Journal articles: 'Aliphatic hydrocarbons'

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Doley, Ruby, and Manoj Barthakur. "Biotransformation of aromatic hydrocarbon: Naphthalene to Aliphatic Hydrocarbons through Staphylococcus pasteuri RD2." Annals of Plant Sciences 7, no. 5 (April 30, 2018): 2247. http://dx.doi.org/10.21746/aps.2018.7.5.7.

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Aromatic hydrocarbons like naphthalene are common environmental pollutants of petrochemical waste. Microorganisms have been exploited since long back to clean up such pollutants by converting them in to either non- toxic or less toxic aromatic or aliphatic compounds. A bacterial strain have been isolated from oil sludge of Guwahati Refinery, Assam and was identified as Staphylococcus pasteuri RD2 (NCBI accession number MG680735) through 16srDNA sequence analysis and molecular phylogeny. The bacterial strain transforms Naphthalene, a common hazardous aromatic hydrocarbon found in petrochemical waste, into a number of less hazardous aliphatic hydrocarbons. Detection of compounds such as Decane, Dodecane, tetradecane, Hexadecane, Eicosane, and heptane by GC-MS analysis of naphthalene enrichment culture broth suggested that the bacterial strain was able to transform naphthalene in to different aliphatic hydrocarbons with less toxicity and having chain length of C7 to C20. It has also been depicted a pathway to obtain aliphatic hydrocarbons with higher caloric value from aromatic hydrocarbon waste.

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Díaz-Ramírez, I. J., H. Ramírez-Saad, M. Gutiérrez-Rojas, and E. Favela-Torres. "Biodegradation of Maya crude oil fractions by bacterial strains and a defined mixed culture isolated from Cyperus laxus rhizosphere soil in a contaminated site." Canadian Journal of Microbiology 49, no. 12 (December 1, 2003): 755–61. http://dx.doi.org/10.1139/w03-098.

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Ten bacterial strains were isolated by enrichment culture, using as carbon sources either aliphatics or an aromatic–polar mixture. Oxygen uptake rate was used as a criterion to determine culture transfer timing at each enrichment stage. Biodegradation of aliphatics (10 000 mg L–1) and an aromatic–polar mixture (5000 mg L–1, 2:1) was evaluated for each of the bacterial strains and for a defined culture made up with a standardized mixture of the isolated strains. Degradation of total hydrocarbons (10 000 mg L–1) was also determined for the defined mixed culture. Five bacterial strains were able to degrade more than 50% of the aliphatic fraction. The most extensive biodegradation (74%) was obtained with strain Bs 9A, while strains Ps 2AP and UAM 10AP were able to degrade up to 15% of the aromatic–polar mixture. The defined mixed culture degraded 47% of the aliphatics and 6% of the aromatic–polar mixture. The defined mixed culture was able to degrade about 40% of the aliphatic fraction and 26% of the aromatic fraction when grown in the presence of total hydrocarbons, while these microorganisms did not consume the polar hydrocarbons fraction. The proposed strategy that combines enrichment culture together with oxygen uptake rate allowed the isolation of bacterial strains that are able to degrade specific hydrocarbons fractions at high consumption rates.Key words: biodegradation, defined mixed culture, enrichment culture, hydrocarbon fractions, oxygen uptake.

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Stakėnienė, Rimutė, Kęstutis Jokšas, Rimantė Zinkutė, and Eva Raudonytė-Svirbutavičienė. "Oil pollution and geochemical hydrocarbon origin markers in sediments of the Curonian Lagoon and the Nemunas River Delta." Baltica 32, no. 1 (August 1, 2019): 22–32. http://dx.doi.org/10.5200/baltica.2019.1.3.

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The continuous research on anthropogenized coastal zones determined qualitative and quantitative characteristics of aliphatic hydrocarbons in the Curonian Lagoon and the Nemunas River Delta. The concentration of aliphatic hydrocarbons varied from 9.1 to 187.6 μg g−1 d.w. The Curonian Lagoon could be classified as a slightly contaminated water basin with some moderately polluted areas, while both rivers and Lake Krokų Lanka were found to be slightly contaminated with aliphatic hydrocarbons. The prevailing unresolved complex mixture and geochemical markers suggested the existence of mixed biogenic-anthropogenic aliphatic hydrocarbon sources in the area studied. The biogenic impact was found to be more pronounced in Lake Krokų Lanka, the south-eastern part of the Curonian Lagoon and in the River Minija, while the Nemunas River Avandelta demonstrated the highest loading of anthropogenic hydrocarbons. The same trends were confirmed by the principal component analysis.

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Parinos, C., A. Gogou, I. Bouloubassi, R. Pedrosa-Pàmies, I. Hatzianestis, A. Sànchez-Vidal, G. Rousakis, D. Velaoras, G. Krokos, and V. Lykousis. "Occurrence, sources and transport pathways of natural and anthropogenic hydrocarbons in deep-sea sediments of the Eastern Mediterranean Sea." Biogeosciences Discussions 9, no. 12 (December 13, 2012): 17999–8038. http://dx.doi.org/10.5194/bgd-9-17999-2012.

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Abstract. Surface sediments collected from deep basins (22 stations, 1018–4087 m depth) of the Eastern Mediterranean Sea (EMS) were analyzed for aliphatic, triterpenoid and polycyclic aromatic hydrocarbons (PAHs) as tracers of natural and anthropogenic inputs. Concentrations of total aliphatic hydrocarbons (TAHC), n-alkanes (NA) and the Unresolved Complex Mixture (UCM) of aliphatic hydrocarbons ranged from 1.34 to 49.2 µg g−1, 145 to 4810 ng g−1 and 0.73 to 36.7 µg g−1, respectively, while total PAHs (TPAH25) concentrations ranged from 11.6 to 223 ng g−1. Molecular profiles of aliphatic hydrocarbons and PAHs reflect the contribution of both natural (epicuticular plant waxes) and anthropogenic (degraded petroleum products, unburned fossil fuels and combustion of petroleum, grass, wood and coal) compounds in deep EMS sediments, with hydrocarbon mixtures displaying significant regional variability. Hydrocarbon concentrations correlated significantly with the Total Organic Carbon (TOC) content of sediments, indicating that organic carbon exerts an important control on their transport and fate in the study area, while strong sub-basin and mesoscale variability of water masses also impact their regional characteristics. Major findings of this study support that deep basins/canyons of the EMS could act as traps of both natural and anthropogenic hydrocarbons.

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April, T. M., J. M. Foght, and R. S. Currah. "Hydrocarbon-degrading filamentous fungi isolated from flare pit soils in northern and western Canada." Canadian Journal of Microbiology 46, no. 1 (December 17, 1999): 38–49. http://dx.doi.org/10.1139/w99-117.

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Sixty-four species of filamentous fungi from five flare pits in northern and western Canada were tested for their ability to degrade crude oil using gas chromatographic analysis of residual hydrocarbons following incubation. Nine isolates were tested further using radiorespirometry to determine the extent of mineralization of model radiolabelled aliphatic and aromatic hydrocarbons dissolved in crude oil. Hydrocarbon biodegradation capability was observed in species representing six orders of the Ascomycota. Gas chromatography indicated that species capable of hydrocarbon degradation attacked compounds within the aliphatic fraction of crude oil, n-C12- n-C26; degradation of compounds within the aromatic fraction was not observed. Radiorespirometry, using n-[1-14C]hexadecane and [9-14C]phenanthrene, confirmed the gas chromatographic results and verified that aliphatic compounds were being mineralized, not simply transformed to intermediate metabolites. This study shows that filamentous fungi may play an integral role in the in situ biodegradation of aliphatic pollutants in flare pit soils.Key words: bioremediation, filamentous fungi, flare pits, hydrocarbon degradation, petroleum.

