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Sample records for volatile hydrocarbon composition

  1. Process for producing volatile hydrocarbons from hydrocarbonaceous solids

    Energy Technology Data Exchange (ETDEWEB)

    1949-02-03

    In a process for producing volatile hydrocarbons from hydrocarbonaceous solids, a hydrocarbonaceus solid is passed in subdivided state and in the form of a bed downwardly through an externally unheated distilling retort wherein the evolution of volatiles from the bed is effected while solid material comprising combustible heavy residue is discharged from the lower portion of the bed and retort, combustibles are burned from the discharged solid material. The admixture resultant combustion gases with the vapours evolved in the retort is prevented, and a stream of hydrocarbon fluid is heated by indirect heat exchange with hot combustion gases produced by burning to a high temperature and is introduced into the distilling retort and direct contact with bed, supplying heat to the latter for effecting the evolution of volatiles from the hydrocarbonaceous solid. The improvement consists of subjecting the volatile distillation products evolved and removed from the bed to a fractionation and separating selected relatively light and heavy hydrocarbon fractions from the distillation products, withdrawing at least one of the selected fractions from the prcess as a product heating at least one other of the selected fractions to high temperature by the indirect heat exchange with hot combustion gases, and introducing the thus heated hydrocarbon fraction into direct contact with the bed.

  2. Radiation-induced volatile hydrocarbon production in platelets

    International Nuclear Information System (INIS)

    Radha, E.; Vaishnav, Y.N.; Kumar, K.S.; Weiss, J.F.

    1989-01-01

    Generation of volatile hydrocarbons (ethane, pentane) as a measure of lipid peroxidation was followed in preparations from platelet-rich plasma irradiated in vitro. The hydrocarbons in the headspace of sealed vials containing irradiated and nonirradiated washed platelets, platelet-rich plasma, or platelet-poor plasma increased with time. The major hydrocarbon, pentane, increased linearly and significantly with increasing log radiation dose, suggesting that reactive oxygen species induced by ionizing radiation result in lipid peroxidation. Measurements of lipid peroxidation products may give an indication of suboptimal quality of stored and/or irradiated platelets

  3. Measurement error potential and control when quantifying volatile hydrocarbon concentrations in soils

    International Nuclear Information System (INIS)

    Siegrist, R.L.

    1991-01-01

    Due to their widespread use throughout commerce and industry, volatile hydrocarbons such as toluene, trichloroethene, and 1, 1,1-trichloroethane routinely appears as principal pollutants in contamination of soil system hydrocarbons is necessary to confirm the presence of contamination and its nature and extent; to assess site risks and the need for cleanup; to evaluate remedial technologies; and to verify the performance of a selected alternative. Decisions regarding these issues have far-reaching impacts and, ideally, should be based on accurate measurements of soil hydrocarbon concentrations. Unfortunately, quantification of volatile hydrocarbons in soils is extremely difficult and there is normally little understanding of the accuracy and precision of these measurements. Rather, the assumptions often implicitly made that the hydrocarbon data are sufficiently accurate for the intended purpose. This appear presents a discussion of measurement error potential when quantifying volatile hydrocarbons in soils, and outlines some methods for understanding the managing these errors

  4. Biofuel components change the ecology of bacterial volatile petroleum hydrocarbon degradation in aerobic sandy soil

    International Nuclear Information System (INIS)

    Elazhari-Ali, Abdulmagid; Singh, Arvind K.; Davenport, Russell J.; Head, Ian M.; Werner, David

    2013-01-01

    We tested the hypothesis that the biodegradation of volatile petroleum hydrocarbons (VPHs) in aerobic sandy soil is affected by the blending with 10 percent ethanol (E10) or 20 percent biodiesel (B20). When inorganic nutrients were scarce, competition between biofuel and VPH degraders temporarily slowed monoaromatic hydrocarbon degradation. Ethanol had a bigger impact than biodiesel, reflecting the relative ease of ethanol compared to methyl ester biodegradation. Denaturing gradient gel electrophoresis (DGGE) of bacterial 16S rRNA genes revealed that each fuel mixture selected for a distinct bacterial community, each dominated by Pseudomonas spp. Despite lasting impacts on soil bacterial ecology, the overall effects on VHP biodegradation were minor, and average biomass yields were comparable between fuel types, ranging from 0.40 ± 0.16 to 0.51 ± 0.22 g of biomass carbon per gram of fuel carbon degraded. Inorganic nutrient availability had a greater impact on petroleum hydrocarbon biodegradation than fuel composition. Highlights: ► The effect of 10% ethanol or 20% biodiesel on the biodegradability of volatile petroleum hydrocarbons in soil was investigated. ► Competition for scarce inorganic nutrients between biofuel and VPH degraders slowed monoaromatic hydrocarbon degradation. ► Biofuel effects were transitional. ► Each fuel selected for a distinct predominant bacterial community. ► All bacterial communities were dominated by Pseudomonas spp. - Blending of petroleum with ethanol or biodiesel changes the fuel degrading soil bacterial community structure, but the long-term effects on fuel biodegradability are minor.

  5. Adsorption of volatile hydrocarbons in iron polysulfide chalcogels

    KAUST Repository

    Ahmed, Ejaz; Rothenberger, Alexander

    2014-01-01

    are found in micro (below 2 nm), meso (2-50 nm), and macro (above 50 nm) porous regions. These chalcogels possess optical bandgaps in the range of 1.55-2.70 eV. These aerogels have been studied for the adsorption of volatile hydrocarbons and gases. A much

  6. Influence of drying and irradiation on the composition of volatile compounds of thyme (Thymus vulgaris L.)

    International Nuclear Information System (INIS)

    Venskutonis, R.; Poll, L.; Larsen, M.

    1996-01-01

    An investigation of the influence of air-drying, freeze-drying, γ- and β-irradiation and storage for up to 10 months on the composition of volatile compounds in thyme herb (Thymus vulgaris L.) is presented. Altogether, 70 constituents were identified (53 positively and 17 tentatively), including those considered most important for thyme flavour. Quantitative results did not reveal significant differences in the composition of irradiated and non-irradiated samples, and the reduction of the amount of some volatile compounds after drying was comparable for air-dried and freeze-dried herb. The largest changes in flavour composition were observed during storage, especially the reduction in the concentration of monoterpene hydrocarbons

  7. Degradation of volatile hydrocarbons from steam-classified solid waste by a mixture of aromatic hydrocarbon-degrading bacteria.

    Science.gov (United States)

    Leahy, Joseph G; Tracy, Karen D; Eley, Michael H

    2003-03-01

    Steam classification is a process for treatment of solid waste that allows recovery of volatile organic compounds from the waste via steam condensate and off-gases. A mixed culture of aromatic hydrocarbon-degrading bacteria was used to degrade the contaminants in the condensate, which contained approx. 60 hydrocarbons, of which 38 were degraded within 4 d. Many of the hydrocarbons, including styrene, 1,2,4-trimethylbenzene, naphthalene, ethylbenzene, m-/p-xylene, chloroform, 1,3-dichloropropene, were completely or nearly completely degraded within one day, while trichloroethylene and 1,2,3-trichloropropane were degraded more slowly.

  8. Chemical Composition of the Semi-Volatile Grains of Comet 67P/Churyumov-Gerasimenko

    Science.gov (United States)

    Wurz, P.; Altwegg, K.; Balsiger, H. R.; Berthelier, J. J.; De Keyser, J.; Fiethe, B.; Fuselier, S. A.; Gasc, S.; Gombosi, T. I.; Korth, A.; Mall, U.; Reme, H.; Rubin, M.; Tzou, C. Y.

    2017-12-01

    Rosetta was in orbit of comet 67P/Churyumov-Gerasimenko from August 2014 to September 2016. On board is the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) experiment that has been continuously collecting data on the chemical composition and activity of the coma from 3.5 AU to pericentre at 1.24 AU and out again to 3.5 AU. ROSINA consists of two mass spectrometers, the Double Focusing Mass Spectrometer (DFMS) and the Reflectron-type Time-Of-Flight (RTOF), as well as the COmet Pressure Sensor (COPS). ROSINA recorded the neutral gas and thermal plasma in the comet's coma. The two mass spectrometers have high dynamic ranges and complement each other with high mass resolution, and high time resolution and large mass range. COPS measures total gas densities, bulk velocities, and gas temperatures. Occasionally, a dust grain of cometary origin enters the ion source of a ROSINA instrument where the volatile part evaporates since these ion sources are hot. The release of volatiles from cometary dust grains was observed with all three ROSINA instruments on several occasions. Because the volatile content of such a dust grain is completely evaporated after a few seconds, the RTOF instrument is best suited for the investigation of its chemical composition since complete mass spectra are recorded during this time. During the mission 9 dust grains were observed with RTOF during the October 2014 to July 2016 time period. It is estimated that these grains contain about 10-15 g of volatiles. The mass spectra were interpreted with a set of 75 molecules, with the major groups of chemical species being hydrocarbons, oxygenated hydrocarbons, nitrogen-bearing molecules, sulphur-bearing molecules, halogenated molecules and others. About 70% of these grains are depleted in water compared to the comet coma, thus, can be considered as semi-volatile dust grains, and the other about 30% are water grains. The chemical composition varies considerably from grain to grain

  9. Determination of the vertical distribution and areal of the composition in volatile oil and/or gas condensate reservoirs

    International Nuclear Information System (INIS)

    Santos Santos, Nicolas; Ortiz Cancino, Olga Patricia; Barrios Ortiz, Wilson

    2005-01-01

    The compositional variation in vertical and areal direction due to gravitational and thermal effects plays an important role in the determination of the original reserves in-situ and in the selection of the operation scheme for volatile oil and/or gas condensate reservoirs. In this work we presented the mathematical formulation of the thermodynamic behavior experienced by compositional fluids, such as volatile oil and/or gas condensate, under the influence of the mentioned effects (gravitational and thermal), which was implemented in a software tool, this tool determine the compositional variation in vertical direction and, in addition, it allows to know the saturation pressure variation in the hydrocarbon column and the location of the gas-oil contact. With the obtained results, product of the use of this tool, was developed a methodology to obtain one first approach of the compositional variation in areal direction to obtain compositional spatial distribution (iso composition maps) in the reservoir, for components like the methane, which experiences the greater variations. These iso composition maps allow to determine the location of the hydrocarbon deposits, in such a way that the production strategies can be selected and be applied to maximize the recovery, such as in fill wells, perforation of new zones, EOR processes, etc

  10. Holographic detection of hydrocarbon gases and other volatile organic compounds.

    Science.gov (United States)

    Martínez-Hurtado, J L; Davidson, C A B; Blyth, J; Lowe, C R

    2010-10-05

    There is a need to develop sensors for real-time monitoring of volatile organic compounds (VOCs) and hydrocarbon gases in both external and indoor environments, since these compounds are of growing concern in human health and welfare. Current measurement technology for VOCs requires sophisticated equipment and lacks the prospect for rapid real-time monitoring. Holographic sensors can give a direct reading of the analyte concentration as a color change. We report a technique for recording holographic sensors by laser ablation of silver particles formed in situ by diffusion. This technique allows a readily available hydrophobic silicone elastomer to be transformed into an effective sensor for hydrocarbon gases and other volatile compounds. The intermolecular interactions present between the polymer and molecules are used to predict the sensor performance. The hydrophobicity of this material allows the sensor to operate without interference from water and other atmospheric gases and thus makes the sensor suitable for biomedical, industrial, or environmental analysis.

  11. Comparison of the Chemical Composition of “Cystoseira sedoides (Desfontaines C. Agardh” Volatile Compounds Obtained by Different Extraction Techniques

    Directory of Open Access Journals (Sweden)

    Naima Bouzidi

    2016-01-01

    Full Text Available The volatile fraction of the brown alga Cystoseira sedoides (Desfontaines C.Agardh is prepared from the crude extract through the following three extraction methods: Hydrodistillation (HD, focused microwave assisted hydrodistillation (FMAHD and supercritical fluid extraction (SFE. The volatile fractions are analyzed by gas chromatography-flame ionization detector-mass spectrometry (GC-FID-MS, the chemical components are identified on the basis of the comparison of their retention indices with literature and their mass spectra with those reported in commercial databases. The chemical composition of the volatile fractions obtained by different extraction techniques fall into three major chemical classes: fatty acids and derivatives, sesquiterpenes, and hydrocarbons and derivatives. Others Compounds belonging to different chemical classes are found in that chemical composition.

  12. Adsorption of volatile hydrocarbons in iron polysulfide chalcogels

    KAUST Repository

    Ahmed, Ejaz

    2014-11-01

    We report the synthesis, characterization and possible applications of three new metal-chalcogenide aerogels KFe3Co3S 21, KFe3Y3S22 and KFe 3Eu3S22. Metal acetates react with the alkali metal polychalcogenides in formamide/water mixture to form extended polymeric frameworks that exhibit gelation phenomena. Amorphous aerogels obtained after supercritical CO2 drying have BET surface area from 461 to 573 m 2/g. Electron microscopy images and nitrogen adsorption measurements showed that pore sizes are found in micro (below 2 nm), meso (2-50 nm), and macro (above 50 nm) porous regions. These chalcogels possess optical bandgaps in the range of 1.55-2.70 eV. These aerogels have been studied for the adsorption of volatile hydrocarbons and gases. A much higher adsorption of toluene in comparison with cyclohexane and cyclopentane vapors have been observed. The adsorption capacities of the three volatile hydrocarbons are found in the following order: toluene > cyclohexane > cyclopentane. It has been observed that high selectivity in adsorption is feasible with high-surface-area metal chalcogenides. Similarly, almost an eight to ten times increase in adsorption selectivity towards CO2 over H2/CH4 was observed in the aerogels. Moreover, reversible ion-exchange properties for K+/Cs+ ions have also been demonstrated. © 2014 Elsevier Inc. All rights reserved.

  13. On the determination of diffusivities of volatile hydrocarbons in semi-solid bitumen

    International Nuclear Information System (INIS)

    Tang, J. S.

    2001-01-01

    Carbon dioxide, supercritical ethane and propane have been considered as solvents to recover heavy oil. Given that mixing solvent with bitumen is one of the important parameters governing the performance of the solvent extraction processes, good understanding of solvent dispersion is essential for the proper design of the process. Produced bitumen can still contain some residual volatile hydrocarbons after gas flashing off a three-phase separator. When exposed to the air due to a spill or ruptured line, these residual hydrocarbons can escape and create air pollution problems. Consequently, knowledge of the diffusivities of volatile components in bitumen is needed to assess the extent of environmental damage that may result from bitumen spill or working loss of vapour to the atmosphere. This paper discusses the de-coupled transfer model developed by this author (and described in a paper in vol. 78 of this journal) and its limiting solution, and provides a re-intrepretation of the method by Fu and Phillips (1979) which in turn was based on the late-time limiting solution advanced by Tang and Zhang (2000). The analysis indicates that gas purging is a valid method for determining the diffusion coefficients of trace, volatile hydrocarbons in bitumen. However, the assumption of de-coupling may not be appropriate for large diffusion flux and slow gas flow. Furthermore, improper use of the limiting solution theory could lead to a 25 per cent error in calculating the diffusion coefficient. 14 refs., 2 tabs., 8 figs

  14. The Volatile Composition of Portuguese Propolis Towards its Origin Discrimination

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    Soraia I. Falcão

    2016-03-01

    Full Text Available The volatiles from thirty six propolis samples collected from six different geographical locations in Portugal (mainland, Azores archipelago and Madeira Island were evaluated. Populus x canadensis Moenchen leaf-buds and Cistus ladanifer L. branches essential oils were comparatively analysed. The essential oils were isolated by hydrodistillation and analysed by Gas Chromatography (GC and Gas Chromatography-Mass Spectrometry (GC-MS. Cluster analysis based on propolis samples volatiles chemical composition defined three main clusters, not related to sample site collection. Cluster I grouped 28 samples with high relative amounts of oxygen-containing sesquiterpenes (20-77%, while cluster II grouped 7 samples rich in oxygen-containing monoterpenes (9-65% and the only sample from cluster III was monoterpene hydrocarbons rich (26%. Although Populus x canadensis and Cistus ladanifer were associated as resin sources of Portuguese propolis, other Populus species as well as plants like Juniperus genus may contribute to the resin in specific geographical locations.

  15. Volatile Composition of Smoked and Non-Smoked Iranian Rice

    Directory of Open Access Journals (Sweden)

    Leontina Lipan

    2016-11-01

    Full Text Available In this work, the volatile profiles of smoked and non-smoked Iranian rice were identified, and their relative abundance was calculated and compared. Headspace solid-phase microextraction together with gas chromatography-mass spectrometry (SPME-GC-MS were used to extract and identify the volatile compounds. The main groups of volatiles in Iranian rice were aldehydes, ketones, phenol derivatives, furans, linear hydrocarbons, esters and terpenes. The chemical family aldehydes was the most abundant one in the profile of non-smoked rice, while phenol derivatives and furans predominated in smoked samples. This study is the first one reporting comparative data of volatile compounds between smoked and non-smoked Iranian rice.

  16. [Composition characteristics of atmospheric volatile organic compounds in the urban area of Beibei District, Chongqing].

    Science.gov (United States)

    Qi, Xin; Hao, Qing-ju; Ji, Dong-sheng; Zhang, Jun-ke; Liu, Zi-rui; Hu, Bo; Wang, Yue-si; Jiang, Chang-sheng

    2014-09-01

    In order to study the composition and distribution of VOCs (Volatile Organic Compounds) in the atmosphere in the urban area of Beibei district, Chongqing, atmospheric samples were collected from March 2012 to February 2013 with special stainless steel cylinders, and analyzed with a three-stage preconcentration method coupled with GC-MS. 78 species of VOCs were detected in this study, of which there were 25 species of alkanes, 15 species of olefins, 28 species of aromatic hydrocarbons and 10 species of halogenated hydrocarbons. The results showed that the top seven species of VOCs according to the order of annual average concentration in the atmosphere of Beibei were: Dichloromethane (3. 08 x 10(-9) ) , Benzene (2. 09 x 10-9) , Isopentane (1. 85 x 10 -9) , Toluene (1. 51 x 10(-9)) , Propane (1. 51 x 10(-9)), m/p-xylene (1.43 x 10(-9)) and Styrene (1. 39 x 10-9). The concentration of TVOCs (Total Volatile Organic Compounds) in the atmosphere of Beibei was 33. 89 x 10 -9 during the measuring period, and the seasonal variation was obvious with the order of spring (42. 57 x 10 -9) > autumn (33.89 x 10-9) > winter (31.91 x 10 -9) > summer (27.04 x 10(-9)). In the composition of TVOCs, alkanes and aromatic hydrocarbons provided the largest contribution to TVOCs (31.5% and 30.7% ) , followed by halogenated hydrocarbon, accounting for 27.4% , and the last one was olefins, with only 10.4%. By means of ozone formation potential, the analysis results showed that olefins and aromatic hydrocarbon compounds were the two important materials which made the biggest contribution to the formation of ozone in the atmosphere of Beibei. We further analyzed the sources of VOCs in atmosphere of Beibei by the method of Principal Component Analysis (PCA). Vehicle exhaust was the biggest source and its contribution to VOCs was 50. 41%. The calculated results with T/B value also confirmed that traffic was the biggest source contributing to the VOCs in atmosphere of Beibei.

  17. Natural elimination of volatile halogenated hydrocarbons from the environment

    Energy Technology Data Exchange (ETDEWEB)

    Harress, H.M.; Grathwohl, P.; Torunski, H.

    1987-01-01

    Recently carried out field investigations of groundwater contaminations with volatile halogenated hydrocarbons have shown evidence of natural elimination of these hazardous substances. This elimination effects is rare and observed in connection with special geological conditions. With regard to some contaminated sites, the following mechanisms for this behaviour are discussed: 1. Stripping by naturally ascending gases. 2. Sorption on soil organic matter. 3. Biodegradation. The so far compiled knowledge allowed to develop further research programmes, which are pursued in various projects.

  18. Methodology for the detection of contamination by hydrocarbons and further soil sampling for volatile and semi-volatile organic enrichment in former petrol stations, SE Spain

    Directory of Open Access Journals (Sweden)

    Rosa María Rosales Aranda

    2012-01-01

    Full Text Available The optimal detection and quantification of contamination plumes in soil and groundwater by petroleum organic compounds, gasoline and diesel, is critical for the reclamation of hydrocarbons contaminated soil at petrol stations. Through this study it has been achieved a sampling stage optimization in these scenarios by means of the location of potential contamination areas before sampling with the application of the 2D electrical resistivity tomography method, a geophysical non destructive technique based on resistivity measurements in soils. After the detection of hydrocarbons contaminated areas, boreholes with continuous coring were performed in a petrol station located in Murcia Region (Spain. The drillholes reached depths down to 10 m and soil samples were taken from each meter of the drilling. The optimization in the soil samples handling and storage, for both volatile and semi-volatile organic compounds determinations, was achieved by designing a soil sampler to minimize volatilization losses and in order to avoid the manual contact with the environmental samples during the sampling. The preservation of soil samples was performed according to Europe regulations and US Environmental Protection Agency recommendations into two kinds of glass vials. Moreover, it has been taken into account the determination techniques to quantify the hydrocarbon pollution based on Gas Chromatography with different detectors and headspace technique to reach a liquid-gas equilibrium for volatile analyses.

  19. Feasibility study for application of the marine coral powder as a novel adsorbent for Volatile Organic Hydrocarbons

    Directory of Open Access Journals (Sweden)

    Alireza Mashkoori

    2015-06-01

    Full Text Available The marine coral has a porous outer surface and it has served in the processes such as water treatment systems, removal of carbon dioxide and adsorption of arsenic. Based on the need for cheap and efficient adsorbents, in sampling, the aim of this study, comparison of the efficiency of marine coral powder and activated charcoal in adsorption of volatile organic hydrocarbons was considered. In this experimental research, a certain concentrations of 8 volatile organic hydrocarbons: (para-Xylene, Chloroform, Carbon tetrachloride, tert-Butanol, Pyridine, Acetone, Ethyl acetate and Diethyl ether was injected into dynamic atmospheric chamber in the NTP (Normal Temperature and Pressure conditions. Air sampling was performed with the tube containing marine coral powder as well as the tube of activated charcoal, based on the standard method of NIOSH (National Institute of Occupational Safety and Health and in the same laboratory conditions. Then samples were injected into the gas Chromatograph apparatus and analytical comparison has been done between the amount of adsorption of hydrocarbons by activated charcoal and coral powder-test and Mann-Whitney were done with SPSS V.20.Findings showed that there was a significant difference between the amount of adsorption of Para-Xylene, carbon tetrachloride, tert-Butanol, Pyridine, acetone and Ethyl acetate hydrocarbons by activated charcoal and coral powder (P<0.05(. The amount of hydrocarbons adsorption by activated charcoal was, more than coral powder significantly (P<0.001. Based on the present research, in sampling of used hydrocarbons, the marine coral powder was less efficient than the activated charcoal, and it is recommended that more works be designed about other techniques such as coating of the marine coral powder in order to the improvement of adsorption capacity for volatile organic hydrocarbons.

  20. Volatile hydrocarbon profile of Iberian dry-cured hams. A possible tool for authentication of hams according to the fattening diet.

    Science.gov (United States)

    Narváez-Rivas, Mónica; Vicario, Isabel M; Alcalde, M Jesús; León-Camacho, Manuel

    2010-06-15

    The aims of this work were to carry out a comprehensive study of the volatile hydrocarbons of 34 Iberian dry-cured hams and to evaluate the efficiency of these compounds for discriminating hams according to the fattening system: "Montanera" (B) and "Cebo" (C). The samples of hams were obtained by mincing the semimembranosus and semitendinosus muscles from slices of dry-cured ham. The analyses were carried out by gas chromatography-mass spectrometry with a polar capillary column and after a previous extraction by Purge and Trap method. Forty-three volatile hydrocarbons were identified, 26 of them for the first time in Iberian dry-cured ham. Only five compounds showed significant differences between the two types of hams. Among the 33 volatile hydrocarbons, 22 of them allowed a complete discrimination of the two groups of hams according the fattening system.

  1. The analysis of semi-volatile and non-volatile petroleum hydrocarbons in a soil/sediment matrix by capillary column gas chromatography/flame ionization detection (GC/FID)

    International Nuclear Information System (INIS)

    George, J.E. III; Thoma, J.J.; Hastings, M.

    1990-01-01

    A comprehensive analysis for semi-volatile and non-volatile fractions of petroleum hydrocarbons can be achieved by a solvent extraction/concentration techniques that will effectively extract these high molecular weight fractions from a soil matrix. The prepared extract is then injected directly into a gas chromatograph equipped with a capillary column and flame ionization detector. This technique applies to the following types of commercially available petroleum hydrocarbons: Diesel Nos. 2,4,5, and 6, fuel oils and several grades of lubrication oil. The identification of a particular petroleum hydrocarbon is determined visually by comparison of the samples with known hydrocarbon standards. Accurate quantitation of the chromatograms is possible by using peak area summation and the presence of an internal standard. The practical quantitation limit for the method is 10 mg/Kg for most fuel types. This paper presents a method for determining the concentration of these fuel types in soil. Data will be presented only on 10W40 lubrication oil in terms of method validation, calibration, percent recovery, and method detection limits. A discussion of the quatitation techniques used will also be included

  2. Comparative Analysis of the Volatile Fraction of Fruit Juice from Different Citrus Species

    Science.gov (United States)

    Alamar, M. Carmen; Gutiérrez, Abelardo; Granell, Antonio

    2011-01-01

    The volatile composition of fruit from four Citrus varieties (Powell Navel orange, Clemenules mandarine, and Fortune mandarine and Chandler pummelo) covering four different species has been studied. Over one hundred compounds were profiled after HS-SPME-GC-MS analysis, including 27 esters, 23 aldehydes, 21 alcohols, 13 monoterpene hydrocarbons, 10 ketones, 5 sesquiterpene hydrocarbons, 4 monoterpene cyclic ethers, 4 furans, and 2 aromatic hydrocarbons, which were all confirmed with standards. The differences in the volatile profile among juices of these varieties were essentially quantitative and only a few compounds were found exclusively in a single variety, mainly in Chandler. The volatile profile however was able to differentiate all four varieties and revealed complex interactions between them including the participation in the same biosynthetic pathway. Some compounds (6 esters, 2 ketones, 1 furan and 2 aromatic hydrocarbons) had never been reported earlier in Citrus juices. This volatile profiling platform for Citrus juice by HS-SPME-GC-MS and the interrelationship detected among the volatiles can be used as a roadmap for future breeding or biotechnological applications. PMID:21818287

  3. Toxicity assessment of volatile organic compounds and polycyclic aromatic hydrocarbons in motorcycle exhaust.

    Science.gov (United States)

    Chang, Chang-Tang; Chen, Bor-Yann

    2008-05-30

    This study investigates the toxicity of various pollutant species from motorcycle exhaust via dose-response analysis and margin of safety using Escherichia coli DH5 alpha. The toxicity evaluation of the major components of motorcycle exhaust volatile organic compounds (VOCs), collected with impinger, and polycyclic aromatic hydrocarbons (PAHs), collected with filter and XAD-2, is essential to determine emission standards for motorcycles. The toxicity of benzene (B), toluene (T), ethyl benzene (E) and xylene (X) was selected for comparison as standard VOCs emitted from motorcycles. In addition, three types of reformulated gasoline (high oxygenate and high benzene content (No. 1), low oxygen and high benzene (No. 2), and low oxygen and low benzene (No. 3) were prepared to reveal combined toxicity of individual compositions. Motorcycle exhaust is significantly more toxic than BTEX due to the highly toxic VOCs generated from incomplete combustion. Overall toxicity evaluation showed that the toxicity, indicated as EC50, was approximately as follows: PAHs>two-stroke engines>four-stroke engines>BTEX.

  4. Toxicity assessment of volatile organic compounds and polycyclic aromatic hydrocarbons in motorcycle exhaust

    International Nuclear Information System (INIS)

    Chang, C.-T.; Chen, B.-Y.

    2008-01-01

    This study investigates the toxicity of various pollutant species from motorcycle exhaust via dose-response analysis and margin of safety using Escherichia coli DH5α. The toxicity evaluation of the major components of motorcycle exhaust volatile organic compounds (VOCs), collected with impinger, and polycyclic aromatic hydrocarbons (PAHs), collected with filter and XAD-2, is essential to determine emission standards for motorcycles. The toxicity of benzene (B), toluene (T), ethyl benzene (E) and xylene (X) was selected for comparison as standard VOCs emitted from motorcycles. In addition, three types of reformulated gasoline (high oxygenate and high benzene content (No. 1), low oxygen and high benzene (No. 2), and low oxygen and low benzene (No. 3) were prepared to reveal combined toxicity of individual compositions. Motorcycle exhaust is significantly more toxic than BTEX due to the highly toxic VOCs generated from incomplete combustion. Overall toxicity evaluation showed that the toxicity, indicated as EC 50 , was approximately as follows: PAHs > two-stroke engines > four-stroke engines > BTEX

  5. Polycyclic aromatic hydrocarbons and volatile organic compounds in biochar and biochar-amended soil: A review

    Science.gov (United States)

    Residual pollutants including polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), and carbon(aceous) nanoparticles are inevitably generated during the pyrolysis of waste biomass, and remain on the solid co-product called biochar. Such pollutants could have adverse effects on ...

  6. Characterization of volatile composition of Laurencia dendroidea by gas chromatography-mass spectrometry

    Directory of Open Access Journals (Sweden)

    Vanessa Gressler

    2012-05-01

    Full Text Available In this study we report the characterization of the volatile compounds of Laurencia dendroidea. Solvent extracts (dichloromethane and methanol, hydrodistillation extracts and headspace solid-phase microextraction samples were obtained and analyzed by GC-MS. Forty-six volatile components were identified in L. dendroidea, among them hydrocarbons, alcohols, phenols, aldehydes, ketones, acids, esters and terpenes.

  7. Volatile composition of peppermint (Mentha piperita L.) commercial teas through solid phase extraction.

    Science.gov (United States)

    Riachi, L G; Abi-Zaid, I E; Moreira, R F A; De Maria, C A B

    2012-12-01

    Volatiles from aqueous extract of peppermint commercial sachets were investigated through gas chromatography/flame ionization detection (GC/FID) and GC/mass spectrometry (MS). Samples were prepared under similar conditions as in homemade tea. Volatiles were isolated using solid phase extraction method (SPE) with Porapak Q trap followed by desorption with acetone. Estimated mean values for short and medium chain carboxylic acids (C2-C12) and ketones lay in the range of 50-64 microg kg(-1) whilst aliphatic alcohols and acyclic hydrocarbons had values lower than 6 microg kg(-1). The major volatiles were terpenes (275-382 microg kg(-1)) that reached 89 % of the total composition. A total of 16 compounds, among them dodecane, acetoin, acetol, citral, geraniol and octanoic acid have been described by the first time in peppermint tea. These findings could be attributed to the different analytical approach employed, mainly to the use of different extraction/pre-concentration techniques. Given the apparently lower proportion of terpenes in the aqueous extract it may be that the chemical properties of the peppermint essential oil are not entirely reproduced with homemade tea.

  8. Volatile Hydrocarbon Analysis in Blood by Headspace Solid-Phase Microextraction: The Interpretation of VHC Patterns in Fire-Related Incidents.

    Science.gov (United States)

    Waters, Brian; Hara, Kenji; Ikematsu, Natsuki; Takayama, Mio; Kashiwagi, Masayuki; Matsusue, Aya; Kubo, Shin-Ichi

    2017-05-01

    A headspace solid-phase microextraction (HS-SPME) technique was used to quantitate the concentration of volatile hydrocarbons from the blood of cadavers by cryogenic gas chromatography-mass spectroscopy. A total of 24 compounds including aromatic and aliphatic volatile hydrocarbons were analyzed by this method. The analytes in the headspace of 0.1 g of blood mixed with 1.0 mL of distilled water plus 1 µL of an internal standard solution were adsorbed onto a 100-µm polydimethylsiloxane fiber at 0°C for 15 min, and measured using a GC-MS full scan method. The limit of quantitation for the analytes ranged from 6.8 to 10 ng per 1 g of blood. This method was applied to actual autopsy cases to quantitate the level of volatile hydrocarbons (VHCs) in the blood of cadavers who died in fire-related incidents. The patterns of the VHCs revealed the presence or absence of accelerants. Petroleum-based fuels such as gasoline and kerosene were differentiated. The detection of C8-C13 aliphatic hydrocarbons indicated the presence of kerosene; the detection of C3 alkylbenzenes in the absence of C8-C13 aliphatic hydrocarbons was indicative of gasoline; and elevated levels of styrene or benzene in the absence of C3/C4 alkylbenzenes and aliphatic hydrocarbons indicated a normal construction fire. This sensitive HS-SPME method could help aid the investigation of fire-related deaths by providing a simple pattern to use for the interpretation of VHCs in human blood. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Essential Oil Composition and Volatile Profile of Seven Helichrysum Species Grown in Italy.

    Science.gov (United States)

    Giovanelli, Silvia; De Leo, Marinella; Cervelli, Claudio; Ruffoni, Barbara; Ciccarelli, Daniela; Pistelli, Luisa

    2018-03-06

    Helichrysum genus consists of about 600 species widespread throughout the world, especially in South Africa and in the Mediterranean area. In this study the aroma profile (HS-SPME) and the EO compositions of seven Helichrysum species (H. cymosum, H. odoratissimum, H. petiolare, H. fontanesii, H. saxatile, H. sanguineum, and H. tenax) were evaluated. All the plants were grown in Italy under the same growth conditions. The volatile constituents, particularly monoterpenes, depended by the plant's genotype and ecological adaptation. This study represents the first headspace evaluation on the selected plants and the results evidenced that monoterpenes represented the main class of constituents in five of the seven species analysed (from 59.2% to 95.0%). The higher content in sesquiterpene hydrocarbons was observed in the Mediterranean species of H. sanguineum (68.0%). Only H. saxatile showed relative similar abundance of monoterpenes and sesquiterpene hydrocarbons. The essential oil composition of the majority of examined species are characterised by high percentage of sesquiterpenes (especially β-caryophyllene and δ-cadinene) ranging from 51.3% to 92.0%, except for H. cymosum, H. tenax, and H. sanguineum leaves where monoterpenes predominated (from 51.7% to 74.7%). © 2018 Wiley-VHCA AG, Zurich, Switzerland.

  10. Hydrocarbon composition products of the catalytic recycling plastics waste

    Directory of Open Access Journals (Sweden)

    Zhaksyntay Kairbekov

    2013-09-01

    Full Text Available The paper represents the IR spectroscopy results of the hydrocarbon composition of products, which is obtained from catalytic processing of plastic wastes. The optimal conditions for the hydrogenation with to producny liquid of products are identified.  These liquid products are enriched with aromatics, paraffinic- naphthenic and unsaturated hydrocarbons. The main characteristics of the distillates received by hydrogenation of plastics (as density, refractive index, iodine number, pour point, cloud point, filtering, sulfur content,  fractional and composition of the hydrocarbon group.

  11. Predicting refinery effluent toxicity on the basis of hydrocarbon composition determined by GCxGC analysis

    Energy Technology Data Exchange (ETDEWEB)

    Whale, G. [and others

    2013-04-15

    A high resolution analytical method for determining hydrocarbon blocks in petroleum products by comprehensive two-dimensional gas chromatography (GCxGC) was used for the analysis of petroleum hydrocarbons extracted from refinery effluents. From 105 CONCAWE refineries in Europe 111 refinery effluents were collected in the period June 2008 to March 2009 (CONCAWE, 2010). The effluents were analysed for metals, standard effluent parameters (including Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), oil in water (OiW), GCxGC speciated hydrocarbons, BTEX (Benzene, Toluene, Ethylbenzene, and Xylenes) and volatile organic compounds. This report describes the subsequent analysis of the GCxGC data, as described in hydrocarbon blocks, and uses the PETROTOX model, to predict the environmental toxicity (i.e. ecotoxicity) of the discharged effluents. A further analysis was undertaken to address the potential environmental impact of these predicted effects initially using default dilution factors and then,when necessary site specific factors. The report describes all the methods used to arrive at the predictions, and shows that for the majority of refinery effluents direct toxicity effects in the effluents are not anticipated. Furthermore, when applying either the EU Risk Assessment Technical Guidance Document (TGD) default dilution factors or site specific dilution factors, none of the refineries are predicted to exerting either acute or chronic toxicity to organisms in the receiving aquatic environment, based on their hydrocarbon composition present in the effluent samples.

  12. Oil characterisation: assessment of composition, risks, degradation and remediation potential of total petroleum hydrocarbons in soil

    International Nuclear Information System (INIS)

    Lookman, R.; Vanermen, G.; Van De Weghe, H.; Gemoets, J.; Van der Sterren, G.; Alphenaar, A.

    2005-01-01

    Several methods are available for the characterization of petroleum hydrocarbons. The TPHCWG (Total Petroleum Hydrocarbon Criteria Working Group) developed a method based on a silica column separation of aromatics and aliphatics and a GC-FID subdivision into equivalent-carbon fractions (EC) ('TPH-method'). This method was mainly developed for assessing human risks of oil compounds. Within NOBIS (Dutch Research program Biological In-situ Remediation), another method was developed based upon an equilibrium-experiment of the oil-polluted soil with water (column recirculation), which was further developed by TTE ('TTE-method'). This method uses measured water solubilities of individual oil components and GC-retention times yielding a subdivision of the hydrocarbons into compound classes that are relevant for assessing the remediation potential of the specific oil pollution. In this paper we present results of a research project in which we developed a new method, the 'OK-method' that combines these two procedures and allows a complete characterisation of the oil in terms of composition, (human) risks, volatility, solubility, plume behaviour (migration velocities of the soluble components) and aerobic degradation potential. (authors)

  13. Chemical Investigations of Volatile Oil of Salvia yosgadensis Freyn et Bornm

    OpenAIRE

    ŞARER, Engin

    1988-01-01

    There are 44 endemic species of the Salvia genera growing in Anatolia. In this research, the physical properties and the chemical composition of the volatile oil of S. yosgadensis Freyn. et Bornm. as an endemic species have been investigated. The flowers and leaves of the plant contain 0.30 per cent volatile oil. In this oil 14 monoterpene hydrocarbons and 15 oxygen-containing compounds and sesquiter

  14. Associations between the sensory attributes and volatile composition of Cabernet Sauvignon wines and the volatile composition of the grapes used for their production.

    Science.gov (United States)

    Forde, Ciarán G; Cox, Agnieszka; Williams, Emlyn R; Boss, Paul K

    2011-03-23

    The sensory properties of wine are influenced by the chemical composition of the grapes used to produce them. Identification of grape and wine chemical markers associated with the attributes perceived by the consumer of the wine will enable better prediction of the potential of a parcel of grapes to produce wine of a certain flavor. This study explores the relationships between Cabernet Sauvignon grape volatile composition and wine volatile profiles with the sensory properties of wines. Twenty grape samples were obtained from nine vineyard sites across three vintages and wines vinified from these parcels using controlled winemaking methods. The volatile composition of the grapes were analyzed by SBSE-GCMS, the wines were analyzed by SPME-GCMS, and these data sets were compared to that obtained from the sensory analysis of the wines. Statistical treatment of the data to account for vintage and region effects allowed underlying relationships to be seen between wine sensory attributes and wine or grape volatile components. The observed associations between grape or wine volatile compounds and wine sensory attributes has revealed target compounds and pathways whose levels may reflect the biochemical effects on grape composition by differing growth conditions during berry development and ripening. The compounds identified in this study may be useful grape or wine markers for potential wine sensory characteristics.

  15. Oils; lubricants; paraffin-wax compositions; hydrocarbon condensation products

    Energy Technology Data Exchange (ETDEWEB)

    1934-04-04

    Petroleum hydrocarbons such as gasoline, kerosene, Diesel fuel oil, lubricating-oil, and paraffin wax, and like hydrocarbons such as are obtainable from shale oil and by the hydrogenation of carbonaceous materials, are improved by addition of products obtained by condensing a cyclic hydrocarbon with a saturated dihalogen derivative of an aliphatic hydrocarbon containing less than five carbon atoms. The addition of the condensation products increases the viscosity of the hydrocarbon oils specified, and is particularly useful in the case of lubricating-oils; addition of the condensation products to paraffin wax increases the transparency and adherent properties of the wax, and is useful in the manufacture of moulded articles such as candles; the products may also be used in solid lubricating-compositions.

  16. Oil characterisation: assessment of composition, risks, degradation and remediation potential of total petroleum hydrocarbons in soil

    Energy Technology Data Exchange (ETDEWEB)

    Lookman, R.; Vanermen, G.; Van De Weghe, H.; Gemoets, J. [Vito, Mol (Belgium); Van der Sterren, G.; Alphenaar, A. [TTE, Deventer (Netherlands)

    2005-07-01

    Several methods are available for the characterization of petroleum hydrocarbons. The TPHCWG (Total Petroleum Hydrocarbon Criteria Working Group) developed a method based on a silica column separation of aromatics and aliphatics and a GC-FID subdivision into equivalent-carbon fractions (EC) ('TPH-method'). This method was mainly developed for assessing human risks of oil compounds. Within NOBIS (Dutch Research program Biological In-situ Remediation), another method was developed based upon an equilibrium-experiment of the oil-polluted soil with water (column recirculation), which was further developed by TTE ('TTE-method'). This method uses measured water solubilities of individual oil components and GC-retention times yielding a subdivision of the hydrocarbons into compound classes that are relevant for assessing the remediation potential of the specific oil pollution. In this paper we present results of a research project in which we developed a new method, the 'OK-method' that combines these two procedures and allows a complete characterisation of the oil in terms of composition, (human) risks, volatility, solubility, plume behaviour (migration velocities of the soluble components) and aerobic degradation potential. (authors)

  17. Determination of volatile organic hydrocarbons in water samples by solid-phase dynamic extraction

    Energy Technology Data Exchange (ETDEWEB)

    Jochmann, Maik A.; Schmidt, Torsten C. [Eberhard-Karls-Universitaet Tuebingen, Center for Applied Geoscience (ZAG), Tuebingen (Germany); Chair of Instrumental Analysis, University Duisburg-Essen, Duisburg (Germany); Yuan, Xue [Eberhard-Karls-Universitaet Tuebingen, Center for Applied Geoscience (ZAG), Tuebingen (Germany)

    2007-03-15

    In the present study a headspace solid-phase dynamic extraction method coupled to gas chromatography-mass spectrometry (HS-SPDE-GC/MS) for the trace determination of volatile halogenated hydrocarbons and benzene from groundwater samples was developed and evaluated. As target compounds, benzene as well as 11 chlorinated and brominated hydrocarbons (vinyl chloride, dichloromethane, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, carbon tetrachloride, chloroform, trichloroethylene, tetrachloroethylene, bromoform) of environmental and toxicological concern were included in this study. The analytes were extracted using a SPDE needle device, coated with a poly(dimethylsiloxane) with 10% embedded activated carbon phase (50-{mu}m film thickness and 56-mm film length) and were analyzed by GC/MS in full-scan mode. Parameters that affect the extraction yield such as extraction and desorption temperature, salting-out, extraction and desorption flow rate, extraction volume and desorption volume, the number of extraction cycles, and the pre-desorption time have been evaluated and optimized. The linearity of the HS-SPDE-GC/MS method was established over several orders of magnitude. Method detection limits (MDLs) for the compounds investigated ranged between 12 ng/L for cis-dichloroethylene and trans-dichloroethylene and 870 ng/L for vinyl chloride. The method was thoroughly validated, and the precision at two concentration levels (0.1 mg/L and a concentration 5 times above the MDL) was between 3.1 and 16% for the analytes investigated. SPDE provides high sensitivity, short sample preparation and extraction times and a high sample throughput because of full automation. Finally, the applicability to real environmental samples is shown exemplarily for various groundwater samples from a former waste-oil recycling facility. Groundwater from the site showed a complex contamination with chlorinated volatile organic compounds and aromatic hydrocarbons. (orig.)

  18. Determination of volatile organic hydrocarbons in water samples by solid-phase dynamic extraction.

    Science.gov (United States)

    Jochmann, Maik A; Yuan, Xue; Schmidt, Torsten C

    2007-03-01

    In the present study a headspace solid-phase dynamic extraction method coupled to gas chromatography-mass spectrometry (HS-SPDE-GC/MS) for the trace determination of volatile halogenated hydrocarbons and benzene from groundwater samples was developed and evaluated. As target compounds, benzene as well as 11 chlorinated and brominated hydrocarbons (vinyl chloride, dichloromethane, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, carbon tetrachloride, chloroform, trichloroethylene, tetrachloroethylene, bromoform) of environmental and toxicological concern were included in this study. The analytes were extracted using a SPDE needle device, coated with a poly(dimethylsiloxane) with 10% embedded activated carbon phase (50-microm film thickness and 56-mm film length) and were analyzed by GC/MS in full-scan mode. Parameters that affect the extraction yield such as extraction and desorption temperature, salting-out, extraction and desorption flow rate, extraction volume and desorption volume, the number of extraction cycles, and the pre-desorption time have been evaluated and optimized. The linearity of the HS-SPDE-GC/MS method was established over several orders of magnitude. Method detection limits (MDLs) for the compounds investigated ranged between 12 ng/L for cis-dichloroethylene and trans-dichloroethylene and 870 ng/L for vinyl chloride. The method was thoroughly validated, and the precision at two concentration levels (0.1 mg/L and a concentration 5 times above the MDL) was between 3.1 and 16% for the analytes investigated. SPDE provides high sensitivity, short sample preparation and extraction times and a high sample throughput because of full automation. Finally, the applicability to real environmental samples is shown exemplarily for various groundwater samples from a former waste-oil recycling facility. Groundwater from the site showed a complex contamination with chlorinated volatile organic compounds and aromatic hydrocarbons.

  19. Effect of volatile hydrocarbon fractions on mobility and earthworm uptake of polycyclic aromatic hydrocarbons from soils and soil/lampblack mixtures.

    Science.gov (United States)

    Bogan, Bill W; Beardsley, Kate E; Sullivan, Wendy R; Hayes, Thomas D; Soni, Bhupendra K

    2005-01-01

    Studies were conducted to examine the mobility and bioavailability to earthworms (Eisenia fetida) of priority pollutant polycyclic aromatic hydrocarbons (PAH) in a suite of 11 soils and soil/lampblack mixtures obtained from former manufactured-gas plant sites. Contaminant mobility was assessed using XAD4 resins encapsulated in dialysis tubing, which were exposed to slurried soils for 15 d. These experiments showed that mobility of PAH in the different soils strongly correlated to the levels of volatile hydrocarbons (namely, gasoline- and diesel-range organics [GRO and DRO]) that existed in the soils as co-contaminants. Actual PAH bioavailability (as measured by earthworm PAH concentrations) also appeared to depend on GRO + DRO levels, although this was most evident at high levels of these contaminants. These findings are discussed in view of the effects of dieselrange organics on oil viscosity, assuming that the hydrocarbon contaminants in these soils exist in the form of distinct adsorbed oil phases. This study, therefore, extends correlations between carrier-oil viscosity and dissolved solute bioavailability, previously observed in a number of other in vitro and whole-organism tests (and in bacterial mutagenicity studies in soil), to multicellular organisms inhabiting contaminated-soil systems.

  20. Chemical Diversity in Volatiles of Helichrysum plicatum DC. Subspecies in Turkey

    Directory of Open Access Journals (Sweden)

    Bintuğ Öztürk

    2014-07-01

    Full Text Available In the present work three subspecies of Helichrysum plicatum DC. (Helichrysum plicatum DC. subsp. plicatum, Helichrysum plicatum DC. subsp. polyphillum (Ledeb P.H.Davis & Kupicha and Helichrysum plicatum DC. subsp. isauricum Parolly were investigated for the essential oil chemical compositions. The volatiles were obtained by conventional hydrodistillation of aerial parts and microdistillation of inflorescences. Subsequent gas chromatography (GC-FID and gas chromatography coupled to mass spectrometry (GC/MS revealed chemical diversity in compositions of the volatiles analyzed. A total of 199 compounds were identified representing 73.9-98.3% of the volatiles compositions. High abundance of fatty acids and their esters (24.9-70.8% was detected in the herb volatiles of H. plicatum subsp. polyphyllum and H. plicatum subsp. isauricum. The inflorescences of Helichrysum subspecies were found to be rich in monoterpenes (15.0-93.1%, fatty acids (0.1-36.3% and sesquiterpenes (1.1-25.5%. The inflorescence volatiles of H. plicatum subsp. isauricum were distinguished by predomination of monoterpene hydrocarbons (93.1% with fenchene (88.3% as the major constituent

  1. Air-dust-borne associations of phototrophic and hydrocarbon-utilizing microorganisms: promising consortia in volatile hydrocarbon bioremediation.

    Science.gov (United States)

    Al-Bader, Dhia; Eliyas, Mohamed; Rayan, Rihab; Radwan, Samir

    2012-11-01

    Aquatic and terrestrial associations of phototrophic and heterotrophic microorganisms active in hydrocarbon bioremediation have been described earlier. The question arises: do similar consortia also occur in the atmosphere? Dust samples at the height of 15 m were collected from Kuwait City air, and analyzed microbiologically for phototrophic and heterotrophic hydrocarbon-utilizing microorganisms, which were subsequently characterized according to their 16S rRNA gene sequences. The hydrocarbon utilization potential of the heterotrophs alone, and in association with the phototrophic partners, was measured quantitatively. The chlorophyte Gloeotila sp. and the two cyanobacteria Nostoc commune and Leptolyngbya thermalis were found associated with dust, and (for comparison) the cynobacteria Leptolyngbya sp. and Acaryochloris sp. were isolated from coastal water. All phototrophic cultures harbored oil vapor-utilizing bacteria in the magnitude of 10(5) g(-1). Each phototrophic culture had its unique oil-utilizing bacteria; however, the bacterial composition in Leptolyngbya cultures from air and water was similar. The hydrocarbon-utilizing bacteria were affiliated with Acinetobacter sp., Aeromonas caviae, Alcanivorax jadensis, Bacillus asahii, Bacillus pumilus, Marinobacter aquaeolei, Paenibacillus sp., and Stenotrophomonas maltophilia. The nonaxenic cultures, when used as inocula in batch cultures, attenuated crude oil in light and dark, and in the presence of antibiotics and absence of nitrogenous compounds. Aqueous and diethyl ether extracts from the phototrophic cultures enhanced the growth of the pertinent oil-utilizing bacteria in batch cultures, with oil vapor as a sole carbon source. It was concluded that the airborne microbial associations may be effective in bioremediating atmospheric hydrocarbon pollutants in situ. Like the aquatic and terrestrial habitats, the atmosphere contains dust-borne associations of phototrophic and heterotrophic hydrocarbon

  2. Total Petroleum Hydrocarbon Criteria Working Group (TPHCWG) Field Demonstration Report: IRP Site 4, POL Area, Springfield ANG Base, Springfield, Ohio

    National Research Council Canada - National Science Library

    Reed, Dennis

    2003-01-01

    ...) methodology to compare the approaches. Soil core composites were analyzed for trichloroethylene, gasoline-range organics, volatile petroleum hydrocarbons, benzene, toluene, ethylbenzene, and xylenes...

  3. Composite catalyst for carbon monoxide and hydrocarbon oxidation

    Science.gov (United States)

    Liu, Wei; Flytzani-Stephanopoulos, Maria

    1996-01-01

    A method and composition for the complete oxidation of carbon monoxide and/or hydrocarbon compounds. The method involves reacting the carbon monoxide and/or hydrocarbons with an oxidizing agent in the presence of a metal oxide composite catalyst. The catalyst is prepared by combining fluorite-type oxygen ion conductors with active transition metals. The fluorite oxide, selected from the group consisting of cerium oxide, zirconium oxide, thorium oxide, hafnium oxide, and uranium oxide, and may be doped by alkaline earth and rare earth oxides. The transition metals, selected from the group consisting of molybdnum, copper, cobalt, maganese, nickel, and silver, are used as additives. The atomic ratio of transition metal to fluorite oxide is less than one.

  4. Volatile organic compounds released by blowfly larvae and pupae: new perspectives in forensic entomology.

    Science.gov (United States)

    Frederickx, C; Dekeirsschieter, J; Brostaux, Y; Wathelet, J-P; Verheggen, F J; Haubruge, E

    2012-06-10

    To evaluate postmortem intervals (PMIs), one should take into account the determined age of necrophagous flies present on the cadaver. However, PMI determination needs further improvement, and rapid and accurate approaches have therefore to be developed. While previous studies have focussed on insect cuticular hydrocarbons, here we explore the volatile profile released by larvae and pupae of Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae). We monitored changes in volatile compounds daily, by headspace solid-phase microextraction, followed by gas chromatography-mass spectrometry. Branched and unbranched hydrocarbons, alcohols, esters and acids were identified, and the volatile profile was shown to vary, in both composition and quantity, with the age of the larva/pupa under investigation. We concluded, based on the analysis of the released volatile organic compounds, that it is possible to increase the accuracy of the estimated PMI, through improved estimation of the age of blowflies present on the cadaver. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  5. Distribution of nonionic organic compounds (highly volatile chlorinated hydrocarbons) in the unsaturated zone

    Energy Technology Data Exchange (ETDEWEB)

    Grathwohl, P.

    1988-01-01

    Nonpolar pollutants, e.g. highly volatile chlorinated hydrocarbons (HVCH) are more or less equally distributed among all three soil phases (solids, water, air) in the unsaturated zone. The sorption of HVCH on soil solids depends on the amount and type of organic matter in the soil. For wet material an additional sorption on mineral surfaces can be neglected, since all possible sites for sorption are occupied by water. Provided the partition-coefficients or sorption-constants are known the contamination of the whole system can be evaluated from the pollutant concentration in the soil air; in addition it is possible to estimate a groundwater risk.

  6. Quantitative evaluation of volatile hydrocarbons in post-mortem blood in forensic autopsy cases of fire-related deaths.

    Science.gov (United States)

    Yonemitsu, Kosei; Sasao, Ako; Oshima, Toru; Mimasaka, Sohtaro; Ohtsu, Yuki; Nishitani, Yoko

    2012-04-10

    Volatile hydrocarbons in post-mortem blood from victims of fires were analyzed quantitatively by headspace gas chromatography mass spectrometry. The benzene and styrene concentrations in the blood were positively correlated with the carboxyhemoglobin (CO-Hb) concentration, which is evidence that the deceased inhaled the hydrocarbons and carbon monoxide simultaneously. By contrast, the concentrations of toluene and CO-Hb in the blood were not significantly correlated. This lack of correlation could be explained by two different sources of toluene, with low blood concentrations of toluene arising when the deceased inhaled smoke and high blood concentrations of toluene arising when the deceased inhaled petroleum vapor or other unknown vapors. The quantity of soot deposited in the respiratory tract was classified into four grades (-, 1+, 2+, 3+). The mean CO-Hb concentration in the 1+ soot group was significantly lower than those in the 2+ (ptypes of smoke produced by different materials. For example, petroleum combustion with a limited supply of oxygen, like in a compartment fire, may produce a large volume of dense black smoke that contains a large quantity of soot. Soot deposits in the airways and the blood CO-Hb concentration are basic and essential autopsy findings that are used to investigate fire-related deaths. The quantitative GC-MS analysis of blood volatile hydrocarbons can provide additional useful information on the cause of the fire and the circumstances surrounding the death. In combination, these three findings are useful for the reconstruction of cases. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  7. Compositional Analysis and Antioxidant Activity of Volatile ...

    African Journals Online (AJOL)

    Compositional Analysis and Antioxidant Activity of Volatile. Components of Two Salvia spp. F Forouzin*, R Jamei and R Heidari. Department of Biology, Faculty of Science, Urmia University, West Azerbaijan, Iran. *For correspondence: Email: f_forouzin@yahoo.com, rjamei274@gmail.com, r.heidari@mail.urmia.ac.ir; Tel: ...

  8. Hydrocarbon conversion with an attenuated superactive multimetallic catalytic composite

    International Nuclear Information System (INIS)

    Antos, G.J.

    1981-01-01

    Hydrocarbons are converted by contacting them at hydrocarbon conversion conditions with a novel attenuated superactive multimetallic catalytic composite comprising a combination of a catalytically effective amount of a pyrolyzed rhenium carbonyl component with a porous carrier material containing a uniform dispersion of catalytically effective amounts of a platinum group component, which is maintained in the elemental metallic state during the incorporation and pyrolysis of the rhenium carbonyl component, and of an iron component. In a highly preferred embodiment, this novel catalytic composite also contains a catalytically effective amount of a halogen component. The platinum group component, pyrolyzed rhenium carbonyl component, iron component and optional halogen component are preferably present in the multimetallic catalytic composite in amounts, calculated on an elemental basis, corresponding to about 0.01 to about 2 wt. % platinum group metal, about 0.01 to about 5 wt. % rhenium, about 0.005 to about 4 wt. % iron and about 0.1 to about 5 wt. % halogen. A key feature associated with the preparation of the subject catalytic composite is reaction of a rhenium carbonyl complex with a porous carrier material containing a uniform dispersion of an iron component and of a platinum group component maintained in the elemental state, whereby the interaction of the rhenium moiety with the platinum group moiety is maximized due to the platinophilic (i.e., platinum-seeking) propensities of the carbon monoxide ligands associated with the rhenium reagent. A specific example of the type of hydrocarbon conversion process disclosed herein is a process for the catalytic reforming of a low octane gasoline fraction wherein the gasoline fraction and a hydrogen stream are contacted with the attenuated superactive multimetallic catalytic composite at reforming conditions

  9. Volatile Fuel Hydrocarbons and MTBE in the Environment

    Science.gov (United States)

    Cozzarelli, I. M.; Baehr, A. L.

