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Lightweight Internal Device to Measure Tension in Hollow- Braided Cordage
System, Apparatus, and Method for Pedal Control
Dust Tolerant Connectors
Foldable and Deployable Power Collection System
Iodine-Compatible Hall Effect Thruster
Development of a Novel Electrospinning System with Automated Positioning and Control Software
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JavaGenes Molecular Evolution

JavaGenes is a general-purpose, evolutionary software system written in Java. It implements several versions of a genetic algorithm, simulated annealing, stochastic hill climbing, and other search techniques. This software has been used to evolve molecules, atomic force field parameters, digital circuits, Earth Observing Satellite schedules, and antennas. This version differs from version 0.7.28 in that it includes the molecule evolution code and other improvements. Except for the antenna code, JaveGenes is available for NASA Open Source distribution.

Posted in: Briefs, Software

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Accounting for Uncertainties in Strengths of SiC MEMS Parts

Fracture strength of a part can be predicted as one statistical distribution. A methodology has been devised for accounting for uncertainties in the strengths of silicon carbide structural components of microelectromechanical systems (MEMS). The methodology enables prediction of the probabilistic strengths of complexly shaped MEMS parts using data from tests of simple specimens. This methodology is intended to serve as a part of a rational basis for designing SiC MEMS, supplementing methodologies that have been borrowed from the art of designing macroscopic brittle material structures.

Posted in: Briefs, TSP, Materials

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Lithium Dinitramide as an Additive in Lithium Power Cells

This inorganic additive appears to act as a superior SEI promoter. Lithium dinitramide, LiN(NO2)2 has shown promise as an additive to nonaqueous electrolytes in rechargeable and non-rechargeable lithium-ion-based electrochemical power cells. Such non-aqueous electrolytes consist of lithium salts dissolved in mixtures of organic ethers, esters, carbonates, or acetals. The benefits of adding lithium dinitramide (which is also a lithium salt) include lower irreversible loss of capacity on the first charge/discharge cycle, higher cycle life, lower self-discharge, greater flexibility in selection of electrolyte solvents, and greater charge capacity.

Posted in: Briefs, Materials

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Ion-Conducting Organic/Inorganic Polymers

Properties can be tailored through a choice of starting alkoxysilane and diamine ingredients. Ion-conducting polymers that are hybrids of organic and inorganic moieties and that are suitable for forming into solidelectrolyte membranes have been invented in an effort to improve upon the polymeric materials that have been used previously for such membranes. Examples of the prior materials include perfluorosulfonic acid-based formulations, polybenzimidazoles, sulfonated polyetherketone, sulfonated naphthalenic polyimides, and polyethylene oxide (PEO)-based formulations. Relative to the prior materials, the polymers of the present invention offer greater dimensional stability, greater ease of formation into mechanically resilient films, and acceptably high ionic conductivities over wider temperature ranges. Devices in which films made of these ion-conducting organic/ inorganic polymers could be used include fuel cells, lithium batteries, chemical sensors, electrochemical capacitors, electrochromic windows and display devices, and analog memory devices.

Posted in: Briefs, TSP, Materials

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MoO3 Cathodes for High-Temperature Lithium Thin-Film Cells

Cycle lives of these cathodes exceed those of LiCoO2 and LiMn2O4 cathodes. MoO3 has shown promise as a cathode material that can extend the upper limit of operating temperature of rechargeable lithium thin-film electrochemical cells. Cells of this type are undergoing development for use as energy sources in cellular telephones, wireless medical sensors, and other, similarly sized portable electronic products. The LiCoO2 and LiMn2O4 cathodes heretofore used in these cells exhibit outstanding cycle lives (of the order of hundreds of thousands of cycles) at room temperature, but operation at higher temperatures reduces their cycle lives substantially: for example, at a temperature of 150 °C, cells containing LiCoO2 cathodes lose half their capacities in 100 charge/discharge cycles.

Posted in: Briefs, TSP, Materials

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Dr. Karen Jackson, Aerospace Engineer, Landing and Impact Research (LandIR) Facility

NASA Langley Research Center, Hampton, VA Dr. Karen JacksonIn a crash, keeping the occupants alive and uninjured is paramount. In order to study the dynamics of an impact, military and general aviation aircraft, like cars, must be tested for their ability to keep their riders safe. A part of Structural Dynamics Branch in the Research and Technology Directorate at NASA Langley, the Landing and Impact Research Facility (LandIR) tests aircraft by crashing them. Dr. Karen Jackson is part of the research team.

Posted in: Who's Who

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Desktop 3D Scanner

NextEngine, Santa Monica, CA, offers the Desktop 3D Scanner, a full-color multi-laser scanner that scans complex shapes for CAD and 3D design applications on the desktop. About the size of a cereal box, the scanner connects directly to a PC via USB 2.0. It operates with proprietary MultiStripe Laser Triangulation (MLT) technology that features twin arrays of four Class 1M 10-mW solid-state lasers with custom optics at a 650-nm wavelength. The scanner also features twin 3-megapixel CMOS RGB image sensors, optically synchronous RGB color texture capture, and built-in spatially diverse white-light texture illuminators. Full-color photo data is captured for each surface point, and there is no preset limit for the size of objects to be scanned. Objects larger than 5.1 x 3.8" in macro mode and 13.5 x 10.1" in wide mode can be composite-captured with supplied ScanStudio(tm) software. The unit has throughput of 50,000 processed points per second, and comes with an AutoPositioner(tm) to capture multiple surfaces of objects, and a PartGripper(tm) to secure objects during scanning. For Free Info Visit http://info.hotims.com/10966-120

Posted in: Products

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