Abstract: An orbiting blade rotary machine, especially for use in compressor and expansion motor units, includes a stator housing bounding an internal space that includes a substantially cylindrical internal chamber centered on a central axis. A power shaft extends in a centered relationship along the central axis through the internal space, being mounted on the stator housing for rotation about the central axis. Each of a plurality of orbiting blades extends substantially radially outwardly from the power shaft in the internal chamber toward the stator housing in its neutral position, being supported on the power shaft for pivoting within a limited angular range around the neutral position. An eccentric rotor is mounted in the stator housing for rotation about an eccentric axis parallel to and transversely offset from the central axis, being accommodated in the internal chamber to delimit a working space that the orbiting blades subdivide into individual compartments.

Abstract: A carbon-based material substrate of a cathode electrode of an acid electrolyte fuel cell is made corrosion resistant by depositing a material that is nonwettable by the electrolyte on that major surface of the substrate which carries a catalyst layer all over except for its edge regions to cover such major surface at least at one of those of its edge regions which are exposed to an oxidizing gas during the operation of the fuel cell, but advantageously also at an additional one of its edge regions that is remote from the one edge region but is also exposed to an oxidizing gas during the operation of the fuel cell. The corrosion resistance can be further improved by extending the catalyst layer of the anode electrode on all sides beyond the cathode catalyst layer.

Abstract: A support plate for a proton exchange membrane fuel cell includes a porous support body that has a central portion and a peripheral portion integral with and circumferentially completely surrounding the central portion, and a sealing body of elastomeric sealing material that completely fills the pores of the peripheral portion to make it impermeable to fluids. The support plate may be assembled with another one and with a proton exchange membrane interposed between the two support plates to form an assembly, and the sealing body then peripherally joins and seals the assembly and fills any gaps that may be present between the peripheral portions due to the absence of the membrane from such regions and thus to peripherally encapsulate the membrane.

Abstract: An internally cooled proton exchange membrane fuel cell device includes a fuel cell including a pair of substantially coextensive electrode components each of which includes a porous central region and a fluid-impermeable peripheral region circumferentially completely surrounding the central region, and a proton exchange membrane component interposed between at least the central regions of the electrode components. The fuel cell device further includes an arrangement for cooling the fuel cell, including at least one enclosed cooling channel situated at the peripheral region of one of the electrode components and supplied with fresh cooling medium, with the spent cooling medium being discharged from the cooling channel. There is further provided a heat transfer device that is operative to transfer heat from the central region to the peripheral region of the one electrode component.

Abstract: An optical correlation system employing the degenerate four wave mixing uses cross-polarized pump and probe beams to prevent the writing of a volume transmission phase hologram in a photorefractive crystal having an applied electric field parallel to the optic axis of the system, so that system response does not depend on the time required to write or erase such a transmission hologram.

Abstract: Electrodes for an acid fuel cell are disclosed. The electrodes include a porous substrate and a catalyst layer supported on the substrate. The catalyst layer includes catalyst particles, a hydrophobic binder for providing a network of hydrophobic gas passages communicating with the catalyst particles and hydrophilic catalytically inactive particles for providing a network of liquid transport passages throughout the catalyst layer. The electrodes provide improved resistance to flooding and pumping and may be operated at high current density without developing severe concentration polarization.

Abstract: An actuator device of particular use in changing the configuration of a deformable mirror faceplate includes an electrically deformable actuator confined between a back surface of a support and a nut that is threaded onto a threaded end portion of elongated tensioning element that has an end cap secured to the other end portion. The tensioning element passes through a central opening of the actuator and a passage in the support. A spring is interposed between the front surface of the support and the end cap. Tightening of the nut imparts causes the spring to exert its restoring force on the actuator to subject the same to a mechanical preload pressure. Another nut may be threaded onto the threaded end portion of the tensioning element to be received in a corresponding recess of the support and pre-deform the spring in the absence of the actuator.

Abstract: An arrangement for replenishing hydrogen consumed in a fuel cell device includes a reaction vessel that contains a quantity of a material that releases hydrogen on contact with water in a highly exothermic reaction. A hydrogen-containing gaseous medium is passed through the material quantity under conditions resulting in removal of heat from the material quantity by convection at a heat removal rate sufficient to maintain a temperature differential between an inlet portion and an outlet portion of the reaction vessel below a predetermined level. This includes recirculating a portion of the gaseous medium from the outlet portion to the inlet portion and cooling at least the recirculated portion.

Abstract: An optic intensity modulator includes a substrate of an optic material that is conductive to light and acoustic waves and has both electrooptic and piezoelectric properties. A pair of associated elongated light waveguides is formed in the substrate, with the waveguides extending substantially coextensively with one another, and being separated from one another by a transverse distance that gradually varies along the courses of the waveguides. Each of two portions of light of substantially identical properties is launched into one of the waveguides for propagation longitudinally thereof, and different phase shifts are induced in the light portions as they propagate in the waveguides by imposing different variable electric fields onto each of the waveguides. The light portions are combined with one another subsequently to their emergence from the waveguides with attendant amplitude modulation of the combined output light due to interference between such phase-shifted light portions.

Abstract: A fuel cell stack includes a plurality of fuel cells juxtaposed with one another in the stack and each including a pair of porous plate-shaped anode and cathode electrodes that face one another, and a quantity of liquid electrolyte present at least between the electrodes. A separator plate is interposed between each two successive electrodes of adjacent ones of the fuel cells and is unified therewith into an integral separator plate by forcing most of a quantity of an electrolyte-nonwettable material, which is originally introduced into the respective interface as a sheet of such material, into the pores of the respective electrodes. A circumferentially complete barrier that prevents flow of shunt currents onto and on an outer peripheral surface of the separator plate is formed by extruding the remainder of the electrolyte-nonwettable material out of the respective interface.

