Abstract: A safety valve (14) adapted to be inserted within a flowline (10) comprises an elongate valve body (16) having central bore (24) with a fluid inlet (40) and a fluid outlet (42) in fluid communication with the bore (24). A slidable valve element (50) having a fluid passage (62) therein is mounted within the bore (24) and is slidable between the seated and unseated positions. A stop member (108) is mounted on the valve body (16) for relative movement between extended and retracted positions and has a stem which extends within the bore (24) along the longitudinal axis of the valve body (16). During normal operation valve element (50) is in a seated position and stop member (108) is in a retracted position, and thus, fluid flows from the fluid inlet (40) to the fluid outlet (42).

Abstract: A method for assaying a cell culture for mutagenesis is described. A cell culture is stained first with a histochemical stain, and then a fluorescent stain. Normal cells in the culture are stained by both the histochemical and fluorescent stains, while abnormal cells are stained only by the fluorescent stain. The two stains are chosen so that the histochemical stain absorbs the wavelengths that the fluorescent stain emits. After the counterstained culture is subjected to exciting light, the fluorescence from the abnormal cells is detected.

Abstract: Method and apparatus for spreading and angle-encoding each pulse of a multiplicity of small area, short pulses into several temporally staggered pulses by use of appropriate beam splitters, with the optical elements being arranged so that each staggered pulse is contiguous with one or two other such pulses, and the entire sequence of stacked pulses comprising a single, continuous long pulse. The single long pulse is expanded in area, and then doubly passed through a nonstorage laser amplifier such as KrF. After amplification, the physically separated, angle-encoded and temporally staggered pulses are recombined into a single pulse of short duration. This high intensity output beam is well collimated and may be propagated over long distance, or used for irradiating inertial confinement fusion targets.

Abstract: A gate valve (10) has an expanding gate assembly (34) for reciprocal movement transversely of the flow passage (16, 18). The expanding gate assembly (34) includes a gate element (68) and complementary segment (70) which expand away from each other when the gate assembly (34) is in either a fully open or closed position. A spring (92) is anchored to a side (87) of the gate element (68) and extends over and engages a pair of spaced apart lugs (88, 90) on the adjacent side (91) of the segment (70). The lugs (88, 90) are positioned so that the movement of the gate element (68) relative to the segment (70) from the fully collapsed position results in the spring (92) exerting at least seventy percent of its total force on the lug (88 or 90) that is leading with respect to the direction of relative movement of the segment (70).

Abstract: A gate valve (10) has an expanding gate assembly (34) mounted in the valve chamber (14) for movement between open and closed positions. The gate assembly (34) includes a gate (44) connected to a valve stem (28) and a segment (52) is carried by the gate (44). The gate (44) and segment (52) each have wedging surfaces (46 and 54) which permit a wedging action to provide lateral expansion therebetween at the open and closed positions. A rocker arm (80) is pivotally mounted to a side (49) of the gate (44). The rocker arm (80) has a slot (102) with a bearing block (104) slidably received therein. A bearing pin (110) extends from a side (57) of the segment (52) and is journaled in the bearing block (104). A seat skirt (60) is contained within the valve chamber (14) and engages the rocker arm (80) so as to control the ability of the rocker arm (80) to pivot about the gate (44) thereby allowing the gate (44) and segment (52) to expand from each other at a preselected position in the travel of the gate assembly (34).

Abstract: A catalytic cartridge surrounding a heat pipe driven by a heat source is utilized as a SO.sub.3 decomposer for thermochemical hydrogen production. The cartridge has two embodiments, a cross-flow cartridge and an axial flow cartridge. In the cross-flow cartridge, SO.sub.3 gas is flowed through a chamber and incident normally to a catalyst coated tube extending through the chamber, the catalyst coated tube surrounding the heat pipe. In the axial-flow cartridge, SO.sub.3 gas is flowed through the annular space between concentric inner and outer cylindrical walls, the inner cylindrical wall being coated by a catalyst and surrounding the heat pipe. The modular cartridge decomposer provides high thermal efficiency, high conversion efficiency, and increased safety.