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Kotova, V. E., Yu А. Andreev, О. А. Mikhaylenko, and I. А. Ryazantseva. "ASSESSMENT OF PETROLEUM COMPONENT CONTAMINATION OF WATER IN THE TEMERNIK RIVER AND ITS INFLUENCE ON THE DON RIVER." Ecology. Economy. Informatics.System analysis and mathematical modeling of ecological and economic systems 1, no. 6 (2021): 112–17. http://dx.doi.org/10.23885/2500-395x-2021-1-6-112-117.

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Here, we report the results of petroleum component contamination assessment of the Temernik river and the Don river. Our aim was to study the hydrocarbon group content of petroleum components in the river water. Thus, we determined the mass concentrations of chemical oxygen demand, petroleum components, and aliphatic and polycyclic aromatic hydrocarbons. In the Temernik river, the concentrations of chemical oxygen demand, petroleum components, sum of aliphatic and polycyclic aromatic hydrocarbons were 21.4–34.4 mg/L, 0.14–6.0 mg/L, 10–18 μg/L, and 0.17–2.9 μg/L, respectively. The concentrations of chemical oxygen demand, petroleum components, and benzo[a]pyrene exceeded the maximum permissible concentration by 1.4–2.3, 2.8-120, and 1.3–5.8 times, respectively. In the Don river, the concentrations of chemical oxygen demand, petroleum components, sum of aliphatic and polycyclic aromatic hydrocarbons were 18.7-29.5 mg/L, 0.08- 0.16 mg/L, 8.2-12 μg/L, and 0.03-0.13 μg/L, respectively. The Severnoe reservoir was the less contaminated part of the river. The Temernik river estuary was the most contaminated part of the river. The pollutant concentrations increased in the Don River downstream of the Temernik river estuary. Therefore, the Temernik river influences on the Don river contamination. The chemical oxygen demand, petroleum components, and polycyclic aromatic hydrocarbons had the close distribution of concentrations in the rivers. However, the aliphatic hydrocarbon concentration changed in another way. The results of the study showed that the hydrocarbon groups of petroleum components can have different sources.

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Sloan, G. C. "Spitzer spectroscopy of unusual hydrocarbons in cool radiative environments." Proceedings of the International Astronomical Union 4, S251 (February 2008): 191–94. http://dx.doi.org/10.1017/s1743921308021534.

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AbstractThe Spitzer Space Telescope has discovered several objects with unusual spectra, where the emission features from polycyclic aromatic hydrocarbons (PAHs) are shifted to longer wavelengths than normally observed. Previously, only two of these class C PAH spectra had been identified. The new and larger sample reveals that PAHs emit at longer wavelengths when processed by cooler radiation fields. Limited laboratory data show that samples with mixtures of aromatic and aliphatic hydrocarbons produce emission features at longer wavelengths than purely aromatic samples. The aliphatic bonds are more fragile and would only survive in cooler radiation fields. In harsher radiation fields, the aliphatics attached to the aromatic hydrocarbons are destroyed.

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Pattanayak, Rojalin, Geetanjali Mishra, Chandan Singh Chanotiya, Prasant Kumar Rout, Chandra Sekhar Mohanty, and Omkar. "Semiochemical profile of four aphidophagous Indian Coccinellidae (Coleoptera)." Canadian Entomologist 148, no. 2 (August 3, 2015): 171–86. http://dx.doi.org/10.4039/tce.2015.45.

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AbstractThe emitted aliphatic hydrocarbon profile of four Indian Coccinellidae (Coleoptera), Coccinella septempunctata (Linnaeus) (C7), Coccinella transversalis Fabricius (Ct), Menochilus sexmaculatus (Fabricius) (Ms), and Propylea dissecta (Mulsant) (Pd) has been investigated by simple solvent-less headspace solid-phase microextraction (HS-SPME) technique coupled with gas chromatography and mass spectroscopy (GC-MS). Identified volatile and non-volatile compounds were confirmed by running corresponding standards and comparing with the National Institute of Standards and Technology library. Among the 56 identified aliphatic hydrocarbons, saturated aliphatic hydrocarbons were more in number than unsaturated ones. Among saturated hydrocarbons, methyl branched hydrocarbons were more in number in C7 and Ct than Ms and Pd. Menochilus sexmaculatus and Pd had higher percentages of unsaturated hydrocarbons than C7 and Ct. Among branched chain-hydrocarbons, mono-methylated saturated hydrocarbons were more in number than dimethylated saturated hydrocarbons. Further analysis of the semiochemical profile revealed a closeness between C7 and Ct, and between Ms and Pd. Quantitative analysis revealed that straight chain hydrocarbons form separate clusters to branched chain methylated hydrocarbons. This is the first attempt to identify the semiochemical profile of some Indian coccinellids using the headspace solid phase micro-extraction technique coupled with the gas chromatography-mass spectrometry technique. This report will be helpful for various chemotaxonomic studies of the species in the future.

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9

Gómez-Coca, R. B., R. Cert, M. C. Pérez-Camino, and W. Moreda. "Determination of saturated aliphatic hydrocarbons in vegetable oils." Grasas y Aceites 67, no. 2 (April 8, 2016): e127. http://dx.doi.org/10.3989/gya.0627152.

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10

Parinos, C., A. Gogou, I. Bouloubassi, R. Pedrosa-Pàmies, I. Hatzianestis, A. Sanchez-Vidal, G. Rousakis, D. Velaoras, G. Krokos, and V. Lykousis. "Occurrence, sources and transport pathways of natural and anthropogenic hydrocarbons in deep-sea sediments of the eastern Mediterranean Sea." Biogeosciences 10, no. 9 (September 24, 2013): 6069–89. http://dx.doi.org/10.5194/bg-10-6069-2013.

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Abstract. Surface sediments collected from deep basins (1018–4087 m depth) of the eastern Mediterranean Sea (Ionian Sea, southern Aegean Sea and northwestern Levantine Sea) were analyzed for aliphatic and polycyclic aromatic hydrocarbons as tracers of natural and anthropogenic inputs. Concentrations of total aliphatic hydrocarbons, n-alkanes and the unresolved complex mixture (UCM) of aliphatic hydrocarbons varied significantly, ranging from 1.34 to 49.2 μg g−1, 145 to 4810 ng g−1 and 0.73 to 36.7 μg g−1, respectively, while concentrations of total polycyclic aromatic hydrocarbons (PAHs) ranged between 11.6 and 223 ng g−1. Molecular profiles of determined hydrocarbons reflect a mixed contribution from both natural and anthropogenic sources in deep-sea sediments of the eastern Mediterranean Sea, i.e., terrestrial plant waxes, degraded petroleum products, unburned fossil fuels and combustion of grass, wood and coal. Hydrocarbon mixtures display significant variability amongst sub-regions, reflecting differences in the relative importance of inputs from various sources and phase associations/transport pathways of individual hydrocarbons that impact on their overall distribution and fate. Hydrocarbon concentrations correlated significantly with the organic carbon content of sediments, indicating that the latter exerts an important control on their transport and ultimate accumulation in deep basins. Additionally, water masses' circulation characteristics also seem to influence the regional features and distribution patterns of hydrocarbons. Our findings highlight the role of deep basins/canyons as repositories of both natural and anthropogenic chemical species.

