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Physical Sciences

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Briefs: Physical Sciences
System for Delivering Gas Samples to Multiple Instruments

A system that samples gases at multiple remote locations and delivers the gases to two or possibly more gas-monitoring instruments (e.g., mass spectrometers) has been developed. The system includes a transport (suction) pump that draws the gases from the sampling locations, through...

Briefs: Physical Sciences

The term "optical nose" refers to a fiber-optic chemical sensor of a type that has been proposed to enable distributed measurement of the concentrations of...

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Briefs: Physical Sciences

A recently developed type of fiber-optic temperature sensor utilizes narrow-band near-infrared radiation emitted by rare-earth ions. These sensors are suitable for use in harsh environments at...

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Briefs: Physical Sciences
Capacitive Sensor for Measuring Level of Liquid Nitrogen

The feasibility of a capacitive sensor for measuring the level of liquid nitrogen in a container has been demonstrated. The basic sensor design could also readily be adapted to measurement of the levels of cryogenic liquids other than nitrogen.

Briefs: Physical Sciences

Microelectromechanical sensors based on magnetoresistance have been proposed. Like other microelectromechanical sensors, these would be used to measure physical quantities that can be...

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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...

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...

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Briefs: Information Technology
General-Purpose Wavelet Program

"S+Wavelets" is the name of a computer program that implements a suite of mathematical "tools" for wavelet analysis of signals (including two-dimensional signals that represent images.) Wavelets, being localized in both time and frequency (or space and wave number), serve as means for transforming and extracting...

Briefs: Physical Sciences

Experiments have demonstrated the feasibility of using flame-heated refractory dielectric solid bodies as wavelength-selective sources of light for special applications; in...

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Briefs: Physical Sciences

Simple fiber-optic couplers have been devised for use in coupling light into and out of the "whispering-gallery" electromagnetic modes of transparent microspheres. The need for this type...

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Briefs: Physical Sciences

A diffraction grating consisting of a periodic gradient in the index of refraction of a thin surface layer has been shown to be effective as a means of far-field coupling of...

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Briefs: Physical Sciences

Laser thermogravimetric analysis (laser TGA) is a technique that yields time-resolved data on the thermal decomposition of a specimen of a solid material exposed to a heat flux comparable to the...

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Briefs: Physical Sciences
Ultralight Balloon Systems for Exploring Uranus and Neptune

A report proposes ultralight balloon systems to carry a 10-kg payload, including scientific instruments for exploring the atmospheres of Uranus and Neptune. The system masses to be transported to those planets would be kept low by not transporting balloon-inflating gases. Each...

Briefs: Physical Sciences

A proposed method of compressing image data would exploit the well-known capability of a converging lens to generate the Fourier transform of an image by purely optical means, in much...

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Briefs: Physical Sciences

In an alternative to the optical image-compression method of the preceding article, the Fourier transform of the input image would be formed on the output plane by white-light holography,...

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Briefs: Physical Sciences

Biomorphic gliders are small robotic microflyers proposed for use in scientific exploration of planetary atmospheres and terrains that capture some key features of insect and bird flight. Biomorphic gliders as biomorphic...

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Briefs: Physical Sciences

A process and a laboratory setup to implement the process (see figure) have been devised to enable the acquisition of time-resolved data on the thermal decomposition of a specimen of...

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Briefs: Physical Sciences
Updated Multidisciplinary Optical-System-Analysis Software

Version 5.0 of the Integrated Modeling of Optical Systems (IMOS) software has been released. A previous version was described in "Software for Multidisciplinary Analysis of Optical Systems" (NPO-20536), NASA Tech Briefs, Vol. 24, No. 11 (November 2000), page 36. In both versions, IMOS...

Briefs: Physical Sciences

A field-reversed configuration (FRC) has been proposed for a magnetic mirror — a solenoidal electromagnet configured and operated in such a way as to effect at least partial...

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Briefs: Manned Systems

The NASA Dryden DC-8 Airborne Science Laboratory (see Figure 1) performs research around the globe, recently in support of the SAGE III Ozone Loss and Validation Experiment (SOLVE). This...

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Briefs: Physical Sciences
Apparatus Would Extract Water From the Martian Atmosphere

A report proposes an apparatus that would extract water from the atmosphere of Mars and would consume little energy in doing so. The apparatus would include a set of copper plates surrounded by a thermal shield with slots through which atmospheric gas could circulate. At night, the slots...

Briefs: Physical Sciences
Review of Research on Supercritical vs. Subcritical Fluids

A paper reviews theoretical and experimental research on the behaviors of supercritical fluids and, for comparison, subcritical fluids. Experiments with drops, isolated or in groups, streams, shear layers, mixing layers, jets, and sprays are tabulated and discussed as a precursor...

Briefs: Physical Sciences
Study of Fusion-Driven Plasma Thruster With Magnetic Nozzle

A report presents a computational study of a proposed plasma thruster for a spacecraft. The behavior of the plasma was computationally simulated by use of a mathematical model of magnetohydrodynamic flow implemented in the previously developed MACH2 computer program. To increase...

Briefs: Physical Sciences
Magnetostrictively Actuated Valves for Cryosurgical Probes

In cryosurgical probes of a type now undergoing development, the flow of coolant (typically, liquid nitrogen) would be regulated by magnetostrictively actuated needle valves controlled by use of superconductive electromagnet coils. In comparison with cryosurgical probes now in use, the...

Briefs: Physical Sciences
Remote Sensing of Electric Fields in Clouds

A proposed method for remote sensing of the electric field in a cloud that contains ice crystals would exploit the relationship between (1) the polarization-dependent radiometric or radar brightness of the cloud and (2) the average or bulk orientation of the crystals as affected by the electric field....

Briefs: Physical Sciences

An improved method of infrared imaging of bulk defects in cadmium zinc telluride (CdZnTe) wafers has been developed. The method is intended primarily to be a means of identifying...

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Briefs: Physical Sciences

Compact image generators that contain illumination sources and electronically controlled spatial light modulators have been invented. Compactness is achieved by folding of the optical paths that link the...

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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...

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Briefs: Physical Sciences

Two major improvements, described below, have been made in the construction and operation of a computed-tomography imaging spectrometer (CTIS). These plus future improvements can be...

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