References
- Hand, J.L., S.A. Copeland, D.E. Day, A.M. Dillner, H. Indresand, W.C. Malm, C.E. McDade, et al. 2011. Spatial and seasonal patterns and temporal variability of haze and its constituents in the United States: Report V June 2011. Cooperative Institute for Research in the Atmosphere. http://vista.cira.colostate.edu/Improve/spatial-and-seasonal-patterns-and-temporal-variability-of-haze-and-its-constituents-in-the-united-states-report-v-june-2011/.
- Hyslop, N.P., K. Trzepla, and W.H. White. 2012. Reanalysis of archived improve PM2.5 samples previously analyzed over a 15-year period. Environ. Sci. Technol. 46 (18):10106–13. doi:10.1021/es301823q.
- Hyslop, N.P., K. Trzepla, and W.H. White. 2015. Assessing the suitability of historical PM2.5 element measurements for trend analysis. Environ. Sci. Technol. 49 (15):9247–55. doi:10.1021/acs.est.5b01572.
- Hyslop, N.P., and W.H. White. 2008. An empirical approach to estimating detection limits using collocated data. Environ. Sci. Technol. 42 (14):5235–40. doi:10.1021/es7025196.
- Hyslop, N.P., and W.H. White. 2009. Estimating precision using duplicate measurements. J. Air Waste Manag. Assoc. 59 (September):1032–39. doi:10.3155/1047-3289.59.9.1032.
- Indresand, H., and A.M. Dillner. 2012. Experimental characterization of sulfur interference in improve aluminum and silicon XRF data. Atmos. Environ. 61 (December):140–47. doi:10.1016/j.atmosenv.2012.06.079.
- Malm, W.C., B.A. Schichtel, R.B. Ames, and K.A. Gebhart. 2002. A 10-year spatial and temporal trend of sulfate across the United States. J. Geophys. Res.: Atmos 107 (D22):ACH 11-1–ACH 11–20. doi:10.1029/2002JD002107.
- Malm, W.C., B.A. Schichtel, M.L. Pitchford, L.L. Ashbaugh, and R.A. Eldred. 2004. Spatial and monthly trends in speciated fine particle concentration in the United States. J. Geophys. Res. 109 (D3). doi:10.1029/2003JD003739.
- Murphy, D.M., J.C. Chow, E.M. Leibensperger, W.C. Malm, M. Pitchford, B.A. Schichtel, J.G. Watson, and W.H. White. 2011. Decreases in elemental carbon and fine particle mass in the United States. Atmos. Chem. Phys. 11 (10):4679–86. doi:10.5194/acp-11-4679-2011.
- Seinfeld, J.H., and S. Pandis. 1998. Atmospheric chemistry and physics. New York: John Wiley & Sons.
- Sen, P.K. 1968. Estimates of regression coefficient based on Kendall's tau. J. Am. Stat. Assoc. 63 (324):1379–89. doi:10.1080/01621459.1968.10480934.
- Taylor, S.R., and S.M. McLennan. 1995. The geochemical evolution of the continental crust. Rev. Geophys. 33 (2):241–65. doi:10.1029/95RG00262.
- UC Davis. 2010. Data report for elemental analysis of IMPROVE samples collected during January, February, March 2009. Davis, California: University of California. http://vista.cira.colostate.edu/improve/Data/QA_QC/QAQC_UCD.htm
- Vekemans, B., K. Janssens, L. Vincze, F. Adams, and P. Van Espen. 1994. Analysis of X-ray spectra by iterative least squares (AXIL): New developments. X-Ray Spectr. 23 (6):278–85. doi:10.1002/xrs.1300230609.
- White, W.H. 1997. Deteriorating air or improving measurements? On interpreting concatenate time series. J. Geophys. Res. 102 (D6):6813–21. doi:10.1029/97JD00030.
- White, W.H. 2006. S interference in XRF determination of Si. http://vista.cira.colostate.edu/improve/Data/QA_QC/Advisory/da0011/da0011_S_Si.pdf.
- White, W.H. 2008a. Bias between masked and unmasked elemental measurements. http://vista.cira.colostate.edu/improve/Data/QA_QC/Advisory/da0019/da0019_masks.pdf.
- White, W.H. 2008b. Chemical markers for sea salt in IMPROVE aerosol data. Atmos. Environ. 42 (January):261–74. doi:10.1016/j.atmosenv.2007.09.040.
- White, W.H. 2010. Marginal detection of heavy elements by PIXE analysis. http://vista.cira.colostate.edu/improve/Data/QA_QC/Advisory/da0026/da0026_DA_PIXE_Mo.pdf.
- White, W.H. 2017. Over-reporting of sodium in salt-rich samples. http://vista.cira.colostate.edu/improve/Data/QA_QC/Advisory/da0037/da0037_Na_matrix.pdf.
- White, W.H., L.L. Ashbaugh, N.P. Hyslop, and C.E. McDade. 2005. Estimating measurement uncertainty in an ambient sulfate trend. Atmos. Environ. 39 (36):6857–67. doi:10.1016/j.atmosenv.2005.08.002.
- Yatkin, S., K. Trzepla, W.H. White, N.J. Spada, and N.P. Hyslop. 2020. Development of single-compound reference materials on polytetrafluoroethylene filters for analysis of aerosol samples. Spectrochim. Acta Part B. 171 (September):105948. doi:10.1016/j.sab.2020.105948.