Abstract: Glasses containing one or more rare-earth elements and one or more halides are disclosed including a region locally transformed into crystallized glass that comprises precipitated rare-earth element-containing halide crystals. Also disclosed are molded objects containing dispersed particles of glass containing one or more rare-earth elements and one or more halides and having a region within which the particles are transformed into crystallized glass particles. The crystallized region is invisible under usual light but can be detected using upconversion luminescence generated by irradiation with excitation laser light having a specific wavelength. Disclosed further are methods for preparing such locally crystallized glasses and molded objects, as well as methods for efficient detection of the crystallized region in such glasses or molded objects.

Abstract: A photochemical reactor element containing microcapsulated TiO2 photocatalyst particles dispersed in a polysiloxane matrix is disclosed. The polysiloxane matrix has an oxygen gas permeability not less than 1×10−14 mol·m·m−2·s−1·Pa−1. The photochemical reactor element is produced by dispersing the microcapsulated or naked TiO2 photocatalyst particles in a hydrolyzate-polycondensate sol of a trialkoxysilane or a mixture thereof with a tetra- and/or dialkoxysilane and then shaping the dispersion into the element. The naked TiO2 photocatalyst particles in the element are microcapsulated within a porous silica shell layer in situ by irradiating the element with UV radiation.

Abstract: Transparent methyl-modified silica gel is produced by reacting methyltrialkoxysilane or a mixture thereof with a tetraalkoxy-, trialkoxy- or dialkoxysilane other than the methyltrialkoxysilane with a defined quantity of water at a neutral or acidic pH in the presence of a catalytically effective amount of a metal complex soluble in the methyltrialkoxysilane, and aging the resulting hydrolysate sol to form a gel. Self-sustained films of the transparent gel are produced by spreading the hydrolysate sol onto a nonadherent substrate followed by aging or drying. The gel finds use as a host material for doping optically functional molecules.

Abstract: A novel heat-generating composition comprises an electrically conductive powder, and a crystallizable glass frit which is alkaline-earth borate glass essentially containing at least one component of rare-earth metal oxides and Bi.sub.2 O.sub.3. A novel heat-generating composition comprises a molybdenum silicide as an electrically conductive powder, a glass frit, and an additive which is metal oxide powder and/or metal powder. A novel heat-generating composition comprises a combination of a molybdenum silicide and a nickel silicide as electrically conductive powder, a glass frit, and a nickel powder as an additive. The heat-generating composition is sintered in a nitrogen atmosphere or in air, to produce a heater, which has a low electrical-resistance value and a good heat-resistance.

Abstract: Blue, green, red and yellow emitting fluorescent compositions which emit blue, green, red and yellow light of high luminance under low-velocity electron excitation occurring under acceleration potential below 1KV, particularly below 100V can be obtained by mixing a conductive material having a particle diameter distribution wherein central value is within the range of 2.5 to 14.mu. and standard deviation is not more than 0.7, and specific blue, green, red and yellow emitting phosphors in a mixing weight ratio ranging from 1:99 to 1:4, respectively. The conductive material is selected from the group consisting of a conductive metal oxide, mixtures of more than one kind of conductive metal oxide, a conductive metal sulfide, mixtures of more than one kind of conductive metal sulfide and mixtures thereof. These blue, green, red and yellow emitting fluorescent compositions are used as a fluorescent screen of a low-velocity electron excited fluorescent display device.

Abstract: In an air-tight at least partially transparent container, a phosphor, a gas or gas mixture and a pair of discharging electrodes are contained. The discharge gap is in the range of 0.1 to 3.0mm, and the pressure of the gas or gas mixture sealed in the container is such that the product of the pressure and the discharge gap is in the range of 30 to 300 Torr.mm. The gas or gas mixture has discharge radiation spectra within the region of wavelength shorter than 200nm. The phosphor is a manganese activated aluminate phosphor represented by the formula(M.sup.II.sub.1-x, Mn.sub.x ) O.multidot.zAl.sub.2 O.sub.3where M.sup.II is selected from a group consisting of calcium, strontium, barium, magnesium and zinc, and x and z are numbers within the ranges of 10.sup.-3 .ltoreq.x.ltoreq.7.times.10.sup.-1 and 1.ltoreq.z.ltoreq.20, respectively.