Abstract: A system for the examination of a test object for internal flaws (or acoustic discontinuities such as solid-to-gas or solid-to-liquid interfaces) by means of ultrasonic waves. The ultrasonic waves 18 are induced in the object 16 by projecting at least one intense, pulsed laser beam 13 on the object 16 and scanning the beam 18 along the object 16. Another laser beam 23 is projected on the object 16, either opposite the first beam 14 or on the same side adjacent to the first beam 14, so that is reacts with and is frequency-modulated by the ultrasonic wave. The reflected, frequency-modulated beam 24 is fed to an optical heterodyning means 26 which passes through only an optical beam 28 modulated with the ultrasonic frequency to a photodetector 30.

Abstract: Metal matrix composite materials are formed from a reinforcing, submicron-particle material, such as SiC, which is not easily wettable by a matrix metal, such as Al, and therefore cannot be uniformly dispersed in the matrix because the particles agglomerate. A coating 12 of material, such as Si, easily wettable by the matrix metal, is placed on the surface of the particles 10 before mixing the reinforcing particles in the matrix metal.

Abstract: A method for healing surface cracks 10, especially in metals, by scanning a high-energy, diffused, pulsed electron-beam past a crack 10 in a slowly moving specimen object 12. The crack 10 moves laterally with respect to the beam so that the beam pattern 14 is a sawtooth pattern comprising a series of overlapping circles 22, each comprising one pulse of diffused energy.

Abstract: Bead ion exchange resin wastes are disposed of by a process which involves spray-drying a bead ion exchange resin waste in order to remove substantially all of the water present in such waste, including the water on the surface of the ion exchange resin beads and the water inside the ion exchange resin beads. The resulting dried ion exchange resin beads can then be solidified in a suitable solid matrix-forming material, such as a polymer, which solidifies to contain the dried ion exchange resin beads in a solid monolith suitable for disposal by burial or other conventional means.

Abstract: A metal-working tool with augmented electrical and thermal conductivity. In a metal-working tool, such as a drill bit 10, having at least one groove 14 behind a cutting edge 34, a coating 12 is placed on the surface of the groove 14. The coating 12 is formed from a material having a higher electrical conductivity than the material from which the bit 10 is formed and, preferably, the coating material also has a higher thermal conductivity. The coating 12 reduces the resistance of the bit 10, thereby reducing the heating of the cutting edge 34. The improved thermal conductivity also reduces the heating of the cutting edge 34.

Abstract: The present invention is an apparatus for combining pulsed or continuous laser beams into a single coherent output beam wherein the laser beams to be combined are directed to intersect at the surface of a sinusoidal phase grating so that each are diffracted into sets of diffracted beams, the first laser beam striking the sinusoidal phase grating from a first angle of incidence and the other laser beam striking it from an angle of incidence which is the negative of the first. The sinusoidal phase grating features a modulation wavelength which causes a preselected order from each resultant set of diffracted beams to propagate in a direction normal to the sinusoidal phase grating and a modulation depth which maximizes the energy distributed into the normally directed, preselected diffraction order. All other orders are suppressed.

Abstract: Protuberances, or posts 14, for field-emission cathodes, the posts 14 having rounded emitting tips 12. Control of the radius R, of the emitting tips 12 controls the factor 10.sup.8 /.beta.V upon which the current density of each post 14 depends. Proper radius selection for a given value of applied voltage, V, keeps the operating point of the cathode 10 on a region of the current density vs 10.sup.8 /.beta.V curve well below the region of impedance collapse, CG.

Abstract: An angular accelerometer utilizing a sensing element 10 comprising a strain member 18 and a crosswise torsion member 24, both substantially comprising flat beams 18 and 25, respectively. The strain member 18 is affixed at each end to the object whose angular acceleration is to be measured, the angular acceleration vector lying along the axis of the strain member 18. The torsion member 24 is formed with an end mass 26,26' at each end. The strain member 18 is formed from a material such as quartz whose elasticity changes in proportion to the torque it experiences. A high-frequency surface acoustic wave is sent along the strain member and the change in its frequency due to the torque in the strain member 18 is measured.

Abstract: A low inductance magnetic wiggler for use in electron beam type lasers generates a high intensity spatially periodic magnetic field. The wiggler is formed as a plurality of closed conductive loops having their centers spaced along a common axis. Adjacent loops are connected by a conductor extending parallel to the axis, the connecting conductors being positioned alternately on diametrically opposite sides of the loops.

Abstract: A waste management system for a DF or HF chemical laser or certain other types of chemical lasers wherein the exhaust gases of the laser are fed into a reaction chamber 12 having a collection sump region 14 at the bottom. A Supply tank 16 is loaded with lithium and is coupled to the chamber 12 by a valved feed line 18. Heating means 44 maintains the lithium in a liquid state. Pressurization means 40 pumps the lithium through the feed line 18 into an injector 32 which delivers the lithium to the chamber 12 where the lithium reacts with the exhaust gases. The reaction forms solid and/or liquid waste products which are collected in the sump region 14. After the laser is shut off, the pressure means 40 coupled to the supply tank 16 is replaced by a vacuum pump 44 which acts through a return line 20 coupling the tank 16 to the sump region 14. The waste products are drawn out of the chamber 12 into the tank 16, the tank lines 18 and 20 are disjoined, and the tank 16 is emptied.