    2003-12-01

    Petroleum hydrocarbons (hydrocarbons that result from petroleum products such as oil, gasoline, or diesel fuel) are among the most commonly occurring and widely distributed contaminants in the environment. Volatile hydrocarbons are the lighter fraction of the petroleum hydrocarbons and, together with fuel oxygenates, are most often released from crude oil and liquid petroleum products produced from crude oil. The demand for crude oil stems from the world's ever-growing energy need. From 1970 to 1999, primary energy production of the world grew by 76% (Energy Information Administration, 2001), with fossil fuels (crude oil, natural gas, and coal) accounting for ˜85% of all energy produced worldwide (Figure 1). World crude oil production reached a record 68 million barrels (bbl) per day (1.08×1010 L d-1) in 2000. The world's dependence on oil as an energy source clearly is identified as contributing to global warming and worsening air and water quality. (7K)Figure 1. World primary energy production by source from 1970 to 1999 (Energy Information Administration, 2001). Petroleum products are present in Earth's subsurface as solids, liquids, or gases. This chapter presents a summary of the environmental problems and issues related to the use of liquid petroleum, or oil. The focus is on the sources of volatile hydrocarbons and fuel oxygenates and the geochemical behavior of these compounds when they are released into the environment. Although oxygenates currently in commercial use include compounds other than methyl t-butyl ether (MTBE), such as ethanol (ETOH), most of the information presented here focuses on MTBE because of its widespread occurrence. The environmental impact of higher molecular weight hydrocarbons that also originate from petroleum products is described in (Chapter 9.13, Abrajano et al.).Crude oil occurs within the Earth and is a complex mixture of natural compounds composed largely of hydrocarbons containing only hydrogen and carbon atoms. The minor

  10. Field desorption mass spectroscopy monitoring of changes in hydrocarbon type composition during petroleum biodegradation

    International Nuclear Information System (INIS)

    Huesemann, M.H.

    1995-01-01

    A comprehensive petroleum hydrocarbon characterization procedure involving group type separation, boiling point distribution, and hydrocarbon typing by field desorption mass spectroscopy (FDMS) has been developed to quantify changes in hydrocarbon type composition during bioremediation of petroleum-contaminated soils. FDMS is able to quantify the concentration of hundreds of specific hydrocarbon types based on their respective hydrogen deficiency (z-number) and molecular weight (carbon number). Analytical results from two bioremediation experiments involving soil contaminated with crude oil and motor oil indicate that alkanes and two-ring saturates (naphthenes) were readily biodegradable. In addition, low-molecular-weight hydrocarbons generally were biodegraded to a larger extent than those of high molecular weight. More importantly, it was found that the extent of biodegradation of specific hydrocarbon types was comparable between treatments and appeared to be unaffected by the petroleum contaminant source, soil type, or experimental conditions. It was therefore concluded that in these studies the extent of total petroleum hydrocarbon (TPH) biodegradation is primarily affected by the molecular composition of the petroleum hydrocarbons present in the contaminated soil

  11. Polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs) mitigation in the pyrolysis process of waste tires using CO₂ as a reaction medium.

    Science.gov (United States)

    Kwon, Eilhann E; Oh, Jeong-Ik; Kim, Ki-Hyun

    2015-09-01

    Our work reported the CO2-assisted mitigation of PAHs and VOCs in the thermo-chemical process (i.e., pyrolysis). To investigate the pyrolysis of used tires to recover energy and chemical products, the experiments were conducted using a laboratory-scale batch-type reactor. In particular, to examine the influence of the CO2 in pyrolysis of a tire, the pyrolytic products including C1-5-hydrocarbons (HCs), volatile organic carbons (VOCs), and polycyclic aromatic hydrocarbons (PAHs) were evaluated qualitatively by gas chromatography (GC) with mass spectroscopy (MS) as well as with a thermal conductivity detector (TCD). The mass balance of the pyrolytic products under various pyrolytic conditions was established on the basis of their weight fractions of the pyrolytic products. Our experimental work experimentally validated that the amount of gaseous pyrolytic products increased when using CO2 as a pyrolysis medium, while substantially altering the production of pyrolytic oil in absolute content (7.3-17.2%) and in relative composition (including PAHs and VOCs). Thus, the co-feeding of CO2 in the pyrolysis process can be considered an environmentally benign and energy efficient process. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Method and apparatus for removing volatile hydrocarbons from particulate soils

    International Nuclear Information System (INIS)

    Mendenhall, R.L.

    1992-01-01

    This patent describes an apparatus for heating solid particulate mineral compositions. It comprises: a counterflow ratable drum having a first end and an opposite second end, a first portion of the drum extending from the first end for a first length and having a first diameter along the first length, and a second portion of the drum secured to and extending from the first portion to the second end for a second length and having a second diameter along the second length, the second diameter being less than the first diameter, a burner adjacent the first end for introducing and directing hot gases of combustion into the first portion of the drum toward the second end, means for introducing particulate composition into the drum at the second end, means for directing the particulate composition along the drum from the second end toward the first end, and means for recovering composition at the first end, means for removing a gaseous mixture of organic volatiles, gases of combustion and fine particles of the particulate composition adjacent the second drum end, means for separating fine particles of the particulate composition from the gaseous mixture, and means for returning the separated fine particulate composition particles to the first portion of the drum

  13. Process for treating hydrocarbons, etc

    Energy Technology Data Exchange (ETDEWEB)

    1933-09-15

    A process is described for treating simultaneously bituminous substances and hydrocarbon oils for the production of low-boiling hydrocarbons and volatilization of the bituminous substances, characterized by the fact that it consists of heating a current of charge constituted by a mixture of the bituminous substances and hydrocarbon oils, to a high temperature, passing the heated current into a zone of extended reaction where the vapors are separated from the liquid or solid residue to favor transformation of the liquid hydrocarbons and volatilization of the bituminous substances, owing to the utilization of a heating agent carried to a high temperature being brought in contact with the heated charge in order to communicate its heat to the charge, while this later presents itself as relatively fine pellet or in the condition of distinct particles, particularly separated from one another.

  14. Chemical composition of the semi-volatile grains of comet 67P/Churyumov-Gerasimenko

    Science.gov (United States)

    Wurz, Peter; Altwegg, Kathrin; Balsiger, Hans; Berthelier, Jean-Jacques; Bieler, André; Calmonte, Ursina; De Keyser, Johan; Fiethe, Björn; Fuselier, Stefan; Gasc, Sébastien; Gombosi, Tamas; Jäckel, Annette; Korth, Axel; Le Roy, Lena; Mall, Urs; Rème, Henri; Rubin, Martin; Tzou, Chia-Yu

    2017-04-01

    grain is completely evaporated in such an ion source after a few 100 seconds, the RTOF instrument is best suited for the investigation of its chemical composition since several complete mass spectra are recorded during this time. The rate of dust grains recorded in RTOF is small, and we report on the collection and analysis of 9 dust grains during the October 2014 to July 2016 time period. It is estimated that these grains contain about 1E-15 g of volatiles, which would correspond to a grain of the order of 100 nm in size if made up of volatiles alone. We fitted the recorded mass spectra of RTOF with a set of 61 molecules, and their molecular fragments resulting from the ionisation. The major groups of chemical species are hydrocarbons, oxygenated hydrocarbons, nitrogen-bearing molecules, sulphur-bearing molecules, halogenated molecules and others (including water and CO2). About 70% of these grains are depleted in water compared to the comet coma, thus, can be considered as semi-volatile dust grains, and the other about 30% are water grains. The mineral phase of these grains, if there is any, cannot be investigated in these measurements. However, in an earlier investigation the bulk composition of mineral grains on the surface of the comet was inferred from solar wind sputtering of these grains (Wurz et al., 2015). H. Balsiger, K. Altwegg, P. Bochsler, P. Eberhardt, J. Fischer, S. Graf, A. Jäckel, E. Kopp, U. Langer, M. Mildner, J. Müller, T. Riesen, M. Rubin, S. Scherer, P. Wurz, S. Wüthrich, E. Arijs, S. Delanoye, J. De Keyser, E. Neefs, D. Nevejans, H. Rème, C. Aoustin, C. Mazelle, J.-L. Médale, J.A. Sauvaud, J.-J. Berthelier, J.-L. Ber-taux, L. Duvet, J.-M. Illiano, S.A. Fuselier, A.G. Ghielmetti, T. Magoncelli, E.G. Shelley, A. Korth, K. Heerlein, H. Lauche, S. Livi, A. Loose, U. Mall, B. Wilken, F. Gliem, B. Fiethe, T.I. Gombosi, B. Block, G.R. Carignan, L.A. Fisk, J.H. Waite, D.T. Young, and H. Wollnik, ROSINA - Rosetta Orbiter Spectrometer for Ion and

  15. ISOTOPIC (14C) AND CHEMICAL COMPOSITION OF ATMOSPHERIC VOLATILE ORGANIC COMPOUND FRACTIONS - PRECURSORS TO OZONE FORMATION

    Science.gov (United States)

    Atmospheric volatile organic compounds (VOCs) are an important factor in the production of ozone near ground level [3]. Many hydrocarbons originate from auto exhaust. However, a number of VOCs, e.g., isoprene, are known to be natural in origin. To develop reliable models for un...

  16. Biological activity and phytochemical composition of the volatile oils from basilicum polystachyon

    International Nuclear Information System (INIS)

    Cui, H.X.; Cheng, F.R.

    2017-01-01

    This paper extracted and determined the chemical components of the volatile oil in Basilicum polystachyon, and measured and evaluated the bioactivity of the volatile oil in Basilicum polystachyon. The oils were obtained by hydrodistillation, and their chemical compositions were separated and determined by gas chromatography-mass spectrometry (GC-MS). Minimum inhibitory concentrations (MIC) were determined by using the 8 kinds of plant pathogenic fungi. The free radicals scavenging activity of its volatile oil for the IC/sub 50/ were investigated by using Trolox as the comparison and cytotoxicity by brine shrimp lethal bioassay. The results show that 64 constituents of oils isolated respectively from Basilicum polystachyon were identified. The appraised components take up 99.75% of the total peak area. The main composition of the volatile oil is sesquiterpenoids and monoterpene. The results exhibit that the volatile oil in Basilicum polystachyon has very strong bioactivity of antimicrobial, antioxidant and cytotoxicity. These results provided the reference for further understanding the chemical components and its bioactivity of this aromatic plant as well as its further development. (author)

  17. Hydrocarbons and air pollution

    International Nuclear Information System (INIS)

    Herz, O.

    1992-01-01

    This paper shows the influence of hydrocarbons vapors, emitted by transports or by volatile solvents using, on air pollution. Hydrocarbons are the principal precursors of photochemical pollution. After a brief introduction on atmospheric chemistry and photochemical reactions, the author describes the french prevention program against hydrocarbons emissions. In the last chapter, informations on international or european community programs for photochemical pollution study are given. 5 figs., 10 tabs

  18. Volatile flavor compounds in yogurt: a review.

    Science.gov (United States)

    Cheng, Hefa

    2010-11-01

    Considerable knowledge has been accumulated on the volatile compounds contributing to the aroma and flavor of yogurt. This review outlines the production of the major flavor compounds in yogurt fermentation and the analysis techniques, both instrumental and sensory, for quantifying the volatile compounds in yogurt. The volatile compounds that have been identified in plain yogurt are summarized, with the few key aroma compounds described in detail. Most flavor compounds in yogurt are produced from lipolysis of milkfat and microbiological transformations of lactose and citrate. More than 100 volatiles, including carbonyl compounds, alcohols, acids, esters, hydrocarbons, aromatic compounds, sulfur-containing compounds, and heterocyclic compounds, are found in yogurt at low to trace concentrations. Besides lactic acid, acetaldehyde, diacetyl, acetoin, acetone, and 2-butanone contribute most to the typical aroma and flavor of yogurt. Extended storage of yogurt causes off-flavor development, which is mainly attributed to the production of undesired aldehydes and fatty acids during lipid oxidation. Further work on studying the volatile flavor compounds-matrix interactions, flavor release mechanisms, and the synergistic effect of flavor compounds, and on correlating the sensory properties of yogurt with the compositions of volatile flavor compounds are needed to fully elucidate yogurt aroma and flavor.

  19. Endogenous Lunar Volatiles

    Science.gov (United States)

    McCubbin, F. M.; Liu, Y.; Barnes, J. J.; Boyce, J. W.; Day, J. M. D.; Elardo, S. M.; Hui, H.; Magna, T.; Ni, P.; Tartese, R.; hide

    2017-01-01

    The chapter will begin with an introduction that defines magmatic volatiles (e.g., H, F, Cl, S) versus geochemical volatiles (e.g., K, Rb, Zn). We will discuss our approach of understanding both types of volatiles in lunar samples and lay the ground work for how we will determine the overall volatile budget of the Moon. We will then discuss the importance of endogenous volatiles in shaping the "Newer Views of the Moon", specifically how endogenous volatiles feed forward into processes such as the origin of the Moon, magmatic differentiation, volcanism, and secondary processes during surface and crustal interactions. After the introduction, we will include a re-view/synthesis on the current state of 1) apatite compositions (volatile abundances and isotopic compositions); 2) nominally anhydrous mineral phases (moderately to highly volatile); 3) volatile (moderately to highly volatile) abundances in and isotopic compositions of lunar pyroclastic glass beads; 4) volatile (moderately to highly volatile) abundances in and isotopic compositions of lunar basalts; 5) volatile (moderately to highly volatile) abundances in and isotopic compositions of melt inclusions; and finally 6) experimental constraints on mineral-melt partitioning of moderately to highly volatile elements under lunar conditions. We anticipate that each section will summarize results since 2007 and focus on new results published since the 2015 Am Min review paper on lunar volatiles [9]. The next section will discuss how to use sample abundances of volatiles to understand the source region and potential caveats in estimating source abundances of volatiles. The following section will include our best estimates of volatile abundances and isotopic compositions (where permitted by available data) for each volatile element of interest in a number of important lunar reservoirs, including the crust, mantle, KREEP, and bulk Moon. The final section of the chapter will focus upon future work, outstanding questions

  20. Detection of volatile hydrocarbons and 2-dodecyl-cyclobutanone in irradiated Camembert. Nachweise von fluechtigen Kohlenwasserstoffen und 2-Dodecylcyclobutanon in bestrahltem Camembert

    Energy Technology Data Exchange (ETDEWEB)

    Spiegelberg, A. (Fachgebiet Lebensmittelbestrahlung, Bundesgesundheitsamt, Berlin (Germany)); Estendorfer, S. (Landesuntersuchungsamt fuer das Gesundheitswesen Suedbayern, Oberschleissheim (Germany)); Schulzki, G. (Fachgebiet Lebensmittelbestrahlung, Bundesgesundheitsamt, Berlin (Germany)); Helle, N. (Fachgebiet Lebensmittelbestrahlung, Bundesgesundheitsamt, Berlin (Germany)); Boegl, K.W. (Fachgebietsgruppe Lebensmittel- und Arzneimittelbestrahlung, Alternativverfahren, Bundesgesundheitsamt, Berlin (Germany)); Schreiber, G.A. (Fachgebiet Lebensmittelbestrahlung, Bundesgesundheitsamt, Berlin (Germany))

    1993-09-01

    The same methods which are used to detect radiation treatment of meat - the detection of volatile hydrocarbons and 2-alkylcyclobutanones - were successfully applied to identify irradiated Camembert (0.5 until 3 kGy) in examinations performed independently by the ''Landesuntersuchungsamt fuer das Gesundheitswesen Suedbayern'' (LUA) and by the Federal Health Office (BGA). (orig.)

  1. CHANGES IN VOLATILE COMPOSITION OF KRALJEVINA WINES BY CONTROLLED MALOLACTIC FERMENTATION

    Directory of Open Access Journals (Sweden)

    Ana JEROMEL

    2008-11-01

    Full Text Available The effect of malolactic fermentation (MLF on the volatile composition of white wines made from autochtonous grape variety Kraljevina was studied by inoculation with selected lactic acid bacteria. At the end of malolactic fermentation, after the decomposition of the malic acid present in wine the non volatile compounds were analyzed by HPLC, while volatile compounds were analyzed by gas chromatography. All wines were also sensory analyzed. Results showed changes in acetaldehyde, some higher alcohols, ethyl esters, free and bound monoterpenes and some organic acids that contribute to enhance the sensory properties and quality of Kraljevina wines that underwent malolactic fermentation.

  2. A study on the composition of off-odor volatiles in irradiated pork

    International Nuclear Information System (INIS)

    Lin Ruotai; Geng Shengrong; Zhang Jinmu; Chen Yuxia; Liu Yangmin; Wang Liping; Wang Hong; Xu Ying; Yao Side

    2006-01-01

    The purpose of this study was to lay a foundation on generation mechanisms and removal method of off-odor of irradiated meat products. Vacuum-package and refrigerated raw pork samples were irradiated with 60 Co γ-rays. Off-odor volatiles from the irradiated pork samples were taken in by a vacuum system and were collected by a cooled vial in liquid nitrogen. At the same time, the source of off-odor generation was investigated. Main compositions of off-odor volatiles of the irradiated pork were analyzed with gas chromatograph mass spectrometry (GC-MS). The results showed that main compositions of the off-odor volatiles were dimethyl disulfide, dimethyl sulfide, dimethyl trisulfide, methanethiol and S-methyl thioacetate, and the off-odor volatiles came from sulfide-containing amino acid and thiamin of the irradiated pork. Sulfide-containing compounds increased with the dose in the range of 0-3 kGy, and decreased with the refrigeration time, but changed from different kinds of the package. The non-irradiated samples, however, contained just a little sulfide-containing compounds of dimethyl sulfide and vangardbt. (authors)

  3. Discriminative stimulus effects of inhaled 1,1,1-trichloroethane in mice: comparison to other hydrocarbon vapors and volatile anesthetics.

    Science.gov (United States)

    Shelton, Keith L

    2009-04-01

    Because the toxicity of many inhalants precludes evaluation in humans, drug discrimination, an animal model of subjective effects, can be used to gain insights on their poorly understood abuse-related effects. The purpose of the present study was to train a prototypic inhalant that has known abuse liability, 1,1,1-trichloroethane (TCE), as a discriminative stimulus in mice, and compare it to other classes of inhalants. Eight B6SJLF1/J mice were trained to discriminate 10 min of exposure to 12,000 ppm inhaled TCE vapor from air and seven mice were trained to discriminate 4,000 ppm TCE from air. Tests were then conducted to characterize the discriminative stimulus of TCE and to compare it to representative aromatic and chlorinated hydrocarbon vapors, volatile halogenated anesthetics as well as an odorant compound. Only the 12,000 ppm TCE versus the air discrimination group exhibited sufficient discrimination accuracy for substitution testing. TCE vapor concentration- and exposure time-dependently substituted for the 12,000 ppm TCE vapor training stimulus. Full substitution was produced by trichloroethylene, toluene, enflurane, and sevoflurane. Varying degrees of partial substitution were produced by the other volatile test compounds. The odorant, 2-butanol, did not produce any substitution for TCE. The discriminative stimulus effects of TCE are shared fully or partially by chlorinated and aromatic hydrocarbons as well as by halogenated volatile anesthetics. However, these compounds can be differentiated from TCE both quantitatively and qualitatively. It appears that the degree of similarity is not solely a function of chemical classification but may also be dependent upon the neurochemical effects of the individual compounds.

  4. Heating on the volatile composition and sensory aspects of extra-virgin olive oil

    Directory of Open Access Journals (Sweden)

    Cleiton Antônio Nunes

    2013-12-01

    Full Text Available The main ways by which extra-virgin olive oil is consumed include direct application on salads or as an ingredient in sauces, but it is also been used by some for cooking, including frying and baking. However, it has been reported that under heat stress, some nonglyceridic components of olive oil are degraded. So, the effect of heating (at 50, 100, 150, and 200 °C for 2 h on the volatile composition and sensory aspects of extra-virgin olive oil were evaluated. Heating altered the volatile composition of extra-virgin olive oil, mainly at higher temperatures (above 150 °C. The main modifications were related to the formation of large amounts of oxidized compounds, particularly large chain aldehydes. Sensory aspects were also altered when the oil was heated to higher temperatures, which might have occurred because of color alterations and mainly changes in the volatile composition of the oil.

  5. Petroleum environmental research forum field study on biofilters for control of volatile hydrocarbons

    International Nuclear Information System (INIS)

    Leson, G.; Smith, B.J.

    1997-01-01

    A field study on the treatment of volatile petroleum hydrocarbons (PHC) by biofiltration was conducted by the Petroleum Environmental Research Forum (PERF) between 1992 and 1994. Its objective was to assess the technical, regulatory, and economic feasibility of biofiltration for off-gases from petroleum processing and soil remediation equipment. It involved three small-scale biofilters provided by US vendors, treating off-gas from two soil vapor extraction sites and a source of refinery wastewater. Comprehensive monitoring of biofilter operating parameters and performance was conducted. Typically more than 95% of aromatic compounds such as benzene, and odorous reduced sulfur compounds can be removed at residence times of one minute or less, while removal of more than 70% of light aliphatics will require residence times of several minutes, and will thus require correspondingly large filter volumes and higher capital expenditure. The high percentage removal of aromatic hazardous air pollutants (HAP) and odors can generally be accomplished at comparatively short residence times while the need for high-percentage removal, particular of light aliphatics ( 5 ) will generally render biofiltration noncompetitive. Finally, a preliminary economic comparison of biofilters and established control technologies suggested that biofiltration may, for a representative design case involving off-gas from a refinery wastewater treatment operation, offer considerable savings in total cost of air pollution control for petroleum hydrocarbon streams if regulations require the control of aromatic HAP or odors

  6. Chlorination of antimony and its volatilization treatment of waste antimony-uranium composite oxide catalyst

    International Nuclear Information System (INIS)

    Sawada, K.; Enokida, Y.

    2011-01-01

    For the waste antimony-uranium composite oxide catalyst, the chlorination of antimony and its volatilization treatment were proposed, and evaluated using hydrogen chloride gas at 873-1173 K. During the treatment, the weight loss of the composite oxide sample, which resulted from the volatilization of antimony, was confirmed. An X-ray diffraction analysis showed that uranium oxide, U 3 O 8 , was formed during the reaction. After the treatment at 1173 K for 1 h, almost all the uranium contained in the waste catalyst was dissolved by a 3 M nitric acid solution at 353 K within 10 min, although that of the non-treated catalyst was less than 0.1%. It was found that the chlorination and volatilization treatment was effective to separate antimony from the composite oxide catalyst and change uranium into its removable form. (orig.)

  7. Effects of Methyl Jasmonate on the Composition of Volatile Compounds in Pyropia yezoensis

    Science.gov (United States)

    He, Lihong; Wang, Liang; Wang, Linfang; Shen, Songdong

    2018-04-01

    Volatile organic compounds in marine algae have been reported to comprise characteristic flavor of algae and play an important role in their growth, development and defensive response. Yet their biogeneration remain largely unknown. Here we studied the composition of volatile compouds in Pyropia yezoensis and their variations in response to methyl jasmonate (MeJA) and diethyldithiocarbamic acid (DIECA) treatment using gas chromatography-mass spectrometry (GC-MS). A total of 44 compounds belonging to the following chemical classes (n) were identified, including aldehydes (11), alcohols (8), acids and esters (6), alkanes (5), ketones (5), alkenes (3), and S- or N-containing miscellaneous compounds (6). External treatment with plant hormone MeJA increased the content of 1-dodecanol, 4-heptenal, and 2-propenoic acid-2-methyl dodecylester, but decreased the content of phytol, 3-heptadecene, 2-pentadecanone, and isophytol. When pretreated with DIECA, an inhibitor of the octadecanoid pathway leading to the biosynthesis of endogeneous jasmonates and some secondary metabolites, phytol and isophytol were increased, while 4-heptenal, 1-dodecanol, and 2-propenoic acid-2-methyl dodecylester were decreased, both of which were negatively correlated with their variations under MeJA treatment. Collectively, these results suggest that MeJA does affect the volatile composition of P. yezoensis, and the octadecanoid pathway together with endogenous jasmonate pathway may be involved in the biosynthesis of volatile compounds, thereby providing some preliminary envision on the composition and biogeneration of volatile compounds in P. yezoensis.

  8. Distribution of volatile liquid hydrocarbons in the vicinity of power/desalination plants in Kuwait

    International Nuclear Information System (INIS)

    Saeed, T.; Khordagui, H; AI-Bloushi, A.

    1999-01-01

    Volatile liquid hydrocarbons (VLHs) represent some 40% of crude oil and are considered to be the most toxic compounds of petroleum other than the carcinogenic polycyclic aromatic hydrocarbons. The distribution of these compounds in Kuwait's coastal waters in the vicinity and at the inlets of power plants was assessed. About 200 samples were collected from selected sampling stations over the four seasons. The VLHs in the samples were concentrated using Grob's closed-loop technique and analysed by GC using FID and confirmed by GC/MS. The results showed that VLHs were ubiquitous in the coastal water of Kuwait. The detected levels (ranged from 307 to 7882 ng/l in Kuwait Bay and from 331 to 5017 ng/l in the south) were comparable to the levels found in other parts of the world and were not alarming. However, the spotty higher levels encountered gave reason for some concern. Benzenoids (originating from petroleum) predominated, representing roughly 70% of the total VLHs. The levels were relatively low at the intake of the power plant located in the Kuwait Bay (annual average 677 ng/l) while higher levels (annual average 3006 ng/l) were encountered at the intake of the plant located at the south of oil the loading terminals and refineries. (author)

  9. A comparison of the C{sub 2}-C{sub 9} hydrocarbon compositions of vehicle fuels and urban air in Dublin, Ireland

    Energy Technology Data Exchange (ETDEWEB)

    Broderick, B M; Marnane, I S [Trinity College, Dublin (Ireland). Dept. of Civil, Structural and Environmental Engineering

    2002-07-01

    Hourly roadside hydrocarbon concentrations were measured over a six-week period at a heavily trafficked junction in Dublin city centre. Samples of ten typical leaded and unleaded petrol fuels used in Irish vehicles were also collected and their hydrocarbon compositions determined. The measured ambient hydrocarbon concentrations are presented, as are the properties of each of the analysed fuels. Comparison of the ambient hydrocarbon concentrations and the fuel hydrocarbon composition reveals a strong correlation for most hydrocarbons, except those compounds that were wholly combustion derived (i.e. not present in the fuel). Different characteristics were noted for aromatics, alkanes and alkenes. The comparison of roadside ambient air and fuel hydrocarbon content agrees well with other studies that have compared fuel content and exhaust composition. The relative impacts of exhaust and evaporative emissions on roadside hydrocarbon concentrations are apparent. (Author)

  10. Distilling hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Bataafsche, N V; de Brey, J H.C.

    1918-10-30

    Hydrocarbons containing a very volatile constituent and less volatile constituents, such as casing-head gases, still gases from the distillation of crude petroleum and bituminous shale are separated into their constituents by rectification under pressure; a pressure of 20 atmospheres and limiting temperatures of 150/sup 0/C and 40/sup 0/C are mentioned as suitable. The mixture may be subjected to a preliminary treatment consisting in heating to a temperature below the maximum rectification temperature at a pressure greater than that proposed to be used in the rectification.

  11. PERUBAHAN KOMPONEN VOLATIL SELAMA FERMENTASI KECAP [Change Volatile Components During Soy Sauce Fermentation

    Directory of Open Access Journals (Sweden)

    Anton Apriyantono1

    2004-08-01

    Full Text Available A study has been conducted to investigate changes of volatile components during soy sauce fermentation. During the fermentation, many volatile components produced may contribute to soy sauce flavor. THe volatile identified by GC-MS werw classified into hydrocarbon (15, alcohol (15, aldehyde (14, ester (14, ketone (9, benzene derivative (11, fatty acid (9, furan (5, terpenoid (18, pyrazine (3, thiazole (1, pyridine (1 and sulfur containing compound (2.Concentration of compounds found in almost all fermentation steps, such as hexanal and benzaldehyde did. These compounds may be derived from raw soybean, since they were all present in raw soybean and their concentration did not change during fermentation. Concentration of palmitic acid and benzeneacetaldehyde, in general, increased during all fermentation steps. They are probably derived from lipid degradation or microorganism activities. Concentrations of some fatty acids, esters and hydrocarbons, such as linoleic acid, methyl palmitate and heptadecane increased during salt fermentation only. Concentration of some other compounds, such as 2,4 decadienal decreased or undetected during fermentation.The absence of some volatile compounds, e.g. (E-nerolidol and (E,E-famesol in boiled soybean which were previously present in raw soybean may be due to evaporation of these compounds during boiling. Some volatile compounds such as, methyl heptadecanoate and few aromatic alcohols are likely derived from Aspergillus sojae, since these compounds were identified only in 0 day koji

  12. High pressure treatments accelerate changes in volatile composition of sulphur dioxide-free wine during bottle storage.

    Science.gov (United States)

    Santos, Mickael C; Nunes, Cláudia; Rocha, M Angélica M; Rodrigues, Ana; Rocha, Sílvia M; Saraiva, Jorge A; Coimbra, Manuel A

    2015-12-01

    The impact of high hydrostatic pressure (HHP) treatments on volatile composition of sulphur dioxide-free wines during bottle storage was studied. For this purpose, white and red wines were produced without sulphur dioxide (SO2) and, at the end of the alcoholic fermentation, the wines were pressurised at 500 MPa and 425 MPa for 5 min. Wine with 40 ppm of SO2 and a wine without a preservation treatment were used as controls. More than 160 volatile compounds, distributed over 12 chemical groups, were identified in the wines by an advanced gas chromatography technique. The pressurised wines contained a higher content of furans, aldehydes, ketones, and acetals, compared with unpressurised wines after 9 months of storage. The changes in the volatile composition indicate that HHP treatments accelerated the Maillard reaction, and alcohol and fatty acid oxidation, leading to wines with a volatile composition similar to those of faster aged and/or thermally treated wines. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. The effect of composition on volatility from a copper alloy

    International Nuclear Information System (INIS)

    McCarthy, K.A.; Smolik, G.R.; Wallace, R.S.

    1994-01-01

    During a Loss of Coolant Accident (LOCA) activated structural material can be mobilized through oxidation. Information on how much material is mobilized in an accident is necessary for performing safety assessments of fusion reactor designs. The Fusion Safety Program at the Idaho National Engineering Laboratory has an experimental program to measure mobilized mass as a function of temperature for various oxidizing environments. Materials studied have included beryllium (important because of its toxicity), copper alloys, a niobium alloy, PCA and HT-9 steel, tungsten (pure and an alloy), and a vanadium alloy. Some materials undergo a significant change in composition during irradiation. An example of this is copper (a candidate for the ITER first wall, divertor substrate, and various instrumentation probes and antennas), which can have as much as 1 wt% zinc due to transmutation. Additionally, as the design for ITER evolves, a slightly different copper alloy may be selected. Compositional changes may affect the extent that various elements are volatilized due to such mechanisms as diffusion through the alloy, and penetration and release from oxide layers formed on the material. To accurately calculate offsite doses for various irradiation scenarios, one must understand the effect of composition on volatility

  14. Volatile Composition of Some Cultivated and Wild Culinary-Medicinal Mushrooms from Hungary.

    Science.gov (United States)

    Csóka, Mariann; Geosel, Andras; Amtmann, Maria; Korany, Kornel

    2017-01-01

    The volatile constituents of the fruiting bodies of 4 culinary-medicinal mushroom species (Agaricus bisporus, Boletus edulis, Cantharellus cibarius, and Hericium erinaceus) from Hungary were examined to review their aroma composition. Simultaneous distillation/extraction was applied to extract volatile compounds from fungi, and the values were measured with gas chromatography--mass spectrometry. Although the fragrances of fungi are not as characteristic as those of spices, several groups of volatile compounds have been found in mushrooms. The number of identified components ranged between 61 and 100, with a high ratio of 8-carbon volatiles generally occurring in fungi. Beyond common properties, individual attributes have been identified as well: an outstanding ratio of benzene compounds in champignons, numerous N-containing volatiles in boletes, carotenoid degradation products in chanterelles, and esters and fatty acids with a high carbon number in the lion's mane mushroom. The identification of these characteristic fragrance constituents can be very important in differentiating between species and confirming their presence in mushroom products.

  15. Characterization of cyanobacterial hydrocarbon composition and distribution of biosynthetic pathways.

    Directory of Open Access Journals (Sweden)

    R Cameron Coates

    Full Text Available Cyanobacteria possess the unique capacity to naturally produce hydrocarbons from fatty acids. Hydrocarbon compositions of thirty-two strains of cyanobacteria were characterized to reveal novel structural features and insights into hydrocarbon biosynthesis in cyanobacteria. This investigation revealed new double bond (2- and 3-heptadecene and methyl group positions (3-, 4- and 5-methylheptadecane for a variety of strains. Additionally, results from this study and literature reports indicate that hydrocarbon production is a universal phenomenon in cyanobacteria. All cyanobacteria possess the capacity to produce hydrocarbons from fatty acids yet not all accomplish this through the same metabolic pathway. One pathway comprises a two-step conversion of fatty acids first to fatty aldehydes and then alkanes that involves a fatty acyl ACP reductase (FAAR and aldehyde deformylating oxygenase (ADO. The second involves a polyketide synthase (PKS pathway that first elongates the acyl chain followed by decarboxylation to produce a terminal alkene (olefin synthase, OLS. Sixty-one strains possessing the FAAR/ADO pathway and twelve strains possessing the OLS pathway were newly identified through bioinformatic analyses. Strains possessing the OLS pathway formed a cohesive phylogenetic clade with the exception of three Moorea strains and Leptolyngbya sp. PCC 6406 which may have acquired the OLS pathway via horizontal gene transfer. Hydrocarbon pathways were identified in one-hundred-forty-two strains of cyanobacteria over a broad phylogenetic range and there were no instances where both the FAAR/ADO and the OLS pathways were found together in the same genome, suggesting an unknown selective pressure maintains one or the other pathway, but not both.

  16. [Composition of the electrocautery smoke: integrative literature review].

    Science.gov (United States)

    Tramontini, Cibele Cristina; Galvão, Cristina Maria; Claudio, Caroline Vieira; Ribeiro, Renata Perfeito; Martins, Júlia Trevisan

    2016-02-01

    To identify the composition of the smoke produced by electrocautery use during surgery. Integrative review with search for primary studies conducted in the databases of the US National Library of Medicine National Institutes of Health, Cumulative Index to Nursing and Allied Health Literature, and Latin American and Caribbean Health Sciences, covering the studies published between 2004 and 2014. The final sample consisted of 14 studies grouped into three categories, namely; polycyclic aromatic hydrocarbons, volatile compounds and volatile organic compounds. There is scientific evidence that electrocautery smoke has volatile toxic, carcinogenic and mutagenic compounds, and its inhalation constitutes a potential chemical risk to the health of workers involved in surgeries.

  17. The leaf volatile constituents of Isatis tinctoria by Solid-Phase Microextraction and Gas chromatography/Mass Spectrometry.

    Science.gov (United States)

    Condurso, Cettina; Verzera, Antonella; Romeo, Vincenza; Ziino, Marisa; Trozzi, Alessandra; Ragusa, Salvatore

    2006-08-01

    The leaf volatile constituents of Isatis tinctoria L. (Brassicaceae) have been studied by Solid-Phase Microextraction and Gas chromatography/Mass Spectrometry (SPME/GC-MS). Seventy components were fully characterized by mass spectra, linear retention indices, and injection of standards; the average composition (ppm) as single components and classes of substances is reported. Aliphatic hydrocarbons, acids, alcohols, aldehydes and esters, aromatic aldehydes, esters and ethers, furans, isothiocyanates and thiocyanates, sulfurated compounds, nitriles, terpenes and sesquiterpenes were identified. Leaf volatiles in Isatis tinctoria L. were characterized by a high amount of isothiocyanates which accounted for about 40 % of the total volatile fraction. Isothiocyanates are important and characteristic flavour compounds in Brassica vegetables and the cancer chemo-protective attributes are recently responsible for their growing interest.

  18. [Compositions and residual properties of petroleum hydrocarbon in contaminated soil of the oilfields].

    Science.gov (United States)

    Hu, Di; Li, Chuan; Dong, Qian-Qian; Li, Li-Ming; Li, Guang-He

    2014-01-01

    The aims of this study were to determine the compositions and residual properties of petroleum hydrocarbon in soil, as well as to identify the source and weathering degree of the pollution. A total of 5 producing wells in Gudao and Hekou oil producing region of Shengli oilfields were analyzed. More than 50 individual target compounds including straight-and branched-chain alkanes( n-alkanes, pristine and phytane) and polycyclic aromatic hydrocarbons (PAHs) in soil samples and crude oil were determined by gas chromatography-mass spectrometry (GC-MS). The percentages of chain alkanes and PAHs in total solvent extractable matters(TSEM) of soil samples were both much lower than those in the crude oil samples. The compositions of petroleum hydrocarbon in soil samples differed from those in crude oil, which indicated the n-alkanes with carbon numbers contaminated soils, the relationship between the index and petroleum hydrocarbon compounds was analyzed using principal component analysis (PCA). The results showed that the n-alkanes with carbon numbers > 33 and the PAHs with rings between 3 and 5 were much harder to degrade. PCA of 4 indexes for source identification revealed more than 50% of the soil samples were polluted by crude oil, which needs more attention during remediation.

  19. Aromatic hydrocarbons

    International Nuclear Information System (INIS)

    Roder, M.

    1985-01-01

    Papers dealing with radiolysis of aromatic hydrocarbons of different composition (from benzene to terphenyls and hydrocarbons with condensed rings) as well as their mixtures (with alkanes, alkenes, other aromatic hydrocarbons) are reviewed. High radiation stability of aromatic hydrocarbons in condensed phases associated with peculiarities of molecular structure of compounds is underlined. Mechanisms of radiolytic processes, vaues of product yields are considered

  20. 29 CFR 1910.1002 - Coal tar pitch volatiles; interpretation of term.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 6 2010-07-01 2010-07-01 false Coal tar pitch volatiles; interpretation of term. 1910.1002... Hazardous Substances § 1910.1002 Coal tar pitch volatiles; interpretation of term. As used in § 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from the...

  1. Influence of nonylphenol on the fatty acids and hydrocarbon composition of aquatic plants

    Directory of Open Access Journals (Sweden)

    І. О. Osinna

    2009-11-01

    Full Text Available Composition of surface lipids of aquatic plants Acorus calamus L., Typha latifolia L. and Carex acuta L. was investigated under the influence of nonylphenol strong solution. Experimental plants showed some significant changes in the surface lipids composition in comparison with a control. Change in the fatty acids composition, decrease of hydrocarbons content and biosynthetical disorder in the elongation processes of some certain components were revealed.

  2. Enhanced non-volatile and updatable holography using a polymer composite system.

    Science.gov (United States)

    Wu, Pengfei; Sun, Sam Q; Baig, Sarfaraz; Wang, Michael R

    2012-03-12

    Updatable holography is considered as the ultimate technique for true 3D information recording and display. However, there is no practical solution to preserve the required features of both non-volatility and reversibility which conflict with each other when the reading has the same wavelength as the recording. We demonstrate a non-volatile and updatable holographic approach by exploiting new features of molecular transformations in a polymer recording system. In addition, by using a new composite recording film containing photo-reconfigurable liquid-crystal (LC) polymer, the holographic recording is enhanced due to the collective reorientation of LC molecules around the reconfigured polymer chains.

  3. Wintertime aerosol chemical composition, volatility, and spatial variability in the greater London area

    Directory of Open Access Journals (Sweden)

    L. Xu

    2016-02-01

    Full Text Available The composition of PM1 (particulate matter with diameter less than 1 µm in the greater London area was characterized during the Clean Air for London (ClearfLo project in winter 2012. Two high-resolution time-of-flight aerosol mass spectrometers (HR-ToF-AMS were deployed at a rural site (Detling, Kent and an urban site (North Kensington, London. The simultaneous and high-temporal resolution measurements at the two sites provide a unique opportunity to investigate the spatial distribution of PM1. We find that the organic aerosol (OA concentration is comparable between the rural and urban sites, but the contribution from different sources is distinctly different between the two sites. The concentration of solid fuel OA at the urban site is about twice as high as at the rural site, due to elevated domestic heating in the urban area. While the concentrations of oxygenated OA (OOA are well-correlated between the two sites, the OOA concentration at the rural site is almost twice that of the urban site. At the rural site, more than 70 % of the carbon in OOA is estimated to be non-fossil, which suggests that OOA is likely related to aged biomass burning considering the small amount of biogenic SOA in winter. Thus, it is possible that the biomass burning OA contributes a larger fraction of ambient OA in wintertime than what previous field studies have suggested. A suite of instruments was deployed downstream of a thermal denuder (TD to investigate the volatility of PM1 species at the rural Detling site. After heating at 250 °C in the TD, 40 % of the residual mass is OA, indicating the presence of non-volatile organics in the aerosol. Although the OA associated with refractory black carbon (rBC; measured by a soot-particle aerosol mass spectrometer only accounts for < 10 % of the total OA (measured by a HR-ToF-AMS at 250 °C, the two measurements are well-correlated, suggesting that the non-volatile organics have similar sources or have

  4. Composition of the electrocautery smoke: integrative literature review

    Directory of Open Access Journals (Sweden)

    Cibele Cristina Tramontini

    2016-02-01

    Full Text Available Abstract OBJECTIVE To identify the composition of the smoke produced by electrocautery use during surgery. METHOD Integrative review with search for primary studies conducted in the databases of the US National Library of Medicine National Institutes of Health, Cumulative Index to Nursing and Allied Health Literature, and Latin American and Caribbean Health Sciences, covering the studies published between 2004 and 2014. RESULTS The final sample consisted of 14 studies grouped into three categories, namely; polycyclic aromatic hydrocarbons, volatile compounds and volatile organic compounds. CONCLUSION There is scientific evidence that electrocautery smoke has volatile toxic, carcinogenic and mutagenic compounds, and its inhalation constitutes a potential chemical risk to the health of workers involved in surgeries.

  5. Low-concentration tailing and subsequent quicklime-enhanced remediation of volatile chlorinated hydrocarbon-contaminated soils by mechanical soil aeration.

    Science.gov (United States)

    Ma, Yan; Du, Xiaoming; Shi, Yi; Xu, Zhu; Fang, Jidun; Li, Zheng; Li, Fasheng

    2015-02-01

    Mechanical soil aeration has long been regarded as an effective ex-situ remediation technique and as suitable for remediation of large-scale sites contaminated by volatile organic compounds (VOCs) at low cost. However, it has been reported that the removal efficiency of VOCs from soil is relatively low in the late stages of remediation, in association with tailing. Tailing may extend the remediation time required; moreover, it typically results in the presence of contaminants residues at levels far exceeding regulations. In this context, the present study aimed to discuss the tailing that occurs during the process of remediation of soils contaminated artificially with volatile chlorinated hydrocarbons (VCHs) and to assess possible quicklime-enhanced removal mechanisms. The results revealed the following conclusions. First, temperature and aeration rate can be important controls on both the timing of appearance of tailing and the levels of residual contaminants. Furthermore, the addition of quicklime to soil during tailing can reduce the residual concentrations rapidly to below the remedial target values required for site remediation. Finally, mechanical soil aeration can be enhanced using quicklime, which can improve the volatilization of VCHs via increasing soil temperature, reducing soil moisture, and enhancing soil permeability. Our findings give a basic understanding to the elimination of the tailing in the application of mechanical soil aeration, particularly for VOCs-contaminated soils. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Pilot-scale bioremediation of a petroleum hydrocarbon-contaminated clayey soil from a sub-Arctic site

    International Nuclear Information System (INIS)

    Akbari, Ali; Ghoshal, Subhasis

    2014-01-01

    Highlights: • Aeration and moisture addition alone caused extensive hydrocarbon biodegradation. • 30-day slurry reactor remediation endpoints attained in 385 days in biopiles. • High nitrogen concentrations inhibited hydrocarbon degradation. • Inhibition of biodegradation linked to lack of shifts in soil microbial community. - Abstract: Bioremediation is a potentially cost-effective solution for petroleum contamination in cold region sites. This study investigates the extent of biodegradation of petroleum hydrocarbons (C16–C34) in a pilot-scale biopile experiment conducted at 15 °C for periods up to 385 days, with a clayey soil, from a crude oil-impacted site in northern Canada. Although several studies on bioremediation of petroleum hydrocarbon-contaminated soils from cold region sites have been reported for coarse-textured, sandy soils, there are limited studies of bioremediation of petroleum contamination in fine-textured, clayey soils. Our results indicate that aeration and moisture addition was sufficient for achieving 47% biodegradation and an endpoint of 530 mg/kg for non-volatile (C16–C34) petroleum hydrocarbons. Nutrient amendment with 95 mg-N/kg showed no significant effect on biodegradation compared to a control system without nutrient but similar moisture content. In contrast, in a biopile amended with 1340 mg-N/kg, no statistically significant biodegradation of non-volatile fraction was detected. Terminal Restriction Fragment Length Polymorphism (T-RFLP) analyses of alkB and 16S rRNA genes revealed that inhibition of hydrocarbon biodegradation was associated with a lack of change in microbial community composition. Overall, our data suggests that biopiles are feasible for attaining the bioremediation endpoint in clayey soils. Despite the significantly lower biodegradation rate of 0.009 day −1 in biopile tank compared to 0.11 day −1 in slurry bioreactors for C16–C34 hydrocarbons, the biodegradation extents for this fraction were

  7. Chemical Composition of Volatiles; Antimicrobial, Antioxidant and Cholinesterase Inhibitory Activity of Chaerophyllum aromaticum L. (Apiaceae) Essential Oils and Extracts.

    Science.gov (United States)

    Petrović, Goran M; Stamenković, Jelena G; Kostevski, Ivana R; Stojanović, Gordana S; Mitić, Violeta D; Zlatković, Bojan K

    2017-05-01

    The present study reports the chemical composition of the headspace volatiles (HS) and essential oils obtained from fresh Chaerophyllum aromaticum root and aerial parts in full vegetative phase, as well as biological activities of their essential oils and MeOH extracts. In HS samples, the most dominant components were monoterpene hydrocarbons. On the other hand, the essential oils consisted mainly of sesquiterpenoids, representing 73.4% of the root and 63.4% of the aerial parts essential oil. The results of antibacterial assay showed that the aerial parts essential oil and MeOH extract have no antibacterial activity, while the root essential oil and extract showed some activity. Both of the tested essential oils exhibited anticholinesterase activity (47.65% and 50.88%, respectively); MeOH extract of the root showed only 8.40% inhibition, while aerial part extract acted as an activator of cholinesterase. Regarding the antioxidant activity, extracts were found to be more effective than the essential oils. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  8. Difference in volatile composition between the pericarp tissue and inner tissue of tomato (Solanum lycopersicum) fruit

    Science.gov (United States)

    Numerous studies have reported the volatile profiles in the whole fruit or pericarp tissue of tomato (Solanum lycopersicum) fruit; however, information is limited on the volatile composition in the inner tissue and its contribution to tomato aroma. For this, the pericarps and inner tissues of “Money...

  9. Nonvolatile, semivolatile, or volatile: redefining volatile for volatile organic compounds.

    Science.gov (United States)

    Võ, Uyên-Uyén T; Morris, Michael P

    2014-06-01

    Although widely used in air quality regulatory frameworks, the term "volatile organic compound" (VOC) is poorly defined. Numerous standardized tests are currently used in regulations to determine VOC content (and thus volatility), but in many cases the tests do not agree with each other, nor do they always accurately represent actual evaporation rates under ambient conditions. The parameters (time, temperature, reference material, column polarity, etc.) used in the definitions and the associated test methods were created without a significant evaluation of volatilization characteristics in real world settings. Not only do these differences lead to varying VOC content results, but occasionally they conflict with one another. An ambient evaporation study of selected compounds and a few formulated products was conducted and the results were compared to several current VOC test methodologies: SCAQMD Method 313 (M313), ASTM Standard Test Method E 1868-10 (E1868), and US. EPA Reference Method 24 (M24). The ambient evaporation study showed a definite distinction between nonvolatile, semivolatile, and volatile compounds. Some low vapor pressure (LVP) solvents, currently considered exempt as VOCs by some methods, volatilize at ambient conditions nearly as rapidly as the traditional high-volatility solvents they are meant to replace. Conversely, bio-based and heavy hydrocarbons did not readily volatilize, though they often are calculated as VOCs in some traditional test methods. The study suggests that regulatory standards should be reevaluated to more accurately reflect real-world emission from the use of VOC containing products. The definition of VOC in current test methods may lead to regulations that exclude otherwise viable alternatives or allow substitutions of chemicals that may limit the environmental benefits sought in the regulation. A study was conducted to examine volatility of several compounds and a few formulated products under several current VOC test

  10. Characterisation of commercial aromatised vinegars: phenolic compounds, volatile composition and antioxidant activity.

    Science.gov (United States)

    Cejudo-Bastante, María J; Durán-Guerrero, Enrique; Natera-Marín, Ramón; Castro-Mejías, Remedios; García-Barroso, Carmelo

    2013-04-01

    Nineteen commercially available aromatised vinegars, which were representative of this type of product, were tested to ascertain their phenolic and volatile composition and antioxidant activity. The aromatised vinegars came from different raw materials such as fruits, spices, herbs and vegetables. The antioxidant activity was determined by means of photochemiluminescence, phenolic profile by using ultra performance liquid chromatography with ultraviolet detection, and the volatile composition was determined by using stir bar sorptive extraction-gas chromatography-mass spectrometry. Nine polyphenolic compounds and 141 volatile compounds were identified. Vinegar aromatised with black truffle and rosemary obtained the highest values of antioxidant activity, followed by those aromatised with lemon, tarragon, aromatic herbs and vegetables. Antioxidant activity was highly correlated with the presence of trans-p-coutaric acid, trans-caftaric acid, 5-hydroxy-methylfurfural and furfural. Moreover, (Z)-3-hexen-1-ol was exclusive to the vinegar aromatised with tarragon, while p-menth-1,8-ol, dimethyl styrene, 4-methyl acetophenone and nootkatone were only found in vinegar aromatised with lemon. On the basis of the results from the cluster analysis of cases, it can be concluded that the grouping responds more to the trademark of each vinegar than to the raw material. © 2012 Society of Chemical Industry.

  11. The volatile oil composition of fresh and air-dried buds of Cannabis sativa.

    Science.gov (United States)

    Ross, S A; ElSohly, M A

    1996-01-01

    The composition of the steam-distilled volatile oil of fresh and air-dried, indoor-grown marijuana was studied by GC/FID and GC/MS. In all, 68 components were detected of which 57 were fully identified. Drying of the plant material had no effect on the qualitative composition of the oil and did not affect the ability of individuals familiar with marijuana smell to recognize the odor.

  12. Comparative study of the volatile oil content and antimicrobial activity of Psidium guajava L. and Psidium cattleianum Sabine leaves

    Directory of Open Access Journals (Sweden)

    Fathy M. Soliman

    2016-12-01

    Full Text Available The chemical composition of the hydrodistilled oils of the leaves of Psidium guajava L. (guava leaf and Psidium cattleianum Sabine (strawberry guava was determined by GC/MS analysis to identify their chemotypes. Moreover, in vitro antimicrobial activity of these volatile oils against selected bacteria, yeast, and mycelia fungi was studied. The yield of the volatile oil hydrodistilled from the leaves of P. guajava L. and P. cattleianum Sabine was 1.6 and 2.69 g/kg on fresh weight basis, respectively. Limonene was the major identified hydrocarbon in P. guava leaves’ oil (54.70%, whereas, 1, 8-cineole was the major identified oxygenated monoterpenoid (32.14% in common guava leaves. The foliar oil of P. cattleianum was predominated by the sesquiterpene hydrocarbon; β-caryophyllene representing 28.83% of the total oil make-up. The antibacterial activity of guava leaf oil was more pronounced against Bacillus subtilis, Staphylococcus aureus, Streptococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa than that of strawberry guava leaves, while P. cattleianum showed a higher activity against ess. The MIC of the volatile oil of the leaves of P. guajava against S. aureus was 6.75 μg/ml, while that of P. cattleianum exhibited MIC value of 13.01 μg/ml against Neisseria gonorrhoeae. Results demonstrated that the volatile oil of both Psidium species showed different chemotypes. Moreover, the volatile oils of guava and strawberry guava leaves might be good candidates as antimicrobial agents.

  13. Pilot-scale bioremediation of a petroleum hydrocarbon-contaminated clayey soil from a sub-Arctic site.

    Science.gov (United States)

    Akbari, Ali; Ghoshal, Subhasis

    2014-09-15

    Bioremediation is a potentially cost-effective solution for petroleum contamination in cold region sites. This study investigates the extent of biodegradation of petroleum hydrocarbons (C16-C34) in a pilot-scale biopile experiment conducted at 15°C for periods up to 385 days, with a clayey soil, from a crude oil-impacted site in northern Canada. Although several studies on bioremediation of petroleum hydrocarbon-contaminated soils from cold region sites have been reported for coarse-textured, sandy soils, there are limited studies of bioremediation of petroleum contamination in fine-textured, clayey soils. Our results indicate that aeration and moisture addition was sufficient for achieving 47% biodegradation and an endpoint of 530 mg/kg for non-volatile (C16-C34) petroleum hydrocarbons. Nutrient amendment with 95 mg-N/kg showed no significant effect on biodegradation compared to a control system without nutrient but similar moisture content. In contrast, in a biopile amended with 1340 mg-N/kg, no statistically significant biodegradation of non-volatile fraction was detected. Terminal Restriction Fragment Length Polymorphism (T-RFLP) analyses of alkB and 16S rRNA genes revealed that inhibition of hydrocarbon biodegradation was associated with a lack of change in microbial community composition. Overall, our data suggests that biopiles are feasible for attaining the bioremediation endpoint in clayey soils. Despite the significantly lower biodegradation rate of 0.009 day(-1) in biopile tank compared to 0.11 day(-1) in slurry bioreactors for C16-C34 hydrocarbons, the biodegradation extents for this fraction were comparable in these two systems. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Rapid computation of chemical equilibrium composition - An application to hydrocarbon combustion

    Science.gov (United States)

    Erickson, W. D.; Prabhu, R. K.

    1986-01-01

    A scheme for rapidly computing the chemical equilibrium composition of hydrocarbon combustion products is derived. A set of ten governing equations is reduced to a single equation that is solved by the Newton iteration method. Computation speeds are approximately 80 times faster than the often used free-energy minimization method. The general approach also has application to many other chemical systems.

  15. Amino Acid Profile and Volatile Flavour Compounds of Raw and Steamed Patin Catfish (Pangasius hypophthalmus) and Narrow-barred Spanish Mackerel (Scomberomorus commerson)

    Science.gov (United States)

    Pratama, Rusky I.; Rostini, I.; Rochima, E.

    2018-02-01

    Fish species and processing methods could affect the volatile flavour composition and amino acid profile of fishery commodity. The objectives of this study were to identify volatile components and amino acid profile of two considered predominant fish species in Indonesia which are freshwater Patin catfish (Pangasius hypophthalmus) and marine water fish, Spanish mackerel (Scomberomorus commerson). The methods used in this study were to detect volatile compounds using Gas Chromatography/Mass Spectrometry (GC/MS) on fresh and steamed of both species samples (100°C for 30 minutes) and amino acid profile were also analyzed using High Performance Liquid Chromatography (HPLC). The volatile components analysis successfully detects as much as 29 and 59 volatiles compounds in fresh and steamed Patin catfish respectively, while 37 and 102 compounds were detected in fresh and steamed Spanish mackerel samples. Most of detected components derives from hydrocarbons, aldehydes, alcohols and ketone groups which could affected by their chemical composition and resulted from various thermal involved reaction. The amino acids profile identification results showed that glutamic acid was found higher compared to other amino acids standards in both samples. Glutamic acid is non-essential amino acid which is important in umami taste substances.

  16. Characterization of selected volatile organic compounds, polycyclic aromatic hydrocarbons and carbonyl compounds at a roadside monitoring station

    Science.gov (United States)

    Ho, K. F.; Lee, S. C.; Chiu, Gloria M. Y.

    Volatile organic compounds (VOCs), PAHs and carbonyl compounds are the major toxic components in Hong Kong. Emissions from motor vehicles have been one of the primary pollution sources in the metropolitan areas throughout Hong Kong for a long time. A 1-yr monitoring program for VOCs, PAHs and carbonyl compounds had been performed at a roadside urban station at Hong Kong Polytechnic University in order to determine the variations and correlations of each selected species (VOCs, PAHs and carbonyl compounds). This study is aimed to analyze toxic volatile organic compounds (benzene, toluene, ethylbenzene and xylene), two carbonyl compounds (formaldehyde, acetaldehyde), and selective polycyclic aromatic hydrocarbons. The monitoring program started from 16 April 1999 to 30 March 2000. Ambient VOC concentrations, many of which originate from the same sources as particulate PAHs and carbonyls compounds, show significant quantities of benzene, toluene and xylenes. Correlations and multivariate analysis of selected gaseous and particulate phase organic pollutants were performed. Source identification by principle component analysis and hierarchical cluster analysis allowed the identification of four sources (factors) for the roadside monitoring station. Factor 1 represents the effect of diesel vehicle exhaust. Factor 2 shows the contribution of aromatic compounds. Factor 3 explains photochemical products—formaldehyde and acetaldehyde. Factor 4 explains the effect of gasoline vehicle exhaust.

  17. Distribution of volatile composition in 'marion' ( rubus species hyb) blackberry pedigree.

    Science.gov (United States)

    Du, Xiaofen; Finn, Chad; Qian, Michael C

    2010-02-10

    The distribution of volatile constituents in ancestral genotypes of 'Marion' blackberry's pedigree was investigated over two growing seasons. Each genotype in the pedigree had a specific volatile composition. Red raspberry was dominated by norisoprenoids, lactones, and acids. 'Logan' and 'Olallie' also had a norisoprenoid dominance but at much lower concentrations. The concentration of norisoprenoids in other blackberry genotypes was significantly lower. Terpenes and furanones were predominant in wild 'Himalaya' blackberry, whereas terpenes were the major volatiles in 'Santiam'. 'Marion', a selection from 'Chehalem' and 'Olallie', contained almost all of the volatile compounds in its pedigree at moderate amount. The chiral isomeric ratios of 11 pairs of compounds were also studied. Strong chiral isomeric preference was observed for most of the chiral compounds, and each cultivar had its unique chiral isomeric distribution. An inherent pattern was observed for some volatile compounds in the 'Marion' pedigree. Raspberry and 'Logan' had a very high concentration of beta-ionone, but was reduced by half in 'Olallie' and by another half in 'Marion' as the crossing proceeded. A high content of linalool in 'Olallie' and a low content in 'Chehalem' resulted in a moderate content of linalool in their progeny 'Marion'. However, the concentration of furaneol in 'Marion' was higher than in its parents. A high content of (S)-linalool in 'Olallie' and a racemic content of (S)-,(R)-linalool in 'Chehalem' resulted in a preference for the (S)-form in 'Marion'.

