Abstract: The invention provides an apparatus for measuring microgravity acceleration that includes an elongate flow chamber having a first end and a second end and a liquid contained therein. Each end of the chamber is engaged by a plug member that is positioned to block the flow of the liquid through the ends of the container. Each plug member is maintained at a different known temperature such that a temperature gradient is created across the flow chamber. Temperature sensors are immersed in the liquid, the sensors being spaced apart along a line intersecting the axis of the flow chamber and normal thereto. Quasi-steady components of acceleration can be calculated based on the difference in the temperatures measured by the temperature sensors.

Abstract: Process and apparatus for growing crystals using float zone techniques. A rod (34) of crystalline materials is disposed in a cylindrical container (36), with a space being left between the rod and container walls. The space is filled with an encapsulant (72), selected to have a slightly lower melting point than the crystalline material. The rod is secured to a container end cap (38) at one end and to a shaft (60) at its other end. A piston (64) slides over the rod and provides pressure to prevent loss of volatile components upon melting of the rod. Prior to melting the rod the container is first heated to melt the encapsulant, with any off-gas from this step being vented to a cavity behind the piston. The piston moves slightly forward owing to volume change upon melting of the encapsulant, and the vent passageway (74) is closed. The container is then moved longitudinally through a heated zone (32) to progressively melt sections of the rod as in conventional float zone processes.

Abstract: A crystal growth apparatus (10) having a heated spherical growth container (12) is filled with a crystalline material in solid or liquid form. The crystalline material is heated by resistance heating wire (58) to a predetermined temperature, whereupon the application of heat to the crystalline material is reduced and the accumulated heat is drawn off and dissipated by a seed crystal (76) attached to a rod (70) of heat conductive material, which in turn is attached to a heat dissipating member (72). This results in the formation of a single, defect-free crystal on seed crystal (76), which grows outward in a generally spherical configuration as more heat is removed.

Abstract: A wake shield space processing facility (10) for maintaining ultra-high levels of vacuum is described. The wake shield (12) is a truncated hemispherical section having a convex side (14) and a concave side (24). Material samples (68) to be processed are located on the convex side of the shield, which faces in the wake direction in operation in orbit. Necessary processing fixtures (20) and (22) are also located on the convex side. Support equipment including power supplies (40, 42), CMG package (46) and electronic control package (44) are located on the convex side (24) of the shield facing the ram direction. Prior to operation in orbit the wake shield is oriented in reverse with the convex side facing the ram direction to provide cleaning by exposure to ambient atomic oxygen. The shield is then baked-out by being pointed directed at the sun to obtain heating for a suitable period.

Abstract: Apparatus and method for forming ultrapure glass rods (13) or fibers (28) from a polycrystalline rod (11) in which the method comprises the steps of heating a selected short section of the rod in the first furnace (21) to form a molten zone of the rod, heating a second selected short section of the rod in a second furnace (19) which initially is separated from the first furnace by a very short gap to form a second molten zone of the rod which initially is contiguous with and part of the first molten zone of the rod to form a single molten zone 14, and then gradually moving the first and second furnaces apart to first form a rod (13) and then, ultimately, a fiber (28), of ultrapure glass in the increasingly widening gap forming therebetween.

Abstract: Apparatus and method for pulling optical glass fibers in a containerless environment is disclosed which includes a single-axis acoustical levitation furnace (10) in which a specimen (S) is levitated and melted. A reflector unit (16) is carried in the interior of the furnace and includes a reflector (16a) disposed centrally about the acoustical axis of the levitator. The reflector unit includes a circular shroud (32) of insulation and a copper sleeve (34) inserted in the unit which is hollow at (34a) for receiving a cooling medium (38). A fiber pulling bore (40) is formed centrally in the reflector unit surrounded by cooling jacket (34a) to enhance solidification and formation of a fiber (F). A starting fiber strand is introduced into the melt and pulled outwardly through bore (40) whereby the specimen fiber is started and formed as pulled therethrough.