The analytical and data processing methodology have been described in Wozniak et al. (2013, 2015). The full citations for these references are below. A summary of the methods is quoted here:
Aerosol WSOM was minimally diluted with D2O and analyzed on a Bruker Biospin Avance III 400 MHz NMR with a broadband inverse solution state probe at ODU’s College of Sciences Major Instrumentation Cluster facility using a water suppression technique described previously (e.g., Wozniak et al., 2013). WSOM samples were diluted to a final composition of 9:1 sample:D2O and 500 µL of this solution was added to 5 mm glass NMR tubes and analyzed without further manipulation. Spectra were acquired using a 2 s recycle delay, a 119 ms acquisition time, a time domain of 16 k, and co-adding 8000 scans. The summed free induction decay signal was exponentially multiplied and zero-filled once. The spectra were processed with a line broadening of 3 Hz.
* During data processing for publications from this work (Wozniak et al., 2013, 2015), spectral chemical shifts corresponding to potential solvent interferences from hydrogens in residual water (region excluded: 4.6 ppm to 4.8 ppm), methanol (region excluded: 3.28 ppm to 3.46 ppm), and tetramethylsilane (region excluded: <0.095 ppm) were set to 0. The data archived here do not have these sections set to 0.
** The data for samples 7587, 8044, and 8045 have been flagged as bad and are not included here. Multiple attempts were made to rerun these samples, but adequate spectra were not obtained.
References:
Wozniak, A. S., R. L. Sleighter, H. Abdulla, A. S. Priest, P. L. Morton, R. U. Shelley, W. M. Landing, and P. G. Hatcher. 2013. Relationships among aerosol water soluble organic matter, iron and aluminum in European, North African, and Marine air masses from the 2010 US GEOTRACES cruise. Marine Chemistry, 154, 24-33. doi:10.1016/j.marchem.2013.04.011
Wozniak, A. S., R. U. Shelley, S. M. McElhenie, A. S. Willoughby, W. M. Landing, P. G. Hatcher. 2015. Insights into potential Fe-binding aerosol water soluble organic ligands from the 2011 US GEOTRACES cruise. Marine Chemistry, 173, 162-172, doi:10.1016/j.marchem.2014.11.002