Journal articles: 'Hydrocarbons Aliphatic compounds'

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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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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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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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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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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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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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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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9

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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10

Hill, L., and S. E. Thomas. "Chapter 5. Aliphatic compounds. Part (i) Hydrocarbons." Annual Reports Section "B" (Organic Chemistry) 86 (1989): 87. http://dx.doi.org/10.1039/oc9898600087.

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11

Harrison, M. J., and S. E. Thomas. "Chapter 5. Aliphatic compounds. Part (i) Hydrocarbons." Annual Reports Section "B" (Organic Chemistry) 87 (1990): 101. http://dx.doi.org/10.1039/oc9908700101.

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12

HILL, L., and S. E. THOMAS. "ChemInform Abstract: Aliphatic Compounds. Part 1. Hydrocarbons." ChemInform 23, no. 23 (August 22, 2010): no. http://dx.doi.org/10.1002/chin.199223298.

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HARRISON, M. J., and S. E. THOMAS. "ChemInform Abstract: Aliphatic Compounds. Part 1. Hydrocarbons." ChemInform 25, no. 3 (August 19, 2010): no. http://dx.doi.org/10.1002/chin.199403257.

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14

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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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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Ryu, Jaihyunk, Jae Il Lyu, Dong-Gun Kim, Jung-Min Kim, Yeong Deuk Jo, Si-Yong Kang, Jin-Baek Kim, Joon-Woo Ahn, and Sang Hoon Kim. "Comparative Analysis of Volatile Compounds of Gamma-Irradiated Mutants of Rose (Rosa hybrida)." Plants 9, no. 9 (September 17, 2020): 1221. http://dx.doi.org/10.3390/plants9091221.

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Roses are one of the most important floricultural crops, and their essential oils have long been used for cosmetics and aromatherapy. We investigated the volatile compound compositions of 12 flower-color mutant variants and their original cultivars. Twelve rose mutant genotypes were developed by treatment with 70 Gy of 60Co gamma irradiation of six commercial rose cultivars. Essential oils from the flowers of the 18 genotypes were analyzed by gas chromatography–mass spectrometry. Seventy-seven volatile compounds were detected, which were categorized into six classes: Aliphatic hydrocarbons, aliphatic alcohols, aliphatic ester, aromatic compounds, terpene alcohols, and others. Aliphatic (hydrocarbons, alcohols, and esters) compounds were abundant categories in all rose flowers. The CR-S2 mutant had the highest terpene alcohols and oil content. Three (CR-S1, CR-S3, and CR-S4) mutant genotypes showed higher ester contents than their original cultivar. Nonacosane, 2-methylhexacosane, and 2-methyltricosane were major volatile compounds among all genotypes. Hierarchical cluster analysis (HCA) of the rose genotypes gave four groups according to grouping among the 77 volatile compounds. In addition, the principal component analysis (PCA) model was successfully applied to distinguish most attractive rose lines. These findings will be useful for the selection of rose genotypes with improved volatile compounds.

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Chortyk, O. T., I. E. Yates, and C. C. Reilly. "Changes in Cuticular Compounds of Developing Pecan Leaves." Journal of the American Society for Horticultural Science 120, no. 2 (March 1995): 329–35. http://dx.doi.org/10.21273/jashs.120.2.329.

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Leaf surface compounds of pecan [Carya illinoensis (Wangenh.) C. Koch] were analyzed with regard to developmental stage and to susceptibility to infection by Cladosporium caryigenum (Ell. et Lang. Gottwald). Immature and mature leaves of two resistant (`Elliott' and `Sumner') and two susceptible (`Wichita' and `Schley') cultivars were extracted with methylene chloride. Extracts were separated by silicic acid chromatography into polar and nonpolar fractions. Constituents of each fraction were subsequently separated by gas chromatography and were identified by gas chromatography-mass spectroscopy. Leaf surface constituents characterized included long-chain aliphatic hydrocarbons, aliphatic wax esters, triterpenoid constituents, aliphatic alcohols, fatty acids, and diacyl glycerides. The predominant surface compounds on immature leaves were lipids such as fatty acids, fatty alcohols, and glycerides. On mature leaves, lipids declined and aliphatic hydrocarbons and triterpenoids became predominant leaf surface constituents. The changes were observed for all cultivars, regardless of genotypic response to C. caryigenum. Thus, we conclude that cuticular chemicals change dramatically during leaf maturation but do not correlate with resistance to scab disease common to certain pecan cultivars.

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Argemí-Armengol, Immaculada, Daniel Villalba, Marc Tor, Cristina Pérez-Santaescolástica, Laura Purriños, José Manuel Lorenzo, and Javier Álvarez-Rodríguez. "The extent to which genetics and lean grade affect fatty acid profiles and volatile compounds in organic pork." PeerJ 7 (July 17, 2019): e7322. http://dx.doi.org/10.7717/peerj.7322.

