ratios were computed to be very low (0.
The compounds mainly fall into the following 12 aromatic hydrocarbon series: naphthalene (m/z 128, m/z 142, m/z 156, m/z 170, m/z 184, m/z 198), phenanthrene (m/z 178, m/z 192, m/z 206, m/z 220), benzopyrene (m/z 252), fluoranthene (m/z 202, m/z 216), dibenzothiophene (m/z 184, m/z 198, m/z 212, m/z 226), benzonaphthothiophene (m/z 234), dibenzofuran (m/z 168, m/z 182, m/z 196), fluorene (m/z 166, m/z 180, m/z 194), chrysene (m/z 228, m/z 242, m/z 256), biphenyl (m/z 154, m/z 168, m/z 182), triaromatic sterane
(m/z 231) and benzohopane (m/z 191).
30] desmethyl- and desmethyl/4-methyl steranes
and distribution of desmethyl-([C.
Geochemical application of sterane
and triterpane biomarkers to a description of oils from the Taranaki Basin in New Zealand.
In contrast, the higher-emitting vehicles dearly showed higher proportions of the hopane and sterane
compounds (components of lubricating oils).
Reduction, hydrogenation, and biodegradation are helpful to form sterane
in sedimentary rocks.
are used as the possible indicators for organic maturity in our work.
The m/z 217 and m/z 191 mass chromatograms showing the sterane
and triterpane distributions in the oil shale samples from different areas are presented in Figs.
An abundance of C27 steranes
relative to C29 counterparts, indicates the likelihood of an algal based origin with the analysis of the aromatic fraction indicating a very high level of thermal maturity (>1% RO).
Yet the samples also held small quantities of hopanes, a class of organic chemicals produced by cyanobacteria and some other bacteria, as well as steranes
, which are produced only by eukaryotes.
16] bicyclic alkanes extensive removed 6 smaller steranes
removed, larger steranes
heavy altered, 25-norhopanes formed 7 all steranes
removed, 25-norhopanes more heavy abundant 8 hopanes altered very heavy 9 hopanes removed, disteranes altered, severe
Airborne PM was predominantly (> 99% by particle number) in the fine and ultrafine fractions (Figure 2) and contained a large amount of organic carbon and high concentrations of polycyclic aromatic hydrocarbons, nitrates, hopanes, and steranes
, suggesting that much of the PM was combustion derived and related to traffic sources [see Supplemental Material, Table Si (http://dx.