Abstract: The invention relates to a spray system for a multi-ingredient ablative material wherein a nozzle A is utilized for suppressing overspray. The nozzle includes a cylindrical inlet (12) which converges at (12a) to a restricted throat (13). A curved juncture (15) between cylidrical inlet (12) and convergent portion (12c) having a predetermined radius of curvature affords unrestricted and uninterrupted flow of the ablative material. A divergent bell-shaped chamber (14) and adjustable nozzle exit B is utilized which provides a highly effective spray pattern in suppressing overspray to an acceptable level and producing a homogeneous jet of material that adheres well to the substrate.

Abstract: Dye fading during archival storage of developed color photographic film (17) is retarded by placing the film in a sealed, opaque vault (10), introducing a dry, pressurized inert gas into the vault while the latter is vented, and sealing the vault after the air within the vault has been purged and replaced by the inert gas. Preferably, the gas is nitrogen; and the vault is stored at a temperature below room temperature to preserve the color photographic emulsions on the film contained within the vault. For short-term storage, sodium thiocyanate pads (36) charged with water are placed within the vault. For long term storage, the interior of the vault is kept at a low relative humidity.

Abstract: A biocentrifuge (10) is provided as part of a bioresearch centrifuge system (1) for subjecting caged animals to long term centrifugal forces that create gravity conditions aboard orbiting spacecraft. The centrifuge comprises a generally circular, rotatably mounted frame carrying a plurality of removable and replaceable cages (40) for the animal specimens. Pairs of opposing cages may be removed from the frame while it is rotating, by means of a cage exchanger (20) which rotates concentrically within the centrifuge and the speed of which is controlled independently of the frame speed. An image rotator (17) is provided for selective observation of the rotating animals. The system further includes a waste conveyor system (70), a food supply system (80) and a water supply system (90) for each cage for creating a life sustaining environment so that the animals can live in the rotating centrifuge for extended periods.

Abstract: Containerless high temperature calorimeter apparatus is disclosed for measuring high temperature thermophysical properties of materials which includes a unique containerless heating apparatus wherein the specimen is suspended and heated by electron bombardment.

Abstract: Monodisperse latexes having a particle size in the range of 2 to 40 microns are prepared by seeded emulsion polymerization in microgravity. A reaction mixture containing smaller monodisperse latex seed particles, predetermined amounts of monomer, emulsifier, initiator, inhibitor and water is placed in a microgravity environment, and polymerization is initiated by heating. The reaction is allowed to continue until the seed particles grow to a predetermined size, and the resulting enlarged particles are then recovered. A plurality of particle-growing steps can be used to reach larger sizes within the stated range, with enlarged particles from the previous steps being used as seed particles for the succeeding steps. Microgravity enables preparation of particles in the stated size range by avoiding gravity-related problems of creaming and settling, and flocculation induced by mechanical shear that have precluded their preparation in a normal gravity environment.

Abstract: A method for separating biological cells characterized by the steps of suspending a mixed cell population in a body of aqueous polymer comprising a system consisting of phases for which said cells exhibit an affinity including at least one phase having droplets characterized by a first surface potential and at least one phase having droplets characterized by another surface potential, and subjecting said system to an electrostatic field established between a pair of electrodes, said field being of sufficient intensity for causing at least some of the droplets to migrate toward one of said electrodes with an attendant separation of the cells of said population.

Abstract: A panel for selectively absorbing solar energy comprising an aluminum substrate, a layer of zinc thereon, a layer of nickel over the zinc layer and an outer layer of solar energy absorbing nickel oxide or a copper substrate with a layer of nickel thereon and a layer of solar energy absorbing nickel oxide distal from the copper substrate. A method for making aforesaid panels is disclosed.

Abstract: An improved solar concentrator characterized by a plurality of elongated supporting members arranged in substantial horizontal parallelism with the axis thereof intersecting a common curve and a tensioned sheet of flexible reflective material disposed in engaging relation with the supporting members for imparting to the tensioned sheet a catenary configuration.

Abstract: A passive propellant acquisition and feed system is disclosed which will acquire and feed gas-free propellant in low or zero-g environments during orbital maneuvers which will also retain this propellant under high axially directed acceleration such as may be experienced during launch of a space vehicle and orbit-to-orbit transfers wherein the propellant system includes a dual compartment propellant tank with independent surface tension acquisition channels in each compartment to provide gas-free flow of pressurized liquid propellant from one compartment to the other in one direction only.

Abstract: A radiation shadow indicator having a sight tube for sighting shadow-casting objects along a sighting axis. The indicator includes a system of gimbals mounting the tube for angular movement so that the sighting axis thereof may be caused to follow the apparent diurnal movement of celestial objects at various seasons of the year. Position indicators are provided for instantaneous read-out of angular positions of the gimbal device which, in turn, correspond to positions of the sighting axis at given seasons and/or times of day in relation to the location of the indicator on the surface of the earth.

Abstract: Zinc orthotitanate (Zn.sub.2 TiO.sub.4) suitable for use as a pigment for spacecraft thermal control coatings is prepared by heating a slightly zinc-deficient reaction mixture of precipitated oxalates of zinc and titanium. The reaction mixture can be formed by co-precipitation of zinc and titanium oxalates from chloride solution or by mixing separately precipitated oxalates. The mixture is first heated to 400.degree. to 600.degree. C to remove volatiles and is then rapidly heated at 900.degree. to 1200.degree. C. Zinc orthotitanate produced by this method exhibits the very fine particle size needed for thermal control coatings as well as stability in a space environment.

Abstract: This invention disclosure relates to the incorporation of a high nitrogenntaining compound selected from tetrazole and bitetrazole in the form of a doughnut forward of the nozzle throat or in the form of a toroidal ring attached to the aft end of the nozzle exit cone. Both have been demonstrated as an effective means of reducing the quantity of water in the exhaust plume to an acceptable level which does not impart adverse effects on sensors or cause a reactive effect on the graphite constituents of the rocket nozzle. The compound, bitetrazole or tetrazole, can also be incorporated into the solid propellant where it will function similarly as a means or mechanism for water removal from the exhaust plume. Because of its contribution to the propellant's performance through the generation of near-incompressible gases, N.sub.2, H.sub.2 and CO, it is a desirable propellant ingredient.

Abstract: Each of the parameters of objects in the field of view is measured and inidually compared with standard parameters. Differences in these parameters are multiplied by individual weighting factors and they are summed for each object. Object having the lowest sum is the desired target.