title: Partition chromatographic-gravimetric assay of opium.
mesh_terms: D002845:Chromatography; D004987:Ethers / Q000032:analysis; D005069:Evaluation Studies as Topic; D008722:Methods; D009020:Morphine / Q000032:analysis*; D009578:Nitrobenzenes / Q000032:analysis; D009892:Opium / Q000032:analysis*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D004987:Ethers; D009578:Nitrobenzenes; D009020:Morphine; D009892:Opium