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Results for “cavity”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 451 records · Page 25
All sourcesNASA NTRSDOE OSTI
NASA NTRS1966

Time history of the magnetospheric cavity.

Cyclotron radius, magnetospheric boundary and Debye length scaling parameters for magnetospheric cavity arising from solar wind- induced geomagnetic storm and visibility of quasi- Van Allen belts

VAN ALLEN BELT↗
NASA NTRS1995

Vibration Method for Tracking the Resonant Mode and Impedance of a Microwave Cavity

There has been a concerted effort to improve the microwave heating technique for processing materials at high temperature. Improved optimization of the energy transfer from a microwave source to the material being processed is required. A vibration technique is pre- sented to continuously maintain a mode resonance and impedance match between a constant frequency magnetron source and a resonant cavity.

microwave↗
NASA NTRS2019

Cavity Ring Down Spectroscopy of Cold Neutral Phenanthrene and Phenanthridine in Supersonic Jets

Here we study the effect of nitrogen insertion on the electronic spectra of polycyclic aromatic hydrocarbon (PAH) molecules measured under laboratory conditions that are relevant for comparison with astronomical data. We examine the case of the substitution of carbon atoms by nitrogen atoms in the benzenoid skeleton of phenanthrene (C 14 H 10 ), a prototype non-compact PAH. The vibronic transitions of the 2 1 A 1 (S 1 )←X 1 A 1 (S 0 ) electronic absorption band system of neutral phenanthrene (C 14 H 10 ) and phenanthridine (C 13 H 9 N) molecules seeded in a supersonic free jet expansion of argon gas are measured in the 315-345 nm region using the cavity ring down spectroscopy (CRDS) technique. Additional measurements of the absorption spectra of the phenanthrene, phenanthridine, and 1,10-phenanthroline (C 12 H 8 N 2 ) molecules isolated in 10-K solid argon matrices are also presented. The results obtained confirm that laboratory spectra of cold, isolated molecules obtained under astrophysically relevant conditions are required for a direct, unambiguous comparison with astronomical observations as well as for the understanding of the physical evolution of the interstellar medium.

Absorption band↗