Abstract: A lider countermeasure receives an interrogating laser beam and returns a beam having a distorted phase point such that the interrogating system generates a false angular portion for the returned radiation. The false phase front is achieved by independent manipulations of the amplitude and phase of the returned signal.

Abstract: A fuel cell stack includes a plurality of fuel cells juxtaposed with one another in the stack and each including a pair of plate-shaped anode and cathode electrodes that face one another, and a quantity of liquid electrolyte present at least between the electrodes. A number of separator plates that are substantially impermeable to liquids but wettable by electrolyte is interposed between respective successive electrodes of adjacent ones of the fuel cells. Each such separator plate has edge portions situated at a periphery of the fuel stack and having a peripheral surface, and marginal surfaces respectively facing the successive electrodes and forming respective interfaces therewith.

Abstract: A composite yet monolithic free abrasive grinding lap includes a sintered porous matrix of ceramic or metal material and a quantity of silicon filler material, substantially completely filling the pores of the sintered porous matrix preform at least throughout an effective region of the lap that is to come in contact with a workpiece to be acted upon by the lap. The lap may further have a multitude of abrasive particles embedded in the filler material at the effective region. The lap is made by first slip-casting a preform, then freezing and freeze-drying the same, followed by lightly sintering the dry preform into a porous matrix preform, bringing the temperature of the preform to above the melting point of the silicon filling material, and filling the pores with the filling material in its molten state.

Abstract: An arrangement for solder-coating respective end portions of elongated components in a molten solder bath includes a fixture to be loaded with the components. This fixture includes at least one supporting wall that is capable of maintaining the fixture afloat in a predetermined position on an upper surface of the molten solder bath even when the fixture is fully loaded. The supporting wall has at least one opening through which one of the end portions of a respective component passes into the molten solder bath to a depth necessary for the molten solder to coat the respective end portion to the desired extent when the fixture floats in its predetermined position on the molten solder bath.

Abstract: A phase-locked ridge waveguide gas laser includes a body that circumferentially bounds an elongated internal space extending along a longitudinal main plane and bisected by a longitudinal central plane. The internal space contains a gaseous lasing medium that is excited at radio frequency with attendant light emission from the gaseous medium. Mirrors are so positioned relative to the body as to provide lasing of the light emission. Respective ridges partition the internal space into a plurality of laser resonator cavities each sustaining a guided mode of the lasing light emission. Each of the cavities extends longitudinally of the body and is spaced from an adjacent cavity by a predetermined distance in a width direction of the internal space.

Abstract: A fuel cell stack includes a plurality of fuel cells juxtaposed with one another in the stack and each including a pair of plate-shaped anode and cathode electrodes that face one another, and a quantity of liquid electrolyte present at least between the electrodes. A separator plate is interposed between each two successive electrodes of adjacent ones of the fuel cells and is unified therewith into an integral separator plate. Each integral separator plate is provided with a circumferentially complete barrier that prevents flow of shunt currents onto and on an outer peripheral surface of the separator plate. This barrier consists of electrolyte-nonwettable barrier members that are accommodated, prior to the formation of the integral separator plate, in corresponding edge recesses situated at the interfaces between the electrodes and the separator plate proper.

Abstract: A narrowband laser source includes an optical fiber section including a core centered on a longitudinal axis and a cladding surounding the core, and having a grating region embedded in the core. The grating region includes a multitude of Bragg grating elements extending with a substantially equal longitudinal spacing substantially normal to the longitudinal axis for the grating region to significantly reduce the amount of light passing therethrough when the frequency of such light is in a predetermined narrow range around and including a predetermined center frequency, to an extent proportionate to the deviation of such frequency from the center frequency. A portion of the light emitted by a laser at a frequency dependent on the amount of electric energy applied to the laser is supplied into the core of the fiber section for propagation toward the grating region.

Abstract: A phase change material cooled mirror arrangement includes a mirror substrate which has a reflective front major surface and a rear major surface. The mirror is cooled by advancing at least one rod of a solid phase change material toward the rear major surface of the mirror substrate for gradual melting of the material at the rear major surface by heat absorbed from the substrate with attendant cooling of the latter, at an advancement speed sufficient for the solid phase change material to make up for the amount of such material that has been transformed into liquid by the melting thereof. The liquid phase change material is then removed from the vicinity of the substrate and possibly resolidified and added to the trailing end of the rod in a recirculating system.

Abstract: The luminosity of electroluminescent display pixels arranged at intersection regions between row and column electrodes is controlled so as to compensate for the effect of interelectrode coupling by reducing the voltage differentials applied between the row electrode being addressed and the column electrodes relative to those coresponding to initial pixel luminosity data contained in an incoming data stream, as a direct function of total row luminosity information extracted from that segment of the incoming data stream which pertains to the respective row.

Abstract: A jet engine designed to power a supersonic airplane throughout a range of speeds from subsonic to high supersonic includes a housing which bounds an internal passage having in succession a fixed-area inlet section, a diverging passage section, a mixing section, a combustion section, and an outlet section. A fan rotor rotates in the inlet section and includes a plurality of rotor blade members. The housing includes a main body and at least one flap which is movable between one end position in which it externally bounds a portion of the diverging passage section and another end position in which it externally delimits a diverging discharge passage connecting the diverging passage section with the exterior of the housing. The cross-sectional area of the outlet section is adjustable.