Materials

It is currently not possible to perform simulations of turbulent reactive flows due in particular to complex chemistry, which may contain thousands of reactions and hundreds of species. This complex chemistry results in additional differential equations, making the numerical solution of...

A computer model simulates reactional gas/liquid two-phase flow processes in porous media. A typical process is the oxygen/wastewater flow in the Volatile Removal Assembly (VRA) in the Closed Environment Life Support System (CELSS) installed in the International Space Station (ISS). The...

This technology produces a silica glass material with a promising negative refractive index. The material changes volume via irradiation under UV light, and results in a refractive index capability of 10-2. This makes it applicable to a wide range of fields, including holograms, optical memory, digital...

Future NASA missions aimed at exploring Mars, the Moon, and the outer planets require rechargeable batteries that can operate over a wide temperature range (–60 to +60 °C) to satisfy the requirements of various applications. In addition, many of these applications...

A novel, high-efficiency gas particulate filter has precise particle size screening, low pressure drop, and a simple and fast regeneration process. The regeneration process, which requires minimal material and energy consumption, can be completely automated, and the filtration performance can be...

A “simplified shear solution” method approximates the through-thickness shear stress distribution within a composite laminate based on an extension of laminated beam theory. The method does not consider the solution of a particular boundary value problem; rather, it requires only knowledge of...

A new solar-cell structure utilizes a single, ultra-wide well of either gallium arsenide (GaAs) or indium-galliumphosphide (InGaP) in the depletion region of a wide bandgap matrix, instead of the usual multiple quantum well layers. These InGaP barrier layers are effective at reducing diode dark current, and...

A new technique for carbon nanotube oxidation was developed based upon the photo-oxidation of organic compounds. The resulting method is more benign than conventional oxidation approaches and produces single-wall carbon nanotubes (SWCNTs) with higher levels of oxidation.

A recently discovered superconductor, magnesium diboride (MgB2), can be used to fabricate conducting leads used in cryogenic applications. Discovered to be superconducting in 2001, MgB2 has the advantage of remaining superconducting at higher temperatures than the previously used material, NbTi. The purpose of these...

Polyimide aerogels with three-dimensional cross-linked structure are made using linear oligomeric segments of polyimide, and linked with one of the following into a 3D structure: trifunctional aliphatic or aromatic amines, latent reactive end caps such as nadic anhydride or...

Aerogels that consist, variously, of neat silica/polymer alloys and silica/polymer alloy matrices reinforced with fibers have been developed as materials for flexible thermal-insulation blankets. In comparison with prior aerogel blankets, these aerogel blankets are more durable and less...

NASA PS400 is a solid lubricant coating invented for high-temperature tribological applications. This plasma-sprayed coating is a variant of the previously patented PS304 coating, and has been formulated to provide higher density, smoother surface finish, and better dimensional stability.

Exfoliated graphite nanoflakes are a potential low-cost source of nano-reinforcement for making polymer composites with unique properties. The chemical nature of the graphitic surface leads to a low-surface energy as produced. This makes the nanoflakes...

MicroGel® is a unique, highly porous xero-gel silica formed using sol-gel techniques. The starting materials used are designed per guidance from molecular dynamic calculations, and are made up of mixed alkali silicates rather than normally used single alkali silicates that are gelled with...

In the development of advanced aircraft-engine fan cases and containment systems, composite materials are beginning to be used due to their low weight and high strength. The design of these structures must include the capability of withstanding impact loads from a released...

In many applications, it is highly desirable to operate a CO2 laser in a sealed condition, for in an open system the laser requires a continuous flow of laser gas to remove the dissociation products that occur in the discharge zone of the laser, in order to maintain a stable power output. This adds to the...

Titanium hydroxide, TiO(OH)2 (g), has been identified as the primary reaction product of TiO2 (s) + H2O (g) at high temperatures (1,200–1,400 °C) through the use of the transpiration technique. This technique is a well-established method used to measure equilibrium pressures at 1 atm....

An improved protocol for thermo-gravimetric analysis (TGA) of samples of single-wall carbon nanotube (SWCNT) material has been developed to increase the degree of consistency among results so that meaningful comparisons can be made among different samples. This improved TGA protocol is...

SafetyChem is a computer program that maintains a relational database for tracking chemicals and associated hazards at Johnson Space Center (JSC) by use of a Web-based graphical user interface. The SafetyChem database is accessible to authorized users via a JSC intranet. All new chemicals pass...

A number of experimental lithium-ion cells, consisting of MCMB (meso-carbon microbeads) carbon anodes and LiNi0.8Co0.2O2 cathodes, have been fabricated with increased safety and expanded capability. These cells serve to verify and demonstrate the reversibility, low-temperature...

Complex material behavior is represented by a single equation of product form to account for interaction among the various factors. The factors are selected by the physics of the problem and the environment that the model is to represent. For example, different factors...

Electrostrictive ceramic actuators that can function at low temperatures have been developed for controlling the shapes of mirrors in the Next Generation Space Telescope (NGST). On Earth, electrostrictive ceramic actuators may be useful for fine control of the positions of objects in...

As part of the continuing efforts to develop advanced electrolytes to improve the performance of lithiumion cells, especially at low temperatures, a number of electrolyte formulations have been developed that result in improved low-temperature performance (down to –60...