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Rapid-Chill Cryogenic Coaxial Direct- Acting Solenoid Valve

A commercially available cryogenic direct-acting solenoid valve has been modified to incorporate a rapid-chill feature. In the original application for which this feature was devised, there is a requirement to ensure that at all times, the valve outlet flow consists entirely or mostly of liquid; that is, there is a requirement to minimize vaporization of cryogenic liquid flowing through the valve. This translates to a requirement to chill interior valve surfaces in contact with the flowing liquid.

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Electrically Conductive Anodized Aluminum Surfaces

These coatings are highly adherent, transparent, and relatively inexpensive. Anodized aluminum components can be treated to make them sufficiently electrically conductive to suppress discharges of static electricity. The treatment was conceived as a means of preventing static electric discharges on exterior satin-anodized aluminum (SAA) surfaces of spacecraft without adversely affecting the thermal-control/optical properties of the SAA and without need to apply electrically conductive paints, which eventually peel off in the harsh environment of outer space. The treatment can also be used to impart electrical conductivity to anodized housings of computers, medical electronic instruments, telephone-exchange equipment, and other terrestrial electronic equipment vulnerable to electrostatic discharge.

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Composite Solid Electrolyte Containing Li+- Conducting Fibers

Li+-ion conductivities are greater than those achieved before. Improved composite solid polymer electrolytes (CSPEs) are being developed for use in lithium-ion power cells. The matrix components of these composites, like those of some prior CSPEs, are highmolecular- weight dielectric polymers [generally based on polyethylene oxide (PEO)]. The filler components of these composites are continuous, highly-Li+- conductive, inorganic fibers.

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Making Activated Carbon by Wet Pressurized Pyrolysis

Thermomechanical instabilities and associated frequency instabilities are reduced. A wet pressurized pyrolysis (wet carbonization) process has been invented as a means of producing activated carbon from a wide variety of inedible biomass consisting principally of plant wastes. The principal intended use of this activated carbon is room-temperature adsorption of pollutant gases from cooled incinerator exhaust streams.

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Cryogenic Pound Circuits for Cryogenic Sapphire Oscillators

Two modern cryogenic variants of the Pound circuit have been devised to increase the frequency stability of microwave oscillators that include cryogenic sapphire-filled cavity resonators. Invented in the 1940s and named after its inventor (R. V. Pound), the original Pound circuit is a microwave frequency discriminator that provides feedback to stabilize a voltage-controlled microwave oscillator with respect to an associated cavity resonator. Heretofore, Pound circuits used in conjunction with cryogenic resonators have included room-temperature electronic components coupled to the resonators via such inter-connections as coaxial cables. The thermo mechanical instabilities of these inter-connections give rise to frequency instabilities. In a cryogenic Pound circuit of the present improved type, all of the active electronic components, the inter-connections among them, and the inter-connections between them and the resonator reside in the cryogenic environment along with the resonator and, hence, are thermo-mechanically stabilized to a large degree. Hence, further, frequency instabilities are correspondingly reduced.

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Generating a 2D Representation of a Complex Data Structure

A computer program, designed to assist in the development and debugging of other software, generates a two-dimensional (2D) representation of a possibly complex ndimensional (where n is an integer >2) data structure or abstract rank-n object in that other software. The nature of the 2D representation is such that it can be displayed on a non-graphical output device and distributed by non-graphical means. The purpose served by this representation is to assist the user in visualizing and understanding the complex data structure or arbitrarily dimensioned object. This is the only known program that enables a programmer to map an n-dimensional data structure to a flat 2D space. This program does not depend upon the hardware characteristics of a particular output device, and can be executed on a variety of computers from different manufacturers. It can be distributed in source-code or binary-code form. It requires a Lisp compiler. It has no specific memory requirements and depends upon the other software with which it is used and application programs running in it. This software is implemented as a library that is called by, and becomes folded into, the developmental other software.

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Conversion Between Osculating and Mean Orbital Elements

Osculating/Mean Orbital Element Conversion (C version) (OSMEANC) is a C-language computer program that performs precise conversions between osculating and mean classical orbital elements. OSMEANC can be used for precise design of spacecraft missions and maneuvers and precise calculation of planetary orbits. The program accounts for the full complexity of gravitational fields, including aspherical and third-body effects. In comparison with prior software used for the same purposes, OSMEANC offers greater accuracy in conversion: By virtue of inclusion of high-order gravitational and third-body effects, variations in semimajor axes are calculated to meter-level accuracy. OSMEANC is delivered as a callable shared library. It can be built for any platform with a C compiler. The user interface is via a Python-language wrapper script that can be replaced by the user. OSMEANC is mature and is the product of a significant upgrade from a Fortran version that has been in use since 1991.

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