Abstract: A liquid expulsion apparatus 12 having a rolling diaphragm 20 conforming to the non-circular shape of the storage tank shelf 30, thereby increasing liquid storage capacity within the tank. A gas-driven piston 24, also conforming to the non-circular shape, expels the liquid in rapid fashion and provides the force for rolling the attached non-circular diaphragm 20. Stability in diaphragm 20 during actuation of piston 24 is maintained by varying the local thicknesses t of diaphragm 20 in relationship with the local, cross-sectional radii of curvature R.sub.c.

Abstract: A process wherein coal is reacted with a hot gas stream to produce acetylene. The process comprises the sequential steps of reacting a fuel, oxygen and steam under controlled conditions of temperature to produce a hot gas stream principally comprising hydrogen, carbon monoxide and steam along with minor amounts of carbon dioxide, and essentially free of O, OH and O.sub.2. The hot gas stream is accelerated to a high velocity and impinged upon a stream of particulate bituminous or subbituminous coal and thereafter the mixture of hot gas and coal is decelerated to a velocity of from about 150 to 300 feet per second. The amounts of the streams of particulate coal and hot gas are controlled to produce in the reaction zone a pressure in the range of from about 10 to 100 psia and a temperature of from about 1800.degree. to 3000.degree. F.

Abstract: An internally manifolded plate for a plate/fin-type heat exchanger comprises a side port contiguous with and transverse to at least one channel, and wherein the channel is contiguous with an end port. The plate may be of unibody construction and also include integral side and end external manifolds.

Abstract: A method for forming small-diameter, angled ducts and manifolds in a face plate for a rocket-engine injector or the like. A surface of a circular base plate 16 is formed with an annular flange 18 thereon having two inwardly sloping sides 11 and 13. Grooves 20, 22 are machined along the intersections of the sides 11 and 13 with the surface of the base plate 16 for propellant-containing manifolds 36 and 38. Grooves 10 are etched in spaced sets of two down the sloping sides of the flange from the flange top 24 to the manifold grooves 20,22. The grooves 10, 20, 22 are filled with wax 23 and a layer 26 of metal is electrodeposited over the grooved surface of the base plate 16 to cover the top 24 of the flange 18, the deposited layer forming orifice ducts and propellant manifolds from the grooves. This layer 26 is machined down to a depth at which the orifice ducts 34 are exposed so that orifices 12 appear at the surface 30 of the machined layer. The wax 23 is now removed by heat or a solvent.

Abstract: The present invention is a transmissive phase retarder in which reflection of an incident beam of light is substantially reduced and in which the incident light experiences a phase retardation between the s- and p-plane polarization components of the transmitted light. The transmissive phase retarder includes a transmissive substrate, such as glass, and a plurality of superimposed thin film transparent layers on the transmissive substrate. The adjacent layers of the superimposed thin film layers are made of materials of substantially different indices of refraction, n.sub.i. The optical thicknesses, f.sub.i, of the layers are prescribed so that they satisfy the transmission and retardation requirements in order to produce both maximum transmission and a specified phase shift, .PHI..sub.i, in the s- and p-plane polarization components of the transmitted light for a broadband range of wavelengths at a specified angle of incidence, .theta..sub.

Abstract: A salt system having a reduced rate of corrosion comprises a salt selected from the group consisting of KNO.sub.3,NaNO.sub.3 and mixtures thereof, and a minor amount of a corrosion inhibitor selected from the group consisting of Li.sub.2 O, Na.sub.2 O, CuO, Mgo, NiO, CaO, Al.sub.2 O.sub.3, Cr.sub.2 O.sub.3, SiO.sub.2, Mn.sub.3 O.sub.4, Ti.sub.2 O.sub.3, Y.sub.2 O.sub.3, Na.sub.2 CrO.sub.4, Na.sub.2 Cr.sub.2 O.sub.7, K.sub.2 CrO.sub.4, K.sub.2 Cr.sub.2 O.sub.7, and mixtures thereof.

Abstract: A hot metal-working tool 10 using electrical resistance heating. Metal-working tool 10 comprises seat 12, cutting insert 14 and chipbreaker 16. Electrical current source 35 provides current which flows between metal working edge 30 of insert 14 and the shear zone 80 of a workpiece 72 during the machine operation. Cutting insert 14 comprises two structural components, one of which 26, contacts chip 82 thereby providing a second path for current flow between tool 10 and shear zone 80. Shear zone 80 may thus be heated by current not passing through metal-working edge 30. The invention also provides for the flow of coolant fluid through internal passages in tool 10. The coolant fluid removes heat from metal working region 28 and is then discharged to bathe the region proximate metal working edge 30.

Abstract: A method of introducing N-azido alkyls into cyclic nitramines comprises reacting under non-basic conditions in an inert organic solvent a N-halo alkyl cyclic nitramine with the novel azidation agent acetyl azide to form the corresponding N-azido alkyl cyclic nitramine.

Abstract: A two-mirror system for transforming an azimuthally or linearly polarized laser beam into a beam having a number of sections, the average phase and polarization of each section being substantially similar. Both mirrors are segmented into eight pie-shaped sections, each of which contains a coating that gives a .+-.90.degree. phase shift or the appropriate uniform optical path difference.

Abstract: Polyhalogenated biphenyls such as PCB's, contained in transformer or capacitor oils, are removed from the transformer or capacitor oils by means of a combustible adsorbent which selectively adsorbs polyhalogenated biphenyls from transformer oils and the like. The adsorbent containing the adsorbed polyhalogenated biphenyls and the polyhalogenated biphenyls adsorbed thereon are destroyed by combustion in a molten salt.