an inorganic oxide with a high melting point and softening point. Although molding by sintering is possible, it is hard to obtain a molded body which is transparent and has high barrier properties. Further, producing molded bodies with the sol-gel process is costly, and it is difficult to produce a molded bodies of large size. In this invention, a molded body principally composed of inorganic oxides is produced with a method that involves a step in which an inorganic-organic hybrid compound, formed by an organic polymer having a hydroxyl group chemically bonding with an inorganic oxide or a derivative thereof, is heated in an atmosphere in which oxygen is present, and the organic polymer component of the inorganic-organic hybrid compound is oxidized and removed.

It is difficult to obtain a glassy, monolithic molded body of an inorganic oxide with a high melting point and softening point. Although molding by sintering is possible, it is hard to obtain a molded body which is transparent and has high barrier properties. Further, producing molded bodies with the sol-gel process is costly, and it is difficult to produce a molded bodies of large size. In this invention, a molded body principally composed of inorganic oxides is produced with a method that involves a step in which an inorganic-organic hybrid compound, formed by an organic polymer having a hydroxyl group chemically bonding with an inorganic oxide or a derivative thereof, is heated in an atmosphere in which oxygen is present, and the organic polymer component of the inorganic-organic hybrid compound is oxidized and removed.

A method for producing sulfide-based glass ceramics including crystallizing a glass solid electrolyte, wherein the glass solid electrolyte includes: sulfide-based glass comprising at least a sulfur element and a lithium element; and a nitrile compound incorporated into the sulfide-based glass.

A method for producing sulfide-based glass ceramics including crystallizing a glass solid electrolyte, wherein the glass solid electrolyte includes: sulfide-based glass comprising at least a sulfur element and a lithium element; and a nitrile compound incorporated into the sulfide-based glass.

A method for forming a functional part in a minute space includes the steps of: filling a minute space with a dispersion functional material in which a thermally-meltable functional powder is dispersed in a liquid dispersion medium; evaporating the liquid dispersion medium present in the minute space; and heating the functional powder and hardening it under pressure.

A method for forming a functional part in a minute space includes the steps of: filling a minute space with a dispersion functional material in which a thermally-meltable functional powder is dispersed in a liquid dispersion medium; evaporating the liquid dispersion medium present in the minute space; and heating the functional powder and hardening it under pressure.

A continuous sol-gel process for producing silicate-containing glasses and glass ceramics is proposed, comprising the following steps: (a) continuously feeding a silicon tetraalkoxide, a silicon alkoxide with at least one non-alcoholic functional group and an alcohol into a first reactor (R1), and at least partially hydrolyzing by the addition of a mineral acid to obtain a first product stream (A); (b) continuously providing a second product stream (B) in a second reactor (R2) by feeding a metal alkoxide component or continuously mixing an alcohol and a metal alkoxide component; (c) continuously mixing product streams (A) and (B) in a third reactor (R3) for producing a presol to obtain a third product stream (C); (d) continuously adding water or a diluted acid to the product stream (C) to obtain a sol (gelation); (e) continuously filling the emerging sol into molds to obtain an aquagel; (f) drying the aquagels to obtain xerogels; (g) sintering the xerogels to obtain silicate-containing glasses and glass ceramics.

A continuous sol-gel process for producing silicate-containing glasses and glass ceramics is proposed, comprising the following steps: (a) continuously feeding a silicon tetraalkoxide, a silicon alkoxide with at least one non-alcoholic functional group and an alcohol into a first reactor (R1), and at least partially hydrolyzing by the addition of a mineral acid to obtain a first product stream (A); (b) continuously providing a second product stream (B) in a second reactor (R2) by feeding a metal alkoxide component or continuously mixing an alcohol and a metal alkoxide component; (c) continuously mixing product streams (A) and (B) in a third reactor (R3) for producing a presol to obtain a third product stream (C); (d) continuously adding water or a diluted acid to the product stream (C) to obtain a sol (gelation); (e) continuously filling the emerging sol into molds to obtain an aquagel; (f) drying the aquagels to obtain xerogels; (g) sintering the xerogels to obtain silicate-containing glasses and glass ceramics.

Annealing treatments for modified titania-silica glasses and the glasses produced by the annealing treatments. The annealing treatments include an isothermal hold that facilitates equalization of non-uniformities in fictive temperature caused by non-uniformities in modifier concentration in the glasses. The annealing treatments may also include heating the glass to a higher temperature following the isothermal hold and holding the glass at that temperature for several hours. Glasses produced by the annealing treatments exhibit high spatial uniformity of CTE, CTE slope, and fictive temperature, including in the presence of a spatially non-uniform concentration of modifier.