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Niche production is intended to produce premium pork, but several husbandry factors may affect the meat fatty acid composition and aroma. Fatty acid profile (by GC-FID) of raw meat and volatile compounds (by SPME-GC–MS) of cooked meat were analysed in loin samples from two pig genetic types-75% Duroc (Du) and 50% Pietrain (Pi) rossbreds that were slaughtered at different weights (90 kg and 105 kg, respectively) to achieve similar target carcass fatness, and the outcome carcasses were balanced for lean grade groups (<60% or ≥60% lean) within genotypes. Genetic type did not affect fatty acids (FA) profile of meat. The leaner meat had lower C12:0 and C20:3n − 3, lower saturated fatty acids (SFA) and higher MUFA/SFA ratio content than the fattier meat. Short-chain alcohols were lower in Pietrain and in leaner pork compared to the samples from Duroc crossbreds and fattier pork. A greater amount of hexane,2,4,4-trimethyl (an aliphatic hydrocarbon) but lower carbon disulphide (sulphur compound) content was detected in pork from leaner compared to fattier pork. Higher aromatics hydrocarbons were exclusively associated with Duroc crossbreds, and lower aliphatic hydrocarbons with pigs classified as fattier. Most of the volatile compounds detected in the present study came from lipid oxidation.

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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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Burčul, Franko, Ivica Blažević, Mila Radan, and Olivera Politeo. "Terpenes, Phenylpropanoids, Sulfur and Other Essential Oil Constituents as Inhibitors of Cholinesterases." Current Medicinal Chemistry 27, no. 26 (July 23, 2020): 4297–343. http://dx.doi.org/10.2174/0929867325666180330092607.

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: Essential oils constituents are a diverse family of low molecular weight organic compounds with comprehensive biological activity. According to their chemical structure, these active compounds can be divided into four major groups: terpenes, terpenoids, phenylpropenes, and "others". In addition, they may contain diverse functional groups according to which they can be classified as hydrocarbons (monoterpenes, sesquiterpenes, and aliphatic hydrocarbons); oxygenated compounds (monoterpene and sesquiterpene alcohols, aldehydes, ketones, esters, and other oxygenated compounds); and sulfur and/or nitrogen containing compounds (thioesters, sulfides, isothiocyanates, nitriles, and others). : Compounds that act as cholinesterase inhibitors still represent the only pharmacological treatment of Alzheimer´s disease. Numerous in vitro studies showed that some compounds, found in essential oils, have a promising cholinesterase inhibitory activity, such as α-pinene, δ-3-carene, 1,8-cineole, carvacrol, thymohydroquinone, α- and β-asarone, anethole, etc. : Essential oils constituents are a diverse family of low molecular weight organic compounds with comprehensive biological activity. According to their chemical structure, these active compounds can be divided into four major groups: terpenes, terpenoids, phenylpropenes, and "others". In addition, they may contain diverse functional groups according to which they can be classified as hydrocarbons (monoterpenes, sesquiterpenes, and aliphatic hydrocarbons); oxygenated compounds (monoterpene and sesquiterpene alcohols, aldehydes, ketones, esters, and other oxygenated compounds); and sulfur and/or nitrogen containing compounds (thioesters, sulfides, isothiocyanates, nitriles, and others).

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Seagars, Dana J., and Joel Garlich-Miller. "Organochlorine Compounds and Aliphatic Hydrocarbons in Pacific Walrus Blubber." Marine Pollution Bulletin 43, no. 1-6 (January 2001): 122–31. http://dx.doi.org/10.1016/s0025-326x(00)00233-2.

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Pedersen, J. A., M. A. Yeager, and I. H. Suffet. "Characterization and mass load estimates of organic compounds in agricultural irrigation runoff." Water Science and Technology 45, no. 9 (May 1, 2002): 103–10. http://dx.doi.org/10.2166/wst.2002.0215.

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Investigations of agricultural chemicals in surface runoff typically target nutrients or specific pesticides; however, numerous other organic compounds are regularly applied to agricultural fields in pesticide formulations, irrigation water, soil amendments and fertilizers. Many of these compounds have toxicological significance. We conducted a broad spectrum analysis of surface runoff from individual irrigated agricultural fields in coastal southern California to characterize organic compounds amenable to analysis by gas chromatography-mass spectrometry and to estimate the mass flux of selected chemicals. Aqueous phase extracts contained several pesticides, as well as personal care product ingredients and pharmaceutically active compounds apparently derived from treated wastewater used for irrigation. Several compounds potentially associated with pesticide adjuvants were also present in aqueous phase extracts. Dissolved NOM constituents in water phase extracts included n-fatty acids, aliphatic alcohols and plant terpenoids. Tentatively identified compounds sorbed to suspended particles included pesticides, a fecal sterol, aliphatic and alicyclic hydrocarbons, aliphatic alcohols, aldehydes, and C14 and C16n-fatty acids and fatty acid esters. Bicyclic and polycyclic aromatic hydrocarbons were identified in both aqueous and suspended particle phases. Constituent concentrations, including total suspended solids (TSS), varied over the course of the sampled events by up to an order of magnitude, and typically were not correlated with flow. Variation in sorbed organic compound concentrations often did not parallel those for TSS concentration. Mass load estimates were strongly influenced by the choice of sampling interval.

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Arif, Y., and N. Lombarkia. "Variability Influence of the Volatile Compounds of Three Algerian Date Cultivars (Phoenix dactylifera L.) on Infestation Rates of the Date Moth [(Ectomyelois ceratoniae Zell. (Lepidoptera: Pyralidae)]." Cercetari Agronomice in Moldova 51, no. 3 (September 1, 2018): 111–24. http://dx.doi.org/10.2478/cerce-2018-0029.