Abstract: A steam separator (10) has a generally horizontal baffle plate (18) which separates the separator vessel (12) into an upper steam chamber (20) and a lower water chamber (22). The baffle plate (18) has a central opeing (51) which provides a flow passage to permit steam from the water chamber (22) to rise into the steam chamber (20). A steam outlet (28, 100) is connected to the vessel (12) for discharging steam from the steam chamber (20). The baffle plate (18) has a plurality of openings (62) at the periphery thereof, and each opening (62) has a scoop (60) associated therewith. Each scoop (60) extends over its respective opening (62) and faces in substantial opposition to the direction of motion of the swirling fluid to receive and direct the swirling fluid into the water chamber (22).

Abstract: A pilot line-operated control valve (32) for an actuator (14) that operates a gate valve (12) in the main flowline (10). A slide valve (70) having a piston (76) on its inner end is mounted in a longitudinal bore (46) of the elongate valve body (40) for movement between an open position in which fluid is directed to actuator (14), and a closed position in which fluid is prevented from flowing to actuator (14). A fluid isolated pilot blocking portion (98) of slide valve (70) is oriented such that once slide valve (70) moves to the closed position, pilot blocking portion (98) abuts pilot port (56) so as to block pilot line fluid pressure from acting on slide valve (70) under any operating conditions, including even a resumption of fluid pressure in the pilot line (30), when slide valve (70) is in the closed position. The so-called push-type control valve (32) is reset by manually pushing slide valve (70) inwardly.

Abstract: A valve seat structure for an expanding type gate valve (20). A valve seat (64) is received in each annular seat recess (62) formed around the upstream and downstream flow passages (24, 26) and opening to the valve chamber (22) wherein a gate assembly (32) is movable between open and closed positions. An annular face seal (82) is mounted within an annular groove (70) in the front seat face (66) of each valve seat (64). A substantial portion of the bottom (76) of the annular groove (70) comprises a frusto-conical bottom portion (80) which forms a wedging surface with a cone angle in the range of approximately 30.degree. to 60.degree. and disposed substantially coaxial with the groove sides and the flow passages. The rear seal face (86) of the face seal (82) has a frusto-conical rear portion (94) that conforms to the frusto-conical bottom portion (80). The annular groove (70) is wider than the thickness of the face seal (82 ) so that the face seal loosely fits within the annular groove.

Abstract: In an expanding gate valve, tangential pins (70) are received loosely in peripheral grooves (62) of floating valve seats (26) to prevent the seats from moving inwardly far enough to drag against a gate mechanism (32) which is collapsed for movement between open and closed positions of the valve. Alternative arrangements provide retainer rings (122, 130) which engage shoulders (128) of the seats to limit their inward floating movement.

Abstract: The occlusive cuff system of this invention comprises a pressure cuff and a source of regulated compressed gas feeding the cuff through an electrically-operated fill valve. An electrically-operated vent valve vents the cuff to the ambient pressure. The fill valve is normally closed and the vent valve is normally open. In response to an external start signal, a logic network opens the fill valve and closes the vent valve, thereby starting the pressurization cycle and a timer. A pressure transducer continuously monitors the pressure in the cuff. When the transducer's output equals a selected reference voltage, a comparator causes the logic network to close the fill valve. The timer, after a selected time delay, opens the vent valve to the ambient pressure, thereby ending the pressurization cycle.

Abstract: A valve seat assembly adapted to fit within an annular groove in a butterfly valve body. The seat assembly includes a pair of opposed metal seat rings generally L-shaped in cross section with overlapping outer legs seated and anchored in the bottom of the groove. The seat rings have flexible free inner end portions extending radially inwardly of the groove terminating at outwardly curled arcuate ends which contact the sealing surface of the valve disc and extend laterally of the groove in spaced relation to and over the adjacent valve body. A resilient soft seal is mounted between the metal seat rings and the sides of the metal seal rings are corrugated to grip and retain the soft seal in place.

Abstract: A seal assembly for sealing a variable gap between the surface of a first element and a second element movable relative thereto. A seal may comprise a seal housing attached to the second element for movement therewith and having a sealing surface thereon and at least one elongated seal member carried by the housing having first and second conjugate sealing surfaces thereon, the first sealing surface for rubbing and sealing engagement with the first element surface and the second sealing surface for sliding and sealing engagement with the housing sealing surface. A biasing assembly may be carried by the housing for biasing the first and second conjugate sealing surfaces of the sealing member toward sealing engagement with the first element surface and housing sealing surface, respectively.

