Briefs: Materials
Processable Polyimides Containing APB and Reactive End Caps

Imide copolymers that contain 1,3-bis (3- aminophenoxy) benzene (APB) and other diamines and dianhydrides and that are terminated with appropriate amounts of reactive end caps have been invented. The reactive end caps investigated thus far include 4-phenylethynyl phthalic anhydride...

Briefs: Materials
Liquid Coatings for Reducing Corrosion of Steel in Concrete

Inorganic coating materials are being developed to slow or stop corrosion of reinforcing steel members inside concrete structures. It is much simpler and easier to use these coating materials than it is to use conventional corrosion-inhibiting systems based on impressed electric...

Briefs: Materials
Less-Toxic Coatings for Inhibiting Corrosion of Aluminum

Two recently invented families of conversion- coating processes have been found to be effective in reducing or preventing corrosion of aluminum alloys. These processes offer less-toxic alternatives to prior conversion-coating processes that are highly effective but have fallen out of favor...

Briefs: Materials

A novel class of polymer/clay nanocomposites has been invented in an attempt to develop transparent, lightweight, durable materials for a variety of aerospace applications. As their name...

Briefs: Mechanical & Fluid Systems

A control valve that can throttle high-pressure cryogenic fluid embodies several design features that distinguish it over conventional valves designed for...

Briefs: Mechanical & Fluid Systems

The flight-test community routinely spends considerable time and money to determine a range of flight conditions, called a flight envelope, within which an aircraft is safe to fly. The...

Briefs: Mechanical & Fluid Systems

The Aerostructures Test Wing (ATW) was an apparatus used in a flight experiment during a program of research on aeroelastic instabilities. The ATW experiment was performed to study a specific instability known as...

Briefs: Software
Predicting Accumulations of Ice on Aerodynamic Surfaces

LEWICE is a computer program that predicts the accumulation of ice on two-dimensional aerodynamic surfaces under conditions representative of the flight of an aircraft through an icing cloud. The software first calculates the airflow surrounding the body of interest, then uses the airflow...

Briefs: Medical

An improved computational-simulation system for interactive medical imaging has been invented. The system displays high-resolution, three-dimensional-appearing images of anatomical objects based on...

Briefs: Medical

Fossils of primates and early humans exhibit great diversity in the size and shape of the jaw, teeth, and facial skeleton. Anthro- pologists theorize that these different skull...

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...

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: Mechanical & Fluid Systems

Modifications have been proposed to effect further improvement of the device described in “Improved Piezo- electrically Actuated Microvalve” (NPO-30158), NASA Tech Briefs, Vol....

Briefs: Mechanical & Fluid Systems

A proposed normally-closed microvalve would contain a piezoelectric bending actuator instead of a piezoelectric linear actuator like that of the microvalve described in the preceding...

Briefs: Mechanical & Fluid Systems

Designers of deep submersibles are reluctant to use conventional shafts and seals to penetrate the hulls of deep submersible, pressure vessels fearing seal...

Briefs: Mechanical & Fluid Systems

The figure depicts the aspects of a proposed deceleration-limiting design for crash walls at the sides of racetracks and highways. The proposal is intended to overcome the dis- advantages...

Briefs: Electronics & Computers

Figure 1 shows a three-stage monolithic microwave integrated circuit (MMIC) power amplifier that features high-electron-mobility transistors (HEMTs) as gain elements. This amplifier is designed to...

Briefs: Electronics & Computers

An apparatus that is extremely effective in dispensing a wide range of droplets has been developed. This droplet dispenser is unique in that it utilizes a droplet bias voltage, as well as an ionization pulse,...

Briefs: Electronics & Computers
Network Extender for MIL-STD-1553 Bus

An extender system for MIL-STD-1553 buses transparently couples bus components at multiple developer sites. The bus network extender is a relatively inexpensive system that minimizes the time and cost of integration of avionic systems by providing a convenient mechanism for early testing without the need to...

Briefs: Electronics & Computers

Some prototype parts of a digital beam-forming (DBF) receiver that would operate at multigigahertz carrier frequencies have been developed. The beam-forming algorithm in a DBF...

Briefs: Electronics & Computers

The Real-Time Interferometer Control Systems Testbed (RICST) timing board is a VersaModule Eurocard (VME)-based board that can generate up to 16 simultaneous, phase-locked timing signals at a rate...

Briefs: Software
Numerical Modeling of Nanoelectronic Devices

Nanoelectronic Modeling 3-D (NEMO 3-D) is a computer program for numerical modeling of the electronic structure properties of a semiconductor device that is embodied in a crystal containing as many as 16 million atoms in an arbitrary configuration and that has overall dimensions of the order of tens...

Briefs: Electronics & Computers

A proposed tracking receiver system containing three suitably positioned antenna elements and special signal-processing equipment would determine the direction of incidence of a...

Briefs: Information Technology

An improved method of analysis of coverage of areas of the Earth by a constellation of radio-communication or scientific-observation satellites has been developed. This method is...

Briefs: Information Technology
Update on EMD and Hilbert-Spectra Analysis of Time Series

U.S. Patent 6,381,559 presents further information about the method described in "Analyzing Time Series Using EMD and Hilbert Spectra" (GSC-13817), NASA Tech Briefs, Vol. 24, No. 10 (October 2000), page 63. To recapitulate: The method is especially well suited for analyzing time-series...

Briefs: Mechanical & Fluid Systems
Quasi-Sun-Pointing of Spacecraft Using Radiation Pressure

A report proposes a method of utilizing solar-radiation pressure to keep the axis of rotation of a small spin-stabilized spacecraft pointed approximately (typically, within an angle of 10° to 20°) toward the Sun. Axisymmetry is not required. Simple tilted planar vanes would be attached...

Briefs: Mechanical & Fluid Systems
Cable-Dispensing Cart

A versatile cable- dispensing cart can support as many as a few dozen reels of cable, wire, and/or rope. The cart can be adjusted to accommodate reels of various diameters and widths, and can be expanded, contracted, or otherwise reconfigured by use of easily installable and removable parts that can be carried onboard....

Briefs: Mechanical & Fluid Systems
Device for Locking a Control Knob
A simple, effective, easy-to-use device locks a control knob in a set position. In the initial application for which this device was conceived, the control knob to be locked is that of a needle valve. Previously, in that application, it was necessary for one technician to hold the knob to keep the valve at the...

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