Special Coverage

Lightweight, Flexible Thermal Protection System for Fire Protection
High-Precision Electric Gate for Time-of-Flight Ion Mass Spectrometers
Polyimide Wire Insulation Repair System
Distributed Propulsion Concepts and Superparamagnetic Energy Harvesting Hummingbird Engine
Wet Active Chevron Nozzle for Controllable Jet Noise Reduction
Magnetic Relief Valve
Active Aircraft Pylon Noise Control System
Unmanned Aerial Systems Traffic Management

Lightweight, Low-Power, Inexpensive Ozone Dosimeters

Ozonolysis of organic dyes would cause color changes, which would be measured. Lightweight, low-power-consumption, inexpensive ozone sensors based on colorimetric chemical sensing would be developed, according to a proposal. Colorimetric chemical sensing is an established technique, but it has not been applied previously to sensing of ozone. The proposed ozone sensors could be incorporated into radiosondes for measuring tropospheric and stratospheric ozone concentrations; they could also be used to monitor ozone in a variety of indoor and outdoor environments near such ozone sources as electric-arc welding equipment, high-voltage laboratory instruments, photocopiers, laser printers, and electrostatic air cleaners.

Posted in: Briefs, TSP, Physical Sciences


Update on Electrolytes for Low-Temperature Lithium Cells

A report presents results of research on carbonate-based electrolytes to improve the low-temperature-performances of lithium-ion rechargeable electrochemical cells. The loss of performance with decreasing temperature is attributable largely to a decrease of ionic conductivity and the increase in viscosity of the electrolyte. What is needed to extend the minimum operating temperature from 20 °C down to –40 °C is a stable electrolyte solution with relatively large low-temperature conductivity, relatively small low-temperature viscosity, a large electric permittivity, adequate coordination behavior, and appropriate ranges of solubilities of liquid and salt constituents.

Posted in: Briefs, TSP, Materials


Noninvasive Test Detects Cardiovascular Disease

Spinal taps would no longer be necessary. A technique for noninvasive determination of the pressure in the cerebrospinal fluid (CSF) has been proposed. This technique would involve two main steps: First, an optical coherence tomographic scanner would be aimed into an eye and used to image the optical disk (see figure). Next, the resulting tomographic imagery would be digitized and processed to determine the thickness of the neural fiber layer, which thickness is known to increase with the CSF pressure.

Posted in: Briefs, TSP, Bio-Medical, Medical


Bushing-Mounted Drag Chain

A drag chain can be wrapped to a smaller radius than was previously possible. The figure illustrates a chair-base mechanism with a bushing-mounted drag chain. The bushing-mount design provides for one end of the drag chain to be free to pivot; this provision makes it possible to wrap the drag chain to a radius smaller than that achievable in mechanisms previously designed for the same purpose. The utility of mechanisms like this one lies in applications in which rotation of machinery involves significant turning radii, so that bending of cables that run through drag chains involve relatively tight arcs.

Posted in: Briefs, Mechanical Components, Mechanics


Improved Urine Preservative

This solution combines antibacterial and antioxidant properties. An improved solution for preserving samples of urine has been formulated. This solution preserves a much broader spectrum of analytes in urine than do other urine-preservative solutions here-tofore in use by NASA, and is safe for use by humans. When this solution is used, (1) refrigeration of urine samples is not necessary for preserving them and (2) the solution does not alter the pH values of the samples — two important considerations for collecting and storing urine samples in outer space. By eliminating the need to ship frozen samples, this preservative will enable the collection of urine samples — not only in outer space but also in terrestrial remote settings where it was previously not feasible.

Posted in: Briefs, Bio-Medical, Medical


Primers for Amplifying CMV DNA in Body Fluids and Tissue

A novel set of primers enables high-volume, rapid, inexpensive viral diagnostic testing. A novel set of primers has been developed for use in a polymerase chain reaction (PCR) to amplify the deoxyribonucleic acid (DNA) of cytomegalovirus (CMV). The purpose of this development is to enable faster, more sensitive detection of CMV virus infecting body fluids and tissues.

Posted in: Briefs, Bio-Medical, Medical


The Automated Fatigue Calculation Program (FATPLUS)

Since it was developed in the late 1980s, the Automated Fatigue Calculation Program (FATPLUS) has consistently demonstrated its ability to predict fatigue life, independently validate proprietary fatigue methodologies, identify fatigue-sensitive parts, and train engineers in predicting fatigue lives. FATPLUS enables its users to create, save, and modify specific stress spectra and properties of materials.

Posted in: Briefs, Software


The U.S. Government does not endorse any commercial product, process, or activity identified on this web site.