  18. Volatile Short-chain Chlorinated Hydrocarbons in the Groundwater of the City of Zagreb

    Directory of Open Access Journals (Sweden)

    Marijanović-Rajčić, M.

    2008-01-01

    Full Text Available The aim of the study was to assess the quality of the groundwater sampled from private wells and the public water-supply system in terms of estimating the contamination caused by short-chain chlorinated hydrocarbons, as well as to estimate the exposure of the citizens dwelling in different suburbs to these pollutants of their drinking water (Fig. 1. The aim of the study was also to determine which suburb is supplied through the public water-supply system with water originating from the Sašnak spring that is contaminated with volatile chlorinated short-chain hydrocarbons.Drinking water samples were taken from 3 private wells and 1 public water-supply system situated in 3 Zagreb suburbs - Pešćenica, Trnje, and Trešnjevka. The sampling was carried out during 2003 and was undertaken on a seasonal basis. Short-chain chlorinated hydrocarbons - 1,1,1-trichloroethane, carbon tetrachloride, 1,1,2-trichloroethene and 1,1,2,2-tetrachloroethene - were determined by gas chromatography, following "liquid-liquid extraction" in pentane. For that purpose, we applied the gas chromatograph equipped with an electron-capture detector, thermo-programmable operations, and a suitable capillary column. The technique applied was that of split-injection.The groundwater of the City of Zagreb was found to be contaminated with volatile chlorinated hydrocarbons. The concentration level of 1,1,1-trichloroethane, determined in most of the samples, was found to be low (Fig. 2. On the other hand, 1,1,2-trichloroethene was present in all samples in concentrations of about 1 µg l-1- (Fig. 3. Only the drinking water samples taken from private wells in the suburb of Trnje contained somewhat higher mass concentrations of 1,1,1-trichloroethane, with the peak value of 19.03 µg l-1, measured in the winter season. In the samples taken from private wells in Trnje, the mass concentrations of 1,1,2,2-tetrachloroethene rangedfrom 15.30 µg l-1 to 18.65 µg l-1, as measured in autumn

  19. Effect of post-fermentation and packing stages on the volatile composition of Spanish-style green table olives.

    Science.gov (United States)

    Sánchez, Antonio Higinio; López-López, Antonio; Cortés-Delgado, Amparo; Beato, Víctor Manuel; Medina, Eduardo; de Castro, Antonio; Montaño, Alfredo

    2018-01-15

    The volatile profile of Spanish-style green table olives after fermentation and the changes in volatile compounds that occurred as a result of the post-fermentation and subsequent packing stage were explored by solid phase micro-extraction (SPME) and gas chromatography coupled to mass spectrometry (GC-MS). Three olive cultivars (Manzanilla, Gordal, and Hojiblanca) were processed and olive samples were taken at three different times throughout the elaboration: after fermentation, after post-fermentation, and after packing. A total of 132 volatile compounds were identified, including 10 phenols, 25 alcohols, 11 acids, 39 esters, 8 hydrocarbons, 14 carbonyl compounds, 17 terpenes, and 6 other compounds. A varying number of compounds from each chemical family underwent significant changes because of the post-fermentation and packing stages. Among them, some typical reaction products of lipid oxidation (e.g. (E)-2-decenal and (E,E)-2,4-decadienal) increased with the post-fermentation in Manzanilla cultivar, and also as a result of packing in all three cultivars. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Volatile Composition and Enantioselective Analysis of Chiral Terpenoids of Nine Fruit and Vegetable Fibres Resulting from Juice Industry By-Products

    Directory of Open Access Journals (Sweden)

    Alexis Marsol-Vall

    2017-01-01

    Full Text Available Fruit and vegetable fibres resulting as by-products of the fruit juice industry have won popularity because they can be valorised as food ingredients. In this regard, bioactive compounds have already been studied but little attention has been paid to their remaining volatiles. Considering all the samples, 57 volatiles were identified. Composition greatly differed between citrus and noncitrus fibres. The former presented over 90% of terpenoids, with limonene being the most abundant and ranging from 52.7% in lemon to 94.0% in tangerine flesh. Noncitrus fibres showed more variable compositions, with the predominant classes being aldehydes in apple (57.5% and peach (69.7%, esters (54.0% in pear, and terpenoids (35.3% in carrot fibres. In addition, enantioselective analysis of some of the chiral terpenoids present in the fibre revealed that the enantiomeric ratio for selected compounds was similar to the corresponding volatile composition of raw fruits and vegetables and some derivatives, with the exception of terpinen-4-ol and α-terpineol, which showed variation, probably due to the drying process. The processing to which fruit residues were submitted produced fibres with low volatile content for noncitrus products. Otherwise, citrus fibres analysed still presented a high volatile composition when compared with noncitrus ones.

  1. Distribution and Fractional Composition of Petroleum Hydrocarbons in Roadside Soils

    Directory of Open Access Journals (Sweden)

    Larysa Mykhailova

    2013-01-01

    Full Text Available Total petroleum hydrocarbon (TPH concentrations and their fractional composition (medium fraction: n-alkane chain-length C15 to C27, heavy fraction: >C27 were determined at distances from 1 to 60 m from roads and at soil depths from 0.5 to 15 cm. The traffic intensities were up to 25000 vehicles per day. Soil TPH concentrations were highest within 15 m distance (665 and 3198 mg kg−1 at the windward and leeward sides, resp., followed by a rapid drop to background values beyond (196 and 115 mg kg−1 in 60 m distance at the windward and leeward sides, resp.. The data variability was lowest at distances of 1 m and highest within tree plantations at distances of 15 m from the road. The TPH concentrations decreased with depth but were significantly higher than the background at all depths investigated. A principal component analysis revealed a positive relation between the medium-to-heavy fraction ratio and soil depth. A fractional differentiation of hydrocarbons with distance from road was not observed. It was concluded that the assessment of the potential of hydrocarbons to translocate, accumulate, or degrade in soil necessitates their subdivision into fractions based on their physicochemical and metabolic properties.

  2. Microbial Hydrocarbon and ToxicPollutant Degradation Method

    Energy Technology Data Exchange (ETDEWEB)

    Schlueter, Dietrich [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Janabi, Mustafa [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); O' Neil, James [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Budinger, Thomas [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2011-08-16

    The goal of this project is to determine optimum conditions for bacterial oxidation of hydrocarbons and long-chain alkanes that are representative of petroleum contamination of the environment. Polycyclic Aromatic Hydrocarbons (PAHs) are of concern because of their toxicity, low volatility, and resistance to microbial degradation, especially under anaerobic conditions. The uniqueness of our approach is to use carbon-11 in lieu of the traditional use of carbon-14.

  3. Chemical Composition and Biological Activity of Volatile Extracts from Leaves and Fruits of Schinusterebinthifolius Raddi from Tunisia

    Directory of Open Access Journals (Sweden)

    Alessandra Piras

    2017-01-01

    Full Text Available Volatile oils composition from leaves and ripe fruits of pink pepper (Schinus terebinthifolius Raddi growing in Tunisia were investigated using GC-FID and GC-MS techniques. Volatile oil extraction was achieved by hydrodistillation (HD using a Clevenger apparatus and by supercritical fluid extraction (SFE using carbon dioxide. All plant organs, gave SFE extracts chiefly composed by a -pinene, a -phellandrene, b -phellandrene, germacrene D and bicyclogermacrene. In the case of the fruits, both extraction techniques gave volatile oils of similar composition; whereas the comparison between the HD and SFE leave oils revealed important differences in the content of a -pinene (6.1 % vs traces, a -phellandrene (22.7 % vs 0.8 % and b -phellandrene (14.6 % vs 1.2 %. All volatile samples were evaluated against yeasts and dermatophyte strains, being more active against Cryptococcus neoformans, particularly the volatile oil from the fruits, with MIC values of (0.32-0.64 mg/mL.Moreover, this oil revealed an inhibitory effect on germ tube formation in C. albicans at sub-inhibitory concentration. At the concentration of MIC/8 the inhibition of filamentation was more than 70 %.

  4. The effects of diet and breed on the volatile compounds of cooked lamb.

    Science.gov (United States)

    Elmore, J S; Mottram, D S; Enser, M; Wood, J D

    2000-06-01

    The effect of varying the n-3 polyunsaturated fatty acid (PUFA) composition of lamb muscle on the formation of aroma volatiles during cooking has been examined. The meat was obtained from four groups of Suffolk and Soay lambs fed different supplementary fats: a palm-oil based control; bruised whole linseed, which increased muscle levels of α-linolenic acid (C18:3 n-3); fish oil, which increased eicosapentaenoic acid (EPA, C20:5 n-3) and docosahexaenoic acid (DHA, C22:6 n-3); and equal quantities of linseed and fish oil (fat basis). Higher quantities of lipid oxidation products were found in the aroma volatiles of lamb muscle from animals fed fish oil, compared to the control. In particular, unsaturated aldehydes, unsaturated hydrocarbons and alkylfurans increased up to fourfold. These compounds derived from the autoxidation of PUFAs during cooking. Although some of these volatiles were increased in meat from animals fed the linseed supplement, the effect was not as great as with the fish oil fed lambs. Levels of volatiles derived from the Maillard reaction, such as pyrazines and sulfur compounds, were up to four times higher in Soays than Suffolks.

  5. Pilot-scale bioremediation of a petroleum hydrocarbon-contaminated clayey soil from a sub-Arctic site

    Energy Technology Data Exchange (ETDEWEB)

    Akbari, Ali; Ghoshal, Subhasis, E-mail: subhasis.ghoshal@mcgill.ca

    2014-09-15

    Highlights: • Aeration and moisture addition alone caused extensive hydrocarbon biodegradation. • 30-day slurry reactor remediation endpoints attained in 385 days in biopiles. • High nitrogen concentrations inhibited hydrocarbon degradation. • Inhibition of biodegradation linked to lack of shifts in soil microbial community. - Abstract: Bioremediation is a potentially cost-effective solution for petroleum contamination in cold region sites. This study investigates the extent of biodegradation of petroleum hydrocarbons (C16–C34) in a pilot-scale biopile experiment conducted at 15 °C for periods up to 385 days, with a clayey soil, from a crude oil-impacted site in northern Canada. Although several studies on bioremediation of petroleum hydrocarbon-contaminated soils from cold region sites have been reported for coarse-textured, sandy soils, there are limited studies of bioremediation of petroleum contamination in fine-textured, clayey soils. Our results indicate that aeration and moisture addition was sufficient for achieving 47% biodegradation and an endpoint of 530 mg/kg for non-volatile (C16–C34) petroleum hydrocarbons. Nutrient amendment with 95 mg-N/kg showed no significant effect on biodegradation compared to a control system without nutrient but similar moisture content. In contrast, in a biopile amended with 1340 mg-N/kg, no statistically significant biodegradation of non-volatile fraction was detected. Terminal Restriction Fragment Length Polymorphism (T-RFLP) analyses of alkB and 16S rRNA genes revealed that inhibition of hydrocarbon biodegradation was associated with a lack of change in microbial community composition. Overall, our data suggests that biopiles are feasible for attaining the bioremediation endpoint in clayey soils. Despite the significantly lower biodegradation rate of 0.009 day{sup −1} in biopile tank compared to 0.11 day{sup −1} in slurry bioreactors for C16–C34 hydrocarbons, the biodegradation extents for this fraction

  6. Sensory characteristics and volatile composition of a cereal beverage fermented with Bifidobacterium breve NCIMB 702257.

    Science.gov (United States)

    Salmerón, Ivan; Rozada, Raquel; Thomas, Keith; Ortega-Rivas, Enrique; Pandiella, Severino S

    2014-04-01

    Most of the commercialized lactic acid fermented products are dairy-based. Hence, the development of non-dairy fermented products with probiotic properties draws significant attention within the functional foods industry. The microorganisms used in such products have complex enzyme systems through which they generate diverse metabolites (volatile and non-volatile) that provide significant flavour attributes of importance for fermented foods. The correlation of the volatile flavour compounds of a malt beverage fermented with a Bifidobacterium breve strain with its unique sensory characteristics was performed. The volatile composition analysis exposed the presence of 12 components. Eight of these flavour volatiles were produced through the metabolic activity of the bifidobacteria strain. Notably acetic acid, of reported sour flavour characteristics, exhibited the greatest intensity. Four components of considerable organoleptic characteristics were identified as Maillard-derived products, namely maltol, pyranone, 2 (5H)-furanmethanol and 3-furanmethanol. The sensory evaluation exhibited that the fermented cereal beverage had a sour flavour with mild sweet and malty notes. These results indicate that the volatile compounds identified can be appointed as significant flavour markers of the novel fermented cereal beverage.

  7. Thermal soil desorption for total petroleum hydrocarbon testing on gas chromatographs

    International Nuclear Information System (INIS)

    Mott, J.

    1995-01-01

    Testing for total petroleum hydrocarbons (TPH) is one of the most common analytical tests today. A recent development in chromatography incorporates Thermal Soil Desorption technology to enable analyses of unprepared soil samples for volatiles such as BTEX components and semi-volatiles such as diesel, PCBs, PAHs and pesticides in the same chromatogram, while in the field. A gas chromatograph is the preferred method for determining TPH because the column in a GC separates the individual hydrocarbons compounds such as benzene and toluene from each other and measures each individually. A GC analysis will determine not only the total amount of hydrocarbon, but also whether it is gasoline, diesel or another compound. TPH analysis with a GC is typically conducted with a Flame Ionization Detector (FID). Extensive field and laboratory testing has shown that incorporation of a Thermal Soil Desorber offers many benefits over traditional analytical testing methods such as Headspace, Solvent Extraction, and Purge and Trap. This paper presents the process of implementing Thermal Soil Desorption in gas chromatography, including procedures for, and advantages of faster testing and analysis times, concurrent volatile and semi-volatile analysis, minimized sample manipulation, single gas (H 2 ) operation, and detection to the part-per billion levels

  8. Quantification of compositional changes of petroleum hydrocarbons by GC/FID and GC/MS during a long-term bioremediation experiment

    DEFF Research Database (Denmark)

    Jensen, Trine S.; Arvin, Erik; Svensmark, Bo

    2000-01-01

    Samples from a long-term bioremediation experiment contaminated with two crude oils, Arabian Heavy and Gullfax, was used to analyze the compositional change of petroleum hydrocarbons. A time course of five different homologous series of petroleum hydrocarbons were analysed by GC/FID and GC...

  9. Influence of yeast strain, canopy management, and site on the volatile composition and sensory attributes of cabernet sauvignon wines from Western Australia.

    Science.gov (United States)

    Robinson, Anthony L; Boss, Paul K; Heymann, Hildegarde; Solomon, Peter S; Trengove, Robert D

    2011-04-13

    Understanding what factors are the major influences on wine composition will assist in the successful management of grape composition in the vineyard and/or variables in the winery to produce wines with specific sensory attributes. A recently developed analytical method [headspace solid-phase microextraction comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry] was employed to analyze over 350 volatile compounds in research scale wines and was combined with descriptive sensory analysis. Both compositional and sensory results showed significant differences among the wines, and in many cases, multiple factors influenced the abundance of wine volatile compounds. Site had the most significant influence on sensory scores and wine composition, followed by canopy management. Unexpectedly, yeast strain had no significant sensory effect despite the fact that a number of volatile compounds were significantly different in the wines made from different strains. PLS analysis, combining the sensory and chemical analyses, also supports the concept of volatile compound interactions contributing to the aroma characteristics of Cabernet Sauvignon wine.

  10. Change in Color and Volatile Composition of Skim Milk Processed with Pulsed Electric Field and Microfiltration Treatments or Heat Pasteurization.

    Science.gov (United States)

    Chugh, Anupam; Khanal, Dipendra; Walkling-Ribeiro, Markus; Corredig, Milena; Duizer, Lisa; Griffiths, Mansel W

    2014-04-23

    Non-thermal processing methods, such as pulsed electric field (PEF) and tangential-flow microfiltration (TFMF), are emerging processing technologies that can minimize the deleterious effects of high temperature short time (HTST) pasteurization on quality attributes of skim milk. The present study investigates the impact of PEF and TFMF, alone or in combination, on color and volatile compounds in skim milk. PEF was applied at 28 or 40 kV/cm for 1122 to 2805 µs, while microfiltration (MF) was conducted using membranes with three pore sizes (lab-scale 0.65 and 1.2 µm TFMF, and pilot-scale 1.4 µm MF). HTST control treatments were applied at 75 or 95 °C for 20 and 45 s, respectively. Noticeable color changes were observed with the 0.65 µm TFMF treatment. No significant color changes were observed in PEF-treated, 1.2 µm TFMF-treated, HTST-treated, and 1.4 µm MF-treated skim milk ( p ≥ 0.05) but the total color difference indicated better color retention with non-thermal preservation. The latter did not affect raw skim milk volatiles significantly after single or combined processing ( p ≥ 0.05), but HTST caused considerable changes in their composition, including ketones, free fatty acids, hydrocarbons, and sulfur compounds ( p < 0.05). The findings indicate that for the particular thermal and non-thermal treatments selected for this study, better retention of skim milk color and flavor components were obtained for the non-thermal treatments.

  11. Change in Color and Volatile Composition of Skim Milk Processed with Pulsed Electric Field and Microfiltration Treatments or Heat Pasteurization

    Directory of Open Access Journals (Sweden)

    Anupam Chugh

    2014-04-01

    Full Text Available Non-thermal processing methods, such as pulsed electric field (PEF and tangential-flow microfiltration (TFMF, are emerging processing technologies that can minimize the deleterious effects of high temperature short time (HTST pasteurization on quality attributes of skim milk. The present study investigates the impact of PEF and TFMF, alone or in combination, on color and volatile compounds in skim milk. PEF was applied at 28 or 40 kV/cm for 1122 to 2805 µs, while microfiltration (MF was conducted using membranes with three pore sizes (lab-scale 0.65 and 1.2 µm TFMF, and pilot-scale 1.4 µm MF. HTST control treatments were applied at 75 or 95 °C for 20 and 45 s, respectively. Noticeable color changes were observed with the 0.65 µm TFMF treatment. No significant color changes were observed in PEF-treated, 1.2 µm TFMF-treated, HTST-treated, and 1.4 µm MF-treated skim milk (p ≥ 0.05 but the total color difference indicated better color retention with non-thermal preservation. The latter did not affect raw skim milk volatiles significantly after single or combined processing (p ≥ 0.05, but HTST caused considerable changes in their composition, including ketones, free fatty acids, hydrocarbons, and sulfur compounds (p < 0.05. The findings indicate that for the particular thermal and non-thermal treatments selected for this study, better retention of skim milk color and flavor components were obtained for the non-thermal treatments.

  12. Relationship between sensory attributes and volatile compounds of polish dry-cured loin

    Science.gov (United States)

    Górska, Ewa; Nowicka, Katarzyna; Jaworska, Danuta; Przybylski, Wiesław; Tambor, Krzysztof

    2017-01-01

    Objective The aim of this work was to determine the relationship between objective sensory descriptors and volatile flavour compound composition of Polish traditional dry-cured loin. Methods The volatile compounds were investigated by using solid phase microextraction (SPME) and gas chromatography–mass spectrometry (GC–MS). For sensory assessment, the quantitative descriptive analysis (QDA) method was used. Results A total of 50 volatile compounds were found and assigned to 17 chemical families. Most of the detected volatile compounds derived from smoking, lipid oxidative reactions and seasoning (46.8%, 21.7%, and 18.9%, respectively). The dominant compounds were: aromatic hydrocarbon (toluene); alkanes (hexane, heptane, and 2,2,4-trimethylpentane); aldehyde (hexanal); alcohol (2-furanmethanol); ketone (3-hydroxy-2-butanone); phenol (guaiacol); and terpenes (eucalyptol, cymene, γ-terpinen, and limonene). Correlation analysis showed that some compounds derived from smoking were positively correlated with the intensity of cured meat odour and flavour and negatively with the intensity of dried meat odour and flavour, while terpenes were strongly correlated with odour and flavour of added spices. Conclusion The analysed dry-cured loins were characterized by specific and unique sensory profile. Odour and flavour of studied loins was mainly determined by volatile compounds originating from smoking, seasoning and lipid oxidation. Obtained results suggest that smoking process is a crucial stage during Polish traditional dry-cured loins production. PMID:27456422

  13. Relationship between sensory attributes and volatile compounds of polish dry-cured loin

    Directory of Open Access Journals (Sweden)

    Ewa Górska

    2017-05-01

    Full Text Available Objective The aim of this work was to determine the relationship between objective sensory descriptors and volatile flavour compound composition of Polish traditional dry-cured loin. Methods The volatile compounds were investigated by using solid phase microextraction (SPME and gas chromatography–mass spectrometry (GC–MS. For sensory assessment, the quantitative descriptive analysis (QDA method was used. Results A total of 50 volatile compounds were found and assigned to 17 chemical families. Most of the detected volatile compounds derived from smoking, lipid oxidative reactions and seasoning (46.8%, 21.7%, and 18.9%, respectively. The dominant compounds were: aromatic hydrocarbon (toluene; alkanes (hexane, heptane, and 2,2,4-trimethylpentane; aldehyde (hexanal; alcohol (2-furanmethanol; ketone (3-hydroxy-2-butanone; phenol (guaiacol; and terpenes (eucalyptol, cymene, γ-terpinen, and limonene. Correlation analysis showed that some compounds derived from smoking were positively correlated with the intensity of cured meat odour and flavour and negatively with the intensity of dried meat odour and flavour, while terpenes were strongly correlated with odour and flavour of added spices. Conclusion The analysed dry-cured loins were characterized by specific and unique sensory profile. Odour and flavour of studied loins was mainly determined by volatile compounds originating from smoking, seasoning and lipid oxidation. Obtained results suggest that smoking process is a crucial stage during Polish traditional dry-cured loins production.

  14. Physico-chemical, nutritional, and volatile composition and sensory profile of Spanish jujube (Ziziphus jujuba Mill.) fruits.

    Science.gov (United States)

    Hernández, Francisca; Noguera-Artiaga, Luis; Burló, Francisco; Wojdyło, Aneta; Carbonell-Barrachina, Ángel A; Legua, Pilar

    2016-06-01

    Jujube fruit is eaten mostly fresh, but may be dried (Chinese dates and tea) or processed into confectionary recipes in bread, cakes, compotes, and candy. Given that the quality of jujube available on the market differs on account of various factors such as geographical environment, cultivar, processing conditions, and storage conditions, and that, for consumers, flavour and nutrition properties of jujube represent the major parameters in determining the quality of jujube, the main goal of this study were to determine the main physico-chemical properties of jujube fruits, sugars and organic acids profiles, protein, mineral constituents, volatile composition and sensory profile of jujube fruits. This would allow breeders to select cultivars with higher levels of nutrients and also enable increasing dietary intake by consumers. Investigations showed that jujube fruit weight ranged from 4.8 to 29.3 g fruit(-1) . Four sugars (glucose, fructose, sucrose and sorbitol) and four organic acids (citric, malic, ascorbic and succinic acids) were identified and quantified by high-performance liquid chromatography in jujube fruits. Potassium, calcium and magnesium were the major mineral constituents in jujube fruits. Fifteen volatiles compounds were found in the aroma profile of jujube fruits (nine were aldehydes, three terpenes, one ester, one ketone and one linear hydrocarbon). The results showed that Spanish jujube cultivars studied are a good source of vitamin C, and they have a low content of Na. The jujube cultivar with the most appreciated quality by consumers was GAL; the GAL fruits were sweet, crunchy, and had high intensities of jujube ID and apple flavour a long after-taste. Therefore, jujube grown in Spain has a great potential to be exploited for functional foods. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  15. Chemical composition and seasonal variation of the volatile oils from Trembleya phlogiformis leaves

    Directory of Open Access Journals (Sweden)

    Sarah R. Fernandes

    Full Text Available ABSTRACT Trembleya phlogiformis DC., Melastomataceae, is a shrub whose leaves are used as a dye for dyeing wool and cotton. The present article aimed to carry out the morphological description of the species, to study the chemical composition of volatile oils from the leaves and flowers and the seasonal variability from the leaves during a year. Macroscopic characterization was carried out with the naked eye and with a stereoscopic microscope. Volatile oils were isolated by hydrodistillation in Clevenger apparatus and analyzed by gas chromatography/mass spectrometry. The major components of the volatile oil of T. phlogiformis flowers were: n-heneicosane (33.5%, phytol (12.3%, n-tricosane (8.4% and linoleic acid (6.1%. It was verified the existence of a large chemical variability of the volatile oils from the leaves of T. phlogiformis over the months, with the majority compound (oleic alcohol, ranging from 5.7 to 26.8% present in all samples. A combination of Cluster Analysis and Principal Component Analysis showed the existence of three main clusters, probably related to the seasons. The results suggested that the volatile oils of T. phlogiformis leaves possess high chemical variability, probably related to variation associated with rainfall and the variation in the behavior of specimens throughout the year. This research provides insights for future studies on the volatile oils obtained from the T. phlogiformis leaves and flowers, mainly related to biological markers of applications monitored in the leaves and flowers of this species.

  16. Volatile compounds in cryptic species of the Aneura pinguis complex and Aneura maxima (Marchantiophyta, Metzgeriidae).

    Science.gov (United States)

    Wawrzyniak, Rafał; Wasiak, Wiesław; Bączkiewicz, Alina; Buczkowska, Katarzyna

    2014-09-01

    Aneura pinguis is one of the liverwort species complexes that consist of several cryptic species. Ten samples collected from different regions in Poland are in the focus of our research. Eight of the A. pinguis complex belonging to four cryptic species (A, B, C, E) and two samples of closely related species Aneura maxima were tested for the composition of volatile compounds. The HS-SPME technique coupled to GC/FID and GC/MS analysis has been applied. The fiber coated with DVB/CAR/PDMS has been used. The results of the present study, revealed the qualitative and quantitative differences in the composition of the volatile compounds between the studied species. Mainly they are from the group of sesquiterpenoids, oxygenated sesquiterpenoids and aliphatic hydrocarbons. The statistical methods (CA and PCA) showed that detected volatile compounds allow to distinguish cryptic species of A. pinguis. All examined cryptic species of the A. pinguis complex differ from A. maxima. Species A and E of A. pinguis, in CA and PCA, form separate clusters remote from two remaining cryptic species of A. pinguis (B and C) and A. maxima. Relationship between the cryptic species appeared from the chemical studies are in accordance with that revealed on the basis of DNA sequences. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Measurement of stable carbon isotope ratios of non-methane hydrocarbons and halocarbons

    NARCIS (Netherlands)

    Zuiderweg, A.T.

    2012-01-01

    Within the realm of volatile organic compounds, hydrocarbons and halocarbons form a sizable proportion of carbon input to the atmosphere. Within these compound categories, the light non-methane hydrocarbons (NMHC, two to seven carbon atoms) and monocarbon halocarbons have a special place as these

  18. Volatile Organic Compounds in the Boundary Layer in Tikveš, Kopački Rit Nature Reserve

    Directory of Open Access Journals (Sweden)

    Kovač-Andrić, E.

    2013-07-01

    Full Text Available This paper represents one of the first measurements of volatile hydrocarbon concentrations within the surface layer of the troposphere in Tikveš, Kopaeki Rit Nature Park. This Nature Park is situated about 20 kilometres from the city of Osijek and represents an interesting example of the interaction of the urban and rural (wetland areas, which is also the reason for selecting the Tikveš site as the measurement station.Volatile organic compounds with two to seven carbon atoms were measured and analysed on a gas chromatograph with flame ionization (FID and mass-selective detector (MSD. The results for the hydrocarbons with 2 to 7 carbon atoms are shown. Ozone volume fractions in the air were also measured. All data obtained are given as hourly averages: for volatile hydrocarbons of concentrations and for ozone of volume fractions. The most significant changes in the concentration were found for ethane, propane and butane. With the exception of isoprene, whose daily concentration changes similarly as found for ozone, the daily variations of the measured hydrocarbons in Tikveš differ from the observed ozone diurnal variation. The Spearman's test showed no significant negative correlation between the measured hydrocarbons.

  19. Treatability of volatile chlorinated hydrocarbon-contaminated soils of different textures along a vertical profile by mechanical soil aeration: A laboratory test.

    Science.gov (United States)

    Ma, Yan; Shi, Yi; Hou, Deyi; Zhang, Xi; Chen, Jiaqi; Wang, Zhifen; Xu, Zhu; Li, Fasheng; Du, Xiaoming

    2017-04-01

    Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons (VCHs). Conventionally, this technique is used to treat the mixed soil of a site without considering the diversity and treatability of different soils within the site. A laboratory test was conducted to evaluate the effectiveness of mechanical soil aeration for remediating soils of different textures (silty, clayey, and sandy soils) along a vertical profile at an abandoned chloro-alkali chemical site in China. The collected soils were artificially contaminated with chloroform (TCM) and trichloroethylene (TCE). Mechanical soil aeration was effective for remediating VCHs (removal efficiency >98%). The volatilization process was described by an exponential kinetic function. In the early stage of treatment (0-7hr), rapid contaminant volatilization followed a pseudo-first order kinetic model. VCH concentrations decreased to low levels and showed a tailing phenomenon with very slow contaminant release after 8hr. Compared with silty and sandy soils, clayey soil has high organic-matter content, a large specific surface area, a high clay fraction, and a complex pore structure. These characteristics substantially influenced the removal process, making it less efficient, more time consuming, and consequently more expensive. Our findings provide a potential basis for optimizing soil remediation strategy in a cost-effective manner. Copyright © 2016. Published by Elsevier B.V.

  20. Selective adsorption of volatile hydrocarbons and gases in high surface area chalcogels containing [ES3]3- anions (E = As, Sb)

    KAUST Repository

    Ahmed, Ejaz; Khanderi, Jayaprakash; Anjum, Dalaver H.; Rothenberger, Alexander

    2014-01-01

    We describe the sol-gel synthesis of the two new chalcogels KFeSbS3 and NaFeAsS3, which demonstrate excellent adsorption selectivity for volatile hydrocarbons and gases. These predominantly mesoporous materials have been synthesized by reacting Fe(OAc)2 with K3SbS3 or Na3AsS3 in a formamide/water mixture at room temperature. Aerogels obtained after supercritical drying have BET surface areas of 636 m2/g and 505 m2/g for KFeSbS3 and NaFeAsS3, respectively, with pore sizes in the micro- (below 2 nm), meso- (2-50 nm), and macro- (above 50 nm) regions.

  1. Selective adsorption of volatile hydrocarbons and gases in high surface area chalcogels containing [ES3]3- anions (E = As, Sb)

    KAUST Repository

    Ahmed, Ejaz

    2014-11-25

    We describe the sol-gel synthesis of the two new chalcogels KFeSbS3 and NaFeAsS3, which demonstrate excellent adsorption selectivity for volatile hydrocarbons and gases. These predominantly mesoporous materials have been synthesized by reacting Fe(OAc)2 with K3SbS3 or Na3AsS3 in a formamide/water mixture at room temperature. Aerogels obtained after supercritical drying have BET surface areas of 636 m2/g and 505 m2/g for KFeSbS3 and NaFeAsS3, respectively, with pore sizes in the micro- (below 2 nm), meso- (2-50 nm), and macro- (above 50 nm) regions.

  2. Quicklime-induced changes of soil properties: Implications for enhanced remediation of volatile chlorinated hydrocarbon contaminated soils via mechanical soil aeration.

    Science.gov (United States)

    Ma, Yan; Dong, Binbin; He, Xiaosong; Shi, Yi; Xu, Mingyue; He, Xuwen; Du, Xiaoming; Li, Fasheng

    2017-04-01

    Mechanical soil aeration is used for soil remediation at sites contaminated by volatile organic compounds. However, the effectiveness of the method is limited by low soil temperature, high soil moisture, and high soil viscosity. Combined with mechanical soil aeration, quicklime has a practical application value related to reinforcement remediation and to its action in the remediation of soil contaminated with volatile organic compounds. In this study, the target pollutant was trichloroethylene, which is a volatile chlorinated hydrocarbon pollutant commonly found in contaminated soils. A restoration experiment was carried out, using a set of mechanical soil-aeration simulation tests, by adding quicklime (mass ratios of 3, 10, and 20%) to the contaminated soil. The results clearly indicate that quicklime changed the physical properties of the soil, which affected the environmental behaviour of trichloroethylene in the soil. The addition of CaO increased soil temperature and reduced soil moisture to improve the mass transfer of trichloroethylene. In addition, it improved the macroporous cumulative pore volume and average pore size, which increased soil permeability. As soil pH increased, the clay mineral content in the soils decreased, the cation exchange capacity and the redox potential decreased, and the removal of trichloroethylene from the soil was enhanced to a certain extent. After the addition of quicklime, the functional group COO of soil organic matter could interact with calcium ions, which increased soil polarity and promoted the removal of trichloroethylene. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. A POLYMER-CERAMIC COMPOSITE MEMBRANE FOR RECOVERING VOLATILE ORGANIC COMPOUNDS FROM WASTEWATERS BY PERVAPORATION

    Science.gov (United States)

    A composite membrane was constructed on a porous ceramic support from a block copolymer of styrene and butadiene (SBS). It was tested in a laboratory pervaporation apparatus for recovering volatile organic compounds (VOCs) such a 1,1,1-trichloroethane (TCA) and trichloroethylene ...

  4. Water stress and ripeness effects on the volatile composition of Cabernet Sauvignon wines.

    Science.gov (United States)

    Talaverano, Inmaculada; Ubeda, Cristina; Cáceres-Mella, Alejandro; Valdés, María Esperanza; Pastenes, Claudio; Peña-Neira, Álvaro

    2018-02-01

    Controlled water deficits affect grape berry physiology and the resulting wines, with volatile composition being the one of the affected parameters. However, there is a potential disconnect between aromatic maturity and sugar accumulation. Accordingly, the effects of three different water status levels over two growing seasons (2014 and 2015) and two different harvest dates on the aroma compounds from Cabernet Sauvignon wines were studied. Volatile compounds were determined using headspace solid phase microextraction coupled with gas chromatoghraphy/mass spectrometry. Around 45 volatile compounds were determined in the wines and, among these, esters were affected the most, presenting lower concentrations when the most restrictive water treatment was applied in both years. By contrast, volatile acids presented the highest concentrations when the lowest level of irrigation was applied. On the other hand, a delay in harvesting produced an increase in the total amount of volatile compounds in samples from the most restrictive water treatment. These results are coincident with a principal component analysis that indicated a great separation between years, deficit irrigation treatments and harvest dates. The results of the present study suggest that a low water supply had a negative effect on the aromatic potential of wines at a similar ripening stage. However, this effect could be countered by harvesting at a later date. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  5. Change in Color and Volatile Composition of Skim Milk Processed with Pulsed Electric Field and Microfiltration Treatments or Heat Pasteurization †

    Science.gov (United States)

    Chugh, Anupam; Khanal, Dipendra; Walkling-Ribeiro, Markus; Corredig, Milena; Duizer, Lisa; Griffiths, Mansel W.

    2014-01-01

    Non-thermal processing methods, such as pulsed electric field (PEF) and tangential-flow microfiltration (TFMF), are emerging processing technologies that can minimize the deleterious effects of high temperature short time (HTST) pasteurization on quality attributes of skim milk. The present study investigates the impact of PEF and TFMF, alone or in combination, on color and volatile compounds in skim milk. PEF was applied at 28 or 40 kV/cm for 1122 to 2805 µs, while microfiltration (MF) was conducted using membranes with three pore sizes (lab-scale 0.65 and 1.2 µm TFMF, and pilot-scale 1.4 µm MF). HTST control treatments were applied at 75 or 95 °C for 20 and 45 s, respectively. Noticeable color changes were observed with the 0.65 µm TFMF treatment. No significant color changes were observed in PEF-treated, 1.2 µm TFMF-treated, HTST-treated, and 1.4 µm MF-treated skim milk (p ≥ 0.05) but the total color difference indicated better color retention with non-thermal preservation. The latter did not affect raw skim milk volatiles significantly after single or combined processing (p ≥ 0.05), but HTST caused considerable changes in their composition, including ketones, free fatty acids, hydrocarbons, and sulfur compounds (p < 0.05). The findings indicate that for the particular thermal and non-thermal treatments selected for this study, better retention of skim milk color and flavor components were obtained for the non-thermal treatments. PMID:28234317

  6. Occupational exposure to gases, polycyclic aromatic hydrocarbons and volatile organic compounds in biomass-fired power plants.

    Science.gov (United States)

    Jumpponen, M; Rönkkömäki, H; Pasanen, P; Laitinen, J

    2013-01-01

    The combustion of fuels produces air pollutants in the form of gases, organic compounds, and particulate matter. However, although the environmental aspect of these agents has been examined, workers' exposure to them is still a neglected issue. The purpose of this study was to measure maintenance and ash removal workers' multiple exposures to gases, volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) during their work tasks in biomass-fired power plants. Our hygienic measurements revealed that carbon monoxide, nitric oxide, ammonia and sulfur dioxide were the most common gases that the workers were exposed to during their tasks. Their average concentrations were 0.45 ppm, 0.06 ppm, 0.11 ppm and 0.42 ppm, respectively. Phenanthrene and naphthalene were the most prominent PAHs. At the same sampling points, the most commonly found VOCs were aromatic and aliphatic hydrocarbons and turpentines. The calculated total PAH concentrations were less than 7% of benzo[a]pyrene's eight-hour occupational exposure limit, and the total VOC concentrations were below the Finnish reference value for the normal industrial level in all measured work tasks. The most evident health effect caused by multiple exposures to gases was upper respiratory track irritation, followed by the disruption of oxygen transport, and finally central nervous system disorders. We recommend powered air respirators with ABEK+P3 cartridges and carbon monoxide gas detectors as the minimum requirement for those working inside biomass-fired power plant boilers, and compressed air breathing apparatus as the best form of protection. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Profiling of volatile fragrant components in a mini-core collection of mango germplasms from seven countries.

    Directory of Open Access Journals (Sweden)

    Li Li

    Full Text Available Aroma is important in assessing the quality of fresh fruit and their processed products, and could provide good indicators for the development of local cultivars in the mango industry. In this study, the volatile diversity of 25 mango cultivars from China, America, Thailand, India, Cuba, Indonesia, and the Philippines was investigated. The volatile compositions, their relative contents, and the intervarietal differences were detected with headspace solid phase microextraction tandem gas chromatography-mass spectrometer methods. The similarities were also evaluated with a cluster analysis and correlation analysis of the volatiles. The differences in mango volatiles in different districts are also discussed. Our results show significant differences in the volatile compositions and their relative contents among the individual cultivars and regions. In total, 127 volatiles were found in all the cultivars, belonging to various chemical classes. The highest and lowest qualitative abundances of volatiles were detected in 'Zihua' and 'Mallika' cultivars, respectively. Based on the cumulative occurrence of members of the classes of volatiles, the cultivars were grouped into monoterpenes (16 cultivars, proportion and balanced (eight cultivars, and nonterpene groups (one cultivars. Terpene hydrocarbons were the major volatiles in these cultivars, with terpinolene, 3-carene, caryophyllene and α-Pinene the dominant components depending on the cultivars. Monoterpenes, some of the primary volatile components, were the most abundant aroma compounds, whereas aldehydes were the least abundant in the mango pulp. β-Myrcene, a major terpene, accounted for 58.93% of the total flavor volatile compounds in 'Xiaofei' (Philippens. γ-Octanoic lactone was the only ester in the total flavor volatile compounds, with its highest concentration in 'Guiya' (China. Hexamethyl cyclotrisiloxane was the most abundant volatile compound in 'Magovar' (India, accounting for 46.66% of

  8. Microbiology, biochemistry, and volatile composition of Tulum cheese ripened in goat's skin or plastic bags.

    Science.gov (United States)

    Hayaloglu, A A; Cakmakci, S; Brechany, E Y; Deegan, K C; McSweeney, P L H

    2007-03-01

    Tulum cheeses were manufactured from raw ewe's milk and ripened in goat's skin bags (tulums) or plastic containers to understand the effect of ripening container on the chemical composition, biochemistry, microbiology, and volatile composition of Tulum cheeses during 150 d of ripening. Chemical compositions of the cheeses ripened in tulums were significantly different and the moisture contents decreased rapidly in those cheeses because of the porous structure of the tulum. Higher microbial counts were detected in the cheeses ripened in plastic than in cheeses ripened in tulums. Differences in nitrogenous compounds and total free AA of the cheeses were not significant. Total concentrations of free AA in cheeses increased with age and Glu, Ala, Val, Leu, and Phe were the most abundant AA in the cheeses. Urea-PAGE of pH 4.6-insoluble fractions of the cheeses during ripening showed similar degradation patterns in all cheeses. Peptide profiles by reversed-phase HPLC of pH 4.6- and ethanol-soluble or ethanol-insoluble fractions of the cheeses revealed only minor differences in the concentrations of some peptides among the cheeses; however, age-related changes in peptide concentrations were significantly different among the cheeses. Cheeses were analyzed at 90 d of ripening for volatile compounds by solid-phase microextraction gas chromatography-mass spectrometry. One hundred volatile components were identified, including 11 acids, 16 esters, 12 methyl ketones, 7 aldehydes, 22 alcohols, 7 sulfur compounds, 6 terpenes, and 19 miscellaneous compounds. The main components were short-chain fatty acids, 2-butanone, diacetyl, and primary alcohols. Quantitative differences in several volatile compounds were evident among the cheeses. Cheeses ripened in tulums or plastic had similar aroma patterns, but the concentrations of some components were different.

  9. Study on off-odor volatiles of irradiated packaged raw pork

    International Nuclear Information System (INIS)

    Lin Ruotai; Geng Shengrong; Liu Yangmin

    2008-01-01

    Analysing the compositions of off-odor volatiles in irradiated refrigerated vacuum-packaged pork and research on its origin. First, the off-odor volatiles were collected by a cooled via in liquid nitrogen, then the main composition of off-odor volatiles were analyzed by gas chromatograph mass spectrometry (GC-MS). The main composition of off-odor volatiles are dimethyl disulfide, dimethyl sulfide, dimethyl trisulfide, methanethiol and S-methyl thioacetate. The off-odor volatiles come from irradiated cystine, methionine and VB1. The main composition of off-odor volatiles are S-containing compounds from irradiated S-containing amino acid and VB1

  10. Changes in volatile compound composition of Antrodia camphorata during solid state fermentation.

    Science.gov (United States)

    Xia, Yongjun; Zhang, Baorong; Li, Weijiang; Xu, Ganrong

    2011-10-01

    Although the volatiles present in mushrooms and fungi have been investigated by many researchers, including Antrodia camphorata in submerged fermentation, there are few data available regarding changes in volatile compounds during fermentation. Our research has revealed that solid state fermentation of A. camphorata is highly odiferous compared with submerged cultures and the odor changed with increasing culture time. Therefore the aim of this study was to investigate the changes in volatile compound composition of A. camphorata during solid state fermentation. Altogether, 124 major volatile compounds were identified. The volatile compounds produced by A. camphorata during growth in solid state fermentation were quite different. Oct-1-en-3-ol, octan-3-one and methyl 2-phenylacetate were predominant in exponential growth phase production, while the dominant volatiles produced in stationary phase were octan-3-one and methyl 2-phenylacetate. In stationary phase, lactone compounds in A. camphorata, such as 5-butyloxolan-2-one, 5-heptyloxolan-2-one, 6-heptyloxan-2-one, contributed greatly to peach and fruit-like flavor. Terpene and terpene alcohol compounds, such as 1-terpineol, L-linalool, T-cadinol, (E, E)-farnesol, β-elemene, cis-α-bisabolene and α-muurolene, made different contributions to herbal fresh aroma in A. camphorata. Nineteen volatile sesquiterpenes were detected from solid state fermentation of A. camphorata. The compounds 5-n-butyl-5H-furan-2-one, β-ionone, (-)-caryophyllene oxide, aromadendrene oxide, diepi-α-cedrene epoxide, β-elemene, α-selinene, α-muurolene, azulene, germacrene D, γ-cadinene and 2-methylpyrazine have not hitherto been reported in A. camphorata. The preliminary results suggest that the aroma-active compounds produced by A camphorata in solid state fermentation might serve as an important source of natural aroma compounds for the food and cosmetic industries or antibiotic activity compounds. The sesquiterpenes could be

  11. Broadly tunable mid-infrared VECSEL for multiple components hydrocarbon gas sensing

    Science.gov (United States)

    Rey, J. M.; Fill, M.; Felder, F.; Sigrist, M. W.

    2014-12-01

    A new sensing platform to simultaneously identify and quantify volatile C1 to C4 alkanes in multi-component gas mixtures is presented. This setup is based on an optically pumped, broadly tunable mid-infrared vertical-external-cavity surface-emitting laser (VECSEL) developed for gas detection. The lead-chalcogenide VECSEL is the key component of the presented optical sensor. The potential of the proposed sensing setup is illustrated by experimental absorption spectra obtained from various mixtures of volatile hydrocarbons and water vapor. The sensor has a sub-ppm limit of detection for each targeted alkane in a hydrocarbon gas mixture even in the presence of a high water vapor content.

  12. Determinants of the Sensory Quality of Półgęsek in Relation to Volatile Compounds and Chemical Composition

    Directory of Open Access Journals (Sweden)

    Nowicka Katarzyna

    2017-12-01

    Full Text Available The objective of this study was to determine the sensory quality of a specific Polish traditional product made from cured and then smoked goose meat (półgęsek in relation to its volatile compounds and chemical composition. In general, the examined samples contained 66.2% water, 12.2% fat, 17.9% protein, 1.8% connective tissue, and 2.3% NaCl. Moreover, 47 volatile compounds were identified and quantified. The typical decomposition products derived from lipid oxidation, amino acid degradation, carbohydrate fermentation and microbial esterification were the main volatiles detected in all the samples. The volatiles generated by the smoking process and the ones originating from spices were also observed. The results of the sensory evaluation indicated that all the samples of the analyzed products were characterized by a high overall quality. Results of the Principal Component Analysis (PCA showed, however, that specific groups of products have their own unique sensory profile. Additionally, the sensory analysis confirmed the significant role of the chemical composition and volatile compounds in the development of the overall quality of półgęsek.

  13. Process for making unsaturated hydrocarbons using microchannel process technology

    Science.gov (United States)

    Tonkovich, Anna Lee [Dublin, OH; Yuschak, Thomas [Lewis Center, OH; LaPlante, Timothy J [Columbus, OH; Rankin, Scott [Columbus, OH; Perry, Steven T [Galloway, OH; Fitzgerald, Sean Patrick [Columbus, OH; Simmons, Wayne W [Dublin, OH; Mazanec, Terry Daymo, Eric

    2011-04-12

    The disclosed invention relates to a process for converting a feed composition comprising one or more hydrocarbons to a product comprising one or more unsaturated hydrocarbons, the process comprising: flowing the feed composition and steam in contact with each other in a microchannel reactor at a temperature in the range from about 200.degree. C. to about 1200.degree. C. to convert the feed composition to the product, the process being characterized by the absence of catalyst for converting the one or more hydrocarbons to one or more unsaturated hydrocarbons. Hydrogen and/or oxygen may be combined with the feed composition and steam.

  14. Removal of light petroleum hydrocarbons from water sources using polypropylene and titanium dioxide nano-composite

    Directory of Open Access Journals (Sweden)

    H. Karyab

    2016-08-01

    Full Text Available Background: Petroleum hydrocarbons are the most important pollutants which threat human health and aquatics. Adsorbents are one of the common equipment in water pollution management; however, their applications have been associated with limitations. Objective: To evaluate the potential of polypropylene/titanium dioxide Nano-composite in adsorption of light petroleum hydrocarbons from water sources. Methods: This experimental study was conducted at school of health, Qazvin University of Medical Sciences in 2014-15. Activation of polypropylene fibers, with 1 cm length and 300 microns diameters, was achieved with wet heating. To synthesize of nano-composite the fibers were coated with nano-titanium dioxide with 20 nm diameter. The sonication was performed at 26 kHz and 100 W of power in 40ºc. The morphology of the fractured surfaces of impact specimens was examined by FESEM. The adsorption rate of petrol and gasoline, as surrogate of TPH, was evaluated in different retention time within polyamide mesh aperture diameter of 250 nm. Average of TPH adsorbing, per unit weight of adsorbent, were analyzed with analysis of variance and Scheffe post hoc tests. Findings: The FESEM micrographs showed that the dispersion of the nano-Tio2 particles was relatively good and only few aggregations exist. The maximum adsorption capacity of petrol and gasoline was obtained in 30 minute. The adsorption rate of gasoline was 6.49±0.10 g/g and oil was 7.01±0.13 g/g. Conclusion: According to the results and in comparison with commercial imported adsorbents, the synthesized Nano-composite had favorable performance. The results show that the polypropylene/Tio2 Nano-composite can be used effectively in light petroleum hydrocarbons removal from polluted water sources.

  15. Comprehensive GC–FID, GC–MS and FT-IR spectroscopic analysis of the volatile aroma constituents of Artemisia indica and Artemisia vestita essential oils

    Directory of Open Access Journals (Sweden)

    Manzoor A. Rather

    2017-05-01

    Full Text Available In the current study, the leaf volatile constituents of the essential oils of Artemisia indica Willd. and Artemisia vestita Wall were studied using a combination of capillary GC–FID, GC–MS and FT-IR (Fourier-Transform Infra-Red analytical techniques. The analysis led to the identification of 42 compounds in the essential oil of A. indica, representing 96.6% of the essential oil and the major components were found to be artemisia ketone (42.1%, germacrene D (8.6%, borneol (6.1% and cis-chrysanthenyl acetate (4.8%. The essential oil was dominated by the presence of oxygenated monoterpenes constituting 65.2% of the total oil composition followed by sesquiterpene hydrocarbons and monoterpene hydrocarbons constituting 15.7% and 10.7%, respectively of the total oil composition. The essential oil composition of A. vestita was found to contain a total of 18 components representing 94.2% of the total oil composition. The principal components were found to be 1,8-cineole (46.8%, (E-citral (13.7%, limonene (9.8%, α-phellandrene (6.4%, camphor (5.0%, (Z and (E-thujones (3.0% each. Oxygenated monoterpenes were the dominant group of terpenes in the essential oil constituting 73.1% of the total oil composition followed by monoterpene hydrocarbons (17.3%. The results of the current study reveal remarkable differences in the essential oil compositions of these two Artemisia species already reported in the literature from other parts of the globe.

  16. Composition of the volatile fraction of a sample of Brazilian green propolic and its phytotoxic activity.

    Science.gov (United States)

    Fernandes-Silva, Caroline C; Lima, Carolina A; Negri, Giuseppina; Salatino, Maria L F; Salatino, Antonio; Mayworm, Marco A S

    2015-12-01

    Propolis is a resinous material produced by honeybees, containing mainly beeswax and plant material. Despite the wide spectrum of biological activity of propolis, to our knowledge no studies have been carried out about phytotoxic properties of Brazilian propolis and its constituents. The aims of this study were to analyze the chemical composition and to evaluate the phytotoxic activity of the volatile fraction of a sample of Brazilian green propolis. Main constituents are the phenylpropanoid 3-prenylcinnamic acid allyl ester (26.3%) and the sesquiterpene spathulenol (23.4%). Several other sesquiterpenes and phenylpropanoids, in addition to linalool and α-terpineol (monoterpenes), were also detected. The activity of solutions of the volatile fraction at 1.0, 0.5 and 0.1% was tested on lettuce seeds and seedlings. The solution at 1% inhibited completely the seed germination and solutions at 0.1 and 0.5% reduced the germination rate index. The solution at 0.5% reduced the growth of the hypocotyl-radicle axis and the development of the cotyledon leaf. The chemical composition of the volatile fraction of this Brazilian green propolis is different from those previously described, and these results may contribute to a better understanding about the chemical variations in propolis. The volatile fraction of Brazilian green propolis influences both germination of seed lettuce and the growth of its seedlings, showing an phytotoxic potential. © 2014 Society of Chemical Industry.

  17. Advanced compositional gradient and compartmentalization analysis

    Energy Technology Data Exchange (ETDEWEB)

    Canas, Jesus A.; Petti, Daniela; Mullins, Oliver [Schlumberger Servicos de Petroleo Ltda., Rio de Janeiro, RJ (Brazil)

    2008-07-01

    Acquisition of hydrocarbons samples from the reservoir prior to oil or gas production is essential in order to design production strategies and production facilities. In addition, reservoir compartmentalization and hydrocarbon compositional grading magnify the necessity to map fluid properties vertically and laterally in the reservoir prior to production. Formation testers supply a wealth of information to observe and predict the state of fluids in hydrocarbon reservoirs, through detailed pressure and fluid analysis measurements. With the correct understanding of the state of fluids in the reservoirs, reserve calculations and adequate development plans can be prepared. Additionally, flow barriers may then be revealed. This paper describes a new Downhole Fluid Analysis technology (DFA) for improved reservoir management. DFA is a unique process that combines new fluid identification sensors, which allow real time monitoring of a wide range of parameters as GOR, fluid density, viscosity, fluorescence and composition (CH{sub 4}, C2- C5, C6 +, CO{sub 2}), free gas and liquid phases detection, saturation pressure, as well WBM and OBM filtrate differentiation and pH. This process is not limited to light fluid evaluation and we extended to heavy oil (HO) reservoirs analysis successfully. The combination of DFA Fluid Profiling with pressure measurements has shown to be very effective for compartmentalization characterization. The ability of thin barriers to hold off large depletion pressures has been established, as the gradual variation of hydrocarbon quality in biodegraded oils. In addition, heavy oils can show large compositional variation due to variations in source rock charging but without fluid mixing. Our findings indicates that steep gradients are common in gas condensates or volatile oils, and that biodegradation is more common in HO than in other hydrocarbons, which generate fluid gradients and heavy ends tars near the OWC, limiting the aquifer activity and

  18. Effect of hydrocarbons on plasma treatment of NOx

    Energy Technology Data Exchange (ETDEWEB)

    Penetrante, B.M.; Pitz, W.J.; Hsaio, M.C.; Merritt, B.T.; Vogtlin, G.E. [Lawrence Livermore National Lab., CA (United States)

    1997-12-31

    Lean burn gasoline engine exhausts contain a significant amount of hydrocarbons in the form of propene. Diesel engine exhausts contain little gaseous hydrocarbon; however, they contain a significant amount of liquid-phase hydrocarbons (known as the volatile organic fraction) in the particulates. The objective of this paper is to examine the fate of NO{sub x} when an exhaust gas mixture that contains hydrocarbons is subjected to a plasma. The authors will show that the hydrocarbons promote the oxidation of NO to NO{sub 2}, but not the reduction of NO to N{sub 2}. The oxidation of NO to NO{sub 2} is strongly coupled with the hydrocarbon oxidation chemistry. This result suggests that gas-phase reactions in the plasma alone cannot lead to the chemical reduction of NO{sub x}. Any reduction of NO{sub x} to N{sub 2} can only be accomplished through heterogeneous reactions of NO{sub 2} with surfaces or particulates.

  19. Analysis of the Volatile Profile of Core Chinese Mango Germplasm by Headspace Solid-Phase Microextraction Coupled with Gas Chromatography-Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Xiao-Wei Ma

    2018-06-01

    Full Text Available Despite abundant published research on the volatile characterization of mango germplasm, the aroma differentiation of Chinese cultivars remains unclear. Using headspace solid phase microextraction (HS-SPME coupled with gas chromatography–mass spectrometry (GC-MS, the composition and relative content of volatiles in 37 cultivars representing the diversity of Chinese mango germplasm were investigated. Results indicated that there are distinct differences in the components and content of volatile compounds among and within cultivars. In total, 114 volatile compounds, including 23 monoterpenes, 16 sesquiterpenes, 29 non-terpene hydrocarbons, 25 esters, 11 aldehydes, five alcohols and five ketones, were identified. The total volatile content among cultivars ranged from 211 to 26,022 μg/kg fresh weight (FW, with 123-fold variation. Terpene compounds were the basic background volatiles, and 34 cultivars exhibited abundant monoterpenes. On the basis of hierarchical cluster analysis (HCA and principal component analysis (PCA, terpinolene and α-pinene were important components constituting the aroma of Chinese mango cultivars. Most obviously, a number of mango cultivars with high content of various aroma components were observed, and they can serve as potential germplasms for both breeding and direct use.

  20. AGRONOMIC OPTIMIZATION FOR PHYTOREMEDIATION OF POLYCYCLIC AROMATIC HYDROCARBONS

    Science.gov (United States)

    Phytoremediation is a low-cost method of using plants to degrade, volatilize or sequester organic and metal pollutants that has been used in efforts to remediate sites contaminated with polycyclic aromatic hydrocarbon (PAH) refinery wastes. Non-native plant species aggressivel...

  1. Investigating the Variation of Volatile Compound Composition in Maotai-Flavoured Liquor During Its Multiple Fermentation Steps Using Statistical Methods

    Directory of Open Access Journals (Sweden)

    Zheng-Yun Wu

    2016-01-01

    Full Text Available The use of multiple fermentations is one of the most specific characteristics of Maotai-flavoured liquor production. In this research, the variation of volatile composition of Maotai-flavoured liquor during its multiple fermentations is investigated using statistical approaches. Cluster analysis shows that the obtained samples are grouped mainly according to the fermentation steps rather than the distillery they originate from, and the samples from the first two fermentation steps show the greatest difference, suggesting that multiple fermentation and distillation steps result in the end in similar volatile composition of the liquor. Back-propagation neural network (BNN models were developed that satisfactorily predict the number of fermentation steps and the organoleptic evaluation scores of liquor samples from their volatile compositions. Mean impact value (MIV analysis shows that ethyl lactate, furfural and some high-boiling-point acids play important roles, while pyrazine contributes much less to the improvement of the flavour and taste of Maotai-flavoured liquor during its production. This study contributes to further understanding of the mechanisms of Maotai-flavoured liquor production.

