{"action": "optimize", "device": [""], "output": "chromatography solvent"}
{"action": "prepare", "output": "", "reagent": ["chromatography solvent", "isobutanol"]}
{"action": "seal", "output": "solvent vapors", "temperature": [""], "time": ["at least 1 h"]}
{"action": "pin", "container": ["chromatography paper"], "output": "", "reagent": ["", "solvent vapors"]}
{"action": "determine", "device": [""], "output": "separated compounds"}
{"action": "draw", "device": ["a graphite pencil (starting line)"], "length": ["a line"], "output": ""}
{"action": "repeat", "concentration": ["a concentrated spot"], "output": "urocanic acid"}
{"action": "produce", "output": "", "reagent": ["urocanic acid"]}
{"action": "place", "container": ["the prepared strip"], "output": "the chromatogram"}
{"action": "seal", "container": ["the chamber"], "output": "", "reagent": ["separated compounds"]}
{"action": "remove", "container": ["the strip"], "output": ""}
{"action": "dry", "device": [""], "output": "imidazolyl derivatives"}
{"action": "rinse", "output": "", "reagent": ["imidazolyl derivatives", "the Pauly diazo reagent"]}
{"action": "calculate", "container": ["the solvent"], "output": "Rf values"}