We examined physiological adaptations which allow the psychrotroph Rhodococcus sp. strain Q15 to assimilate alkanes at a low temperature (alkanes are contaminants which are generally insoluble and/or solid at low temperatures). During growth at 5 degrees C on hexadecane or diesel fuel, strain Q15 produced a cell surface-associated biosurfactant(s) and, compared to glucose-acetate-grown cells, e...

A study of detonations in high-molecular weight hydrocarbon fuels of interest to pulse detonation engine applications was performed in a 280 mm diameter, 7.3 m long facility. Detonation pressure, wave speed, and cell width measurements were made in JP-10 mixtures and in mixtures representative of the decomposition products of JP-10. Experiments were performed in vapor-phase JP-10 mixtures at 35...

A study of detonations in high molecular weight hydrocarbon fuels was performed in two GALCIT facilities: the 280 mm gaseous detonation tube (GDT) and a 1180 liter vessel (HYJET) with jet initiation capability. In the GDT, detonation pressure, wave speed and cell width measurements were made in hexane-oxygen-nitrogen mixtures with and without the addition of lower molecular weight fuels. Stoich...

Proton exchange membrane fuel cells typically consist of stacks of membrane electrode assemblies sandwiched between bipolar plates, effectively combining the individual cells in series to achieve the desired voltage levels. Elastomeric gaskets are commonly used between each cell to insure that the reactant gases are isolated; any failure of a fuel cell gasket can cause the reactants to mix, whi...

Solid oxide fuel cells (SOFC) are receiving an increasing level of attention for both smalland large-scale applications due their high fuel flexibility compared to other types of fuel cells. This article reviews recent work in SOFC materials research, with an emphasis on anodes that can directly utilize hydrocarbon fuels.

This paper presents an overview of the synthesis, chemical and electrochemical properties, and polymer electrolyte fuel cell applications of new proton-conducting polymer electrolyte membranes based on hydrocarbon polymers. Due to their chemical stability, high degree of proton conductivity, and remarkable mechanical properties, per ̄uorinated polymer electrolytes such as Na®on, Aciplex, Flemion...

NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, o...

While NASA’s current next-generation launch vehicle research has largely focused on advanced allrocket single-stage-to-orbit vehicles (i.e. the X-33 and it’s RLV operational follow-on), some attention is being given to advanced propulsion concepts suitable for “next-generation-and-a-half” vehicles. Rocketbased combined-cycle (RBCC) engines combining rocket and airbreathing elements are one cand...

homogenous charge compression ignition (hcci) combustion is spontaneous multi-site combustion of a nominally premixed air/fuel mixture that exhibits high rate of pressure rise and short combustion duration. to avoid excessive pressure rise rate and knocking, hcci engines are fueled with highly diluted mixture using a combination of excess air and/or egr. hcci combustion is attractive due to ext...