  2. Constructed wetlands for treatment of dissolved phase hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Moore, B J; Ross, S D [Komex International, Calgary, AB (Canada); Gibson, D [Calgary Univ., AB (Canada); Hardisty, P E [Komex Clarke Bond, Bristol (United Kingdom)

    1999-01-01

    The use of constructed wetlands as an alternative to conventional treatment of condensate-contaminated groundwater was studied. In 1997 a pilot scale wetland was constructed and implemented at the Gulf Strachan Gas Processing Plant to determine its ability in treating extracted groundwater contaminated with natural gas condensates. This paper presented the results of hydrocarbon removal efficiency, hydrocarbon removal mechanisms, winter operation, and the effect of hydrocarbons on vegetation health. The inflow water to the wetland contains 15 to 20 mg/L of C[sub 5]-C[sub 10] hydrocarbons, including 50 per cent BTEX compounds. During the summer months, hydrocarbon removal efficiency was 100 per cent, but decreased to 60 and 30 per cent in the spring and late fall, respectively. The hydrocarbons not removed in the wetland were eventually removed along the outflow channel. Temperature was determined to be an important factor in the variable removal rates, particularly when there is no aeration. The main hydrocarbon removal mechanisms appear to be volatilization, biodegradation and dilution. At present, plant uptake is not a factor. 12 refs., 1 tab., 3 figs.

  3. Constructed wetlands for treatment of dissolved phase hydrocarbons

    International Nuclear Information System (INIS)

    Moore, B.J.; Ross, S.D.; Gibson, D.; Hardisty, P.E.

    1999-01-01

    The use of constructed wetlands as an alternative to conventional treatment of condensate-contaminated groundwater was studied. In 1997 a pilot scale wetland was constructed and implemented at the Gulf Strachan Gas Processing Plant to determine its ability in treating extracted groundwater contaminated with natural gas condensates. This paper presented the results of hydrocarbon removal efficiency, hydrocarbon removal mechanisms, winter operation, and the effect of hydrocarbons on vegetation health. The inflow water to the wetland contains 15 to 20 mg/L of C 5 -C 10 hydrocarbons, including 50 per cent BTEX compounds. During the summer months, hydrocarbon removal efficiency was 100 per cent, but decreased to 60 and 30 per cent in the spring and late fall, respectively. The hydrocarbons not removed in the wetland were eventually removed along the outflow channel. Temperature was determined to be an important factor in the variable removal rates, particularly when there is no aeration. The main hydrocarbon removal mechanisms appear to be volatilization, biodegradation and dilution. At present, plant uptake is not a factor. 12 refs., 1 tab., 3 figs

  4. The effect of prolonged flooding of an oil deposit on the special composition and the activity of hydrocarbon-oxidizing microflora

    Energy Technology Data Exchange (ETDEWEB)

    Berdichevskaya, M V

    1982-07-01

    The special composition of hydrocarbon-oxidizing bacteria was studied in terrigenous and carbonate oil-bearing strata from several deposits of the Permian Cis-Ural region. We isolated 43 strains and assigned them to the following genera: Mycobacterium, Micrococcus, Brevibacterium, Corynebacterium, Flavobacterium, Achromobacter and Pseudomonas. The special composition of the hydrocarbon-oxidizing microflora was shown to depend on the flooding of an oil stratum, as a result of which the ecological environment in a deposit changed. Gram-positive coryneform bacteria were found in stratal salinized waters and in diluted stratal waters. Gram-negative hydrocarbon-oxidizing bacteria were isolated from pumped-in river waters and from stratal waters diluted by 70-100% as the result of flooding. The metabolic activity of Corynebacterium fascians (2 strains), Mycobacterium rubrum (1 strain), Pseudomonas mira (1 strain) and Flavobacterium perigrinum (1 strain) was assayed in stratal waters with different concentrations of salts. The coryneform hydrocarbon-oxidizing bacteria were shown to be very halotolerant as the result of adaptation; that is why the incidence of these microorganisms is very great in highly mineralized stratal water of oil deposits.

  5. Volatile oil composition of Carthamus Tinctorius L. flowers grown in Kazakhstan.

    Science.gov (United States)

    Turgumbayeva, Aknur Amanbekovna; Ustenova, Gulbaram Omargazieva; Yeskalieva, Balakyz Kymyzgalievna; Ramazanova, Bakyt Amanullovna; Rahimov, Kairolla Duysenbayevich; Aisa, Hajiakbar; Juszkiewicz, Konrad T

    2018-03-14

    Carthamus tinctorius L. is commonly known as Safflower. C. tinctorius extracts and oil are important in drug development with numerous pharmacological activities in the world. This plant is cultivated mainly for its seed which is used as edible oil. For a long time, C. tinctorius has been used in traditional medicines as a purgative, analgesic, antipyretic and an antidote to poisoning. It is a useful plant in painful menstrual problems, post-partum haemorrhage and osteoporosis. The subject of this study is the seeds of Kazakhstan species of 'Akmai' safflower, collected in the flowering stage in Southern Kazakhstan. Volatile oil was carry out to study the component composition of Kazakhstan 'AkMai' safflower flowers. Pale yellow oily extracts were obtain by varying the process parameters. The volatile oil obtained by hydrodistillation of the petals Carthamus tinctorius L. was analyzed by gas chromatography/mass spectrometry (GC/MS). The yield of the oil was 0.175 % (v/w). 20 compounds representing 99.81% of the oil were characterized. The volatile oil was found to be rich in undecanoic acid, octane, 2-nonen -1-ol, hexadecanal, dodecanal, dec-2-en-1-ol, nonanoic acid, tetradecanoic acid, 2 pentadecanone, 6,10,14-trimethyl, 1,2-benzenedicarboxylic acid, isobutyl-beta-phenylpropionate, 1.3-cyclohexadiene, myrtenoic acid, octadecanoic acid, heneicosanoic acid, 2(3H)-furanone, 4,4-dipropylheptane, hexcosane,1-eicosanol, as well as heptocosane. Volatile oil from the flowers of the Kazakhstan safflower species 'Ak-Mai' were investigated by GC/MS which allowed the detection of 20 compounds. Biologically active complex of the flower of the Kazakhstan safflower species 'Ak-Mai' was released for the first time by using this oil.

  6. Thermophilic slurry-phase treatment of petroleum hydrocarbon waste sludges

    International Nuclear Information System (INIS)

    Castaldi, F.J.; Bombaugh, K.J.; McFarland, B.

    1995-01-01

    Chemoheterotrophic thermophilic bacteria were used to achieve enhanced hydrocarbon degradation during slurry-phase treatment of oily waste sludges from petroleum refinery operations. Aerobic and anaerobic bacterial cultures were examined under thermophilic conditions to assess the effects of mode of metabolism on the potential for petroleum hydrocarbon degradation. The study determined that both aerobic and anaerobic thermophilic bacteria are capable of growth on petroleum hydrocarbons. Thermophilic methanogenesis is feasible during the degradation of hydrocarbons when a strict anaerobic condition is achieved in a slurry bioreactor. Aerobic thermophilic bacteria achieved the largest apparent reduction in chemical oxygen demand, freon extractable oil, total and volatile solid,s and polycyclic aromatic hydrocarbons (PAHs) when treating oily waste sludges. The observed shift with time in the molecular weight distribution of hydrocarbon material was more pronounced under aerobic metabolic conditions than under strict anaerobic conditions. The changes in the hydrocarbon molecular weight distribution, infrared spectra, and PAH concentrations during slurry-phase treatment indicate that the aerobic thermophilic bioslurry achieved a higher degree of hydrocarbon degradation than the anaerobic thermophilic bioslurry during the same time period

  7. Syngas Conversion to Gasoline-Range Hydrocarbons over Pd/ZnO/Al2O3 and ZSM-5 Composite Catalyst System

    Energy Technology Data Exchange (ETDEWEB)

    Dagle, Robert A.; Lizarazo Adarme, Jair A.; Lebarbier, Vanessa MC; Gray, Michel J.; White, James F.; King, David L.; Palo, Daniel R.

    2014-07-01

    A composite Pd/ZnO/Al2O3-HZSM-5 (Si/Al=40) catalytic system was evaluated for the synthesis of gasoline-range hydrocarbons directly from synthesis gas. Bifunctional catalyst comprising PdZn metal and acid sites present the required catalytically active sites necessary for the methanol synthesis, methanol dehydration, and methanol-to-gasoline reactions. This system provides a unique catalytic pathway for the production of liquid hydrocarbons directly from syngas. However, selectivity control is difficult and poses many challenges. The composite catalytic system was evaluated under various process conditions. Investigated were the effects of temperature (310-375oC), pressure (300-1000 psig), time-on-stream (50 hrs), and gas-hour space velocity (740-2970 hr-1), using a H2/CO molar syngas ratio of 2.0. By operating at the lower end of the temperature range investigated, liquid hydrocarbon formation was favored, as was decreased amounts of undesirable light hydrocarbons. However, lower operating temperatures also facilitated undesirable CO2 formation via the water-gas shift reaction. Higher operating pressures slightly favored liquid synthesis. Operating at relatively low pressures (e.g. 300 psig) was made possible, whereas for methanol synthesis alone higher pressure are usually required to achieve similar conversion levels (e.g. 1000 psig). Thermodynamic constraints on methanol synthesis are eased by pushing the equilibrium through hydrocarbon formation. Catalytic performance was also evaluated by altering Pd and Zn composition of the Pd/ZnO/Al2O3 catalyst. Of the catalysts and conditions tested, selectivity toward liquid hydrocarbon was highest when using a 5% Pd metal loading and Pd/Zn molar ratio of 0.25 and mixed with HZMS-5, operating at 310oC and 300 psig, CO conversion was 43 % and selectivity (carbon weight basis) to hydrocarbons was 49 wt. %. Of the hydrocarbon fraction, 44wt. % was in the C5-C12 liquid product range and consisted primarily of aromatic

  8. The bulk isotopic composition of hydrocarbons in subaerial volcanic-hydrothermal emissions from different tectonic settings

    Science.gov (United States)

    Fiebig, J.; Tassi, F.; Vaselli, O.; Viveiros, M. F.; Silva, C.; Lopez, T. M.; D'Alessandro, W.; Stefansson, A.

    2015-12-01

    Assuming that methane and its higher chain homologues derive from a common source, carbon isotope patterns have been applied as a criterion to identify occurrences of abiogenic hydrocarbons. Based on these, it has been postulated that abiogenic hydrocarbon production occurs within several (ultra)mafic environments. More evolved volcanic-hydrothermal systems may also provide all the prerequisites necessary for abiogenic hydrocarbon production, such as availability of inorganic CO2, hydrogen and heat. We have investigated the chemical and isotopic composition of n-alkanes contained within subaerial hydrothermal discharges emitted from a range of hot spot, subduction and rift-related volcanoes to determine the origin of hydrocarbons in these systems. Amongst these are Nisyros (Greece), Vesuvio, Campi Flegrei, Ischia, Pantelleria and Vulcano (all Italy), Mt. Mageik and Trident (USA), Copahue (Argentina), Teide (Spain), Furnas and Fogo (Portugal). The carbon isotopic composition of methane emitted from these sites varies from -65 to -8‰ , whereas δ13C of ethane and propane exhibit a much narrower variation from -17‰ to -31‰. Methane that occurs most enriched in 13C is also characterized by relatively positive δD values ranging up to -80‰. Carbon isotope reversals between methane and ethane are only observed for locations exhibiting δ13C-CH4 values > -20‰, such as Teide, Pantelleria, Trident and Furnas. At Furnas, δ13C-CH4 varies by 50‰ within a relatively short distance of <50m between two vents, whereas δ13C-C2H6 varies by less than 2‰ only. For some of the investigated locations apparent carbon isotopic temperatures between methane and CO2 are in agreement with those derived from gas concentration geothermometers. At these locations methane, however seems to be in disequilibrium with ethane and propane. These findings imply that methane on the one hand and the C2+ hydrocarbons on the other hand often might derive from distinct sources.

  9. Analytical Characterization of Volatile Active Principles from the ...

    African Journals Online (AJOL)

    After the extraction of volatile active principles in water, analytical separation and quantitative determination using a GC/MS technique was performed. The compounds detected, are belonging to the following classes: aldehydes, ketones, aromatic hydrocarbons and alcohols. South African Journal of Chemistry Vol.55 2002: ...

  10. Fates, Budgets, and Health Implications of Macondo Spill Volatile Hydrocarbons in the Ocean and Atmosphere of the Gulf of Mexico

    Science.gov (United States)

    Leifer, I.; Barletta, B.; Blake, D. R.; Blake, N. J.; Bradley, E. S.; Meinardi, S.; Lehr, B.; Luyendyk, B. P.; Roberts, D. A.; Rowland, F. S.

    2010-12-01

    The Macondo Oil Spill released unprecedented oil and gas to the ocean, estimated at 63000 bbl/day, which dispersed and dissolved during rise (Technical Flow Rate Team Report, 2010); yet, most of the oil reached the sea surface as oil slicks that then evolved due to weathering and dispersant application (Mass Balance Report, 2010). Remote sensing (near infrared imaging spectrometry) allowed quantification of thick surface oil, values of which were incorporated into an overall oil budget calculation. Remote sensing data, atmospheric samples, and numerical modeling, strongly suggest significant volatile loss during rise, yet measured atmospheric concentrations were high. Scaling atmospheric measurements to the total oil spill implies very high, extensive, and persistent levels of atmospheric petroleum hydrocarbon exposure with strong health implications to on-site workers and to coastal residents from wind advection.

  11. Characterization of Volatile Compounds with HS-SPME from Oxidized n-3 PUFA Rich Oils via Rancimat Tests.

    Science.gov (United States)

    Yang, Kai-Min; Cheng, Ming-Ching; Chen, Chih-Wei; Tseng, Chin-Yin; Lin, Li-Yun; Chiang, Po-Yuan

    2017-02-01

    Algae oil and fish oil are n-3 PUFA mainstream commercial products. The various sources for the stability of n-3 PUFA oxidation are influenced by the fatty acid composition, extraction and refined processing. In this study, the oil stability index (OSI) occurs within 2.3 to 7.6 hours with three different n-3 PUFA rich oil. To set the OSI in the Rancimat test as the oil stability limit and observed various degrees of oxidation (0, 25, 50, 75, 100 and 125%). The volatile oxidation compounds were analyzed via headspace-solid phase microextraction (HS-SPME) and GC/MS. We detected 51 volatile compound variations during the oxidation, which were composed of aldehydes, hydrocarbons, cyclic compounds, alcohols, benzene compounds, ketones, furans, ester and pyrrolidine. The off-flavor characteristics can be strongly influenced by the synergy effects of volatile oxidation compounds. Chemometric analysis (PCA and AHC) was applied to identify the sensitive oxidation marker compounds, which included a (E,E)-2,4-heptadienal appropriate marker, via lipid oxidation in the n-3 PUFA rich oil.

  12. Effect of different drying techniques on bioactive components, fatty acid composition, and volatile profile of robusta coffee beans.

    Science.gov (United States)

    Dong, Wenjiang; Hu, Rongsuo; Chu, Zhong; Zhao, Jianping; Tan, Lehe

    2017-11-01

    This study investigated the effect of different drying techniques, namely, room-temperature drying (RTD), solar drying (SD), heat-pump drying (HPD), hot-air drying (HAD), and freeze drying (FD), on bioactive components, fatty acid composition, and the volatile compound profile of robusta coffee beans. The data showed that FD was an effective method to preserve fat, organic acids, and monounsaturated fatty acids. In contrast, HAD was ideal for retaining polyunsaturated fatty acids and amino acids. Sixty-two volatile compounds were identified in the differently dried coffee beans, representing 90% of the volatile compounds. HPD of the coffee beans produced the largest number of volatiles, whereas FD resulted in the highest volatile content. A principal component analysis demonstrated a close relationship between the HPD, SD, and RTD methods whereas the FD and HAD methods were significantly different. Overall, the results provide a basis for potential application to other similar thermal sensitive materials. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. A numerical solution to three-dimensional multiphase transport of volatile organic compounds in unsaturated soils -- with an application to the remedial method of in-situ volatilization

    International Nuclear Information System (INIS)

    Filley, T.; Tomasko, D.

    1992-04-01

    Part I of this paper presents the development and application of a numerical model for determining the fate and transport of volatile organic compounds (VOCS) in the unsaturated zone resulting from forced volatilization and gaseous advection-dispersion of organic vapor in a multipartitioned three-dimensional environment. The model allows for single-component transport in the gas and water phases. The hydrocarbon is assumed to be in specific retention and, therefore, immobile. Partitioning of the hydrocarbon between the oil, water, gas, and soil is developed as rate-limited functions that are incorporated into sink/source terms in the transport equations. The code for the model was developed specifically to investigate in-situ volatilization (ISV) remedial strategies, predict the extent of cleanup from information obtained at a limited number of measurement locations, and to help design ISV remedial systems. Application of the model is demonstrated for a hypothetical one-dimensional ISV system. Part II of this paper will present the analysis of an existing ISV system using the full three-dimensional capability of the model

  14. Inverse Opal Photonic Crystals as an Optofluidic Platform for Fast Analysis of Hydrocarbon Mixtures.

    Science.gov (United States)

    Xu, Qiwei; Mahpeykar, Seyed Milad; Burgess, Ian B; Wang, Xihua

    2018-06-13

    Most of the reported optofluidic devices analyze liquid by measuring its refractive index. Recently, the wettability of liquid on various substrates has also been used as a key sensing parameter in optofluidic sensors. However, the above-mentioned techniques face challenges in the analysis of the relative concentration of components in an alkane hydrocarbon mixture, as both refractive indices and wettabilities of alkane hydrocarbons are very close. Here, we propose to apply volatility of liquid as the key sensing parameter, correlate it to the optical property of liquid inside inverse opal photonic crystals, and construct powerful optofluidic sensors for alkane hydrocarbon identification and analysis. We have demonstrated that via evaporation of hydrocarbons inside the periodic structure of inverse opal photonic crystals and observation of their reflection spectra, an inverse opal film could be used as a fast-response optofluidic sensor to accurately differentiate pure hydrocarbon liquids and relative concentrations of their binary and ternary mixtures in tens of seconds. In these 3D photonic crystals, pure chemicals with different volatilities would have different evaporation rates and can be easily identified via the total drying time. For multicomponent mixtures, the same strategy is applied to determine the relative concentration of each component simply by measuring drying time under different temperatures. Using this optofluidic sensing platform, we have determined the relative concentrations of ternary hydrocarbon mixtures with the difference of only one carbon between alkane hydrocarbons, which is a big step toward detailed hydrocarbon analysis for practical use.

  15. Application of backflush and micro-flow techniques to the analysis of C5-C13 hydrocarbons in crude oils and its geochemical significance

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    An Agilent 6890N GC equipped with both FID and Agilent 5975 MSD analyzer has been employed to analyze C5-C13 hydrocarbon fractions of crude oils. A technical combination of program temperature volatilizer injection, backflush and micro-flow controller afforded a fine separation of C5-C13 compounds on a PONA column with the heavy part of crude oils being cut off before entering the analytical column. Both GC-FID chromatogram and GC-MS mass chromatograrns (MID and full scan) could be obtained at the same time. The retension time differences of nC6-nC13 alkanes between GC and TIC were in the range of 0.02-0. 58 minutes. Totally 286 peaks have been assigned group compositions. Results on 8 typical oil samples from CNPC Key Laboratory Crude Oil Library showed that the characteristics of C6-C13 hydrocarbon group composition could be used in oil-oil correlation studies.

  16. Genetic architecture of natural variation in cuticular hydrocarbon composition in Drosophila melanogaster.

    Science.gov (United States)

    Dembeck, Lauren M; Böröczky, Katalin; Huang, Wen; Schal, Coby; Anholt, Robert R H; Mackay, Trudy F C

    2015-11-14

    Insect cuticular hydrocarbons (CHCs) prevent desiccation and serve as chemical signals that mediate social interactions. Drosophila melanogaster CHCs have been studied extensively, but the genetic basis for individual variation in CHC composition is largely unknown. We quantified variation in CHC profiles in the D. melanogaster Genetic Reference Panel (DGRP) and identified novel CHCs. We used principal component (PC) analysis to extract PCs that explain the majority of CHC variation and identified polymorphisms in or near 305 and 173 genes in females and males, respectively, associated with variation in these PCs. In addition, 17 DGRP lines contain the functional Desat2 allele characteristic of African and Caribbean D. melanogaster females (more 5,9-C27:2 and less 7,11-C27:2, female sex pheromone isomers). Disruption of expression of 24 candidate genes affected CHC composition in at least one sex. These genes are associated with fatty acid metabolism and represent mechanistic targets for individual variation in CHC composition.

  17. Volatile components from mango (Mangifera indica L.) cultivars.

    Science.gov (United States)

    Pino, Jorge A; Mesa, Judith; Muñoz, Yamilie; Martí, M Pilar; Marbot, Rolando

    2005-03-23

    The volatile components of 20 mango cultivars were investigated by means of simultaneous distillation-extraction, GC, and GC-MS. Three hundred and seventy-two compounds were identified, of which 180 were found for the first time in mango fruit. The total concentration of volatiles was approximately 18-123 mg/kg of fresh fruit. Terpene hydrocarbons were the major volatiles of all cultivars, the dominant terpenes being delta-3-carene (cvs. Haden, Manga amarilla, Macho, Manga blanca, San Diego, Manzano, Smith, Florida, Keitt, and Kent), limonene (cvs. Delicioso, Super Haden, Ordonez, Filipino, and La Paz), both terpenes (cv. Delicia), terpinolene (cvs. Obispo, Corazon, and Huevo de toro), and alpha-phellandrene (cv. Minin). Other qualitative and quantitative differences among the cultivars could be demonstrated.

  18. Volatile organic compound measurements in the California/Mexico border region during SCOS97

    International Nuclear Information System (INIS)

    Zielinska, B.; Sagebiel, J.; Harshfield, G.; Pasek, R.

    2001-01-01

    Measurements of volatile organic compounds (VOC) were carried out in the California/Mexico border region during the Southern California Ozone Study in the summer of 1997 (SCOS97). Integrated 3-h samples were collected in Rosarito (south of Tijuana, Mexico) and in Mexicali during intensive operational periods (IOP), twice per IOP day. VOC were collected using stainless-steel 6-l canisters; carbonyl compounds were collected using 2,4-dinitrophenylhydrazine (DNPH) impregnated C18 SepPak cartridges. The canister samples were analyzed for speciated volatile hydrocarbons (C 2 -C 12 ), CO, CO 2 , CH 4 , methyl t-butyl ether (MTBE), and halogenated hydrocarbons. DNPH-impregnated cartridges were analyzed for 14 C 1 -C 7 carbonyl compounds. The concentrations of all species were higher at Mexicali than in Rosarito. A good correlation between total non-methane hydrocarbons (TNMHC), CO, and other pollutants associated with motor vehicle emissions observed for Mexicali indicates that the main source of TNMHC at this site is vehicular traffic

  19. Volatiles from solids

    Energy Technology Data Exchange (ETDEWEB)

    Loughrey, C T

    1939-08-24

    To remove volatiles from solids, such as oil shale, gases, and/or vapours are passed through a mass of the materials, the vapours and gases separated, and the vapours condensed. The volatile-containing solid materials are fed to a retort, and a shaft is driven to rotate an impeller so as to displace the liquid and create a vortex tube, which draws in gas from the atmosphere through an intake, twyer, interstices in the material in the retort, a conduit, chamber, tubes, another chamber and cylinder. This gas is carried outwardly and upwardly by the vortices in the liquid and is carried to discharge through three conduits. The vapours entrained by the gas are part condensed in the liquid and the remainder directed to a condenser. Steam may be delivered to the twyer through a nozzle of a pipe, with or without air, and combustible hydrocarbon fuel may be fed through the burner nozzle or solid fuel may be directed from feeder and combusted in the twyer.

  20. Volatile composition and sensory profile of shiitake mushrooms as affected by drying method.

    Science.gov (United States)

    Politowicz, Joanna; Lech, Krzysztof; Lipan, Leontina; Figiel, Adam; Carbonell-Barrachina, Ángel A

    2018-03-01

    One of the best preservation method for long-term storage is drying. In this work, the influence of different drying methods on aroma and sensory profile of shiitake mushroom was evaluated. The drying methods tested were: convective drying (CD), freeze-drying (FD), vacuum-microwave drying (VMD), and a combination of convective pre-drying and vacuum-microwave finish-drying (CPD-VMFD). The volatile composition of fresh and dried shiitake mushrooms was analysed by SPME, GC-MS and GC-FID, and showed the presence of 71 volatile compounds, most of them present in all dried samples but with quantitative variation. The major volatile compounds in fresh shiitake were 1-octen-3-ol (20.2%), 2-octanone (20.7%), 1,2,4-trithiolane (9.8%), and 1,2,3,5,6-pentathiepane (8.2%). Drying of shiitake mushrooms caused significant losses of C8 compounds and cyclic sulfur compounds, such as 1,2,4-trithiolane (V31) and 1,2,4,5-tetrathiane (V57). Samples dried at CD 80 °C implied a relative short drying time (120 min), had the highest contents of total volatiles (1594 μg 100 g -1 ) and cyclic sulfur compounds (e.g. V57 126 μg 100 g -1 ), and the highest intensity of most of the key positive sensory attributes, such as inner colour (7.0), fresh shiitake flavour (6.7), and sponginess (6.2). The best dehydration methods, resulting in the highest total concentrations of volatile compounds and high intensity of key sensory attributes were FD (if vacuum and liquid nitrogen facilities are available) and CD at 80 °C (for companies with vacuum and liquid nitrogen facilities). © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  1. [Influence of liquid or solid culture conditions on the volatile components of mycelia of Isariacateinannulata].

    Science.gov (United States)

    Zhang, Delong; Wang, Xiaodong; Lu, Ruili; Li, Kangle; Hu, Fenglin

    2011-12-01

    To determine the volatile components of mycelia of Isaria cateinannulata cultured under different culture conditions, and to analyze the relationships between the culture conditions and volatile metabolites. Mycelia were cultured in solid plates with SDAY medium and liquid shake flasks with SDY medium. The culture conditions were at 25 degrees C and 8 days. Volatile components in the mycelia of I. cateinannulata were extracted with simultaneous distillation extraction and analyzed by gas chromatography-mass spectrometry. Alkenes, alkanes, heterocyclic and polycyclic aromatic hydrocarbons (PAH) were existed abundantly both in the mycelia of liquid and solid cultures, but the kinds and relative concentrations of the volatile components in mycelia of liquid and solid cultures were very different. Forty-one compounds were identified from the mycelia of solid culture and 32 compounds were identified from the mycelia of liquid culture. Esters, quinones and oximes were only found in solid cultured mycelia whereas carboxylic acids were only discovered in the mycelia of liquid culture. At the same time, mycelia of liquid culture contained much more phenols. The most abundant compounds in mycelia of liquid and solid cultures were hydrocarbons. The volatile extracts of solid cultured mycelia contained 57.6% alkenes and 9.19% alkanes. The volatile extracts of liquid cultured mycelia contained 7.85% alkenes and 22.4% alkanes. Liquid or solid culture conditions influenced the volatile components of mycelia of I. cateinannulata.

  2. Headspace Analysis of Volatile Compounds Coupled to Chemometrics in Leaves from the Magnoliaceae Family

    Directory of Open Access Journals (Sweden)

    Mohamed A. Farag

    2015-01-01

    Full Text Available Headspace volatile analysis has been used for volatiles profiling in leaves of 4 Magnolia species with a total of 75 compounds were identified. Monterpene hydrocarbons dominated the volatile blend of M. calophylla (86%, M. acuminata (78%, M. virginiana (70% and M. grandiflora (47% with b -pinene and b -ocimene occurring in the largest amounts, whereas sesquiterpenes were the most abundant compounds in M. grandiflora (39%. High levels of oxygenated compounds were only found in M. virginiana volatile blend (11.4% with 2-phenylethyl alcohol as major component. Hierarchical cluster analysis performed on volatiles content revealed the close relationship between M. acuminata and M. calophylla.

  3. Wintertime hygroscopicity and volatility of ambient urban aerosol particles

    Science.gov (United States)

    Enroth, Joonas; Mikkilä, Jyri; Németh, Zoltán; Kulmala, Markku; Salma, Imre

    2018-04-01

    Hygroscopic and volatile properties of atmospheric aerosol particles with dry diameters of (20), 50, 75, 110 and 145 nm were determined in situ by using a volatility-hygroscopicity tandem differential mobility analyser (VH-TDMA) system with a relative humidity of 90 % and denuding temperature of 270 °C in central Budapest during 2 months in winter 2014-2015. The probability density function of the hygroscopic growth factor (HGF) showed a distinct bimodal distribution. One of the modes was characterised by an overall mean HGF of approximately 1.07 (this corresponds to a hygroscopicity parameter κ of 0.033) independently of the particle size and was assigned to nearly hydrophobic (NH) particles. Its mean particle number fraction was large, and it decreased monotonically from 69 to 41 % with particle diameter. The other mode showed a mean HGF increasing slightly from 1.31 to 1.38 (κ values from 0.186 to 0.196) with particle diameter, and it was attributed to less hygroscopic (LH) particles. The mode with more hygroscopic particles was not identified. The probability density function of the volatility GF (VGF) also exhibited a distinct bimodal distribution with an overall mean VGF of approximately 0.96 independently of the particle size, and with another mean VGF increasing from 0.49 to 0.55 with particle diameter. The two modes were associated with less volatile (LV) and volatile (V) particles. The mean particle number fraction for the LV mode decreased from 34 to 21 % with particle diameter. The bimodal distributions indicated that the urban atmospheric aerosol contained an external mixture of particles with a diverse chemical composition. Particles corresponding to the NH and LV modes were assigned mainly to freshly emitted combustion particles, more specifically to vehicle emissions consisting of large mass fractions of soot likely coated with or containing some water-insoluble organic compounds such as non-hygroscopic hydrocarbon-like organics. The hygroscopic

  4. Changes in volatile composition and sensory attributes of wines during alcohol content reduction.

    Science.gov (United States)

    Longo, Rocco; Blackman, John W; Torley, Peter J; Rogiers, Suzy Y; Schmidtke, Leigh M

    2017-01-01

    A desirable sensory profile is a major consumer driver for wine acceptability and should be considered during the production of reduced-alcohol wines. Although various viticultural practices and microbiological approaches show promising results, separation technologies such as membrane filtration, in particular reverse osmosis and evaporative perstraction, in addition to vacuum distillation, represent the most common commercial methods used to produce reduced-alcohol wine. However, ethanol removal from wine can result in a significant loss of volatile compounds such as esters (ethyl octanoate, ethyl acetate, isoamyl acetate) that contribute positively to the overall perceived aroma. These losses can potentially reduce the acceptability of the wine to consumers and decrease their willingness to purchase wines that have had their alcohol level reduced. The change in aroma as a result of the ethanol removal processes is influenced by a number of factors: the type of alcohol reduction process; the chemical-physical properties (volatility, hydrophobicity, steric hindrance) of the aroma compounds; the retention properties of the wine non-volatile matrix; and the ethanol level. This review identifies and summarises possible deleterious influences of the dealcoholisation process and describes best practice strategies to maintain the original wine composition. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  5. Chemical Composition of the Volatile Components of Tropaeolum majus L. (Garden Nasturtium from North Western Algeria

    Directory of Open Access Journals (Sweden)

    B. BENYELLES

    2015-11-01

    Full Text Available Essential oil from Tropaeolum majus L. aerial parts, a plant native to North Western Algeria, was obtained by hydrodistillation. The oil volatile components were identified by a combination of gas chromatography/flame ionization detection (GC/FID, GC-mass spectrometry (GC-MS techniques, and NMR spectroscopy. Nine components representing 92.0 % of the essential oil total (GC/FID chromatogram were identified. The most abundant compounds were benzyl isothiocyanate (82.5 %, benzene acetonitrile (3.9 % and 2-phenylethyl isovalerate (2.9 %. Higher content in nitrogen- and sulfur-containing compounds accounting to 86.4 % of the volatile fraction composition of T. majus were quantified.

  6. High salinity volatile phases in magmatic Ni-Cu-platinum group element deposits

    Science.gov (United States)

    Hanley, J. J.; Mungall, J. E.

    2004-12-01

    The role of "deuteric" fluids (exsolved magmatic volatile phases) in the development of Ni-Cu-PGE (platinum group element) deposits in mafic-ultramafic igneous systems is poorly understood. Although considerable field evidence demonstrates unambiguously that fluids modified most large primary Ni-Cu-PGE concentrations, models which hypothesize that fluids alone were largely responsible for the economic concentration of the base and precious metals are not widely accepted. Determination of the trace element composition of magmatic volatile phases in such ore-forming systems can offer considerable insight into the origin of potentially mineralizing fluids in such igneous environments. Laser ablation ICP-MS microanalysis allows researchers to confirm the original metal budget of magmatic volatile phases and quantify the behavior of trace ore metals in the fluid phase in the absence of well-constrained theoretical or experimental predictions of ore metal solubility. In this study, we present new evidence from major deposits (Sudbury, Ontario, Canada; Stillwater Complex, Montana, U.S.A.) that compositionally distinct magmatic brines and halide melt phases were exsolved from crystallizing residual silicate melt and trapped within high-T fluid conduits now comprised of evolved rock compositions (albite-quartz graphic granite, orthoclase-quartz granophyre). Petrographic evidence demonstrates that brines and halide melts coexisted with immiscible carbonic phases at the time of entrapment (light aliphatic hydrocarbons, CO2). Brine and halide melt inclusions are rich in Na, Fe, Mn, K, Pb, Zn, Ba, Sr, Al and Cl, and homogenize by either halite dissolution at high T ( ˜450-700° C) or by melting of the salt phase (700-800° C). LA-ICPMS analyses of single inclusions demonstrate that high salinity volatile phases contained abundant base metals (Cu, Fe, Sn, Bi) and precious metals (Pt, Pd, Au, Ag) at the time of entrapment. Notably, precious metal concentrations in the inclusions

  7. Growth of fungi on volatile aromatic hydrocarbons: environmental technology perspectives

    NARCIS (Netherlands)

    Prenafeta Boldú, F.X.

    2002-01-01

    The present study aimed the better understanding of the catabolism of monoaromatic hydrocarbons by fungi. This knowledge can be used to enhance the biodegradation of BTEX pollutants. Fungi with the capacity of using toluene as the sole source of carbon and energy were isolated by enriching

  8. A high volume sampling system for isotope determination of volatile halocarbons and hydrocarbons

    Directory of Open Access Journals (Sweden)

    E. Bahlmann

    2011-10-01

    Full Text Available The isotopic composition of volatile organic compounds (VOCs can provide valuable information on their sources and fate not deducible from mixing ratios alone. In particular the reported carbon stable isotope ratios of chloromethane and bromomethane from different sources cover a δ13C-range of almost 100‰ making isotope ratios a very promising tool for studying the biogeochemistry of these compounds. So far, the determination of the isotopic composition of C1 and C2 halocarbons others than chloromethane is hampered by their low mixing ratios.

    In order to determine the carbon isotopic composition of C1 and C2 halocarbons with mixing ratios as low as 1 pptv (i a field suitable cryogenic high volume sampling system and (ii a chromatographic set up for processing these samples have been developed and validated. The sampling system was tested at two different sampling sites, an urban and a coastal location in Northern Germany. The average δ13C-values for bromomethane at the urban site were −42.9 ± 1.1‰ and agreed well with previously published results. But at the coastal site bromomethane was substantially enriched in 13C by almost 10‰. Less pronounced differences were observed for chlorodifluoromethane, 1,1,1-trichloroethane and chloromethane. We suggest that these differences are related to the turnover of these compounds in ocean surface waters. Furthermore we report first carbon isotope ratios for iodomethane (−40.4‰ to −79.8‰, bromoform (−13.8‰ to 22.9‰, and other halocarbons.

  9. Effect of Vertical Shoot-Positioned, Scott-Henry, Geneva Double-Curtain, Arch-Cane, and Parral Training Systems on the Volatile Composition of Albariño Wines

    Directory of Open Access Journals (Sweden)

    Mar Vilanova

    2017-09-01

    Full Text Available Viticultural practices influence both grape and wine quality. The influence of training systems on volatile composition was investigated for Albariño wine from Rías Baixas AOC in Northwest Spain. The odoriferous contribution of the compounds to the wine aroma was also studied. Volatile compounds belonging to ten groups (alcohols, C6-compounds, ethyl esters, acetates, terpenols, C13-norisoprenoids, volatile phenols, volatile fatty acids, lactones and carbonyl compounds were determined in Albariño wines from different training systems, Vertical Shoot-Positioned (VSP, Scott-Henry (SH, Geneva Double-Curtain (GDC, Arch-Cane (AC, and Parral (P during 2010 and 2011 vintages. Wines from GDC showed the highest total volatile composition with the highest concentrations of alcohols, ethyl esters, fatty acids, and lactones families. However, the highest levels of terpenes and C13-norisoprenoids were quantified in the SH system. A fruitier aroma was observed in Albariño wines from GDC when odor activity values were calculated.

  10. Variations in Volatile Oil Yield and Composition of "Xin-yi" (Magnolia biondii Pamp. Flower Buds) at Different Growth Stages.

    Science.gov (United States)

    Hu, Mingli; Bai, Mei; Ye, Wei; Wang, Yaling; Wu, Hong

    2018-06-01

    Dried flower buds of Magnolia biondii Pamp. are the main ingredient in "Xin-yi" in China, and the volatile oils of M. biondii flower buds are the principal medicinal component. Gas chromatographymass spectrometry (GC-MS) and microscopic techniques were employed to detect the volatile yields of M. biondii flowers at various growth stages. The volatile oil yields of M. biondii flowers differed significantly at different growth stages and were closely related to flower dry weight, oil cell density and degree of oil accumulation. In February 2016, flower buds had the highest dry weight, the maximum percentage of oil cells at the oil saturation stage and the highest density of oil cells, which coincided with the highest oil yield. In March 2016, flower buds had a lower dry weight, a higher percentage of oil cells at the oil-degrading stage and the lowest oil cell density, resulting in decreased oil yields. The total amounts of the major medicinal components in the M. biondii flower also showed regular changes at different growth stages. In January and February of 2016, M. biondii flowers had a higher dry weight, volatile oil yield and total content of medicinal ingredients, which was the best time for harvesting high-quality medicinal components. Our study reveals that volatile oil content and chemical composition are closely related to the growth stage of M. biondii flower buds. The results provide a scientific morphology and composition index for evaluating the medicinal value and harvesting of high-quality M. biondii medicinal herbs.

  11. The pollution characteristics of odor, volatile organochlorinated compounds and polycyclic aromatic hydrocarbons emitted from plastic waste recycling plants.

    Science.gov (United States)

    Tsai, Chung-Jung; Chen, Mei-Lien; Chang, Keng-Fu; Chang, Fu-Kuei; Mao, I-Fang

    2009-02-01

    Plastic waste treatment trends toward recycling in many countries; however, the melting process in the facilities which adopt material recycling method for treating plastic waste may emit toxicants and cause sensory annoyance. The objectives of this study were to analyze the pollution characteristics of the emissions from the plastic waste recycling plants, particularly in harmful volatile organochlorinated compounds, polycyclic aromatic hydrocarbons (PAHs), odor levels and critical odorants. Ten large recycling plants were selected for analysis of odor concentration (OC), volatile organic compounds (VOCs) and PAHs inside and outside the plants using olfactometry, gas chromatography-mass spectrometry and high performance liquid chromatography-fluorescence detector, respectively. The olfactometric results showed that the melting processes used for treating polyethylene/polypropylene (PE/PP) and polyvinyl chloride (PVC) plastic waste significantly produced malodor, and the odor levels at downwind boundaries were 100-229 OC, which all exceeded Taiwan's EPA standard of 50 OC. Toluene, ethylbenzene, 4-methyl-2-pentanone, methyl methacrylate and acrolein accounted for most odors compared to numerous VOCs. Sixteen organochlorinated compounds were measured in the ambient air emitted from the PVC plastic waste recycling plant and total concentrations were 245-553 microg m(-3); most were vinyl chloride, chloroform and trichloroethylene. Concentrations of PAHs inside the PE/PP plant were 8.97-252.16 ng m(-3), in which the maximum level were 20-fold higher than the levels detected from boundaries. Most of these recycling plants simply used filter to treat the melting fumes, and this could not efficiently eliminate the gaseous compounds and malodor. Improved exhaust air pollution control were strongly recommended in these industries.

  12. Release of volatile and semi-volatile toxicants during house fires.

    Science.gov (United States)

    Hewitt, Fiona; Christou, Antonis; Dickens, Kathryn; Walker, Richard; Stec, Anna A

    2017-04-01

    Qualitative results are presented from analysis of volatile and semi-volatile organic compounds (VOCs/SVOCs) obtained through sampling of gaseous effluent and condensed particulates during a series of experimental house fires conducted in a real house. Particular emphasis is given to the 16 polycyclic aromatic hydrocarbons (PAHs) listed by the Environmental Protection Agency due to their potentially carcinogenic effects. The initial fuel packages were either cooking oil or a single sofa; these were burned both alone, and in furnished surroundings. Experiments were performed at different ventilation conditions. Qualitative Gas Chromatography-Mass Spectrometry (GC-MS) analysis found VOC/SVOC releases in the developing stages of the fires, and benzo(a)pyrene - the most carcinogenic PAH - was found in at least one sampling interval in the majority of fires. A number of phosphorus fire retardants were detected, in both the gaseous effluent and particulates, from fires where the initial fuel source was a sofa. Their release during the fire is significant as they pose toxicological concerns separate from those presented by the PAHs. Copyright © 2016. Published by Elsevier Ltd.

  13. Seasonal Variation in the Chemical Composition and Antimicrobial Activity of Volatile Oils of Three Species of Leptospermum (Myrtaceae Grown in Brazil

    Directory of Open Access Journals (Sweden)

    Antonio Lelis Pinheiro

    2011-01-01

    Full Text Available This study investigates the seasonal variation of three species of Leptospermum (Myrtaceae grown in Brazil. The chemical composition of the volatile oils of L. flavescens and L. petersonii did not show any significant seasonal variation in the major components, while for Leptospermum madidum subsp. sativum the levels of major constituents of the volatile oils varied with the harvest season. Major fluctuations in the composition of L. madidum subsp. sativum oil included α-pinene (0–15.2%, β-pinene (0.3–18.5%, α-humulene (0.8–30%, 1,8-cineole (0.4–7.1% and E-caryophyllene (0.4–11.9%. Levels of β-pinene (0.3–5.6%, terpinen-4-ol (4.7–7.2% and nerolidol (55.1–67.6% fluctuated seasonally in the L. flavescens oil. In L. petersonii, changes were noted for geranial (29.8–32.8%, citronellal (26.5–33.9% and neral (22.7–23.5%. The activity of the volatile oils against the tested bacteria differed, depending on season the oils were obtained. In general, the volatile oils were more active against Gram-positive bacteria.

  14. Volatile composition and enantioselective analysis of chiral terpenoids of nine fruit and vegetable fibres resulting from juice industry by-products

    OpenAIRE

    Marsol i Vall, Alexis; Sgorbini, Barbara; Cagliero, Cecilia; Bicchi, Carlo; Eras i Joli, Jordi; Balcells Fluvià, Mercè

    2017-01-01

    Fruit and vegetable fibres resulting as by-products of the fruit juice industry have won popularity because they can be valorised as food ingredients. In this regard, bioactive compounds have already been studied but little attention has been paid to their remaining volatiles. Considering all the samples, 57 volatiles were identified. Composition greatly differed between citrus and noncitrus fibres. The former presented over 90% of terpenoids, with limonene being the most abundant and ranging...

  15. Webinar Presentation: Exposures to Polycyclic Aromatic Hydrocarbons and Childhood Growth Trajectories and Body Composition: Linkages to Disrupted Self-Regulatory Processes

    Science.gov (United States)

    This presentation, Exposures to Polycyclic Aromatic Hydrocarbons and Childhood Growth Trajectories and Body Composition: Linkages to Disrupted Self-Regulatory Processes, was given at the NIEHS/EPA Children's Centers 2016 Webinar Series: Childhood Obesity

  16. Aerosol volatility in a boreal forest environment

    Science.gov (United States)

    Häkkinen, S. A. K.; ńijälä, M.; Lehtipalo, K.; Junninen, H.; Virkkula, A.; Worsnop, D. R.; Kulmala, M.; Petäjä, T.; Riipinen, I.

    2012-04-01

    Climate and health effects of atmospheric aerosols are determined by their properties such as their chemical composition. Aerosol chemical composition can be studied indirectly by measuring volatility of aerosol particles. The volatility of submicron aerosol particles (20-500 nm) was studied in a boreal forest site at SMEAR II (Station for Measuring Ecosystem-Atmosphere Relations II) station (Vesala et al., 1998) in Hyytiälä, Finland, during 01/2008-05/2010. The instrument used for the measurements was VDMPS (Volatility Differential Mobility Particle Sizer), which consists of two separate instruments: DMPS (Differential Mobility Particle Sizer, Aalto et al., 2001) and TD (Thermodenuder, Wehner et al., 2002). Aerosol evaporation was examined by heating the aerosol and comparing the total aerosol mass before and after heating. In the VDMPS system ambient aerosol sample was heated up to temperatures ranging from 80 °C to 280 °C. The higher the heating temperature was the more aerosol material was evaporated. There was a non-volatile residual present in aerosol particles when heated up to 280 °C. This residual explained (20±8)% of the total aerosol mass. Aerosol non-volatile mass fraction was highest during winter and smallest during summer months. The role of black carbon in the observed non-volatile residual was determined. Black carbon explained 40 to 90% of the non-volatile mass. Especially during colder seasons noticeable amount of non-volatile material, something else than black carbon, was observed. According to Kalberer et al. (2004) some atmospheric organic species can form polymers that have high evaporation temperatures. Also low-volatile organic salts may contribute to the non-volatile aerosol (Smith et al., 2010). Aerosol mass composition measured directly with AMS (Aerosol Mass Spectrometer, Jayne et al., 2000) was analyzed in order to examine the properties of the non-volatile material (other than black carbon). The AMS measurements were performed

  17. Influence of choice of yeasts on volatile fermentation-derived compounds, colour and phenolics composition in Cabernet Sauvignon wine.

    Science.gov (United States)

    Blazquez Rojas, Inmaculada; Smith, Paul A; Bartowsky, Eveline J

    2012-12-01

    Wine colour, phenolics and volatile fermentation-derived composition are the quintessential elements of a red wine. Many viticultural and winemaking factors contribute to wine aroma and colour with choice of yeast strain being a crucial factor. Besides the traditional Saccharomyces species S. cerevisiae, S. bayanus and several Saccharomyces interspecific hybrids are able to ferment grape juice to completion. This study examined the diversity in chemical composition, including phenolics and fermentation-derived volatile compounds, of an Australian Cabernet Sauvignon due to the use of different Saccharomyces strains. Eleven commercially available Saccharomyces strains were used in this study; S. cerevisiae (7), S. bayanus (2) and interspecific Saccharomyces hybrids (2). The eleven Cabernet Sauvignon wines varied greatly in their chemical composition. Nine yeast strains completed alcoholic fermentation in 19 days; S. bayanus AWRI 1375 in 26 days, and S. cerevisiae AWRI 1554 required 32 days. Ethanol concentrations varied in the final wines (12.7-14.2 %). The two S. bayanus strains produced the most distinct wines, with the ability to metabolise malic acid, generate high glycerol concentrations and distinctive phenolic composition. Saccharomyces hybrid AWRI 1501 and S. cerevisiae AWRI 1554 and AWRI 1493 also generated distinctive wines. This work demonstrates that the style of a Cabernet Sauvignon can be clearly modulated by choice of commercially available wine yeast.

  18. The role of mass spectrometry in hydrocarbon analysis

    International Nuclear Information System (INIS)

    Kerenyi, E.

    1980-01-01

    Modern mass spectrometry has an outstandin.o role in solving problems concerning the composition and structure of hydrocarbon mixtures and their derivatives, petroleum and petrochemical products. Its efficiency in hydrocarbon analysis has been increased not only by high resolving power and computerized spectrum processing but also by the metastable ion spectrum technique promoting structural examinations, by mild ionization facilitating composition analysis, and by selective ion-detecting technique. The author presents the advantages of the metastable ion spectra, the field ionization, field desorption and other mild ionization methods, and finally, those of fragmentation analysis in connection with the examination of hydrocarbons and hydrocarbon derivatives. Examples taken from the literature and from the research work carried out in the Institute are also given. (author)

  19. Expectations for Particulate Contamination Relevant to in Situ Atmospheric Sampling for Compositional Analysis at Uranus

    Science.gov (United States)

    Wong, M. H.

    2017-12-01

    NASA and ESA are considering options for in situ science with atmospheric entry probes to the ice giants Uranus and Neptune. Nominal probe entry mass is in the 300-kg range, although a miniaturized secondary probe option is being studied in the 30-kg range. In all cases, compositional sampling would commence near the 100-mbar level at Uranus, after ejection of the heat shield and deployment of the descent parachute. In this presentation, I review existing literature on the composition, mass loading, and vertical distribution of condensed material that the probe may encounter. Sample inlets for measurement of the gas composition should be heated to avoid potential buildup of condensate, which would block the flow of atmospheric gas into composition sensors. Heating rate and temperature values -- sufficient to keep sample inlets clean under various assumptions -- will be presented. Three main types of condensed material will be considered: Stratospheric hydrocarbon ices: Solar UV photolyzes CH4, leading to the production of volatile hydrocarbons with higher C/H ratios. These species diffuse from their production regions into colder levels where the ices of C2H2, C2H6, and C4H2 condense. Some studies have also considered condensation of C3H8, C4H10, C6H6, and C6H2. Gunk: The hydrocarbon ices are thought to become polymerized due to irradiation from solar UV. The exact composition of the resulting gunk is not known. Solid-state photochemical processing may produce the traces of reddish (blue-absorbing) haze material, present in the troposphere at temperatures warm enough to sublimate the simple hydrocarbon ices. Tropospheric ices: In the region accessible to probes under study (P < 10 bar), much thicker condensation clouds may form from volatile gases CH4, NH3, and H2S. If large amounts of NH3 are sequestered in the deeper H2O liquid cloud, then the S/N ratio could exceed 1 in the probe-accessible region of the atmosphere, leading to NH4SH and H2S ices below the CH4

  20. Composition of sulla (Hedysarum coronarium L.) honey solvent extractives determined by GC/MS: norisoprenoids and other volatile organic compounds.

    Science.gov (United States)

    Jerković, Igor; Tuberoso, Carlo I G; Tuberso, Carlo I G; Gugić, Mirko; Bubalo, Dragan

    2010-09-09

    Samples of unifloral sulla (Hedysarum coronarum L.) honey from Sardinia (Italy) were analysed. To investigate the chemical composition of the honey volatiles two solvent systems were used for ultrasonic solvent extraction (USE): 1) a 1:2 (v/v) pentane and diethyl ether mixture and 2) dichloromethane. All the extracts were analysed by GC and GC/MS. These procedures have permitted the identification of 56 compounds that include norisoprenoids, benzene derivatives, aliphatic compounds and Maillard reaction products. Norisoprenoids were the major compounds in both extracts, dominated by vomifoliol (5.3-11.2%; 9.6-14.0%) followed by minor percentages of other norisoprenoids such as α-isophorone, 4-ketoisophorone, 3-oxo-α-ionol or 3-oxo-α-ionone. Other abundant single compounds in the extracts were 3-hydroxy-4-phenylbutan-2-one (0.8-5.4%; 0.6-5.7%) and methyl syringate (3.0-5.7%; 2.2-4.1%). The composition of the volatiles and semi-volatiles in the obtained extracts suggests that sulla honey is quite distinctive relative to the other honeys that have been chemically studied by GC/MS, but no specific markers of the honey botanical origin were found.

  1. Composition of Sulla (Hedysarum coronarium L. Honey Solvent Extractives Determined by GC/MS: Norisoprenoids and Other Volatile Organic Compounds

    Directory of Open Access Journals (Sweden)

    Dragan Bubalo

    2010-09-01

    Full Text Available Samples of unifloral sulla (Hedysarum coronarum L. honey from Sardinia (Italy were analysed. To investigate the chemical composition of the honey volatiles two solvent systems were used for ultrasonic solvent extraction (USE: 1 a 1:2 (v/v pentane and diethyl ether mixture and 2 dichloromethane. All the extracts were analysed by GC and GC/MS. These procedures have permitted the identification of 56 compounds that include norisoprenoids, benzene derivatives, aliphatic compounds and Maillard reaction products. Norisoprenoids were the major compounds in both extracts, dominated by vomifoliol (5.3-11.2%; 9.6-14.0% followed by minor percentages of other norisoprenoids such as α-isophorone, 4-ketoisophorone, 3-oxo-α-ionol or 3-oxo-α-ionone. Other abundant single compounds in the extracts were 3-hydroxy-4-phenylbutan-2-one (0.8-5.4%; 0.6-5.7% and methyl syringate (3.0-5.7%; 2.2-4.1%. The composition of the volatiles and semi-volatiles in the obtained extracts suggests that sulla honey is quite distinctive relative to the other honeys that have been chemically studied by GC/MS, but no specific markers of the honey botanical origin were found.

  2. Study utilization of extractable petroleum hydrocarbons biodegradation waste as the main material for making solid fuels

    Science.gov (United States)

    Hendrianie, Nuniek; Juliastuti, Sri Rachmania; Ar-rosyidah, Fanny Husna; Rochman, Hilal Abdur

    2017-05-01

    Nowadays the existence of energy sources of oil and was limited. Therefore, it was important to searching for new innovations of renewable energy sources by utilizing the waste into a source of energy. On the other hand, the process of extractable petroleum hydrocarbons biodegradation generated sludge that had calorific value and untapped. Because of the need for alternative sources of energy innovation with the concept of zero waste and the fuel potential from extractable petroleum hydrocarbons biodegradation waste, so it was necessary to study the use of extractable petroleum hydrocarbons biodegradation waste as the main material for making solid fuel. In addition, sawdust is a waste that had a great quantities and also had a high calorific value to be mixed with extractable petroleum hydrocarbons biodegradation waste. The purpose of this study was to determine the characteristics of the extractable petroleum hydrocarbons biodegradation waste and to determine the potential and a combination of a mixture of extractable petroleum hydrocarbons biodegradation waste and sawdust which has the best calorific value. The variables of this study was the composition of the waste and sawdust as follows 1:1; 1:3; and 3:1 (mass of sawdust : mass of waste) and time of sawdust carbonization was 10, 15 and 20 minutes. Sawdust was carbonized to get the high heating value. The characteristic of main material and fuel analysis performed with proximate analysis. While the calorific value analysis was performed with a bomb calorimeter. From the research, it was known that extractable petroleum hydrocarbons biodegradation waste had a moisture content of 3.06%; volatile matter 19.98%; ash content of 0.56%; fixed carbon content of 76.4% and a calorific value of 717 cal/gram. And a mixture that had the highest calorific value (4286.5 cal/gram) achieved in comparison sawdust : waste (3:1) by carbonization of sawdust for 20 minutes.

  3. Characterisation of volatile profiles in 50 native Peruvian chili pepper using solid phase microextraction-gas chromatography mass spectrometry (SPME-GCMS).

    Science.gov (United States)

    Patel, Kirti; Ruiz, Candy; Calderon, Rosa; Marcelo, Mavel; Rojas, Rosario

    2016-11-01

    The volatiles were characterised by headspace solid phase micro extraction (HS-SPME), gas chromatography mass spectrometry (GC-FID/MS). A total of 127 compounds were identified with terpenes (including mono terpenes and sesquiterpenes - a total of 45 compounds), esters (31 compounds) and hydrocarbons (20 compounds) were the predominant volatile compounds. Principal component analysis (PCA) of the volatile compounds yielded 2 significant PC's, which together accounted for 90.3% of the total variance in the data set and the scatter plot generated between PC1 and PC2 successfully segregated the 50 chili pepper samples into 7 groups. Clusters of hydrocarbons, esters, terpenes, aldehyde and ketones formed the major determinants of the difference. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Scanning probe microscopy for the analysis of composite Ti/hydrocarbon plasma polymer thin films

    Science.gov (United States)

    Choukourov, A.; Grinevich, A.; Slavinska, D.; Biederman, H.; Saito, N.; Takai, O.

    2008-03-01

    Composite Ti/hydrocarbon plasma polymer films with different Ti concentration were deposited on silicon by dc magnetron sputtering of titanium in an atmosphere of argon and hexane. As measured by Kelvin force microscopy and visco-elastic atomic force microscopy, respectively, surface potential and hardness increase with increasing Ti content. Adhesion force to silicon and to fibrinogen molecules was stronger for the Ti-rich films as evaluated from the AFM force-distance curves. Fibrinogen forms a very soft layer on these composites with part of the protein molecules embedded in the outermost region of the plasma polymer. An increase of the surface charge due to fibrinogen adsorption has been observed and attributed to positively charged αC domains of fibrinogen molecule.

  5. Effects of high pressure processing on fatty acid composition and volatile compounds in Korean native black goat meat.

    Science.gov (United States)

    Kang, Geunho; Cho, Soohyun; Seong, Pilnam; Park, Beomyoung; Kim, Sangwoo; Kim, Donghun; Kim, Youngjun; Kang, Sunmun; Park, Kyoungmi

    2013-08-01

    This study investigated the effects of high pressure processing (HPP) on fatty acid composition and volatile compounds in Korean native black goat (KNBG) meat. Fatty acid content in KNBG meat was not significantly (p > 0.05) different among the control goats and those subjected HPP. The 9,12-octadecadienoic acid and octadecanoic acid, well-known causes of off-flavors, were detected from meat of some KNBG. A difference between the control and HPP treatment was observed in the discriminated function analysis using an electronic nose. The results suggest that the volatile compounds in KNBG meat were affected by HPP.

  6. Trichomes and chemical composition of the volatile oil of Trichogonia cinerea (Gardner R. M. King & H. Rob. (Eupatorieae, Asteraceae

    Directory of Open Access Journals (Sweden)

    YANNE S. FERNANDES

    2016-03-01

    Full Text Available Trichogonia cinerea is endemic to Brazil and occurs in areas of cerrado and campo rupestre. In this study, we characterized the glandular and non-glandular trichomes on the aerial parts of this species, determined the principal events in the development of the former, and identified the main constituents of the volatile oil produced in its aerial organs. Fully expanded leaves, internodes, florets, involucral bracts, and stem apices were used for the characterization of trichomes. Leaves, internodes, florets, and involucral bracts were examined by light microscopy and scanning electron microscopy, whereas stem apices were examined only by light microscopy. Branches in the reproductive phase were used for the extraction and determination of the composition of the volatile oil. The species has three types of glandular trichomes, biseriate vesicular, biseriate pedunculate, and multicellular uniseriate, which secrete volatile oils and phenolic compounds. The major components identified in the volatile oil were 3,5-muuroladiene (39.56% and butylated hydroxytoluene (13.07%.

