Abstract: A standard reference deformation of a composite material containing a flowable phase and compressible inclusions, such as a prepreg, is measured as the deformation whereat the dominant compressive mode of composite deformation changes from that characteristic of compressible inclusion collapse to that characteristic of resin flow, termed the optimal consolidation deformation. Establishment of this point permits measurement and correlation of physically significant composite properties. For example, material properties of such composite materials are measured under a compressive loading by an ultrasonic transducer at the optimal consolidation deformation. At this point, normally determined to be the deformation at which the second derivative of compressive displacement falls to about zero, compressible inclusions such as voids are eliminated but the flowable phase has not yet begun to flow significantly so as to change the fractions of the phases.

Abstract: A process and product for achieving uniform, stabilized working and setting times for phosphate-bonded magnesia cements, wherein a solid phosphate is mixed with an aqueous ammonium phosphate solution and magnesium oxide to form a cement. The solid phosphate may be provided dry or in a slurry, and may be first mixed with the ammonium phosphate solution or the magnesium oxide. Introduction of the solid phosphate into the cement stabilizes the setting time of the cement, which otherwise may vary from a few minutes to several hours, depending upon the characteristics of the ammonium phosphate solution. The ammonium phosphate solution may be supplied as a 10-34-0 composition that is readily available commercially. In one embodiment of the invention, the solid phosphate is provided as an ammonium phosphate mixture of an 18-46-0 composition, having an ammonium phosphate content above the solubility limit of ammonium phosphate in water.

Abstract: Apparatus for performing sensitive magnetic measurements using cryogenically cooled instrumentation, wherein the instrumentation is separated from the bubbles present in a cryogenic cooling fluid. In one embodiment, the magnetic measurement instrumentation is placed in a tail piece joined by heat conducting bolts to a dewar containing a cryogenic fluid, and heat from the instrumentation is conducted to the cryogenic fluid heat sink by metallic strips reaching to the bolts. The cryogenic fluid does not contact the instrumentation directly, resulting in a significantly reduced level of noise in the instrumentation. The tail piece may also be evacuated to avoid pressure and temperature variations that may cause noise and affect the magnetic instrumentation.

Abstract: A robot positioning apparatus for use with robot devices having a movable portion, wherein the movable portion may be spatially oriented to, and controllably spaced from, a reference surface. Initial locating of the reference surface is accomplished by an approximate positioning subsystem using multiple, angularly oriented units which send and receive acoustic orientation positioning signals in search of the reference surface. Once a return signal is received, switching logic indentifies the necessary reorienting of the movable portion to achieve approximately the proper facing relationship of the movable portion to the surface. For precise positioning and ranging after the facing relation is established, a precision positioning subsystem emits an acoustic signal toward the surface, and a response signal is received back from the surface by at least two, and preferably three, receivers mounted upon the movable portion of the robot device.

Abstract: A process for reducing the valence state of ferrous and other ions present in phosphoric acid by heating the acid in the presence of a pressurized reducing gas, preferably hydrogen. The pressurized gas reduces the ions without an addition of metallic iron or other impurity. This process is desirably used with processes for recovering uranium from wet process phosphoric acid, wherein ferric or uranyl ions in the phosphoric acid are reduced in a pressurized reducing gas.

Abstract: A composite photosensitive material of enhanced sensitivity to, and absorption of, incident radiation, wherein an array of particles of an electrically conducting material is embedded in and dispersed through a semiconducting matrix transparent to the wavelengths of interest, the particles having sizes of from about 1 to about 100 nanometers and having volume fractions of at least about 10 percent. The composite material is usable in photosensitive device applications such as detectors, photocells, photodiodes, and vidicons. Sensitivity to infrared radiation is particularly high where the matrix has a dielectric constant of at least about 10. The preferred particle material for enhanced infrared sensitivity is silver or gold, and the preferred matrix is silicon of CuInSe.sub.2.

Abstract: The weight fractions of the phases of a composite material working specimen are determined nondestructively by first performing a sufficient number of nondestructive and destructive calibration measurements on the properties of calibration specimens. The information learned from the calibration specimens is used in combination with nondestructive measurements of the working specimen to determine the fractions of the phases therein, without damaging the working specimen. In one version of this approach, ultrasonic measurements are used to determine fractions of the fiber and matrix in a nonmetallic composite material.