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Abstract The date moth Ectomyelois ceratoniae Zeller (Lepidoptera; Pyralidae) is a serious pest for the dates production in Algerian oasis. Its dangerousness resides in its wide geographic distribution on various bioclimatics stages and his polyphagia on various hosts. In this context, to find out the impact of the dates volatile compounds on the date moth oviposition behavior. To do this, we conducted the following study, which is divided into two parts, one in the field and the other in the laboratory. This study investigated the effect of the biochemical profiles of three Algerian date cultivars (Deglet-Nour, Ghars and Degla-Beidha) on the infestation rates of the date moth. The monitoring infection rates in the field produced the following results: during the campaigns from 2011/2012 to 2014/2015 at the INRAA Sidi Mahdi-Touggourt station (Algeria), revealed that the cultivar Deglet-Nour is the most affected with a rate of 18.84%, followed by Ghars with 10.28% then Degla-Beidha with 6.66%. As for the extracts analysis of the three date cultivars with hexane were identified and quantifie via coupling gas chromatography / mass spectrometry (GC/MS). The analysis of the volatile compounds of the cultivars studied allowed to identify 110 compounds distributed in eight chemical classes (hydrocarbons (saturated aliphatic hydrocarbons, unsaturated aliphatic hydrocarbons, unsaturated monocyclic hydrocarbons, saturated monocyclic hydrocarbons, aromatic hydrocarbons, terpene hydrocarbons), alcohols, aldehydes, esters, ketones, amides, phenols and carboxylic acids), whose compounds are distributed as follows: 72 compounds for the Deglet-Nour, 38 compounds for the cultivar Ghars and 29 compounds for Degla-Beidha.

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Zhou, Jun, Xi Hua Du, Yan Chen, Zhi Min Zong, and Xian Yong Wei. "Identification of Soluble Organic Compounds from Shengli Lignite in Toluene/Ethanol Mixed Solvent." Advanced Materials Research 977 (June 2014): 42–46. http://dx.doi.org/10.4028/www.scientific.net/amr.977.42.

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Shengli lignite (SL) was extracted with toluene/ethanol at the condition of ultrasonic extraction and the dissolved matters was further analyzed with gas chromatography/mass spectrometry (GC/MS). 41 organic compounds (OCs) including aliphatic hydrocarbons, arenes, organoheteratom compounds and organo-silicon compound were detected. The analysis of these high-valued OCs from soluble SL can provide an important theoretical basis for non-fuel of lignite. Keywords: Shengli lignite; ultrasonic extraction; soluble organic compounds; GC/MS analysis

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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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Schuler, Bruno, Yunlong Zhang, Sara Collazos, Shadi Fatayer, Gerhard Meyer, Dolores Pérez, Enrique Guitián, et al. "Characterizing aliphatic moieties in hydrocarbons with atomic force microscopy." Chemical Science 8, no. 3 (2017): 2315–20. http://dx.doi.org/10.1039/c6sc04698c.

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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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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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29

Ouvrard, Carole, and John B. O. Mitchell. "Can we predict lattice energy from molecular structure?" Acta Crystallographica Section B Structural Science 59, no. 5 (September 25, 2003): 676–85. http://dx.doi.org/10.1107/s0108768103019025.

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By using simply the numbers of occurrences of different atom types as descriptors, a conceptually transparent and remarkably accurate model for the prediction of the enthalpies of sublimation of organic compounds has been generated. The atom types are defined on the basis of atomic number, hybridization state and bonded environment. Models of this kind were applied firstly to aliphatic hydrocarbons, secondly to both aliphatic and aromatic hydrocarbons, thirdly to a wide range of non-hydrogen-bonding molecules, and finally to a set of 226 organic compounds including 70 containing hydrogen-bond donors and acceptors. The final model gives squared correlation coefficients of 0.925 for the 226 compounds in the training set and 0.937 for an independent test set of 35 compounds. The success of such a simple model implies that the enthalpy of sublimation can be predicted accurately without knowledge of the crystal packing. This hypothesis is in turn consistent with the idea that, rather than being determined by the particular features of the lowest-energy packing, the lattice energy is similar for a number of hypothetical alternative crystal structures of a molecule.

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30

Marušić Radovčić, Nives, Helga Medić, Katarina Novina, Petra Vidinski, and Ivna Poljanec. "Influence of different pig genotype on aroma, colour and fatty acid composition of smoked dry-cured ham." Meso 21, no. 6 (2019): 548–61. http://dx.doi.org/10.31727/m.21.6.4.

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The aim of this study was to determine the influence of different genotypes of pigs ((Landrace x large Yorkshire) x Duroc (LYD) and Black Slavonian (BS) pig) on the colour, fat content and fatty acid composition of smoked dry-cured ham and identify volatile aroma-active compounds. The fat content was determined by applying the Smedes method and the composition of fatty acids by using the gas chromatography, while volatile aroma-active compounds were investigated by using the headspace-solid phase microextraction (HS-SPME) and the gas chromatography-mass spectrometry (GC-MS). Different genotypes of pigs did not show a statistically significant difference (p>0.05) in total fat content, but there was a difference in the proportion of individual fatty acids. We identified a total of 103 volatile compounds belonging to the following groups of chemical compounds: 19 aromatic hydrocarbons, 17 aliphatic hydrocarbons, 17 ketones, 15 phenols, 14 aldehydes, 11 alcohols, 5 acids, 2 terpenes and 1 sulphur compound. The most abundant chemical groups of compounds in samples of smoked dry-cured ham from LYD pigs were aldehydes, phenols and aromatic hydrocarbons, while the most abundant chemical groups of compounds in samples of smoked dry-cured ham of BS genotype were phenols, aldehydes and alcohols.

