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Briefs: Photonics/Optics
An ultraviolet light source that comprises a tunable diode laser and associated optics provides the optical excitation needed for simultaneous wavelength-modulation-absorption...
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Briefs: Manufacturing & Prototyping
Latently reactive end caps have been investigated as improved means to increase the thermo-oxidative stability of polyimides of the polymerization of monomeric reactants (PMR) type,...
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Briefs: Materials
An additional class of end-cap compounds that increase the thermo-oxidative stability of polyimides of the polymerization of monomeric reactants (PMR) type has been invented. The prior...
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Briefs: Motion Control
Miniature electroactive-polymer rakes (MEARs) are undergoing development for eventual use as simple, lightweight, inexpensive low-power-consumption devices that would remove soil, dust, and/or other loose...
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Briefs: Mechanical & Fluid Systems
A proposal has been made to develop bimorph actuators and force sensors based on carbon nanotubes. The proposed devices could make it possible to generate, sense, and control displacements and...
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Briefs: Materials
Experiments have shown that ultrasound could be an effective means of enhancing the removal of chlorinated hydrocarbon contaminants from groundwater by the zero-valent-metal treatment...
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Briefs: Materials
Thermal Insulation Would Use CO2 in the Martian Environment
A report describes the development of a lightweight thermal insulation system for Martian surface applications. The ambient Martian atmosphere, which is predominantly carbon dioxide at a pressure of 10 torr, is used as the insulation medium with a modest multiple radiation shield...
Briefs: Medical
Electrokinetically enhanced bioremediation (EEB) is a method of engineered bioremediation of soil contaminated by such organic compounds as solvents and petroleum products. As depicted...
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Briefs: Physical Sciences
Model of Pyrolysis of Biomass in a Fluidized-Bed Reactor
A mathematical model has been formulated to describe the pyrolysis of biomass in a bubbling fluidized-bed reactor. The reactor is a vertical cylinder that contains a mixture of biomass particles and sand. Superheated steam enters the reactor through holes in the bottom and flows out freely at...
Briefs: Physical Sciences
A portable apparatus that operates at atmospheric pressure generates a beam of monatomic oxygen. The apparatus is designed to be used in a dry, noncontact process for removing organic...
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Briefs: Mechanical & Fluid Systems
Molten-Carbonate Oxidation of Solid Waste
The molten-carbonate oxidation (MCO) process shows promise as a means of safe disposal and/or recycling of solid waste. The MCO process is being developed for use in regenerative life-support systems in outer space, but may also prove useful in managing institutional, industrial, and/or municipal solid...
Briefs: Materials
Improved Polymeric Composite Materials for Dental Fillings
Composite materials that include combinations of metal oxide and silica nanoparticles in polymeric matrices have been invented for primary use as dental fillings, dental and bone adhesives, and the like. There have been previous efforts to develop polymeric replacements for the amalgam...
Briefs: Materials
Metal-supported catalyst beds with improved thermal and flow characteristics for promoting endothermic chemical reactions are undergoing development. In the proposed original application,...
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Briefs: Materials
In catalytic flow-through chemical reactors being explored for space vehicle applications, the catalysts would be supported on the surfaces of wires, instead of on particles, as are typically used in...
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Briefs: Manufacturing & Prototyping
A process for making precise, high-quality curved or flat mirror surfaces on bare aluminum substrates has been devised. The process consists of (1) diamond turning to establish the...
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Briefs: Electronics & Computers
Signal Processor for Doppler Measurements in Icing Research
An advanced signal processor has been developed to enable high-resolution measurement of the frequency and phase shifts of noisy laser Doppler velocimeter (LDV) and phase Doppler particle analyzer (PDPA) signals. The purpose of the measurements is to exploit the phase Doppler principle to...
Briefs: Mechanical & Fluid Systems
A normally closed, piezoelectrically actuated microvalve is being developed as a prototype of valves in microfluidic systems and other microelectromechanical systems (MEMS) intended for...
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Briefs: Test & Measurement
Real-Time Optoelectronic Particle-Fallout Monitors
Optoelectronic instruments for real-time, in situ monitoring of particle fallout are undergoing development. Settings in which these instruments could prove useful include clean rooms for assembly of optical and electronic equipment, food-packaging facilities, and other industrial facilities in...
Briefs: Physical Sciences
A hand-held instrument that contains two silicon-based charge-coupled-device (CCD) video cameras (see figure) has been developed for imaging hydrogen fires. This or a similar instrument is needed...
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Briefs: Electronics & Computers
"PR-2" denotes a proposed spaceborne radar system for measuring three-dimensional rainfall profiles and rainfall velocities. The PR-2 system would incorporate a number of...
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Briefs: Mechanical & Fluid Systems
The EXOS computer program numerically simulates impacts of orbital debris on spacecraft. EXOS can be used to simulate meteoroid- and orbital-debris-impact damage to commercial...
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Briefs: Materials
A method of fabricating composites of pretreated silicon carbide fibers in silicon carbide matrices provides for the formation of improved boron nitride fiber/matrix interfacial layers. As...
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Briefs: Electronics & Computers
A developmental apparatus and process for the fabrication of photonic devices utilize intense, focused laser light projected and/or diffracted in controlled patterns. The apparatus and process can be...
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Briefs: Electronics & Computers
The Atmospheric Electron X-ray Spectrometer (AEXS) is being developed for performing rapid, nondestructive in situ analyses of the elemental composition of surfaces. The capability of the AEXS to operate...
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Briefs: Physical Sciences
Designing Purging Flows of Clean, Dry Gases
A method of designing purging flows of clean, dry gases to maintain acceptably low levels of contamination in enclosed volumes has been developed. The method is applicable to diverse enclosures that must be kept clean, including housings of precise optical instruments, clinical facilities, facilities for...
Briefs: Physical Sciences
Simulations of a Transitional Droplet-Laden Mixing Layer
A report describes direct numerical simulations of a droplet-laden mixing layer (e.g., evaporating droplets of a hydrocarbon fuel in air) undergoing a transition to mixing turbulence. The governing equations are those of Lagrangian transport of discrete droplets through a flowing gas, which...
Briefs: Materials
Enhanced Shield Against Meteoroids and Orbital Debris
NASA scientists, who are very concerned with the increasing hazard of impacts of orbital debris impact on spacecraft, have designed the "stuffed Whipple" shield — a lightweight, relatively inexpensive alternative to simple aluminum meteoroid/orbital-debris (M/OD) shield. The stuffed Whipple...
Briefs: Test & Measurement
An optoelectronic instrument, known as a plant fluorescence sensor, is being developed for use as a working tool in agricultural settings. This instrument is a remote, passive monitor...
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Briefs: Materials
Aerogels With Gradients of Density
Aerogels with gradients in density have been produced in experiments, as part of an effort to develop materials that will be used in outer space to capture particles traveling at high speeds for the STARDUST mission.

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