Chapter 5
shows photographs of three samples after 24 h having equilibrium pH values
ranging from 5.0 to 8.5. As pH decreases, the water layer becomes more
transparent.
Before adding HCI (-10 min, pH 8.8) Adding HCI (0 min)
1 min after adding HCI 3 min after adding HCI
5 min after adding HCI 7 min after adding HCI (pH 4.5)
(The scale bar is 20 μm)
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