Fig. 5. Solution ³¹P nuclear magnetic resonance (NMR) spectra of alkaline extracts of swine manure extracted with different concentrations of NaOH (0.15, 0.25, and 0.50 M), and a constant concentration of 50 mM EDTA. All spectra are plotted using a line broadening of 1.0 Hz, except for the inset spectrum of the 0.50 M NaOH + 50 mM EDTA extract, which was plotted using a line broadening of 0.3 Hz to preserve the enhanced resolution obtained for this spectrum. The main spectra are scaled to show the largest orthophosphate monoester signal as 75% of the full height of the figure.