Abstract: A real time ultrasound imaging system provided with a fixed focus and including coherent demodulation of echo signals followed by time delay and coherent summation of the demodulated signals is described. As the range from which echoes are being received increases, coherent demodulation is maintained. Demodulation and time delay accuracies are relatively easy to maintain over a large field of view and a long range. The system has high resolution and high sensitivity.

Abstract: A B-scan ultrasound probe imaging system including an array of annular transducers is described in which dynamic focussing is provided by coherent demodulation of the echo signals generated in the transducers. As the range from which echoes are being received increases, coherent demodulation is maintained. The system provides improved lateral resolution over a greatly extended useful range.

Abstract: The leakage current in metal oxide varistor bodies is found to vary as a function of applied pressure in the 0.5 kbar to 10 kbar range.A pressure sensing device is conditioned by first prestressing a metal oxide varistor to a pressure above the range of measurement and then releasing the prestress pressure. Upon application of subsequent pressures equal or less than the prestress pressure, the leakage current in the device is found to vary as a function of pressure.

Abstract: A monolithic analog to digital converter having leakage current compensating circuitry is disclosed. First and second charge storage capacitors are formed in a single semi-conductor substrate. An analog signal to be converted and a reference signal are simultaneously applied to the first and second capacitors, respectively. Thereafter, a charge transfer circuit supplies the first capacitor with a plurality of discrete charge packets. The polarity of the charge packets is chosen so as to increase or decrease the voltage across the first capacitor in the direction of the voltage across the second capacitor. When the voltage across the two capacitors become equal, a differential comparator generates an output signal indicating the end of a conversion operation.

Abstract: A charge transfer circuit of the type including first and second charge storage locations and a charge transfer transistor for transferring a plurality of discrete packets of charge from the first to the second charge storage location is disclosed. The charge transfer circuit includes circuitry for compensating for changes in a thermally induced leakage current such that the charge transfer transistor transfers a variable amount of charge from the first to the second charge storage location during each successive charge transfer operation such that the total amount of charge, i.e. the leakage charge plus the transferred charge packet, accumulated by the second charge storage location during each charge transfer operation, is a constant regardless of changes in the temperature or illumination of the transistor.

Abstract: A composite laminar membrane including a flexible microporous support layer and at least one ultrathin permeable nonporous polymeric membrane of 500 angstroms or less in thickness is prepared by a continuous process. A liquid substrate having a well in its upper surface is provided and polymer-containing casting solution is continuously supplied to the well to effect continuous solution spreading across the liquid surface. Solvent is removed and a web of the support material is continuously contacted with the resulting ultrathin membrane to continuously remove it upwardly from a region of the liquid surface. In a preferred embodiment, an additional well spaced from the removal region is employed for producing an additional membrane, which is continuously removed from its liquid surface in contiguous contact with the liquid-contact surface of the first membrane.

Abstract: Impure bisphenol-A can be purified by treatment of a phenol adduct of the latter with methylene chloride and then recovering the purified bisphenol-A.

Abstract: A real time ultrasound imaging system which includes coherent demodulation of echo signals followed by time delay and coherent summation of the demodulated signals is described. As the range from which echoes are being received increases, coherent demodulation is maintained. Demodulation and time delay accuracies are relatively easy to maintain over a large field of view and a long range. The system has high resolution and high sensitivity.

Abstract: A polymer blend comprising a polyalkylene terephthalate, an organopolysiloxane-polycarbonate block copolymer, and a halogenated copolycarbonate having improved impact, heat distortion and flame retardant properties. The polymer blends can be molded or formed into films, sheets, fibers, laminates, or other improved molded articles of manufacture, including reinforced articles by conventional techniques.

Abstract: Electrostatic x-ray imaging apparatus of the type having a gas-filled chamber bounded by a photocathode and a charge-receiving sheet anode has a control mesh positioned in the gas-filled gap and maintained at a positive voltage with respect to the cathode to facilitate high avalanche amplification and has a voltage between the mesh member and the anode chosen in the plateau region of the x-ray photocurrent versus voltage curve, to achieve a nearly constant efficiency of charge collection at the anode, independent of accumulation of charge thereat.

