Abstract:
A method for melting inorganic materials, preferably glasses and glass-ceramics, in a melting unit with cooled walls is provided. The method includes selecting the temperature of at least one region of the melt is selected in such a way as to be in a range from Teff−20% to Teff+20%, where the temperature Teff is given by the temperature at which the energy consumption per unit weight of the material to be melted is at a minimum, with the throughput having been selected in such a way as to be suitably adapted to the required residence time.
Abstract:
Microorganisms or animal cells are cultured in a fluidized or fixed bed bioreactor on porous inorganic sintered support spheres containing inwardly continuous and outwardly open pores. The spheres have a density and diameter such that shear forces created under fluidized bed conditions shear off microorganisms or animal cells grown out of the pores and on the surface of the spheres. Culturing may be carried out in a fixed bed continuous reactor and the bed subjected to intermittent fluidized bed conditions to shear microorganisms or animal cells off the sphere surfaces. The spheres may be coated with a thin plastic layer to increase resistance to abrasion. Also, the spheres may be provided with a surface layer of inorganic and/or organic material for improving immobilization of microorganisms or animal cells. The spheres can be used in degradation of municipal sewage and industrial wastes and for bioengineering production of nutritionally essential and pharmacological substances and other fermentation products.
Abstract:
Fireproof glass, or glass ceramic in a form suitable for use as windowpanes, which will withstand heating in accordance with DIN (German Industrial Norm) 4102 (1970 edition), standard temperature curve I, and having a compressive prestress in the peripheral portion thereof. The glass, or glass ceramic is such that the product of the thermal expansion coefficient, .alpha., and the modulus of elasticity, E, is 1 to 5 kp .times. cm.sup..sup.-2 .times. .degree.C.sup..sup.-1.
Abstract:
A device for the refining of a glass melt at high temperatures according to the skull pot principle is provided. The device includes a skull crucible having walls that are constructed from a plurality of pipes, a high-frequency coil for coupling electrical energy into the contents of the skull crucible, and an inlet and an outlet of the skull crucible being arranged in a melt surface region of the glass melt, wherein the inlet and the outlet are essentially arranged lying opposite one another.
Abstract:
A device and method for the plaining of glasses or glass-ceramics. The device is provided with a melting vat, at least two plaining containers serially connected after the outlet of the melting vat, and at least one of the plaining containers is built in accordance with the skull principle from a plurality of metal tubes comprising a cooling agent connection and a high-frequency device for inductively coupling high-frequency energy into the contents of the plaining container.
Abstract:
An article of manufacture comprising a glass substrate having a thermal expansion of less than 5.0.multidot.10.sup.-6 /K and, coated thereon, a lead- and cadmium-free glaze comprising, in percent by weight, the following components:______________________________________ Li.sub.2 O 0-12 MgO 0-10 CaO 3-18 B.sub.2 O.sub.3 5-25 Al.sub.2 O.sub.3 3-18 Na.sub.2 O 3-18 K.sub.2 O 3-18 BaO 0-12 SiO.sub.2 25-55 TiO.sub.2 0-5 ZrO.sub.2 0-
Abstract:
In a process for manufacturing fiber reinforced composites made or inorganic sinterable material and inorganic fibers the fibers are continuously passed through a bath which works acccording to the fluidized bed principle and which contains a solution of at least one metal alkoxide of the elements of the first to the fourth main groups of the periodic table and the forth and fifth subgroups of the periodic table, which solution already comprises products of hydrolysis and their condensation products, and the fibers moistened with the solution are wound one upon the other to form layers, the moistened and wound fibers are dried, the metal alkoxides on the fibers are completely hydrolyzed and the products of hydrolysis are polycondensated, and the layers of the fibers being adhered by the powder and the polycondensation products of the products of hydrolysis of the metal alkoxides are hot pressed.
Abstract:
The invention relates to a glass which is transparent to UV radiation and which, for a thickness of 1 mm and the wavelength of 253.7 nm has a transmission of at least 75%, a linear coefficient of thermal expansion of 3.8.times.10.sup.-6 to 4.5.times.10.sup.-6 K.sup.-1 in the temperature range from 20.degree. to 300.degree. C. and a hydrolytic resistance of
Abstract:
A process for manufacturing open porous sintered bodies with large open pore volume and defined pore diameters and which at least predominantly consist of glass-ceramics. They are obtained by sintering a mixture of sinterable powder and an inorganic soluble salt with defined grade of grain, the melting point of which is above the densification temperature of the sinterable powder. For the formation of a molded body the mixture of sinterable powder and inorganic salt is submitted to a molding process. The molded body is sintered in a sintering process and the soluble salt being contained in the molded body is lixiviated. As a main constituent the sinterable powder contains a pulverized crystallizable glass powder. The sintering process is performed in such a way that the crystal phases being produced during the crystallization of the crystallizable glass, and therefore the material properties, too, are controlled by the guidance of the sintering process as well as by the ion exchange taking place between the sinterable powder and the inorganic salt and which is controlled by their composition. Afterwards, the sintered body is transformed to the final glass-ceramic texture.
Abstract:
A window composed of a frame having at least two, parallel disposed, spaced glass panes. At least one of the panes is composed of fire-resistant glass. The fire resistant pane can be a borosilicate or alumino silicate glass having a compressive prestress in the peripheral edge portion thereof, and for which the product of thermal expansion .alpha. and the elastic modulus E is 1-5 kp .times. cm.sup.-2 .times. .degree. C.sup.-1.