SimilarityRank
sulphur 0.902 6647
carbon 0.897 3195
nitrogen 0.878 6386
monoxide 0.848 12904
emission 0.820 3620
hydrocarbon 0.815 12320
oxide 0.813 7892
co2 0.812 18793
nitrous 0.805 29606
nox 0.801 28969
&sub2; 0.800 34174
tetrachloride 0.794 38419
methane 0.794 11786
particulate 0.793 25930
pollutant 0.778 10281
chlorine 0.772 10537
cfc 0.771 9251
nitric 0.771 22052
chlorofluorocarbon 0.759 24061
vocs 0.758 67555
photochemical 0.755 30345
ethane 0.749 70857
phosgene 0.748 98640
benzene 0.748 21692
ozone 0.746 5037