Abstract: A system is described for use with acoustically levitated objects, which enables close control of rotation of the object. One system includes transducers (18, 20, 22) that propagate acoustic waves along the three dimensions (X, Y, Z) of a chamber (16) of rectangular cross section. Each transducer generates a first wave which is resonant to a corresponding chamber dimension to acoustically levitate an object, and additional higher frequency resonant wavelengths for controlling rotation of the object. The three chamber dimensions and the corresponding three levitation modes (resonant wavelengths) are all different, to avoid degeneracy, or interference, of waves with one another, that could have an effect on object rotation. Only the higher frequencies, with pairs of them (e.g. 50, 52) having the same wavelength, are utilized to control rotation, so that rotation is controlled independently of levitation and about any arbitrarily chosen axis.

Abstract: A method of desulfurization is described in which high sulfur coals are desulfurized by low temperature chlorinolysis (12) of coal in liquid media, preferably water, followed by hydrodesulfurization (26) at a temperature above 500.degree. C. The coals are desulfurized to an extent of up to 90% by weight and simultaneously dechlorinated to a chlorine content below 0.1% by weight. The product coals have lower volatiles loss, lower oxygen and nitrogen content and higher fixed carbon than raw coals treated with hydrogen under the same conditions.Heating the chlorinated coal to a temperature above 500.degree. C. in inert gas such as nitrogen results in significantly less desulfurization.

Abstract: An apparatus and method are described for measuring physical characteristics of a fluid, by placing a drop (16) of the fluid in a bath (14) of a second fluid and passing acoustic waves through the bath. The applied frequency of the acoustic waves is varied, to determine the precise value of a frequency at which the drop undergoes resonant oscillations. The resonant frequency indicates the interfacial tension of the drop (16) in the bath (14), and the interfacial tension can indicate physical properties of the fluid in the drop.

Abstract: Contact electrodes on a semiconductor device (50) such as a photovoltaic solar cell is formed by screening through a mask (38) onto a surface (40) a pattern of ink containing a dispersion of lower melting, sinterable metal (tin) coated base metal (copper) particles dispersed in a liquid vehicle including a vaporizable binder polymer and a fluorocarbon polymer. On firing the screen coated device (46) in an oven (48) the binder polymer is vaporized, the fluorocarbon vapors etch the surface and the coated metal particles sinter without being oxidized to form an adherent, coherent, contact electrode (53).

Abstract: A two-gyro four-gimbal attitude sensing system having gimbal lock avoidance is provided with continuous azimuth information, rather than roll information, relative to the magnetic cardinal headings while in near vertical attitudes, thereby to allow recovery from vertical on a desired heading. The system is comprised of means (48) for stabilizing an outer roll gimbal (14) that is common to a vertical gyro (12) and a directional gyro (10) with respect to the aircraft platform (50) which is being angularly displaced about an axis substantially parallel to the outer roll gyro axis, and means (38) for producing a signal indicative of the magnitude of such displacement (62, 64) as an indication of aircraft heading. Means are provided to cause stabilization of the outer roll gimbal (14) whenever the pitch angle of the aircraft passes through a threshold prior to entering vertical flight and destabilization of the outer roll gimbal (14) upon passing through the threshold when departing vertical flight.

Abstract: The yield of organic extract from the supercritical extraction of coal with larger diameter organic solvents such as toluene is increased by use of a minor amount of from 0.1 to 10% by weight of a second solvent such as methanol having a molecular diameter significantly smaller than the average pore diameter of the coal.

Abstract: A system is provided for analyzing the particles in aerosols, as in making air pollution studies, which enables the making of rapid chemical analyses of particles. The system includes an apparatus for producing a controlled stream of individual particles to be analyzed from an environment, and an apparatus for vaporizing and ionizing the particles while they move in free flight, for analysis by a mass spectrometer. The apparatus for producing a stream of particles includes a capillary tube through which the air with suspended particles moves, a skimmer device having a small opening spaced from an end of the capillary tube to receive particles passing through the tube, and a vacuum pump for pumping air out of the space between the tube and skimmer. The vacuum pump serves to remove much of the gas from around the particles, while also creating an inflow of air and particles through the capillary tube.

