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Protective Solid Electrolyte Films for Thin Li-Ion Cells

These films would simplify fabrication and afford greater flexibility in design. Thin films of Li2CO3 are under consideration for use as passivating layers between electrodes and solid electrolytes in advanced thin-film lithium-ion electrochemical cells. By suppressing undesired chemical reactions as described below, the Li2CO3 films could help to prolong the shelf lives, increase the specific energies, and simplify the fabrication of the cells. Batteries comprising one or more cells of this type could be used as sources of power in such miniature electronic circuits as those in “smart” cards, implantable electronic medical devices, sensors, portable communication devices, and hand-held computers.

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Testing Soil for Electrokinetically Enhanced Bioremediation

Data from tests provide guidance for in situ treatment. The term “prefield test” denotes an in situ test of contaminated soil in preparation for in situ treatment of the soil by a method called “electrokinetically enhanced bioremediation” (EEB). A prefield test yields data that are helpful in designing and operating an efficient and cost-effective EEB system.

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Annealing for Tailoring Au/GaN Schottky-Barrier Height

It should be possible to make metal/semiconductor contacts more reproducible. Annealing has been found to be an effective means of tailoring the height of a Schottky barrier between gold and gallium nitride. This finding offers promise for the development of improved metal contacts on GaN semiconductors. Heretofore, the commercialization of GaN semiconductor devices has been impeded by difficulties of fabrication and by nonreproducibility of the Schottky-barrier heights and other properties of the metal/GaN interfaces. Now it appears that annealing may be the key to making GaN devices with smaller unit-tounit variations of contact properties and, in particular, tailorability of Schottky-barrier heights over a wide energy range.

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Ceramics Made From Wood

Properties can be tailored in many different ways. The term “ecoceramics” (a contraction of “environment-conscious ceramics”) denotes a class of ceramics made partly from wood-based products, which can include natural wood, sawdust, cardboard, and/ or paper. In addition to the environmental advantage of renewability of the carbonaceous ingredients, the concept of ecoceramics offers an advantage of tailorability of the properties of the ceramic end products.

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Electroceramic Actuators for Operation at Low Temperatures

Relatively large strokes are produced at temperatures between 30 and 60 K. Electrostrictive ceramic actuators that can function at low temperatures have been developed for controlling the shapes of mirrors in the Next Generation Space Telescope (NGST). On Earth, electrostrictive ceramic actuators may be useful for fine control of the positions of objects in cryogenic laboratory apparatuses and in industrial cryogenic (including superconducting) systems.

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Refrigerant Blends Containing Trifluoroiodomethane

Some of these non-ozone-depleting refrigerants can supplant older ozone-depleting ones. Blends of refrigerant fluids have been developed as improved alternatives to conventional chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) refrigerants, which contribute to depletion of stratosphere ozone. Each blend of this type is a zeotropic or nearly azeotropic mixture of trifluoroiodo-methane (CF3I) with two or three hydro-fluorocarbon (HFC) refrigerant compounds. In addition to having zero ozone-depletion potential, these CF3I-containing refrigerant blends are nonflammable, and have low toxicity, low global-warming potential (GWP), and low total equivalent warming impact (TEWI). [GWP and TEWI are two measures that quantify different aspects of contributions to global warming.]

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Heat-Exchanger Rocket Engine

Engine heat is used to prevaporize liquid oxygen. The proposed rocket engine includes a combustion chamber actively cooled by liquid oxygen: Heat from the combustion chamber vaporizes the flowing liquid oxygen, and the absorption of latent heat of vaporization contributes to cooling of the combustion-chamber wall. The resulting high-vapor-quality (mostly vapor) two-phase flow of oxygen is then injected into the combustion chamber to burn with the fuel. Vaporization of the majority of the oxygen prior to injection renders the engine insensitive to wide variations of inlet conditions.

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