Abstract: Breathing apparatus is disclosed in which a selected portion of each exhalation is returned to the inlet side for rebreathing. The percentage of each exhalation rebreathed varies from exhalation to exhalation and is determined in accordance with the detected magnitude of the preceding inhalation. Breathing mixture is withdrawn by the user from a reservoir which is in communication with a cylinder having a spring loaded piston therein. The pressure in the reservoir, and hence in said cylinder, at the end of each inhalation determines the position of the piston. A chamber receives the exhaled breath and expands to a degree dependant on the position of the piston. Once the chamber has expanded to the maximum extent permitted for that exhalation, the remainder of the exhalation is discharged from the apparatus.

Abstract: Methods and apparatus are disclosed for directing a fluid spray against the interior surfaces of a reaction vessel, without the need for operating personnel to enter the vessel, employing orbiting nozzles connected by a conduit to an annular piston assembly all of which are contained in a cylinder housing mounted externally on the vessel. A hydraulic or pneumatic force is alternately applied to one of the piston surfaces, the rate and direction of movement of the piston, and hence the spray nozzles being controlled by the discharge of fluid from the cylinder housing on the opposite side of the piston. In one embodiment the hydraulic pressure used to drive the piston is provided by the same pressurized fluid which is used in the spraying operation.

Abstract: An improved method of determining the true swing weight of a golf club is provided by balancing the club at a fulcrum located under the shaft at a point approximately five inches from the tip of the grip end of the shaft. All of the golf clubs in a set are matched to each other on the basis of (a) total club weight; (b) the location of the club's center of gravity at a point on the shaft which is a constant distance from the tip of the grip end of each club; (c) true swing weight. This matching is accomplished while accounting for the effects of an additional component weight placed in the grip end of the shaft, displaced radially from the shaft axis. This additional component weight also produces a countering force to the torquing forces which act to resist the golfer's efforts to bring the club face into proper alignment for impact during the latter part of the downswing. This additional component weight also tends to counter the precessional forces on the head which develop during the swinging of the club.

Abstract: Urea is made from ammonia and carbon dioxide by first reacting ammonia and carbon dioxide to form urea, ammonium carbamate and water, and then decomposing the carbamate to ammonia and carbon dioxide which are returned to the reaction zone.