Briefs: Physical Sciences
A computer-controlled instrumentation system has been developed for use in measuring concentrations of various atomic species in the exhaust gases of a space-shuttle main engine on a...
Briefs: Electronics & Computers
A dynamic random-access memory (DRAM) circuit that tolerates single-event upsets (SEUs) has been developed. A single-event upset is a bit flip caused by ionizing radiation. In a DRAM, the state of each bit (0 or 1) is stored as charge on a buried capacitor. The impingement of an energetic charged particle...
Briefs: Physical Sciences
Electromagnetic particle-in-cell (EMPIC) codes provide a capability for numerically simulating the motions of electrically charged particles in electromagnetic fields, and hence have become standard software tools in plasma physics research. Most existing EMPIC codes are based on the use of...
Briefs: Materials
Nonevaporable getters have been proposed for use in maintaining vacuum inside hermetically sealed microelectromechanical systems (MEMS) that rely on vacuum for proper operation. A vibratory microgyroscope is an example of such a MEMS. The proposed getters could also be used in such vacuum...
Briefs: Physical Sciences
The Generalized Fluid System Simulation Program (GFSSP) version 2.01 is a general-purpose computer program for analyzing steady-state and time-dependent flowrates, pressures, temperatures, and concentrations in a complex flow network. The program is capable of modeling phase changes,...
Briefs: Electronics & Computers
Improved thermoelectric converter units (TCUs) and radioisotope thermoelectric generators (RTGs) that contain them have been undergoing development for use as small, lightweight...
Briefs: Electronics & Computers
The pixelated array detector (PAD) is a planar array of complementary metal oxide/semiconductor (CMOS) charge-collecting electrodes and readout circuitry for measuring the electric charges...
Briefs: Photonics/Optics
An optical sensor for measuring the partial pressure of dissolved oxygen in water is based on the effect of oxygen quenching on the fluorescence lifetime of an optically excited ruthenium complex immobilized in a recently developed polymer. In the operation of this sensor, the fluorescence...
Briefs: Photonics/Optics
The figure shows a first-phase prototype of a miniature, rugged long-wavelength infrared (LWIR) spectrometer that incorporates recent advances in the design and fabrication of microelectronic and...
Briefs: Physical Sciences
A mathematical model constructed within a theoretical framework applicable to direct numerical simulation (DNS) predicts the behavior of evaporating liquid drops entrained in a turbulent...
Briefs: Materials
Rechargeable lithium-ion electrochemical cells that contain anodes made from a mixture of graphite and carbon black have been found to perform better than do similar cells that contain anodes made...
Briefs: Materials
Improved polymer electrolyte membranes for direct methanol fuel cells can be made by any of a variety of processes in which cross-linked polystyrene sulfonic acid (PSSA) is...
Briefs: Physical Sciences
A method of computing the concentrations of chemical species in chemically reacting flows includes, among other things, utilization of a prior chemical-kinetic method based on a concept...
Briefs: Electronics & Computers
Studies of physical and chemical effects in the hydride-forming electrodes of rechargeable nickel/metal hydride electrochemical cells have yielded results that now guide...
Briefs: Robotics, Automation & Control
Early experiments in a continuing research program have demonstrated that thermal batteries made from powdered solid electrode and electrolyte materials can be improved by use of smaller...
Briefs: Photonics/Optics
A report describes experiments in which nonintrusive optical diagnostic techniques were applied to high-pressure fuel sprays in simulated advanced turbine-engine combustor environments. The experiments involved three different fuel injectors in two unique optically accessible combustors: a...
Briefs: Test & Measurement
A segmented-image emission velocimeter (SIEVE) is an optical instrument for measuring the velocity of a luminous turbulent flow. More specifically, it measures a component of flow...
Briefs: Physical Sciences
Improved silicon carbide-based Schottky diodes are undergoing development for use in detecting hydrocarbon (CxHy) and nitrogen oxide (NOx) gases at high temperatures. In comparison...
Briefs: Photonics/Optics
An optical technique for measuring the concentration of soot in air is based on the cavity-ring-down (CRD) principle, which is so named because it involves observation of the decay...
Briefs: Physical Sciences
A unique dual-flow, cold-jet facility has been developed and operated by California Polytechnic State University (Cal Poly) at San Luis Obispo for NASA Dryden Flight Research Center. The...
Briefs: Robotics, Automation & Control
Miniature, lightweight, low-power, low-vibration Joule-Thomson Rankine-Cycle refrigerators have been proposed for cooling portable scientific instruments. These refrigerators would be made...
Briefs: Robotics, Automation & Control
A report describes a small, lightweight sorption compressor that is now undergoing development for use in collecting CO2 from the atmosphere on Mars. This compressor would be part of a system that would use the CO2 to generate oxygen and a carbon-based fuel for a spacecraft to return...
Briefs: Materials
A new process and equipment have been developed for reducing the emissions of hazardous nitrogen oxides (NOx), and eliminating a hazardous waste stream. In this process, a waste gas...
Briefs: Information Technology
A worksheet has been constructed within the Microsoft Excel software system for converting raw particle-fallout data into percentages of obscuration; that is, percentages of areas obscured by particles on surfaces. These obscuration levels are needed for assessing contamination levels in...
Briefs: Energy
The recent summit meeting held in Kyoto, Japan, has brought world-wide attention to the issue of global climate change. For the past 5 years, the Department of Energy's Atmospheric Radiation...
Briefs: Physical Sciences
Simple optical devices called "scattering reticles" have been invented for calibrating Phase Doppler Particle Analyzers (PDPAs), which are optical instruments that analyze scattered light to determine the sizes and velocities of droplets. A scattering reticle comprises a polymeric...
Briefs: Materials
Current production thermal-barrier coatings (TBCs) have been shown to be capable of reducing the average temperatures of metallic components by 50 to 80 °C and hot-spot temperature by up...
Briefs: Physical Sciences
Quasi-thermostatic gas-gap thermal switches have been proposed. These switches would operate automatically, would contain no moving parts, would not require power supplies or controls, would not...
Briefs: Electronics & Computers
Plasma windows can separate vacuum and atmosphere, or regions of high and low vacuums, in a way which facilitates transmission of various particle beams and/or radiation from low- to high-pressure regions. In a prototype device, a stabilized plasma arc...