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31

Cui, Xin Tao, Yong Fa Zhang, Dong Liu Dong, and Yu Qiong Zhao. "GC-MS Analyzing of Coal Tar of Lignite Briquette from Low Temperature Pyrolysis." Applied Mechanics and Materials 472 (January 2014): 591–95. http://dx.doi.org/10.4028/www.scientific.net/amm.472.591.

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Distillation and GC-MS were employed to analysis the coal tar of low-temperature pyrolysis of lignite briquette by contrasting with standards: the fraction below 340°C in the tar distillates of brown coal tar accounted for 83.30% and the other greater than 340°C is pitch accounted for 16.32%. 34.00% of coal tar are hydrocarbons which are mainly consisted of fat aliphatic hydrocarbon and include few alkene and cycloparaffins. The content of phenolic compounds in coal tar, mainly comes from the fraction below 210°C, is 11.68%. 16.86% of coal tar is aromatic compounds which are mainly composed of substitutive derivative of polyalkylbenzene distributing in all kinds of fractions; and a small amount of aromatic compounds which is concentrated in the fraction below 300°C. The content of oxygen-containing, nitrogen-containing and heterocyclic compounds is 4.47%, 0.57%, 2.11%, respectively.

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32

Zorić, Martina, Saša Kostić, Marko Kebert, Nebojša Kladar, Biljana Božin, and Saša Orlović. "Volatile organic compounds of Tilia cordata Mill. from Serbia, in terms of ecosystem services." Topola, no. 206 (2020): 21–28. http://dx.doi.org/10.5937/topola2006021z.

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It is considered that different plant organic compounds, known as phytoncides are creditable for positive effects of Forest therapy on human health. Ongoing pandemic has also put these compounds in research focus considering potential use for novel corona virus treatment. This research was conducted in order to examine the potential of Tilia cordata Mill. considering volatile organic compounds (VOCs) content for the use in Forest therapy. In order to determine qualitative and quantitative content of phytoncides, as well the variability among genotypes growing in the same environmental conditions, leaf samples from genotypes of T. cordata were collected from the Fruška gora (Serbia) during 2019. VOCs determined in fresh herbal material were analyzed by HeadspaceGC/MS and VOCs determined in essential oil were obtained by GC/MS. The results showed the presence of 17 different phytoncides (monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons, oxygenated sesquiterpenes, aliphatic compounds and diterpenes) in all tested genotypes. According to the mean values of the obtained results, the most abundant classes of phytoncides among the examined genotypes were monoterpene hydrocarbons (87.05), followed by aliphatic compounds (36.59) and oxygenated sesquiterpenes (34.60). The highest coefficient of variation (CV) among phytoncide content in tested T. cordata genotypes has been observed within oxygenated monoterpenes (43.12%), sesquiterpene hydrocarbons (28.18%), and diterpenes (27.04%). Some individual monoterpene hydrocarbons, such as o-cymene (19.92%) and a-pinene (17.40%) had the highest CV in terms of its presence in analyzed genotypes. In addition, the principal component analysis (PCA) showed more notable clustering within the VOCs determined in essential oil in comparison to VOCs determined in fresh herbal material. Considering the phytoncide content detected in T. cordata leaves, this species has high potential for the use in human health improvement within Forest therapy.

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Ciganek, M., and J. Neca. "Chemical characterization of volatile organic compounds on animal farms." Veterinární Medicína 53, No. 12 (December 29, 2008): 641–51. http://dx.doi.org/10.17221/1969-vetmed.

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More than one hundred volatile organic substances were identified by gas chromatography and mass spectrometry (GC/MS) in the indoor and outdoor air, stable and farm road dust and farm soil samples from two pig and cattle farms in the South Moravian Region. Volatile fatty acids (acetic, propanoic, butanoic and pentanoic acids) and their esters dominated along with aldehydes (butanal, pentanal and hexanal) and 4-methylphenol in the indoor and outdoor air samples. Road dust and soil samples contained mainly volatile aromatic compounds (toluene, benzene, ethylbenzene, styrene and xylenes), aliphatic hydrocarbons (largely n-alkanes), dichloromethane and carbon disulphide. The health risks associated with particular volatile compounds detected in the indoor and outdoor samples from the farms need to be assessed.

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34

Kukina, Tat'yana Petrovna, Dmitriy Nikolayevich Shcherbakov, Nina Vital'yevna Panteleyeva, Ol'ga Iosifovna Sal'nikova, and Petr Vladimirovich Kolosov. "QUALITY AND QUANTITATIVE COMPOSITION OF SUNFLOWER OIL DEODORIZATION DISTILLATE." chemistry of plant raw material, no. 1 (March 5, 2020): 199–206. http://dx.doi.org/10.14258/jcprm.2020015909.

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The composition of the sunflower oil deodorization distillate has been investigated. 18 acidic components have been identified, more than 40% of the composition of the studied sample falls on linoleic acid with F-vitamin activity. More than 30 components of neutral nature have been found that are of interest as bioactive compounds. Of these, 10 are phytosterols, 14 are triterpene alcohols, 5 are tocopherols. The diterpene hydrocarbons, alcohols and acids of the kauran structure found in the composition of deodorization distillate indicate that the original sunflower oil was native, since it is known that kauran derivatives are a chemotaxonomic marker of many plants of the compositae family, including sunflower. In addition to the above compounds, hydrocarbons (more than a quarter of the unsaponifiable matter), both aliphatic and diterpenic, in the studied sample, was found. Aliphatic components are predominantly unsaturated, which may indicate their artifact origin, i.e. they are the products of the dehydration of aliphatic alcohols. Phytadiene isomers, products of phytol dehydration and isomerization, have been found. The data obtained indicate the prospects for the use of oil deodorization distillate as a source of bioactive substances, cosmetic ingredients and pharmaceutical components.

