Tech Briefs

Electronic heat-transfer devices of a proposed type would exploit some of the quantum-wire-like, pseudo-superconducting properties of single-wall carbon nanotubes or, optionally, room- temperature- superconducting polymers (RTSPs). The devices are denoted thermo-electron ballistic (TEB) coolers or...

Proton collimators have been proposed for incorporation into inertial- electrostatic- confinement (IEC) fusion reactors. Such reactors have been envisioned as thrusters and sources of electric power for spacecraft and as sources of energetic protons in commercial ion-beam applications. An artist's concept...

A floating apparatus denoted a temperature probe aquatic suspension system (TPASS) has been developed for measuring the temperature of an ocean, lake, or other natural body of water at predetermined depths. These types of measurements are used in computer models to relate remotely sensed...

Three computer programs have been written to preprocess digitized outputs of sensors during rocket-engine tests at Stennis Space Center (SSC). The programs apply exclusively to the SSC "E" test-stand complex and utilize the SSC file format. The programs are the following:

An optoelectronic apparatus has been invented as a noninvasive means of measuring the concentration of glucose in the human body. The apparatus performs polarimetric and interferometric measurements of the human eye to acquire data from which the concentration of glucose in the aqueous...

An optoelectronic system has been developed for measuring heights, above a floor, of designated points on a large object. In the original application for which the system was conceived, the large object is a space shuttle and the designated points are two front and two rear points for the...

A method of detecting bacterial spores incorporates

Miniature, relatively inexpensive microbioanalytical systems ("laboratory-on-a-chip" devices) have been proposed for the detection of hazardous microbes and toxic chemicals. Each system of this type would include optoelectronic sensors and sensor-output-processing circuitry that would...

A combination of pulsed-source interferometry and acoustic diffraction has been proposed for use in imaging subsurface microscopic defects and other features in such diverse objects as integrated-circuit chips, specimens of materials, and mechanical parts. A specimen to be inspected by this...

A method of measuring the fraction of bacterial spores in a sample that remain viable exploits DPA-triggered luminescence of Tb³⁺ and is based partly on the same principles as those described in the immediately preceding article. Unlike prior methods for performing...

This report presents a study of dissipation (irreversible production of entropy) in three-dimensional, temporal mixing layers laden with evaporating liquid drops. The purpose of the study is to examine the effects of evaporating drops on the development of turbulent features in flows....

Efforts are under way to develop a special class of thin-shell curved mirrors for high-resolution imaging in visible and infrared light in a variety of terrestrial or extraterrestrial applications. These mirrors can have diameters of the order of a meter and include metallic film...

The Mars Cost Tracking Model is a computer program that administers a system set up for tracking the costs of future NASA projects that pertain to Mars. Previously, no such tracking system existed, and documentation was written in a variety of formats and scattered in various places. It was difficult...

Tcast2 is a FORTRAN computer program that accelerates the setup of a process in which a slurry containing metal particles and a polymeric binder is cast, to a thickness regulated by a doctor blade, onto fibers wound on a rotating drum to make a “green” precursor of a metal-matrix/fiber composite...

Sports-related injuries are a common cause of damaged ligaments and tendons in shoulders, knees, wrists, elbows and ankles, and can usually be repaired through arthroscopic surgery. Through an incision no larger than a keyhole, a surgeon inserts an endoscope to see inside the joint on a video...

A laboratory method has been devised to enable measurement of the concentration of iron bound in ferritin from small samples of blood (serum). Derived partly from a prior method that depends on large samples of blood, this method involves the use of an inductively coupled plasma mass...

Arrays of electrodes integrated with chip-scale packages and silicon-based integrated circuits have been proposed for use as medical electronic implants, including neuro-prosthetic devices that might be implanted in brains of patients who suffer from strokes, spinal-cord injuries, or...

The term "common/dependent pressure vessel" (C/DPV) denotes a proposed alternative configuration for a nickel-hydrogen battery. The C/DPV configuration is so named because it is a hybrid of two prior configurations called "common pressure vessel" (CPV) and...

Capacitors capable of storing energy at high densities are being developed for use in pulse-power circuits in such diverse systems as defibrillators, particle-beam accelerators, microwave sources, and weapons. Like typical previously developed energy-storage capacitors, these capacitors are made from pairs of...

Eroding potentiometers have been devised for measuring the time-dependent positions of char fronts advancing through layers of insulating material subject to intense heating from one side. In the original application, the material layers of interest are thermal insulators in rocket motors and the heat comes from firing of...

An improved method of designing and fabricating laminated composite-material (matrix/fiber) structures containing embedded shape-memory-alloy (SMA) actuators has been devised. Structures made by this method have repeatable, predictable properties, and fabrication processes can...

An improved approach to the mathematical modeling of feedback control of thermal networks has been devised. Heretofore software for feedback control of thermal networks has been developed by time-consuming trial-and-error methods that depend on engineers' expertise. In contrast, the present approach...

A methodology is emerging from efforts to design a mission operations facility.

A methodology for designing operational facilities for collaboration by multiple experts has begun to take shape as an outgrowth of a project to design such facilities for scientific operations of the planned...

Artifacts that are fabricated with the help of molecular-beam epitaxy (MBE) are undergoing development for use as dimensional calibration standards with sub-micron widths. Such standards are needed for calibrating instruments (principally, scanning electron microscopes and scanning probe...

A process for growing protein crystals encapsulated within membranes has been invented. This process begins with the encapsulation of a nearly saturated aqueous protein solution inside semipermeable membranes to form microcapsules. The encapsulation is effected by use of special formulations of a...

Electrode materials that exhibit mixed conductivity (that is, both electronic and ionic conductivity) have been investigated in a continuing effort to improve the performance of the alkali metal thermal-to-electric converter (AMTEC). These electrode materials are intended primarily for use on...

A mechanical amplifier has been devised to multiply the stroke of a piezoelectric transducer (PZT) intended for use at liquid helium temperatures. Interferometry holds the key to high angular resolution imaging and astrometry in space. Future space missions that will detect planets around other...

A method of testing explosive and pyrotechnic devices involves exploding the devices inside swell sleeves. Swell sleeves have been used previously for measuring forces. In the present method, they are used to obtain quantitative indications of the energy released in explosions of the devices under...

NASA Dryden Flight Research Center's new Propulsion Flight Test Fixture (PFTF), designed in house, is an airborne engine-testing facility that enables engineers to gather flight data on small experimental engines. Without the PFTF, it would be necessary to obtain such data from traditional wind tunnels, ground test...

A paper presents a theoretical investigation of subsonic and supersonic effects in a Bose-Einstein condensate (BEC). The BEC is represented by a time-dependent, nonlinear Schroedinger equation that includes terms for an external confining potential term and a weak interatomic repulsive...