Abstract: Apparatus for making biomagnetic measurements includes a biomagnetometer for measuring magnetic fields produced by the body and an electromagnetic location measurement and recording system for automatically determining the location of the portion of the body from which the magnetic signals are being gathered. The electromagnetic location recording system permits establishing a real time body frame of reference with respect to the biomagnetometer, so that biomagnetic signals can be correlated directly with body location and structure. The electromagnetic location recording system may be operated continuously at radiation wavelengths which do not interfere with the taking of data, or intermittently with the taking of biomagnetic data, to avoid interference with the measured values of the biomagnetic data.

Abstract: This invention concerns a surgical instrument for positioning and insertion for plasty (prosthetic replacement) of the posterior cruciate ligament of the knee.This instrument is characterized by the fact that it consists of, on the one hand, a chisel composed of a handle (2) and a blade (1) in the shape of an italic `S`, the internal terminal part of which (4) is concave, so that the aforesaid blade (1) may be introduced across the femoral notch up to the posterior face of the tibia, and on the other hand, a guide support (9) fixed firmly to the chisel (1, 2) by clamp (8), which comprises at its extremity, arranged in relation to and at a distance from the concave part (4) of the blade (1), two double branch guides (10) in the direction of the aforementioned concave part (4).

Abstract: A method and apparatus for preparing cast composite materials of nonmetallic particles in a metallic matrix, wherein particles are mixed into a molten metallic alloy to wet the molten metal to the particles, and the particles and metal are sheared past each other to promote wetting of the particles by the metal. The mixing occurs while minimizing the introduction of gas into the mixture, and while minimizing the retention of gas at the particle-liquid interface. Mixing is done at a maximum temperature whereat the particles do not substantially chemically degrade in the molten metal during the time required for processing, and casting is done at a temperature sufficiently high that there is no solid metal present in the melt. Mixing is preferably accomplished with a dispersing impeller, or a dispersing impeller used with a sweeping impeller.

Abstract: A noncontact ultrasonic transducer for studying the acoustic properties of a metal workpiece includes a generally planar magnetizing coil positioned above the surface of the workpiece, and a generally planar eddy current coil between the magnetizing coil and the workpiece. When a large current is passed through the magnetizing coil, a large magnetic field is applied to the near-surface regions of the workpiece. The eddy current coil can then be operated as a transmitter by passing an alternating current therethrough to excite ultrasonic waves in the surface of the workpiece, or operated as a passive receiver to sense ultrasonic waves in the surface by measuring the output signal. The geometries of the two coils can be varied widely to be effective for different types of ultrasonic waves. The coils are preferably packaged in a housing which does not interfere with their operation, but protects them from a variety of adverse environmental conditions.

Abstract: An apparatus and process for continuously and progressively forming components from fiber-containing composite material workpieces having a deformable matrix, wherein bending of the composite material is accomplished by pairs of roller elements between which the composite passes as it moves through the apparatus, and wherein the workpiece may be locally heated within the extent of the roller elements. Rotation of each roller is individually and independently controllable to drive the workpiece forward, retard motion of the workpiece, or freewheel. Retarding motion of selected rollers induces tensile stresses in the workpiece, which counteract the compressive stresses induced during bending so as to maintain the alignment of the fibers.

Abstract: A vacuum-tight nonmetallic Dewar component is fabricated from composite material of nonmagnetic fibers in a resin matrix. The component is cylindrical with a closed end, and is laid up from sheets of the composite material and circles cut from the sheets to form the closed end. The layers are mechanically worked and debulked repeatedly during layup between the addition of successive layers, to remove irregularities that can cause vacuum leaks. The joints between the sheets applied to the cylindrical surface and the circular end pieces are mechanically worked to effect a vacuum-tight seal, and the joints are staggered as between succeeding layers for strength and integrity. The laid up and debulked piece is finally cured.

