Abstract: A power supply for electric arc welding, particularly gas tungsten arc welding, is described. The supply operates from conventional, alternating potential, and provides either a direct current or an alternating current with a rectangular wave shape to a load. The supply includes an input transformer, and two current paths, each of which includes an inductor and a controlled rectifier. A control circuit initiates conduction of the rectifiers at appropriate times selected to obtain the desired load current. In preferred embodiments, the control circuit includes differential amplifiers which enable comparison of the output current to a control current, adjustment of the ratio of the currents in the two current paths, and adjustment of the gain and time constant of the control circuit.

Abstract: An ultrasonic flowmeter which measures gas velocity including a pair of ultrasonic transducers oppositely located around a conduit at a predetermined angle to the flow direction. Each transducer alternates between acting as a transmitter and a detector of ultrasonic frequencies, thus as one transducer transmits, the other receives. A measurement is made of the time of flight of the ultrasonic signal between the transmitter transducer and the receiver transducer and a microcomputer calculates the velocity of the gas by a known mathematical relationship utilizing the difference between the time of flight of the ultrasonic signals traveling upstream and those traveling downstream. The time of flight is determined by the phase shift or difference in phase angle between the signal at the transmitter transducer and the signal detected by the receiver transducer. To prevent ambiguity arising when the phase angle difference exceeds 360.degree.

Abstract: Nb wire and Sn plated Cu wire and/or Sn plated Cu foil strip are fabricated into a composite that is mechanically worked to form a multifilament superconductor precursor that does not require intermediate anneals and that has required amounts of Sn distributed throughout its cross section for efficient reaction with the Nb filaments.

Abstract: A vapor component of a gas mixture is separated by condensation and is recovered for further use. A solvent vapor mixed with inert gas is condensed in a multistage heat exchange system in a manner which utilizes a first refrigerant to condense a portion of the vapor in a first heat exchange device, a second refrigerant, typically cold inert gas, for condensing a further portion of the vapor in a second heat exchanger and a third heat exchange device wherein the liquid phase of the inert gas (i.e. cryogenic liquid) is supplied to provide a source of refrigeration. In this latter heat exchange device, the cryogenic liquid is introduced into a body of condensed vapor thereby chilling such condensed vapor and stirring the same to avoid freezing. Chilled, condensed vapor is removed from the latter heat exchange device and is returned as a reflux thereto to condense the vapor component of the gaseous mixture supplied thereto.

Abstract: Method and apparatus for separating gases having different partial pressures at a given temperature includes introducing a multi-component gas mixture into a chamber, reducing the temperature therein to solidify and liquefy all components. At least one component remains liquid which is evaporated, thereby separating such component from the solidified components which may then be liquefied and recovered. The process is especially useful in recovering radioactive krypton and xenon from the off gas streams of nuclear processes such as nuclear fuel reprocessing.

Abstract: An improved method for manufacture of multifilamentary superconductors of the A.sub.3 B type having the A-15 crystal structure, such as Nb.sub.3 Sn, is disclosed in which rods or wires of the A material are disposed throughout a matrix consisting of Cu and the B material in substantially elemental form. The matrix is formed by compaction of powders of Cu; powders of the B may be mixed therewith or the B material may be infiltrated into pores between the individual Cu particles after compaction. The resultant composite has A, B and Cu distributed uniformly throughout its volume and can be worked to any desired final shape and size for heat treatment to form the A.sub.3 B material without intermediate annealing steps.

Abstract: Tobacco impregnated with solid carbon dioxide is heated in a chamber to expand the same by sublimation of solid CO.sub.2 and expulsion of CO.sub.2 gas from the tobacco. The expanded tobacco is separated from the internal atmosphere of the expansion device and the tobacco is discharged through an outlet through which gas flows are substantially precluded. The evolved CO.sub.2 gas and other volatile components are removed from the chamber and a portion of the removed gas is heated and returned to the chamber as the expansion medium. The necessity for external steam is avoided as an atmosphere of high thermal diffusivity is maintained in the expansion chamber by precluding the entry of ambient air.