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35

McCue, T., S. Hoxworth, and A. A. Randall. "Degradation of halogenated aliphatic compounds utilizing sequential anaerobic/aerobic treatments." Water Science and Technology 47, no. 10 (May 1, 2003): 79–84. http://dx.doi.org/10.2166/wst.2003.0543.

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The objective of this research was to determine if either methanogenic or sulfidogenic reductive dechlorination could survive an alternating anaerobic/aerobic sequence to biologically transform halogenated aliphatic hydrocarbons (HACs), specifically tetrachloroethylene (PCE), trichloroethylene (TCE), cis-1,2 dichloroethylene (cDCE), trans-1,2 dichloroethylene (tDCE), 1,1 dichloroethylene (1,1DCE) and vinyl chloride (VC). This ability was considered to be a necessary prerequisite for complete anaerobic/aerobic mineralization of halogenated aliphatic hydrocarbons by a single microbial consortia. Chlorinated solvents, which are among the most common groundwater contaminants, have been partially dechlorinated using single-stage anaerobic environmental treatment strategies. Various types of bacteria typically reductively dechlorinate PCE and TCE to cDCE and VC in an anaerobic environment, including methanogens, sulfidogens, and homoacetogens. The problem lies in the fact that reductive dechlorination typically leads to an accumulation of daughter compounds (cDCE, VC) which are more toxic than their parent compounds (PCE, TCE). Furthermore, PCE and (to a lesser extent) TCE, are resistant to dechlorination in aerobic environments. In contrast, VC and cDCE are readily oxidized co-metabolically in an aerobic environment by methanotrophic bacteria, and others using oxygenases (e.g. toluene oxidizers). Results from this research showed that both methanogenic and sulfidogenic reductive dechlorination could resume after transient exposures to both oxygen and hydrogen peroxide (H2O2). In fact, for cycles as frequent as 10 days between aerobic treatment cycles, reductive dechlorination was observed to resume at rates at least as rapid as microcosms not exposed to aerobic treatments.

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36

Khan, Nida Tabassum, Namra Jameel, and Maham Jamil Khan. "Overview of Different Waste Treatment Methods." INTERNATIONAL JOURNAL OF APPLIED PHARMACEUTICAL SCIENCES AND RESEARCH 3, no. 03 (July 1, 2018): 33–35. http://dx.doi.org/10.21477/ijapsr.3.3.2.

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Wastes including chlorinated aliphatic hydrocarbons, refractory organic compounds, aromatic derivatives, radionuclides etc., poses a serious threat to the environment. Therefore numerous in situ /ex situ treatment method are formulated to remove or immobilize such contaminates occurring in soil, water or air to minimize its harmful effects.

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37

SAMANTA, SUMAN K., ASISH PAL, and SANTANU BHATTACHARYA. "AN INSIGHT INTO FIBER–SOLVENT MEDIATED MODULATION OF NANO-FIBRILLAR ORGANOGELS." International Journal of Nanoscience 10, no. 04n05 (August 2011): 547–54. http://dx.doi.org/10.1142/s0219581x11009374.

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The effect of gelation and the modulation of their properties with the variation of aliphatic hydrocarbon solvents, e.g., n-decane and n-dodecane have been presented for a homologous series of amides of L-alanine with fatty acids. The gelation properties of these compounds were studied by a number of physical methods including scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, rheology etc. It was found that the gelation properties vary with the chain length of the host aliphatic hydrocarbons. Scanning electron microscopic images showed modulation of the fiber diameters upon changing the solvent from n-decane to n-dodecane and this has been confirmed by the results obtained from small angle X-ray scattering studies independently. Thermal properties were observed under the differential scanning calorimetric studies which showed an increase in the sol–gel transition temperatures upon increase in the chain length of the hydrocarbon solvent. The mechanical behavior of such assemblies has been observed under rheological experiments which showed a more viscoelastic response for the gels in n-decane compared to n-dodecane.

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38

Keeley, D. F., and J. R. Meriwether. "Hydrocarbons From U.S. Gulf Coast Geopressured Brines." Journal of Energy Resources Technology 110, no. 3 (September 1, 1988): 177–82. http://dx.doi.org/10.1115/1.3231379.

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U.S. Gulf Coast geopressured brines studied to date contain small amounts of C6+ hydrocarbons which are primarily aromatic in nature. They range from benzene to substituted anthracenes. In addition, the brines contain a variety of ions and light, C1 to C6, aliphatic hydrocarbons. The primarily aromatic hydrocarbon mixture was collected at −78.5°C and is referred to as a “cryocondensate.” It contains at least 95 different compounds and, from the carbon isotropic ratios, appears to be of terrestrial plant origin. For the only U.S. DOE geopressured energy design well studied for an extended period of time, i.e., the Glady’s McCall well, the concentration of the cryocondensate in the brine was observed to increase prior to the onset of oil production. It is postulated that the change in the brine cryocondensate concentration as a function of the cumulative brine volume produced from the wells results from an extraction of additional aromatic components from oil migrating into the production zone from adjacent shale. When sufficient oil has migrated, it is produced along with the brine.