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Milan, Michela, Massimo Bietti, and Miquel Costas. "Enantioselective aliphatic C–H bond oxidation catalyzed by bioinspired complexes." Chemical Communications 54, no. 69 (2018): 9559–70. http://dx.doi.org/10.1039/c8cc03165g.

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Enantioselective aliphatic C–H bond oxidation simultaneously installs functionality and chirality into hydrocarbon units, converting in a single step readily available, inexpensive and typically inert hydrocarbons into precious building blocks for organic synthesis.

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Firrincieli, Andrea, Andrea Negroni, Giulio Zanaroli, and Martina Cappelletti. "Unraveling the Metabolic Potential of Asgardarchaeota in a Sediment from the Mediterranean Hydrocarbon-Contaminated Water Basin Mar Piccolo (Taranto, Italy)." Microorganisms 9, no. 4 (April 16, 2021): 859. http://dx.doi.org/10.3390/microorganisms9040859.

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Increasing number of metagenome sequencing studies have proposed a central metabolic role of still understudied Archaeal members in natural and artificial ecosystems. However, their role in hydrocarbon cycling, particularly in the anaerobic biodegradation of aliphatic and aromatic hydrocarbons, is still mostly unknown in both marine and terrestrial environments. In this work, we focused our study on the metagenomic characterization of the archaeal community inhabiting the Mar Piccolo (Taranto, Italy, central Mediterranean) sediments heavily contaminated by petroleum hydrocarbons and polychlorinated biphenyls (PCB). Among metagenomic bins reconstructed from Mar Piccolo microbial community, we have identified members of the Asgardarchaeota superphylum that has been recently proposed to play a central role in hydrocarbon cycling in natural ecosystems under anoxic conditions. In particular, we found members affiliated with Thorarchaeota, Heimdallarchaeota, and Lokiarchaeota phyla and analyzed their genomic potential involved in central metabolism and hydrocarbon biodegradation. Metabolic prediction based on metagenomic analysis identified the malonyl-CoA and benzoyl-CoA routes as the pathways involved in aliphatic and aromatic biodegradation in these Asgardarchaeota members. This is the first study to give insight into the archaeal community functionality and connection to hydrocarbon degradation in marine sediment historically contaminated by hydrocarbons.

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Lee, Nahyeon, Junghee Joo, Kun-Yi Andrew Lin, and Jechan Lee. "Waste-to-Fuels: Pyrolysis of Low-Density Polyethylene Waste in the Presence of H-ZSM-11." Polymers 13, no. 8 (April 7, 2021): 1198. http://dx.doi.org/10.3390/polym13081198.

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Herein, the pyrolysis of low-density polyethylene (LDPE) scrap in the presence of a H-ZSM-11 zeolite was conducted as an effort to valorize plastic waste to fuel-range chemicals. The LDPE-derived pyrolytic gas was composed of low-molecular-weight aliphatic hydrocarbons (e.g., methane, ethane, propane, ethylene, and propylene) and hydrogen. An increase in pyrolysis temperature led to increasing the gaseous hydrocarbon yields for the pyrolysis of LDPE. Using the H-ZSM-11 catalyst in the pyrolysis of LDPE greatly enhanced the content of propylene in the pyrolytic gas because of promoted dehydrogenation of propane formed during the pyrolysis. Apart from the light aliphatic hydrocarbons, jet fuel-, diesel-, and motor oil-range hydrocarbons were found in the pyrolytic liquid for the non-catalytic and catalytic pyrolysis. The change in pyrolysis temperature for the catalytic pyrolysis affected the hydrocarbon compositions of the pyrolytic liquid more materially than for the non-catalytic pyrolysis. This study experimentally showed that H-ZSM-11 can be effective at producing fuel-range hydrocarbons from LDPE waste through pyrolysis. The results would contribute to the development of waste valorization process via plastic upcycling.

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Pandolfo, Emiliana, Anna Barra Caracciolo, and Ludovica Rolando. "Recent Advances in Bacterial Degradation of Hydrocarbons." Water 15, no. 2 (January 16, 2023): 375. http://dx.doi.org/10.3390/w15020375.

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Hydrocarbons occur in fossil fuels such as crude oil and consist mainly of hydrogen and carbon. Although they are natural chemicals, crude oil refining results in commercial products with new physico-chemical properties, which can increase their complexity and toxicity, and hamper their degradation. The presence of biodiverse natural microbial communities is a prerequisite for an effective homeostatic response to the various hydrocarbons, that contaminate ecosystems. However, their removal depends on the compartment contaminated (water, sediment, soil), their molecular weight, and their toxicity not hampering microbial activity. This paper reports different bacterial species involved in the biodegradation of aliphatic and aromatic hydrocarbons. Hydrocarbon contamination is generally due to the co-presence of a mixture of these chemicals, and their removal from the environment cannot rely on only a single species but generally requires bacterial consortia. Versatile bacterial metabolism relies on specific genes encoding the key enzymes involved in the peripheral metabolic and central metabolic pathways for degrading aliphatic and polycyclic aromatic hydrocarbons. Although microbial metabolism can have the potential for natural attenuation of these contaminants, hydrocarbon bioremediation, through biostimulation (e.g., use of surfactants, plants, earthworms, and nanoparticles) and bioaugmentation, can be a valid tool for removing them from actually contaminated soil, freshwater, groundwater, and seawater.

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Payne, J. F., L. L. Fancey, J. Hellou, M. J. King, and G. L. Fletcher. "Aliphatic hydrocarbons in sediments: a chronic toxicity study with winter flounder (Pleuronectes americanus) exposed to oil well drill cuttings." Canadian Journal of Fisheries and Aquatic Sciences 52, no. 12 (December 1, 1995): 2724–35. http://dx.doi.org/10.1139/f95-861.

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Most studies on the chronic toxicity of hydrocarbons have focused on the polycyclic aromatic component; however, information is also required on the chronic toxicity of other classes of hydrocarbons. This need has been brought to the forefront by the controversy about the use of aliphatic hydrocarbon-based drilling fluids at petroleum development sites in the marine environment. Dose–response relationships were studied for a variety of indices in a chronic toxicity study with winter flounder (Pleuronectes americanus) exposed to sediments contaminated with drill cuttings enriched in hydrocarbons. The indices investigated were biologically meaningful and included organ and body condition indices, muscle and liver energy reserves, mixed-function oxygenase detoxification enzymes, blood parameters, and liver and gill histopathology. There was no evidence of dose–response relationships and most indices remained unaffected even at the highest exposure level. The study supports the hypothesis that the aliphatic component of complex hydrocarbon mixtures is relatively nontoxic, and it will be of particular interest for evaluating the scope of environmental risks associated with the use of oil-base drilling fluids in the marine environment.

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Feitkenhauer, H., and H. Märkl. "Biodegradation of aliphatic and aromatic hydrocarbons at high temperatures." Water Science and Technology 47, no. 10 (May 1, 2003): 123–30. http://dx.doi.org/10.2166/wst.2003.0555.