  7. Trichomes and chemical composition of the volatile oil of Trichogonia cinerea (Gardner) R. M. King & H. Rob. (Eupatorieae, Asteraceae).

    Science.gov (United States)

    Fernandes, Yanne S; Trindade, Luma M P; Rezende, Maria Helena; Paula, José R; Gonçalves, Letícia A

    2016-03-01

    Trichogonia cinerea is endemic to Brazil and occurs in areas of cerrado and campo rupestre. In this study, we characterized the glandular and non-glandular trichomes on the aerial parts of this species, determined the principal events in the development of the former, and identified the main constituents of the volatile oil produced in its aerial organs. Fully expanded leaves, internodes, florets, involucral bracts, and stem apices were used for the characterization of trichomes. Leaves, internodes, florets, and involucral bracts were examined by light microscopy and scanning electron microscopy, whereas stem apices were examined only by light microscopy. Branches in the reproductive phase were used for the extraction and determination of the composition of the volatile oil. The species has three types of glandular trichomes, biseriate vesicular, biseriate pedunculate, and multicellular uniseriate, which secrete volatile oils and phenolic compounds. The major components identified in the volatile oil were 3,5-muuroladiene (39.56%) and butylated hydroxytoluene (13.07%).

  8. Legacy effects of anaerobic soil disinfestation on soil bacterial community composition and production of pathogen-suppressing volatiles

    Directory of Open Access Journals (Sweden)

    Maaike evan Agtmaal

    2015-07-01

    Full Text Available There is increasing evidence that microbial volatiles (VOCs play an important role in natural suppression of soil-borne diseases, but little is known on the factors that influence production of suppressing VOCs. In the current study we examined whether a stress-induced change in soil microbial community composition would affect the production by soils of VOCs suppressing the plant-pathogenic oomycete Pythium. Using pyrosequencing of 16S ribosomal gene fragments we compared the composition of bacterial communities in sandy soils that had been exposed to anaerobic disinfestation (AD, a treatment used to kill harmful soil organisms, with the composition in untreated soils. Three months after the AD treatment had been finished, there was still a clear legacy effect of the former anaerobic stress on bacterial community composition with a strong increase in relative abundance of the phylum Bacteroidetes and a significant decrease of the phyla Acidobacteria, Planctomycetes, Nitrospirae, Chloroflexi and Chlorobi. This change in bacterial community composition coincided with loss of production of Pythium suppressing soil volatiles (VOCs and of suppression of Pythium impacts on Hyacinth root development. One year later, the composition of the bacterial community in the AD soils was reflecting that of the untreated soils. In addition, both production of Pythium-suppressing VOCs and suppression of Pythium in Hyacinth bioassays had returned to the levels of the untreated soil. GC/MS analysis identified several VOCs, among which compounds known to be antifungal, that were produced in the untreated soils but not in the AD soils. These compounds were again produced 15 months after the AD treatment. Our data indicate that soils exposed to a drastic stress can temporarily lose pathogen suppressive characteristics and that both loss and return of these suppressive characteristics coincides with shifts in the soil bacterial community composition. Our data are

  9. Volatility measurement of atmospheric submicron aerosols in an urban atmosphere in southern China

    Science.gov (United States)

    Cao, Li-Ming; Huang, Xiao-Feng; Li, Yuan-Yuan; Hu, Min; He, Ling-Yan

    2018-02-01

    Aerosol pollution has been a very serious environmental problem in China for many years. The volatility of aerosols can affect the distribution of compounds in the gas and aerosol phases, the atmospheric fates of the corresponding components, and the measurement of the concentration of aerosols. Compared to the characterization of chemical composition, few studies have focused on the volatility of aerosols in China. In this study, a thermodenuder aerosol mass spectrometer (TD-AMS) system was deployed to study the volatility of non-refractory submicron particulate matter (PM1) species during winter in Shenzhen. To our knowledge, this paper is the first report of the volatilities of aerosol chemical components based on a TD-AMS system in China. The average PM1 mass concentration during the experiment was 42.7±20.1 µg m-3, with organic aerosol (OA) being the most abundant component (43.2 % of the total mass). The volatility of chemical species measured by the AMS varied, with nitrate showing the highest volatility, with a mass fraction remaining (MFR) of 0.57 at 50 °C. Organics showed semi-volatile characteristics (the MFR was 0.88 at 50 °C), and the volatility had a relatively linear correlation with the TD temperature (from the ambient temperature to 200 °C), with an evaporation rate of 0.45 % °C-1. Five subtypes of OA were resolved from total OA using positive matrix factorization (PMF) for data obtained under both ambient temperature and high temperatures through the TD, including a hydrocarbon-like OA (HOA, accounting for 13.5 %), a cooking OA (COA, 20.6 %), a biomass-burning OA (BBOA, 8.9 %), and two oxygenated OAs (OOAs): a less-oxidized OOA (LO-OOA, 39.1 %) and a more-oxidized OOA (MO-OOA, 17.9 %). Different OA factors presented different volatilities, and the volatility sequence of the OA factors at 50 °C was HOA (MFR of 0.56) > LO-OOA (0.70) > COA (0.85) ≈ BBOA (0.87) > MO-OOA (0.99), which was not completely consistent with the sequence of their O

  10. Comparison of the environmental impacts of two remediation technologies used at hydrocarbon contaminated sites

    International Nuclear Information System (INIS)

    Viikala, R.; Kuusola, J.

    2000-01-01

    Investigation and remediation of contaminated sites has rapidly increased in Finland during the last decade. Public organisations as well as private companies are investigating and remediating their properties, e.g. redevelopment or business transactions. Also numerous active and closed gasoline stations have been investigated and remediated during the last few years. Usually the contaminated sites are remediated to limit values regardless of the risk caused by contamination. The limit values currently used in Finland for hydrocarbon remediation at residential or ground water areas are 300 mg/kg of total hydrocarbons and 100 mg/kg of volatile hydrocarbons (boiling point < appr. 200 deg C). Additionally, compounds such as aromatic hydrocarbons have specific limit values. Remediation of hydrocarbon contaminated sites is most often carried out by excavating the contaminated soil and taking it to a landfill by lorries. As distances from the sites to landfills are generally rather long, from tens of kilometres to few hundred kilometres, it is evident that this type of remediation has environmental impacts. Another popular technology used at sites contaminated by volatile hydrocarbons is soil vapour extraction (SVE). SVE is a technique of inducing air flow through unsaturated soils by vapour extraction wells or pipes to remove organic contaminants with an off-gas treatment system. The purpose of this study was to evaluate some of the environmental impacts caused by remediation of hydrocarbon contaminated soil. Energy consumption and air emissions related remedial activities of the two methods were examined in this study. Remediation of the sites used in this study were carried out by Golder Associates Oy in different parts of Finland in different seasons. Evaluation was made by using life cycle assessment based approach

  11. Emission of climate relevant volatile organochlorines by plants occurring in temperate forests

    Czech Academy of Sciences Publication Activity Database

    Forczek, Sándor; Laturnus, F.; Doležalová, Jana; Holík, Josef; Wimmer, Zdeněk

    2015-01-01

    Roč. 61, č. 3 (2015), s. 103-108 ISSN 1214-1178 R&D Projects: GA ČR GA13-11101S Institutional support: RVO:61389030 Keywords : volatile chlorinated hydrocarbons * biodegradation * Sphagnum moss Subject RIV: EF - Botanics Impact factor: 1.039, year: 2015

  12. Aspects of petroleum hydrocarbon metabolism in marine animals

    Science.gov (United States)

    Mironov, O. G.

    1980-03-01

    Studies on hydrocarbon composition of Black Sea mussels Mytilus galloprovincialis sampled from different habitats indicate that the quantity and composition of hydrocarbons distributed in the molluscs depend on season and sea-water quality. The data obtained under experimental conditions testify to the possibility of hydrocarbon concentration in mussel tissues after death. During filtration in sea water containing oil and oil products, these pollutants are bound into faeces and pseudofaeces which contain a greater percentage of aromatic compounds than the oil initially present in sea water. Quantitative data are presented on hydrocarbon changes in mussel excretory products during transfer from oil-polluted to clean sea water. When Black Sea crabs Eriphia verrucosa are fed with mussels containing fuel-oil components accumulated from sea water, the pollutants concentrate in the whole body of the crab. This is in contrast to parenteral oil uptake, which leads to a concentration of most of the hydrocarbon in the muscles.

  13. Investigation of non-volatile additives on the process of distillation of hydrocarbon mixtures

    Directory of Open Access Journals (Sweden)

    М.Б. Степанов

    2009-02-01

    Full Text Available  The given results of researches of influence of nonvolatile additives on processes of distillation of individual hydrocarbons and their mixes, including petroleum and mineral oil. With the help of the developed computer system of the continuous control of distillation it is shown, that at the presence of small amounts of the additive decrease of temperature of the beginning of boiling of hydrocarbons is observed, their speeds of banish and exits of light fuel mineral oil grow during initial oil refining

  14. Phytotoxic Activity and Chemical Composition of Aqueous Volatile Fractions from Eucalyptus Species

    Science.gov (United States)

    Zhang, Jinbiao; An, Min; Wu, Hanwen; Liu, De Li; Stanton, Rex

    2014-01-01

    The essential oils from four Eucalyptus species (E. spathulata, E. salubris, E. brockwayii and E. dundasii) have been previously confirmed to have stronger inhibitory effects on germination and seedling growth of silverleaf nightshade (Solanum elaeagnifolium Cav.). The aqueous volatile fractions (AVFs) were the water soluble volatile fractions produced together with the essential oils (water insoluble fractions) during the steam distillation process. The aim of this study was to further assess the phytotoxicity of AVFs from the four Eucalyptus species and their chemical composition. The fresh leaves of the four Eucalyptus species were used for the extraction of AVFs. The AVFs were tested for their phytotoxic effects on the perennial weed, silverleaf nightshade under laboratory conditions. The chemical compositions of the AVFs were determined by gas chromatograph–mass spectrometry (GC-MS). Our results showed that the AVFs had strong inhibition on the germination and seedling growth of silverleaf nightshade. The inhibition index increased with the increasing concentrations of AVFs. The inhibitory effects of the AVFs varied between different Eucalyptus species. The AVF from E. salubris demonstrated the highest inhibitory activity on the weed tested, with complete inhibition on germination and seedling growth at a concentration of 75%. The GC-MS analysis revealed that 1,8-cineole, isopentyl isovalerate, isomenthol, pinocarvone, trans-pinocarveol, alpha-terpineol and globulol were the main compounds in the AVFs. These results indicated that all AVFs tested had differential inhibition on the germination and seedling growth of silverleaf nightshade, which could be due to the joint effects of compounds present in the AVFs as these compounds were present in different quantities and ratio between Eucalyptus species. PMID:24681490

  15. Phytotoxic activity and chemical composition of aqueous volatile fractions from Eucalyptus species.

    Directory of Open Access Journals (Sweden)

    Jinbiao Zhang

    Full Text Available The essential oils from four Eucalyptus species (E. spathulata, E. salubris, E. brockwayii and E. dundasii have been previously confirmed to have stronger inhibitory effects on germination and seedling growth of silverleaf nightshade (Solanum elaeagnifolium Cav.. The aqueous volatile fractions (AVFs were the water soluble volatile fractions produced together with the essential oils (water insoluble fractions during the steam distillation process. The aim of this study was to further assess the phytotoxicity of AVFs from the four Eucalyptus species and their chemical composition. The fresh leaves of the four Eucalyptus species were used for the extraction of AVFs. The AVFs were tested for their phytotoxic effects on the perennial weed, silverleaf nightshade under laboratory conditions. The chemical compositions of the AVFs were determined by gas chromatograph-mass spectrometry (GC-MS. Our results showed that the AVFs had strong inhibition on the germination and seedling growth of silverleaf nightshade. The inhibition index increased with the increasing concentrations of AVFs. The inhibitory effects of the AVFs varied between different Eucalyptus species. The AVF from E. salubris demonstrated the highest inhibitory activity on the weed tested, with complete inhibition on germination and seedling growth at a concentration of 75%. The GC-MS analysis revealed that 1,8-cineole, isopentyl isovalerate, isomenthol, pinocarvone, trans-pinocarveol, alpha-terpineol and globulol were the main compounds in the AVFs. These results indicated that all AVFs tested had differential inhibition on the germination and seedling growth of silverleaf nightshade, which could be due to the joint effects of compounds present in the AVFs as these compounds were present in different quantities and ratio between Eucalyptus species.

  16. Alkanes as Components of Soil Hydrocarbon Status: Behavior and Indication Significance

    Science.gov (United States)

    Gennadiev, A. N.; Zavgorodnyaya, Yu. A.; Pikovskii, Yu. I.; Smirnova, M. A.

    2018-01-01

    Studies of soils on three key plots with different climatic conditions and technogenic impacts in Volgograd, Moscow, and Arkhangelsk oblasts have showed that alkanes in the soil exchange complex have some indication potential for the identification of soil processes. The following combinations of soil-forming factors and processes have been studied: (a) self-purification of soil after oil pollution; (b) accumulation of hydrocarbons coming from the atmosphere to soils of different land use patterns; and (c) changes in the soil hydrocarbon complex beyond the zone of technogenic impact due to the input of free hydrocarbon-containing gases. At the injection input of hydrocarbon pollutants, changes in the composition and proportions of alkanes allow tracing the degradation trend of pollutants in the soil from their initial content to the final stage of soil self-purification, when the background concentrations of hydrocarbons are reached. Upon atmospheric deposition of hydrocarbons onto the soil, from the composition and mass distribution of alkanes, conclusions can be drawn about the effect of toxicants on biogeochemical processes in the soil, including their manifestation under different land uses. Composition analysis of soil alkanes in natural landscapes can reveal signs of hydrocarbon emanation fluxes in soils. The indication potentials of alkanes in combination with polycyclic aromatic hydrocarbons and other components of soil hydrocarbon complex can also be used for the solution of other soil-geochemical problems.

  17. Volatiles in the Martian regolith

    International Nuclear Information System (INIS)

    Clark, B.C.; Baird, A.K.

    1979-01-01

    An inventory of released volatiles on Mars has been derived based upon Viking measurements of atmospheric and surface chemical composition, and upon the inferred mineralogy of a ubiquitous regolith, assumed to average 200m in depth. This model is consistent with the relative abundances of volatiles (except for S) on the Earth's surface, but implies one-fifteenth of the volatile release of Earth if starting materials were comparable. All constituents are accommodated as chemical components of, or absorbed phases on, regolith materials--without the necessity of invoking unobservable deposits of carbonates, nitrates, or permafrost ice

  18. Emissions of volatile hydrocarbons (VOC) during drying of sawdust; Utslaepp av laettflyktiga kolvaeten vid torkning av biobraenslen

    Energy Technology Data Exchange (ETDEWEB)

    Granstroem, Karin

    2001-08-01

    In the project 'Emissions of volatile hydrocarbons (VOC) during drying of sawdust' the identity, amount and composition of monoterpenes found in the drying medium of a fluidized bed drier drying sawdust from Norwegian spruce and Scotch pine has been determined. The energy efficiency of the drier has also been measured. The aim of this project was to reduce both emissions and energy required for drying, to minimize environmental and health hazards, and make drying more competitive. This would help our primary target group - small scale saw mills - to make use of the sawdust produced as a by- product by making pellets and briquettes. If the VOC remains in the sawdust its energy content will improve and therefore also its value as a fuel. The sawdust was dried to different moisture levels in a spouted bed drier at atmospheric pressure, using either recirculating or not recirculating drying medium with temperatures 140, 170 or 200 deg C. The emissions of VOC were measured using a flame ionization detector (FID) and the nature of the emissions analyzed with a gas chromatograph with mass spectrometric detector (GC-MS). The GC-MS data is reported as emitted substance per oven dry weight (odw). Experiments show that terpenes do not leave the sawdust in great amounts until it is dried to a moisture content (water/total weight) below 10%. When sawdust is dried to a predetermined moisture level, the terpene emissions increase when warmer incoming drying medium is used. The monoterpenes found in greatest amount are a-pinene, b-pinene, 3-carene, limonene and myrcene. y-terpinene was detected in emissions from pine but not from spruce. The relative amounts of different monoterpenes did not vary significantly with post-drying moisture content, but drying medium of higher temperature caused an increase in the relative amount of less volatile monoterpenes. The FID data is reported as concentration of VOC in the drying medium, and as weight VOC per odw. The concentration

  19. Understanding the fate and transport of petroleum hydrocarbons from coal tar within gasholders.

    Science.gov (United States)

    Coulon, Frédéric; Orsi, Roberto; Turner, Claire; Walton, Chris; Daly, Paddy; Pollard, Simon J T

    2009-02-01

    Coal tars have been identified as posing a threat to human health due to their toxic, mutagenic and carcinogenic characteristics. Workers involved in former gasholders decommissioning are potentially exposed to relevant concentrations of volatile and semi-volatile hydrocarbons upon opening up derelict tanks and during tar excavation/removal. While information on contaminated sites air-quality and its implications on medium-long term exposure is available, acute exposure issues associated with the execution of critical tasks are less understood. Calculations indicated that the concentration of a given contaminant in the gasholder vapour phase only depends on the coal tar composition, being only barely affected by the presence of water in the gasholder and the tar volume/void space ratio. Fugacity modelling suggested that risk-critical compounds such as benzene, naphthalene and other monocyclic and polycyclic aromatic hydrocarbons may gather in the gasholder air phase at significant concentrations. Gasholder emissions were measured on-site and compared with the workplace exposure limits (WELs) currently in use in UK. While levels for most of the toxic compounds were far lower than WELs, benzene air-concentrations where found to be above the accepted threshold. In addition due to the long exposure periods involved in gasholder decommissioning and the significant contribution given by naphthalene to the total coal tar vapour concentration, the adoption of a WEL for naphthalene may need to be considered to support operators in preventing human health risk at the workplace. The Level I fugacity approach used in this study demonstrated its suitability for applications to sealed environments such as gasholders and its further refining could provide a useful tool for land remediation risk assessors.

  20. Predicting Alkylate Yield and its Hydrocarbon Composition for Sulfuric Acid Catalyzed Isobutane Alkylation with Olefins Using the Method of Mathematical Modeling

    OpenAIRE

    Nurmakanova, А. Е.; Ivashkina, Elena Nikolaevna; Ivanchina, Emilia Dmitrievna; Dolganov, I. A.; Boychenko, S. S.

    2015-01-01

    The article provides the results of applied mathematical model of isobutane alkylation with olefins catalyzed by sulfuric acid to predict yield and hydrocarbon composition of alkylate caused by the changes in the feedstock composition and process parameters. It is shown that the alkylate produced from feedstock with less mass fraction of isobutane has lower octane value. Wherein the difference in composition of the feedstock contributes to antiknock index by the amount of 1.0-2.0 points.

  1. Modeling comprehensive chemical composition of weathered oil following a marine spill to predict ozone and potential secondary aerosol formation and constrain transport pathways

    Science.gov (United States)

    Drozd, Greg T.; Worton, David R.; Aeppli, Christoph; Reddy, Christopher M.; Zhang, Haofei; Variano, Evan; Goldstein, Allen H.

    2015-11-01

    Releases of hydrocarbons from oil spills have large environmental impacts in both the ocean and atmosphere. Oil evaporation is not simply a mechanism of mass loss from the ocean, as it also causes production of atmospheric pollutants. Monitoring atmospheric emissions from oil spills must include a broad range of volatile organic compounds (VOC), including intermediate-volatile and semivolatile compounds (IVOC, SVOC), which cause secondary organic aerosol (SOA) and ozone production. The Deepwater Horizon (DWH) disaster in the northern Gulf of Mexico during Spring/Summer of 2010 presented a unique opportunity to observe SOA production due to an oil spill. To better understand these observations, we conducted measurements and modeled oil evaporation utilizing unprecedented comprehensive composition measurements, achieved by gas chromatography with vacuum ultraviolet time of flight mass spectrometry (GC-VUV-HR-ToFMS). All hydrocarbons with 10-30 carbons were classified by degree of branching, number of cyclic rings, aromaticity, and molecular weight; these hydrocarbons comprise ˜70% of total oil mass. Such detailed and comprehensive characterization of DWH oil allowed bottom-up estimates of oil evaporation kinetics. We developed an evaporative model, using solely our composition measurements and thermodynamic data, that is in excellent agreement with published mass evaporation rates and our wind-tunnel measurements. Using this model, we determine surface slick samples are composed of oil with a distribution of evaporative ages and identify and characterize probable subsurface transport of oil.

  2. Emissions of volatile organic compounds (VOCs) from oil and natural gas activities: compositional comparison of 13 major shale basins via NOAA airborne measurements

    Science.gov (United States)

    Gilman, J.; Lerner, B. M.; Aikin, K. C.; De Gouw, J. A.; Koss, A.; Yuan, B.; Warneke, C.; Peischl, J.; Ryerson, T. B.; Holloway, J. S.; Graus, M.; Tokarek, T. W.; Isaacman-VanWertz, G. A.; Sueper, D.; Worsnop, D. R.

    2015-12-01

    The recent and unprecedented increase in natural gas production from shale formations is associated with a rise in the production of non-methane volatile organic compounds (VOCs) including natural gas plant liquids (e.g., ethane, propane, and butanes) and liquid lease condensate (e.g., pentanes, hexanes, aromatics and cycloalkanes). Since 2010, the production of natural gas liquids and the amount of natural gas vented/flared has increased by factors of ~1.28 and 1.57, respectively (U.S. Energy and Information Administration), indicating an increasingly large potential source of hydrocarbons to the atmosphere. Emission of VOCs may affect local and regional air quality due to the potential to form tropospheric ozone and organic particles as well as from the release of toxic species such as benzene and toluene. The 2015 Shale Oil and Natural Gas Nexus (SONGNex) campaign studied emissions from oil and natural gas activities across the central United States in order to better understand their potential air quality and climate impacts. Here we present VOC measurements from 19 research flights aboard the NOAA WP-3D over 11 shale basins across 8 states. Non-methane hydrocarbons were measured using an improved whole air sampler (iWAS) with post-flight analysis via a custom-built gas chromatograph-mass spectrometer (GC-MS). The whole air samples are complimented by higher-time resolution measurements of methane (Picarro spectrometer), ethane (Aerodyne spectrometer), and VOCs (H3O+ chemical ionization mass spectrometer). Preliminary analysis show that the Permian Basin on the New Mexico/Texas border had the highest observed VOC mixing ratios for all basins studied. We will utilize VOC enhancement ratios to compare the composition of methane and VOC emissions for each basin and the associated reactivities of these gases with the hydroxyl radical, OH, as a proxy for potential ozone formation.

  3. Compositional changes of aromatic steroid hydrocarbons in naturally weathered oil residues in the Egyptian western desert

    International Nuclear Information System (INIS)

    Barakat, A.O.; Qian, Y.; Kim, M.; Kennicutt, M.C. II

    2002-01-01

    Aromatic steranes are geochemical markers that can be used to study the maturation of organic matter of sediments and to correlate crude oils and source rocks. In this study, naturally weathered oil residues from an arid waste disposal site in Al-Alamein, Egypt, were analyzed for monoaromatic and triaromatic steranes to show the usefulness of biomarker compounds in assessing changes in chemical composition during the degradation of oil residues that have been released onto terrestrial environments. Gas chromatography and mass spectrometry were used to characterize the individual aromatic compounds. Results indicate that triaromatic sterane distributions are similar in oil residues with varying extents of weathering. The distribution correlated with a fresh crude oil sample from Western Desert-sourced oil. Molecular ratios of triaromatic sterane compounds were found to be suitable for source identification. The major changes in chemical compositions resulting from the weathering of the oil included the depletion of short chain mono- and tri-aromatic steranes in extremely weathered samples. The results of the triaromatic sterane distribution correspond with weathering classifications based on the analyses of saturated and aromatic hydrocarbons and the ratios of n-alkanes, polycyclic aromatic hydrocarbons, and saturate biomarker compounds. 15 refs., 3 tabs., 3 figs

  4. Effects of gamma irradiation on food contact polyethylene, polypropylene and polystyrene. Volatiles

    International Nuclear Information System (INIS)

    Kawamura, Yoko; Sayama, Kayo; Yamada, Takashi

    2000-01-01

    The effects of gamma irradiation on the generation of volatiles from food contact polyethylene and polypropylene were investigated using head space (HS)/GC/MS. All samples generated volatiles such as acetic acid, propionic acid, butanoic acid, 2,2-dimethylpropionic acid, acetone, 2-butanone, 2-propanol, 2-methyl-2-propanol, hydrocarbons, etc., due to the gamma irradiation. Especially, acetic acid and acetone were formed in greatest amounts. Since these volatiles did not exist before irradiation and their amounts increased with increasing irradiation dose, they should be degradation products from the polymer or additives by irradiation. Polypropylene generated more kinds and larger amounts of volatiles than polyethylene, which showed that polypropylene is more sensitive to irradiation. Polystyrene contained styrene and ethylbenzene as monomers before irradiation and their amounts decreased after irradiation. Polystyrene generated few degradation products during the irradiation. (author)

  5. Composition and method for coke retardant during hydrocarbon processing

    International Nuclear Information System (INIS)

    Reid, D.K.

    1988-01-01

    A process is described for inhibiting the formation and deposition of filamentous coke on metallic surfaces in contact with a hydrocarbon having a temperature of 600 0 -1300 0 F which comprises adding to the hydrocarbon a sufficient amount for the purpose of a boron compound selected from the group of boron oxide compounds, boric acid and metal borides, with the proviso that when boric acid is used, it is substantially free of water

  6. Chemical composition of volatiles from Opuntia littoralis, Opuntia ficus-indica, and Opuntia prolifera growing on Catalina Island, California.

    Science.gov (United States)

    Wright, Cynthia R; Setzer, William N

    2014-01-01

    The essential oils from the cladodes of Opuntia littoralis, Opuntia ficus-indica and Opuntia prolifera growing wild on Santa Catalina Island, California, were obtained by hydrodistillation and analysed by gas chromatography-mass spectrometry (GC-MS). Terpenoids were the dominant class of volatiles in O. littoralis, with the two main components being the furanoid forms of cis-linalool oxide (10.8%) and trans-linalool oxide (8.8%). Fatty acid-derived compounds dominated the essential oil of O. ficus-indica with linoleic acid (22.3%), palmitic acid (12.7%), lauric acid (10.5%) and myristic acid (4.2%) as major fatty acids. O. prolifera oil was composed of 46.6% alkanes and the primary hydrocarbon component was heptadecane (19.2%). Sixteen compounds were common to all the three Opuntia species.

  7. Studies concerning thermodynamics and kinetics of the absorption of halogenated hydrocarbons relevant to environment

    International Nuclear Information System (INIS)

    Weisweiler, W.; Eidam, K.; Winterbauer, H.

    1993-07-01

    In the context of the research project the scrubbing of air contaminated by peculiar volatile organic compounds was investigated using the absorption technique by means of high boiling organics as washing liquids. Eight chlorinated hydrocarbons well known from technical processes were chosen to be representative for the volatile organic compounds. Eleven absorption media were selected on the basis of their physical properties. For the determination of the solubility data of the absorption media due to chlorinated hydrocarbons, nitrogen as well as a mixture of nitrogen and oxygen were used as carrier gas. The influence of the dipole moment of the absorption media on the amount of solubility - expressed as enrichment factor - was studied, too. Concerning the technical application, the thermostability and the stability against diluted inorganic acids were studied as well. (orig.). 56 figs., 8 tabs., 63 refs [de

  8. Volatile components and continental material of planets

    International Nuclear Information System (INIS)

    Florenskiy, K.P.; Nikolayeva, O.V.

    1984-01-01

    It is shown that the continental material of the terrestrial planets varies in composition from planet to planet according to the abundances and composition of true volatiles (H 2 0, CO 2 , etc.) in the outer shells of the planets. The formation of these shells occurs very early in a planet's evolution when the role of endogenous processes is indistinct and continental materials are subject to melting and vaporizing in the absence of an atmosphere. As a result, the chemical properties of continental materials are related not only to fractionation processes but also to meltability and volatility. For planets retaining a certain quantity of true volatile components, the chemical transformation of continental material is characterized by a close interaction between impact melting vaporization and endogeneous geological processes

  9. Subsurface biogenic gas rations associated with hydrocarbon contamination

    International Nuclear Information System (INIS)

    Marrin, D.L.

    1991-01-01

    Monitoring the in situ bioreclamation of organic chemicals in soil is usually accomplished by collecting samples from selected points during the remediation process. This technique requires the installation and sampling of soil borings and does not allow for continuous monitoring. The analysis of soil vapor overlying hydrocarbon-contaminated soil and groundwater has been used to detect the presence of nonaqueous phase liquids (NAPL) and to locate low-volatility hydrocarbons that are not directly detected by more conventional soil gas methods. Such soil vapor sampling methods are adaptable to monitoring the in situ bioremediation of soil and groundwater contamination. This paper focuses on the use of biogenic gas ratio in detecting the presence of crude oil and gasoline in the subsurface

  10. Constraining the Volatile Regime of Primitive Somma-Vesuvius Magmas Based on the Compositions of Phenocrysts and Melt Inclusions

    Science.gov (United States)

    Danyushevsky, L. V.; Esposito, R.; De Vivo, B.; Redi, D.; Lima, A.; Bodnar, R. J.; Gurenko, A.

    2017-12-01

    The volcanic complex of Mt. Somma-Vesuvius is located in the Campanian Plain on east of Naples. We present the results of a mineralogical and melt inclusion studies of primitive volcanic products erupted during the last 2 magmatic cycles of Soma-Vesuvius, aimed at better understanding the volatile fluxes and eruptive behaviour of the volcano. Our results suggest that despite large differences in the compositions of the erupted magmas (from olivine-bearing basaltic lavas to leucite-bearing phonolites) and the eruption style (from plinian to strombolian), there was very little change in the nature of the parental magmas. Melt inclusions in olivine phenocrysts in all volcanic products and styles reveal the highest volatile contents in the most magnesian, early formed crystals (Fo90; H2O 4-5 wt%; CO2 3,000-4,000 ppm), decreasing to near 0 levels of concentrations in olivine Fo70. Major and trace element compositions of the clinopyroxene phenocrysts (Mg#92-70) also suggest a similar parental magma composition and similar liquid lines of decent for all Somma-Vesuvius eruptions. Our results are best explained by a model which relates the eruption style to the intensity of melt supply under the volcano. High intensity plinian eruptions occur after a prolonged repose time, whereas strombolian eruptions occur during periods of more frequent volcanic activity [1]. We will also discuss possible implications for the role of carbonate assimilation during magma evolution of Somma-Vesuvius and for total volatile budget of the SOmma-Vesuvius eruptions. [1] [42] Lima, A., Danyushevsky, L.V., De Vivo, B. and Fedele, L. 2003: A model for the evolution of the Mt. Somma-Vesuvius magmatic system based on fluid and melt inclusion investigations. In: Melt Inclusions in volcanic systems: Methods, applications and Problems (B. De Vivo & R.J. Bodnar, Eds), Series: Developments in Volcanology. No. 5 Elsevier, Amsterdam, 227-251

  11. Wintertime hygroscopicity and volatility of ambient urban aerosol particles

    Directory of Open Access Journals (Sweden)

    J. Enroth

    2018-04-01

    Full Text Available Hygroscopic and volatile properties of atmospheric aerosol particles with dry diameters of (20, 50, 75, 110 and 145 nm were determined in situ by using a volatility–hygroscopicity tandem differential mobility analyser (VH-TDMA system with a relative humidity of 90 % and denuding temperature of 270 °C in central Budapest during 2 months in winter 2014–2015. The probability density function of the hygroscopic growth factor (HGF showed a distinct bimodal distribution. One of the modes was characterised by an overall mean HGF of approximately 1.07 (this corresponds to a hygroscopicity parameter κ of 0.033 independently of the particle size and was assigned to nearly hydrophobic (NH particles. Its mean particle number fraction was large, and it decreased monotonically from 69 to 41 % with particle diameter. The other mode showed a mean HGF increasing slightly from 1.31 to 1.38 (κ values from 0.186 to 0.196 with particle diameter, and it was attributed to less hygroscopic (LH particles. The mode with more hygroscopic particles was not identified. The probability density function of the volatility GF (VGF also exhibited a distinct bimodal distribution with an overall mean VGF of approximately 0.96 independently of the particle size, and with another mean VGF increasing from 0.49 to 0.55 with particle diameter. The two modes were associated with less volatile (LV and volatile (V particles. The mean particle number fraction for the LV mode decreased from 34 to 21 % with particle diameter. The bimodal distributions indicated that the urban atmospheric aerosol contained an external mixture of particles with a diverse chemical composition. Particles corresponding to the NH and LV modes were assigned mainly to freshly emitted combustion particles, more specifically to vehicle emissions consisting of large mass fractions of soot likely coated with or containing some water-insoluble organic compounds such as non

  12. Measurement of volatiles, semi-volatiles and heavy metals in an oil burn test

    International Nuclear Information System (INIS)

    Li, K.; Caron, T.; Landriault, M.; Pare, J.R.J.; Fingas, M.

    1992-01-01

    Tests involving meso-scale burning of Louisiana crude oil were conducted, and during each burn, extensive samples were taken from the oil, residue, and the smoke plume. The detailed analytical work employed to obtain and analyze the burn samples is outlined and discussed. The analytical parameters included volatiles and semi-volatiles of environmental interests as well as heavy metals typically contained in the starting crude oil. Because the smoke plume did not always impinge on the samplers, the ground samplers did not collect sufficient samples for a definitive analysis. Crude/residue analyses showed the burn resulted in a significant reduction of polycyclic aromatic hydrocarbons (PAH) in the original oil. Most of the reduction was thought to be simply evaporation or destruction from combustion. The residue did not have the degree of enrichment of the higher molecular weight PAHs as was the case in bench-scale burn experiments. Volatile organic compound and dioxin/furan measurements likewise did not show high levels of contamination from the burn itself. Most of the elevated levels of contaminants could probably be due to evaporation of the oil itself. Insufficient sampling was conducted to investigate the background levels from the weathering process. A novel means of sampling using a small remote controlled helicopter was attempted and sufficiently interesting results were obtained to indicate the potential of this passive sampling device for future work. 5 refs., 4 figs

  13. Priority volatile organic compounds in surface waters of the southern North Sea

    International Nuclear Information System (INIS)

    Huybrechts, Tom; Dewulf, Jo; Langenhove, Herman van

    2005-01-01

    The occurrence of 25 volatile organic compounds (VOCs) was studied from April 1998 to October 2000 in the southern North Sea. Target VOCs were selected from lists of priority pollutants for the marine environment and included, e.g., chlorinated short-chain hydrocarbons (CHCs), monocyclic aromatic hydrocarbons (MAHs), and chlorinated monocyclic aromatic hydrocarbons (CMAHs). Water samples were taken from the Channel, the Belgian Continental Shelf, the mouth of the Scheldt estuary and the Southern Bight, and were analysed by purge-and-trap and high-resolution gas chromatography-mass spectrometry. All data were produced by analyses deemed 'in control' by a rigorous quality assurance/quality control program provided by QUASIMEME (Quality Assurance of Information for Marine Environmental Monitoring in Europe). Chloroform and trichloroethene were commonly detected at concentrations up to 1900 and 270 ng l -1 , respectively. The other CHCs were generally found below 5 ng l -1 , and rarely exceeded 10 ng l -1 . Concentrations of MAHs were at least one order of magnitude higher than those of the CHCs. The higher levels were attributed to anthropogenic emissions from oil-related activities in coastal areas. CMAHs, except chlorobenzene and 1,4-dichlorobenzene, were hardly detected in North Sea waters. The levels of several CHCs and MAHs were shown to decrease compared to previous investigations in 1994-1995, probably as a result of on-going emission reduction efforts. The occurrence of 1,1,1-trichloroethane, for instance, was substantially reduced since the Montreal Protocol was implemented in 1995. - Volatile aromatics are a major group of volatile organic compounds in the North Sea, and are attributed to discharges from shipping and oil related activities

  14. Enhanced biodegradation of hydrocarbons in-situ via bioventing

    International Nuclear Information System (INIS)

    Newman, B.; Martinson, M.; Smith, G.; McCain, L.

    1993-01-01

    This case study discusses the remediation of soils beneath a former service station impacted with volatile and semi-volatile petroleum compounds. Subsurface investigation revealed hydrocarbon contamination representative of weathered gasoline and diesel fuel in a stratified soil profile consisting of sand and silts. Only unsaturated soils were contaminated with no impact to ground water. A bioventing corrective action approach was selected which included excavation of 6,100 cubic yards of impacted soils with soil mixing to add inorganic nutrients and eliminate soil heterogeneities. Soils were then returned to the excavation after forced-air ventilation lateral lines were installed at the floor of the excavation. Soil vapor concentrations of benzene, toluene, ethylbenzene, xylenes (BTEX) rapidly declined within the first three months of system operation to nondetectable levels

  15. Effects of mechanical wounding on essential oil composition and emission of volatiles from Minthostachys mollis.

    Science.gov (United States)

    Banchio, Erika; Zygadlo, Julio; Valladares, Graciela R

    2005-04-01

    Plant tissues may show chemical changes following damage. This possibility was analyzed for Minthostachys mollis, a Lamiaceae native to Central Argentina with medicinal and aromatic uses in the region. Effects of mechanical damage on its two dominant monoterpenes, pulegone and menthone, were analyzed by perforating M. mollis leaves and then assessing essential oil composition at 24, 48, and 120 hr; emission of volatiles was also measured 24 and 48 hr after wounding. Mechanical damage resulted in an increase of pulegone and menthone concentration in M. mollis essential oil during the first 24 hr. These changes did not occur in the adjacent undamaged leaves, suggesting a lack of systemic response. Postwounding changes in the volatiles released from M. mollis damaged leaves were also detected, most noticeably showing an increase in the emission of pulegone. Inducible chemical changes in aromatic plants might be common and widespread, affecting the specific compounds on which commercial exploitation is based.

  16. The Composition of Cigarette Smoke: A Catalogue of the Polycyclic Aromatic Hydrocarbons

    Directory of Open Access Journals (Sweden)

    Rodgman A

    2014-12-01

    Full Text Available Classified as toxicants in many of the substances to which humans are exposed are the polycyclic aromatic hydrocarbons (PAHs. Such exposures include air pollutants from a variety of sources, foodstuffs and beverages, and tobacco smoke. Since the early 1950s, the composition of the latter has been more completely defined than that of any other consumer product. Nearly 4800 components have been identified in tobacco smoke and among these are over 500 PAHs either completely or partially identified. Because of the tumorigenicity of many PAHs, much research has been conducted in attempts to define the relationship between the PAH structures and their specific tumorigenicities in laboratory animals. None of the theories to date completely answers all the questions.

  17. Volatile Metabolomic Composition of Vitex Species: Chemodiversity Insights and Acaricidal Activity

    Directory of Open Access Journals (Sweden)

    José G. de Sena Filho

    2017-11-01

    Full Text Available The Vitex genus (Lamiaceae produces a plethora of metabolites that include ecdysteroids and terpenoids, some of which have demonstrated insect repellent properties. The volatile composition of several members of this genus has not been chemically defined, as many taxa are endemic to remote ecosystems. In this study, leaves were collected from the northeast of Brazil from Vitex capitata, V. megapotamica, V. gardneriana, and V. rufescens plants and examined for their chemical profile via GC-MS/FID of essential oil extracts. The analyses showed a diversity of terpenoids. Of particular note were seven-member ring sesquiterpenes which were present in great abundance; a dendrogram showed clades separating by the production of bicyclogermacrene, aromadendrane and 5,10-cycloaromadendrane sesquiterpenoids for the four species. Comparison of volatile metabolite profiles to 13 other Vitex species showed strong similarities in the production of some monoterpenes, but varied by their production of larger terpenes, especially those with gem-dimethylcyclopropyl subunits on seven-member ring compounds. From this work, we suggest that the sesquiterpene skeleton with seven member rings is a good chemosystematic biomarker candidate for the Vitex genus. Separation using this biomarker was then validated using Inter-Simple Sequence Repeat profiling. Lastly, experiments examining the toxicity of these four oils against the coconut mite Aceria guerreronis showed that only the oil of V. gardneriana had strong acaricidal activity, with an LC50 of 0.85 mg/mL, thus demonstrating its potential for use as a natural pesticide.

  18. Comparative analysis of juice volatiles in selected mandarins, mandarin relatives and other citrus genotypes.

    Science.gov (United States)

    Yu, Yuan; Bai, Jinhe; Chen, Chunxian; Plotto, Anne; Baldwin, Elizabeth A; Gmitter, Frederick G

    2018-02-01

    Citrus fruit flavor is an important attribute prioritized in variety improvement. The present study compared juice volatiles compositions from 13 selected citrus genotypes, including six mandarins (Citrus reticulata), three sour oranges (Citrus aurantium), one blood orange (Citrus sinensis), one lime (Citrus limonia), one Clementine (Citrus clementina) and one satsuma (Citrus unshiu). Large differences were observed with respect to volatile compositions among the citrus genotypes. 'Goutou' sour orange contained the greatest number of volatile compounds and the largest volatile production level. 'Ponkan' mandarin had the smallest number of volatiles and 'Owari' satsuma yielded the lowest volatile production level. 'Goutou' sour orange and 'Moro' blood orange were clearly distinguished from other citrus genotypes based on the analysis of volatile compositions, even though they were assigned into one single group with two other sour oranges by the molecular marker profiles. The clustering analysis based on the aroma volatile compositions was able to differentiate mandarin varieties and natural sub-groups, and was also supported by the molecular marker study. The gas chromatography-mass spectrometry analysis of citrus juice aroma volatiles can be used as a tool to distinguish citrus genotypes and assist in the assessment of future citrus breeding programs. The aroma volatile profiles of the different citrus genotypes and inter-relationships detected among volatile compounds and among citrus genotypes will provide fundamental information on the development of marker-assisted selection in citrus breeding. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  19. The use of solvent extractions and solubility theory to discern hydrocarbon associations in coal, with application to the coal-supercritical CO2 system

    Science.gov (United States)

    Kolak, Jonathan J.; Burruss, Robert A.

    2014-01-01

    Samples of three high volatile bituminous coals were subjected to parallel sets of extractions involving solvents dichloromethane (DCM), carbon disulfide (CS2), and supercritical carbon dioxide (CO2) (40 °C, 100 bar) to study processes affecting coal–solvent interactions. Recoveries of perdeuterated surrogate compounds, n-hexadecane-d34 and four polycyclic aromatic hydrocarbons (PAHs), added as a spike prior to extraction, provided further insight into these processes. Soxhlet-DCM and Soxhlet-CS2 extractions yielded similar amounts of extractable organic matter (EOM) and distributions of individual hydrocarbons. Supercritical CO2 extractions (40 °C, 100 bar) yielded approximately an order of magnitude less EOM. Hydrocarbon distributions in supercritical CO2 extracts generally mimicked distributions from the other solvent extracts, albeit at lower concentrations. This disparity increased with increasing molecular weight of target hydrocarbons. Five- and six-ring ring PAHs generally were not detected and no asphaltenes were recovered in supercritical CO2 extractions conducted at 40 °C and 100 bar. Supercritical CO2 extraction at elevated temperature (115 °C) enhanced recovery of four-ring and five-ring PAHs, dibenzothiophene (DBT), and perdeuterated PAH surrogate compounds. These results are only partially explained through comparison with previous measurements of hydrocarbon solubility in supercritical CO2. Similarly, an evaluation of extraction results in conjunction with solubility theory (Hildebrand and Hansen solubility parameters) does not fully account for the hydrocarbon distributions observed among the solvent extracts. Coal composition (maceral content) did not appear to affect surrogate recovery during CS2 and DCM extractions but might affect supercritical CO2 extractions, which revealed substantive uptake (partitioning) of PAH surrogates into the coal samples. This uptake was greatest in the sample (IN-1) with the highest vitrinite content. These

  20. The occurrence of selected hydrocarbons in food on sale at petrol station shops and comparison with food from other shops: a literature survey

    NARCIS (Netherlands)

    Wolf, J.M. de; Beld, C.M.B. van den; Gennart, J.-Ph.; Riley, A.J.; Urbanus, J.

    2000-01-01

    A review of reports on the occurrence of some hydrocarbons in food in relation to the sales location, with emphasis on petrol station shops, covers the principal selected hydrocarbons, i.e., volatile components of gasoline, e.g., benzene, pentane, hexane, toluene, MTBE, and xylene; relevance of

  1. Halogenated hydrocarbons - an environmental problem

    Energy Technology Data Exchange (ETDEWEB)

    Schoeler, H F; Thofern, E

    1984-01-01

    The paper provides a survey of the incidence of highly volatile halogenated hydrocarbons in ground, surface and drinking water as well as in the snows of Western Germany. Almost the entire production of chlorinated solvents is released into the environment. The absorption media are mostly soil, water and atmosphere. Whereas in the atmosphere elimination reactions take place, solvents that have passed the soil get into the ground water owing to their persistence and can cause considerable pollutions of drinking water. Moreover haloforms may occur in drinking water, which are produced during chlorine disinfection of pre-treated water.

  2. Changes in the Composition of Aromatherapeutic Citrus Oils during Evaporation

    Directory of Open Access Journals (Sweden)

    George W. Francis

    2015-01-01

    Full Text Available The composition of some commercial Citrus oils, lemon, sweet orange, and tangerine, designated for aromatherapy, was examined before and after partial evaporation in a stream of nitrogen. The intact oils contained the expected mixtures of mono- and sesquiterpenes, with hydrocarbons dominating and lesser amounts of oxygenated analogues making up the remainder. Gas chromatography-mass spectrometry was used to follow alterations in the relative amounts of the various components present as evaporation proceeded. Changes were marked, and in particular more volatile components present in the intact oils rapidly disappeared. Thus the balance of content was shifted away from monoterpene hydrocarbons towards the analogous alcohols and carbonyl compounds. The results of this differential evaporation are discussed and possible consequences for aromatherapy use are noted. The case of lemon oil was especially interesting as the relative amount of citral, a known sensitizer, remaining as time elapsed represented an increasing percentage of the total oil.

  3. Compostos voláteis em méis florais Volatile compounds in floral honeys

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Bastos De Maria

    2003-01-01

    Full Text Available A review about origin, composition and importance of volatile compounds in floral honeys is presented. Hydrocarbons, aromatic components, acids, diacids, terpenoids, ketones, aldehydes, esters and alcohols have been found in honey aroma of different botanical origin. Cis-rose oxide has been proposed as an indicator for Tilia cordata honey. Citrus honeys are known to contain methyl anthranilate, a compound which other honeys virtually lack. Linalool, phenylethylalcohol, phenylacetaldehyde, p-anisaldehyde and benzaldehyde are important contributors for the aroma of different unifloral honeys. Both isovaleric acid, gama-decalactone and benzoic acid appears to be important odourants for Anarcadium occidentale and Croton sp. honeys from Brazil. The furfurylmercaptan, benzyl alcohol, delta-octalactone, eugenol, phenylethylalcohol and guaiacol appear to be only relevant compounds for Anarcadium occidentale. The vanillin was considered an important odourant only for Croton sp..

  4. Evolution of Hydrocarbon-Degrading Microbial Communities in the Aftermath of the Deepwater Horizon Oil Well Blowout in the Gulf of Mexico

    Science.gov (United States)

    Andersen, G.; Dubinsky, E. A.; Chakraborty, R.; Hollibaugh, J. T.; Hazen, T. C.

    2012-12-01

    The Deepwater Horizon oil spill created large plumes of dispersed oil and gas that remained deep in the water column and stimulated growth of several deep-sea bacteria that can degrade hydrocarbons at cold temperatures. We tracked microbial community composition before, during and after the 83-day spill to determine relationships between microbial dynamics, and hydrocarbon and dissolved-oxygen concentrations. Dominant bacteria in plumes shifted drastically over time and were dependent on the concentration of hydrocarbons, and the relative quantities of insoluble and soluble oil fractions. Unmitigated flow from the wellhead early in the spill resulted in the highest concentrations of oil and relatively more n-alkanes suspended in the plume as small oil droplets. These conditions resulted in near complete dominance by alkane-degrading Oceanospirillales, Pseudomonas and Shewanella. Six-weeks into the spill overall hydrocarbon concentrations in the plume decreased and were almost entirely composed of BTEX after management actions reduced emissions into the water column. These conditions corresponded with the emergence of Colwellia, Pseudoalteromonas, Cycloclasticus and Halomonas that are capable of degrading aromatic compounds. After the well was contained dominant plume bacteria disappeared within two weeks after the spill and transitioned to an entirely different set of bacteria dominated by Flavobacteria, Methylophaga, Alteromonas and Rhodobacteraceae that were found in anomalous oxygen depressions throughout August and are prominent degraders of both high molecular weight organic matter as well as hydrocarbons. Bio-Sep beads amended with volatile hydrocarbons from MC-252 oil were used from August through September to create hydrocarbon-amended traps for attracting oil-degrading microbes in situ. Traps were placed at multiple depths on a drilling rig about 600-m from the original MC-252 oil spill site. Microbes were isolated on media using MC-252 oil as the sole

  5. Comparison analysis of volatiles from the leaves and flowers of four saururaceae species

    International Nuclear Information System (INIS)

    Yang, Z.H.; Sun, Y.M.; Sun, M.

    2015-01-01

    Saururaceae (lizard's tail family) comprises three genera and four species (Saururus chinensis (Loureiro) Baillon. (SC), Gymnotheca chinensis Decne. (GC), Gymnotheca involucrata Pei. (GI) and Houttuynia cordata Thunberg. (HC)) in eastern Asia, and they extend from the most primitive to the most evolutionary levels. The purpose of this study is to examine whether and to what extent the diversity of volatiles can support the accepted evolutionary scheme in Saururaceae for the four species. Volatiles from fresh leaves and flowers of Saururaceae species from different regions were analyzed comparatively by gas chromatography-mass spectrometry (GC-MS). The samples studied showed differences in the volatile profiles of leaves and flowers among the species. In the leaves and flowers, concentrations of all monoterpenes and oxides, all alcohols, all acids and all esters were highest in SC, lowest in HC, and the concentrations of these components for GC and GI were between those of SC and HC. Concentrations of all sesquiterpenes and oxides, all straight chain aliphatic hydrocarbons, all branched aliphatic hydrocarbons, all aldehydes, and all ketones were lowest in SC, highest in HC and the concentrations of these components for GC and GI were between those of SC and HC. The results in this study could support the accepted taxonomical scheme of four species in Saururaceae. (author)

  6. Site-specific probabilistic ecological risk assessment of a volatile chlorinated hydrocarbon-contaminated tidal estuary.

    Science.gov (United States)

    Hunt, James; Birch, Gavin; Warne, Michael St J

    2010-05-01

    Groundwater contaminated with volatile chlorinated hydrocarbons (VCHs) was identified as discharging to Penrhyn Estuary, an intertidal embayment of Botany Bay, New South Wales, Australia. A screening-level hazard assessment of surface water in Penrhyn Estuary identified an unacceptable hazard to marine organisms posed by VCHs. Given the limitations of hazard assessments, the present study conducted a higher-tier, quantitative probabilistic risk assessment using the joint probability curve (JPC) method that accounted for variability in exposure and toxicity profiles to quantify risk (delta). Risk was assessed for 24 scenarios, including four areas of the estuary based on three exposure scenarios (low tide, high tide, and both low and high tides) and two toxicity scenarios (chronic no-observed-effect concentrations [NOEC] and 50% effect concentrations [EC50]). Risk (delta) was greater at low tide than at high tide and varied throughout the tidal cycle. Spatial distributions of risk in the estuary were similar using both NOEC and EC50 data. The exposure scenario including data combined from both tides was considered the most accurate representation of the ecological risk in the estuary. When assessing risk using data across both tides, the greatest risk was identified in the Springvale tributary (delta=25%)-closest to the source area-followed by the inner estuary (delta=4%) and the Floodvale tributary (delta=2%), with the lowest risk in the outer estuary (delta=0.1%), farthest from the source area. Going from the screening level ecological risk assessment (ERA) to the probabilistic ERA changed the risk from unacceptable to acceptable in 50% of exposure scenarios in two of the four areas within the estuary. The probabilistic ERA provided a more realistic assessment of risk than the screening-level hazard assessment. Copyright (c) 2010 SETAC.

  7. Induction of stress volatiles and changes in essential oil content and composition upon microwave exposure in the aromatic plant Ocimum basilicum

    Energy Technology Data Exchange (ETDEWEB)

    Lung, Ildikó [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat Street, Cluj-Napoca 400293 (Romania); Soran, Maria-Loredana, E-mail: loredana.soran@itim-cj.ro [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat Street, Cluj-Napoca 400293 (Romania); Opriş, Ocsana; Truşcă, Mihail Radu Cătălin [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat Street, Cluj-Napoca 400293 (Romania); Niinemets, Ülo [Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, 1 Kreutzwaldi Street, Tartu 51014 (Estonia); Copolovici, Lucian [Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, 1 Kreutzwaldi Street, Tartu 51014 (Estonia); Institute of Technical and Natural Sciences Research-Development of “Aurel Vlaicu” University, 2 Elena Drăgoi Street, Arad 310330 (Romania)

    2016-11-01

    Exposure to sustained low intensity microwaves can constitute a stress for the plants, but its effects on plant secondary chemistry are poorly known. We studied the influence of GSM and WLAN-frequency microwaves on emissions of volatile organic compounds and content of essential oil in the aromatic plant Ocimum basilicum L. hypothesizing that microwave exposure leads to enhanced emissions of stress volatiles and overall greater investment in secondary compounds. Compared to the control plants, microwave irradiation led to decreased emissions of β-pinene, α-phellandrene, bornyl acetate, β-myrcene, α-caryophyllene and benzaldehyde, but increased emissions of eucalyptol, estragole, caryophyllene oxide, and α-bergamotene. The highest increase in emission, 21 times greater compared to control, was observed for caryophyllene oxide. The irradiation resulted in increases in the essential oil content, except for the content of phytol which decreased by 41% in the case of GSM-frequency, and 82% in the case of WLAN-frequency microwave irradiation. The strongest increase in response to WLAN irradiation, > 17 times greater, was observed for hexadecane and octane contents. Comparisons of volatile compositions by multivariate analyses demonstrated a clear separation of different irradiance treatments, and according to the changes in the volatile emissions, the WLAN-frequency irradiation represented a more severe stress than the GSM-frequency irradiation. Overall, these results demonstrating important modifications in the emission rates, essential oil content and composition indicate that microwave irradiation influences the quality of herbage of this economically important spice plant. - Highlights: • Microwave irradiation represents a stress for the plants. • Microwave exposure leads to enhanced emissions of stress volatiles. • O. basilicum irradiation with microwaves increases the essential oil content. • Microwave pollution can constitute a threat to the

  8. Induction of stress volatiles and changes in essential oil content and composition upon microwave exposure in the aromatic plant Ocimum basilicum

    International Nuclear Information System (INIS)

    Lung, Ildikó; Soran, Maria-Loredana; Opriş, Ocsana; Truşcă, Mihail Radu Cătălin; Niinemets, Ülo; Copolovici, Lucian

    2016-01-01

    Exposure to sustained low intensity microwaves can constitute a stress for the plants, but its effects on plant secondary chemistry are poorly known. We studied the influence of GSM and WLAN-frequency microwaves on emissions of volatile organic compounds and content of essential oil in the aromatic plant Ocimum basilicum L. hypothesizing that microwave exposure leads to enhanced emissions of stress volatiles and overall greater investment in secondary compounds. Compared to the control plants, microwave irradiation led to decreased emissions of β-pinene, α-phellandrene, bornyl acetate, β-myrcene, α-caryophyllene and benzaldehyde, but increased emissions of eucalyptol, estragole, caryophyllene oxide, and α-bergamotene. The highest increase in emission, 21 times greater compared to control, was observed for caryophyllene oxide. The irradiation resulted in increases in the essential oil content, except for the content of phytol which decreased by 41% in the case of GSM-frequency, and 82% in the case of WLAN-frequency microwave irradiation. The strongest increase in response to WLAN irradiation, > 17 times greater, was observed for hexadecane and octane contents. Comparisons of volatile compositions by multivariate analyses demonstrated a clear separation of different irradiance treatments, and according to the changes in the volatile emissions, the WLAN-frequency irradiation represented a more severe stress than the GSM-frequency irradiation. Overall, these results demonstrating important modifications in the emission rates, essential oil content and composition indicate that microwave irradiation influences the quality of herbage of this economically important spice plant. - Highlights: • Microwave irradiation represents a stress for the plants. • Microwave exposure leads to enhanced emissions of stress volatiles. • O. basilicum irradiation with microwaves increases the essential oil content. • Microwave pollution can constitute a threat to the

  9. Studies on the effect of petroleum hydrocarbon on the microbial and ...

    African Journals Online (AJOL)

    SERVER

    2007-08-20

    Aug 20, 2007 ... Key words: Hydrocarbon, microbial counts, physico-chemical characteristics. INTRODUCTION. Petroleum ... carbons, whose composition also varies with the source. ... hydrocarbons into aquifers can lead to concentrations of.

  10. Speciated measurements of semivolatile and intermediate volatility organic compounds (S/IVOCs in a pine forest during BEACHON-RoMBAS 2011

    Directory of Open Access Journals (Sweden)

    A. W. H. Chan

    2016-02-01

    Full Text Available Understanding organic composition of gases and particles is essential to identifying sources and atmospheric processing leading to organic aerosols (OA, but atmospheric chemical complexity and the analytical techniques available often limit such analysis. Here we present speciated measurements of semivolatile and intermediate volatility organic compounds (S/IVOCs using a novel dual-use instrument (SV-TAG-AMS deployed at Manitou Forest, CO, during the Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics & Nitrogen – Rocky Mountain Biogenic Aerosol Study (BEACHON-RoMBAS 2011 campaign. This instrument provides on-line speciation of ambient organic compounds with 2 h time resolution. The species in this volatility range are complex in composition, but their chemical identities reveal potential sources. Observed compounds of biogenic origin include sesquiterpenes with molecular formula C15H24 (e.g., β-caryophyllene and longifolene, which were most abundant at night. A variety of other biogenic compounds were observed, including sesquiterpenoids with molecular formula C15H22, abietatriene and other terpenoid compounds. Many of these compounds have been identified in essential oils and branch enclosure studies but were observed in ambient air for the first time in our study. Semivolatile polycyclic aromatic hydrocarbons (PAHs and alkanes were observed with highest concentrations during the day and the dependence on temperature suggests the role of an evaporative source. Using statistical analysis by positive matrix factorization (PMF, we classify observed S/IVOCs by their likely sources and processes, and characterize them based on chemical composition. The total mass concentration of elutable S/IVOCs was estimated to be on the order of 0.7 µg m−3 and their volatility distributions are estimated for modeling aerosol formation chemistry.

