Abstract: New crosslinked elastomeric polytriazines have been prepared by a 4-step procedure which consists of: (1) forming a poly(imidoylamidine) by the reaction under reflux conditions of anhydrous ammonia with certain perfluorinated alkyl or alkylether dinitriles; (2) forming a linear polytriazine by cyclizing the imidoylamidine linkages by reaction with certain perfluorinated alkyl or alkylether acid anhydrides or halides; (3) extending the linear polytriazine chain by further refluxing in anhydrous ammonia; and (4) heating to cyclize the new imidoylamidine linkages and thereby crosslink the polymer.

Abstract: A control valve is provided which is adapted to be connected between a pressure source, such as vacuum pump, and a pressure vessel so as to control the pressure in the vessel. The valve comprises a housing having a longitudinal bore therethrough which is connected between the pump and vessel, and a transversely movable valve body which controls the air flow through an air inlet in the housing. The valve body includes cylindrical and conical shaped portions which cooperates with reciprocally shaped portions of the housing to provide flow control. A filter disposed in the air inlet filters out foreign matter in the air. The bottom end of the valve body screws into the valve housing control knob formed integrally with the valve body controls translation of the valve body and hence opening and closing of the valve.

Abstract: New perfluoroalkyl polytriazines containing pendent iododifluoromethyl groups are prepared by the reaction of perfluoroalkyl dinitriles with ammonia to form poly(imidoylamidines), followed by the cyclization of the imidoylamidine groups with, e.g. various mixtures of a perfluoroacyl fluoride with an .omega.-iodoperfluoroacyl fluoride. The polytriazines obtained can be cured by heat which causes crosslinking at the iododifluoromethyl groups by elimination of iodine and formation of carbon-to-carbon bonds.

Abstract: An anti-inflammatory and analgesic composition containing indomethacin and an H.sub.2 histamine receptor antagonist in an amount sufficient to reduce gastric distress caused by the indomethacin. Usable antagonists are metiamide and cimetidine.

Abstract: A subcutaneous electrode structure particularly suitable for a chronic implant and for taking a low noise electrocardiogram of an active animal such as a rat, dog, monkey, cow or the like, comprises a thin inflexible, smooth disc of stainless steel having a diameter as of 5 to 30 mm, which is sutured in place to the tissue of the animal being monitored. The disc electrode includes a radially directed slot extending in from the periphery of the disc for approximately 1/3 of the diameter. Electrical connection is made to the disc by means of a flexible lead wire that extends longitudinally of the slot and is woven through apertures in the disc and held thereto at the terminal end by means of a spot-welded tab. Within the slot, an electrically insulative sleeve, such as silicone rubber, is placed over the wire. The wire with the sleeve mounted thereon is captured in the plane of the disc and within the slot by means of crimping tabs extending laterally of the slot and over the insulative wire.

Abstract: A variable area exit nozzle arrangement for an aircraft engine having a substantially reduced length and weight which comprises a plurality of longitudinally movable radial vanes and a plurality of fixed radial vanes, the movable radial vanes being alternately disposed with respect to the fixed radial vanes, and means for displacing the movable radial vanes along the longitudinal axis of the engine relative to said fixed radial vanes, said radial vanes radially extending across the main exhaust flow of the engine.

Abstract: In a micro-fluid exchange apparatus for exchanging fluid with an organ, such as the trachea or a blood vessel of a small animal, such as a rat or a mouse, a hollow needle, such as a syringe needle, is provided for penetrating the fluid conduit of the animal. The syringe needle is coupled to a plenum chamber having an inlet and outlet port. The plenum chamber is coupled to the syringe needle via the intermediary of a standard quick disconnect coupling fitting. The plenum chamber is carried at the end of a drive rod which is coupled to a micrometer drive head. The micrometer drive head is slidably and pivotably coupled to a pedestal for adjusting the height and angle of inclination of the needle relative to a reference base support. The needle is positioned adjacent to the incised trachea or a blood vessel of a small animal and the micrometer drive head is operated for penetrating the fluid conduit of the animal.

Abstract: Structural wood paneling or other molded wood compositions consisting of finely divided wood chips, flour, or strands are bound together and hot pressed with a modified novolac resin which is the cured product of a prepolymer made from an aralkyl ether or halide with a phenol and a hardening agent such as hexamethylene tetramine. The fire resistance of these articles is further improved by incorporating in the binder certain inorganic fillers, especially a mixture of ammonium oxalate and ammonium phosphate.

Abstract: A turbojet combustor and method for controlling nitric oxide emissions is provided by employing successive combustion zones wherein after combustion of an initial portion of the fuel in a primary combustion zone, the combustion products of the primary zone are combined with the remaining portion of fuel and additional plenum air and burned in a secondary combustion zone under conditions that result in low nitric oxide emissions. Low nitric oxide emissions are achieved by a novel turbojet combustor arrangement which provides flame stability by allowing stable combustion, which usually result in large emissions of nitric oxide in a primary combustion zone, to be accompanied by low nitric oxide emissions resulting from controlled fuel-lean combustion, ignited by the emission products from the primary zone, in a secondary combustion zone at a lower combustion temperature resulting in low emissions of nitric oxide.