Abstract: An electronic control system for a high power load is provided with a plurality of parallel current paths divided into two groups (11-12), with control devices (Q.sub.1 -Q.sub.n) in the current paths of one group each having a current limiting resistor (13), and control devices (Q.sub.21, Q.sub.22) in the current paths of the other group each having no current limiting resistor, so that when the control devices of the second group are turned fully on, a short circuit is achieved by the arrangement of parallel current paths. Separate but coordinated control signals (1, 2) are provided by suitable means (P.sub.1 -P.sub.3) to first turn on the control devices of the first group and increase their conduction toward saturation as a function of control input, and when fully on, or shortly before, to turn on the control devices of the second group and increase their conduction toward saturation as a function of the control input as that input continues to increase.

Abstract: An apparatus is described for moving a probe (12) that engages moving living tissue such as a heart or an artery that is penetrated by the probe, which moves the probe in synchronism with the tissue to maintain the probe at a constant location with respect to the tissue. The apparatus includes a servo positioner (18) which moves a servo member (20) to maintain a constant distance from a sensed object (30) while applying very little force to the sensed object, and a follower (26) having a stirrup (28) at one end resting on a surface of the living tissue and another end carrying a sensed object (30) adjacent to the servo member. A probe holder (34) has one end mounted on the servo member (20) and another end which holds the probe (12). The probe is held adjacent to the stirrup (28) of the follower assembly, so that movements of the tissue and therefore of the follower assembly (26) result in corresponding movement of the probe (12) to follow the surface of the tissue.

Abstract: A manually-operable lock for releasably securing a canopy 10 in closed condition characterized by a pair of dogs 28 mounted in fore-and-aft alignment on the wall of the cockpit of an aircraft, a pair of dog receivers 16 mounted on the canopy in juxtaposition with the dogs when the canopy is in its closed condition, a dog-actuating arm 32 including internal and external arm components 34 and 36, respectively, supported for oscillation about a common axis and pivotally connected to the dogs through a pitman rod 30 for pivotally displacing the dog, a spring-loaded pin 50 mounted on the arm and adapted to be ramp-cammed and positioned in coaxial alignment with a receiving bore 52, when the arm is at the limit of its forward throw, and pin-release means including external and internal components 66 and 60, respectively, for releasing the arm for pivotal displacement.

Abstract: A method is described for forming sharp tips on thin wires, in particular phosphor bronze wires of diameters such as one-thousandth inch used to contact micron size Schottky barrier diodes, which enables close control of tip shape and which avoids the use of highly toxic solutions. The method includes dipping and end (12) of a phosphor bronze wire (14) into a dilute solution (16) of sulfamic acid and applying a current through the wire to electrochemically etch it. The humidity in the room is controlled to a level of less than 50%, and the voltage applied between the wire (14) and another electrode (18) in the solution is a half wave rectified voltage. The current through the wire is monitored, and the process is stopped when the current falls to a predetermined low level.

Abstract: A synthetic aperture radar correlation system including a moving diffuser located at the image plane of a radar processor. The output of the moving diffuser is supplied to a lens whose impulse response is at least as wide as that of the overall processing system. A significant reduction in clutter results.

Abstract: Stimulation the in vitro propagation of Guayule from a nutrient medium containing Guayule tissue by adding a substituted trialkyl amine bioinducing agent to the nutrient medium. Selective or differentiated propagation of shoots or callus is obtained by varing the amounts of substituted trialkyl amine present in the nutrient medium. The luxuriant growth provided may be processed for its poly isoprene content or may be transferred to a rooting medium for production of whole plants as identical clones of the original tissue. Provides method for producing large numbers of Guayule plants having identical desirable properties such as high polyisoprene levels.

Abstract: An improved coating of gasification catalyst for carbon-graphite fibers is provided comprising a mixture of a polyvalent metal such as calcium and a monovalent metal such as lithium. The addition of lithium provides a lighter coating and a more flexible coating when applied to a coating of a carboxyl containing resin such as polyacrylic acid since it reduces the cross-link density. Furthermore, the presence of lithium provides a glass-like substance during combustion which holds the fiber together resulting in slow, even combustion with much reduced evolution of conductive fragments. The coated fibers are utilized as fiber reinforcement for composites.