Abstract: A recumbent bicycle is powered by the driving of a crank spindle that rotates on an axis generally coincident with that of the front wheel. The crank spindle is disposed within a spindle housing supported from the front of the bicycle frame, and the spindle housing supports the front wheel through a steerably turnable intermediate hub. Steering of the handlebars causes the front wheel to turn to steer the bicycle, while the crank spindle remains in a fixed orientation to the frame so that the bicycle can be continuously driven with pedals connected to the crank spindle, which in turn is connected to the rear wheel through a sprocket and drive chain assembly.

Abstract: An ultrahigh carbon steel having a composition of carbon in an amount of from about 0.8 weight percent up to the maximum solubility limit of carbon in austenite, aluminum in an amount of from about 0.5 to about 10 weight percent, an effective amount of a stabilizing element acting to stabilize iron carbide against graphitization, and the balance iron. Preferably, the aluminum is present in an amount of from about 0.5 to about 6.4 weight percent and the stabilizing element is chromium. The steel has excellent ductility and is readily hot, warm and cold worked without cracking. It is particularly useful in superplastic forming operations, and may be processed to a suitable microstructure by any technique which reduces its grain size to about 10 microns or less, and preferably to about 1 micron. Such a very fine grain size is readily acheived with the steel, and the aluminum and stabilizing additions act to retain the fine grain size during superplastic processing.

Abstract: A plastics processing machine component, such as a lined composite heating cylinder or a hardfaced feed screw, wherein a layer of a hard, corrosion-resistant alloy is joined to a component substrate in the form of the part to be protected. The alloy has a composition, in weight percent, of from about 12 to about 16 percent molybdenum, from about 10 to about 14 percent chromium, up to about 1.2 percent carbon, up to about 3.5 percent silicon, from about 0.5 to about 3.5 percent boron, balance nickel. Such alloys are resistant to corrosion damage from hydrogen chloride and hydrogen fluoride environments, have sufficient fluidity to permit centrifugal casting in the temperature range of 1800.degree. F. to 2250.degree. F., and can be tailored to have hardnesses from about 45 to over 60 R.sub.c.

Abstract: Silicon carbide particulate reinforced aluminum alloy matrix composites are formed using techniques which include agitation of a melt of aluminum alloy, containing magnesium, and silicon carbide particulates in a manner whereby the silicon carbide particles are maintained, during agitation, within the body of the melt; the agitation, which involves shearing or wiping of the particles in the liquid, is carried out under vacuum; and may involve incorporation into the melt of an additional amount of magnesium such that that amount compensates for the amount of magnesium which segregates to the carbide surfaces, and is sufficient to effect strengthening of the resulting composite. Aluminum alloy matrix composites, containing copper, are produced using similar agitation and mixing procedures, with the copper being incorporated in such a way as to discourage reaction between the copper and SiC particles.

Abstract: A backup computer power system for powering and controlling a computer which is otherwise powered by a main power source, when the main power source fails or is disconnected, wherein an auxiliary power supply provides power to the computer and an instruction set in the computer controllably shuts down the computer after first allowing optional operator intervention prior to initiation of the programmed shutdown. If the operator chooses to intervene, he can permit completion of the current operations or conduct a manual shutdown procedure. If the operator does not intervene within a predetermined period of time, the instruction set terminates the current activity of the computer, saves the software operating environment of the computer, and shuts down the computer. Optionally, the instruction set can then shut off the auxiliary power supply to save its capacity for later use.

Abstract: A process for beneficiating phosphate containing ores, wherein promoter reagents are added to the ore slurry prior to the addition of collectors and depressants for flotation of the carbonate and silica components. The promoters aid in increasing the rejection of the magnesium present during carbonate and silica flotation steps and recovery of phosphates, so that acceptably low magnesium levels for phosphoric acid production can be achieved in a phosphate concentrate in a single rougher stage. Preferred promoters include sodium carbonate and ammonium hydroxide.

Abstract: Wear-resistant materials and articles, wherein an amorphous material having a hardness of greater than about 1600 VHN is utilized to protect wear-susceptible portions of substrates or is itself made into a wear-resistant article. Amorphous materials having hardnesses greater than about 1600 VHN are found to have surprisingly great wear resistance and can be used to prepare wear-resistant articles. Particularly satisfactory results have been obtained with metal-metalloid systems such as W--Ru--B, Re--Mo--B, Mo--Ru--B, and Co--Nb--B materials.