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In this paper, the high temperature (65-75°C) biodegradation of aliphatic and aromatic hydrocarbons is investigated and kinetic parameters are derived. The shift of the physico-chemical system properties with rising temperature will be discussed in detail. For example, the solubility of naphthalene is increased by a factor of about ten if the temperature is increased from 20 to 75°C. This effect is essential to increase the bioavailability of sparingly soluble hydrocarbons. It is also demonstrated in experiments that very high oxygen transfer rates can be obtained at high temperatures in the presence of hydrocarbons. It is shown that efficient phenol biodegradation is essential for high temperature hydrocarbon degradation because some microorganisms tend to transform phenols into polyphenols which are very inhibitory for microbial growth. A defined mixed culture adapted to phenol converted more than 90% of a mixture of phenol, hexadecane and pyrene and a very high maximal growth rate of 0.19 h−1 was determined. A yield coefficient YX/S of about 0.8 g (biomass)/g (hydrocarbons) was calculated in this experiment. In a separate experiment the influence of the hydrocarbon droplet size on the biodegradation is investigated at 70°C using a newly isolated Thermus sp. In this case, the growth on a hexadecane/pyrene mixture was described by a model based on the Monod equation and the corresponding kinetic parameters are derived. A mixed culture was used for the bioremediation of soil in a slurry reactor. The initial contamination of 11 g/kg was lowered to about 2 g in a reactor inoculated by an immobilized culture of extreme thermophilic microorganisms, while 9 g/kg remained in a sterile control.

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Schuhmann, M., K. Altwegg, H. Balsiger, J. J. Berthelier, J. De Keyser, B. Fiethe, S. A. Fuselier, et al. "Aliphatic and aromatic hydrocarbons in comet 67P/Churyumov-Gerasimenko seen by ROSINA." Astronomy & Astrophysics 630 (September 20, 2019): A31. http://dx.doi.org/10.1051/0004-6361/201834666.

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Context. Unlike all previous cometary space missions, the Rosetta spacecraft accompanied its target, comet 67P/Churyumov-Gerasimenko, for more than two years on its way around the Sun. Thereby, an unexpected diversity and complexity of the chemical composition was revealed. Aims. Our first step of decrypting the exact chemical composition of the gaseous phase is the identifying and quantifying the bulk composition of the pure aromatic and aliphatic hydrocarbons. Methods. For this study, data from ROSINA–Double Focusing Mass Spectrometer (DFMS) onboard the Rosetta spacecraft and the laboratory twin model were used. A joint campaign of laboratory calibration measurements and space data analysis was performed to derive the hydrocarbon bulk composition for the post-inbound equinox period at 1.52 AU in May 2015. Furthermore, several other mission phases were investigated to determine the dependencies of season, location, and heliocentric distance on the relative abundances of hydrocarbons. Results. It is shown that the bulk composition of the gaseous phase includes a high number of aliphatic compounds such as methane, ethane, and propane, as well as the aromatic compounds benzene and toluene. Butane and pentane were successfully identified in measurements at closer distance to the comet in May 2016. Furthermore, the presence of hexane and heptane in the coma is confirmed on rare occasions during the mission. Their presence in DFMS space data appears to be linked to days or periods of high dust activity. In addition to the saturated aliphatic and aromatic compounds, a high number of remaining unsaturated species is present, which cannot be explained by fragmentation of saturated species or contribution from other organic molecules in addition to pure hydrocarbons. This indicates the existence of unsaturated aliphatic and aromatic hydrocarbon molecules in the coma of comet 67P.

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Acquah, F., A. T. Kuhn, and C. J. Mortimer. "The electrochlorination of aliphatic hydrocarbons." Journal of Applied Chemistry and Biotechnology 22, no. 11 (April 25, 2007): 1195–200. http://dx.doi.org/10.1002/jctb.5020221107.

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Landry, Jean-François, and Serge Langlois. "Acute Exposure to Aliphatic Hydrocarbons." Archives of Internal Medicine 158, no. 16 (September 14, 1998): 1821. http://dx.doi.org/10.1001/archinte.158.16.1821.

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Asaftei, Iuliean V., Ion Sandu, Nicolae Bilba, Neculai Catalin Lungu, Maria Ignat, and Elvira Mahu. "Oligo-Aromatization of Light Hydrocarbons from Petroleum Refining Processes Over ZnO/MFI Microporous Material." Revista de Chimie 71, no. 2 (March 3, 2020): 403–12. http://dx.doi.org/10.37358/rc.20.2.7943.

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The conversion of light hydrocarbons resulted as by-product of petroleum refining (mixtures of (n + i) butanes, 52.28 � 63.20 vol.%, (1-, cis-, trans-, 2-) butenes, 28.64 � 36.43 vol.% and propane � propylene, 4.79 � 14.64 vol.%) over bifunctional 5% ZnO/HZSM-5 co-catalyst in a fixed-bed stainless-steel reactor (Twin Reactor System Naky) at 450�C, 4 atm. total pressure and at a space velocity (WHSV) of 1 h-1 have been investigated. The results indicate that the selectivity to light aromatics � benzene, toluene and xylenes (BTX) � and to both the gaseous C1, C2 - C4 hydrocarbons and liquid (i + n) C5 � C10 aliphatic hydrocarbons depends on the time on stream of the process. This is a result of coke deposition (polyunsaturated compounds) and catalyst deactivation. The aromatics BTX represent 59-60 wt% in the liquid product during the first 24-36 hours time-on-stream and only 20-30 wt% after 40 hours of reaction when the aliphatic hydrocarbon C5 � C10 (mostly iso) and ]C10 (denoted �oligo�) reach to 70 � 80 wt%. The aromatic products were principally toluene, xylenes and benzene, theirs concentration varying with the time on stream of the process. The initial aromatization process described as dehydrocyclodimerization of alkanes and alkenes, principally to aromatics BTX and molecular hydrogen is accompanied by an oligomerization, isomerisation, cracking and alkylation process to form finally in the liquid product an excessively mixture of iso- and normal- C5 � C10 aliphatic hydrocarbons and ] C10.

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Darılmaz, Enis. "Investigation of aliphatic hydrocarbons in red mullet (Mullus barbatus) and European hake (Merluccius merluccius) fish caught from the Edremit Bay (Western Turkey)." Ege Journal of Fisheries and Aquatic Sciences 38, no. 1 (March 15, 2021): 1–10. http://dx.doi.org/10.12714/egejfas.38.1.01.

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In this study, aliphatic hydrocarbon levels were investigated in red mullet and european hake fish caught by trawler from Edremit Bay (Western Aegean, Turkey) in spring and autumn 2015. For this purpose, trawling was carried out from 3 different regions of the Edremit Bay in both seasons. As a result of the analyzes, total aliphatic hydrocarbon (TAH) levels in red mullet were found to be higher than that of european hake. TAH concentrations found for red mullet were in the range of 456-2090 ng/g, while it was found in the range of 61-746 ng/g for european hake. In general, TAH concentrations in red mullet were higher than that of european hake for both seasons. In addition, EOM amounts were found higher in red mullet like TAH. According to correlation, cluster and primary component analysis results, it was observed that the compounds affecting TAH levels in red mullet are C11 and C12 aliphatic hydrocarbon compounds, while european hake have C15, C17 and Pristane compounds. These results indicate that the source of aliphatic hydrocarbons in Edremit Bay fish is biogenic in european hake samples, although not exact, it may be petrogenic in red mullet samples.

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Shi, Zhen Jing, Meng Xiang Fang, Qing Hui Wang, and Zhong Yang Luo. "Studies on Rapid Pyrolysis Characteristics of Huainan Coal." Applied Mechanics and Materials 316-317 (April 2013): 32–35. http://dx.doi.org/10.4028/www.scientific.net/amm.316-317.32.

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This paper aims to investigate the rapid pyrolysis characteristics of Huainan coal using a tube furnace. Influence of temperature on yields and compounds of tar and char are tested. The result shows that aliphatic chains break gradually with increasing pyrolysis temperature. This leads an increase in aromaticity. Maximum tar yields were obtained at about 550°C, the char yields decreased and the gas yields increased with the pyrolysis temperature. The tar was isolated to aliphatic hydrocarbon aromatic hydrocarbon, non hydrocarbon and asphaltene, and characterized by chromatography-mass spectrometry (GC/MS). The main content of tar include normal alkanes from C16-C30, two-,three- and four-ring aromatic hydrocarbons and alkyl-substituted hydroaromatic derivatives of polycyclic, phenols, indoles, quinines esters and others compounds.

