Zobrazeno 1 - 10
of 208
pro vyhledávání: '"John K VOLKMAN"'
Publikováno v:
Shiyou shiyan dizhi, Vol 45, Iss 5, Pp 963-972 (2023)
As one of the major fractions of petroleum and/or source rock extracts, asphaltene is commonly characte-rized by complicate molecular structures as well as relatively higher molecular weight (MW). The asphaltene occluded biomarkers have been well int
Externí odkaz:
https://doaj.org/article/edd0a79a1faf432189ca6223a9ec72e1
Autor:
Guy C J Abell, Stan S Robert, Dion M F Frampton, John K Volkman, Farhan Rizwi, József Csontos, Levente Bodrossy
Publikováno v:
PLoS ONE, Vol 7, Iss 12, p e51542 (2012)
Advances in microbial ecology research are more often than not limited by the capabilities of available methodologies. Aerobic autotrophic nitrification is one of the most important and well studied microbiological processes in terrestrial and aquati
Externí odkaz:
https://doaj.org/article/000aacd46c8648cebe309d2282fc9118
Autor:
Wenxu Zhou, Xu Zhang, Aoqi Wang, Lin Yang, Qinhua Gan, Liang Yi, Roger E. Summons, John K. Volkman, Yandu Lu
Publikováno v:
Journal of the American Chemical Society. 144:9023-9032
The 4-methyl steranes serve as molecular fossils and are used for studying both eukaryotic evolution and geological history. The occurrence of 4α-methyl steranes in sediments has long been considered evidence of products of partial demethylation med
Autor:
John K. Volkman
Publikováno v:
Elements. 18:115-120
Organic geochemistry continues to make important contributions to our understanding of how the biogeochemistry of our planet and its environment has changed over time and of the role of human impacts today. This article provides a brief overview of t
Autor:
John K. Volkman
Publikováno v:
Papers and Proceedings of the Royal Society of Tasmania. :1-4
In 2018, The Royal Society of Tasmania commenced its celebration of 175 years of service to the people of Tasmania. As the culmination of these celebrations a special plaque was unveiled at the Argyle Street entrance to the Tasmanian Museum and Art G
Algal origin of sponge sterane biomarkers negates the oldest evidence for animals in the rock record
Autor:
Ilya, Bobrovskiy, Janet M, Hope, Benjamin J, Nettersheim, John K, Volkman, Christian, Hallmann, Jochen J, Brocks
Publikováno v:
Nature ecologyevolution. 5(2)
The earliest fossils of animal-like organisms occur in Ediacaran rocks that are approximately 571 million years old. Yet 24-isopropylcholestanes and other C
Autor:
John K. Volkman, Simon N. Ingram, Diane Claridge, Steven J. Rowland, Christopher H. Vane, Charlotte Dunn, Paul A. Sutton, Barbara von der Lühe
Publikováno v:
Natural product research. 35(22)
For nearly 200 years, the only natural source of the alcohol ambrein has been coproliths produced in about 1% of sperm whales and in related jetsam. However, the finding of ambrein in adipocere/faeces of human corpses, led us to hypothesise that ambr
Autor:
John K. Volkman
Publikováno v:
Hydrocarbons, Oils and Lipids: Diversity, Origin, Chemistry and Fate ISBN: 9783319545295
Hydrocarbons, Oils and Lipids: Diversity, Origin, Chemistry and Fate
Hydrocarbons, Oils and Lipids: Diversity, Origin, Chemistry and Fate
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::49b11f36b84c415b0bd0cbd725e3dbd1
https://doi.org/10.1007/978-3-319-90569-3_10
https://doi.org/10.1007/978-3-319-90569-3_10
Publikováno v:
Organic Geochemistry. 112:119-126
Eocene Maoming oil shale was extracted and the precipitated asphaltene was subjected to stepwise pyrolysis carried out in seven temperature steps from 310 °C to 610 °C at 50 °C intervals. The pyrolyzate at 310 °C included n -alkanes and botryococ
Autor:
John K. Volkman, Zhirong Zhang
Publikováno v:
Organic Geochemistry. 104:1-7
Dried biomass of the eustigmatophyte Nannochloropsis oculata was subjected to stepwise pyrolysis at 50 °C intervals from 310 to 610 °C to test the potential of the technique for investigating the algaenan structure of N. oculata and for determining