Abstract: A single-frequency multibeam synthetic aperture radar for large swath imaging is disclosed. Each beam illuminates a separate "footprint" (i.e., range and azimuth interval). The distinct azimuth intervals for the separate beams produce a distinct Doppler frequency spectrum for each beam. After range correlation of raw data, an optical processor develops image data for the different beams by spatially separating the beams to place each beam of different Doppler frequency spectrum in a different location in the frequency plane as well as the imaging plane of the optical processor. Selection of a beam for imaging may be made in the frequency plane by adjusting the position of an aperture, or in the image plane by adjusting the position of a slit. The raw data may also be processed in digital form in an analogous manner.

Abstract: A thin, uniform, firmly adherent coating of metal gasification catalyst is applied to a carbon-graphite fiber by first coating the fiber with a film-forming polymer containing functional moieties capable of reaction with the catalytic metal ions. Multivalent metal cations such as calcium cross-link the polymer such as a polyacrylic acid to insolubilize the film by forming catalytic metal macro-salt links between adjacent polymer chains. The coated fibers are used as reinforcement for resin composites and will gasify upon combustion without evolving conductive airborne fragments.

Abstract: A method and apparatus for convection control of metallic halide vapor density in a metallic halide laser (10). More particularly, an apparatus is disclosed wherein a reservoir (48) containing copper chloride (62), which in the exemplary embodiment is the metallic halide chosen, is heated so that the copper chloride is maintained in a liquid form. The apparatus includes a means for flowing a buffer gas, which in the exemplary embodiment is neon, over the liquid copper chloride to provide a mixture of copper chloride vapor and neon (72') above the liquid copper chloride. A conduit (50) for providing fluid communication between the reservoir (68) containing the copper chloride vapor/neon mixture and the laser (10) is also included. The copper chloride vapor density in the laser is related to the liquid copper chloride temperature and the neon flow rate through the reservoir (68).

Abstract: A method and apparatus are provided for indicating the altitude of the tropopause or of an inversion layer wherein clear air turbulence (CAT) may occur, and the likely severity of any such CAT, which includes directing a passive microwave radiometer on the aircraft at different angles with respect to the horizon. The microwave radiation measured at a frequency of about 55 GHz represents the temperature of the air at an "average" range of about 3 kilometers, so that the sine of the angle of the radiometer times 3 kilometers equals the approximate altitude of the air whose temperature is measured. A plot of altitude (with respect to the aircraft) versus temperature of the air at that altitude, can indicate when an inversion layer is present and can indicate the altitude of the tropopause or of such an inversion layer. The plot can also indicate the severity of any CAT in an inversion layer.

Abstract: A system is described for forming hollow spheres containing pressured gas, which includes a cylinder device (14) containing a molten solid material (20) and having a first nozzle (18) at its end, and a second gas nozzle (24) lying slightly upstream from the tip of the first nozzle and connected to a source (26) that applies pressured filler gas that is to fill the hollow spheres. High pressure is applied to the molten metal, as by moving a piston (22) within the cylinder device, to force the molten material out of the first nozzle and the same time pressured gas fills the center of the extruded hollow liquid pipe that breaks into hollow spheres (12a). The environment (54) outside the nozzles contains gas at a high pressure such as 100 atmospheres, the gas is supplied to the gas nozzle (24) at a slightly higher pressure such as 101 atmospheres, and the pressure applied to the molten material (20) is at a still higher pressure such as 110 atmospheres.

Abstract: A thermal reactor apparatus and method of pyrolyticaly decomposing silane gas into liquid silicon product and hydrogen by-product gas is disclosed. The thermal reactor (1) has a reaction chamber (21) which is heated well above the decomposition temperature of silane. An injecter probe (100) introduces the silane gas tangentially into the reaction chamber (21) to form a first, outer, forwardly moving vortex (22) containing the liquid silicon product and a second, inner, rearwardly moving vortex (23) containing the by-product hydrogen gas. The liquid silicon in the first outer vortex (22) deposits onto the interior walls (28) of the reaction chamber (21) to form an equilibrium skull layer (26) which flows to the forward or bottom end of the reaction chamber where it is removed. The by-product hydrogen gas in the second inner vortex (23) is removed from the top or rear of the reaction chamber by a vortex finder (30).