Abstract: A method is described for the discharge of solids from a coal gasifier grate at different radial locations.

Abstract: A process of forming phosphorus containing linear, branched and/or cross-linked polymers of polyphenylene oxides is described which comprises contacting phosphoryl halides with (a) polyphenylene oxides having an average hydroxyl group per molecule value greter than zero including 1.0 or less, or (b) quinone-coupled polyphenylene oxides having an average hydroxyl group per molecule value greater than zero including 2.0 or less, including mixtures of (a) and (b).

Abstract: A heat exchange device for the introduction of thermal energy into and removal of thermal energy from liquid-solid phase change material is described in which the phase change material is maintained in a container, which is slowly rotated about a generally horizontal axis at a substantially constant rotational speed. Means are provided for automatically nucleating the phase change material as required for cyclic operation. The invention is of particular utility in the use of incongruently melting hydrates for the storage of thermal energy.

Abstract: A superconductive film of Nb.sub.3 Ge is produced by providing within a vacuum chamber a heated substrate and sources of niobium and germanium, reducing the pressure within the chamber to a residual pressure no greater than about 10.sup.-5 mm Hg, introducing air into the resulting evacuated chamber in controlled amounts and vaporizing the niobium and germanium to deposit a film of Nb.sub.3 Ge on the heated substrate.

Abstract: A real time ultrasound imaging system which includes coherent demodulation of echo signals followed by time delay and coherent summation of the demodulated signals is described. As the range from which echoes are being received increases, coherent demodulation is maintained. Demodulation and time delay accuracies are relatively easy to maintain over a large field of view and a long range. The system has high resolution and high sensitivity.

Abstract: A method for the storage and retrieval of thermal energy is disclosed, which in a two phase, two component system is able to utilize both the sensible heat of water (always one of the components) and the heat of fusion of the second component (a salt which forms a hydrate). The system to be employed must be graphically definable in a phase diagram including a liquidus, the compositional range of the system being selected so as to lie within the compositional range of the liquidus along which the system is to operate during both the heating and cooling cycles.

Abstract: In connection with a charge sensing device having a P-N junction and which develops background charge as well as signal charge in the operation thereof, a circuit is provided for reversely biasing the P-N junction and maintaining substantially constant voltage across the P-N junction to balance the background charge developed while sensing signal charge collected by the P-N junction and developing an output proportional to the collected signal charge.

Abstract: Sodium chloride and/or potassium chloride is added to an aqueous suspension of the oxides of lead, titanium, zirconium and cationic modifier and stirred until the suspension converts to a gel which is then heated, evaporating the water and melting said chloride in which the oxides dissolve and react precipitating modified lead zirconium titanate.

Abstract: Methods are described for making an improved sensing element and an improved sensor assembly for a halogen gas leak detector. The method of making an improved sensing element includes positioning at least one porous ceramic tubular element doped with sodium carbonate in a high temperature, non-reactive container, surrounding and covering the element with sodium beta-alumina particles, and baking the element in a furnace overnight at a temperature in the range from 1400.degree. C. to 1450.degree. C. The method of making an improved sensor assembly includes the above steps after which a helical heater coil is wrapped snugly around the tubular element, and a platinum wire electrode is positioned substantially within and supported by the tubular element. A suitable cement is applied over the entire helical heater coil and the immediate juxtaposed portions of the tubular element. The sensor assembly is then surrounded by and covered with sodium beta-alumina in a high temperature, non-reactive container.

Abstract: A mass of diamond crystals contacting a mass of elemental silicon are confined within a pressure-transmitting medium. The resulting charge assembly is subjected to a pressure of at least 25 kilobars causing application of isostatic pressure to the contacting masses which dimensionally stabilizes them and increases the density of the mass of diamond crystals. The resulting pressure-maintained charge assembly is heated to a temperature sufficient to melt the silicon and at which no significant graphitization of the diamond occurs whereby the silicon is infiltrated through the interstices between the diamond crystals producing, upon cooling, an adherently bonded integral body.