Table 2. Air/Solution Interfacial Profiles Formed at Air Bubbles Deposited on PTFE Substrates.

solution	step thickness (nm)	force amplitude (nN)	surface distance (nm)
NaCl 1.0 M	8	0.125	11.2
	2.4	1.15	3.2
	0.8	0.45	0.8
NaF 0.154 M	8	0.8	20
	12	3.5	12
KCl 0.154 M	24	3	44
	16	7.5	20
	4	9	4
NaBr 0.154 M	20	0.75	20
NaI 0.154 M	20	1.4	32
	12	2.2	12
NaCl 1.0 M	24	2	24
NaCl 0.154 M	48	3	48