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Simultaneous Conoscopic Holography and Raman Spectroscopy

Both the topography and the chemistry of surfaces would be mapped.

Posted in: Test & Measurement, Briefs, TSP

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Instrumentation for Sensitive Gas Measurements

Measurements are based on cavity-enhanced absorption.

Posted in: Test & Measurement, Briefs

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Apparatus for Testing Flat Specimens of Thermal Insulation

An improved design affords flexibility for testing under diverse conditions.

Posted in: Test & Measurement, Briefs, TSP

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Quadrupole Ion Mass Spectrometer for Masses of 2 to 50 Da

H2, He, O2, and Ar can be quantitated at low concentrations in N2

Posted in: Test & Measurement, Briefs, TSP

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Miniature Laser Doppler Velocimeter for Measuring Wall Shear

Interference fringes are configured for sensitivity to a velocity gradient.

Posted in: Test & Measurement, Briefs, TSP

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Sol-Gel Process for Making Pt-Ru Fuel-Cell Catalysts

Relative to another process, this one takes less time and yields better results. A sol-gel process has been developed as a superior alternative to a prior process for making platinum-ruthenium alloy catalysts for electro-oxidation of methanol in fuel cells. The starting materials in the prior process are chloride salts of platinum and ruthenium. The process involves multiple steps, is time-consuming, and yields a Pt-Ru product that has relatively low specific surface area and contains some chloride residue. Low specific surface area translates to incomplete utilization of the catalytic activity that might otherwise be available, while chloride residue further reduces catalytic activity (“poisons” the catalyst). In contrast, the sol-gel process involves fewer steps and less time, does not leave chloride residue, and yields a product of greater specific area and, hence, greater catalytic activity.

Posted in: Materials, Briefs, TSP

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Corrosion-Prevention Capabilities of a Water-Borne, Silicone- Based, Primerless Coating

Some formulations are better for steel, some for aluminum. Comparative tests have been performed to evaluate the corrosion-prevention capabilities of an experimental paint of the type described in “Water-Borne, Silicone-Based, Primerless Paints,” NASA Tech Briefs, Vol. 26, No. 11 (November 2002), page 30. To recapitulate: these paints contain relatively small amounts of volatile organic solvents and were developed as substitutes for traditional anticorrosion paints that contain large amounts of such solvents. An additional desirable feature of these paints is that they can be applied without need for prior application of primers to ensure adhesion.

Posted in: Materials, Briefs

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