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Habib, Syahir, Wan Lutfi Wan Johari, Mohd Yunus Shukor, and Nur Adeela Yasid. "Screening of hydrocarbon-degrading bacterial isolates using the redox application of 2,6-DCPIP." Bioremediation Science and Technology Research 5, no. 2 (December 31, 2017): 13–16. http://dx.doi.org/10.54987/bstr.v5i2.358.

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Petroleum hydrocarbons remain as the major contaminants that could be found across the world. Remediation approach through the utilisation of microbes as the bioremediation means is widely recognised due to their outstanding values. As a result, scientific reports on the isolation and identification of new hydrocarbon-degrading strains were on the rise. Colourimetric-based assays are one of the fastest methods to identify the capability of hydrocarbon-degrading strains in both qualitative and quantitative assessment. In this study, the hydrocarbon-degrading potential of nine bacterial isolates was observed via 2,6-dichlorophenolindophenol (DCPIP) test. Two potent diesel-utilising isolates show a distinctive tendency to utilise aromatic (ADL15) and aliphatic (ADL36) hydrocarbons. Both isolates prove to be a good candidate for bioremediation of wide range of petroleum hydrocarbon components.

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Rocher, V., S. Azimi, R. Moilleron, and G. Chebbo. "Biofilm in combined sewers: wet weather pollution source and/or dry weather pollution indicator?" Water Science and Technology 47, no. 4 (February 1, 2003): 35–43. http://dx.doi.org/10.2166/wst.2003.0215.

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In a sewer trunk, three kinds of deposit, acting as potential wet weather sources, can be found: the biofilm, the organic layer and the gross bed sediment. This research program, on the “Le Marais” catchment (Paris, France), focused on the biofilm. The objectives were to describe, using a Transmission Electronic Microscope, the architecture of the sewer biofilm and to investigate the contents and the distributions of aliphatic and aromatic hydrocarbons in biofilm. The electron micrographs illustrated a uniform film of bacteria totally covering the surface of a thick organic matrix. A large cohesion of the cell layer and organic matrix complex, due to exopolysaccharides, was noticed. Hence, the hydrocarbon contents were measured not only in the biofilm itself, but in this complex. Our results showed that almost all hydrocarbons were stored in the gross bed sediment and the organic layer and, consequently, the biofilm was not an important potential source of wet weather pollution. Comparison between the hydrocarbon distributions in the biofilm and in the other deposits indicated that the biofilm could be used as an indicator of the aliphatic hydrocarbon pollution in the organic layer.

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Syed, Khajamohiddin, Aleksey Porollo, Ying Wai Lam, Paul E. Grimmett, and Jagjit S. Yadav. "CYP63A2, a Catalytically Versatile Fungal P450 Monooxygenase Capable of Oxidizing Higher-Molecular-Weight Polycyclic Aromatic Hydrocarbons, Alkylphenols, and Alkanes." Applied and Environmental Microbiology 79, no. 8 (February 15, 2013): 2692–702. http://dx.doi.org/10.1128/aem.03767-12.

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ABSTRACTCytochrome P450 monooxygenases (P450s) are known to oxidize hydrocarbons, albeit with limited substrate specificity across classes of these compounds. Here we report a P450 monooxygenase (CYP63A2) from the model ligninolytic white rot fungusPhanerochaete chrysosporiumthat was found to possess a broad oxidizing capability toward structurally diverse hydrocarbons belonging to mutagenic/carcinogenic fused-ring higher-molecular-weight polycyclic aromatic hydrocarbons (HMW-PAHs), endocrine-disrupting long-chain alkylphenols (APs), and crude oil aliphatic hydrocarbonn-alkanes. A homology-based three-dimensional (3D) model revealed the presence of an extraordinarily large active-site cavity in CYP63A2 compared to the mammalian PAH-oxidizing (CYP3A4, CYP1A2, and CYP1B1) and bacterial aliphatic-hydrocarbon-oxidizing (CYP101D and CYP102A1) P450s. This structural feature in conjunction with ligand docking simulations suggested potential versatility of the enzyme. Experimental characterization using recombinantly expressed CYP63A2 revealed its ability to oxidize HMW-PAHs of various ring sizes, including 4 rings (pyrene and fluoranthene), 5 rings [benzo(a)pyrene], and 6 rings [benzo(ghi)perylene], with the highest enzymatic activity being toward the 5-ring PAH followed by the 4-ring and 6-ring PAHs, in that order. Recombinant CYP63A2 activity yielded monohydroxylated PAH metabolites. The enzyme was found to also act as an alkane ω-hydroxylase that oxidizedn-alkanes with various chain lengths (C9to C12and C15to C19), as well as alkyl side chains (C3to C9) in alkylphenols (APs). CYP63A2 showed preferential oxidation of long-chain APs and alkanes. To our knowledge, this is the first P450 identified from any of the biological kingdoms that possesses such broad substrate specificity toward structurally diverse xenobiotics (PAHs, APs, and alkanes), making it a potent enzyme biocatalyst candidate to handle mixed pollution (e.g., crude oil spills).

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Rosik-Dulewska, Czesława, Teresa Krzyśko-Łupicka, Tomasz Ciesielczuk, and Łukasz Kręcidło. "Hydrogen peroxide as a biodegradation stimulator in remediation processes of soils heavily contaminated with petrochemicals." Polish Journal of Chemical Technology 17, no. 2 (June 1, 2015): 17–22. http://dx.doi.org/10.1515/pjct-2015-0023.

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Abstract The soil contaminated with petroleum products must be excluded from the crops and treated to reclamation processes. Natural processes of decomposition of hydrocarbon compounds go very slow, so it is necessary to use bioaugumentation or stimulation in order to accelerate the return of the soil to high culture. In this study the effect of hydrogen peroxide on the process of cleaning soil strongly contaminated with pertochemicals was investigated. For this purpose, a pot experiment lasting 60 days was carried. The dynamics of changes in the population of filamentous fungi, yeasts and bacteria were examined and also content of aliphatic hydrocarbons (n-alkanes), monoaromatic and polycyclic aromatic hydrocarbons (PAHs). Experimental use of hydrogen peroxide in the process of biodegradation of petroleum compounds assisted in the analyzed soil led to an increase of the number of grampositive bacteria during the test. Stimulation of oil products biodegradation by hydrogen peroxide also increased by 35% decomposition efficiency of aliphatic hydrocarbons (C8-C40) and about 50% PAH’s in comparison to control samples without hydrogen peroxide. There was no influence of hydrogen peroxide on the content of monoaromatic hydrocarbons (BTEX) with respect to controls, although in the end of experiment, the total concentration decreased by about 50% compared to the initial content.

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Shoieb, Monera Adam, Haylay Tsegab Gebretsadik, Syed Muhammad Ibad, and Omeid Rahmani. "Depositional Environment and Hydrocarbon Distribution in the Silurian–Devonian Black Shales of Western Peninsular Malaysia Using Spectroscopic Characterization." Minerals 12, no. 12 (November 24, 2022): 1501. http://dx.doi.org/10.3390/min12121501.

