Table 1. Effects of Solution pH and Salinity on Intensity Weighted Hydrodynamic Diameter Size Distribution, UV–Vis–NIR Extinction Ratios, and Weight Percent of Organic Carbon on the Nanoclusters.

pH–[NaCl]	initial NaCl conc (mM)	DLS intensity weighted size distributions (nm) (cumulative size, %)	A800/A525	wt % organic carbon (from TOC)
5–0	0	5–40 (23)	0.825	26.9 ± 0.6
		40–100 (25)
		100–250 (52)
5–17	17	5–40 (18)	0.635	20.7 ± 0.9
		40–100 (22)
		100–250 (60)
5–33	33	5–40 (12)	0.619	17.9 ± 0.7
		40–100 (19)
		100–250 (69)
7–0	0	5–40 (9)	0.728	24.3 ± 0.5
		40–100 (62)
		100–250 (29)
7–17	17	5–40 (20)	0.501	20.2 ± 0.5
		40–100 (52)
		100–250 (28)
7–33	33	5–40 (20)	0.419	19.4 ± 0.3
		40–100 (4)
		100–250 (76)