Abstract: Refrigeration is produced by passing liquid carbon dioxide through a narrow slot into an enclosure or conduit having an inlet and an outlet in communication with ambient atmosphere. Liquid carbon dioxide is converted to solid and gaseous phases upon passage through the slot to produce a refrigeration effect and such phases are directed toward the enclosure exit thereby entraining ambient atmosphere in the solid and gaseous stream. This entrainment and mixing is effective to cause a relatively rapid sublimation of the solid carbon dioxide after exiting the enclosure and thus permits uniform refrigeration of a chamber into which the solid and gaseous carbon dioxide is discharged.

Abstract: A motor-driven rotating table positioning device has a bullgear engaged by two pinions each driven by the high-efficiency worm and gear set. These two worm and gear sets are connected by a coupling shaft and an adjustable coupling which allows a desired torsion to be maintained in the coupling shaft thereby eliminating any table backlash caused by the bullgear, pinions and high-efficiency worm and gear sets. For safety in the event of motor failure, the motor is coupled to the coupling shaft by a low-efficiency or self-locking worm and gear set.

Abstract: Processes for the preparation of certain halogenated aliphatic ethers are described, and in particular the preparation of 1,1,2-trifluoro-2-chloroethyl methyl ether, i.e., CH.sub.3 OCF.sub.2 CHFCl. This particular ether has many uses, and is a valuable material for use in the production of the inhalant anesthetic enflurane, 1,1,2-trifluoro-2-chloroethyl difluoromethyl ether, i.e., CF.sub.2 HOCF.sub.2 CHFCl, made and sold under the trademark ETHRANE by Airco, Inc., Montvale, New Jersey 07645.

Abstract: A thoracic drainage unit for removal of fluids from the thoracic cavity of a patient and/or to assist a patient in breathing comprises a collection chamber for receiving the fluids from the patient and an underwater seal located between the collection chamber and the patient. The underwater seal prevents pressure being applied to the thoracic cavity or backflow to that cavity. The water or other liquid for the seal is provided with the collection chamber as a complete unit ready for use. A collapsible bottle has a breakable neck that is readily broken by the user, whereupon the bottle is collapsed to force the liquid therein to create the liquid seal. A baffle is provided to prevent the liquid from reentering the bottle as it reexpands so that the precise needed volume of liquid is retained to create the seal.

Abstract: The rate of calcining carbonaceous material in a rotary kiln is increased by enriching with oxygen air supplied into the kiln by fans. The introduction of oxygen is effected during a predetermined portion of each kiln revolution and is effective to enrich the oxygen content of air supplied to the kiln to approximately 23-25% oxygen. By so enriching the interior kiln atmosphere during calcining of material such as petroleum coke, greater temperatures are obtained than will be obtained by the use of air alone thereby accelerating the evolution of volatile materials and the combustion of such volatiles during calcination. The accelerated evolution and combustion of volatiles enables the rate at which carbonaceous material is calcined in a kiln of a given length to be increased.

Abstract: The rate of calcining carbonaceous material in a rotary kiln is increased by introducing oxygen into the inlet of air fans mounted on the kiln. The introduction of oxygen is effected during a predetermined portion of each kiln revolution and is effective to enrich the oxygen content of air supplied to the kiln to approximately 23-25% oxygen. By so enriching the interior kiln atmosphere during calcining of material such as petroleum coke, greater temperatures are obtained than will be obtained by the use of air alone thereby accelerating the evolution and combustion of volatile materials during calcination. The accelerated evolution and combustion of such volatiles enables the rate at which carbonaceous materials can be calcined in a kiln of a predetermined length to be increased.

Abstract: Process for adjusting the halogen content of halogenated aliphatic ethers, by selective replacement of a halide substituent on the ether with a hydrogen. The process is particularly useful for the production of certain inhalant anesthetics.