  11. Supercritical fluid extraction of hydrocarbons and 2-alkylcyclobutanones for the detection of irradiated foodstuffs

    NARCIS (Netherlands)

    Horvatovich, P; Miesch, M; Hasselmann, C; Marchioni, E

    2000-01-01

    Supercritical carbon dioxide can be used to carry out a selective and fast extraction (30 min) of volatile hydrocarbons and 2-alkylcyclobutanones contained in irradiated foods. After elimination of the traces of triglycerides still contained in the extracts on a silica column, the compounds were

  12. Analysis of the radiolytic products on high-dose irradiated food and packing materials

    International Nuclear Information System (INIS)

    Kim, Kyong Su; Shim, Sung Lye; Chung, In Sun

    2010-04-01

    The aims of this study were to prepare the government approval for the extension of food irradiation item to food or its products, to promote the industrial application of radiation technology, and to apply basic data in policy for introduction of irradiation. The change of hydrocarbons by irradiation was evaluated for the detection of irradiated meat. The results showed that hydrocarbons were detected in all of irradiated samples, but these hydrocarbons were not detected in non-irradiated samples. There were no difference between vacuum and N 2 - packaging. According to fatty acid compounds and degradation pathway of beef and pork, it could be deliberated that a great amount of produced hydrocarbons such as 8-heptadenene and 1,7-hexadecadien were able to be used as identification factor of irradiated meat. Effects of γ-irradiation on the volatile organic compounds in agricultural products were determined by analyzing changes of volatile composition. The composition of volatile organic compounds were little changed, but few specific compounds induced by γ-irradiation were identified. The variations of concentration in irradiated samples identified in this study could be due to the radiation sensitivity of compounds with the dose used. Effects of γ-irradiation on the volatile compounds in packaging materials were determined by analyzing changes of volatile composition. In polyethylene and polypropylene, 1,3-DBB was identified only in irradiated samples. Levels of 1,3-DBB increased with increasing irradiation doses. These results suggest may be useful in evaluation of γ-irradiation effects on food packaging materials

  13. Analysis of the radiolytic products on high-dose irradiated food and packing materials

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyong Su; Shim, Sung Lye; Chung, In Sun [Chosun University, Gwangju (Korea, Republic of)

    2010-04-15

    The aims of this study were to prepare the government approval for the extension of food irradiation item to food or its products, to promote the industrial application of radiation technology, and to apply basic data in policy for introduction of irradiation. The change of hydrocarbons by irradiation was evaluated for the detection of irradiated meat. The results showed that hydrocarbons were detected in all of irradiated samples, but these hydrocarbons were not detected in non-irradiated samples. There were no difference between vacuum and N{sub 2}- packaging. According to fatty acid compounds and degradation pathway of beef and pork, it could be deliberated that a great amount of produced hydrocarbons such as 8-heptadenene and 1,7-hexadecadien were able to be used as identification factor of irradiated meat. Effects of {gamma}-irradiation on the volatile organic compounds in agricultural products were determined by analyzing changes of volatile composition. The composition of volatile organic compounds were little changed, but few specific compounds induced by {gamma}-irradiation were identified. The variations of concentration in irradiated samples identified in this study could be due to the radiation sensitivity of compounds with the dose used. Effects of {gamma}-irradiation on the volatile compounds in packaging materials were determined by analyzing changes of volatile composition. In polyethylene and polypropylene, 1,3-DBB was identified only in irradiated samples. Levels of 1,3-DBB increased with increasing irradiation doses. These results suggest may be useful in evaluation of {gamma}-irradiation effects on food packaging materials

  14. Volatile monoterpenes in a stand of Picea abies (L.) Karst

    International Nuclear Information System (INIS)

    Schuermann, W.; Eichstaedter, G.; Steinbrecher, R.; Schoenwitz, R.; Gabriel, R.; Karbach, I.; Zufall, N.; Ziegler, H.

    1992-01-01

    Natural emissions of terpene and their fate in the atmosphere were investigated in a forest stand of the Bayerischer Wald mountains. Terpenes are volatile hydrocarbons whose relevance for air chemistry has increased considerably in the past few years. The investigation compared different sources of terpene in order to determine their strength as a function of meteorological, air-chemical and biological parameters. (orig./BBR) [de

  15. Effect of Gamma-Irradiation on the Volatile Flavor Compounds from Dried Ginger (Zingiber officinale Roscoe)

    International Nuclear Information System (INIS)

    No, K.M.; Seo, H.Y.; Gyawali, Rajendra; Shim, S.L.; Yang, S.H.; Lee, S.J.; Kim, K.S.

    2005-01-01

    The effect of gamma irradiation on volatile components of Korean dried ginger (Zingiber officinale Roscoe) was studied and compared with non-irradiated sample. Volatile compounds from non- and irradiated samples were extracted using simultaneous distillation-extraction (SDE) apparatus and analyzed by gas chromatography-mass spectrometer (GC/MS). A total of 83 and 71 compounds were identified and quantified from non-and irradiated dried ginger at dose of 10 kGy. Identified components were hydrocarbons, alcohols, aldehydes, esters, ketones and miscellaneous compounds

  16. Silicon isotopes in angrites and volatile loss in planetesimals

    Science.gov (United States)

    Moynier, Frédéric; Savage, Paul S.; Badro, James; Barrat, Jean-Alix

    2014-01-01

    Inner solar system bodies, including the Earth, Moon, and asteroids, are depleted in volatile elements relative to chondrites. Hypotheses for this volatile element depletion include incomplete condensation from the solar nebula and volatile loss during energetic impacts. These processes are expected to each produce characteristic stable isotope signatures. However, processes of planetary differentiation may also modify the isotopic composition of geochemical reservoirs. Angrites are rare meteorites that crystallized only a few million years after calcium–aluminum-rich inclusions and exhibit extreme depletions in volatile elements relative to chondrites, making them ideal samples with which to study volatile element depletion in the early solar system. Here we present high-precision Si isotope data that show angrites are enriched in the heavy isotopes of Si relative to chondritic meteorites by 50–100 ppm/amu. Silicon is sufficiently volatile such that it may be isotopically fractionated during incomplete condensation or evaporative mass loss, but theoretical calculations and experimental results also predict isotope fractionation under specific conditions of metal–silicate differentiation. We show that the Si isotope composition of angrites cannot be explained by any plausible core formation scenario, but rather reflects isotope fractionation during impact-induced evaporation. Our results indicate planetesimals initially formed from volatile-rich material and were subsequently depleted in volatile elements during accretion. PMID:25404309

  17. Studies of volatiles and organic materials in early terrestrial and present-day outer solar system environments

    Science.gov (United States)

    Sagan, Carl; Thompson, W. Reid; Chyba, Christopher F.; Khare, B. N.

    1991-01-01

    A review and partial summary of projects within several areas of research generally involving the origin, distribution, chemistry, and spectral/dielectric properties of volatiles and organic materials in the outer solar system and early terrestrial environments are presented. The major topics covered include: (1) impact delivery of volatiles and organic compounds to the early terrestrial planets; (2) optical constants measurements; (3) spectral classification, chemical processes, and distribution of materials; and (4) radar properties of ice, hydrocarbons, and organic heteropolymers.

  18. Supercritical fluid extraction of volatile and non-volatile compounds from Schinus molle L.

    Directory of Open Access Journals (Sweden)

    M. S. T. Barroso

    2011-06-01

    Full Text Available Schinus molle L., also known as pepper tree, has been reported to have antimicrobial, antifungal, anti-inflammatory, antispasmodic, antipyretic, antitumoural and cicatrizing properties. This work studies supercritical fluid extraction (SFE to obtain volatile and non-volatile compounds from the aerial parts of Schinus molle L. and the influence of the process on the composition of the extracts. Experiments were performed in a pilot-scale extractor with a capacity of 1 L at pressures of 9, 10, 12, 15 and 20 MPa at 323.15 K. The volatile compounds were obtained by CO2 supercritical extraction with moderate pressure (9 MPa, whereas the non-volatile compounds were extracted at higher pressure (12 to 20 MPa. The analysis of the essential oil was carried out by GC-MS and the main compounds identified were sabinene, limonene, D-germacrene, bicyclogermacrene, and spathulenol. For the non-volatile extracts, the total phenolic content was determined by the Folin-Ciocalteau method. Moreover, one of the goals of this study was to compare the experimental data with the simulated yields predicted by a mathematical model based on mass transfer. The model used requires three adjustable parameters to predict the experimental extraction yield curves.

  19. Synthesis and Characterization of Quaternary Metal Chalcogenide Aerogels for Gas Separation and Volatile Hydrocarbon Adsorption

    KAUST Repository

    Edhaim, Fatimah A.

    2017-11-01

    In this dissertation, the metathesis route of metal chalcogenide aerogel synthesis was expanded by conducting systematic studies between polysulfide building blocks and the 1st-row transition metal linkers. Resulting materials were screened as sorbents for selective gas separation and volatile organic compounds adsorption. They showed preferential adsorption of polarizable gases (CO2) and organic compounds (toluene). Ion exchange and heavy metal remediation properties have also been demonstrated. The effect of the presence of different counter-ion within chalcogel frameworks on the adsorption capacity of the chalcogels was studied on AFe3Zn3S17 (A= K, Na, and Rb) chalcogels. The highest adsorption capacity toward hydrocarbons and gases was observed on Rb based chalcogels. Adopting a new building block [BiTe3]3- with the 1st-row transition metal ions results in the formation of three high BET surface area chalcogels, KCrBiTe3, KZnBiTe3, and KFeBiTe3. The resulting chalcogels showed preferential adsorption of toluene vapor, and remarkable selectivity of CO2, indicating the potential future use of chalcogels in adsorption-based gas or hydrocarbon separation processes. The synthesis and characterization of the rare earth chalcogels NaYSnS4, NaGdSnS4, and NaTbSnS4 are also reported. Rare earth metal ions react with the thiostannate clusters in formamide solution forming extended polymeric networks by gelation. Obtained chalcogels have high BET surface areas, and showed notable adsorption capacity toward CO2 and toluene vapor. These chalcogels have also been engaged in the absorption of different organic molecules. The results reveal the ability of the chalcogels to distinguish among organic molecules on their electronic structures; hence, they could be used as sensors. Furthermore, the synthesis of metal chalcogenide aerogels Co0.5Sb0.33MoS4 and Co0.5Y0.33MoS4 by the sol-gel method is reported. In this system, the building blocks [MoS4]2- chelated with Co2+ and (Sb3

  20. Assessment of Volatile Chemical Composition of the Essential Oil of Jatropha ribifolia (Pohl Baill by HS-SPME-GC-MS Using Different Fibers

    Directory of Open Access Journals (Sweden)

    Celia Eliane de Lara da Silva

    2013-01-01

    Full Text Available The chemical composition of essential oil and volatile obtained from the roots of Jatropha ribifolia (Pohl Baill was performed in this work. The Clevenger extractor was utilized in hydrodistillation of oil and chemical composition determined by gas chromatography coupled with mass spectrometry detector (GC-MS. The identification of compounds was confirmed by retention index (Kovats index obtained from a series of straight chain alkanes (C7–C30 and by comparison with NIST and ADAMS library. A total of 61 compounds were identified in essential oil by GC-MS. The extraction of volatile was performed also by the use of the solid phase microextraction (SPME with four different fibers. The essential oil extraction was extremely rapid (15 s to avoid saturation of the fiber and the MS detector. The majority of the composition of essential oil is the terpenes: β-pinene (major compound 9.16%, β-vatirene (8.34%, α-gurjunene (6.98%, α-pinene (6.35%, camphene (4.34%, tricyclene (3.79% and dehydro aromadendrene (3.52% it and aldehydes and alcohols. Through the SPME it was possible to determine the nine volatile compounds not identified in oil 2,3,4-trimethyl-2-cyclopenten-1-one, α-phellandrene, 3-carene, trans-p-mentha-2,8-dienol, pinocamphone, D-verbenon, 1,3,3-trimethyl-2-(2-methyl-cyclopropyl-cyclohexene, 2,4-diisocyanato-1-methylbenzene, and (6-hydroxymethyl-2,3-dimethylehenyl methanol.

  1. Time-varying volatility in Malaysian stock exchange: An empirical study using multiple-volatility-shift fractionally integrated model

    Science.gov (United States)

    Cheong, Chin Wen

    2008-02-01

    This article investigated the influences of structural breaks on the fractionally integrated time-varying volatility model in the Malaysian stock markets which included the Kuala Lumpur composite index and four major sectoral indices. A fractionally integrated time-varying volatility model combined with sudden changes is developed to study the possibility of structural change in the empirical data sets. Our empirical results showed substantial reduction in fractional differencing parameters after the inclusion of structural change during the Asian financial and currency crises. Moreover, the fractionally integrated model with sudden change in volatility performed better in the estimation and specification evaluations.

  2. Volatile composition of Merlot red wine and its contribution to the aroma: optimization and validation of analytical method.

    Science.gov (United States)

    Arcari, Stefany Grützmann; Caliari, Vinicius; Sganzerla, Marla; Godoy, Helena Teixeira

    2017-11-01

    A methodology for the determination of volatile compounds in red wine using headspace solid phase microextraction (HS-SPME) combined with gas chromatography-ion trap/ mass spectrometry (GC-IT/MS) and flame ionization detector (GC -FID) was developed, validated and applied to a sample of Brazilian red wine. The optimization strategy was conducted using the Plackett-Burman design for variable selection and central composite rotational design (CCRD). The response surface methodology showed that the performance of the extraction of the volatile compounds using divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber is improved with no sample dilution, the addition of 30% NaCl, applying an extraction temperature of 56°C and extraction time of 55min. The qualitative method allowed the extraction and identification of 60 volatile compounds in the sample studied, notably the classes of esters, alcohols, and fatty acids. Furthermore, the method was successfully validated for the quantification of 55 volatile compounds of importance in wines and applied to twelve samples of Merlot red wine from South of Brazil. The calculation of the odor activity value (OAV) showed the most important components of the samples aroma. Ethyl isovalerate, ethyl hexanoate, 1-hexanol, octanoic acid and ethyl cinnamate had the greatest contribution to the aroma of the wines analyzed, which is predominantly fruity with the presence of herbal and fatty odors. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Comparison of passive and standard dosing of polycyclic aromatic hydrocarbons to the marine algae Phaeodactylum tricornutum

    DEFF Research Database (Denmark)

    Witt, G.; Niehus, N. C.; Konopka, K.

    2015-01-01

    Testing hydrophobic organic compounds (HOCs), like polycyclic aromatic hydrocarbons (PAHs), in aquatic toxicity tests is difficult due to compound losses through volatilization, sorption to the test vessel and culture medium constituents. This results in poorly defined exposure, the bioavailable...

  4. Volatilization of polycyclic aromatic hydrocarbons from coal-tar-sealed pavement

    Science.gov (United States)

    Van Metre, Peter C.; Majewski, Michael S.; Mahler, Barbara J.; Foreman, William T.; Braun, Christopher L.; Wilson, Jennifer T.; Burbank, Teresa L.

    2012-01-01

    Coal-tar-based pavement sealants, a major source of PAHs to urban water bodies, are a potential source of volatile PAHs to the atmosphere. An initial assessment of volatilization of PAHs from coal-tar-sealed pavement is presented here in which we measured summertime gas-phase PAH concentrations 0.03 m and 1.28 m above the pavement surface of seven sealed (six with coal-tar-based sealant and one with asphalt-based sealant) and three unsealed (two asphalt and one concrete) parking lots in central Texas. PAHs also were measured in parking lot dust. The geometric mean concentration of the sum of eight frequently detected PAHs (ΣPAH8) in the 0.03-m samples above sealed lots (1320 ng m-3) during the hottest part of the day was 20 times greater than that above unsealed lots (66.5 ng m-3). The geometric mean concentration in the 1.28-m samples above sealed lots (138 ng m-3) was five times greater than above unsealed lots (26.0 ng m-3). Estimated PAH flux from the sealed lots was 60 times greater than that from unsealed lots (geometric means of 88 and 1.4 μg m-2 h-1, respectively). Although the data set presented here is small, the much higher estimated fluxes from sealed pavement than from unsealed pavement indicate that coal-tar-based sealants are emitting PAHs to urban air at high rates compared to other paved surfaces.

  5. Revealing the properties of oils from their dissolved hydrocarbon compounds in water with an integrated sensor array system.

    Science.gov (United States)

    Qi, Xiubin; Crooke, Emma; Ross, Andrew; Bastow, Trevor P; Stalvies, Charlotte

    2011-09-21

    This paper presents a system and method developed to identify a source oil's characteristic properties by testing the oil's dissolved components in water. Through close examination of the oil dissolution process in water, we hypothesise that when oil is in contact with water, the resulting oil-water extract, a complex hydrocarbon mixture, carries the signature property information of the parent oil. If the dominating differences in compositions between such extracts of different oils can be identified, this information could guide the selection of various sensors, capable of capturing such chemical variations. When used as an array, such a sensor system can be used to determine parent oil information from the oil-water extract. To test this hypothesis, 22 oils' water extracts were prepared and selected dominant hydrocarbons analyzed with Gas Chromatography-Mass Spectrometry (GC-MS); the subsequent Principal Component Analysis (PCA) indicates that the major difference between the extract solutions is the relative concentration between the volatile mono-aromatics and fluorescent polyaromatics. An integrated sensor array system that is composed of 3 volatile hydrocarbon sensors and 2 polyaromatic hydrocarbon sensors was built accordingly to capture the major and subtle differences of these extracts. It was tested by exposure to a total of 110 water extract solutions diluted from the 22 extracts. The sensor response data collected from the testing were processed with two multivariate analysis tools to reveal information retained in the response patterns of the arrayed sensors: by conducting PCA, we were able to demonstrate the ability to qualitatively identify and distinguish different oil samples from their sensor array response patterns. When a supervised PCA, Linear Discriminate Analysis (LDA), was applied, even quantitative classification can be achieved: the multivariate model generated from the LDA achieved 89.7% of successful classification of the type of the

  6. Volatility measurement of atmospheric submicron aerosols in an urban atmosphere in southern China

    Directory of Open Access Journals (Sweden)

    L.-M. Cao

    2018-02-01

    Full Text Available Aerosol pollution has been a very serious environmental problem in China for many years. The volatility of aerosols can affect the distribution of compounds in the gas and aerosol phases, the atmospheric fates of the corresponding components, and the measurement of the concentration of aerosols. Compared to the characterization of chemical composition, few studies have focused on the volatility of aerosols in China. In this study, a thermodenuder aerosol mass spectrometer (TD-AMS system was deployed to study the volatility of non-refractory submicron particulate matter (PM1 species during winter in Shenzhen. To our knowledge, this paper is the first report of the volatilities of aerosol chemical components based on a TD-AMS system in China. The average PM1 mass concentration during the experiment was 42.7±20.1 µg m−3, with organic aerosol (OA being the most abundant component (43.2 % of the total mass. The volatility of chemical species measured by the AMS varied, with nitrate showing the highest volatility, with a mass fraction remaining (MFR of 0.57 at 50 °C. Organics showed semi-volatile characteristics (the MFR was 0.88 at 50 °C, and the volatility had a relatively linear correlation with the TD temperature (from the ambient temperature to 200 °C, with an evaporation rate of 0.45 % °C−1. Five subtypes of OA were resolved from total OA using positive matrix factorization (PMF for data obtained under both ambient temperature and high temperatures through the TD, including a hydrocarbon-like OA (HOA, accounting for 13.5 %, a cooking OA (COA, 20.6 %, a biomass-burning OA (BBOA, 8.9 %, and two oxygenated OAs (OOAs: a less-oxidized OOA (LO-OOA, 39.1 % and a more-oxidized OOA (MO-OOA, 17.9 %. Different OA factors presented different volatilities, and the volatility sequence of the OA factors at 50 °C was HOA (MFR of 0.56  >  LO-OOA (0.70  >  COA (0.85  ≈  BBOA (0.87

  7. Volatile element trends in gas-rich meteorites

    Energy Technology Data Exchange (ETDEWEB)

    Bart, G; Lipschutz, M E [Purdue Univ., Lafayette, IN (USA). Dept. of Chemistry

    1979-09-01

    Study of 10 volatile elements (and non-volatile Co) in co-existing light and dark portions of 5 gas-rich chondrites indicates patterns of distinct but non-uniform enrichment of volatile elements. Only Cs is enriched in all samples; Bi and Tl enrichments covary. The observed enrichments are inconsistent with prior suggestions of admixture of C1 or C2 chondritic matter, whether pristine or partly devolatilized, but suggest that both light and dark portions of each chondrite represents a compositionally more extended sampling of parental nebular material than hitherto known.

  8. Detection of radiation-induced hydrocarbons in Camembert irradiated before and after the maturing process-comparison of florisil column chromatography and on-line coupled liquid chromatography-gas chromatography

    International Nuclear Information System (INIS)

    Schulzki, G.; Spiegelberg, A.; Bögl, K.W.; Schreiber, G.A.

    1995-01-01

    The influence of the maturing process on the detection of radiation-induced volatile hydrocarbons in the fat of Camembert has been investigated. Two analytical methods for separation of the hydrocarbon fraction from the lipid were applied: Florisil column chromatography with subsequent gas chromatographic-mass spectrometric (GC-MS) determination as well as on-line coupled liquid chromatography-GC-MS. The maturing process had no influence on the detection of radiation-induced volatiles. Comparable results were achieved with both analytical methods. However, preference is given to the more effective on-line coupled LC-GC method

  9. Preferential adsorption of volatile hydrocarbons on high surface area chalcogels KMBiTe 3 (M = Cr, Zn, Fe)

    KAUST Repository

    Edhaim, Fatimah

    2017-12-21

    Three chalcogels KCrBiTe3, KZnBiTe3, and KFeBiTe3 were synthesized by the sol–gel metathesis route. K+ and the transition metal cations Cr2+, Zn2+ or Fe2+ connect [BiTe3]3− anions to form amorphous black compounds. Supercritical drying of the black gels produced porous materials with BET surface areas of 230 m2/g (KCrBiTe3), 450 m2/g (KZnBiTe3) and 514 m2/g (KFeBiTe3). The adsorption properties of the resulting chalcogenide aerogels or chalcogels have been studied using volatile organic hydrocarbons (VOCs) and gases as adsorptives. The results show preferential adsorption of toluene vapor over cyclohexane vapor. The adsorption capacity toward toluene is 5.02 mmol/g for KCrBiTe3, 5.58 mmol/g for KZnBiTe3 and 7.89 mmol/g for KFeBiTe3. Preferential adsorption of CO2 over CH4 or H2 was observed for the chalcogels: KCrBiTe3 (CO2/H2: 175, CO2/CH4: 50), KZnBiTe3 (CO2/H2: 180 and CO2/CH4: 60) and KFeBiTe3 (CO2/H2: 225 and CO2/CH4: 65).

  10. THE DETERMINATION OF VOLATILE COMPOSITION OF SOLID FUELS BY CHROMATOGRAPHY

    OpenAIRE

    BICA Marin; SOFRONIE Sorin; CERNAIANU Corina Dana

    2014-01-01

    The volatile materials released during the heating of solid fuels ignite at relatively low temperatures releasing heat function of their quantity and quality. This heat raises the temperature of the solid residue creating the conditions for his ignition and burning. In the case of burning of the pulverized coal the phenomenon of production, ignition and burning of volatile materials are studied in different articles.

  11. VOLATILE COMPOUNDS IDENTIFIED IN BARBADOS CHERRY ‘BRS-366 JABURÚ’

    Directory of Open Access Journals (Sweden)

    Y. M. Garcia

    2016-07-01

    Full Text Available In foods, the flavor and aroma are very important attributes, thus the main objective of this study was to identify the volatile compounds (VC of the "BRS-366 Jaburú" acerola variety, for which we used the solid phase microextraction method (SPE. The separation and identification of volatile compounds was made using gas chromatography-mass spectrometry (GC-MS. Three fibers were evaluated, Polydimethylsiloxane / Divinylbenzene (PDMS / DVB, 65 micrometres Divinylbenzene / Carboxen / Polydimethylsiloxane (DVB / CAR / PDMS 50/30 m and polyacrylate (PA 85 uM to compare the extraction of its components. Thirty-three volatile compounds were identified and classified into eight chemical classes: carboxylic acids, alcohols, aldehydes, ketones, esters, hydrocarbons, phenylpropanoids and terpenoids. The peak areas of each of the extracted compounds were expressed as percentages to indicate the relative concentration of each, of which ethyl acetate is distinguished by being responsible for the fruity aroma notes. Thus, the fiber PDMS / DVB was the best as it enabled to extract a greater amount of volatile compounds

  12. Effect of γ-irradiation on the volatile compounds of medicinal herb, Paeoniae Radix

    International Nuclear Information System (INIS)

    Shim, Sung-Lye; Hwang, In-Min; Ryu, Keun-Young; Jung, Min-Seok; Seo, Hye-young; Kim, Hee-Yeon; Song, Hyun-Pa; Kim, Jae-Hun; Lee, Ju-Woon; Byun, Myung-Woo; Kwon, Joong-Ho; Kim, Kyong-Su

    2009-01-01

    A study was carried out to find the effect of γ-irradiation on contents of volatile compounds from medicinal herb, Paeoniae Radix (Paenia albiflora Pallas var. trichocarpa Bunge). The volatile compounds of control, 1, 3, 5 and 10 kGy irradiated samples were extracted by simultaneous steam distillation and extraction (SDE) method and analyzed by gas chromatograph-mass spectrometer. The major volatile compounds were paeonol, (E)-carveol, (E,E)-2,4-octadienal, methyl salicylate, myrtanol and eugenol acetate. Volatile compounds belonging to chemical classes of acids, alcohols, aldehydes, esters, hydrocarbons and miscellaneous were identified in all experimental samples. The types of volatile compounds in irradiated samples were similar to those of non-irradiated sample and the concentrations of these compounds differed between treatments. 1,3-Bis (1,1-dimethylethyl)-benzene was identified by using the selected ion monitoring (GC/MS-SIM) mode. The concentration of this compound increased with the increase of irradiation dose level. These results suggest that it could be used as the base data for the effect of γ-irradiation on medicinal herb.

  13. Effect of {gamma}-irradiation on the volatile compounds of medicinal herb, Paeoniae Radix

    Energy Technology Data Exchange (ETDEWEB)

    Shim, Sung-Lye; Hwang, In-Min; Ryu, Keun-Young; Jung, Min-Seok [Department of Food and Nutrition, Chosun University (Korea, Republic of); Seo, Hye-young [Korea Food Research Institute (Korea, Republic of); Kim, Hee-Yeon [Korea Food and Drug Administration (Korea, Republic of); Song, Hyun-Pa; Kim, Jae-Hun; Lee, Ju-Woon; Byun, Myung-Woo [Advanced Radiation Technology Institute, KAERI, Jeongeup 580-185 (Korea, Republic of); Kwon, Joong-Ho [Department of Food Science and Technology, Kyungpook National University (Korea, Republic of); Kim, Kyong-Su [Korea Food Research Institute (Korea, Republic of)], E-mail: kskim@chosun.ac.kr

    2009-07-15

    A study was carried out to find the effect of {gamma}-irradiation on contents of volatile compounds from medicinal herb, Paeoniae Radix (Paenia albiflora Pallas var. trichocarpa Bunge). The volatile compounds of control, 1, 3, 5 and 10 kGy irradiated samples were extracted by simultaneous steam distillation and extraction (SDE) method and analyzed by gas chromatograph-mass spectrometer. The major volatile compounds were paeonol, (E)-carveol, (E,E)-2,4-octadienal, methyl salicylate, myrtanol and eugenol acetate. Volatile compounds belonging to chemical classes of acids, alcohols, aldehydes, esters, hydrocarbons and miscellaneous were identified in all experimental samples. The types of volatile compounds in irradiated samples were similar to those of non-irradiated sample and the concentrations of these compounds differed between treatments. 1,3-Bis (1,1-dimethylethyl)-benzene was identified by using the selected ion monitoring (GC/MS-SIM) mode. The concentration of this compound increased with the increase of irradiation dose level. These results suggest that it could be used as the base data for the effect of {gamma}-irradiation on medicinal herb.

  14. FATE OF PAH COMPOUNDS IN TWO SOIL TYPES: INFLUENCE OF VOLATILIZATION, ABIOTIC LOSS, AND BIOLOGICAL ACTIVITY

    Science.gov (United States)

    The fate of 14 polycyclic aromatic hydrocarbon (PAH) compounds was evaluated with regard to interphase transfer potential and mechanisms of treatment in soil under unsaturated conditions. Volatilization and abiotic and biotic fate of the PAHs were determined using two soils not p...

  15. Observability of market daily volatility

    Science.gov (United States)

    Petroni, Filippo; Serva, Maurizio

    2016-02-01

    We study the price dynamics of 65 stocks from the Dow Jones Composite Average from 1973 to 2014. We show that it is possible to define a Daily Market Volatility σ(t) which is directly observable from data. This quantity is usually indirectly defined by r(t) = σ(t) ω(t) where the r(t) are the daily returns of the market index and the ω(t) are i.i.d. random variables with vanishing average and unitary variance. The relation r(t) = σ(t) ω(t) alone is unable to give an operative definition of the index volatility, which remains unobservable. On the contrary, we show that using the whole information available in the market, the index volatility can be operatively defined and detected.

  16. Silicon isotopes in angrites and volatile loss in planetesimals

    OpenAIRE

    Pringle, Emily A.; Moynier, Frédéric; Savage, Paul S.; Badro, James; Barrat, Jean-Alix

    2014-01-01

    Understanding volatile elements in the early solar system is a key step toward understanding the processes of planetary formation and the composition of Earth, but the origin of volatiles on Earth is not well understood. In this article, we present measurements of silicon isotope ratios in angrites, a class of meteorites dating from the first few million years after condensation of solids from the solar nebula. We show that the silicon isotope composition of angrites is consistent with a depl...

  17. To the question the unity of composition of fluids of heterogeneous geological objects.

    Science.gov (United States)

    Galant, Yuri

    2017-04-01

    Creation of Unit Theory Oil Generation based on a number of the provisions, one of which is the unity of the hydrocarbon composition in various geological objects. Studies conducted in various geological conditions and tectonic - magmatic environment. In studying the hydrocarbon composition of various geological objects, untraditional for petroleum geology (igneous rocks, metamorphic rocks, mineral deposits, etc.) progressively manifested that hydrocarbons are also distributed and have the following features. Studies have shown: 1. The composition of the hydrocarbon components presented by, light hydrocarbons, heavy hydrocarbons up to including hexane, normal forms, isoforms, saturated and unsaturated hydrocarbons. 2. Hydrocarbon composition and the ratio of methane to heavy hydrocarbons corresponds to the composition of gases gas fields. 3. The composition and the ratio of hydrocarbons do not depend on genetic types of heterogeneous geological objects. 4. Gas saturation meets the prevailing structure of rocks - pores or fractures. The foregoing allows us to speak of a single source of generating and delivering hydrocarbons in the Earth's Crust, regardless of the geological situation. I.e. the presence of hydrocarbons in the Earth's Crust is UNITED! 5. From a practical point of view - virtually unconventional for hydrocarbons rock can serve as unconventional hydrocarbon resources.

  18. Volatile element loss during planetary magma ocean phases

    Science.gov (United States)

    Dhaliwal, Jasmeet K.; Day, James M. D.; Moynier, Frédéric

    2018-01-01

    Moderately volatile elements (MVE) are key tracers of volatile depletion in planetary bodies. Zinc is an especially useful MVE because of its generally elevated abundances in planetary basalts, relative to other MVE, and limited evidence for mass-dependent isotopic fractionation under high-temperature igneous processes. Compared with terrestrial basalts, which have δ66Zn values (per mille deviation of the 66Zn/64Zn ratio from the JMC-Lyon standard) similar to some chondrite meteorites (∼+0.3‰), lunar mare basalts yield a mean δ66Zn value of +1.4 ± 0.5‰ (2 st. dev.). Furthermore, mare basalts have average Zn concentrations ∼50 times lower than in typical terrestrial basaltic rocks. Late-stage lunar magmatic products, including ferroan anorthosite, Mg- and Alkali-suite rocks have even higher δ66Zn values (+3 to +6‰). Differences in Zn abundance and isotopic compositions between lunar and terrestrial rocks have previously been interpreted to reflect evaporative loss of Zn, either during the Earth-Moon forming Giant Impact, or in a lunar magma ocean (LMO) phase. To explore the mechanisms and processes under which volatile element loss may have occurred during a LMO phase, we developed models of Zn isotopic fractionation that are generally applicable to planetary magma oceans. Our objective was to identify conditions that would yield a δ66Zn signature of ∼+1.4‰ within the lunar mantle. For the sake of simplicity, we neglect possible Zn isotopic fractionation during the Giant Impact, and assumed a starting composition equal to the composition of the present-day terrestrial mantle, assuming both the Earth and Moon had zinc 'consanguinity' following their formation. We developed two models: the first simulates evaporative fractionation of Zn only prior to LMO mixing and crystallization; the second simulates continued evaporative fractionation of Zn that persists until ∼75% LMO crystallization. The first model yields a relatively homogenous bulk solid

  19. Comets, volcanism, the salt-rich regolith, and cycling of volatiles on Mars

    International Nuclear Information System (INIS)

    Clark, B.C.

    1987-01-01

    The composition of the Martian surface and its evolution are examined, reviewing the results of recent theoretical models and composition estimates based on Viking-lander analyses. The data are compiled in tables and characterized in detail, and a high degree of variation among the predictions is noted. The discussion centers on the possible roles of comets (as sources of volatiles), the salt-rich regolith (as an important water sink), and volcanic activity (interfering with volatile-recycling processes and eventually producing a volatile-depleted surface layer). 45 references

  20. Volatilization of polycyclic aromatic hydrocarbons from coal-tar-sealed pavement.

    Science.gov (United States)

    Van Metre, Peter C; Majewski, Michael S; Mahler, Barbara J; Foreman, William T; Braun, Christopher L; Wilson, Jennifer T; Burbank, Teresa L

    2012-06-01

    Coal-tar-based pavement sealants, a major source of PAHs to urban water bodies, are a potential source of volatile PAHs to the atmosphere. An initial assessment of volatilization of PAHs from coal-tar-sealed pavement is presented here in which we measured summertime gas-phase PAH concentrations 0.03 m and 1.28 m above the pavement surface of seven sealed (six with coal-tar-based sealant and one with asphalt-based sealant) and three unsealed (two asphalt and one concrete) parking lots in central Texas. PAHs also were measured in parking lot dust. The geometric mean concentration of the sum of eight frequently detected PAHs (ΣPAH(8)) in the 0.03-m samples above sealed lots (1320 ng m(-3)) during the hottest part of the day was 20 times greater than that above unsealed lots (66.5 ng m(-3)). The geometric mean concentration in the 1.28-m samples above sealed lots (138 ng m(-3)) was five times greater than above unsealed lots (26.0 ng m(-3)). Estimated PAH flux from the sealed lots was 60 times greater than that from unsealed lots (geometric means of 88 and 1.4 μg m(-2) h(-1), respectively). Although the data set presented here is small, the much higher estimated fluxes from sealed pavement than from unsealed pavement indicate that coal-tar-based sealants are emitting PAHs to urban air at high rates compared to other paved surfaces. Published by Elsevier Ltd.

  1. Volatile composition and sensory profile of Cantharellus cibarius Fr. as affected by drying method.

    Science.gov (United States)

    Politowicz, Joanna; Lech, Krzysztof; Sánchez-Rodríguez, Lucía; Szumny, Antoni; Carbonell-Barrachina, Ángel A

    2017-12-01

    In this work, the influence of different drying methods on the aroma composition and sensory quality of chanterelle mushrooms (Cantharellus cibarius Fr.) was evaluated. The drying methods tested were convective drying (CD), freeze drying (FD), vacuum microwave drying (VMD) and a combination of convective pre-drying and vacuum microwave finish drying (CPD-VMFD). Analyses of fresh and dried chanterelle samples by HS-SPME and GC/MS and GC-FID showed the presence of 39 volatile compounds at different concentrations. The most abundant compounds in fresh chanterelle were 1-hexanol (33.4 μg per 100 g dry basis (db)), 1-octen-3-ol (80.2 μg per 100 g db) and 2-octen-1-ol (19.3 μg per 100 g db). The results showed that fresh and dried chanterelle contained very low levels of aroma compounds; however, the highest contents of volatile compounds were found in samples after (i) CD at 80 °C (129 μg per 100 g db), (ii) CPD-VMFD at 70 °C-480/240 W (136 μg per 100 g db) and (iii) CPD-VMFD at 80 °C-480/240 W (136 μg per 100 g db). The best dehydration methods, which resulted in high contents of volatile compounds and appropriate sensory quality, according to descriptive sensory analysis and PCA tools, were CD at 70 and 80 °C. Besides, these methods led to spongy dried mushrooms with high intensities of fresh, mushroom ID, with proper color and without intense shrinkage. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  2. Hydrocarbons in the suspended matter and the bottom sediments in different regions of the Black Sea Russian sector

    Directory of Open Access Journals (Sweden)

    I. A. Nemirovskaya

    2017-08-01

    Full Text Available Content and composition of hydrocarbons (mainly the aliphatic ones in the suspended matter and the bottom sediments in the Gelendzhik Bay, the Big Sochi water area, the Feodosiya Bay and the Black Sea central part are defined and compared with the total organic carbon and chlorophyll a contents. It is shown that the aliphatic hydrocarbon concentrations exceeding the background ones are found only in the coastal zone. Advancing to the pelagic zone is accompanied by sharp decrease of their concentrations. Petroleum and pyrogenic hydrocarbons are mainly manifested in the polycyclic aromatic hydrocarbons composition. Influence of construction of the Olympic facilities upon distribution of hydrocarbons in the Big Sochi water area was of short duration, and already by 2015 the aliphatic hydrocarbons concentration decreased, on the average, up to 24 µg/l in the surface waters, and up to 18 µg/g – in the bottom sediments. Accumulation of hydrocarbons took place in bottom sediments, where their concentrations exceeded the background ones in terms of dry weight. In the Gelendzhik Bay, their content reached 252 μg/g, and in the composition of organic carbon (Corg > 1 %, which may indicate the contamination of sediments with oil products. In the Feodosiya Bay their part in the composition of Corg did not exceed 0.73 % and was 0.35 % on average. Natural alkanes dominated in the composition of aliphatic hydrocarbons. The bottom sediments are characterized by the predominance of odd high-molecular terrigenous alkanes. The content of polycyclic aromatic hydrocarbons in the studied sediments was rather low: up to 31 ng/g in the Gelendzhik Bay, up to 348 ng/g in the Feodosiya Bay. These concentrations according to the EPA classification are considered background, or minor petroleum hydrocarbons increase the level of aliphatic hydrocarbons in water and sediments, thus creating a modern hydrocarbon background.

  3. Constraining the volatile budget of the lunar interior

    Science.gov (United States)

    Potts, N. J.; Bromiley, G. D.

    2017-12-01

    Measurements of volatiles (F, Cl, S, H2O) in a range of lunar samples confirm the presence of volatile material in lunar magmas. It remains unknown, however, where this volatile material is stored and when it was delivered to the Moon. On Earth, point defects within mantle olivine, and its high-pressure polymorphs, are thought to be the largest reservoir of volatile material. However, as volatiles have been cycled into and out of the Earth's mantle throughout geological time, via subduction and volcanism, this masks any original volatile signatures. As the Moon has no plate tectonics, it is expected that any volatile material present in the deep lunar interior would have been inherited during accretion and differentiation, providing insight into the delivery of volatiles to the early Earth-Moon system. Our aim was, therefore, to test the volatile storage capacity of the deep lunar mantle and determine mineral/melt partitioning for key volatiles. Experiments were performed in a primitive lunar mantle composition and run at relevant T, P, and at fO2 below the IW buffer. Experiments replicated the initial stages of LMO solidification with either olivine + melt, olivine + pyroxene + melt, or pyroxene + melt as the only phases present. Mineral-melt partition coefficients (Dx) derived for volatile material (F, Cl, S, H2O) vary significantly compared to those derived for terrestrial conditions. An order of magnitude more H2O was found to partition into lunar olivine compared to the terrestrial upper mantle. DF derived for lunar olivine are comparable to the highest terrestrial derived values whilst no Cl was found to partition into lunar olivine under these conditions. Furthermore, an inverse trend between DF and DOH hints towards coupled-substitution mechanisms between H and F under low-fO2/lunar bulk composition. These results suggest that if volatile material was present in the LMO a significant proportion could be partitioned into the lower lunar mantle. The

  4. Highly sensitive analysis of polycyclic aromatic hydrocarbons in environmental water with porous cellulose/zeolitic imidazolate framework-8 composite microspheres as a novel adsorbent coupled with high-performance liquid chromatography.

    Science.gov (United States)

    Liang, Xiaotong; Liu, Shengquan; Zhu, Rong; Xiao, Lixia; Yao, Shouzhuo

    2016-07-01

    In this work, novel cellulose/zeolitic imidazolate frameworks-8 composite microspheres have been successfully fabricated and utilized as sorbent for environmental polycyclic aromatic hydrocarbons efficient extraction and sensitive analysis. The composite microspheres were synthesized through the in situ hydrothermal growth of zeolitic imidazolate frameworks-8 on cellulose matrix, and exhibited favorable hierarchical structure with chemical composition as assumed through scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction patterns, and Brunauer-Emmett-Teller surface areas characterization. A robust and highly efficient method was then successfully developed with as-prepared composite microspheres as novel solid-phase extraction sorbent with optimum extraction conditions, such as sorbent amount, sample volume, extraction time, desorption conditions, volume of organic modifier, and ionic strength. The method exhibited high sensitivity with low limit of detection down to 0.1-1.0 ng/L and satisfactory linearity with correlation coefficients ranging from 0.9988 to 0.9999, as well as good recoveries of 66.7-121.2% with relative standard deviations less than 10% for environmental polycyclic aromatic hydrocarbons analysis. Thus, our method was convenient and efficient for polycyclic aromatic hydrocarbons extraction and detection, potential for future environmental water samples analysis. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. The automated sample preparation system MixMaster for investigation of volatile organic compounds with mid-infrared evanescent wave spectroscopy.

    Science.gov (United States)

    Vogt, F; Karlowatz, M; Jakusch, M; Mizaikoff, B

    2003-04-01

    For efficient development assessment, and calibration of new chemical analyzers a large number of independently prepared samples of target analytes is necessary. Whereas mixing units for gas analysis are readily available, there is a lack of instrumentation for accurate preparation of liquid samples containing volatile organic compounds (VOCs). Manual preparation of liquid samples containing VOCs at trace concentration levels is a particularly challenging and time consuming task. Furthermore, regularly scheduled calibration of sensors and analyzer systems demands for computer controlled automated sample preparation systems. In this paper we present a novel liquid mixing device enabling extensive measurement series with focus on volatile organic compounds, facilitating analysis of water polluted by traces of volatile hydrocarbons. After discussing the mixing system and control software, first results obtained by coupling with an FT-IR spectrometer are reported. Properties of the mixing system are assessed by mid-infrared attenuated total reflection (ATR) spectroscopy of methanol-acetone mixtures and by investigation of multicomponent samples containing volatile hydrocarbons such as 1,2,4-trichlorobenzene and tetrachloroethylene. Obtained ATR spectra are evaluated by principal component regression (PCR) algorithms. It is demonstrated that the presented sample mixing device provides reliable multicomponent mixtures with sufficient accuracy and reproducibility at trace concentration levels.

  6. Gas Chromatographic-Ion Trap Mass Spectrometric Analysis of Volatile Organic Compounds by Ion-Molecule Reactions Using the Electron-Deficient Reagent Ion CCl{3/+}

    Science.gov (United States)

    Wang, Cheng-Zhong; Su, Yue; Wang, Hao-Yang; Guo, Yin-Long

    2011-10-01

    When using tetrachloromethane as the reagent gas in gas chromatography-ion trap mass spectrometry equipped with hybrid ionization source, the cation CCl{3/+} was generated in high abundance and further gas-phase experiments showed that such an electron-deficient reagent ion CCl{3/+} could undergo interesting ion-molecule reactions with various volatile organic compounds, which not only present some informative gas-phase reactions, but also facilitate qualitative analysis of diverse volatile compounds by providing unique mass spectral data that are characteristic of particular chemical structures. The ion-molecule reactions of the reagent ion CCl{3/+} with different types of compounds were studied, and results showed that such reactions could give rise to structurally diagnostic ions, such as [M + CCl3 - HCl]+ for aromatic hydrocarbons, [M - OH]+ for saturated cyclic ether, ketone, and alcoholic compounds, [M - H]+ ion for monoterpenes, M·+ for sesquiterpenes, [M - CH3CO]+ for esters, as well as the further fragment ions. The mechanisms of ion-molecule reactions of aromatic hydrocarbons, aliphatic ketones and alcoholic compounds with the reagent ion CCl{3/+} were investigated and proposed according to the information provided by MS/MS experiments and theoretical calculations. Then, this method was applied to study volatile organic compounds in Dendranthema indicum var. aromaticum and 20 compounds, including monoterpenes and their oxygen-containing derivatives, aromatic hydrocarbon and sesquiterpenes were identified using such ion-molecule reactions. This study offers a perspective and an alternative tool for the analysis and identification of various volatile compounds.

  7. Volatile compounds and phenolic composition of virgin olive oil: optimization of temperature and time of exposure of olive pastes to air contact during the mechanical extraction process.

    Science.gov (United States)

    Servili, Maurizio; Selvaggini, Roberto; Taticchi, Agnese; Esposto, Sonia; Montedoro, GianFrancesco

    2003-12-31

    The operative conditions of malaxation such as temperature and time of exposure of olive pastes to air contact (TEOPAC) affect volatile and phenolic composition of virgin olive oil (VOO) and, as a consequence, its sensory and healthy qualities. In this paper, optimal temperature and TEOPAC during malaxation were studied, in lab scale, in two Italian cultivars using phenolic compounds, volatile composition, and sensory analysis of VOO as markers. The optimal temperature and TEOPAC, selected by response surface modeling,were cultivar-dependent being 30 min of TEOPAC at the lowest temperature investigated (22 degrees C) and 0 min of TEOPAC at 26 degrees C for Frantoio and Moraiolo cultivars, respectively.

  8. Effect of γ-irradiation on bioactivity, fatty acid compositions and volatile compounds of clary sage seed (Salvia sclarea L.).

    Science.gov (United States)

    Yalcin, Hasan; Ozturk, Ismet; Tulukcu, Eray; Sagdic, Osman

    2011-09-01

    Clary sage seeds (Salvia sclarea L.) were obtained from plants cultivated, and 2.5, 4.0, 5.5, and 7.0 kGy doses of γ-irradiation were applied to the clary sage seeds. They were then analyzed for their protein, ash, oil and dry matter contents, and fatty acid composition. Additionally, the total phenolic contents, antiradical, antioxidant activities, and volatile compounds of the clary sage seed extract were determined. There was no significant difference in protein content. However, the moisture, oil, and ash contents of the samples were affected by irradiation. While the 7 kGy dose had a positive effect on the total phenolic content and antiradical activity of the sage seed extract, all doses have negative effects on the antioxidant activity of the sage seed. The main fatty acid of the sage seed was remarkably found as α-linolenic acid. The four irradiation levels caused significant differences in fatty acid composition by affecting all fatty acids except palmitic, palmitoleic, and eicosenoic acids. The dominant volatile compounds of control sage seed were found as β-pinene (18.81%) and limonene (15.60%). Higher doses of the irradiation decreased volatile components of sage seed. Clary sage seed including high omega-3 can be irradiated with low doses (≤ 2.5 kGy) of γ-irradiation. Clary sage is one of the most popular Salvia species in Turkey and many countries. Clary sage seed has approximately 29% oil content and this oil contains >50% of α-linolenic acid. γ-Irradiation is widely applied in the preservation of spice quality. The present study shows that the antioxidant activity of the clary sage seed is decreased by γ-irradiation. Additionally, higher doses of irradiation also decreased the volatile components of sage seed. Therefore, we suggest that clary sage seed which includes high levels of omega-3 should be irradiated with low doses (≤ 2.5 kGy) of γ-irradiation. © 2011 Institute of Food Technologists®

  9. Characterization of wood plastic composites made from landfill-derived plastic and sawdust: Volatile compounds and olfactometric analysis

    International Nuclear Information System (INIS)

    Félix, Juliana S.; Domeño, Celia; Nerín, Cristina

    2013-01-01

    Graphical abstract: This work details the characterization of VOCs of WPC, produced from residual materials which would have landfills as current destination, and evaluates their odor profile. Highlights: ► More than 140 volatile compounds were identified in raw materials and WPC products. ► Markers were related to the thermal degradation, sawdust or coupling agents. ► WPC prototype showed a characteristic odor profile of burnt, sweet and wax-like. ► Aldehydes, carboxylic acids, ketones and phenols were odor descriptors of WPC. - Abstract: Application of wood plastic composites (WPCs) obtained from recycled materials initially intended for landfill is usually limited by their composition, mainly focused on release of volatile organic compounds (VOCs) which could affect quality or human safety. The study of the VOCs released by a material is a requirement for new composite materials. Characterization and quantification of VOCs of several WPC produced with low density polyethylene (LDPE) and polyethylene/ethylene vinyl acetate (PE/EVA) films and sawdust were carried out, in each stage of production, by solid phase microextraction in headspace mode (HS-SPME) and gas chromatography–mass spectrometry (GC–MS). An odor profile was also obtained by HS-SPME and GC–MS coupled with olfactometry analysis. More than 140 compounds were observed in the raw materials and WPC samples. Some quantified compounds were considered WPC markers such as furfural, 2-methoxyphenol, N-methylphthalimide and 2,4-di-tert-butylphenol. Hexanoic acid, acetic acid, 2-methoxyphenol, acetylfuran, diacetyl, and aldehydes were the most important odorants. None of the VOCs were found to affect human safety for use of the WPC

  10. Characterization of wood plastic composites made from landfill-derived plastic and sawdust: Volatile compounds and olfactometric analysis

    Energy Technology Data Exchange (ETDEWEB)

    Félix, Juliana S., E-mail: jfelix@unizar.es [Department of Analytical Chemistry, I3A, EINA, University of Zaragoza (UNIZAR), Zaragoza 50018 (Spain); Domeño, Celia, E-mail: cdomeno@unizar.es [Department of Analytical Chemistry, I3A, EINA, University of Zaragoza (UNIZAR), Zaragoza 50018 (Spain); Nerín, Cristina, E-mail: cnerin@unizar.es [Department of Analytical Chemistry, I3A, EINA, University of Zaragoza (UNIZAR), Zaragoza 50018 (Spain)

    2013-03-15

    Graphical abstract: This work details the characterization of VOCs of WPC, produced from residual materials which would have landfills as current destination, and evaluates their odor profile. Highlights: ► More than 140 volatile compounds were identified in raw materials and WPC products. ► Markers were related to the thermal degradation, sawdust or coupling agents. ► WPC prototype showed a characteristic odor profile of burnt, sweet and wax-like. ► Aldehydes, carboxylic acids, ketones and phenols were odor descriptors of WPC. - Abstract: Application of wood plastic composites (WPCs) obtained from recycled materials initially intended for landfill is usually limited by their composition, mainly focused on release of volatile organic compounds (VOCs) which could affect quality or human safety. The study of the VOCs released by a material is a requirement for new composite materials. Characterization and quantification of VOCs of several WPC produced with low density polyethylene (LDPE) and polyethylene/ethylene vinyl acetate (PE/EVA) films and sawdust were carried out, in each stage of production, by solid phase microextraction in headspace mode (HS-SPME) and gas chromatography–mass spectrometry (GC–MS). An odor profile was also obtained by HS-SPME and GC–MS coupled with olfactometry analysis. More than 140 compounds were observed in the raw materials and WPC samples. Some quantified compounds were considered WPC markers such as furfural, 2-methoxyphenol, N-methylphthalimide and 2,4-di-tert-butylphenol. Hexanoic acid, acetic acid, 2-methoxyphenol, acetylfuran, diacetyl, and aldehydes were the most important odorants. None of the VOCs were found to affect human safety for use of the WPC.

  11. Aromatic hydrocarbon concentrations in sediments of Placentia Bay, Newfoundland

    International Nuclear Information System (INIS)

    Kiceniuk, J.W.

    1992-01-01

    A study was conducted to examine the potential for contamination of recent sediments with polycyclic aromatic hydrocarbons due to tanker and refinery activity in Placentia Bay, Newfoundland, an area without large local anthropogenic sources of aromatics. Sediment samples were taken from the vicinity of the Come By Chance refinery, Woody Island, Wild Cove, and Port Royal Arm, all in the north end of the bay. The samples were extracted by two methods, dichloromethane extraction of dried sediment for determination of total aromatic hydrocarbon content and hexane extraction of wet sediment for estimation of the bioavailability of hydrocarbons and determination of more volatile compounds. Class analysis of aromatic hydrocarbons was conducted on a NH 2 column with detection at 255 nm. Total concentrations of di-tricyclic aromatics were highest at the Woody Island site (0.6 μg/g). The sediments from the Come By Chance site, Wild Cove, and Port Royal Arm sediments contained 0.3, 0.1, and 0.2 μg/g respectively. The hexane extracts from Come By Chance were lowest in di-tricyclic aromatics (0.007 μg/g), with the other sites being equal in concentration (0.01 μg/g). It is evident from the study that aromatic hydrocarbon concentrations in Placentia Bay are elevated in some parts of the bay in the absence of local combustion sources, and that the most likely source is petroleum. 12 refs., 5 figs., 2 tabs

  12. Comparison of atmosphere/aquatic environment concentration ratio of volatile chlorinated hydrocarbons between temperate regions and Antarctica.

    Science.gov (United States)

    Zoccolillo, Lelio; Amendola, Luca; Insogna, Susanna

    2009-09-01

    For the purpose of understanding the transport and deposition mechanisms and the air-water distribution of some volatile chlorinated hydrocarbons (VCHCs), their atmosphere/aquatic environment concentration ratio was evaluated. In addition, for the purpose of differentiating VCHC behaviour in a temperate climate from its behaviour in a polar climate, the atmosphere/aquatic environment concentration ratio evaluated in matrices from temperate zones was compared with the concentration ratio evaluated in Antarctic matrices. In order to perform air samplings also at rigid Antarctic temperatures, the sampling apparatus, consisting of a diaphragm pump and canisters, was suitably modified. Chloroform, 1,1,1-trichloroethane, tetrachloromethane, 1,1,2-trichloroethylene and tetrachloroethylene were measured in air, water and snow using specific techniques composed of a purpose-made cryofocusing-trap-injector (for air samples) and a modified purge-and-trap injector (for aqueous samples) coupled to a gas chromatograph with mass spectrometric detection operating in selected ion monitoring mode. The VCHCs were retrieved in all the investigated matrices, both Italian and Antarctic, with concentrations varying from tens to thousands of ng m(-3) in air and from digits to hundreds of ng kg(-1) in water and snow. The atmosphere/aquatic environment concentration ratios were always found to be lower than 1. In particular, the Italian air/water concentration ratios were smaller than the Antarctic ones, by reason of the higher atmospheric photochemical activity in temperate zones. On the other hand, the Antarctic air/snow concentration ratios proved to be largely in favour of snow with respect to the Italian ratios, thus corroborating the hypothesis of a more efficient VCHC deposition mechanism and accumulation on Antarctic snow.

  13. Catalytic conversion of alcohols to hydrocarbons with low benzene content

    Energy Technology Data Exchange (ETDEWEB)

    Narula, Chaitanya K.; Davison, Brian H.; Keller, Martin

    2016-03-08

    A method for converting an alcohol to a hydrocarbon fraction having a lowered benzene content, the method comprising: converting said alcohol to a hydrocarbon fraction by contacting said alcohol, under conditions suitable for converting said alcohol to said hydrocarbon fraction, with a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon fraction, and contacting said hydrocarbon fraction with a benzene alkylation catalyst, under conditions suitable for alkylating benzene, to form alkylated benzene product in said hydrocarbon fraction. Also described is a catalyst composition useful in the method, comprising a mixture of (i) a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon, and (ii) a benzene alkylation catalyst, in which (i) and (ii) may be in a mixed or separated state. A reactor for housing the catalyst and conducting the reaction is also described.

  14. Catalytic conversion of alcohols to hydrocarbons with low benzene content

    Energy Technology Data Exchange (ETDEWEB)

    Narula, Chaitanya K.; Davison, Brian H.; Keller, Martin

    2016-09-06

    A method for converting an alcohol to a hydrocarbon fraction having a lowered benzene content, the method comprising: converting said alcohol to a hydrocarbon fraction by contacting said alcohol, under conditions suitable for converting said alcohol to said hydrocarbon fraction, with a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon fraction, and contacting said hydrocarbon fraction with a benzene alkylation catalyst, under conditions suitable for alkylating benzene, to form alkylated benzene product in said hydrocarbon fraction. Also described is a catalyst composition useful in the method, comprising a mixture of (i) a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon, and (ii) a benzene alkylation catalyst, in which (i) and (ii) may be in a mixed or separated state. A reactor for housing the catalyst and conducting the reaction is also described.

