Abstract: Improved hydraulic fracturing compositions are disclosed which help reduce potential negative environmental impact by hydraulic fracturing. The disclosed compositions have flammability and toxicity and are relatively safe for the environment. The compositions may also contain biodegradable components.

Abstract: Improved hydraulic fracturing compositions are disclosed which help reduce potential negative environmental impact by hydraulic fracturing. The disclosed compositions have flammability and toxicity and are relatively safe for the environment. The compositions may also contain biodegradable components.

Abstract: Improved hydraulic fracturing compositions are disclosed which help reduce potential negative environmental impact by hydraulic fracturing. The disclosed compositions have flammability and toxicity and are relatively safe for the environment. The compositions may also contain biodegradable components.

Abstract: Improved hydraulic fracturing compositions are disclosed which help reduce potential negative environmental impact by hydraulic fracturing. The disclosed compositions have flammability and toxicity and are relatively safe for the environment. The compositions may also contain biodegradable components.

Abstract: Improved hydraulic fracturing compositions are disclosed which help reduce potential negative environmental impact by hydraulic fracturing. The disclosed compositions have flammability and toxicity and are relatively safe for the environment. The compositions may also contain biodegradable components.

Abstract: A cryogenic liquid heat exchanger system has a subatmospheric pressure reservoir, a tube, and an initial fluid ejector. The sub-atmospheric pressure reservoir has a vacuum exhaust. The tube extends through the reservoir. The initial fluid ejector has a suction chamber inlet that is functionally connected to the reservoir vacuum exhaust. The system may have a plurality of fluid ejectors connected to one or more exhausts either in series or parallel. The initial fluid ejector may receive one or more pressurized fluid streams, and the streams may be steam. A process for generating sub-atmospheric pressures in a cryogenic fluid heat exchanger reservoir includes the step of discharging an initial fluid stream into an initial fluid ejector having a suction chamber functionally connected to an exhaust of the reservoir. A process for generating sub-atmospheric pressures in a cryogenic fluid heat exchanger reservoir includes the step of using a fluid ejector to reduce the pressure in the reservoir.

Abstract: A system and method for cooling a first cryogenic liquid in a vessel comprises the steps of directing a second cryogenic into the first cryogenic fluid and releasing gas from the vessel. The first cryogenic fluid has a boiling point that is higher than the boiling point of the second cryogenic fluid. Directing the second cryogenic fluid into the first cryogenic fluid results in the second fluid cooling the first fluid and the second fluid vaporizing. The vaporized fluid is released as a gas from the vessel. The vessel may be a propellant tank for a space vehicle. The first and second cryogenic fluids are delivered from supplies located outside of the vehicle. The first cryogenic liquid may be oxygen and the second cryogenic liquid may be nitrogen, neon, or helium. In another aspect of the invention, the first cryogenic liquid may be hydrogen and the second cryogenic liquid may be helium.

Abstract: Slush is made from a liquid using slush making systems or according to slush making processes. A jacketed vessel of the processes and the systems has an interior wall that defines an interior space. The interior space comprises a top and a bottom. The interior space has an average overall cross-sectional area taken through a vertical axis extending generally between the top and the bottom. The interior space also has a collection portion having an average collection portion cross-sectional area taken through the vertical axis that is less than the average overall cross-sectional area. The liquid is placed into the interior space and the interior walls are cooled. Slush forms on the interior walls and migrates to the collection portion. The collection portion is located at the interior space bottom when the slush density is higher than the liquid density and the collection portion is located at the interior space top when slush density is less than the liquid density.

Abstract: A cryogenic propellant tank system and process for densifying cryogenic liquid propellant comprises a tank with a combined manifold, a combined manifold line, a pressurizing gas line, and a vent line. The combined manifold is located in the tank. The combined manifold line functionally connects the combined manifold to a chilling system. The pressurizing gas line and the vent line are also functionally connected to the combined manifold line. The tank may be disposed in a vehicle. The manifold is disposed proximate the top of the tank. The chilling system may be a heat exchanger/filling system. The process for filling the tank comprises the steps of charging the tank with cryogenic liquid propellant, venting gases in the tank, densifying the cryogenic liquid propellant, and pressurizing the tank. The tank is charged with the cryogenic liquid propellant such that the orifices in the combined manifold are submerged. The gases in the tank are vented through the combined manifold and out of the tank.

Abstract: Cutting tools for MIG (metal-inert gas) welders and conventional electric arc welders which provide clean and fast cutting action of ferrous and other oxidizable materials using only a directed stream of oxygen after cutting is initiated. For MIG welders, the cutting tool may be in the form of an attachment coming with or solid separately from the hand unit of the MIG welders. Such attachment is coupled to a source of oxygen and includes a manual control for the jet of oxygen used to oxidize and thereby cut the metal. To initiate the cutting action, an electric arc is first established for a short time to sufficiently locally heat the metal so that rapid oxidation will proceed without any further outside source of energy.

Abstract: A self-propelled combine has a series of rotary paddles for moving the crop rearwardly along the feeder housing from the platform to the combine separation system. The paddles are driven by a series of interconnected chain drives on the side of the feeder house, each drive including a chain trained around sprockets on the adjacent paddle shafts, and each drive is provided with an adjustable idler to vary the chain tension. Each idler includes a hexagonal shaft mounted in a support for adjustment normal to the shaft axis, and a ball type bearing is mounted on the shaft, the bearing having an inner periphery conforming to the shaft cross section so that it is axially slidable but nonrotatable thereon. The outer race of the bearing is provided with a sprocket that engages the drive chain, and the idler shift freely shifts along the shaft within limits to stay in alignment with the driven and driven sprockets.

Abstract: A self-propelled combine has a forward transversely elongated harvesting platform mounted on the forward end of a forwardly and downwardly inclined feeder housing through which the crop is fed to a separating mechanism in the combine body. A plurality of axially transverse paddle type impellers are mounted in the feeder housing and extend between the opposite sides of the housing immediately above the housing floor, the impellers being rotated in the same direction so that the impeller paddles move rearwardly along the floor, whereby the crop material is engaged by successive paddles and moved upwardly and rearwardly along the housing floor to the separating mechanism.