Abstract: The degree of saturation of a vapor in a chamber such as a curing oven is controlled by sensing the vapor dew point and varying the rate of removal of such vapor from the oven in response to a comparison of the sensed dew point with a predetermined dew point. This comparison may also be effected by comparing the difference between the actual dew point and oven temperature with a predetermined difference and controlling the rate of vapor removal in response to variations between the actual and predetermined differences. Alternately, a predetermined ratio between dew point and oven temperature may be maintained. By controlling the dew point of the vapor, i.e. degree of saturation, condensation in the oven is precluded while still permitting high solvent vapor concentrations which in turn facilitate recovery of solvent exhausted or removed from the oven.

Abstract: A counterbalance mechanism is disclosed for offsetting the normal gravitational forces exerted on a rotatable cylindrical hood for an incubator. The mechanism includes a specially shaped cam that is fixed with respect to the rotatable hood. A cam follower, mounted on a slide movable with the rotatable hood, is spring biased against the cam. As the rotatable hood is moved to various positions, the spring loading and cam profile coact to produce a counter-rotational force that is opposite and equal to the force of gravity acting upon the hood at any point in its rotation. One or more detents is provided in the cam at predetermined positions such that the cam follower can be positioned within one of the detents at one or more desired positions of hood rotation such that the hood may be held at that selected position.

Abstract: Methods for the dehalogenation of various haloethers are disclosed, comprising providing a haloether having the formula CX'.sub.3 -[CY.sub.2 ].sub.n -O-CZ.sub.2 -CX.sub.3 in which X', Y, Z and X are specifically disclosed combinations of hydrogen, fluorine chlorine and bromine such that the molecule includes at least one reducible group, but where both portions of any ethyl groups present are not reducible. Dehalogenation of these haloethers is carried out by contacting same with a hydrogen donor comprising an amine, preferably a primary or secondary amine or a primary, secondary or tertiary alkanol amine. The amine is preferably used in combination with a catalyst, such as a varivalent metal or a salt thereof, such as copper or a copper salt.

Abstract: An improved infant incubator is disclosed having a cylindrical shaped transparent hood which provide considerable accessibility to the infant. The cylindrically shaped hood consists of a plurality of sections rotatable about a central axis. The sections may be individually opened to give limited access to the infant or totally rotated to a position beneath the infant support structure such that access may be had from all sides of the incubator without obstructions. Heating of the incubator compartment is achieved by a unique means of circulating heated air through a double wall construction of the hood. The air is heated in a compartment beneath the infant and the warm air enters one of the hood sections and circulates through that section whereupon it is transferred serially to the next section and eventually can be received back into the heater compartment from the hood sections for recirculation. A fan and heater are located in the heater compartment for heating and circulating the air.

Abstract: A membrane and the method of making the same is disclosed for use with glucose analyzers to detect the level of glucose in liquid mediums such as whole blood. The membrane comprises a thin base wafer of a hydrophobic fluorocarbon material such as polytetrafluoroethylene (TEFLON). The wafer is initially etched by removing surface fluorides to produce a hydrophilic surface and is then contacted with a mixed reagent formed by combining in a volume ratio of about 1:1:1 about 4% paraformaldehyde in water, about 5% bovine serum albumin in water and about 10% glucose oxidase in water. The resultant membrane contains glucose oxidase covalently bonded to the surface of the base wafer.

Abstract: A device for use in vacuum suction systems for withdrawing fluids from a patient's body cavity, such as the stomach, wherein the device includes a chamber that is located in the flow stream of such fluids between the patient and the source of vacuum. At predetermined intervals, the device forces a quantity of the withdrawn fluid from the chamber, back into the suction tubing leading to the patient such that some of the fluid previously removed from the body cavity is forced backward toward such cavity under a positive pressure to dislodge any obstructions that may have occurred in the tubing or at the end of such tubing. In the preferred embodiment, the device is effectively self-contained and needs no source of positive pressure or electricity for its operation and is readily and fully operable from present commercial intermittent suction systems without revamping or otherwise modifying existing systems.