  15. Characterization of Chemical Composition of Pericarpium Citri Reticulatae Volatile Oil by Comprehensive Two-Dimensional Gas Chromatography with High-Resolution Time-of-Flight Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Kunming Qin

    2013-01-01

    Full Text Available Pericarpium Citri Reticulatae (Chenpi in Chinese has been widely used as an herbal medicine in Korea, China, and Japan. Chenpi extracts are used to treat indigestion and inflammatory syndromes of the respiratory tract such as bronchitis and asthma. This thesis will analyze chemical compositions of Chenpi volatile oil, which was performed by comprehensive two-dimensional gas chromatography with high-resolution time-of-flight mass spectrometry (GC × GC-HR-TOFMS. One hundred and sixty-seven components were tentatively identified, and terpene compounds are the main components of Chenpi volatile oil, a significant larger number than in previous studies. The majority of the eluted compounds, which were identified, were well separated as a result of high-resolution capability of the GC × GC method, which significantly reduces, the coelution. β-Elemene is tentatively qualified by means of GC × GC in tandem with high-resolution TOFMS detection, which plays an important role in enhancing the effects of many anticancer drugs and in reducing the side effects of chemotherapy. This study suggests that GC × GC-HR-TOFMS is suitable for routine characterization of chemical composition of volatile oil in herbal medicines.

  16. Biofilm comprising phototrophic, diazotrophic, and hydrocarbon-utilizing bacteria: a promising consortium in the bioremediation of aquatic hydrocarbon pollutants.

    Science.gov (United States)

    Al-Bader, Dhia; Kansour, Mayada K; Rayan, Rehab; Radwan, Samir S

    2013-05-01

    Biofilms harboring simultaneously anoxygenic and oxygenic phototrophic bacteria, diazotrophic bacteria, and hydrocarbon-utilizing bacteria were established on glass slides suspended in pristine and oily seawater. Via denaturing gradient gel electrophoresis analysis on PCR-amplified rRNA gene sequence fragments from the extracted DNA from biofilms, followed by band amplification, biofilm composition was determined. The biofilms contained anoxygenic phototrophs belonging to alphaproteobacteria; pico- and filamentous cyanobacteria (oxygenic phototrophs); two species of the diazotroph Azospirillum; and two hydrocarbon-utilizing gammaproteobacterial genera, Cycloclasticus and Oleibacter. The coexistence of all these microbial taxa with different physiologies in the biofilm makes the whole community nutritionally self-sufficient and adequately aerated, a condition quite suitable for the microbial biodegradation of aquatic pollutant hydrocarbons.

  17. Choice of volatile component of fluoroplastics containing varnishes for the equipment of radiation protection technique

    International Nuclear Information System (INIS)

    Shigorina, I.I.; Egorov, B.N.; Timofeeva, L.N.

    1978-01-01

    The problems of choosing the volatile part (v.p.) for varnishes on the basis of different flourocopolymers are considered. Ketones, esters, freons, dimethylformamide, tetrahydrofuran, aromatic and chlorinated hydrocarbons have been used as solvents. The volatile component has been estimated by the quality of the varnish film obtained (transparency, bubbles), viscosity of the varnishes, completeness of solvent volatility, porosity degree. Besides, analyzed are such factors as kinetics of solvent evaporation, working life time of varnishes, and the degree of their inflammability. Optimum solvents and their mixtures have been found for different grades of fluorolones. The possibility of producing fluorolone lackuers with a reduced degree of inflammability and of incombustible fluorolone varnishes is shown. Fluorolone varnishes find ever increasing application for radiation-protective coating of the equipment

  18. Pluto's surface composition and atmosphere

    Science.gov (United States)

    Young, L. A.; Gladstone, R.; Summers, M. E.; Strobel, D. F.; Kammer, J.; Hinson, D. P.; Grundy, W. M.; Cruikshank, D. P.; Protopapa, S.; Schmitt, B.; Stern, A.; Weaver, H. A., Jr.; Olkin, C.; Ennico Smith, K.

    2017-12-01

    New Horizons studied Pluto's N2-dominated neutral atmosphere through radio (at 4.2 cm with the REX radio experiment), solar and stellar occultations and airglow (at 52-187 nm with the Alice ultraviolet spectrograph), and imaging (with the LORRI and MVIC visible-wavelength cameras). It studied the plasma environment and solar wind interaction with in situ instruments (PEPPSI and SWAP). Contemporaneous observations of Pluto's atmosphere from Earth included a ground-based stellar occultation and ALMA observations of gaseous CO and HCN. Joint analysis of these datasets reveal a variable boundary layer; a stable lower atmosphere; radiative heating and cooling; haze production and hydrocarbon chemistry; diffusive equilibrium; and slower-than-expected escape. New Horizons studied Pluto's surface composition with the LEISA near-infrared spectral imager from 1.25 to 2.5 micron. Additional compositional information at higher spatial resolution came from the MVIC 4-channel color imager, which included a channel centered at 0.89 micron specifically designed to detect solid CH4. These instruments allow mapping of the volatiles N2, CO, and CH4, the surface expression of the H2O bedrock, and the dark, reddish material presumed to be tholins. These observations reveal a large equatorial basin (informally named Sptunik Planitia), filled with N2 ice with minor amounts of CO and CH4, surrounded by hills of CH4 and H2O ice. Broadly speaking, composition outside of Sptunik Planitia follows latitudinal banding, with dark, mainly volatile free terrains near the equator, with N2, CO, and CH4 at mid-northern latitudes, and mainly CH4 at high northern latitudes. Deviations from these broad trends are seen, and point to complex surface-atmosphere interactions at diurnal, seasonal, perennial, and million-year timescales.

  19. Effect of the type of frying culinary fat on volatile compounds isolated in fried pork loin chops by using SPME-GC-MS.

    Science.gov (United States)

    Ramírez, María Rosario; Estévez, Mario; Morcuende, David; Cava, Ramón

    2004-12-15

    The effect of the type of frying culinary fat (olive oil, sunflower oil, butter, and pig lard) on volatile compounds isolated from fried pork loin chops (m. Longissimus dorsi) was measured by SPME-GC-MS. Frying modified the fatty acid composition of lipids from pork loin chops, which tended to be similar to that of the culinary fat used to fry. Volatile compounds formed from the oxidation of fatty acids increased, such as aldehydes, ketones, alcohols, and hydrocarbons. Besides, each culinary fat used modified the volatile profiles in fried meat differently. Sunflower oil-fried pork loin chops presented the highest aldehyde aliphatic content, probably due to their highest content of polyunsaturated acids. Hexanal, the most abundant aldehyde in fried samples, presented the most elevated content in sunflower oil-fried pork loin chops. In addition, these samples presented more heterocyclic compounds from the Maillard reaction than other fried samples. Volatiles detected in olive oil-fried pork loin chops were mainly lipid-derived compounds such as pentan-1-ol, hexanal, hept-2-enal, nonanal, decanal, benzaldehyde, and nonan-2-one. Butter-fried pork loins were abundant in ketones with a high number of carbons (heptan-2-one, nonan-2-one, undecan-2-one, tridecanone, and heptadecan-2-one). Pig lard-fried pork loin chops presented some Strecker aldehydes isolated in only these samples, such as 2-methylbutanal and 3-(methylthio)propanal, and a sulfur compound (dimethyl disulfide) related to Strecker aldehydes.

  20. Emission factors of carbonaceous particulate matter and polycyclic aromatic hydrocarbons from residential solid fuel combustions

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Guofeng [Jiangsu Academy of Environmental Science, Nanjing (China). Inst. of Atmospheric Sciences

    2014-07-01

    Emission inventory is basic for the understanding of environmental behaviors and potential effects of compounds, however, current inventories are often associated with relatively high uncertainties. One important reason is the lack of emission factors, especially for the residential solid fuel combustion in developing countries. In the present study, emission factors of a group of pollutants including particulate matter, organic carbon, elemental carbon (sometimes known as black carbon) and polycyclic aromatic hydrocarbons were measured for a variety of residential solid fuels including coal, crop straw, wood, and biomass pellets in rural China. The study provided a large number of emission factors that can be further used in emission estimation. Composition profiles and isomer ratios were investigated and compared so as to be used in source apportionment. In addition, the present study identified and quantified the influence of factors like fuel moisture, volatile matter on emission performance.

  1. Volatile Components from Old Plum Brandies

    Directory of Open Access Journals (Sweden)

    Ninoslav Nikićević

    2005-01-01

    Full Text Available Gas chromatography and GC/MS methods were used to detect volatile components of three home-made natural old plum brandy samples and one sample of industrially-produced plum brandy. Gas chromatography and gas chromatography-mass spectrometric analysis of this extracts led to the identification of 99 components, including 46 esters, 7 hydrocarbons (alkanes and alkenes, 3 aldehydes, 9 alcohols, 1 lactone, 1 ketone, 8 acetals, 14 terpenes, 8 acids and 2 phenols. Ethyl esters of C8–C18 acids were the most abundant in all samples. In addition, the content of methanol, ethanol and higher alcohols C3–C5 was determined.

  2. Volatility of organic aerosol and its components in the Megacity of Paris

    Science.gov (United States)

    Paciga, A.; Karnezi, E.; Kostenidou, E.; Hildebrandt, L.; Psichoudaki, M.; Engelhart, G. J.; Lee, B.-H.; Crippa, M.; Prévôt, A. S. H.; Baltensperger, U.; Pandis, S. N.

    2015-08-01

    Using a mass transfer model and the volatility basis set, we estimate the volatility distribution for the organic aerosol (OA) components during summer and winter in Paris, France as part of the collaborative project MEGAPOLI. The concentrations of the OA components as a function of temperature were measured combining data from a thermodenuder and an aerosol mass spectrometer (AMS) with Positive Matrix Factorization (PMF) analysis. The hydrocarbon-like organic aerosol (HOA) had similar volatility distributions for the summer and winter campaigns with half of the material in the saturation concentration bin of 10 μg m-3 and another 35-40 % consisting of low and extremely low volatility organic compounds (LVOCs and ELVOCs, respectively). The winter cooking OA (COA) was more than an order of magnitude less volatile than the summer COA. The low volatility oxygenated OA (LV-OOA) factor detected in the summer had the lowest volatility of all the derived factors and consisted almost exclusively of ELVOCs. The volatility for the semi-volatile oxygenated OA (SV-OOA) was significantly higher than that of the LV-OOA, containing both semi-volatile organic components (SVOCs) and LVOCs. The oxygenated OA (OOA) factor in winter consisted of SVOCs (45 %), LVOCs (25 %) and ELVOCs (30 %). The volatility of marine OA (MOA) was higher than that of the other factors containing around 60 % SVOCs. The biomass burning OA (BBOA) factor contained components with a wide range of volatilities with significant contributions from both SVOCs (50 %) and LVOCs (30 %). Finally, combining the O : C ratio and volatility distributions of the various factors, we incorporated our results into the two-dimensional volatility basis set (2D-VBS). Our results show that the factors cover a broad spectrum of volatilities with no direct link between the average volatility and average O : C of the OA components. Agreement between our findings and previous publications is encouraging for our understanding of the

  3. Analysis of ORC (Organic Rankine Cycle) systems with pure hydrocarbons and mixtures of hydrocarbon and retardant for engine waste heat recovery

    International Nuclear Information System (INIS)

    Song, Jian; Gu, Chun-wei

    2015-01-01

    The Organic Rankine Cycle (ORC) has been demonstrated to be a promising technology for the recovery of engine waste heat. Systems with hydrocarbons as the working fluids exhibit good thermal performance. However, the flammability of hydrocarbons limits their practical applications because of safety concerns. This paper examines the potential of using mixtures of a hydrocarbon and a retardant in an ORC system for engine waste heat recovery. Refrigerants R141b and R11 are selected as the retardants and blended with the hydrocarbons to form zeotropic mixtures. The flammability is suppressed, and in addition, zeotropic mixtures provide better temperature matches with the heat source and sink, which reduces the exergy loss within the heat exchange processes, thereby increasing the cycle efficiency. Energetic and exergetic analysis of ORC systems with pure hydrocarbons and with mixtures of a hydrocarbon and a retardant are conducted and compared. The net power output and the second law efficiency are chosen as the evaluation criteria to select the suitable working fluid compositions and to define the optimal set of thermodynamic parameters. The simulation results reveal that the ORC system with cyclohexane/R141b (0.5/0.5) is optimal for this engine waste heat recovery case, thereby increasing the net power output of the system by 13.3% compared to pure cyclohexane. - Highlights: • ORC with zeotropic mixtures for engine waste heat recovery is discussed. • Energetic and exergetic analysis of ORC system are conducted. • Optimal mixture working fluid composition is identified. • Greater utilization of jacket water and lower irreversible loss are important.

  4. A study of light hydrocarbons (C{sub 4}-C{sub 1}3) in source rocks and petroleum fluid

    Energy Technology Data Exchange (ETDEWEB)

    Odden, Wenche

    2000-07-01

    This thesis consists of an introduction and five included papers. Of these, four papers are published in international journals and the fifth was submitted for review in April 2000. Emphasis has been placed on both naturally and artificially generated light hydrocarbons in petroleum fluids and their proposed source rocks as well as direct application of light hydrocarbons to oil/source rock correlations. Collectively, these papers describe a strategy for interpreting the source of the light hydrocarbons in original oils and condensates as well as the source of the asphaltene fractions from the reservoir fluids. The influence of maturity on light hydrocarbon composition has also been evaluated. The papers include (1) compositional data on the light hydrocarbons from thermal extracts and kerogen pyrolysates of sediment samples, (2) light hydrocarbon data of oils and condensates as well as the pyrolysis products of the asphaltenes from these fluids, (3) assessment of compositional alteration effects, such as selective losses of light hydrocarbons due to evaporation, thermal maturity, phase fractionation and biodegradation, (4) comparison of naturally and artificially generated light hydrocarbons, and (5) compound-specific carbon isotope analysis of the whole range of hydrocarbons of all sample types. (author)

  5. Volatile compound profile of sous-vide cooked lamb loins at different temperature-time combinations.

    Science.gov (United States)

    Roldán, Mar; Ruiz, Jorge; Del Pulgar, José Sánchez; Pérez-Palacios, Trinidad; Antequera, Teresa

    2015-02-01

    Lamb loins were subjected to sous-vide cooking at different combinations of temperature (60 and 80°C) and time (6 and 24h) to assess the effect on the volatile compound profile. Major chemical families in cooked samples were aliphatic hydrocarbons and aldehydes. The volatile compound profile in sous-vide cooked lamb loin was affected by the cooking temperature and time. Volatile compounds arising from lipid oxidation presented a high abundance in samples cooked at low or moderate cooking conditions (60°C for 6 and 24h, 80°C for 6h), while a more intense time and temperature combination (80°C for 24h) resulted on a higher concentration of volatile compounds arising from Strecker degradations of amino acids, as 2-methylpropanal and 3-methylbutanal. Therefore, sous-vide cooking at moderately high temperatures for long times would result in the formation of a stronger meaty flavor and roast notes in lamb meat. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Nutritional composition, bioactive compounds and volatile profile of cocoa beans from different regions of Cameroon.

    Science.gov (United States)

    Caprioli, Giovanni; Fiorini, Dennis; Maggi, Filippo; Nicoletti, Marcello; Ricciutelli, Massimo; Toniolo, Chiara; Prosper, Biapa; Vittori, Sauro; Sagratini, Gianni

    2016-06-01

    Analysis of the complex composition of cocoa beans provides fundamental information for evaluating the quality and nutritional aspects of cocoa-based food products, nutraceuticals and supplements. Cameroon, the world's fourth largest producer of cocoa, has been defined as "Africa in miniature" because of the variety it habitats. In order to evaluate the nutritional characteristics of cocoa beans from five different regions of Cameroon, we studied their polyphenolic content, volatile compounds and fatty acids composition. The High Performance Thin Layer Chromatography (HPTLC) analysis showed that the Mbalmayo sample had the highest content of theobromine (11.6 mg/g) and caffeic acid (2.1 mg/g), while the Sanchou sample had the highest level of (-)-epicatechin (142.9 mg/g). Concerning fatty acids, the lowest level of stearic acid was found in the Mbalmayo sample while the Bertoua sample showed the highest content of oleic acid. Thus, we confirmed that geographical origin influences the quality and nutritional characteristics of cocoa from these regions of Cameroon.

  7. Plasma-catalytic reforming of liquid hydrocarbons

    International Nuclear Information System (INIS)

    Nedybaliuk, O.A.; Chernyak, V.Ya; Kolgan, V.V.; Iukhymenko, V.V.; Solomenko, O.V.; Fedirchyk, I.I.; Martysh, E.V.; Demchina, V.P.; Klochok, N.V.; Dragnev, S.V.

    2015-01-01

    The series of experiments studying the plasma-catalytic reforming of liquid hydrocarbons was carried out. The dynamic plasma-liquid system based on a low-power rotating gliding arc with solid electrodes was used for the investigation of liquid hydrocarbons reforming process. Conversion was done via partial oxidation. A part of oxidant flow was activated by the discharge. Synthesis-gas composition was analysed by means of mass-spectrometry and gas-chromatography. A standard boiler, which operates on natural gas and LPG, was used for the burning of synthesis-gas

  8. Volatiles Of Lysimachia Paridiformis Var. Stenophylla, Lysimachia ...

    African Journals Online (AJOL)

    Twenty-one compounds were identified in the leaves of L. fortumei, accounting for 94.72% of the total volatile fraction. ... Conclusion: The results showed that the main composition types were similar in the three plants, but the content was different, which indicated that the similar composition types provided the same medical ...

  9. Polycyclic hydrocarbons - occurrence and determination

    International Nuclear Information System (INIS)

    Drzewicz, P.

    2007-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are a special group of atmospheric contaminants included in the persistent toxic substances (PTS) and also in the volatile organic compounds (VOC) groups. PAHs are present in the atmosphere and their origin can be due to anthropogenic activities. The main source of emission of PAH is the combustion of fossil fuels. Their specific characteristics, high volatility, mutagenic and carcinogenic power, easily transportable for long distances with the wind, make them important contaminants despite of the fact that they are present at very low concentrations. The report provides a review of main analytical methods applied in the determination of PAH in air. Special attention was devoted to heterocyclic PAH which contain one or more heteroatom (sulphur, oxygen, nitrogen) in the multiple-fused ring. The presence of heterocyclic PAH requires very complex, laborious and long lasting sample separation methods before analysis. In some cases, application of different temperature programs in gas chromatography allows to determine PAH and heterocyclic PAH in gaseous samples without sample pretreatment. Gas chromatography methods for the determination of PAH and heterocyclic PAH in the gas from combustion of light heating oil has been optimized. (author) [pl

  10. Receptor modeling of C2─C7 hydrocarbon sources at an urban background site in Zurich, Switzerland: changes between 1993─1994 and 2005─2006

    Directory of Open Access Journals (Sweden)

    S. Reimann

    2008-05-01

    Full Text Available Hourly measurements of 13 volatile hydrocarbons (C2–C7 were performed at an urban background site in Zurich (Switzerland in the years 1993–1994 and again in 2005–2006. For the separation of the volatile organic compounds by gas-chromatography (GC, an identical chromatographic column was used in both campaigns. Changes in hydrocarbon profiles and source strengths were recovered by positive matrix factorization (PMF. Eight and six factors could be related to hydrocarbon sources in 1993–1994 and in 2005–2006, respectively. The modeled source profiles were verified by hydrocarbon profiles reported in the literature. The source strengths were validated by independent measurements, such as inorganic trace gases (NOx, CO, SO2, methane (CH4, oxidized hydrocarbons (OVOCs and meteorological data (temperature, wind speed etc.. Our analysis suggests that the contribution of most hydrocarbon sources (i.e. road traffic, solvents use and wood burning decreased by a factor of about two to three between the early 1990s and 2005–2006. On the other hand, hydrocarbon losses from natural gas leakage remained at relatively constant levels (−20%. The estimated emission trends are in line with the results from different receptor-based approaches reported for other European cities. Their differences to national emission inventories are discussed.

  11. Natural attenuation of hydrocarbon polluted soils in Mexico

    International Nuclear Information System (INIS)

    Fernandez-Linares, L.; Rojas-Avelizapa, N.; Roldan-Carrillo, T.; Islas-Ramirez, M.

    2009-01-01

    Crude oil and hydrocarbon by-proudcts are the most common pollutants in Mexico. In the last years, the two terms, contamination and remediation have being re-defined; also, based on both the scientific advancement and the human risk, the sustentability of remediation technologies and the definition of cleaning levels has been taking place. In this context, the Natural Attenuation of soils is a viable and low cost remediation choice, defined as the degradation of organic compounds without artificial stimulation, through microbial activity including physical processes, such as volatilization, dilution, sorption, and hydraulic dispersion. (Author)

  12. Chemical fingerprinting of hydrocarbon-contamination in soil.

    Science.gov (United States)

    Boll, Esther S; Nejrup, Jens; Jensen, Julie K; Christensen, Jan H

    2015-03-01

    Chemical fingerprinting analyses of 29 hydrocarbon-contaminated soils were performed to assess the soil quality and determine the main contaminant sources. The results were compared to an assessment based on concentrations of the 16 priority polycyclic aromatic hydrocarbons pointed out by the U.S. Environmental Protection Agency (EPAPAH16) and total petroleum hydrocarbon (TPH). The chemical fingerprinting strategy proposed in this study included four tiers: (i) qualitative analysis of GC-FID chromatograms, (ii) comparison of the chemical composition of both un-substituted and alkyl-substituted polycyclic aromatic compounds (PACs), (iii) diagnostic ratios of selected PACs, and (iv) multivariate data analysis of sum-normalized PAC concentrations. The assessment criteria included quantitative analysis of 19 PACs and C1-C4 alkyl-substituted homologues of naphthalene, fluorene, dibenzothiophene, phenanthrene, pyrene, and chrysene; and 13 oxygenated polycyclic aromatic compounds (O-PACs). The chemical composition of un-substituted and alkyl-substituted PACs and visual interpretation of GC-FID chromatograms were in combination successful in differentiating pyrogenic and petrogenic hydrocarbon sources and in assessing weathering trends of hydrocarbon contamination in the soils. Multivariate data analysis of sum-normalized concentrations could as a stand-alone tool distinguish between hydrocarbon sources of petrogenic and pyrogenic origin, differentiate within petrogenic sources, and detect weathering trends. Diagnostic ratios of PACs were not successful for source identification of the heavily weathered hydrocarbon sources in the soils. The fingerprinting of contaminated soils revealed an underestimation of PACs in petrogenic contaminated soils when the assessment was based solely on EPAPAH16. As alkyl-substituted PACs are dominant in petrogenic sources, the evaluation of the total load of PACs based on EPAPAH16 was not representative. Likewise, the O-PACs are not

  13. Biodegradation Of Polycyclic Aromatic Hydrocarbons In Petroleum Oil Contaminating The Environment

    International Nuclear Information System (INIS)

    Partila, A.M.

    2013-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants in urban atmospheres (Chen et al., 2013). PAHs enter the environment via incomplete combustion of fossil fuels and accidental leakage of petroleum products, and as components of products such as creosote (Muckian et al., 2009). Due to PAHs carcinogenic activity, they have been included in the European Union (EU) and the Environmental Protection Agency (EPA) priority pollutant lists. Human exposure to PAHs occurs in three ways, inhalation, dermal contact and consumption of contaminated foods, which account for 88-98% of such contamination; in other words, diet is the major source of human exposure to these contaminants (Rey-Salgueiro et al., 2008). Both the World Health Organization and the UK Expert Panel on Air Quality Standards (EPAQS) have considered benzo(a)pyrene (BaP) as a marker of the carcinogenic potency of the polycyclic aromatic hydrocarbons (PAH) mixture (Delgado-Saborit et al., 2011). Polycyclic aromatic and heavier aliphatic hydrocarbons, which have a stable recalcitrant molecular structure, exhibit high hydrophobicity and low aqueous solubility, are not readily removed from soil through leaching and volatilization (Brassington et al., 2007). The hydrophobicity of PAHs limits desorption to the aqueous phase (Donlon et al., 2002). Six main ways of dissipation, i.e. disappearance, are recognized in the environment: volatilization, photooxidation, Aim of the Work chemical oxidation, sorption, leaching and biodegradation. Microbial degradation is considered to be the main process involved in the dissipation of PAH (Yuan et al., 2002). Thus, more and more research interests are turning to the biodegradation of PAHs. Some microorganisms can utilize PAHs as a source of carbon and energy so that PAHs can be degraded to carbon dioxide and water, or transformed to other nontoxic or low-toxic substances (Perelo, 2010). Compared with other physical and chemical methods such as combustion

  14. Stochastic volatility of volatility in continuous time

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole; Veraart, Almut

    This paper introduces the concept of stochastic volatility of volatility in continuous time and, hence, extends standard stochastic volatility (SV) models to allow for an additional source of randomness associated with greater variability in the data. We discuss how stochastic volatility...... of volatility can be defined both non-parametrically, where we link it to the quadratic variation of the stochastic variance process, and parametrically, where we propose two new SV models which allow for stochastic volatility of volatility. In addition, we show that volatility of volatility can be estimated...

  15. [The composition of volatile components of cepe (Boletus edulis) and oyster mushrooms (Pleurotus ostreatus)].

    Science.gov (United States)

    Misharina, T A; Mukhutdinova, S M; Zharikova, G G; Terenina, M B; Krikunova, N I

    2009-01-01

    The composition of aroma compounds in cooked and canned cepe (Boletus edulis) and in cooked oyster mushrooms (Pleurotus ostreatus) is studied using capillary gas chromatography and chromatography-mass spectrometry. It is found that unsaturated alcohols and ketones containing eight atoms of carbon determine the aroma of raw mushrooms and take part in the formation of the aroma of cooked mushrooms as well. The content of these compounds was the highest in canned cepes. In oyster mushrooms, the concentration of these alcohols and ketones was lower in comparison with cepes. The content of aliphatic and aromatic aldehydes was much higher in oyster mushrooms. Volatile aliphatic and heterocyclic Maillard reaction products and isomeric octenols and octenones formed the aroma of cooked and canned mushrooms.

  16. The reformation of liquid hydrocarbons in an aqueous discharge reactor

    International Nuclear Information System (INIS)

    Zhang, Xuming; Cha, Min Suk

    2015-01-01

    We present an aqueous discharge reactor for the reformation of liquid hydrocarbons. To increase a dielectric constant of a liquid medium, we added distilled water to iso-octane and n-dodecane. As expected, we found decreased discharge onset voltage and increased discharge power with increased water content. Results using optical emission spectroscopy identified OH radicals and O atoms as the predominant oxidative reactive species with the addition of water. Enriched CH radicals were also visualized, evidencing the existence of cascade carbon–carbon cleavage and dehydrogenation processes in the aqueous discharge. The gaseous product consisted primarily of hydrogen, carbon monoxide, and unsaturated hydrocarbons. The composition of the product was readily adjustable by varying the volume of water added, which demonstrated a significant difference in composition with respect to the tested liquid hydrocarbon. In this study, we found no presence of CO 2 emissions or the contamination of the reactor by solid carbon deposition. These findings offer a new approach to the reforming processes of liquid hydrocarbons and provide a novel concept for the design of a practical and compact plasma reformer. (paper)

  17. Volatile and Organic Compositions of Sedimentary Rocks in Yellowknife Bay, Gale Crater, Mars

    Science.gov (United States)

    Ming, D. W.; Archer, P. D.; Glavin, D. P.; Eigenbrode, J. L.; Franz, H. B.; Sutter, B.; Brunner, A. E.; Stern, J. C.; Freissinet, C.; McAdam, A. C.; Mahaffy, P. R.; Cabane, M.; Coll, P.; Campbell, J. L.; Atreya, S. K.; Niles, P. B.; Bell, J. F.; Bish, D. L.; Brinckerhoff, W. B.; Buch, A.; Conrad, P. G.; Des Marais, D. J.; Ehlmann, B. L.; Fairén, A. G.; Farley, K.; Flesch, G. J.; Francois, P.; Gellert, R.; Grant, J. A.; Grotzinger, J. P.; Gupta, S.; Herkenhoff, K. E.; Hurowitz, J. A.; Leshin, L. A.; Lewis, K. W.; McLennan, S. M.; Miller, K. E.; Moersch, J.; Morris, R. V.; Navarro-González, R.; Pavlov, A. A.; Perrett, G. M.; Pradler, I.; Squyres, S. W.; Summons, R. E.; Steele, A.; Stolper, E. M.; Sumner, D. Y.; Szopa, C.; Teinturier, S.; Trainer, M. G.; Treiman, A. H.; Vaniman, D. T.; Vasavada, A. R.; Webster, C. R.; Wray, J. J.; Yingst, R. A.; Kemppinen, Osku; Bridges, Nathan; Johnson, Jeffrey R.; Minitti, Michelle; Cremers, David; Edgar, Lauren; Farmer, Jack; Godber, Austin; Wadhwa, Meenakshi; Wellington, Danika; McEwan, Ian; Newman, Claire; Richardson, Mark; Charpentier, Antoine; Peret, Laurent; King, Penelope; Blank, Jennifer; Weigle, Gerald; Schmidt, Mariek; Li, Shuai; Milliken, Ralph; Robertson, Kevin; Sun, Vivian; Baker, Michael; Edwards, Christopher; Ehlmann, Bethany; Griffes, Jennifer; Newcombe, Megan; Pilorget, Cedric; Rice, Melissa; Siebach, Kirsten; Stack, Katie; Brunet, Claude; Hipkin, Victoria; Léveillé, Richard; Marchand, Geneviève; Sánchez, Pablo Sobrón; Favot, Laurent; Cody, George; Flückiger, Lorenzo; Lees, David; Nefian, Ara; Martin, Mildred; Gailhanou, Marc; Westall, Frances; Israël, Guy; Agard, Christophe; Baroukh, Julien; Donny, Christophe; Gaboriaud, Alain; Guillemot, Philippe; Lafaille, Vivian; Lorigny, Eric; Paillet, Alexis; Pérez, René; Saccoccio, Muriel; Yana, Charles; Armiens-Aparicio, Carlos; Rodríguez, Javier Caride; Blázquez, Isaías Carrasco; Gómez, Felipe Gómez; Gómez-Elvira, Javier; Hettrich, Sebastian; Malvitte, Alain Lepinette; Jiménez, Mercedes Marín; Martínez-Frías, Jesús; Martín-Soler, Javier; Martín-Torres, F. Javier; Jurado, Antonio Molina; Mora-Sotomayor, Luis; Caro, Guillermo Muñoz; López, Sara Navarro; Peinado-González, Verónica; Pla-García, Jorge; Manfredi, José Antonio Rodriguez; Romeral-Planelló, Julio José; Fuentes, Sara Alejandra Sans; Martinez, Eduardo Sebastian; Redondo, Josefina Torres; Urqui-O'Callaghan, Roser; Mier, María-Paz Zorzano; Chipera, Steve; Lacour, Jean-Luc; Mauchien, Patrick; Sirven, Jean-Baptiste; Manning, Heidi; Hayes, Alexander; Joseph, Jonathan; Sullivan, Robert; Thomas, Peter; Dupont, Audrey; Lundberg, Angela; Melikechi, Noureddine; Mezzacappa, Alissa; DeMarines, Julia; Grinspoon, David; Reitz, Günther; Prats, Benito; Atlaskin, Evgeny; Genzer, Maria; Harri, Ari-Matti; Haukka, Harri; Kahanpää, Henrik; Kauhanen, Janne; Kemppinen, Osku; Paton, Mark; Polkko, Jouni; Schmidt, Walter; Siili, Tero; Fabre, Cécile; Wilhelm, Mary Beth; Poitrasson, Franck; Patel, Kiran; Gorevan, Stephen; Indyk, Stephen; Paulsen, Gale; Schieber, Juergen; Gondet, Brigitte; Langevin, Yves; Geffroy, Claude; Baratoux, David; Berger, Gilles; Cros, Alain; d'Uston, Claude; Forni, Olivier; Gasnault, Olivier; Lasue, Jérémie; Lee, Qiu-Mei; Maurice, Sylvestre; Meslin, Pierre-Yves; Pallier, Etienne; Parot, Yann; Pinet, Patrick; Schröder, Susanne; Toplis, Mike; Lewin, Éric; Brunner, Will; Heydari, Ezat; Achilles, Cherie; Oehler, Dorothy; Coscia, David; Israël, Guy; Dromart, Gilles; Robert, François; Sautter, Violaine; Le Mouélic, Stéphane; Mangold, Nicolas; Nachon, Marion; Stalport, Fabien; Raulin, François; Cameron, James; Clegg, Sam; Cousin, Agnès; DeLapp, Dorothea; Dingler, Robert; Jackson, Ryan Steele; Johnstone, Stephen; Lanza, Nina; Little, Cynthia; Nelson, Tony; Wiens, Roger C.; Williams, Richard B.; Jones, Andrea; Kirkland, Laurel; Baker, Burt; Cantor, Bruce; Caplinger, Michael; Davis, Scott; Duston, Brian; Edgett, Kenneth; Fay, Donald; Hardgrove, Craig; Harker, David; Herrera, Paul; Jensen, Elsa; Kennedy, Megan R.; Krezoski, Gillian; Krysak, Daniel; Lipkaman, Leslie; Malin, Michael; McCartney, Elaina; McNair, Sean; Nixon, Brian; Posiolova, Liliya; Ravine, Michael; Salamon, Andrew; Saper, Lee; Stoiber, Kevin; Supulver, Kimberley; Van Beek, Jason; Van Beek, Tessa; Zimdar, Robert; French, Katherine Louise; Iagnemma, Karl; Miller, Kristen; Goesmann, Fred; Goetz, Walter; Hviid, Stubbe; Johnson, Micah; Lefavor, Matthew; Lyness, Eric; Breves, Elly; Dyar, M. Darby; Fassett, Caleb; Blake, David F.; Bristow, Thomas; Edwards, Laurence; Haberle, Robert; Hoehler, Tori; Hollingsworth, Jeff; Kahre, Melinda; Keely, Leslie; McKay, Christopher; Wilhelm, Mary Beth; Bleacher, Lora; Choi, David; Dworkin, Jason P.; Floyd, Melissa; Garvin, James; Harpold, Daniel; Jones, Andrea; Martin, David K.; Raaen, Eric; Smith, Michael D.; Tan, Florence; Meyer, Michael; Posner, Arik; Voytek, Mary; Anderson, Robert C.; Aubrey, Andrew; Beegle, Luther W.; Behar, Alberto; Blaney, Diana; Brinza, David; Calef, Fred; Christensen, Lance; Crisp, Joy A.; DeFlores, Lauren; Feldman, Jason; Feldman, Sabrina; Jun, Insoo; Keymeulen, Didier; Maki, Justin; Mischna, Michael; Morookian, John Michael; Parker, Timothy; Pavri, Betina; Schoppers, Marcel; Sengstacken, Aaron; Simmonds, John J.; Spanovich, Nicole; Juarez, Manuel de la Torre; Yen, Albert; Cucinotta, Francis; Jones, John H.; Rampe, Elizabeth; Nolan, Thomas; Fisk, Martin; Radziemski, Leon; Barraclough, Bruce; Bender, Steve; Berman, Daniel; Dobrea, Eldar Noe; Tokar, Robert; Williams, Rebecca M. E.; Cleghorn, Timothy; Huntress, Wesley; Manhès, Gérard; Hudgins, Judy; Olson, Timothy; Stewart, Noel; Sarrazin, Philippe; Vicenzi, Edward; Wilson, Sharon A.; Bullock, Mark; Ehresmann, Bent; Hamilton, Victoria; Hassler, Donald; Peterson, Joseph; Rafkin, Scot; Zeitlin, Cary; Fedosov, Fedor; Golovin, Dmitry; Karpushkina, Natalya; Kozyrev, Alexander; Litvak, Maxim; Malakhov, Alexey; Mitrofanov, Igor; Mokrousov, Maxim; Nikiforov, Sergey; Prokhorov, Vasily; Sanin, Anton; Tretyakov, Vladislav; Varenikov, Alexey; Vostrukhin, Andrey; Kuzmin, Ruslan; Clark, Benton; Wolff, Michael; Botta, Oliver; Drake, Darrell; Bean, Keri; Lemmon, Mark; Schwenzer, Susanne P.; Anderson, Ryan B.; Lee, Ella Mae; Sucharski, Robert; Hernández, Miguel Ángel de Pablo; Ávalos, Juan José Blanco; Ramos, Miguel; Kim, Myung-Hee; Malespin, Charles; Plante, Ianik; Muller, Jan-Peter; Ewing, Ryan; Boynton, William; Downs, Robert; Fitzgibbon, Mike; Harshman, Karl; Morrison, Shaunna; Dietrich, William; Kortmann, Onno; Palucis, Marisa; Williams, Amy; Lugmair, Günter; Wilson, Michael A.; Rubin, David; Jakosky, Bruce; Balic-Zunic, Tonci; Frydenvang, Jens; Jensen, Jaqueline Kløvgaard; Kinch, Kjartan; Koefoed, Asmus; Madsen, Morten Bo; Stipp, Susan Louise Svane; Boyd, Nick; VanBommel, Scott; Jacob, Samantha; Owen, Tobias; Rowland, Scott; Atlaskin, Evgeny; Savijärvi, Hannu; Boehm, Eckart; Böttcher, Stephan; Burmeister, Sönke; Guo, Jingnan; Köhler, Jan; García, César Martín; Mueller-Mellin, Reinhold; Wimmer-Schweingruber, Robert; Bridges, John C.; McConnochie, Timothy; Benna, Mehdi; Bower, Hannah; Blau, Hannah; Boucher, Thomas; Carmosino, Marco; Elliott, Harvey; Halleaux, Douglas; Rennó, Nilton; Wong, Michael; Pepin, Robert; Elliott, Beverley; Spray, John; Thompson, Lucy; Gordon, Suzanne; Newsom, Horton; Ollila, Ann; Williams, Joshua; Vasconcelos, Paulo; Bentz, Jennifer; Nealson, Kenneth; Popa, Radu; Kah, Linda C.; Tate, Christopher; Day, Mackenzie; Kocurek, Gary; Hallet, Bernard; Sletten, Ronald; Francis, Raymond; McCullough, Emily; Cloutis, Ed; ten Kate, Inge Loes; Kuzmin, Ruslan; Arvidson, Raymond; Fraeman, Abigail; Scholes, Daniel; Slavney, Susan; Stein, Thomas; Ward, Jennifer; Berger, Jeffrey; Moores, John E.

    2014-01-01

    H2O, CO2, SO2, O2, H2, H2S, HCl, chlorinated hydrocarbons, NO, and other trace gases were evolved during pyrolysis of two mudstone samples acquired by the Curiosity rover at Yellowknife Bay within Gale crater, Mars. H2O/OH-bearing phases included 2:1 phyllosilicate(s), bassanite, akaganeite, and amorphous materials. Thermal decomposition of carbonates and combustion of organic materials are candidate sources for the CO2. Concurrent evolution of O2 and chlorinated hydrocarbons suggests the presence of oxychlorine phase(s). Sulfides are likely sources for sulfur-bearing species. Higher abundances of chlorinated hydrocarbons in the mudstone compared with Rocknest windblown materials previously analyzed by Curiosity suggest that indigenous martian or meteoritic organic carbon sources may be preserved in the mudstone; however, the carbon source for the chlorinated hydrocarbons is not definitively of martian origin.

  18. Volatile and organic compositions of sedimentary rocks in Yellowknife Bay, Gale crater, Mars

    Science.gov (United States)

    Ming, D. W.; Archer, P.D.; Glavin, D.P.; Eigenbrode, J.L.; Franz, H.B.; Sutter, B.; Brunner, A.E.; Stern, J.C.; Freissinet, C.; McAdam, A.C.; Mahaffy, P.R.; Cabane, M.; Coll, P.; Campbell, J.L.; Atreya, S.K.; Niles, P.B.; Bell, J.F.; Bish, D.L.; Brinckerhoff, W.B.; Buch, A.; Conrad, P.G.; Des Marais, D.J.; Ehlmann, B.L.; Fairén, A.G.; Farley, K.; Flesch, G.J.; Francois, P.; Gellert, Ralf; Grant, J. A.; Grotzinger, J.P.; Gupta, S.; Herkenhoff, K. E.; Hurowitz, J.A.; Leshin, L.A.; Lewis, K.W.; McLennan, S.M.; Miller, Karl E.; Moersch, J.; Morris, R.V.; Navarro- González, R.; Pavlov, A.A.; Perrett, G.M.; Pradler, I.; Squyres, S. W.; Summons, Roger E.; Steele, A.; Stolper, E.M.; Sumner, D.Y.; Szopa, C.; Teinturier, S.; Trainer, M.G.; Treiman, A.H.; Vaniman, D.T.; Vasavada, A.R.; Webster, C.R.; Wray, J.J.; Yingst, R.A.

    2014-01-01

    H2O, CO2, SO2, O2, H2, H2S, HCl, chlorinated hydrocarbons, NO, and other trace gases were evolved during pyrolysis of two mudstone samples acquired by the Curiosity rover at Yellowknife Bay within Gale crater, Mars. H2O/OH-bearing phases included 2:1 phyllosilicate(s), bassanite, akaganeite, and amorphous materials. Thermal decomposition of carbonates and combustion of organic materials are candidate sources for the CO2. Concurrent evolution of O2 and chlorinated hydrocarbons suggests the presence of oxychlorine phase(s). Sulfides are likely sources for sulfur-bearing species. Higher abundances of chlorinated hydrocarbons in the mudstone compared with Rocknest windblown materials previously analyzed by Curiosity suggest that indigenous martian or meteoritic organic carbon sources may be preserved in the mudstone; however, the carbon source for the chlorinated hydrocarbons is not definitively of martian origin.

  19. Volatile and organic compositions of sedimentary rocks in Yellowknife Bay, Gale crater, Mars.

    Science.gov (United States)

    Ming, D W; Archer, P D; Glavin, D P; Eigenbrode, J L; Franz, H B; Sutter, B; Brunner, A E; Stern, J C; Freissinet, C; McAdam, A C; Mahaffy, P R; Cabane, M; Coll, P; Campbell, J L; Atreya, S K; Niles, P B; Bell, J F; Bish, D L; Brinckerhoff, W B; Buch, A; Conrad, P G; Des Marais, D J; Ehlmann, B L; Fairén, A G; Farley, K; Flesch, G J; Francois, P; Gellert, R; Grant, J A; Grotzinger, J P; Gupta, S; Herkenhoff, K E; Hurowitz, J A; Leshin, L A; Lewis, K W; McLennan, S M; Miller, K E; Moersch, J; Morris, R V; Navarro-González, R; Pavlov, A A; Perrett, G M; Pradler, I; Squyres, S W; Summons, R E; Steele, A; Stolper, E M; Sumner, D Y; Szopa, C; Teinturier, S; Trainer, M G; Treiman, A H; Vaniman, D T; Vasavada, A R; Webster, C R; Wray, J J; Yingst, R A

    2014-01-24

    H2O, CO2, SO2, O2, H2, H2S, HCl, chlorinated hydrocarbons, NO, and other trace gases were evolved during pyrolysis of two mudstone samples acquired by the Curiosity rover at Yellowknife Bay within Gale crater, Mars. H2O/OH-bearing phases included 2:1 phyllosilicate(s), bassanite, akaganeite, and amorphous materials. Thermal decomposition of carbonates and combustion of organic materials are candidate sources for the CO2. Concurrent evolution of O2 and chlorinated hydrocarbons suggests the presence of oxychlorine phase(s). Sulfides are likely sources for sulfur-bearing species. Higher abundances of chlorinated hydrocarbons in the mudstone compared with Rocknest windblown materials previously analyzed by Curiosity suggest that indigenous martian or meteoritic organic carbon sources may be preserved in the mudstone; however, the carbon source for the chlorinated hydrocarbons is not definitively of martian origin.

  20. Noble gas and hydrocarbon tracers in multiphase unconventional hydrocarbon systems: Toward integrated advanced reservoir simulators

    Science.gov (United States)

    Darrah, T.; Moortgat, J.; Poreda, R. J.; Muehlenbachs, K.; Whyte, C. J.

    2015-12-01

    Although hydrocarbon production from unconventional energy resources has increased dramatically in the last decade, total unconventional oil and gas recovery from black shales is still less than 25% and 9% of the totals in place, respectively. Further, the majority of increased hydrocarbon production results from increasing the lengths of laterals, the number of hydraulic fracturing stages, and the volume of consumptive water usage. These strategies all reduce the economic efficiency of hydrocarbon extraction. The poor recovery statistics result from an insufficient understanding of some of the key physical processes in complex, organic-rich, low porosity formations (e.g., phase behavior, fluid-rock interactions, and flow mechanisms at nano-scale confinement and the role of natural fractures and faults as conduits for flow). Noble gases and other hydrocarbon tracers are capably of recording subsurface fluid-rock interactions on a variety of geological scales (micro-, meso-, to macro-scale) and provide analogs for the movement of hydrocarbons in the subsurface. As such geochemical data enrich the input for the numerical modeling of multi-phase (e.g., oil, gas, and brine) fluid flow in highly heterogeneous, low permeability formations Herein we will present a combination of noble gas (He, Ne, Ar, Kr, and Xe abundances and isotope ratios) and molecular and isotopic hydrocarbon data from a geographically and geologically diverse set of unconventional hydrocarbon reservoirs in North America. Specifically, we will include data from the Marcellus, Utica, Barnett, Eagle Ford, formations and the Illinois basin. Our presentation will include geochemical and geological interpretation and our perspective on the first steps toward building an advanced reservoir simulator for tracer transport in multicomponent multiphase compositional flow (presented separately, in Moortgat et al., 2015).

  1. Development of oil hydrocarbon fingerprinting and identification techniques

    International Nuclear Information System (INIS)

    Wang Zhendi; Fingas, Merv F.

    2003-01-01

    Oil, refined product, and pyrogenic hydrocarbons are the most frequently discovered contaminants in the environment. To effectively determine the fate of spilled oil in the environment and to successfully identify source(s) of spilled oil and petroleum products is, therefore, extremely important in many oil-related environmental studies and liability cases. This article briefly reviews the recent development of chemical analysis methodologies which are most frequently used in oil spill characterization and identification studies and environmental forensic investigations. The fingerprinting and data interpretation techniques discussed include oil spill identification protocol, tiered analytical approach, generic features and chemical composition of oils, effects of weathering on hydrocarbon fingerprinting, recognition of distribution patterns of petroleum hydrocarbons, oil type screening and differentiation, analysis of 'source-specific marker' compounds, determination of diagnostic ratios of specific oil constituents, stable isotopic analysis, application of various statistical and numerical analysis tools, and application of other analytical techniques. The issue of how biogenic and pyrogenic hydrocarbons are distinguished from petrogenic hydrocarbons is also addressed

  2. Composição volátil dos defeitos intrínsecos do café por CG/EM-headspace Volatile composition of intrinsic defective coffee beans by GC/MS-headspace

    Directory of Open Access Journals (Sweden)

    Raquel D. C. C. Bandeira

    2009-01-01

    Full Text Available About 20% of Brazilian raw coffee production is considered inappropriate for exportation. Consequently, these beans are incorporated to good quality beans in the Brazilian market. This by-product of coffee industry is called PVA due to the presence of black (P, green (V and sour (A defective beans which are known to contribute considerably for cup quality decrease. Data on the volatile composition of Brazilian defective coffee beans are scarce. In this study, we evaluated the volatile composition of immature, black-immature, black defective beans and PVA compared to good quality beans. Potential defective beans markers were identified.

  3. Constraining the volatile fraction of planets from transit observations

    Science.gov (United States)

    Alibert, Y.

    2016-06-01

    Context. The determination of the abundance of volatiles in extrasolar planets is very important as it can provide constraints on transport in protoplanetary disks and on the formation location of planets. However, constraining the internal structure of low-mass planets from transit measurements is known to be a degenerate problem. Aims: Using planetary structure and evolution models, we show how observations of transiting planets can be used to constrain their internal composition, in particular the amount of volatiles in the planetary interior, and consequently the amount of gas (defined in this paper to be only H and He) that the planet harbors. We first explore planets that are located close enough to their star to have lost their gas envelope. We then concentrate on planets at larger distances and show that the observation of transiting planets at different evolutionary ages can provide statistical information on their internal composition, in particular on their volatile fraction. Methods: We computed the evolution of low-mass planets (super-Earths to Neptune-like) for different fractions of volatiles and gas. We used a four-layer model (core, silicate mantle, icy mantle, and gas envelope) and computed the internal structure of planets for different luminosities. With this internal structure model, we computed the internal and gravitational energy of planets, which was then used to derive the time evolution of the planet. Since the total energy of a planet depends on its heat capacity and density distribution and therefore on its composition, planets with different ice fractions have different evolution tracks. Results: We show for low-mass gas-poor planets that are located close to their central star that assuming evaporation has efficiently removed the entire gas envelope, it is possible to constrain the volatile fraction of close-in transiting planets. We illustrate this method on the example of 55 Cnc e and show that under the assumption of the absence of

  4. Fundamental mechanisms for conversion of volatiles in biomass and waste combustion. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Glarborg, P.; Hindiyarti, L.; Marshall, P.; Livbjerg, H.; Dagaut, P.; Jensen, Anker; Frandsen, Flemming

    2007-03-15

    This project deals with the volatile oxidation chemistry in biomass and waste fired systems, emphasizing reactions important for pollutants emissions (NO{sub x}, SO{sub 2}, HCl, aerosols). The project aims to extend existing models and databases with a number of chemical subsystems that are presently not well understood, but are particularly important in connection with combustion of biomass and waste. The project is divided into 3 tasks. Task 1: Conversion of chlorine, sulfur and alkali gas phase components in combustion of biomass. Task 2: Formation mechanisms for NO{sub x} in the freeboard of grate combustion of biomass. Task 3: Oxidation mechanisms for oxygenated hydrocarbons in the volatiles from pyrolysis of biomass. (au)

  5. Volatiles and Nonvolatiles in Flourensia campestris Griseb. (Asteraceae), How Much Do Capitate Glandular Trichomes Matter?

    Science.gov (United States)

    Piazza, Leonardo A; López, Daniela; Silva, Mariana P; López Rivilli, Marisa J; Tourn, Mónica G; Cantero, Juan J; Scopel, Ana L

    2018-03-01

    The distribution and ultrastructure of capitate glandular trichomes (GTs) in Flourensia species (Asteraceae) have been recently elucidated, but their metabolic activity and potential biological function remain unexplored. Selective nonvolatile metabolites from isolated GTs were strikingly similar to those found on leaf surfaces. The phytotoxic allelochemical sesquiterpene (-)-hamanasic acid A ((-)-HAA) was the major constituent (ca. 40%) in GTs. Although GTs are quaternary ammonium compounds (QACs)-accumulating species, glycine betaine was not found in GTs; it was only present in the leaf mesophyll. Two (-)-HAA accompanying surface secreted products: compounds 4-hydroxyacetophenone (piceol; 1) and 2-hydroxy-5-methoxyacetophenone (2), which were isolated and fully characterized (GC/MS, NMR), were present in the volatiles found in GTs. The essential oils of fresh leaves revealed ca. 33% monoterpenes, 26% hydrocarbon- and 30% oxygenated sesquiterpenes, most of them related to cadinene and bisabolene derivatives. Present results suggest a main role of GTs in determining the volatile and nonvolatile composition of F. campestris leaves. Based on the known activities of the compounds identified, it can be suggested that GTs in F. campestris would play key ecological functions in plant-pathogen and plant-plant interactions. In addition, the strikingly high contribution of compounds derived from cadinene and bisabolene pathways, highlights the potential of this species as a source of high-valued bioproducts. © 2018 Wiley-VHCA AG, Zurich, Switzerland.

  6. Analysis of volatile compounds from Iberian hams: a review

    Directory of Open Access Journals (Sweden)

    Narváez-Rivas, M.

    2012-10-01

    Full Text Available This article provides information on the study of the volatile compounds in raw and dry-cured Iberian hams. Different volatile compounds are identified and studies carried out by different authors are presented. This article reviews the analytical methods that have been used to determine the different volatiles of these samples. Furthermore, all volatile compounds identified (a total of 411 volatiles have been collected in several tables according to different series of compounds: hydrocarbons, aldehydes, ketones, alcohols, esters and ethers, lactones, terpenes and chloride compounds, nitrogenous compounds, sulfur compounds and carboxylic acids. This review can be useful in subsequent research due to the complexity of the study.

    En este artículo se proporciona información sobre el estudio de los compuestos volátiles del jamón ibérico tanto fresco como curado. Se presentan los diferentes compuestos volátiles identificados por distintos autores. Además, se evalúan los métodos analíticos que han sido utilizados para determinar dichos compuestos volátiles en este tipo de muestras. Todos los compuestos identificados y descritos en esta revisión (un total de 411 compuestos volátiles han sido agrupados en diversas tablas de acuerdo a las diferentes familias a que pertenecen: hidrocarburos, aldehídos, cetonas, alcoholes, ésteres y éteres, lactonas, terpenos, compuestos halogenados, compuestos nitrogenados, compuestos de azufre y ácidos carboxílicos. Debido a la complejidad de este estudio, la presente revisión puede ser muy útil en investigaciones posteriores.

  7. Solid phase microextraction: measurement of volatile organic compounds (VOCs) in Dhaka City air pollution.

    Science.gov (United States)

    Hussam, A; Alauddin, M; Khan, A H; Chowdhury, D; Bibi, H; Bhattacharjee, M; Sultana, S

    2002-08-01

    A solid phase microextraction (SPME) technique was applied for the sampling of volatile organic compounds (VOCs) in ambient air polluted by two stroke autorickshaw engines and automobile exhausts in Dhaka city, Bangladesh. Analysis was carried out by capillary gas chromatography (GC) and GC-mass spectrometry (MS). The methodology was tested by insitu sampling of an aromatic hydrocarbon mixture gas standard with a precision of +/-5% and an average accuracy of 1-20%. The accuracy for total VOCs concentration measurement was about 7%. VOC's in ambient air were collected by exposing the SPME fiber at four locations in Dhaka city. The chromatograms showed signature similar to that of unburned gasoline (petrol) and weathered diesel containing more than 200 organic compounds; some of these compounds were positively identified. These are normal hydrocarbons pentane (n-C5H2) through nonacosane (n-C29H60), aromatic hydrocarbons: benzene, toluene, ethylbenzene, n-propylbenzene, n-butylbenzene, 1,3,5-trimethylbenzene, xylenes, and 1-isocyanato-3-methoxybenzene. Two samples collected near an autorickshaw station contained 783000 and 1479000 microg/m3 of VOCs. In particular, the concentration of toluene was 50-100 times higher than the threshold limiting value of 2000 microg/m3. Two other samples collected on street median showed 135000 microg/m3 and 180000 microg/m3 of total VOCs. The method detection limit of the technique for most semi-volatile organic compounds was 1 microg/m3.

  8. Correlation between mandibular gland secretion and cuticular hydrocarbons in the stingless bee Melipona quadrifasciata.

    Science.gov (United States)

    Cruz-Landim, C; Ferreira-Caliman, M J; Gracioli-Vitti, L F; Zucchi, R

    2012-04-19

    We investigated whether Melipona quadrifasciata worker mandibular gland secretions contribute directly to their cuticular hydrocarbon profile. The mandibular gland secretion composition and cuticular surface compounds of newly emerged worker bees, nurse bees, and foragers were determined by gas chromatography and mass spectrometry and compared. Both the mandibular gland secretions and the cuticular surface compounds of all worker stages were found to be composed almost exclusively of hydrocarbons. Although the relative proportion of hydrocarbons from the cuticular surface and gland secretion was statistically different, there was a high similarity in the qualitative composition between these structures in all groups of bees.

  9. A cohort study of intra-urban variations in volatile organic compounds and mortality, Toronto, Canada

    International Nuclear Information System (INIS)

    Villeneuve, Paul J.; Jerrett, Michael; Su, Jason; Burnett, Richard T.; Chen, Hong; Brook, Jeffrey; Wheeler, Amanda J.; Cakmak, Sabit; Goldberg, Mark S.

    2013-01-01

    This study investigated associations between long-term exposure to ambient volatile organic compounds (VOCs) and mortality. 58,760 Toronto residents (≥35 years of age) were selected from tax filings and followed from 1982 to 2004. Death information was extracted using record linkage to national mortality data. Land-use regression surfaces for benzene, n-hexane, and total hydrocarbons were generated from sampling campaigns in 2002 and 2004 and assigned to residential addresses in 1982. Cox regression was used to estimate relationships between each VOC and non-accidental, cardiovascular, and cancer mortality. Positive associations were observed for each VOC. In multi-pollutant models the benzene and total hydrocarbon signals were strongest for cancer. The hazard ratio for cancer that corresponded to an increase in the interquartile range of benzene (0.13 μg/m 3 ) was 1.06 (95% CI = 1.02–1.11). Our findings suggest ambient concentrations of VOCs were associated with cancer mortality, and that these exposures did not confound our previously reported associations between NO 2 and cardiovascular mortality. -- Highlights: ► We studied associations between long-term exposure to volatile organic compounds and mortality. ► The study was a population-based cohort of Toronto adults followed for up to 22 years. ► We used land-use regression estimates of benzene, total hydrocarbons and n-hexane. ► Benzene and total hydrocarbons were positively associated with cancer mortality. ► VOCs did not confound associations between NO 2 and cardiovascular mortality. -- Long-term exposure to ambient benzene was associated with non-accidental and cancer causes of death, and did not attenuate associations between NO 2 and cardiovascular mortality

  10. Oak (Quercus frainetto Ten. Honeydew Honey—Approach to Screening of Volatile Organic Composition and Antioxidant Capacity (DPPH and FRAP Assay

    Directory of Open Access Journals (Sweden)

    Igor Jerković

    2010-05-01

    Full Text Available Two samples of oak honeydew honey were investigated. Headspace solid-phase microextraction (HS-SPME combined with GC and GC/MS enabled identification of the most volatile organic headspace compounds being dominated by terpenes(mainly cis- and trans-linalool oxides. The volatile and less-volatile organic composition of the samples was obtained by ultrasonic assisted extraction (USE with two solvents (1:2 (v/v pentane -diethyl ether mixture and dichloromethane followed by GC and GC/MS analysis. Shikimic pathway derivatives are of particular interest with respect to the botanical origin of honey and the most abundant was phenylacetic acid (up to 16.4%. Antiradical activity (DPPH assay of the honeydew samples was 4.5 and 5.1 mmol TEAC/kg. Ultrasonic solvent extracts showed several dozen times higher antiradical capacity in comparison to the honeydew. Antioxidant capacity (FRAP assay of honeydew samples was 4.8 and 16.1 mmol Fe2+/kg, while the solvent mixture extracts showed antioxidant activity of 374.5 and 955.9 Fe2+/kg, respectively, and the dichloromethane extracts 127.3 and 101.5 mmol Fe2+/kg.