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39

Jenkin, Michael E., Richard Valorso, Bernard Aumont, Andrew R. Rickard, and Timothy J. Wallington. "Estimation of rate coefficients and branching ratios for gas-phase reactions of OH with aliphatic organic compounds for use in automated mechanism construction." Atmospheric Chemistry and Physics 18, no. 13 (July 4, 2018): 9297–328. http://dx.doi.org/10.5194/acp-18-9297-2018.

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Abstract. Reaction with the hydroxyl (OH) radical is the dominant removal process for volatile organic compounds (VOCs) in the atmosphere. Rate coefficients for reactions of OH with VOCs are therefore essential parameters for chemical mechanisms used in chemistry transport models, and are required more generally for impact assessments involving the estimation of atmospheric lifetimes or oxidation rates for VOCs. Updated and extended structure–activity relationship (SAR) methods are presented for the reactions of OH with aliphatic organic compounds, with the reactions of aromatic organic compounds considered in a companion paper. The methods are optimized using a preferred set of data including reactions of OH with 489 aliphatic hydrocarbons and oxygenated organic compounds. In each case, the rate coefficient is defined in terms of a summation of partial rate coefficients for H abstraction or OH addition at each relevant site in the given organic compound, so that the attack distribution is defined. The information can therefore guide the representation of the OH reactions in the next generation of explicit detailed chemical mechanisms. Rules governing the representation of the subsequent reactions of the product radicals under tropospheric conditions are also summarized, specifically their reactions with O2 and competing processes.

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40

Carneiro, Maria Eulália Rocha, Rogério Migueis Picado, Cinthia Masumoto, Leonardo Mitidiero Mansor, Märcia Caruso Bícego, Eduineti Ceci Pereira Moreira de Sousa, and Bauer Raehid. "HYDROCARBONS DETECTION IN A COASTAL LAGOON IMPACTED BY AN OIL SPILL IN SÃO SEBASTIÃO CHANNEL, SÃO PAULO STATE, BRAZIL1." International Oil Spill Conference Proceedings 2005, no. 1 (May 1, 2005): 777–85. http://dx.doi.org/10.7901/2169-3358-2005-1-777.

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ABSTRACT An operational problem involving the loading arms occurred at São Sebastião Oil Terminal of PETROBRAS, located in the Brazilian Southeastern coast, during the oil transference from the tanker to the Terminal, resulting in the spill of approximately 26.0 m3 of crude Marlin-33 oil on 3 June 2003. The spilled bulk oil was transported by wind-driven currents to the north of São Sebastião Channel where skimmer vessels and booms collected the product. In spite of all contingency actions, some of the oil reached a coastal lagoon. The Environmental Monitoring Program, involving sampling a week and four months after the event, included chemical analysis for benzene, toluene, ethybenzene and xylenes (BTEX), petroleum hydrocarbons (TPH), aliphatic compounds (n-alkanes), polycyclic aromatic compounds (PAH), unresolved complex mixtures (UCM) and total organic carbon (TOC); toxicological tests for water using the Microtox system and Lytechinus variegatus embryo test, and for sediment using the Nitokra copepod test; and hydrocarbon detection in mussel tissue, related to local aquaculture. The coastal water PAH concentrations after the spill ranged from 0.14 to 1.92 μg/L in chrysene equivalents. For the lagoon water analysis, the concentrations of PAHs ranged from 1.54 to 9.66 μg/L. The total PAH concentrations in lagoon sediment ranged from 5.6 to 359.2 ng/g with perilene prevalence. The total PAH concentrations in mussel tissue samples ranged below the detection limit to 110.0 ng/g; the aliphatic hydrocarbon concentrations varied between 11.02 to 21.36 μg/g and total n-alkanes between 4.80 to 6.21 μg/g, showing no influence of petroleum hydrocarbons. The toxicity results were not conclusive: by means of acute tests, no toxicity was observed in the lagoon water. However, the chronic tests indicated toxicity in some samples including in the controls located in non-affected places.

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41

Tanemura, Kiyoshi, Tsuneo Suzuki, Yoko Nishida, and Takaaki Horaguchi. "Chlorination of aliphatic hydrocarbons, aromatic compounds, and olefins in subcritical carbon tetrachloride." Tetrahedron Letters 49, no. 45 (November 2008): 6419–22. http://dx.doi.org/10.1016/j.tetlet.2008.08.082.

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42

Tsonopoulos, Constantine, and Douglas Ambrose. "Vapor−Liquid Critical Properties of Elements and Compounds. 6. Unsaturated Aliphatic Hydrocarbons." Journal of Chemical & Engineering Data 41, no. 4 (January 1996): 645–56. http://dx.doi.org/10.1021/je9501999.

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43

Gearing, Juanita N., Dale E. Buckley, and John N. Smith. "Hydrocarbon and Metal Contents in a Sediment Core from Halifax Harbour: A Chronology of Contamination." Canadian Journal of Fisheries and Aquatic Sciences 48, no. 12 (December 1, 1991): 2344–54. http://dx.doi.org/10.1139/f91-275.