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The present study aimed to evaluate the hydrocarbon functional groups, aromaticity degree, and depositional environment in the Silurian–Devonian Kroh black shales of western peninsular Malaysia. Fourier transform infrared spectroscopy (FTIR) was applied to measure the hydrocarbon functional groups in the sedimentary succession and associated organic matter of the black shale samples. The results showed that aromatic C=C stretching, aromatic C-H out-of-plane, aromatic C-H in-plane, and aliphatic =C–H bending are the major hydrocarbon functional groups in the Kroh shales. Also, ultraviolet-visible spectroscopy (UV-Vis) was used to evaluate the type of humic substance and analyze the sample extract ratios of E4/E6. It was revealed that the methanol-treated Kroh shale samples ranged from 0.00048 to 0.12 for E4 and 0.0040 to 0.99 for E6. The lower E4/E6 ratio (> 5) indicates the dominance of humic acid over fulvic acid in the Kroh shales. The Kroh shale samples' total organic carbon content (TOC) ranges from 0.33 to 8.5 wt.%, analyzed by a multi-N/C 3100 TOC/TNb analyzer. The comparison study revealed that the TOC content of the Kroh shale has close obtainable values for the Montney shales of Canada. Furthermore, both hydrocarbon functional groups from FTIR, and the E4/E6 ratio from UV-Vis show no correlation with TOC content. It is revealed that humic acid, aromatic, and aliphatic hydrocarbons are not the controlling factors of the enrichment of organic matter in the Kroh shales. Conversely, a positive correlation between aliphatic and aromatic hydrocarbons in the Kroh shales indicated that organic matter is thermally overmatured. The presence of humic acid and enrichment of aromatic hydrocarbons in the Kroh shales demonstrated that the organic matter in these shales contains plant-derived hydrophilic minerals, i.e., terrestrial in origin. These findings may provide clues on the depositional and thermal maturation of organic matter for the exploration efforts into the pre-Tertiary sedimentary successions of the peninsular.

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Venturini, Natalia, Luiz Roberto Tommasi, Márcia C. Bícego, and César C. Martins. "Characterization of the benthic environment of a coastal area adjacent to an oil refinery, Todos os Santos Bay (NE-Brazil)." Brazilian Journal of Oceanography 52, no. 2 (June 2004): 123–34. http://dx.doi.org/10.1590/s1679-87592004000200004.

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In order to determine the sedimentological and physico-chemical characteristics of the benthic environment and also the level, distribution and probable sources of aliphatic and polycyclic aromatic hydrocarbons, sediment samples were collected at 28 stations in the northeast portion of Todos os Santos Bay. The centre and the east region of the study area showed characteristics of depositional environments with the predominance of silt and clay and high percentages of TOC, nitrogen and sulphur. The molar C/N ratios varied between 8.8 and 27.6 indicating a mixed origin of organic matter with variable marine and continental contributions. Total aliphatic hydrocarbon concentrations ranged between 1.56 and 246.91 µg.g-1 dry weight, corresponding the high concentrations to the stations situated in the centre and in the east region of the study area. The UCM represented between 60 and 96% of the total aliphatic hydrocarbons, indicating a high degree of anthropogenic contribution and the presence of petroleum degraded residues. Total PAH concentrations varied from 8 to 4163 ng.g-1 dry weight. The highest total PAH concentration was recorded at station 5 situated adjacent to the oil refinery.

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29

Lindley, Nicholas D. "Bioconversion and biodegradation of aliphatic hydrocarbons." Canadian Journal of Botany 73, S1 (December 31, 1995): 1034–42. http://dx.doi.org/10.1139/b95-354.

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Aliphatic hydrocarbons represent a substantial energy reserve but also constitute a useful feedstock for the biotechnological production of various alkane-derived commodity chemicals. In addition, the biodegradation of aliphatic hydrocarbons continues to pose problems for fuel stocks with associated corrosion and eventual motor filter blocking. A relatively high number of yeasts and filamentous fungi have been described that degrade n-alkanes, but relatively few have received thorough investigation. Early work exploiting hydrocarbons as a potential substrate for unicellular protein production, though never commercially successful, enabled high-performance fermentation strategies to be developed that overcame many of the inherent problems caused by the use of high energy content insoluble liquid substrates. The biochemical pathways and physiological characteristics have been sufficiently established, as have the subcellular localization of the alkane-specific pathways, though many of the regulatory phenomena remain obscure. Currently, interest lies in the exploitation of such species, or their enzymes, in bioconversion processes and the unicellular yeasts, whose amenability to rational genetic engineering strategies exceeds that of filamentous species, are currently attracting renewed research interest. In view of this, the existing knowledge and potential for alkane-based biotechnology will be reviewed. Key words: alkane metabolism, bioconversion, biotechnology, aliphatic hydrocarbons, yeasts, filamentous fungi.

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Kemp, Jesse M., Lerin R. Luckett-Chastain, Kaitlin N. Calhoun, Benjamin Frempah, Tayler R. Schartz, Linda E. Harty, Philip M. Kemp, and Randle M. Gallucci. "Evaluation of skin irritation following weathered crude oil exposure in two mouse strains." Toxicology and Industrial Health 36, no. 10 (August 18, 2020): 788–99. http://dx.doi.org/10.1177/0748233720944354.

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Petroleum crude oil spills are common and vary in size and scope. Spill response workers throughout the course of remediation are exposed to so-called weathered oil and are known to report diverse health effects, including contact dermatitis. A murine model of repeated exposure to weathered marine crude oil was employed utilizing two strains of mice, C57BL/6 and BALB/c, to investigate the pathology of this irritant and identify the principal hydrocarbon components deposited in skin. Histopathology demonstrated clear signs of irritation in oil-exposed skin from both mouse strains, characterized by prominent epidermal hyperplasia (acanthosis). BALB/c mice exposed to oil demonstrated more pronounced irritation compared with C57BL/6 mice, which was characterized by increased acanthosis as well as increased inflammatory cytokine/chemokine protein expression of IL-1β, IL-6, CXCL10, CCL2, CCL3, CCL4, and CCL11. A gas chromatography/mass spectrometry method was developed for the identification and quantification of 42 aliphatic and EPA priority aromatic hydrocarbons from full thickness skin samples of C57BL/6 and BALB/c mice exposed to oil samples. Aromatic hydrocarbons were not detected in skin; however, aliphatic hydrocarbons in skin tended to accumulate with carbon numbers greater than C16. These preliminary data and observations suggest that weathered crude oil is a skin irritant and this may be related to specific hydrocarbon components, although immune phenotype appears to impact skin response as well.

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Purohit, V., and R. A. Orzel. "Polypropylene: A Literature Review of the Thermal Decomposition Products and Toxicity." Journal of the American College of Toxicology 7, no. 2 (March 1988): 221–42. http://dx.doi.org/10.3109/10915818809014521.

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This report presents a comprehensive literature review of the thermal decomposition products of polypropylene evolved under pyrolytic and oxidative conditions and the acute toxicity of combustion products of this polymer. Generally, the pyrolysis products of polypropylene (300–700°C) were aliphatic saturated and unsaturated hydrocarbons. The combustion of polypropylene in air (200–600°C) produced oxygenated hydrocarbons, aromatic hydrocarbons, aliphatic hydrocarbons, CO, CO2, and H2O. In general, as combustion temperature and time increased, the proportions of oxygenated and aliphatic hydrocarbons decreased, whereas the proportion of aromatic hydrocarbons increased. Using the University of San Francisco/National Aeronautical and Space Administration (USF/NASA) method under the fixed temperature program, time to death in mice caused by the combustion products of polypropylene decreased as the temperature was increased. Under the rising temperature mode, time to death decreased when polypropylene was combusted under airflow as compared to no airflow conditions. CO levels generated by the combustion of polypropylene were sufficient to produce the lethal effects observed. Using a test method developed at the University of Michigan, the combustion products of polypropylene were found to be 26 times more toxic under dynamic conditions (rising temperature) than under static conditions (fixed temperature).

