摘要:
A structure includes a substantially non-conductive frame having an exterior surface. The structure defines a plurality of passages that open to the exterior surface. Mesoporous material is disposed in the plurality of passages and is supported therein by the frame. In a method for making a mesoporous nanocrystalline titania hybrid material, a templating agent, an acid, and a titania precursor is mixed into a template liquid. A frame that defines a plurality of passages is placed into the template liquid. A solvent is evaporated from the template liquid, thereby forming a titania gel encapsulating the templating agent. The gel is heated to remove substantially the templating agent from the non-conductive frame and the titania, thereby leaving a mesoporous titania material.
摘要:
A filter for molten metal is an open-pored porous material comprising particles of refractory material embedded in and bonded together by a carbon matrix bonding material. The filter can be made by forming a porous article from refractory particles, e.g. refractory oxide, carbide or graphite, and a carbon-rich binder, e.g. tar, pitch or an organic (preferably aromatic) polymer that degrades to form carbon on pyrolysis, and then firing the porous article to generate the carbon matrix in which the refractory particles are embedded. The porous article is preferably made by coating a reticulated polyurethane foam with binder and refractory particles, and firing at preferably no higher than 800° C.
摘要:
A multi-channel modular device (10) processes between two fluid streams of different compositions. The device (10) includes a porous body (150) having a first plurality of feed-flow pathways (110) disposed in the body (150) for transporting a first stream (180). A pathway wall (114) surrounds each of the first plurality of feed-flow pathways (110) for processing the first stream (180) into a first composition (1852) and a second composition (1802). At least one feed-flow inlet (1101) is disposed in the body (150) for introducing the first stream (180) into the first plurality of feed-flow pathways (110). At least one feed-flow outlet (1102) is disposed in the body (150) for discharging the remaining first stream containing the second composition (1802). At least one second pathway (210) is disposed in the body (150) for transporting a second stream (280) having a second inlet (2101) and a second outlet (2102). A networked plurality of fluid conduits (152) formed in the porous body (150) provides the flow-conduit for the second stream (280) to sweep the first composition (1852) from each of the first plurality of the feed-flow pathways (110) to the second outlet (2102). A vessel (300) ports the inlets (1101 and 2101) and outlets (1102 and 2102) to provide a second stream flow access and for spacing the body within and away from the inner surfaces of the vessel (300) to provide a gap (310) for access. A partition (350) is disposed in the gap between the body and the vessel for diverting the flow within the gap (310).
摘要:
A honeycomb filter includes an array of interconnecting porous walls which define an array of first channels and second channels. The first channels are bordered on their sides by the second channels and have a larger hydraulic diameter than the second channels. The first channels have a square cross-section, with corners of the first channels having a shape such that the thickness of the porous walls adjoining the corners of the first channels is comparable to the thickness of the porous walls adjoining edges of the first and second channels.
摘要:
Porous ceramics are described, which are produced by a) mixing an aqueous solution of a suitable ionotropically orientable polyanion, either with oxides, hydroxides or hydrated oxides, which are present in the form of a sol, of the metals Al, Zr, Ti and Nb, or with finely crystalline oxides, hydroxides or hydrated oxides, which are present in suspension, of these metals, or with finely crystalline tricalcium phosphate or apatite which are present in suspension, b) bringing the mixed sol obtained as in a) or the suspension obtained as in a) into contact with a solution of a salt of a di- or trivalent metal cation in order to produce an ionotropic gel body, c) compacting the gel body by introducing it into electrolyte solutions which further enhance the syneresis of the polyelectrolyte which was originally formed, d) washing the gel body with water and subsequently impregnating it with a readily volatile, water-miscible solvent, e) freeing the anhydrous gel body or gel bodies obtained as in d) from the readily volatile, water-miscible solvent, f) burning out the organic constituents from the dry gel body or the dry gel bodies obtained as in e), g) sintering the product obtained as in f). A capillary frit is also described. Moreover, the invention describes the use of these materials as a catalyst or as a catalyst support, as a ceramic component for composite materials, as a reversible flow filter and as a slab-like sorbent for chromatography columns, as well as the use of a composite material, which is produced from a granular material of the ceramics which are described, as a dental material, particularly as a dental cement.
摘要:
The present invention provides methods for producing hollow ceramic membranes by electrophoretic deposition. The hollow ceramic membranes may have a small cross-sectional area of about 1.0null10null5 mm2 to about 25 mm2. The cross-sectional configuration of the hollow ceramic membranes may be any geometry such as circular, square, rectangular, triangular or polygonal. The hollow ceramic membranes produced by the methods of the present invention may have multiple layers but always the innermost layer, or the first deposited layer is porous and made by electrophoretic deposition. Subsequent layers may be porous or non porous and deposited before or after sintering the first layer. If it is deposited after sintering, it may require additional sintering steps. Additional layers may be deposited by further electrophoretic deposition, sol-gel coating, dip coating, vacuum casting, brushing, spraying or other known techniques.
摘要:
Self-repairing, fiber reinforced matrix materials include a matrix material including inorganic as well as organic matrices. Disposed within the matrix are hollow fibers having a selectively releasable modifying agent contained therein. The hollow fibers may be inorganic or organic and of any desired length, wall thickness or cross-sectional configuration. The modifying agent is selected from materials capable of beneficially modifying the matrix fiber composite after curing. The modifying agents are selectively released into the surrounding matrix in use in response to a predetermined stimulus be it internal or externally applied. The hollow fibers may be closed off or even coated to provide a way to keep the modifying agent in the fibers until the appropriate time for selective release occurs. Self-repair, smart fiber matrix composite materials capable of repairing microcracks, releasing corrosion inhibitors or permeability modifiers are described as preferred embodiments in concrete and polymer based shaped articles.
摘要:
A graphite article useful in producing a membrane electrode assembly comprising a pair of electrodes and an ion exchange membrane positioned between the electrodes is presented. At least one of the electrodes is formed of a sheet of a compressed mass of expanded graphite particles having a plurality of transverse fluid channels passing through the sheet between first and second opposed surfaces of the sheet, one of opposed surfaces abutting the ion exchange membrane when used in a membrane electrode assembly. At least some of the fluid channels are interconnected to enable flow of fluid therebetween.
摘要:
A method for utilizing ultra-thin catalytic monoliths, internal molding and high concentrations of reactive catalytic species to exploit the unique high surface area of Aerogels in order to achieve catalytic selectivity of the desired gas phase heterogeneous reaction.
摘要:
Fluid permeable graphite article in the form of a glassy carbon coated perforated flexible graphite sheet useful as an electrode and electrically conductive backing material in flow-through type electrical capacitors.