摘要:
The invention relates to a blank for producing a dental moulded part such as an inlay, onlay, crown or bridge, and to a method for producing the blank. To be able to machine a dental moulded part, in particular one having thin wall thicknesses, from the blank without difficulty, the blank is designed to consist of a glass ceramic having a density of between 30 and 60% of theoretical density, and of glass-ceramic powder particles with a particle size distribution d90≦80 μm, lithium silicate crystals being present in an amount of 10 to 90% by volume.
摘要:
The present disclosure relates to microspheres (i.e., beads) having a high index of refraction. The disclosure also relates to retroreflective articles, and in particular pavement markings, comprising such microspheres.
摘要:
There is provided a glass composition having a devitrification temperature of 1000° C. or below, a glass transformation temperature (Tg) of 535° C. or below and a specific gravity within a range from 3 to 4.The glass composition has a refractive index (nd) within a range from 1.60 to 1.75 and an Abbe number (νd) within a range from 50 to 60.
摘要:
The present invention relates to microspheres (i.e., beads) that comprise titania and bismuth oxide. The glass microspheres further comprise zirconia. The invention also relates to retroreflective articles, and in particular pavement markings, comprising such microspheres.
摘要:
A device is described for the production of glass drops from a glass melt ntained in a melting furnace and containing radioactive waste. The device comprises a horizontally extending pipe adapted at one end to be connected to the melting furnace so as to serve as glass melt overflow. The other end of the pipe is formed with a pocket-like extension, in the base of which the drip nozzles are arranged. The overflow tube, together with pocket-like extension, is surrounded by a heating device and by an insulated housing. The pipe is connected to a bore in the wall of the melting furnace, and the device is simple to manufacture and install.
摘要:
Method and apparatus for producing small hollow spheres of glass, metal or plastic, wherein the sphere material is mixed with or contains as part of the composition a blowing agent which decomposes at high temperature (T.gtoreq.600.degree. C.). As the temperature is quickly raised, the blowing agent decomposes and the resulting gas expands from within, thus forming a hollow sphere of controllable thickness. The thus produced hollow spheres (20 to 10.sup.3 .mu.m) have a variety of application, and are particularly useful in the fabrication of targets for laser implosion such as neutron sources, laser fusion physics studies, and laser initiated fusion power plants.
摘要:
A method is provided for producing small diameter spherical particles in a narrow size distribution from low viscosity melts. Inert gas is constrained to uniformily envelope and move cocurrently with a free stream extruded from the melt. The stream attenuates in diameter and disintegrates into spherical-like droplets under the influence of surface tension. The droplets quickly solidify into small diameter spherical particles having a narrow size distribution.
摘要:
An optical switch includes a microresonator comprising a silicon-rich silicon oxide layer and a plurality of silicon nanoparticles within the silicon-rich silicon oxide layer. The microresonator further includes an optical coupler optically coupled to the microresonator and configured to be optically coupled to a signal source. The microresonator is configured to receive signal light having a signal wavelength, and at least a portion of the microresonator is responsive to the signal light by undergoing a refractive index change at the signal wavelength. The optical switch further includes an optical coupler optically coupled to the microresonator and configured to be optically coupled to a signal source. The optical coupler transmits the signal light from the signal source to the microresonator.
摘要:
A method fabricates an optical switch comprising a microsphere coated with silicon nanocrystals. The method includes providing a silica optical fiber. The method further includes melting at least a portion of the fiber to form at least one silica microsphere. The method further includes coating the microsphere with a silica layer. The method further includes precipitating silicon nanocrystals within the silica layer by annealing the microsphere. The method further includes passivating the nanocrystals by annealing the microsphere in a hydrogen-containing atmosphere.