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Physical Sciences

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Briefs: Physical Sciences

Two condensers designed for use in dissipating heat carried by working fluids feature two-phase, self-adjusting configurations such that their working lengths automatically vary to suit their input power levels...

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Briefs: Physical Sciences
Sensor for Monitoring Nanodevice-Fabrication Plasmas

The term "plasma process diagnostics" (PPD) refers to a spectroscopic technique and sensing hardware that have been proposed for monitoring plasma processes used to fabricate electronic devices that feature sizes as small as several nanometers. Nanometer dimensions are characteristic of the...

Briefs: Physical Sciences
Slotting Fins of Heat Exchangers To Provide Thermal Breaks

Heat exchangers that include slotted fins (in contradistinction to continuous fins) have been invented. The slotting of the fins provides thermal breaks that reduce thermal conduction along flow paths (longitudinal thermal conduction), which reduces heat-transfer efficiency. By...

Briefs: Physical Sciences
Methane Clathrate Hydrate Prospecting

A method of prospecting for methane has been devised. The impetus for this method lies in the abundance of CH4 and the growing shortages of other fuels. The method is intended especially to enable identification of subpermafrost locations where significant amounts of methane are trapped in the form of...

Briefs: Physical Sciences

Scanning microscopes that would be based on microchannel filters and advanced electronic image sensors and that utilize x-ray illumination have been proposed. Because the finest resolution...

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Briefs: Physical Sciences

A method of processing digital image data to detect edges includes the use of fuzzy reasoning. The method is completely adaptive and does not require any advance knowledge of an image.

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Briefs: Physical Sciences
Foam Sensor Structures Would Be Self-Deployable and Survive Hard Landings

A document proposes systems of sensors encased in cold hibernated elastic memory (CHEM) structures for exploring remote planets. The CHEM concept was described in two prior NASA Tech Briefs articles, including “Cold Hibernated Elastic Memory (CHEM) Expandable...

Briefs: Physical Sciences
Real-Gas Effects on Binary Mixing Layers

This paper presents a computational study of real-gas effects on the mean flow and temporal stability of heptane/ nitrogen and oxygen/ hydrogen mixing layers at supercritical pressures. These layers consist of two counter- flowing free streams of different composition, temperature, and density. As in...

Briefs: Physical Sciences
Wedge Heat-Flux Indicators for Flash Thermography

Wedge indicators have been proposed for measuring thermal radiation that impinges on specimens illuminated by flash lamps for thermographic inspection. Heat fluxes measured by use of these indicators would be used, along with known thermal, radiative, and geometric properties of the specimens, to...

Briefs: Physical Sciences
Earth-Space Link Attenuation Estimation via Ground Radar Kdp

A method of predicting attenuation on microwave Earth/ spacecraft comm- unication links, over wide areas and under various atmospheric conditions, has been developed. In the area around the ground station locations, a nearly horizontally aimed polarimetric S-band ground radar measures...

Briefs: Physical Sciences
Update on Area Production in Mixing of Supercritical Fluids

The paper “Turbulence and Area Production in Binary-Species, Super- critical Transitional Mixing Layers” presents a more recent account of the research sum- marized at an earlier stage in “Area Production in Super- critical, Transitional Mixing Layers” (NPO-30425), NASA Tech...

Briefs: Physical Sciences
Dyakonov-Perel Effect on Spin Dephasing in n-Type GaAs

A paper presents a study of the contribution of the Dyakonov-Perel (DP) effect to spin dephasing in electron-donor-doped bulk GaAs in the presence of an applied steady, moderate magnetic field perpendicular to the growth axis of the GaAs crystal. (The DP effect is an electron-wave-...

Briefs: Physical Sciences

Conventional commercial spectrometers or spectrophotometers are usually able to measure optical spectrum from a specified surface area at one...

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Briefs: Physical Sciences
Reconditioned Test Equipment as a Key Driver in Reducing Life Cycle Support Costs

Previously owned test and measurement equipment has been purchased for over 50 years by the United States military, agencies of the Federal gov- ernment, and prime contractors that support these organizations. Yet, despite the significant amount of previously owned...

Briefs: Physical Sciences

The figure shows a fixture for measuring the tensile strength of the bond between an aluminum substrate and a thermally insulating polymeric foam. The specimen is meant to be...

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Briefs: Physical Sciences

Langley Research Center has developed electrical- impedance- based icethickness gauges and is seeking partners and collaborators to commercialize them. When used as parts of active monitoring...

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Briefs: Physical Sciences

Slat heater boxes have been invented for controlling the sink temperatures of objects under test in a thermal vacuum chamber, the walls of which are cooled to the temperature of liquid nitrogen. A...

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Briefs: Physical Sciences

An apparatus and method have been developed for measuring the rates of leakage of heat into pipes carrying liquids, the purpose of the measurements being to quantify the thermal performance of...

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Briefs: Physical Sciences
Scaling of Two-Phase Flows to Partial-Earth Gravity

A report presents a method of scaling, to partial-Earth gravity, of parameters that describe pressure drops and other characteristics of two-phase (liquid/ vapor) flows. The development of the method was prompted by the need for a means of designing two-phase flow systems to operate on the Moon...

Briefs: Physical Sciences
Swarms of Micron-Sized Sensors

A paper presents the concept of swarms of micron-sized and smaller carriers of sensing equipment, denoted generally as controllable granular matter, to be used in exploring remote planets and interplanetary space. The design and manufacture of controllable granular matter would exploit advances in...

Briefs: Physical Sciences

A three-dimensional (3D) Venturi sensor is being developed as a compact, rugged means of measuring wind vectors having magnitudes of as much as 300 mph (134 m/s). This sensor also...

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Briefs: Physical Sciences

A device that generates an alarm when the partial pressure of oxygen decreases to less than a preset level has been developed to help prevent hypoxia in a pilot or other crewmember of a...

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Briefs: Physical Sciences

Figure 1 depicts some aspects of an apparatus and method for automated serial sectioning of a specimen of a solder, aluminum, or other relatively soft opaque material. The apparatus includes...

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Briefs: Physical Sciences
Tilt-Sensitivity Analysis for Space Telescopes

A report discusses a computational- simulation study of phase- front propagation in the Laser Interferometer Space Antenna (LISA), in which space telescopes would transmit and receive metrological laser beams along 5-Gm interferometer arms. The main objective of the study was to determine the...

Briefs: Physical Sciences
Study of Dislocation-Ordered InₓGa₁₋ₓAs/GaAs Quantum Dots

A report describes an experimental study of dislocation-induced spatial ordering of quantum dots (QDs) comprising nanometer-sized InxGa1–xAs islands surrounded by GaAs. Metastable hetero-epitaxial structures were grown by molecular-beam epitaxy of...

Briefs: Physical Sciences

Electrochemical systems that are especially well suited for the small-scale generation of ozone and ozonated water for local use have been invented. These systems can operate with...

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Briefs: Physical Sciences

The imposition of a magnetic field has been proposed as a means of reducing the electron backstreaming problem in ion thrusters.

Electron backstreaming refers to the...

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Briefs: Physical Sciences

A proposed inchworm actuator, to be designed and fabricated according to the principles of microelectromechanical systems (MEMS), would effect linear motion characterized by steps as...

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Briefs: Physical Sciences

A method of predicting and preventing incipient flameout in a combustor has been proposed. The method should be applicable to a variety of liquid- and gas-fueled combustors in...

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