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High Field Superconducting Magnets
Active Response Gravity Offload and Method
Strat-X
Sonar Inspection Robot System
Lightweight Internal Device to Measure Tension in Hollow- Braided Cordage
System, Apparatus, and Method for Pedal Control
Dust Tolerant Connectors
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Accident/Mishap Investigation System

InvestigationOrganizer (IO) is a Webbased collaborative information system that integrates the generic functionality of a database, a document repository, a semantic hypermedia browser, and a rulebased inference system with specialized modeling and visualization functionality to support accident/mishap investigation teams. This accessible, online structure is designed to support investigators by allowing them to make explicit, shared, and meaningful links among evidence, causal models, findings, and recommendations.

Posted in: Briefs, TSP, Software

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Simplified Identification of mRNA or DNA in Whole Cells

This test can be performed using compact, low-power equipment. A recently invented method of detecting a selected messenger ribonucleic acid (mRNA) or deoxyribonucleic acid (DNA) sequence offers two important advantages over prior such methods: it is simpler and can be implemented by means of compact equipment. The simplification and miniaturization achieved by this invention are such that this method is suitable for use outside laboratories, in field settings in which space and power supplies may be limited.

Posted in: Briefs, Medical

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Printed Multi-Turn Loop Antennas for RF Biotelemetry

Compact antennas afford hemispherical coverage at any linear polarization. Printed multi-turn loop antennas have been designed for contactless powering of, and reception of radio signals transmitted by, surgically implantable biotelemetric sensor units operating at frequencies in the vicinity of 300 MHz. In the original intended application of these antennas, the sensor units would be microelectromechanical systems (MEMS)-based devices now being developed for monitoring physiological parameters of humans during space flights. However, these antennas and the sensor units could just as well be used for physiological monitoring on Earth.

Posted in: Briefs, TSP, Medical

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Retaining Rings for Industrial Fastening Applications

Retaining rings are selected based on material, finish, and a variety of application parameters. A discussion of retaining rings inevitably must begin with a debunking of myths; namely, that one style of retaining ring will function better than all other types in all instances. No one retaining ring style is better than another. Rather, the parameters of an application actually determine which retaining ring is best to use, and this can vary from assembly to assembly. Selecting the correct type of retaining ring based on variables such as installation/removal requirements, anticipated thrust load, and end-play take-up can ensure the retaining ring chosen will perform reliably, while significantly reducing fastener costs.

Posted in: Briefs, Mechanical Components

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Glass/BNNT Composite for Sealing Solid Oxide Fuel Cells

Boron nitride nanotubes contribute to strength and fracture toughness. A material consisting of a barium calcium aluminosilicate glass reinforced with 4 weight percent of boron nitride nanotubes (BNNTs) has shown promise for use as a sealant in planar solid oxide fuel cells (SOFCs). The composition of the glass in question in mole percentages is 35BaO + 15CaO + 5Al2O3 + 10B2O3 + 35SiO2. The glass was formulated to have physical and chemical properties suitable for use as a planar- SOFC sealant, but has been found to be deficient in one aspect: it is susceptible to cracking during thermal cycling of the fuel cells. The goal in formulating the glass/BNNT composite material was to (1) retain the physical and chemical advantages that led to the prior selection of the barium calcium aluminosilicate glass as the sealant while (2) increasing strength and fracture toughness so as to reduce the tendency toward cracking.

Posted in: Briefs, TSP, Materials

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Improved Single-Source Precursors for Solar-Cell Absorbers

Deposition properties and final compositions can be tailored. Improved single-source precursor compounds have been invented for use in spray chemical vapor deposition (spray CVD) of chalcopyrite semiconductor absorber layers of thin-film solar photovoltaic cells. The semiconductors in question are denoted by the general formula CuInxGa1–xSySe2–y, where x≤1 and y≤2. These semiconductors have been investigated intensively for use in solar cells because they exhibit longterm stability and a high degree of tolerance of radiation, and their bandgaps correlate well with the maximum photon power density in the solar spectrum. In addition, through selection of the proportions of Ga versus In and S versus Se, the bandgap of CuInxGa1–xSySe2–y can be tailored to a value between 1.0 and 2.4 eV, thus making it possible to fabricate cells containing high and/or graded bandgaps.

Posted in: Briefs, TSP, Materials

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Spray CVD for Making Solar-Cell Absorber Layers

Spray CVD combines the advantages of metalorganic CVD and spray pyrolysis. Spray chemical vapor deposition (spray CVD) processes of a special type have been investigated for use in making CuInS2 absorber layers of thin-film solar photovoltaic cells from either of two subclasses of precursor compounds: [(PBu3) 2Cu(SEt)2In(SEt)2] or [(PPh3)2Cu(SEt)2 In(SEt)2] . CuInS2 is a member of the class of chalcopyrite semiconductors described in the immediately preceding article. [(PBu3)2Cu(SEt)2In(SEt)2] and [(PPh3)2 Cu(SEt)2In(SEt)2] are members of the class of single-source precursors also described in the preceding article.

Posted in: Briefs, TSP, Materials

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