Abstract: In a hydrazine powered engine, an intake valve arrangement for positively controlling the opening and closing of the poppet valve in a hot gas cylinder, the poppet valve being operated by the piston and gas pressure only. The poppet valve uses a pneumatic "spring" which holds the poppet valve against the piston while the valve is opened and closed. To accomplish this, a poppet valve is slidably mounted in a "pneumatic spring" chamber which reaches a pressure approaching the gas supply pressure and, during the opening of the valve, the "spring" chamber retains enough pressure to hold the poppet valve onto the piston. In addition, the bottom of the poppet valve can have a suction cup type configuration to hold the poppet valve on the piston during the down stroke.

Abstract: The object of this invention is to provide the method of altering the size of tetrafluoroethylene tubing which is only available in limited combination of wall thicknesses and diameter. The method includes the steps of sliding the tetrafluoroethylene tubing (12) onto an aluminum mandrel (20) and clamping the ends of the tubing to the mandrel by means of clamps (24). The tetrafluoroethylene tubing and mandrel are then placed in a supporting coil (25). The supporting coil with the mandrel and tetrafluoroethylene tubing are then positioned in a insulated steel pipe (28). The steel pipe is normally covered with a fiber glass insulator to smooth out temperature distribution therein. The entire structure is then placed in an oven which heats the tetrafluorethylene tubing which is then shrunk by the heat to the outer dimension of the aluminum mandrel. After cooling the aluminum mandrel is removed from the newly sized tetrafluoroethylene tubing by a conventional chemical milling process.

Abstract: Method and automated apparatus are disclosed for determining the time of detection of metabolically produced hydrogen by coliform bacteria cultured in an electroanalytical cell from the time the cell is inoculated with the bacteria. The detection time data provides bacteria concentration values. The apparatus is sequenced and controlled by a digital computer to discharge a spent sample, clean and sterilize the culture cell, provide a bacteria nutrient into the cell, control the temperature of the nutrient, inoculate the nutrient with a bacteria sample, measures the electrical potential difference produced by the cell and measures the time of detection from inoculation.

Abstract: A process for producing aromatic polyamides having improved nonflammability characteristics in which a polyamide substrate is contacted with a gaseous medium comprising a minor amount of a haloolefinic material and an inert diluent in the presence of light having sufficient energy to effect chemical addition of the haloolefin to said polyamide substrate.

Abstract: A delta modulation system with an encoder for encoding successive samples of an analog signal during successive sample intervals into a digital status change code signal indicating the difference between a sample and an estimate of the sample as one of three states: increasing, decreasing or unchanged in status. The status change code signal is transmitted to a decoder which reconstructs the analog signal from the digital status change signal. The status change code signal is also used in the encoder to estimate the next sample of the analog signal.

Abstract: A floating nut retention system includes a nut having a central aperture therein. An inner retainer plate has an opening therein, the nut being secured to the inner retainer plate with the nut aperture and the inner retainer plate opening being fixedly aligned therewith. An outer retainer member is formed of a base plate having an opening therein and having a surface adjacent a surface the inner retainer plate. The outer retainer member includes a securing mechanism for retaining the inner retainer plate adjacent to the outer retainer member. The securing mechanism enables the inner retainer plate to float with respect to the outer retainer member, while simultaneously forming a bearing surface for said inner retainer plate.

Abstract: A method and apparatus for removing porphyrins from a fluid sample which are unrelated to the number of bacteria present in the sample and prior to combining the sample with luminol reagent to produce a light reaction. The method involves a pre-incubation of the sample with a dilute concentration of hydrogen peroxide which inactivates the interfering soluble porphyrins. Further, by delaying taking a light measurement for a predetermined time period after combining the hydrogen peroxide-treated water sample with a luminol reagent, the luminescence produced by the reaction of the luminol reagent with ions present in the solution, being short lived, will have died out so that only porphyrins within the bacteria which have been released by rupturing the cells with the sodium hydroxide in the luminol reagent, will be measured. The measurement thus obtained can then be related to the concentration of live and dead bacteria in the fluid sample.