Abstract: An endotracheal tube holder comprises a substantially straight projection having a laterally curved, trough-like surface mounted on a base for securing said projection to a person's head such that the projection is adapted to receive in longitudinally aligned relation the protruding end of an endotracheal tube in its applied working position. A pair of laterally opposed tabs at the outer end of the projection serve as stop lugs for preventing a wrapping, such as tape, which binds the tube to the projection from sliding off the projection.

Abstract: The N-nitrosoamine content of a sample is measured by breaking the N--NO bond in the N-nitrosoamine molecule so as to liberate nitric oxide and thereafter measuring the amount of nitric oxide liberated.

Abstract: Low pressure steam generated by a solar collector is compressed to raise its temperature and pressure. The compressor is driven by an engine which is, in turn, driven by a combustible fuel. Shaft work produced from the fuel is used directly to drive the compressor. The energy available from the steam is the sum of that resulting from both solar energy and combustion of fuel. The total amount of steam produced per Btu of heat generated by fuel input to the engine is substantially greater than the amount of steam that would be produced directly by combustion of the fuel.

Abstract: A miniature unidirectional condenser microphone includes a diaphragm dividing a housing into first and second chambers. Each chamber communicates through a sound inlet port to the atmosphere. One of the sound inlet ports is covered by a sheet of porous, non-absorbent, hydrophobic thermoplastic material forming an acoustical resistance.

Abstract: Apparatus disclosed herein provide simple means for observing chemiluminescent reactions and for measuring the concentrations of several constituents of a gaseous sample substantially simultaneously, as for example the concentrations of NO.sub.x, NO and NO.sub.2 in a mixture of other gases. Chemiluminescence is induced by the spontaneous reaction of selected constituents with reagents in a plurality of small reaction chambers confronting a single sensitive photodetector. The reation chambers utilize concentric feed nozzles to enhance the intimate mixing of reactants to promote more complete and rapid reaction near ambient pressure in a minimized space.

Abstract: A peak ventilatory flow rate indicator includes a hollow tube open at each end and has a series of small graded openings which hold a liquid by surface tension. When a subject ventilates his lungs through the tube as rapidly as possible, the number of graded openings from which the liquid is expelled is a function of peak ventilatory flow rate and an indication of pulmonary function.

Abstract: A spectrophotometric method is disclosed for measuring the heating value of a mixture of substances commonly comprising a gaseous fuel. The method is based on the recognition that within certain wavebands the mixture exhibits a correlation between heating value and the strength of radiant energy absorption. A spectrophotometric apparatus is disclosed which is adapted to permit the continuous observation of the heating value of the mixture.

Abstract: Food preparation apparatus involves a heat transmitting zone and a heat source located remotely from the transmitting zone. Heat energy is transferred from the heat source to the transmitting zone by a fluid vapor which travels from the heat source to the transmitting zone, condenses upon the transmitting zone and then returns in a liquid state to the heat source.In one described embodiment of this invention, an oven is provided wherein a fluid enclosure within the oven walls confines the vapor which transfers heat energy from a central heat source to heat transmitting surfaces.

Abstract: A vacuum furnace heats articles by radiation from a condenser portion of a heat pipe. The heat pipe further includes an adiabatic portion passing through the enclosing wall of the furnace and an evaporator portion outside the enclosure. The evaporator portion is preferably heated by a gas-fired burner which may surround it, and the heat pipe acts as a flux converter accepting heat outside the enclosure and delivering heat inside the enclosure to the articles to be heated. The condenser portion of the heat pipe may be panel-shaped and is disposed adjacent the articles to be heat-treated. In the more elaborate forms of the invention involving condenser panels, the condenser panel, or each condenser panel where several heat pipes are used, is a cylindrical section which partially, or substantially completely, surrounds the articles.

Abstract: An external combustion engine, such as the vapor cycle engine, produces power by the expansion of a working fluid vapor. A vapor generator vaporizes a suitable working fluid which is fed to an expander. The vaporized working fluid expands and is subsequently fed back to the vapor generator. A burner provides energy for the vapor generator. The fuel and air supply for the burner is controlled by a system responsive to operating conditions of the engine. That is, the power input to the vapor generator is correlated by a control system with the demand on the engine. The control system disclosed involves a servomechanism which may suitably respond, for example, to either the working fluid flow rate or the input from an accelerator which commands a change in the working fluid flow rate.

Abstract: A closed vapor cycle engine which uses a trifluoroethanol working fluid improved by the addition of ammonia for corrosion protection. The working fluid may contain water. The improvement improves life and reduces maintenance of the engine.

Abstract: An energy source for a heat-utilizing device which includes a source of gamma radiation, an absorber of such radiation and a heat-utilization device in heat-transfer relationship with the absorber of gamma radiation. The enclosure of the energy source is so constructed that additional heat-utilizing device may also be energized from the same source of gamma radiation.