羥自由基

自 = 丶 + 目 : Mnemonic symbol: a hand mirror, which someone uses to look at themselves.

The Eye of Providence (目) is looking at itself (自) in a handheld mirror (自) in the space station's bathroom (Ø4). It think it's indeed looking very good, since Zorro (z) attached a petal (丶) to its eye (目).

由 = 丨 + 曰 : Mnemonic symbol: 自由古巴， a cuba libre. The character 由 itself even looks like a cuba libre.

Maud Younger (y) is taking part in a charity auction in the outhouse's kitchen (ou2). She is auctioning the dinosaur bone (丨) next to her and is speaking into a microphone (曰). In the other hand she is holding a cuba libre (由), and she is already quite drunk.

基 = 其 + 土 : Joan of Arc (ji) has to repair the watchtower (其) In front of the space station (Ø1). The tower needs a new foundation (基), and because it is floating in outer space, Joan of Arc can just add some dirt (土) to its base (基) to create a new foundation.