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In a dated core from the Northwest Arm of Halifax Harbour, pollutant hydrocarbon concentrations have increase 100-fold since about 1900 (15–20 cm depth). Aliphatic contaminants characteristic of sewage and urban runoff have had a steady, exponential growth overtime, while aromatic hydrocarbon combustion products are currently declining slightly from a subsurface maximum around 1950 (5–10 cm depth). Present levels of these compounds are among the highest reported in the literature. Similarly, contamination of sediments by the metals Cu, Zn, Pb, and Hg has also increased from 1890 to 1970, with maximum levels among the highest reported from other urban and industrialized coastal marine areas in the world. In contrast, the concentrations of natural product hydrocarbons such as squalene and perylene have not changed significantly in this century.

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44

Etteieb, Selma, Atsushi Kawachi, Junkyu Han, Foued Elayni, Jamila Tarhouni, and Hiroko Isoda. "Assessment of organic micropollutants occurrence in treated wastewater using heat shock protein 47 stress responses in Chinese hamster ovary cells and GC/MS-based non-target screening." Water Science and Technology 74, no. 10 (September 8, 2016): 2407–16. http://dx.doi.org/10.2166/wst.2016.426.

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Combining bioassays and analytical chemistry screening is a powerful approach to assess organic micropollutants which are the main contributors to toxic potential in complex mixtures of treated wastewater (TWW). The aim of this study was to perform a comprehensive toxicity assessment of treated effluents using stress response bioassays and then to assess the occurrence of the organic micropollutants which were responsible for this biological response using gas chromatography coupled with a mass spectrometry detector (GC/MS). Results showed that TWW samples induced significant stress response on Chinese hamster ovary cells, stably transfected with heat shock protein 47 promoter, at 0.1%, 1%, 5% and 10% concentrations. The organic chemical compounds responsible for stress response potential were identified at different percentage values using non-target chemical screening. Of the compounds detected in TWW1 and TWW4, 55.09% and 74.5% respectively, fell within the class of aliphatic hydrocarbons. Aliphatic hydrocarbons were also present in TWW3 at 26.46% whereas 11.96% corresponded to 6-acetyl-1,1,2,4,4,7-hexamethyltetralin and 16.08% to triethoxysilane. Moreover, 76.73% of TWW2 was recorded as decamethylcyclopentasiloxane (D5) and 17.44% as n-hexadecanoic acid.

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45

Rethemeyer, Janet, Christiane Kramer, Gerd Gleixner, Guido L. B. Wiesenberg, Lorenz Schwark, Nils Andersen, Marie-J. Nadeau, and Pieter M. Grootes. "Complexity of Soil Organic Matter: AMS 14C Analysis of Soil Lipid Fractions and Individual Compounds." Radiocarbon 46, no. 1 (2004): 465–73. http://dx.doi.org/10.1017/s0033822200039771.

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Radiocarbon measurements of different lipid fractions and individual compounds, isolated from soil samples collected on 2 different agricultural long-term study sites, located in the rural area of Rotthalmünster (Germany) and in the city of Halle/Saale (Germany), were analyzed to obtain information about sources and the stability of soil organic matter (SOM). Different lipid compound classes were isolated by automated solvent extraction and subsequent medium-pressure liquid chromatography. Generally, 14C contents of lipid compound classes from topsoil samples of maize plots at Rotthalmünster are close to the modern atmospheric 14C content. Lower 14C values of aliphatic and aromatic hydrocarbons isolated from neutral lipids suggest a contribution of old carbon to these fractions. In contrast, 14C values of bulk soil (52 pMC) as well as isolated lipid classes from Halle are highly depleted. This can be attributed to a significant contribution of fossil carbon at this site. Extremely low 14C contents of aromatic (7 pMC) and aliphatic hydrocarbons (19 pMC) reflect the admixture of fossil hydrocarbons at the Halle site. Individual phospholipid fatty acids (PLFA), which are used as a proxy for viable microbial biomass, were isolated by preparative capillary gas chromatography (PCGC) from topsoils at Rotthalmünster and Halle. PLFA 14C values are close to atmospheric 14C values and, thus, indicate a clear microbial preference for relatively young SOM. At Rotthalmünster, the 14C concentration of short-chain unsaturated PLFAs is not significantly different from that of the atmosphere, while the saturated PLFAs show a contribution of sub-recent SOM extending over the last decades. At Halle, up to 14% fossil carbon is incorporated in PLFAs n-C17:0 and cy-C18:0, which suggests the use of fossil carbon by soil microorganisms. Moreover, it can be concluded that the 14C age of soil carbon is not indicative of its stability.

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46

Colombo, Juan C., Claudio Bilos, Mauricio Remes Lenicov, Dario Colautti, Patricia Landoni, and Charles Brochu. "Detritivorous fish contamination in the Río de la Plata estuary: a critical accumulation pathway in the cycle of anthropogenic compounds." Canadian Journal of Fisheries and Aquatic Sciences 57, no. 6 (June 1, 2000): 1139–50. http://dx.doi.org/10.1139/f00-031.

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Aliphatic hydrocarbons, chlorinated pesticides, polychlorinated biphenyls (PCBs), dioxins, furans, and trace metals have been quantified in fishes collected at four stations in Río de la Plata to determine contaminant sources, elucidate interstation and interspecies differences, and assess the health risks associated with fish consumption. Río de la Plata fish present low trace metal concentrations and moderate to high levels of organic pollutants, particularly aliphatic hydrocarbons and PCBs. The highest concentrations were recorded in Prochilodus lineatus, a dominant and remarkably specialized fatty detritivore that feeds on contaminated organic-rich flocculent matter. Lower levels were registered in Cyprinus carpio and especially in Mugil cephalus, reflecting different feeding preferences. A geographical pattern of higher contaminant concentrations close to the Buenos Aires urban center and lower levels in distant stations was also observed. The multivariate analysis of contaminant signatures indicated that most contaminated Prochilodus had fresh petrogenic and PCB traces, similar to fossil fuels and Aroclor 1254-1260, whereas Mugil and fish from distant sites presented a higher proportion of biogenic hydrocarbons and of more chlorinated PCBs. Toxicity equivalents ranged from 11 to 39 pg·g fresh weight-1 in Prochilodus, exceeding the guideline of 25 pg·g-1 for human consumption, with allowable consumption rates as low as 1 g fish·day-1.

