摘要:
A ceramic filter which includes a plurality of end-plugged honeycomb structures which in combination act to trap and combust diesel exhaust particulates. The exhaust gas flows substantially equally through the end-plugged honeycombs. Preferably the ceramic filter includes two end-plugged honeycomb structures composed of a plurality of alternatingly end-plugged cell channels extending from an inlet face to an outlet face. The end-plugged honeycomb structures are arranged either parallel or perpendicular to the flow of the exhaust gas.
摘要:
This invention relates to a method of producing an alumina porous material using a mixed powder of alumina powder and aluminum hydroxide represented by the chemical formula Al(OH)3 at different percentages as the starting material, comprising the steps of heating this mixed powder to decompose the aluminum hydroxide and further heat treating it within a temperature range of 1,000 to 1,600null C., and to the alumina porous material produced by the above-mentioned method with a porosity exceeding 40 volume % and its specific surface area of 8 to 40 m2/g, and further to a filter and catalyst carrier that are obtained using this alumina porous material.
摘要:
A method and cementing composition that includes gas generating additives for compensating for or offsetting hydration volume shrinkage of the cementing compositions. The method comprises placing the cementing composition in a subterranean zone and allowing the cement composition to set into a solid mass therein.
摘要:
A fire resistant wood door is formed from an opposing pair of rails interconnected by a upper and lower stiles forming an outer frame. A wood laminate core is provided within the outer frame and covered by outer sheathing. The wood laminate core is formed from first and second panels and a heat barrier layer. Each of the first and second panels is formed from an organic material and provided with a plurality of grooves on one surface. The heat barrier layer is in the form of a casting applied to the grooved surface of at least one, and preferably both, of the first and second panels. The panels are then joined together with the heat barrier layer sandwiched therebetween. When joined with the outer frame and sheathing, a wood door is formed having a fire rating of at least 45 minutes.
摘要:
Cement compositions comprising flexible, compressible beads, processes for preparing such cement compositions, and methods of cementing in subterranean formations using such cement compositions. One or more flexible, compressible beads are mixed with the cement before pumping the cement into a well bore. The flexible, compressible beads are preferably composed of an elastomeric material such as a copolymer of methylmethacrylate and acrylonitrile; a terpolymer of methylmethacrylate, acrylonitrile, and dichloroethane; a styrene-divinylbenzene copolymer; and polystyrene. The flexible, compressible beads may be heated to expand the beads before mixing with the cement such that the ensuing cement composition will have a desired density. Non-flexible beads such as spherulites may also be added to the cement compositions.
摘要:
Powder of a metal serving as a precursor for ceramics (1) and a sintering additive are mixed with each other and heat-treated by microwave heating thereby nitriding or oxidizing the metallic powder from the surface thereof and diffusing the metal with a nitride or an oxide formed on the shell of the metal for obtaining porous ceramics (1) having homogeneous and fine closed pores (1a). The porous ceramics (1) according to the present invention, having the closed pores (1a) homogeneously diffusing at a high ratio, exhibits excellent characteristics when applied to an electronic circuit board or the like requiring moisture absorption resistance, low permittivity and low dielectric loss as well as mechanical strength.
摘要:
Producing both colored and noncolored lightweight aggregates. The processes involve mixing a lightweight fine material such as ash with cement, and optionally pigment, then agglomerating the mixture, curing, and sizing the lightweight aggregate. Calcium stearate is added to the lightweight aggregate for reducing the moisture permeability of the lightweight aggregate end product. The colored and noncolored lightweight aggregate may be used in a variety of ways such as to provide a lightweight concrete mix with the same exterior and interior color, and for other asphalt pavement, geotechnical, horticulture, and specialty uses.
摘要:
A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed, wherein the composition comprises water, at least about 30% by weight of an acid component, at least about 0.1% by weight of a source of fluoride ions, and a stable foam forming amount of a foaming agent system composed of a non-ionic alkyl polyglycoside alone or with additional non-ionic foaming agents. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition in the form of a foam also disclosed.
摘要:
The present invention provides a silicon nitride filter which is a filter excellent in heat resistance, thermal shock resistance, corrosion resistance, acid resistance and mechanical strength and suitable for dust arresting or dust removing, and which is particularly useful as a filer for particulates, and a method for its production. The present invention provides a method for producing a silicon nitride filter, characterized by heat-treating in nitrogen a green body comprising from 40 to 90% of metal silicon particles having an average particle diameter of from 1 to 200 nullm and from 10 to 60% of a pore-forming agent, provided that the total amount of the metal silicon particles and the pore-forming agent is at least 90%, to form a porous product made substantially of silicon nitride. The present invention provides a silicon nitride filter characterized in that the porosity is from 40 to 70%, and the cumulative pore volume of pores with diameters of at most 1 nullm is from 1 to 15 vol % of the total pore volume.
摘要:
This invention relates to a formulation with the addition of low density additives of volcanic ash, hollow ceramic microspheres or a combination of microspheres and volcanic ash or other low density additives into cementitious cellulose fiber reinforced building materials. This formulation is advantageously lightweight or low density compared as compared to current fiber cement products without the increased moisture expansion and freeze-thaw degradation usually associated with the addition of lightweight inorganic materials to fiber cement mixes. The low density additives also give the material improved thermal dimensional stability.