Abstract: New chromatographic materials have been developed to serve as the stationary phase of columns used in the separation of atmospheric gases. These materials consist of a crosslinked porous polymer matrix, e.g., a divinylbenzene polymer, into which has been embedded an inorganic complexed ion such as N,N'-ethylene-bis(acetylacetoniminato)-cobalt (II). Organic nitrogenous bases, such as pyridine, may be incorporated into the chelate polymer complexes to increase their chromatographic utility. With such materials, the process of gas chromatography is greatly simplified, especially in terms of time and quantity of material needed for a gas separation.

Abstract: Polymeric membranes suitable for use in reverse osmosis water purification because of their high urea and salt rejection properties are prepared by generating a plasma of an unsaturated hydrocarbon monomer and nitrogen gas from an electrical source and forming a polymeric membrane by depositing a polymer of said unsaturated monomer from said plasma onto a substrate, such that nitrogen from the nitrogen gas is incorporated within the polymer in a chemically combined form.

Abstract: A process for the preparation of composite laminate structures of glass cloth preimpregnated with polybismaleimide resin and adhered to a polybismaleimide-glass or aromatic polyamide paper honeycomb cell structure filled or partially filled with a syntactic foam consisting of a mixture of bismaleimide resin and carbon microballoons.The carbon microballoons are prepared by pyrolyzing phenolic microballoons and subsequently bonded using a 2% bismaleimide solution. The laminate structures are cured for two hours at 477.degree. K. and are adhered to the honeycomb bismaleimide adhesive using a pressure of 700 kN/m.sup.2 pressure at 450.degree. K. The laminate composite is then post-cured for two hours at 527.degree. K. to produce a composite laminate having a density in the range from about 95 kilograms per cubic meter to 130 kilograms per cubic meter.

Abstract: Sweat collection capsule permitting quantitative collection of sweat, comprising a frame held immobile on the skin, a closure secured to the frame and absorbent material located next to the skin in a cavity formed by the frame and the closure. The absorbent material may be removed from the device by removing the closure from the frame while the frame is held immobile on the skin.

Abstract: An induction powered implanted monitor for epidurally measuring intracranial pressure and telemetering the pressure information to a remote readout. The monitor utilizes an L-C oscillator in which the C comprises a variable capacitance transducer, one electrode of which is a small stiff pressure responsive diaphragm. The oscillator is isolated from a transmitting tank circuit by a buffer circuit and all electric components in the implanted unit except an input and an output coil are shielded by a metal housing.

Abstract: The present invention is directed to a support structure formed from a compound strap consisting of two or more links of different thicknesses. More particularly, the compound strap includes a thinner link which is connected to the cool end of the inner storage tank's outer wall and a thicker link which is connected to the warmer outer wall of a relatively larger outer tank which encloses the inner tank to provide a vacuum space. This vacuum space around the inner tank contains the thermal support straps preferably made of fiberglass epoxy resin material used to support the inner tank from the inner wall of the outer tank. The compound strap of the present invention minimizes the heat leak between the inner tank and the outer tank.

Abstract: Flame and temperature resistant polyimide foams are prepared by the reaction of an aromatic dianhydride, e.g., pyromellitic dianhydride, with an aromatic polyisocyanate, e.g., polymethylene polyphenylisocyanate (PAPI) in the presence of an inorganic acid and a lower molecular weight alcohol, e.g., dilute sulfuric acid or phosphoric acid and furfuryl alcohol.The exothermic reaction between the acid and the alcohol provides the heat necessary for the other reactants to polymerize without the application of any external heat. Such mixtures, therefore, are ideally suited for in situ foam formation, especially where the application of heat is not practical or possible.

Abstract: Polyimide foam products having greatly improved burn-through and flame-spread resistance are prepared by the reaction of aromatic polyisocyanates with aromatic dianhydrides in the presence of metallic salts of octoic acid. The salts, for example stannous octoate, ferric octoate and aluminum octoate, favor the formation of imide linkages at the expense of other possible reactions.

Abstract: Impulsive noise reduction is provided in a rotor blade by "acoustically sweeping" the chord line from root to tip so that the acoustic radiation resulting from the summation of potential singularities used to model the flow about the blade tend to cancel for all times at an observation point in the acoustic far field.

Abstract: A segmented controller arm configured and dimensioned to form a miniature kinematic replica of a remotely related slave arm. The arm includes a plurality of joints for affording segments of the arm simultaneous angular displacement about a plurality of pairs of intersecting axes, a plurality of position sensing devices for providing electrical signals indicative of angular displacement imparted to corresponding segments of the controller shaft about the axes, and a control signal circuit for generating control signals to be transmitted to the slave arm. The arm is characterized by a plurality of yokes, each being supported for angular displacement about a pair of orthogonally related axes and counterbalanced against gravitation by a cantilevered mass affixed thereto whereby the controller arm may be released without introducing unwanted motion in the slave arm resulting from gravitation of segments of the master arm.

Abstract: The combination of a "C" mode scan electronics in a portable, battery powered biomedical ultrasonoscope having "A" and "M" mode scan electronics, the latter including a clock generator for generating clock pulses, a cathode ray tube having X, Y and Z axis inputs, a sweep generator connected between the clock generator and the X axis input of the cathode ray tube for generating a cathode ray sweep signal synchronized by the clock pulses, and a receiver adapted to be connected to the Z axis input of the cathode ray tube.