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The advent of a new vacuum ultraviolet (VUV) spectroscopic absorption detector for gas chromatography has enabled applications in many areas. Theoretical simulations of VUV spectra using computational chemistry can aid the new technique in situations where experimental spectra are unavailable. In this study, VUV spectral simulations of paraffin, isoparaffin, olefin, naphthene, and aromatic (PIONA) compounds using time-dependent density functional theory (TDDFT) methods were investigated. Important factors for the simulations, such as functionals/basis sets and formalism of oscillator strength calculations, were examined and parameters for future PIONA compound simulations were obtained by fitting computational results to experimental spectra. The simulations produced satisfactory correlations between experimental observations and theoretical calculations, and enabled potential analysis applications for complex higher distillate fuels, such as diesel fuel. Further improvement of the methods was proposed.
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Forecasting Equatorial Ionospheric Convective Instability With ICON Satellite Measurements
Key Points ICON satellite measurements used to force forecast simulations of plasma convective instability in the equatorial ionosphere Numerical simulations based on data from March 2022, were mainly accurate although there were some failures Significant improvements can be made to simulation initialization
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- Award ID(s):
- 2230365
- PAR ID:
- 10446724
- Date Published:
- Journal Name:
- Space Weather
- Volume:
- 21
- Issue:
- 5
- ISSN:
- 1542-7390
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1029/2023SW003427
