A final polish is usually provided by acid dipping.
Blanching (cleaning) of the blanks by an acid dip was necessary before striking to produce an acceptable surface if oxidation had occurred during annealing.
The surface energy was remarkably subsided by acid dipping duration.
The lowest roughness (Sa: 0.96 ± 0.29 nm) was observed for the highest acid dipping duration (1800 s).
Here, chemical surface treatment by electropolishing and acid dipping is used for improving surface properties of 316L stainless steel to provide a homogenous, smooth and corrosion resistant surface with high biocompatibility profile.
A magnesium stick composed of 90% Mg, 9% alminium and 1% zinc (6 mm diameter, 10 cm length, Nakagawa Metal, Japan) was surface-cleaned with 0.1 N acetic acid and dipped into pure water for about 1 minute.
"Saving Africa's Witch Children" follows Gary Foxcroft, founder of the charity Stepping Stones Nigeria, as he travels the rural state of Akwa Ibom, rescuing children abused during horrific "exorcisms" — splashed with acid, buried alive, dipped in fire — or abandoned roadside, cast out of their villages because some itinerant preacher called them possessed.
He looks like he's been quickly dipped in acid; things fell off, skin was removed.
Here he walks on one of his preferred materials -- large, thick slabs of Styrofoam, in this case white -- wearing shoes dipped in acid.
Most tellingly, Rip, the young kids' drug dealer in the first book, is still offering the service now, although they fail to recognise him, not because of ageing but his cosmetic attempts to avoid it: "It's a face mimicking a face... he looks like he's been quickly dipped in acid; things fell off, skin was removed".