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47

Bendiabdellah, Amel, Mohammed El Amine Dib, Nawel Meliani, Alain Muselli, Djabou Nassim, Boufeldja Tabti, and Jean Costa. "Antibacterial Activity ofDaucus crinitusEssential Oils along the Vegetative Life of the Plant." Journal of Chemistry 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/149502.

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The essential oils from the aerial parts ofDaucus crinitusDesf. were analyzed at three developmental stages (early vegetative, early flowering, and full flowering). Oil yield was found to vary depending on the stage of development, and the highest content of oil (0.15% w/w) was obtained at full flowering. The chemical composition of essential oils studied by GC and GC-MS showed a total of 71 compounds: 27 aliphatic compounds, 18 sesquiterpene hydrocarbons, 9 hydrocarbons monoterpene, 5 oxygenated monoterpenes, 5 phenolic compounds, 4 oxygenated sesquiterpenes, 2 oxygenated diterpenes, and 01 diterpene hydrocarbons. Whatever the analyzed stage, phenolic compounds were the most abundant group. Their level significantly increased during ripening and varied from 36.4 to 82.1%. Antimicrobial activities of oils were tested on four different microorganisms. The oils of various phenological stages showed high activity againstCandida albicans(30 mm) andStaphylococcus aureus(11–28 mm) bacteria strains which are deemed very dangerous and very difficult to eliminate. Thus, they represent an inexpensive source of natural antibacterial substances that may potentially be used in pathogenic systems.

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48

Tsuchiya, Y., and A. Matsumoto. "Identification of Volatile Metabolites Produced by Blue-Green Algae." Water Science and Technology 20, no. 8-9 (August 1, 1988): 149–55. http://dx.doi.org/10.2166/wst.1988.0236.

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Some of the volatile metabolites of eight species of blue-green algae of the genera Oscillatoria, Phormidium, Aphanizomenon, and Anabaena were identified by gas chromatography mass spectrometry (GC-MS). As a result, five sesquiterpene alcohols (C15H26O) and two sesquiterpene hydrocarbons (germacrene-D and γ-cadi-nene) were detected in the cultures of Oscillatoriasplendida. O. amoena, and Anabaenamacrospora. Three aliphatic hydrocarbons (n-heptadecane,1-heptadecene and 7-methylheptadecane) were also identified in the cultures of most of these algae. None of these compounds appeared to impart an unpleasant taste or odor to water supplies.

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49

Janssen, Dick B., and Wim de Koning. "Development and application of bacterial cultures for the removal of chlorinated aliphatics." Water Science and Technology 31, no. 1 (January 1, 1995): 237–47. http://dx.doi.org/10.2166/wst.1995.0053.

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The possibility of obtaining microbial cultures for the degradation of halogenated aliphatic hydrocarbons is mainly determined by the diversity and activity of catabolic enzymes that exist in nature. If a suitable organism is available, applications for the treatment of different waste streams can be developed. The relation between the kinetic parameters of the key enzymes and the properties of the organisms relevant for such applications is discussed, both for growth supporting and cometabolic degradation. When growth on a chlorinated aliphatic compound is possible, development of a biological remediation process is likely to be relatively easy. This is illustrated with the degradation of 1,2-dichloroethane, a synthetic compound that can be mineralized by specific cultures. Closely related compounds may be recalcitrant, which can be understood from an examination of the degradative pathways. The development of biological treatment processes based on cometabolic degradation is more demanding because selection of the proper organisms and maintaining them in the process are not straightforward. The range of compounds that can be degraded cometabolically is significantly larger. The potential of obtaining improved degradation by genetic adaptation and the use of biofilms is discussed.

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Burger, Barend V., Desmond Slade, Marlize Z. Bekker, and Aron H. Goitom. "Mammalian exocrine secretions XIX. Chemical characterization of the interdigital secretion of the Black Wildebeest, Connochaetes gnou." Zeitschrift für Naturforschung C 75, no. 9-10 (September 25, 2020): 339–51. http://dx.doi.org/10.1515/znc-2019-0159.

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AbstractUsing gas chromatography (GC) in conjunction with electron impact mass spectrometry and retention-time comparison, 94 compounds, ranging from 2-methyl-2-propenal to octadecanoic acid, were identified in the interdigital secretions of male and female black wildebeests, Connochaetes gnou (also known as the white-tailed gnu). The constituents of these secretions belong to many different compound classes, including hydrocarbons, alcohols, aromatics and aliphatic carbonyl compounds including carboxylic acids as well as carboxylic acid esters. Relatively small quantitative differences were found between the male and female interdigital secretions. It was concluded that these compounds probably do not play a significant role in territorial marking or in chemical communication between males and females of the species, but they could be involved in preserving the remarkably strong attachment between members of social subgroups in black wildebeest populations.

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Journal articles on the topic 'Hydrocarbons Aliphatic compounds'

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