Abstract: An omni-directional antenna assembly is provided for wireless communication devices requiring multiple polarization characteristics. A loop antenna assembly for a communications device operating at a predetermined wavelength and having a transceiver circuit including a signal output and a ground plane, the antenna assembly including a conductive loop element and a conductive leg member coupled to the loop element proximate a loop perimeter, the leg member for supporting the loop element at a distance away from the ground plane of the communications device, the leg member also defining a ground point and a feed point for operatively coupling the loop element to the ground plane and the signal output, respectively, of the transceiver circuit.

Abstract: A reaction-bonded &agr;-alumina filter element is provided. The filter element includes a monolith of porous material having multiple passageways extending from one end face to an opposing end face. The monolith is extruded from a mixture containing at least aluminum metal and alumina powders in a proportion such that on sintering the volume change of the monolith is minimized. The filter body can be used as a filter or as a membrane support for crossflow or dead end flow filter elements. A method for making the filter element is also provided.

Abstract: The present invention discloses a combination patch antenna element and bowtie-shaped slot antenna element together disposed upon a first major surface of a dielectric element. The bowtie-slot antenna element is defined upon the dielectric element within a boundary of the patch antenna element. The bowtie-slot antenna element defines a first antenna electrical resonance frequency characteristic, and the patch antenna element defines a second antenna electrical resonance frequency characteristic. The combination patch antenna element and bowtie-shaped slot antenna element are provided in relation to a ground plane element, such as provided by a printed wiring board of a wireless communications device. An additional optional feature of the antenna includes a plurality of conductive pattern enhancement elements disposed on an opposite side of the dielectric element.

Abstract: A printed antenna comprises an elongate first dipole half element provided on one side of a dielectric substrate. The first dipole half element is end-fed via a microstrip transmission line. A second dipole half element is provided on the opposite side of the dielectric substrate. The second dipole includes first and second elongate elements disposed one on each side of the longitudinal axis of the first dipole half element as viewed through the substrate. The first and second elements are a quarter of a wavelength long and are parallel to the first dipole half element. A ground plane on the second side of the substrate is coupled to the first and second elongate elements at a distance from a free end of the first dipole half element corresponding substantially to a quarter wavelength of the frequency of interest.

Abstract: A cross-flow filtration device which receives a feed stock at a feed end face and separates the feed stock into filtrate and retentate. The device has a structure formed from a plurality of substantially parallel monolith segments of porous material, each segment having a plurality of passageways which extend longitudinally from the feed end face to a retentate end face of the structure. The structure contains a filtrate conduit network comprised of both an intersegment filtrate conduit, formed by the arrangement of the segments, and at least one intrasegment filtrate conduit formed within at least one segment. The filtrate conduit network provides low pressure drop flow paths for filtrate flow through the porous material from the passageways to nearby filtrate conduits, and at least some of the passageways are separated from filtrate conduits by intervening passageways, thereby enabling a high ratio of passageway surface area to volume of the device and a high rate of filtrate removal.

Abstract: A catalytic filtration device for separating a particulate-containing feed stock into a filtrate and a particulate-containing filter cake, having a monolith of porous material containing a plurality of passageways extending longitudinally from an inlet end face to an outlet end face, having a plurality of plugs in the ends of the passageways at the inlet end face and at the outlet end face to prevent direct passage of the feed stock through the passageways from the inlet end face to the outlet end face; a microporous membrane selected to separate the feed stock into a filtrate and particulate-containing filter cake, the membrane applied to at least the wall surfaces of the passageways open at the inlet end face and of mean pore size smaller than the mean pore size of the porous material; the device regenerable by withdrawal of the filter cake from the inlet end face of the device; and a catalyst applied to the device for catalyzing a reaction in the filtrate as it passes through the device.

Abstract: A process for forming a porous inorganic membrane on a porous support is provided. The support is coated with refractory particles which sinter at a first temperature. The coating then is impregnated with an inorganic binder which reacts at a second temperature, lower than the first temperature. The impregnated, coated support then is processed at a temperature at least as high as the second temperature, but less than the first temperature.

Abstract: A back-flushable filtration device is provided. The device includes a monolith of porous material having an inlet end and an outlet end. The passageways of the monolith are plugged at the inlet and outlet ends of the monolith, thereby preventing direct passage of feed stock through the passageways from the inlet end to the outlet end. A microporous membrane of mean pore size smaller than the mean pore size of the monolith material covers the surface of the passageways. Methods for making the back-flushable filter as well as methods for using the back-flushable filter also are provided.