Abstract: An air-sampling cartridge is disclosed for collecting organic compounds such as N-nitrosamines from air for analysis. The cartridge is formed by joining two injection-molded plastic parts: a generally cylindrical cartridge body into which air-pervious packings of granular adsorbent materials may be loaded, and a cartridge cap which is ultrasonically welded to the body to partially close one end of the cartridge. The cap and body define a cartridge with an inlet and outlet shaped to facilitate connection of the cartridge to a pump used to draw air samples through the cartridge, to allow connection of two or more cartridges in series, and to accommodate standard-sized syringes used in removing trapped compounds from the cartridge for analysis.The cartridge also includes a retention clip integrally molded with the cartridge body and cap for permitting the cartridge to be attached to the clothing of a person during air-sampling.

Abstract: A boiler for heating liquid which combines a source of hot gases directed first along the inner wall of an annular tank in a tortuous path formed by fins disposed upon the inner wall and then along the outer wall of the tank through a jet-impingement heat transfer system.

Abstract: A heat pipe deicing system is disclosed for preventing accumulation of ice on portions of structures such as the deck, handrails, and ladders of a fishing vessel operating in very cold oceans. The heat pipe includes an evaporator in contact with a source of heat such as exhaust gases of an engine, one or more condensers positioned above the evaporator to cover surfaces to be deiced, and an insulated transition section for transporting a heat transfer fluid between the evaporator and condenser. The transition section and condenser have legs arranged to provide multiple passageways which assure continuous gravity-assisted return flow of condensed heat transfer fluid to the evaporator and a high level of deicing capacity even during pitching and rolling of the structure on which the deicing system is installed.

Abstract: A method and apparatus are disclosed for extracting N-nitroso compounds from air samples without artifact formation of nitrosamines from precursors in the sample. The apparatus includes a cartridge having two zones between a first port and a second port. The first zone, closest to the first port, contains an air pervious packing of a granular, solid phase amine complexing agent. The second zone, closest to the second port, contains an air pervious packing of a mixture of a granular, solid phase amine complexing agent and a particulate sorbent adapted to extract and concentrate N-nitroso compounds from air. The method includes a first step of driving an air sample through the first and second contiguous zones of the cartridge in succession, and a second step of driving an eluent through the second and first zones in succession, or backflushing the cartridge.

Abstract: Apparatus is disclosed for mechanically assisting circulation of blood in a patient for periods of up to a week or two until the patient's heart strengthens sufficiently to take over the full workload. The circulatory assist device includes a valveless pump with a flexible bladder, a pneumatic driver for applying pressure pulses to the bladder, and a single flexible conduit for conveying blood between the patient and the pump. In use the pump and driver are mounted external to the patient's body and the flexible conduit is connected to the pump and in end-to-side relationship with a major blood vessel on that side of the heart, either right or left, which is in need of support.

Abstract: A furnace for heat treating metal slabs or strips includes a heating chamber through which stock is passed in confronting relationship to an array of jet impingement radiation burners. Combustion is separated from the stock by flat refractory plates having a plurality of holes uniformly distributed thereover which direct uniform jets of combustion products upon the strip or slab. The jets of combustion products heat the work by convection. Also, the refractory jet forming plates are heated to radiance so that heat energy is transferred to the work by radiation.

Abstract: A solar collector is described in which air passed through the collector is heated by exchanging heat with a plate which absorbs solar energy. The collector includes a lightweight frame of rectangular cross-section having an inlet and outlet for passage of air, with the top of the frame sealed by a light-transmissive cover such as a sheet of glass. Also included in the collector are an absorber plate mounted in the frame below the cover, and a jet plate spaced a prescribed distance below the absorber plate. One or both of the plates is corrugated, and holes are provided in the jet plate at locations where the gap between plates is a minimum so that during operation of the collector, jets of air are directed through the holes and impinge on the lower surface of the absorber plate to produce efficient heat transfer, while channels defined by the corrugations facilitate flow of the spent jets to the collector outlet with minimal interruption of downstream jets.

Abstract: Methods and apparatus for removing compounds from air to clean the air and for providing quantitative analysis of the content of particular organic compounds in the air. Apparatus is described having a separation zone packed with a magnesium silicate or calcium silicate material in the form of finely divided particles which are effective in trapping and holding substantially all of certain predetermined compounds present in air passed through the material. The silicate-packed separation zone may be employed as a highly efficient filter to purify air containing pollutants or contaminants. Also described are a method and apparatus for accurately determining the content of predetermined organic compounds in a sample of air using a collection tube containing a sorbent material such as dry, finely divided activated magnesium trisilicate.

Abstract: A creping doctor in which a long, thin blade is applied to a roll surface at an angle to the tangent at the line of contact such that the blade presents a wide surface to the product being removed from the roll. A preferred angle is approximately normal to the surface, so that the roll surface tangent and the wide blade surface receiving the product make an angle ranging between acute and obtuse. A bladeholder provides both coarse and fine compliance of the blade to roll surface contour variations. Blades incorporating resilient means distributed along the back edge for cooperating with the bladeholder are also described.