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Nematollahi, Hossein, Nasim Moradi, Morteza RiyaziNejad, and Hossein Vahidi. "Removal of Aliphatic Hydrocarbons from Gas Oil Contaminated Clay Soil via Soil Vapor Extraction." Civil Engineering Journal 4, no. 8 (August 27, 2018): 1858. http://dx.doi.org/10.28991/cej-03091120.

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In this research, the performance of soil vapor extraction (SVE) for the removal of aliphatic hydrocarbons from gas oil contaminated soil and the effect of soil type on this method is studied. To explore the effect of soil type in the removal of hydrocarbons, SVE tests were conducted on 3 types of soil: 1) fine sand, 2) fine sand with 20% of kaolinite clay and 3) fine sand with 40% of kaolinite clay. Three extraction periods of 8, 16 and 24 hours were used. The results have shown that the efficiency of this method exceeds 78% in the removal of all hydrocarbons from fine sand, while an increase in clay significantly decreases the efficiency. Accordingly, the efficiency of this method decreases by 53.1% and 54.6% in fine sand with 20% of clay and fine sand with 40% of clay respectively. Furthermore, the results show that the higher concentration of some heavy and medium hydrocarbon leads to the more increase in early hours of SVE process, which indicates the alteration of hydrocarbons into each other.

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TAKAGI, M., N. UEMURA, and K. FURUHASHI. "Microbial Transformation Processes of Aliphatic Hydrocarbons." Annals of the New York Academy of Sciences 613, no. 1 Enzyme Engine (December 1990): 697–701. http://dx.doi.org/10.1111/j.1749-6632.1990.tb18248.x.

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Timmons, R. B., W. L. Jang, and Y. He. "Catalytic hydrodehalogenation of polyhalogenated aliphatic hydrocarbons." Zeolites 15, no. 3 (March 1995): 283. http://dx.doi.org/10.1016/0144-2449(95)90051-9.

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Cronin, John R., and Sandra Pizzarello. "Aliphatic hydrocarbons of the Murchison meteorite." Geochimica et Cosmochimica Acta 54, no. 10 (October 1990): 2859–68. http://dx.doi.org/10.1016/0016-7037(90)90020-l.

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36

Farjadfard, Sima, Seyyed Mehdi Borghei, Amir Hessam Hassani, Bagher Yakhchali, Mehdi Ardjmand, and Majid Zeinali. "Efficient biodegradation of naphthalene by a newly characterized indigenous Achromobacter sp. FBHYA2 isolated from Tehran Oil Refinery Complex." Water Science and Technology 66, no. 3 (August 1, 2012): 594–602. http://dx.doi.org/10.2166/wst.2012.217.

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A bacterial strain, FBHYA2, capable of degrading naphthalene, was isolated from the American Petroleum Institute (API) separator of the Tehran Oil Refinery Complex (TORC). Strain FBHYA2 was identified as Achromobacter sp. based on physiological and biochemical characteristics and also phylogenetic similarity of 16S rRNA gene sequence. The optimal growth conditions for strain FBHYA2 were pH 6.0, 30 °C and 1.0% NaCl. Strain FBHYA2 can utilize naphthalene as the sole source of carbon and energy and was able to degrade naphthalene aerobically very fast, 48 h for 96% removal at 500 mg/L concentration. The physiological response of Achromobacter sp., FBHYA2 to several hydrophobic chemicals (aliphatic and aromatic hydrocarbons) was also investigated. No biosurfactant was detected during bacterial growth on any aliphatic/aromatic hydrocarbons. The results of hydrophobicity measurements showed no significant difference between naphthalene- and LB-grown cells. The capability of the strain FBHYA2 to degrade naphthalene completely and rapidly without the need to secrete biosurfactant may make it an ideal candidate to remediate polycyclic aromatic hydrocarbon (PAH)-contaminated sites.

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Ravishankar, S., David C. Tilotta, Kenneth W. Busch, and Marianna A. Busch. "Spatial Emission Characteristics of a Capillary-Burner Excitation Source for a Flame Infrared Emission (FIRE) Radiometer." Applied Spectroscopy 45, no. 10 (December 1991): 1684–94. http://dx.doi.org/10.1366/0003702914335102.

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A complete mapping of the lateral and radial intensities of the 4.4- μm emission (antisymmetric CO2 stretch) resulting from the direct introduction of carbon dioxide, a homologous series of aliphatic hydrocarbons, and benzene into a hydrogen/air combustion flame supported on a capillary burner has been carried out. Both concentrated (99% methane, ethane, propane, and butane) and dilute (1% methane, ethane, propane, and benzene) hydrocarbons were studied. Flame profiles produced by the introduction of carbon dioxide were used to indicate the effects of local variations in source temperature and carbon dioxide number density in the absence of combustion. The radial profiles produced by the introduction of carbon dioxide and the hydrocarbons revealed a considerable amount of off-axis emission, believed to result from a zone of low temperature along the central vertical axis of the burner. Combustion of analyte appeared to be a diffusion-controlled process. For aliphatic hydrocarbons, combustion produced nearly quantitative amounts of carbon dioxide, provided the flame was not overloaded. For benzene, combustion produced particulate carbon, and the resulting blackbody emission was not strictly related to analyte concentration or carbon number. Blackbody emission may also result from the incomplete combustion of longer chain aliphatic hydrocarbons (propane and butane), if the burner is overloaded.

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38

Sotsky, J. B., C. W. Greer, and R. M. Atlas. "Frequency of genes in aromatic and aliphatic hydrocarbon biodegradation pathways within bacterial populations from Alaskan sediments." Canadian Journal of Microbiology 40, no. 11 (November 1, 1994): 981–85. http://dx.doi.org/10.1139/m94-157.

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A significant proportion of the naturally occurring hydrocarbon-degrading populations within Alaskan sediments affected by the Exxon Valdez oil spill had both the xylE and alkB genes and could convert hexadecane and naphthalene to carbon dioxide; a greater proportion of the population had xylE than had alkB, reflecting the composition of the residual oil at the time of sampling; nearly equal populations with xylE alone, alkB alone, and xylE + alkB genes together were found after exposure to fresh crude oil; populations with xylE lacking alkB increased after enrichment on naphthalene. Thus, the genotypes of hydrocarbon-degrading populations reflected the composition of the hydrocarbons to which they were exposed.Key words: hydrocarbon biodegradation, aromatic hydrocarbon biodegradation, aliphatic hydrocarbon biodegradation, alkB, xylE.

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Bogdanov, Jane B., and Bogdan Bogdanov. "New convenient vapor pressure-temperature correlation for some aliphatic hydrocarbons." Macedonian Journal of Chemistry and Chemical Engineering 32, no. 1 (June 15, 2013): 109. http://dx.doi.org/10.20450/mjcce.2013.105.

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New empirical equations for correlating temperature dependence of vapor pressure for C6-C20 aliphatic hydrocarbons are proposed: ln(VP) = k1·T/(k2+T) where, VP – vapor pressure, T – temperature, k1 – asymptotic maximum vapor pressure, and k2 – temperature at which the vapor pressure has half of its maximum value. Descriptors k1, k2 and k1/k2 have physical meaning and are unique for a given liquid. This “uniqueness” can be exploited for quantitative description of vapor pressure-temperature curve. The equation given above can be transformed algebraically into other convenient forms for plotting experimental data such as: T/ln(VP) = intercept + slope·T k1 = 1/slope; k2 = intercept/slope These derived descriptors can be utilized for evaluation and comparison of properties of different liquids and liquid mixtures and can serve as additional parameters for analysis of liquid hydrocarbon-based fuels for internal combustion engines.

