摘要:
The channel-plugging of porous ceramic honeycombs to provide wall flow filter bodies therefrom is carried out using water-based cements comprising ceramic powders and soluble alkali metal silicates; the cements form durable plugs that are resistant to thermal and chemical damage upon drying and without firing.
摘要:
A process for forming a porous silicon nitride-silicon carbide body, the process comprising (a) forming a plasticizable batch mixture comprising (1) powdered silicon metal; (2) a silicon-containing source selected from the group consisting of silicon carbide, silicon nitride and mixtures thereof; (3) a water soluble crosslinking thermoset resin having a viscosity of about 50-300 centipoise; and, (4) a water soluble thermoplastic temporary binder; (b) shaping the plasticizable batch mixture to form a green body; (c) drying the green body; (d) firing the green body in nitrogen at a temperature of 1400° C. to 1600° C. for a time sufficient to obtain a silicon nitride-silicon carbide structure.
摘要:
An activated carbon catalyst having sulfur dispersed homogeneously thereon, the sulfur being chemically bonded to the activated carbon. A method of making the catalyst involves forming an intimate mixture of a synthetic carbon precursor and a sulfur-containing material, curing the carbon precursor, carbonizing the carbon precursor, activating the carbonized carbon precursor to produce an activated carbon catalyst having sulfur chemically bonded to said activated carbon and uniformly dispersed thereon.
摘要:
A method for making an activated carbon composite which involves providing a crosslinkable resin and a support material which is wettable by the resin. The support material can be cotton, chopped wood, sisal, non-fugitive material, and combinations of these. The support is contacted with the resin; and the resin and support material are dried. The resin and support material are then shaped, the resin is cured, and the resin and any carbonizable material are carbonized. The carbon is then activated to produce the product composite. An activated carbon composite produced by the above described method in which the carbon is in the form of a continuous structure reinforced by and uniformly distributed throughout non-fugitive support material.
摘要:
A system for adsorbing a plurality of contaminants from a workstream composed of a first stage open-ended activated carbon monolith adsorber, a second stage open ended activated carbon monolith adsorber downstream of the first stage. The first stage activated carbon has an average pore size that is larger than the average pore size of the second stage activated carbon. A method for removing more than one contaminant from a workstream which involves passing a workstream containing more than one contaminant through a first open ended activated carbon monolith adsorber having a pore size suitable for adsorbing the major portion of the larger size contaminant and for allowing the smaller size contaminant to pass through the monolith, to cause adsorption of the major portion of the larger size contaminant by the activated carbon, while allowing the smaller size contaminant to pass through the first monolith, and thereafter passing the effluent from the first adsorber through a second open ended activated carbon monolith adsorber having a pore size suitable for adsorbing the smaller size contaminant to cause adsorption of the major portion of the smaller size contaminant by the second monolith activated carbon. The adsorbed contaminants can then be desorbed by passing a regenerating stream(s) through the respective monoliths.
摘要:
Ceramic matrix composite articles of improved high temperature oxidation resistance are provided, the articles comprising reinforcing fibers disposed within a ceramic matrix, the matrix further comprising a minor matrix addition consisting of a dispersion of fluormica crystallites in a proportion effective to improve the oxidation resistance of the article and ranging up to about 20% by weight of the matrix.
摘要:
Ceramic matrix composite articles comprising a ceramic, glass-ceramic or glass matrix and a fiber reinforcement phase disposed within the matrix consisting of amorphous or crystalline inorganic fibers, wherein there is provided, on or in close proximity to the surfaces of the inorganic fibers, a layer of sheet silicate crystals constituting a sheet silicate interface between the inorganic fibers and the ceramic, glass, or glass-ceramic matrix. Optionally, the composition of the matrix may be the same as the sheet silicate interface so that the matrix provides the sheet silicate layer.
摘要:
A method of making a fiber reinforced glass matrix composite wherein a continuous length of fiber is impregnated with glass and at least partially consolidated to form a fiber-glass matrix system encompassing the continuous length of fibers, cutting the fiber-glass system into a plurality of short fiber reinforced composites, heating the short fiber reinforced composites to form a composite batch wherein the glass matrix is in a molten condition, and molding the composite batch to form a reinforced glass composite article with uniform random distribution of short fibers, is disclosed.
摘要:
Whisker-reinforced zirconia-mullite ceramic articles exhibiting excellent high-temperature modulus of rupture strength and good toughness are provided from batches comprising the free oxides ZrO.sub.2, SiO.sub.2 and Al.sub.2 O.sub.3 in combination with SiC whiskers for reinforcement. Due to the fine oxide particle sizes attainable and the fact that the mullite is formed in situ in the consolidation process, dense, whisker-reinforced mullite composite articles exhibiting excellent high-temperature strength and toughness may conveniently be obtained.
摘要翻译:具有优异的高温断裂强度和良好韧性模量的晶须强化氧化锆 - 莫来石陶瓷制品由包含游离氧化物ZrO 2,SiO 2和Al 2 O 3与用于增强的SiC晶须组合的批次提供。 由于可以达到的氧化物微粒尺寸和在固结过程中原位形成莫来石的事实,因此可以方便地获得显示出优异的高温强度和韧性的致密的晶须强化莫来石复合材料。
摘要:
Semiconductor-on-insulator (SOI) structures, including large area SOI structures, are provided which have one or more regions composed of a layer (15) of a substantially single-crystal semiconductor (e.g., doped silicon) attached to a support substrate (20) composed of an oxide glass or an oxide glass-ceramic. The oxide glass or oxide glass-ceramic is preferably transparent and preferably has a strain point of less than 1000° C., a resistivity at 250° C. that is less than or equal to 1016 Ω-cm, and contains positive ions (e.g., alkali or alkaline-earth ions) which can move within the glass or glass-ceramic in response to an electric field at elevated temperatures (e.g., 300-1000° C.). The bond strength between the semiconductor layer (15) and the support substrate (20) is preferably at least 8 joules/meter2. The semiconductor layer (15) can include a hybrid region (16) in which the semiconductor material has reacted with oxygen ions originating from the glass or glass-ceramic. The support substrate (20) preferably includes a depletion region (23) which has a reduced concentration of the mobile positive ions.