Abstract: A vapor engine including a cylinder in which a piston reciprocates and having an inlet valve in the cylinder head which is driven from its seat by the piston as it approaches the cylinder head. The time at which the valve is driven from its seat does not change relative to the top dead center position of the piston. The travel of the valve body is ballistic and the valve remains open for a time determined by a combination of the piston velocity at the initial contact, the distance the valve travels before hitting a stop from which it rebounds elastically toward its seat, the pressure drop across the valve and the mass of the valve. The exhaust valve of the engine may be either internal and actuated by mechanical forces or external, in which case it is actuated by pressure forces. In one embodiment of the invention the stop from which the valve rebounds may be adjustably positioned manually or automatically to control the period of time during which the intake valve is open.

Abstract: A pneumatic pump adapted primarily as a left ventricular heart assist device includes a flexible bladder with a rigid housing. A pneumatic driver applies rhythmical pulses between the bladder and the housing to repetitively collapse the bladder and establish a pumping action through the bladder, in conjunction with check valves in the inlet and outlet to the bladder. Between the driver and the pump there is provided a pneumatic pulse limiter which includes a flexible diaphragm isolating the driver from the pump. Pulses from the driver are transmitted to the pump only through the flexible diaphragm and the diaphragm is constrained to move only within established limits. Regardless of the magnitude of the pulse from the driver, the maximum pulse applied to the pump cannot exceed that corresponding to the maximum displacement of the diaphragm.Between successive pulses, the portion of the system between the driver and the flexible diaphragm is depressurized.

Abstract: Rubbery reaction products of an aliphatic organic diisocyanate, a high molecular weight polyether polyol (poly tetra methylene ether glycol), a low molecular weight glycol chain extender and a polyhydic alcohol crossliker such as trimethylol propane. The resulting polymers have improved thromboresistant properties and a long flexural life.Bladders for heart pumps may be formed from the resulting polymer, and a novel process for forming bladders for heart pumps is disclosed.

Abstract: A prosthetic blood conduit comprises two porous concentrically associated tubes with a helical spring enclosed therebetween. Spring strength and frictional engagement between the spring and tubes enables the conduit to resist collapse under a wide variety of stress forces. Convolutions in the tube walls provide flexibility without kinking.

Abstract: A drainage foil providing improved fines retention and drainage stability when used in cooperation with the forming wire of a machine that forms a mat or web from a wet slurry. The foil has two wire-contacting surfaces a fixed distance apart with a suction-forming section and a drainage section between them. Forces effective on the foil during use are balanced so as to minimize torque around the foil mounting means.

Abstract: A rigid prosthetic blood vessel includes a plurality of interchangeable tubular sections. Various sections are straight and curved and have common interconnection means including both fixed and rotatable joints. End structures are included for connecting the prosthesis to various blood carrying vessels and organs.

Abstract: A method by which in vivo N-nitroso compounds are detected. The N-nitroso compounds appear in the metabolic system or are formed therein from one or more precursors. The metabolic reactions are terminated instantly at a predetermined point in time, as by freezing in a liquidied gas, and the frozen sample is analyzed for the presence of N-nitroso compounds.

Abstract: A heat exchanger for directing discrete jets of fluid against a heat exchanging wall is configured to establish relatively close spacing between the openings through which the jets are formed and a portion of the heat exchanging wall while providing relatively large volumes of space adjacent other portions of the heat exchanging wall. The large volumes of space permit passage of the fluid from adjacent the heat exchanging wall without disturbing the jet flow.

Abstract: A compact blood pump includes a flexible bladder mounted within a rigid metal housing. Pneumatic pulses between the bladder and the housing produce pumping action in association with appropriate inlet and outlet valves. The bladder is configured to provide a stiffness characteristic which produces a recurring three lobe collapse pattern during pumping operation. Inlet and outlet passages to the bladder are associated with detachable seal rotatable fluid conduits in fluid-tight relationship to the bladder. The conduits are attachable and rotatable without transmitting torque to the flexible bladder.

Abstract: A radiant tube burner mixes liquid fuel and/or gaseous fuel with air for combustion in a radiant tube to produce a quiet and stable luminous flame through the entire length of the radiant tube. A flame holding plate is positioned within the radiant tube to define a feed zone and a combustion zone. A liquid fuel nozzle positioned centrally in the plate directs fuel through the plate and into the combustion zone. The plate defines a series of apertures circumscribing the nozzle and another passage outward from the series of openings and concentric therewith. Combustion air is proportioned and admitted to the combustion zone through the series of openings and the passage. Gaseous fuel may be admitted to the combustion zone through the series of openings.

Abstract: A food cooker is illustrated in the form of a deep-fat fryer, in which the fat is isothermally heated to an operating temperature below a temperature range in which an unacceptably high rate of undesirable decomposition products formation occurs in the cooking liquid. The heat transfer process used is vaporization and condensation of a confined liquid essentially isothermally and substantially at the working temperature. Condensation of the heat transfer vapor takes place at an outer surface of the container for the fat. Heat is applied to the heat transfer liquid remote from the container, which having no heating element or elements intruding into its interior is easy to clean. Heat is transferred to the cooking fat by condensation of the heat transfer vapor essentially only as it is used by the load being cooked. Hot spots are minimized, so that the formation of undesirable decomposition products of the cooking fat is retarded.