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Briefs: Physical Sciences

A heat exchanger made largely from pieces of single-crystal silicon has been designed for use as a recuperator in a reverse-Brayton-cycle cryocooler. Its design is optimized for transferring...

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Briefs: Physical Sciences

A computational method for designing all-dielectric grating electromagnetic filters involves a combination of (1) numerical simulation of filter performance via integral-equation...

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Briefs: Physical Sciences

The figure shows the basic optical configuration of an improved all-reflecting imaging spectrometer. This spectrometer would differ from older spectrometers in several respects, one...

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Briefs: Physical Sciences

A method that includes the use of modified equations of state has been developed to enable noniterative, efficient computation of the thermodynamic behaviors of gases and liquids at...

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Briefs: Physical Sciences

The figure illustrates an apparatus for measuring heat-transfer and pressure-drop characteristics of porous plug specimens in oscillating flows. The apparatus is built around an...

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Briefs: Physical Sciences

A highly sensitive micromachined accelerometer that is intended to be exposed to very small accelerations during operation incorporates features for protection against much larger...

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Briefs: Physical Sciences
Evaluation of Droplet-Evaporation Models for Gas/Liquid Flow

A report presents an evaluation of eight mathematical models of the evaporation of liquid droplets — models that are used in the numerical simulation of a variety of gas/liquid flows, including cooling sprays, burning liquid-fuel sprays, fire-suppression sprays, and...

Briefs: Physical Sciences
Production of Tar in Pyrolysis of Large Biomass Particles

A paper presents a study of the production of tar in the pyrolysis of spherical biomass particles, with computational simulations performed by using the macroparticle portion of the model described in "Generalized Mathematical Model of Pyrolysis of Plant Biomass" (NPO-20068) elsewhere in...

Briefs: Medical

A compact fiber-optic probe has been found to be useful for noncontact diagnosis of interior parts of eyes. The probe was originally developed for performing...

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Briefs: Physical Sciences

A generalized mathematical model has been devised for use in analyzing the pyrolysis of arbitrarily specified (but typical) biomass feedstocks at atmospheric pressure. The model...

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Briefs: Physical Sciences

The Automated Window Inspection Device (AWID) is a prototype apparatus for computer-controlled, noncontact inspection of windows, with reproducible positioning and electronic recording of data on the...

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Briefs: Physical Sciences

A mathematical model of a special class of solid/fluid chemical reactions has been developed for use in analyzing the pyrolysis of particles of cellulose, wood, and similar biomass...

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Briefs: Physical Sciences

A mathematical model has been developed for use in assessing the performances of direct-contact pyrolysis reactors used to convert particles of raw biomass materials (usually small...

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Briefs: Physical Sciences

A method of correcting absolute-air-pressure measurements for small differences in the elevations of pressure taps and pressure transducers has been devised. The variation in air...

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Briefs: Physical Sciences

Significant effort and resources are being expended to develop ceramic-matrix composite (CMC), metal-matrix composite (MMC), and polymer-matrix composite (PMC) materials for...

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Briefs: Physical Sciences

A device for measuring the distribution of masses in an atmosphere or plasma exploits the electrostatic deflection of ions in a rotating magnetic field. A magnetic field is not required. The device...

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Briefs: Physical Sciences
Adjacent-Pair Imaging Shearography Using Bacteriorhodopsin

In a developmental technique of real-time adjacent-pair imaging shearography, a thin film of bacteriorhodopsin is used to record shearograms in argon-laser light for immediate readout in helium/neon-laser light. Unlike conventional silver-halide-based photographic film, bacteriorhodopsin...

Briefs: Physical Sciences

The figure illustrates a solar thermal energy system for boiling water or another liquid. The system can be used for a variety of purposes that can include drying aqueous hazardous...

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Briefs: Medical

A method of measuring the concentration of a selected organic compound (analyte) in a sample of water involves (1) producing hydrogen peroxide as a byproduct of enzyme-catalyzed...

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Briefs: Physical Sciences
Potential Commercial Applications From Microgravity Combustion Research

The paper entitled "Potential Commercial Applications From Combustion and Fire Research in Space" reviews the status of potential commercial applications derived from research on combustion in microgravity environments encountered in orbiting spacecraft. Such research...

Briefs: Physical Sciences

Kinetic rate data are needed to design all chemical processes. Specifically, they are needed to determine such things as ignition delay times, combustion times, and explosion...

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Briefs: Materials

Experiments have shown that nonreactive ion-beam sputtering can be used to deposit a transparent film of aluminum oxide on a polycarbonate, silicon, or fused-silica substrate....

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Briefs: Test & Measurement
Proximity Measurement of Pressure and Temperature

Inexpensive, high-performance, optically coupled temperature and strain gauges based on a combination of advanced optoelectronic and microelectromechanical concepts have been proposed. The sensors would contain vibrating beams with submillimeter dimensions, made primarily of silicon by...

Briefs: Physical Sciences
A Multicolor Imaging Pyrometer

Physical Sciences Inc. (PSI) designed, constructed, and delivered a prototype passive imaging pyrometer capable of accurately measuring and controlling the temperature distribution across a specified surface. The device was originally designed, under a NASA SBIR contract (solicitation year 1985) monitored by Jet...

Briefs: Physical Sciences

An integrated thin-film device has been designed to constitute the sensory element of a miniature instrument for measuring the concentration of an atomic or molecular species that exhibits...

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