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40

Mikhailov, N. N., and L. S. Sechina. "Microstructural wettability of oil and gas condensate zones of the Karachaganak field." SOCAR Proceedings, SI2 (December 30, 2021): 17–22. http://dx.doi.org/10.5510/ogp2021si200551.

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The Karachaganak field is represented by gas condensate and oil zones, a convenient object for studying changes in microstructural wettability during the transition from one zone to another. Microstructural wettability was characterized by a hydrophobization coefficient, Ѳн, which determines the proportion of the pore surface area occupied by adsorbed hydrocarbons. It was found that Ѳн of the samples of the gas and gas condensate zones is the same (on average 0.140), the oil zone - on average 0.250. Analysis of the IR spectra of extracted hydrocarbons showed that the microstructural wettability of the oil zone contains more aromatic, aliphatic, oxidized and sulfur-containing structures and fewer branched structures than in the gas condensate zone. The microstructural wettability of carbonate reservoirs depends on the hydrocarbon composition of the adsorbed oil. Keywords: microstructural wettability; hydrophobic coefficient; hydrocarbons; spectral coefficients.

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NEMIROVSKAYA, I. A., P. O. ZAV'YALOV, and B. V. KONOVALOV. "LEVELS AND NATURE OF HYDROCARBONS IN THE SURFACE WATER SUSPENSION AND BOTTOM SEDIMENTS OF THE KERCH STRAIT." Meteorologiya i Gidrologiya, no. 6 (June 2022): 66–78. http://dx.doi.org/10.52002/0130-2906-2022-6-66-78.

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The results of studying the concentration and composition of hydrocarbons in the suspension of surface water and in the surface layer of bottom sediments in the Kerch Strait in July 2020 in comparison with 2019 and with earlier studies in other regions of the Black Sea are presented. Despite the high concentrations of aliphatic hydrocarbons (especially in the water of the strait (on average 78 μg/L) and in coarse-grained sediments (47 μg/g)), the composition of alkanes did not correspond to the oil composition due to the rapid transformation of petroleum aliphatic hydrocarbons. The factor analysis revealed that the pollution has two sources: the main, pyrogenic (from transport) and, to a lesser extent, the oil one.

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Chancelice, Ndjeumi Chrisdel, Ze Bilo’o Philémon, Mouthe Anombogo Ghislain Arnaud, and Ngassoum Martin Benoït. "Aliphatic Hydrocarbons Extraction from Oily Sludge using Kerosene." European Journal of Engineering Research and Science 5, no. 10 (October 2, 2020): 1137–41. http://dx.doi.org/10.24018/ejers.2020.5.10.1880.

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The National Petroleum Refinery of Cameroon is a crude oil refining company that generates large quantity of oily sludge. The extraction, identification and quantification of aliphatic hydrocarbons that can be recovered from oily sludge were assessed. The extraction was conducted following an experimental design and the distribution of the aliphatic hydrocarbons of the sludge was realized by using a simple gas chromatographic method. The extraction results showed that all the factors have positive effect on the extraction. It was also found that the highest concentration of 127992 ppm was obtained under experimental conditions of Ratio = 6:1, Temperature = 40°C, Contact time = 90 min.

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43

Chancelice, Ndjeumi Chrisdel, Ze Bilo’o Philémon, Mouthe Anombogo Ghislain Arnaud, and Ngassoum Martin Benoït. "Aliphatic Hydrocarbons Extraction from Oily Sludge using Kerosene." European Journal of Engineering and Technology Research 5, no. 10 (October 2, 2020): 1137–41. http://dx.doi.org/10.24018/ejeng.2020.5.10.1880.

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The National Petroleum Refinery of Cameroon is a crude oil refining company that generates large quantity of oily sludge. The extraction, identification and quantification of aliphatic hydrocarbons that can be recovered from oily sludge were assessed. The extraction was conducted following an experimental design and the distribution of the aliphatic hydrocarbons of the sludge was realized by using a simple gas chromatographic method. The extraction results showed that all the factors have positive effect on the extraction. It was also found that the highest concentration of 127992 ppm was obtained under experimental conditions of Ratio = 6:1, Temperature = 40°C, Contact time = 90 min.

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44

Pereira, J., F. A. Agblevor, and S. H. Beis. "The Influence of Process Conditions on the Chemical Composition of Pine Wood Catalytic Pyrolysis Oils." ISRN Renewable Energy 2012 (December 19, 2012): 1–9. http://dx.doi.org/10.5402/2012/167629.

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Pine wood samples were used as model feedstock to study the properties of catalytic fast pyrolysis oils. The influence of two commercial zeolite catalysts (BASF and SudChem) and pretreatment of the pine wood with sodium hydroxide on pyrolysis products were investigated. The pyrolysis oils were first fractionated using column chromatography and characterized using GC-MS. Long chain aliphatic hydrocarbons, levoglucosan, aldehydes and ketones, guaiacols/syringols, and benzenediols were the major compounds identified in the pyrolysis oils. The catalytic pyrolysis increased the polycyclic hydrocarbons fraction. Significant decreases in phthalate derivatives using SudChem and long chain aliphatics using BASF catalyst were observed. Significant amounts of aromatic heterocyclic hydrocarbons and benzene derivatives were formed, respectively, using BASF and SudChem catalysts. Guaiacyl/syringyl and benzenediols derivatives were partly suppressed by the zeolite catalysts, while the sodium hydroxide treatment enriched phenolic derivatives. Zeolite catalyst and sodium hydroxide were employed together; they showed different results for each catalyst.

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Giamalva, David H., Daniel F. Church, and William A. Pryor. "Kinetics of ozonation. 6. Polycyclic aliphatic hydrocarbons." Journal of Organic Chemistry 53, no. 15 (July 1988): 3429–32. http://dx.doi.org/10.1021/jo00250a005.

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Halecky, Martin, Jana Rousova, Jan Paca, Evguenii Kozliak, Wayne Seames, and Kim Jones. "Biofiltration of gasoline and diesel aliphatic hydrocarbons." Journal of the Air & Waste Management Association 65, no. 2 (January 21, 2015): 133–44. http://dx.doi.org/10.1080/10962247.2014.980016.

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47

Smith, B. V. "Chapter 5. Aliphatic compounds. Part (i) Hydrocarbons." Annual Reports Section "B" (Organic Chemistry) 82 (1985): 91. http://dx.doi.org/10.1039/oc9858200091.

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48

Smith, B. V. "Chapter 5. Aliphatic compounds. Part (i) Hydrocarbons." Annual Reports Section "B" (Organic Chemistry) 83 (1986): 77. http://dx.doi.org/10.1039/oc9868300077.

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Smith, B. V. "Chapter 5. Aliphatic compounds. Part (i) Hydrocarbons." Annual Reports Section "B" (Organic Chemistry) 84 (1987): 93. http://dx.doi.org/10.1039/oc9878400093.

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Thomas, S. E. "Chapter 5. Aliphatic compounds. Part (i) Hydrocarbons." Annual Reports Section "B" (Organic Chemistry) 85 (1988): 85. http://dx.doi.org/10.1039/oc9888500085.

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Journal articles on the topic 'Aliphatic hydrocarbons'

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