actias luna adsorption aldehyde american and british english spelling differences ammonia anecdotal evidence aroma compound aromatherapy assay atmosphere bee bee learning and communication body odor cen chemical compound chemisorption deodorant digital object identifier dipole electronic nose energy ferrous flavorist gas gender germany heterogeneous catalysis hive humidity hydrogen sulfide ketone machine olfaction mechanical meteorology molecule moth multivariate analysis n-butanol neural network nonanal olfaction olfactory fatigue olfactory receptor olfactory system organic compound perfume perfumer pheromone physisorption ramparts refinery science sense sewage treatment smell solid subjectivity teflon temperature transmission vapor pressure vomeronasal organ wiktionary