  11. In situ vadose zone bioremediation of soil contaminated with nonvolatile hydrocarbons

    International Nuclear Information System (INIS)

    Hogg, D.S.; Burden, R.J.; Riddell, P.J.

    1992-01-01

    In situ bioremediation has been successfully carried out on petroleum hydrocarbon-contaminated soil at a decommissioned bulk storage terminal in New Zealand. The site soils were contaminated mainly with diesel fuel and spent oil at concentrations ranging up to 95,000 mg/kg of total recoverable petroleum hydrocarbons. The in situ remediation system combines an enhanced bioremediation with vapor extraction and is installed almost entirely below grade, thereby allowing above ground activities to continue unimpeded. Laboratory-scale feasibility testing indicated that although appreciable volatilization of low molecular weight components would occur initially, biodegradation would be the primary mechanism by which contaminated soil would be remediated. During the remedial design phase, preliminary field testing was conducted to evaluate the optimum spacing for extraction wells and inlet vents. A pilot-scale system was installed in a 15-m by 35-m area of the site in June 1989 and operated for approximately 1 year. Soil monitoring performed approximately every 3 months indicated an overall reduction in soil petroleum hydrocarbon concentrations of 87% for the period from June 1989 to May 1991

  12. Development changes of cuticular hydrocarbons in Chrysomya rufifacies larvae: potential for determining larval age.

    Science.gov (United States)

    Zhu, G H; Ye, G Y; Hu, C; Xu, X H; Li, K

    2006-12-01

    Age determination is the basis of determining the postmortem interval using necrophagous fly larvae. To explore the potential of using cuticular hydrocarbons for determining the ages of fly larvae, changes of cuticular hydrocarbons in developing larvae of Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae) were investigated using gas chromatography with flame-ionization detection and gas chromatography-mass spectrometry. This study showed that the larvae produced cuticular hydrocarbons typical of insects. Most of the hydrocarbons identified were alkanes with the carbon chain length of 21-31, plus six kinds of alkenes. The hydrocarbon composition of the larvae correlated with age. The statistical results showed that simple peak ratios of n-C29 divided by another eight selected peaks increased significantly with age; their relationships with age could be modelled using exponential or power functions with R(2) close to or > 0.80. These results suggest that cuticular hydrocarbon composition is a useful indicator for determining the age of larval C. rufifacies, especially for post-feeding larvae, which are difficult to differentiate by morphology.

  13. Chemical Compositions of Achillea sivasica: Different Plant Part Volatiles, Enantiomers and Fatty Acids

    Directory of Open Access Journals (Sweden)

    Gülmira Özek

    2018-03-01

    Full Text Available In the present work, Microsteam distillation - Solid phase microextraction (MSD-SPME and hydrodistillation (HD techniques were applied to obtain volatiles from Achillea sivasica, an endemic species from Turkey. GC-FID and GC/MS analysis revealed that 1,8-cineole (22.1% and a -pinene (9.3% were the main constituents of the hydrodistilled flower volatiles. (Z- b -Farnesene (23.9%, decanoic acid (10.1%, b- eudesmol (8.0%, tricosane (7.3% and hexadecanoic acid (7.2% were the main volatiles obtained from flowers by MSD-SPME. The leaf volatiles obtained by HD contained camphor (9.0%, b -pinene (6.9%, 1,8-cineole (6.7%, a -pinene (6.7% and a -bisabolol (6.6% as the main constituents while the leaf volatiles obtained by MSD-SPME technique were rich in (E-geranyl acetone (10.5%, (E- b -ionone (10.3%, camphor (10.2%, 1,8-cineole (9.6%, longiverbenone (7.9%, b -eudesmol (7.5%, isopropyl myristate (6.7% and epi- a -bisabolol (6.4%. The root volatiles were rich in longiverbenone (14.1%, (E-geranyl acetone (9.3%, nonanol (12.1% and decanol (12.5%. The enantiomeric distribution of the major volatile constituents was analyzed by using different b -cyclodextrin chiral columns. (1R-(+- a -Pinene, (1S-(-- b -pinene, (4R-(+-limonene, (1R,3S,5R-(--trans-pinocarveol, (1S,2R,4S-(--borneol, (2S-(-- a -bisabolol were detected as dominant enantiomers. The lipids extracted from the flower and leaf with Folch method and methylated with BF 3 reagent contained common acids: linolenic, linoleic, hexadecanoic acids. Oleic and stearic acids were detected particularly in high amount in the flower lipids

  14. Influence of partial replacement of NaCl with KCl on profiles of volatile compounds in dry-cured bacon during processing.

    Science.gov (United States)

    Wu, Haizhou; Zhuang, Hong; Zhang, Yingyang; Tang, Jing; Yu, Xiang; Long, Men; Wang, Jiamei; Zhang, Jianhao

    2015-04-01

    This study investigated the influence of partial substitution of NaCl with KCl on the formation of volatile compounds in bacons during processing using a purge and trap dynamic headspace GC/MS system. Three substitutions were 0% KCl (I), 40% KCl (II), and 70% KCl (III). The profiles of the volatile compounds significantly changed during processing, particularly during the drying/ripening. At the end of process, the bacons from substitution III formed significantly higher levels of lipid-derived volatiles, such as straight chain aldehydes, hydrocarbons than bacons from substitution I and II, whereas the latter formed higher levels of volatiles from amino acid degradation such as 3-methylbutanal. There were very few differences in volatile formation between 0% and 40% KCl application. These results suggest that K(+) substitution of Na(+) by more than 40% may significantly change profiles of volatiles in finished dry-cured bacons and therefore would result in changes in the product aroma and/or flavour. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. THE VOLATILE COMPOSITION AND ACTIVITY OF COMET 103P/HARTLEY 2 DURING THE EPOXI CLOSEST APPROACH

    International Nuclear Information System (INIS)

    Dello Russo, N.; Vervack, R. J. Jr; Lisse, C. M.; Weaver, H. A.; Kawakita, H.; Kobayashi, H.; Cochran, A. L.; Harris, W. M.; McKay, A. J.; Biver, N.; Bockelee-Morvan, D.; Crovisier, J.

    2011-01-01

    We report time-resolved measurements of the absolute and relative abundances of eight parent volatiles (H 2 O, CH 3 OH, C 2 H 6 , C 2 H 2 , NH 3 , HCN, H 2 CO, and HC 3 N) in the coma of 103P/Hartley 2 on UT 2010 November 4, the date the EPOXI spacecraft made its closest approach to the comet, using high-dispersion infrared spectroscopy with NIRSPEC at the W. M. Keck Observatory. Overall gas and dust production increased by roughly 60% between UT 10:49 and 15:54. Differences in the spatial distributions of species in the coma suggest icy sources of different composition in the nucleus of 103P/Hartley 2. However, differences in the relative abundances of species with time are minor, suggesting either internal compositional heterogeneity in 103P/Hartley 2 is small compared with the diversity of chemistry observed within the comet population, or more significant heterogeneity exists on scales smaller than our spatial resolution. Observations contemporaneous with the EPOXI encounter test how compositional heterogeneity over the surface and the inner coma of a comet manifests itself in remote-sensing observations of the bulk coma.

  16. Effect of a cationic surfactant on the volatilization of PAHs from soil.

    Science.gov (United States)

    Lu, Li; Zhu, Lizhong

    2012-06-01

    Cationic surfactants are common in soils because of their use in daily cosmetic and cleaning products, and their use as a soil amendment for the mitigation and remediation of organic contaminated soils has been proposed. Such surfactant may affect the transfer and fate of organic contaminants in the environment. This study investigated the effect of a cationic surfactant, dodecylpyridinium bromide (DDPB), on the volatilization of polycyclic aromatic hydrocarbons (PAHs) from a paddy soil. The volatilization of PAHs from moist soil amended with different concentrations of DDPB was tested in an open system. The specific effects of DDPB on the liquid-vapor and solid-vapor equilibriums of PAHs were separately investigated in closed systems by headspace analysis. DDPB affects both liquid-vapor and solid-vapor processes of PAHs in soil. At DDPB concentrations below the critical micelle concentration (CMC), movement of PAHs from the bulk solution to the gas-liquid interface appeared to be facilitated by interaction between PAHs and the surfactant monomers adsorbed at the gas-liquid interface, promoting the volatilization of PAHs from solution. However, when DDPB was greater than the CMC, volatilization was inhibited due to the solubilization of PAHs by micelles. On the other hand, the formation of sorbed surfactant significantly inhibited the solid-vapor volatilization of PAHs. The overall effect of the two simultaneous effects of DDPB on liquid-vapor and solid-vapor processes was a decreased volatilization loss of PAHs from soil. Inhibition of PAH volatilization was more significant for the soil with a lower moisture content.

  17. The Composition of Comet C/2012 K1 (PanSTARRS) and the Distribution of Primary Volatile Abundances Among Comets

    Energy Technology Data Exchange (ETDEWEB)

    Roth, Nathan X.; Gibb, Erika L. [Department of Physics and Astronomy, University of Missouri-St. Louis, 503 Benton Hall, One University Blvd., St. Louis, MO 63121 (United States); Bonev, Boncho P.; DiSanti, Michael A.; Mumma, Michael J.; Villanueva, Geronimo L.; Paganini, Lucas, E-mail: nxrq67@mail.umsl.edu [Goddard Center for Astrobiology, NASA Goddard Space Flight Center, Mail Stop 690, Greenbelt, MD 20771 (United States)

    2017-04-01

    On 2014 May 22 and 24 we characterized the volatile composition of the dynamically new Oort cloud comet C/2012 K1 (PanSTARRS) using the long-slit, high resolution ( λ /Δ λ  ≈ 25,000) near-infrared echelle spectrograph (NIRSPEC) at the 10 m Keck II telescope on Maunakea, Hawaii. We detected fluorescent emission from six primary volatiles (H{sub 2}O, HCN, CH{sub 4}, C{sub 2}H{sub 6}, CH{sub 3}OH, and CO). Upper limits were derived for C{sub 2}H{sub 2}, NH{sub 3}, and H{sub 2}CO. We report rotational temperatures, production rates, and mixing ratios (relative to water). Compared with median abundance ratios for primary volatiles in other sampled Oort cloud comets, trace gas abundance ratios in C/2012 K1 (PanSTARRS) for CO and HCN are consistent, but CH{sub 3}OH and C{sub 2}H{sub 6} are enriched while H{sub 2}CO, CH{sub 4}, and possibly C{sub 2}H{sub 2} are depleted. When placed in context with comets observed in the near-infrared to date, the data suggest a continuous distribution of abundances of some organic volatiles (HCN, C{sub 2}H{sub 6}, CH{sub 3}OH, CH{sub 4}) among the comet population. The level of “enrichment” or “depletion” in a given comet does not necessarily correlate across all molecules sampled, suggesting that chemical diversity among comets may be more complex than the simple organics-enriched, organics-normal, and organics-depleted framework.

  18. Composition of the earth's upper mantle. II - Volatile trace elements in ultramafic xenoliths

    Science.gov (United States)

    Morgan, J. W.; Wandless, G. A.; Petrie, R. K.; Irving, A. J.

    1980-01-01

    Radiochemical neutron activation analysis was used to determine the nine volatile elements Ag, Bi, Cd, In, Sb, Se, Te, Tl, and Zn in 19 ultramafic rocks, consisting mainly of spinel and garnet lherzolites. A sheared garnet lherzolite, PHN 1611, may approximate undepleted mantle material and tends to have a higher volatile element content than the depleted mantle material represented by spinel lherzolites. Comparisons of continental basalts with PHN 1611 and of oceanic ridge basalts with spinel lherzolites show similar basalt: source material partition factors for eight of the nine volatile elements, Sb being the exception. The strong depletion of Te and Se in the mantle, relative to lithophile elements of similar volatility, suggests that 97% of the earth's S, Se and Te may be in the outer core.

  19. Influence of the yeast autolysates addition on the volatile compounds of sparkling white wines

    Directory of Open Access Journals (Sweden)

    Pérez-Magariño Silvia

    2014-01-01

    Full Text Available During sparkling wine aging, different compounds such as polysaccharides can be released due to yeast autolysis that can cause important changes in wine composition. Yeast autolysis is a slow natural process that takes long time, and the addition of some products could improve the quality of these wines. The aim of this work was to study the effect of the addition of several commercial yeast autolysates on the volatile composition of white sparkling wines (Godello and Verdejo, and aged on lees for 9 months. The discriminant analyses indicated that the sparkling wines treated with PCP2 showed the highest differences in the volatile composition of both sparkling wines studied, being the ethyl esters, terpenes, decanoic acid and some alcohols, the compounds that were affected in a greater extent. This fact could be due to PCP2 presenting the highest mannoprotein percentage that can interact with volatile compounds, modulating their volatility and perception.

  20. Graphene and poly(methyl methacrylate) composite laminates on flexible substrates for volatile organic compound detection

    Science.gov (United States)

    Rattanabut, Chanoknan; Wongwiriyapan, Winadda; Muangrat, Worawut; Bunjongpru, Win; Phonyiem, Mayuree; Song, Young Jae

    2018-04-01

    In this paper, we present a gas sensor for volatile organic compound (VOC) detection based on graphene and poly(methyl methacrylate) (GR/PMMA) composite laminates fabricated using CVD-grown graphene. Graphene was transferred to a poly(ethylene terephthalate) (PET) substrate by PMMA-supported wet transfer process without PMMA removal in order to achieve the deposition of GR/PMMA composite laminates on PET. The GR/PMMA and graphene sensors show completely different sensitivities to VOC vapors. The GR/PMMA and graphene sensors showed the highest sensitivities to dichloromethane (DCM). The response of the GR/PMMA sensor to DCM was 3 times higher than that of the graphene sensor but the GR/PMMA sensor hardly responded to acetone, chloroform, or benzene. The sensing mechanism of the graphene sensor can be based on the dielectric constant of VOCs, the size of VOC molecule, and electron hopping effects on defect graphene, while that of the GR/PMMA sensor can be explained in terms of the polymer swelling owing to the Hansen solubility parameter.

  1. Comparative Analysis of Flower Volatiles from Nine Citrus at Three Blooming Stages

    Directory of Open Access Journals (Sweden)

    Muhammad Azam

    2013-11-01

    Full Text Available Volatiles from flowers at three blooming stages of nine citrus cultivars were analyzed by headspace-solid phase microextraction (HS-SPME-GC-MS. Up to 110 volatiles were detected, with 42 tentatively identified from citrus flowers for the first time. Highest amounts of volatiles were present in fully opened flowers of most citrus, except for pomelos. All cultivars were characterized by a high percentage of either oxygenated monoterpenes or monoterpene hydrocarbons, and the presence of a high percentage of nitrogen containing compounds was also observed. Flower volatiles varied qualitatively and quantitatively among citrus types during blooming. Limonene was the most abundant flower volatile only in citrons; α-citral and β-citral ranked 2nd and 3rd only for Bergamot, and unopened flowers of Ponkan had a higher amount of linalool and β-pinene while much lower amount of γ-terpinene and p-cymene than Satsuma. Taking the average of all cultivars, linalool and limonene were the top two volatiles for all blooming stages; β-pinene ranked 3rd in unopened flowers, while indole ranked 3rd for half opened and fully opened flower volatiles. As flowers bloomed, methyl anthranilate increased while 2-hexenal and p-cymene decreased. In some cases, a volatile could be high in both unopened and fully opened flowers but low in half opened ones. Through multivariate analysis, the nine citrus cultivars were clustered into three groups, consistent with the three true citrus types. Furthermore, an influence of blooming stages on clustering was observed, especially with hybrids Satsuma and Huyou. Altogether, it was suggested that flower volatiles can be suitable markers for revealing the genetic relationships between citrus cultivars but the same blooming stage needs to be strictly controlled.

  2. Thermodynamic analysis for syngas production from volatiles released in waste tire pyrolysis

    International Nuclear Information System (INIS)

    Martínez, Juan Daniel; Murillo, Ramón; García, Tomás; Arauzo, Inmaculada

    2014-01-01

    Highlights: • Pyrolysis experiments have been conducted in a continuous auger reactor. • Pyrolysis temperature influence on composition of both volatiles and char was studied. • A process for syngas production has been proposed from the volatiles. • Equivalence ratio down to 0.4 is a practical limit for syngas production. • The results provide essential data prior to perform any experimental campaign. - Abstract: This paper shows the maximum limit on syngas composition obtained from volatiles released in waste tire pyrolysis when they are submitted to an air–steam partial oxidation process. Thus, from mass and energy balances and a stoichiometric equilibrium model, syngas composition and reaction temperature as well as some process parameters were predicted by varying both the equivalence ratio (ER) and the steam to fuel ratio (SF). In addition, pyrolysis experiments were performed using a continuous auger reactor, and the influence of pyrolysis temperature on composition of both volatiles and char was studied. Consequently, the resulting syngas characteristics were correlated with the pyrolysis temperature. The stoichiometric equilibrium model showed that an ER down to 0.4 is a practical limit to perform the air–steam partial oxidation process. When the process is carried out only with air, volatiles obtained at high pyrolysis temperature lead to lower reaction temperature and higher LHV of syngas in comparison with those found at low pyrolysis temperature. The H 2 production is favored between 0.20 and 0.40 of ER and seems to be more influenced by the H/C ratio than by the water gas-shift reaction. On the other hand, the steam addition shows a more notable effect on the H 2 production for volatiles obtained at the highest pyrolysis temperature (600 °C) in agreement with the lower reaction temperature under these experimental conditions. This thermodynamic analysis provides essential data on the optimization of syngas production from volatiles

  3. Estimation of the efficiency of hydrocarbon mineralization in soil by measuring CO2-emission and variations in the isotope composition of carbon dioxide

    Science.gov (United States)

    Dubrovskaya, Ekaterina; Turkovskaya, Olga

    2010-05-01

    Estimation of the efficiency of hydrocarbon mineralization in soil by measuring CO2-emission and variations in the isotope composition of carbon dioxide E. Dubrovskaya1, O. Turkovskaya1, A. Tiunov2, N. Pozdnyakova1, A. Muratova1 1 - Institute of Biochemistry and Physiology of Plants and Microorganisms, RAS, Saratov, 2 - A.N. Severtsov Institute of Ecology and Evolution, RAS, Moscow, Russian Federation Hydrocarbon mineralization in soil undergoing phytoremediation was investigated in a laboratory experiment by estimating the variation in the 13С/12С ratio in the respired СО2. Hexadecane (HD) was used as a model hydrocarbon pollutant. The polluted soil was planted with winter rye (Secale cereale) inoculated with Azospirillum brasilense strain SR80, which combines the abilities to promote plant growth and to degrade oil hydrocarbon. Each vegetated treatment was accompanied with a corresponding nonvegetated one, and uncontaminated treatments were used as controls. Emission of carbon dioxide, its isotopic composition, and the residual concentration of HD in the soil were examined after two and four weeks. At the beginning of the experiment, the CO2-emission level was higher in the uncontaminated than in the contaminated soil. After two weeks, the quantity of emitted carbon dioxide decreased by about three times and did not change significantly in all uncontaminated treatments. The presence of HD in the soil initially increased CO2 emission, but later the respiration was reduced. During the first two weeks, nonvegetated soil had the highest CO2-emission level. Subsequently, the maximum increase in respiration was recorded in the vegetated contaminated treatments. The isotope composition of plant material determines the isotope composition of soil. The soil used in our experiment had an isotopic signature typical of soils formed by C3 plants (δ13C,-22.4‰). Generally, there was no significant fractionation of the carbon isotopes of the substrates metabolized by the

  4. Differences in volatile composition and sexual morphs in rambutan (Nephelium lappaceum L. flowers and their effect in the Apis mellifera L. (Hymenoptera, Apidae attraction

    Directory of Open Access Journals (Sweden)

    Lorena Aceves-Chong

    2018-01-01

    Full Text Available We studied the volatile composition and sexual morphs of Nephelium lappaceum flowers from two orchards, and investigated the choice behavior of the honey bee, Apis mellifera toward the floral extracts from both locations. Our results showed significant differences in chemical composition and sexual morphs; only the hermaphrodite flowers from the Herradero orchard produced limonene and α-pinene and had longer peduncle and sepal than flowers from the Metapa orchard; on the other hand, the hermaphrodite flowers from the Metapa orchard had longer gynoecium. In the behavioral experiment the extracts from the Herradero orchard seemed to give A. mellifera foragers better cues for orientation to food sources, perhaps due to the presence of limonene and α-pinene, which are absent in the samples from Metapa. Such differences in both orchards could affect pollinator attraction and ultimately seed set and productivity. Keywords: Floral volatiles, Hermaphrodite sex, Morphological traits, Orchards, Plant–insect interactions.

  5. Effect of Exogenous Abscisic Acid and Methyl Jasmonate on Anthocyanin Composition, Fatty Acids, and Volatile Compounds of Cabernet Sauvignon (Vitis vinifera L.) Grape Berries.

    Science.gov (United States)

    Ju, Yan-Lun; Liu, Min; Zhao, Hui; Meng, Jiang-Fei; Fang, Yu-Lin

    2016-10-12

    The anthocyanin composition, fatty acids, and volatile aromas are important for Cabernet Sauvignon grape quality. This study evaluated the effect of exogenous abscisic acid (ABA) and methyl jasmonate (MeJA) on the anthocyanin composition, fatty acids, lipoxygenase activity, and the volatile compounds of Cabernet Sauvignon grape berries. Exogenous ABA and MeJA improved the content of total anthocyanins (TAC) and individual anthocyanins. Lipoxygenase (LOX) activity also increased after treatment. Furthermore, 16 fatty acids were detected. The linoleic acid concentration gradually increased with ABA concentration. The fatty acid content decreased with increasing MeJA concentration and then increased again, with the exception of linoleic acid. After exogenous ABA and MeJA treatment, the C6 aroma content increased significantly. Interestingly, the exogenous ABA and MeJA treatments improved mainly the content of 1-hexanol, hexanal, and 2-heptanol. These results provide insight into the effect of plant hormones on wine grapes, which is useful for grape quality improvement.

  6. Comparison of consecutive harvests versus blending treatments to produce lower alcohol wines from Cabernet Sauvignon grapes: Impact on wine volatile composition and sensory properties.

    Science.gov (United States)

    Schelezki, Olaf J; Šuklje, Katja; Boss, Paul K; Jeffery, David W

    2018-09-01

    This study extends previous work on Cabernet Sauvignon wines of lowered alcohol concentrations produced by pre-fermentatively substituting proportions of juice from an overripe crop with "green harvest wine" or water to adjust initial sugar concentrations. Resulting wines were assessed for their volatile compositions and sensory characteristics to evaluate the suitability of this winemaking approach to managing wine alcohol concentrations in warm viticulture regions. Wines from water or green harvest wine substitution were also compared to wines of similar alcohol content produced from earlier harvested grapes. Implementation of water substitution in particular resulted in minor alterations of wine volatile composition compared to the control, and positive aroma and flavour characteristics were preserved. However, overripe sensory attributes such as 'hotness' and 'port wine' were conserved whereas they were absent in wines of similar alcohol level made from earlier harvested grapes, thereby emphasising the relevance of grape (over)maturity when producing lower alcohol wines. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Effect of Exogenous Abscisic Acid and Methyl Jasmonate on Anthocyanin Composition, Fatty Acids, and Volatile Compounds of Cabernet Sauvignon (Vitis vinifera L. Grape Berries

    Directory of Open Access Journals (Sweden)

    Yan-Lun Ju

    2016-10-01

    Full Text Available The anthocyanin composition, fatty acids, and volatile aromas are important for Cabernet Sauvignon grape quality. This study evaluated the effect of exogenous abscisic acid (ABA and methyl jasmonate (MeJA on the anthocyanin composition, fatty acids, lipoxygenase activity, and the volatile compounds of Cabernet Sauvignon grape berries. Exogenous ABA and MeJA improved the content of total anthocyanins (TAC and individual anthocyanins. Lipoxygenase (LOX activity also increased after treatment. Furthermore, 16 fatty acids were detected. The linoleic acid concentration gradually increased with ABA concentration. The fatty acid content decreased with increasing MeJA concentration and then increased again, with the exception of linoleic acid. After exogenous ABA and MeJA treatment, the C6 aroma content increased significantly. Interestingly, the exogenous ABA and MeJA treatments improved mainly the content of 1-hexanol, hexanal, and 2-heptanol. These results provide insight into the effect of plant hormones on wine grapes, which is useful for grape quality improvement.

  8. Near infra-red chemical species tomography of sprays of volatile hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Hindle, F.P.; Carey, S.J.; Ozanyan, K.B.; McCann, H. [Dept. of Electrical Engineering and Electronics, UMIST, Manchester (United Kingdom); Winterbone, D.E.; Clough, E. [Dept. of Mechanical, Aerospace and Mfg. Engineering, UMIST, Manchester (United Kingdom)

    2002-08-01

    We report an All-Opto-Electronic tomography system that is sensitive to hydrocarbon vapour distribution, or liquid spray distribution, with temporal resolution of over 3000 frames per second. A tomography system comprising 32 channels has been built and tested. For chemical sensitivity to saturated hydrocarbons, we exploit the principle of Near Infra-Red (NIR) absorption at 1700 nm relative to a reference wavelength, using laser diode sources whose technology is based on that of the communications industry. Images are obtained from a laboratory set-up incorporating both gaseous injection and a liquid Gasoline Direct Injection (GDI) system. The performance of a prototype system on a running GDI engine is reported. The difficulty in performing concentration measurements of the gaseous fuel within the liquid spray region is shown, and means to improve this performance are discussed. However, it has been found possible to image the liquid spray cone using attenuation of the reference beam. These images correlate well with other techniques [1]. (orig.) [German] Wir berichten ueber ein optoelektronisches Tomographiesystem zur Bestimmung der Verteilung von Kohlenwasserstoffdaempfen oder von Spraypartikeln, das eine hohe zeitliche Aufloesung von 3000 Aufnahmen pro Sekunde liefert. Ein System mit 32 Kanaelen wurde gebaut und getestet. Um Empfindichkeit auf gesaettigte Kohlenwasserstoffdaempfe zu erzielen, wurde die Absorption im Nahen Infrarot (NIR) bei 1700 nm, bezogen auf die bei einer Referenzwellen-laenge, genutzt. Laserdioden, deren Technologien auch in der Kommunikationstechnik Verwendung finden, kamen zum Einsatz. Von einem Laboraufbau wurden Bilder aufgenommen sowohl bei Injektion von Gas als auch bei Direkteinspritzung fluessigen Brennstoffs (GDI). Wir berichten ueber die Ergebnisse mit dem Prototyp-Messsystem an einem GDI-Motor. Es werden die Schwierigkeiten gezeigt, Messungen der Gaskonzentration innerhalb eines Spraypartikelbereichs durchzufuehren, und

  9. Process to separate alkali metal salts from alkali metal reacted hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, John Howard; Alvare, Javier; Larsen, Dennis; Killpack, Jeff

    2017-06-27

    A process to facilitate gravimetric separation of alkali metal salts, such as alkali metal sulfides and polysulfides, from alkali metal reacted hydrocarbons. The disclosed process is part of a method of upgrading a hydrocarbon feedstock by removing heteroatoms and/or one or more heavy metals from the hydrocarbon feedstock composition. This method reacts the oil feedstock with an alkali metal and an upgradant hydrocarbon. The alkali metal reacts with a portion of the heteroatoms and/or one or more heavy metals to form an inorganic phase containing alkali metal salts and reduced heavy metals, and an upgraded hydrocarbon feedstock. The inorganic phase may be gravimetrically separated from the upgraded hydrocarbon feedstock after mixing at a temperature between about 350.degree. C. to 400.degree. C. for a time period between about 15 minutes and 2 hours.

  10. The reformation of liquid hydrocarbons in an aqueous discharge reactor

    KAUST Repository

    Zhang, Xuming

    2015-04-21

    We present an aqueous discharge reactor for the reformation of liquid hydrocarbons. To increase a dielectric constant of a liquid medium, we added distilled water to iso-octane and n-dodecane. As expected, we found decreased discharge onset voltage and increased discharge power with increased water content. Results using optical emission spectroscopy identified OH radicals and O atoms as the predominant oxidative reactive species with the addition of water. Enriched CH radicals were also visualized, evidencing the existence of cascade carbon-carbon cleavage and dehydrogenation processes in the aqueous discharge. The gaseous product consisted primarily of hydrogen, carbon monoxide, and unsaturated hydrocarbons. The composition of the product was readily adjustable by varying the volume of water added, which demonstrated a significant difference in composition with respect to the tested liquid hydrocarbon. In this study, we found no presence of CO2 emissions or the contamination of the reactor by solid carbon deposition. These findings offer a new approach to the reforming processes of liquid hydrocarbons and provide a novel concept for the design of a practical and compact plasma reformer. © 2015 IOP Publishing Ltd.

  11. Advanced multivariate analysis to assess remediation of hydrocarbons in soils.

    Science.gov (United States)

    Lin, Deborah S; Taylor, Peter; Tibbett, Mark

    2014-10-01

    Accurate monitoring of degradation levels in soils is essential in order to understand and achieve complete degradation of petroleum hydrocarbons in contaminated soils. We aimed to develop the use of multivariate methods for the monitoring of biodegradation of diesel in soils and to determine if diesel contaminated soils could be remediated to a chemical composition similar to that of an uncontaminated soil. An incubation experiment was set up with three contrasting soil types. Each soil was exposed to diesel at varying stages of degradation and then analysed for key hydrocarbons throughout 161 days of incubation. Hydrocarbon distributions were analysed by Principal Coordinate Analysis and similar samples grouped by cluster analysis. Variation and differences between samples were determined using permutational multivariate analysis of variance. It was found that all soils followed trajectories approaching the chemical composition of the unpolluted soil. Some contaminated soils were no longer significantly different to that of uncontaminated soil after 161 days of incubation. The use of cluster analysis allows the assignment of a percentage chemical similarity of a diesel contaminated soil to an uncontaminated soil sample. This will aid in the monitoring of hydrocarbon contaminated sites and the establishment of potential endpoints for successful remediation.

  12. Development of a portable mass spectrometric system for determination of isotopic composition of solid uranium samples using fluorine volatilization

    Science.gov (United States)

    Loge, G.

    1994-09-01

    Using hardware and materials supplied by LANL, a prototype quadrupole mass spectrometer system designed for portable field analysis of isotopic composition of solid uranium samples was assembled and tested. The system contained the capability for fluorine volatilization of solid uranium samples with gas introduction, which was successfully tested and demonstrated using 100 mg samples of U3O8. Determination of precision and accuracy for measuring isotopic composition was performed using isotopic standards. Use with soil samples containing uranium were also attempted. Silicates in the soil forming SiF4 were found to be a kinetic bottleneck to the formation of UF6. This could be avoided by performing some sort of chemical separation as a pre-treatment step, which was demonstrated using nitric acid.

  13. Volatility of source apportioned wintertime organic aerosol in the city of Athens

    Science.gov (United States)

    Louvaris, Evangelos E.; Florou, Kalliopi; Karnezi, Eleni; Papanastasiou, Dimitrios K.; Gkatzelis, Georgios I.; Pandis, Spyros N.

    2017-06-01

    The volatility distribution of ambient organic aerosol (OA) and its components was measured during the winter of 2013 in the city of Athens combining a thermodenuder (TD) and a High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS). Positive Matrix Factorization (PMF) analysis of both the ambient and the thermodenuder AMS-spectra resulted in a four-factor solution for the OA, namely: hydrocarbon-like OA (HOA), biomass burning OA (BBOA), cooking OA (COA), and oxygenated OA (OOA). The thermograms of the four factors were analyzed and the corresponding volatility distributions were estimated using the volatility basis set (VBS). All four factors included compounds with a wide range of effective volatilities from 10 to less than 10-4 μg m-3 at 298 K. Almost 40% of the HOA consisted of low-volatility organic compounds (LVOCs) with the semi-volatile compounds (SVOCs) representing roughly 30%, while the remaining 30% consisted of extremely low volatility organic compounds (ELVOCs). BBOA was more volatile than the HOA factor on average, with 10% ELVOCs, 40% LVOCs, and 50% SVOCs. 10% of the COA consisted of ELVOCs, another 65% LVOCs, and 50% SVOCs. Finally, the OOA was the least volatile factor and included 40% ELVOCs, 25% LVOCs, and 35% SVOCs. Combining the volatility distributions and the O:C ratios of the various factors, we placed our results in the 2D-VBS analysis framework of Donahue et al. (2012). HOA and BBOA are in the expected region but also include an ELVOC component. COA is in similar range as HOA, but on average is half an order of magnitude more volatile. The OOA in these wintertime conditions had a moderate O:C ratio and included both semi-volatile and extremely low volatility components. The above results are sensitive to the assumed values of the effective vaporization enthalpy and the accommodation coefficient. A reduction of the accommodation coefficient by an order of magnitude or the reduction of the vaporization enthalpy by 20 kJ mol-1

  14. Miniaturized test system for soil respiration induced by volatile pollutants

    International Nuclear Information System (INIS)

    Kaufmann, Karin; Chapman, Stephen J.; Campbell, Colin D.; Harms, Hauke; Hoehener, Patrick

    2006-01-01

    A miniaturized method based on 96-well microtitre plates was developed and used to study respiration in pristine and contaminated soils following addition of volatile substrates. Small soil samples were exposed to fuel components, which were volatilized from spatially separate reservoirs of 2,2,4,4,6,8,8-heptamethylnonane (HMN) as an organic carrier. Respiration was determined as CO 2 production by means of a pH-indicator and bicarbonate-containing agar, or as 14 CO 2 evolution from 14 C-labelled substrates. Substrate concentrations inducing maximum microbial activity or inhibition were determined and CO 2 production profiles examined by multivariate analysis. When high concentrations of fuel components were applied, distinction of hydrocarbon exposed soils from unexposed soil was achieved within 6 h of incubation. With low concentrations, adequate distinction was achieved after 24 h, probably as a result of community adaptation. Nutrient limitation was identified with the 14 C method for toluene, and the optimal N and P amendment determined. Further potential applications of this rapid and inexpensive method are outlined. - A new method to study soil respiration is used when volatile organic contaminants are added

  15. Macro-fiscal volatility and the composition of public spending

    Czech Academy of Sciences Publication Activity Database

    Riscado, S. M.; Stančík, Juraj; Välilä, T.

    2011-01-01

    Roč. 32, č. 4 (2011), s. 511-538 ISSN 0143-5671 R&D Projects: GA MŠk LC542 Institutional research plan: CEZ:AV0Z70850503 Keywords : tax volatility * public investment * public consumption Subject RIV: AH - Economics Impact factor: 0.486, year: 2011

  16. Direct hydrocarbon fuel cells

    Science.gov (United States)

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  17. Flavour compounds in tomato fruits: identification of loci and potential pathways affecting volatile composition.

    Science.gov (United States)

    Mathieu, Sandrine; Cin, Valeriano Dal; Fei, Zhangjun; Li, Hua; Bliss, Peter; Taylor, Mark G; Klee, Harry J; Tieman, Denise M

    2009-01-01

    The unique flavour of a tomato fruit is the sum of a complex interaction among sugars, acids, and a large set of volatile compounds. While it is generally acknowledged that the flavour of commercially produced tomatoes is inferior, the biochemical and genetic complexity of the trait has made breeding for improved flavour extremely difficult. The volatiles, in particular, present a major challenge for flavour improvement, being generated from a diverse set of lipid, amino acid, and carotenoid precursors. Very few genes controlling their biosynthesis have been identified. New quantitative trait loci (QTLs) that affect the volatile emissions of red-ripe fruits are described here. A population of introgression lines derived from a cross between the cultivated tomato Solanum lycopersicum and its wild relative, S. habrochaites, was characterized over multiple seasons and locations. A total of 30 QTLs affecting the emission of one or more volatiles were mapped. The data from this mapping project, combined with previously collected data on an IL population derived from a cross between S. lycopersicum and S. pennellii populations, were used to construct a correlational database. A metabolite tree derived from these data provides new insights into the pathways for the synthesis of several of these volatiles. One QTL is a novel locus affecting fruit carotenoid content on chromosome 2. Volatile emissions from this and other lines indicate that the linear and cyclic apocarotenoid volatiles are probably derived from separate carotenoid pools.

  18. Chemically-resolved aerosol volatility measurements from two megacity field studies

    Directory of Open Access Journals (Sweden)

    J. A. Huffman

    2009-09-01

    Full Text Available The volatilities of different chemical species in ambient aerosols are important but remain poorly characterized. The coupling of a recently developed rapid temperature-stepping thermodenuder (TD, operated in the range 54–230°C with a High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS during field studies in two polluted megacities has enabled the first direct characterization of chemically-resolved urban particle volatility. Measurements in Riverside, CA and Mexico City are generally consistent and show ambient nitrate as having the highest volatility of any AMS standard aerosol species while sulfate showed the lowest volatility. Total organic aerosol (OA showed volatility intermediate between nitrate and sulfate, with an evaporation rate of 0.6%·K−1 near ambient temperature, although OA dominates the residual species at the highest temperatures. Different types of OA were characterized with marker ions, diurnal cycles, and positive matrix factorization (PMF and show significant differences in volatility. Reduced hydrocarbon-like OA (HOA, a surrogate for primary OA, POA, oxygenated OA (OOA, a surrogate for secondary OA, SOA, and biomass-burning OA (BBOA separated with PMF were all determined to be semi-volatile. The most aged OOA-1 and its dominant ion, CO2+, consistently exhibited the lowest volatility, with HOA, BBOA, and associated ions for each among the highest. The similar or higher volatility of HOA/POA compared to OOA/SOA contradicts the current representations of OA volatility in most atmospheric models and has important implications for aerosol growth and lifetime. A new technique using the AMS background signal was demonstrated to quantify the fraction of species up to four orders-of-magnitude less volatile than those detectable in the MS mode, which for OA represent ~5% of the non-refractory (NR OA signal. Our results strongly imply that all OA types should be considered

  19. Influence of in situ steam formation by radio frequency heating on thermodesorption of hydrocarbons from contaminated soil.

    Science.gov (United States)

    Roland, Ulf; Bergmann, Sabine; Holzer, Frank; Kopinke, Frank-Dieter

    2010-12-15

    Thermal desorption of a wide spectrum of organic contaminants, initiated by radio frequency (RF) heating, was studied at laboratory and pilot-plant scales for an artificially contaminated soil and for an originally contaminated soil from an industrial site. Up to 100 °C, moderate desorption rates were observed for light aromatics such as toluene, chlorobenzene, and ethylbenzene. Desorption of the less volatile contaminants was greatly enhanced above 100 °C, when fast evaporation of soil-water produced steam for hydrocarbon stripping (steam-distillation, desorption rates increased by more than 1 order of magnitude). For hydrocarbons with low water solubility (e.g., aliphatic hydrocarbons), the temperature increase above 100 °C after desiccation of soil again led to a significant increase of the removal rates, thus showing the impact of hydrocarbon partial pressure. RF heating was shown to be an appropriate option for thermally enhanced soil vapor extraction, leading to efficient cleaning of contaminated soils.

  20. The effect of gas-phase polycyclic aromatic hydrocarbons on the formation and properties of biogenic secondary organic aerosol particles

    Energy Technology Data Exchange (ETDEWEB)

    Zelenyuk, Alla [Pacific Northwest National Laboratory; USA; Imre, Dan G. [Imre Consulting; USA; Wilson, Jacqueline [Pacific Northwest National Laboratory; USA; Bell, David M. [Pacific Northwest National Laboratory; USA; Suski, Kaitlyn J. [Pacific Northwest National Laboratory; USA; Shrivastava, Manish [Pacific Northwest National Laboratory; USA; Beránek, Josef [Pacific Northwest National Laboratory; USA; Alexander, M. Lizabeth [Pacific Northwest National Laboratory; USA; Kramer, Amber L. [Department of Chemistry; Oregon State University; USA; Massey Simonich, Staci L. [Department of Chemistry; Oregon State University; USA; Environmental and Molecular Toxicology; Oregon State University

    2017-01-01

    When secondary organic aerosol (SOA) particles are formed by ozonolysis in the presence of gas-phase polycyclic aromatic hydrocarbons (PAHs), their formation and properties are significantly different from SOA particles formed without PAHs. For all SOA precursors and all PAHs, discussed in this study, the presence of the gas-phase PAHs during SOA formation significantly affects particle mass loadings, composition, growth, evaporation kinetics, and viscosity. SOA particles formed in the presence of PAHs have, as part of their compositions, trapped unreacted PAHs and products of heterogeneous reactions between PAHs and ozone. Compared to ‘pure’ SOA particles, these particles exhibit slower evaporation kinetics, have higher fractions of non-volatile components, like oligomers, and higher viscosities, assuring their longer atmospheric lifetimes. In turn, the increased viscosity and decreased volatility provide a shield that protects PAHs from chemical degradation and evaporation, allowing for the long-range transport of these toxic pollutants. The magnitude of the effect of PAHs on SOA formation is surprisingly large. The presence of PAHs during SOA formation increases mass loadings by factors of two to five, and particle number concentrations, in some cases, by more than a factor of 100. Increases in SOA mass, particle number concentrations, and lifetime have important implications to many atmospheric processes related to climate, weather, visibility, and human health, all of which relate to the interactions between biogenic SOA and anthropogenic PAHs. The synergistic relationship between SOA and PAHs presented here are clearly complex and call for future research to elucidate further the underlying processes and their exact atmospheric implications.

  1. Effect of the partial NaCl substitution by other chloride salts on the volatile profile during the ripening of dry-cured lacón

    Energy Technology Data Exchange (ETDEWEB)

    Dominguez, R.; Munekata, P.E.; Cittadini, A.; Lorenzo, J.M.

    2016-07-01

    The influence of three salting treatments (treatment II: 50% NaCl-50% KCl; III: 45% NaCl-25% KCl-20% CaCl2-10% MgCl2; IV: 30% NaCl-50% KCl-15% CaCl2-5% MgCl2) on the formation of volatile compounds throughout the process was studied and compared to those of a control “lacón” (treatment I: 100% NaCl). There was an intense formation of volatile compounds throughout the processing, particularly during the dry-ripening stage. The most abundant chemical family in all the formulations, in the final product was hydrocarbons followed by aldehydes. The total volatile compound release was more intense in the control “lacóns” (1164 AU×106 ·g–1dry matter) than in “lacóns” from formulations II, III and IV (817–891 AU×106 ·g−1dry matter). The “lacóns” from formulation I showed the highest amounts of aldehydes. The “lacóns” from formulations I and II presented the highest amounts of hydrocarbons. The main conclusion is that the replacement of NaCl produces changes in the volatile profile and could be affect the aroma of “lacón”. (Author)

  2. Endogenous Lunar Volatiles: Insights into the Abundances of Volatiles in the Moon from Lunar Apatite

    Science.gov (United States)

    McCubbin, Francis

    2016-01-01

    At the time of publication of New Views of the Moon, it was thought that the Moon was bone dry with less than about 1 ppb H2O. However in 2007, initial reports at the 38th Lunar and Planetary Science Conference speculated that H-species were present in both apatites and pyroclastic volcanic lunar glasses. These early reports were later confirmed through peer-review, which motivated many subsequent studies on magmatic volatiles in and on the Moon within the last decade. Some of these studies have cast into question the post-Apollo view of lunar formation, the distribution and sources of volatiles in the Earth-Moon system, and the thermal and magmatic evolution of the Moon. The mineral apatite has been one of the pillars of this new field of study, and it will be the primary focus of this abstract. Although apatite has been used both to understand the abundances of volatiles in lunar systems as well as the isotopic compositions of those volatiles, the focus here will be on the abundances of F, Cl, and H2O. This work demonstrates the utility of apatite in advancing our understanding of lunar volatiles, hence apatite should be among the topics covered in the endogenous lunar volatile chapter in NVM II. Truncated ternary plot of apatite X-site occupancy (mol%) from highlands apatite and mare basalt apatite plotted on the relative volatile abundance diagram from. The solid black lines delineate fields of relative abundances of F, Cl, and H2O (on a weight basis) in the melt from which the apatite crystallized. The diagram was constructed using available apatite/melt partitioning data for fluorine, chlorine, and hydroxyl.

  3. Photo-assisted removal of fuel oil hydrocarbons from wood and concrete.

    Science.gov (United States)

    Popova, Inna E; Kozliak, Evguenii I

    2008-08-01

    A novel photo-treatment to decontaminate building structural elements polluted with fuel oil hydrocarbons as a result of spillage and/or a catastrophic flood was examined. A proof-of-concept study evaluating the photocatalytic removal of hydrocarbons (n-hexadecane and fuel oil #2) from contaminated wood (southern yellow pine) and concrete was conducted using scintillation counting (with (14)C-labeled n-hexadecane) and gas chromatography. Contaminated samples were irradiated by UV or fluorescent light in the absence or presence of a photocatalyst, TiO(2). As a result of the treatment, under various scenarios, up to 80-98% of the originally applied n-hexadecane was removed, within a wide range of contaminant concentrations (4-250 mg/g wood). The essential treatment time increased from 1-7 days for low concentrations to several weeks for high concentrations. Mass balance experiments showed that the only product formed from (14)C-labeled n-hexadecane in detectable amounts was (14)CO(2). For low amounts of applied hydrocarbon (4-20 mg/g wood), the overall process rate was limited by the contaminant transport/mobility whereas for high n-hexadecane concentrations (150-250 mg/g, corresponding to 50-80% filling of wood pores), the key factor was the photochemical reaction. Photodegradation experiments conducted with standard heating fuel oil #2 (a representative real-world contaminant) resulted in a significant (up to 80%) photochemical removal of mid-size hydrocarbons (C(13)-C(17)) in 3 weeks whereas heavier hydrocarbons (> C(17)) were not affected; light hydrocarbons (evaporation. These results point toward a promising technique to reclaim wooden and concrete structures contaminated with semi-volatile chemicals.

  4. Determination of molecular structures of aromatic hydrocarbons of crystal fractions of Noriysk crude by a series of luminescent-spectral methods

    Energy Technology Data Exchange (ETDEWEB)

    Ogloblina, A.I.; Alekseyeva, T.A.; Barabadze, Sh.Sh.; Melikadze, L.D.; Teplitskaya, T.A.

    1979-01-01

    The structure of crystalline aromatic hydrocarbons isolated from the high boiling fraction (540-560 degrees) of Noriysk crude was studied using methods of luminescent-spectral analysis. The individual composition of the crystalline aromatic hydrocarbons was analyzed by a combination of fine structure luminescent spectroscopy and spectrofluorimetric methods in frozen matrices using spectra of fluorescence, phosphorescence and excitation of luminescence. The composite method used at 77 K is very effective and allows detailed characteristics of the molar-group composition of complex mixtures of petroleum aromatic hydrocarbons to the point of identification of individual components.

  5. Apatite: A New Tool For Understanding The Temporal Variability Of Magmatic Volatile Contents

    Science.gov (United States)

    Stock, M. J.; Humphreys, M.; Smith, V.; Pyle, D. M.; Isaia, R.

    2015-12-01

    The apatite crystal structure is capable of incorporating H2O, F and Cl, as well as trace CO2 and sulphur. These can be related to parental magma compositions through application of a series of pressure and temperature-dependent exchange reactions (Piccoli and Candela, 1994), permitting apatite crystals to preserve a record of all major volatile species in the melt. Furthermore, due to the general incompatibility of P in other rock-forming minerals, apatite is ubiquitous in igneous systems and often begins crystallising early, such that apatite inclusions within phenocrysts record melt volatile contents throughout magmatic differentiation. In this work, we compare the compositions of apatite inclusions and microphenocrysts with pyroxene-hosted melt inclusions from the Astroni 1 eruption of Campi Flegrei, Italy. These data are coupled with magmatic differentiation models (Gualda et al., 2012), experimental volatile solubility data (Webster et al., 2014) and thermodynamic models of apatite compositional variations (Piccoli and Candela, 1994) to determine a time-series of magmatic volatile evolution in the build-up to eruption. We find that apatite halogen/OH ratios decreased through magmatic differentiation, while melt inclusion F and Cl concentrations increased. Melt inclusion H2O contents are constant at ~2.5 wt%. These data are best explained by volatile-undersaturated differentiation over most of the crystallisation history of the Astroni 1 melt, with melt inclusion H2O contents reset during ascent, due to rapid H diffusion through the phenocryst hosts (Woods et al., 2000). Given the rapid diffusivity of volatiles in apatite (Brenan, 1993), preservation of undersaturated compositions in microphenocrysts suggests that saturation was only achieved a few days to months before eruption and that it may have been the transition into a volatile-saturated state that ultimately triggered eruption. Piccoli and Candela, 1994. Am. J. of Sc., 294, 92-135. Gualda et al., 2012

  6. Volatiles from roasted byproducts of the poultry-processing industry.

    Science.gov (United States)

    Wettasinghe, M; Vasanthan, T; Temelli, F; Swallow, K

    2000-08-01

    Volatiles of roasted chicken breast muscle and byproducts, such as backbones, breastbones, spent bones, and skin, were investigated. Total volatile concentrations ranged from 2030 ppb in the roasted backbones to 4049 ppb in the roasted skin. The major classes of volatile compounds detected in roasted samples were aldehydes (648-1532 ppb) and alcohols (336-1006 ppb). Nitrogen- and/or sulfur-containing compounds were also detected in appreciable quantities (161-706 ppb) in all samples. For all samples, hexanal and 2-methyl-2-buten-1-ol were dominant among the aldehydes and alcohols, respectively. Among the nitrogen- and sulfur-containing compounds, Maillard reaction products, such as tetrahydropyridazines, piperidines, and thiazoles, were the major contributors to the total volatile content in all samples. The composition of volatiles observed in roasted byproducts was markedly different from that of the roasted breast muscle. Therefore, the blending of the byproducts in appropriate proportions or blending of volatile flavor extracts from different byproducts may be necessary to obtain an aroma that mimics roasted chicken aroma.

  7. Synthesis and Characterization of Quaternary Metal Chalcogenide Aerogels for Gas Separation and Volatile Hydrocarbon Adsorption

    KAUST Repository

    Edhaim, Fatimah A.

    2017-01-01

    as sorbents for selective gas separation and volatile organic compounds adsorption. They showed preferential adsorption of polarizable gases (CO2) and organic compounds (toluene). Ion exchange and heavy metal remediation properties have also been demonstrated

  8. Forecasting volatility in Chinese and Hong Kong stock markets.

    OpenAIRE

    Wu, Ming

    2011-01-01

    This paper analyses the forecasting performance of historical volatility models and GARCH-class models of Shenzhen component index, Shanghai composite index and Hang Seng index at weekly and daily frequency under both symmetric and asymmetric loss functions. Under symmetric loss functions exclude Theil-U and HR, results suggest that historical volatility models provide a much better forecast than GARCH-class models both in weekly and daily frequency. Under asymmetric loss functions historical...

  9. Composition of volatile aromatic compounds and minerals of tarhana enriched with cherry laurel (Laurocerasus officinalis).

    Science.gov (United States)

    Temiz, Hasan; Tarakçı, Zekai

    2017-03-01

    Different concentrations of cherry laurel pulp (0, 5, 10, 15 and 20%) were used to produce tarhana samples. Volatile aromatic compounds and minor mineral content were investigated. Volatile aromatic compounds were analyzed by using GC-MS with SPME fiber and minor mineral values were evaluated with inductively coupled plasma optical emission spectrometer. The statistical analysis showed that addition of pulp affected volatile aromatic compounds and minor mineral content significantly. Thirty five volatile aromatic compounds were found in tarhana samples. The octanoic acid from acids, benzaldehyde (CAS) phenylmethanal from aldehydes, 6-methyl-5-hepten-2-one from ketones, octadecane (CAS) n -octadecane form terpenes, ethyl caprylate from esters and benzenemethanol (CAS) benzyl alcohol from alcohols had the highest percentage of volatile aromatic compounds. Tarhana samples were rich source of Mn, Cu and Fe content.

  10. Monitoring in situ biodegradation of hydrocarbons by using stable carbon isotopes

    International Nuclear Information System (INIS)

    Aggarwal, P.K.; Hinchee, R.E.

    1991-01-01

    Spilled or leaked nonhalogenated petroleum hydrocarbons in the soil can generally be metabolized by indigenous, aerobic bacteria. In situ biological degradation of hydrocarbons may be accelerated by supplying inorganic nutrients and/or oxygen. Approaches to monitoring and verifying enhanced in situ biodegradation have included measurements of changes over time in the (a) concentration of hydrocarbons, (b) temperature, (c) number of hydrocarbon-degrading microorganisms, (d) ratio of fast-degrading hydrocarbons (e.g., pristanes or phytanes), and (e) metabolic intermediates. Measurements of oxygen consumption over time and elevated carbon dioxide concentrations in soil gas also have been used as indicators of hydrocarbon degradation. An alternative approach that may help substantiate biodegradation is to measure stable carbon isotope ratios in soil gas CO 2 . Stable carbon isotope ratio analysis is inexpensive and commercially available at many laboratories. Carbon dioxide produced by hydrocarbon degradation may be distinguished from that produced by other processes based on the carbon isotopic compositions characteristic of the source material and/or fractionation accompanying microbial metabolism. Here the authors demonstrate the applicability of the stable isotope technique for monitoring enhanced. aerobic biodegradation of hydrocarbons using data from three locations in the United States

  11. Human skin volatiles: a review.

    Science.gov (United States)

    Dormont, Laurent; Bessière, Jean-Marie; Cohuet, Anna

    2013-05-01

    Odors emitted by human skin are of great interest to biologists in many fields; applications range from forensic studies to diagnostic tools, the design of perfumes and deodorants, and the ecology of blood-sucking insect vectors of human disease. Numerous studies have investigated the chemical composition of skin odors, and various sampling methods have been used for this purpose. The literature shows that the chemical profile of skin volatiles varies greatly among studies, and the use of different sampling procedures is probably responsible for some of these variations. To our knowledge, this is the first review focused on human skin volatile compounds. We detail the different sampling techniques, each with its own set of advantages and disadvantages, which have been used for the collection of skin odors from different parts of the human body. We present the main skin volatile compounds found in these studies, with particular emphasis on the most frequently studied body regions, axillae, hands, and feet. We propose future directions for promising experimental studies on odors from human skin, particularly in relation to the chemical ecology of blood-sucking insects.

  12. Process for conversion of lignin to reformulated hydrocarbon gasoline

    Science.gov (United States)

    Shabtai, Joseph S.; Zmierczak, Wlodzimierz W.; Chornet, Esteban

    1999-09-28

    A process for converting lignin into high-quality reformulated hydrocarbon gasoline compositions in high yields is disclosed. The process is a two-stage, catalytic reaction process that produces a reformulated hydrocarbon gasoline product with a controlled amount of aromatics. In the first stage, a lignin material is subjected to a base-catalyzed depolymerization reaction in the presence of a supercritical alcohol as a reaction medium, to thereby produce a depolymerized lignin product. In the second stage, the depolymerized lignin product is subjected to a sequential two-step hydroprocessing reaction to produce a reformulated hydrocarbon gasoline product. In the first hydroprocessing step, the depolymerized lignin is contacted with a hydrodeoxygenation catalyst to produce a hydrodeoxygenated intermediate product. In the second hydroprocessing step, the hydrodeoxygenated intermediate product is contacted with a hydrocracking/ring hydrogenation catalyst to produce the reformulated hydrocarbon gasoline product which includes various desirable naphthenic and paraffinic compounds.

  13. A volatile topic: Parsing out the details of Earth's formation through experimental metal-silicate partitioning of volatile and moderately volatile elements

    Science.gov (United States)

    Mahan, B. M.; Siebert, J.; Blanchard, I.; Badro, J.; Sossi, P.; Moynier, F.

    2017-12-01

    Volatile and moderately volatile elements display different volatilities and siderophilities, as well as varying sensitivity to thermodynamic controls (X, P, T, fO2) during metal-silicate differentiation. The experimental determination of the metal-silicate partitioning of these elements permits us to evaluate processes controlling the distribution of these elements in Earth. In this work, we have combined metal-silicate partitioning data and results for S, Sn, Zn and Cu, and input these characterizations into Earth formation models. Model parameters such as source material, timing of volatile delivery, fO2 path, and degree of impactor equilibration were varied to encompass an array of possible formation scenarios. These models were then assessed to discern plausible sets of conditions that can produce current observed element-to-element ratios (e.g. S/Zn) in the Earth's present-day mantle, while also satisfying current estimates on the S content of the core, at no more than 2 wt%. The results of our models indicate two modes of accretion that can maintain chondritic element-to-element ratios for the bulk Earth and can arrive at present-day mantle abundances of these elements. The first mode requires the late addition of Earth's entire inventory of these elements (assuming a CI-chondritic composition) and late-stage accretion that is marked by partial equilibration of large impactors. The second, possibly more intuitive mode, requires that Earth accreted - at least initially - from volatile poor material preferentially depleted in S relative to Sn, Zn, and Cu. From a chemical standpoint, this source material is most similar to type I chondrule rich (and S poor) materials (Hewins and Herzberg, 1996; Mahan et al., 2017; Amsellem et al., 2017), such as the metal-bearing carbonaceous chondrites.

  14. Hydrocarbon composition and distribution in a coastal region under influence of oil production in northeast Brazil.

    Science.gov (United States)

    Wagener, Angela de L R; Carreira, Renato S; Hamacher, Claudia; Scofield, Arthur de L; Farias, Cassia O; Cordeiro, Lívia G M S; Luz, Letícia G; Baêta, Aída P; Kalas, Francine A

    2011-08-01

    Waters and sediments from the Potiguar Basin (NE Brazilian coast) were investigated for the presence and nature of polycyclic aromatic hydrocarbons (PAH) and aliphatic hydrocarbons. The region receives treated produced waters through a submarine outfall system serving the industrial district. The total dispersed/dissolved concentrations in the water column ranged from 10-50 ng L(-1) for ∑16PAH and 5-10 μg L(-1) for total aliphatic hydrocarbons. In the sediments, hydrocarbon concentrations were low (0.5-10 ng g(-1)for ∑16PAH and 0.01-5.0 μg g(-1) for total aliphatic hydrocarbons) and were consistent with the low organic carbon content of the local sandy sediments. These data indicate little and/or absence of anthropogenic influence on hydrocarbon distribution in water and sediment. Therefore, the measured values may be taken as background values for the region and can be used as future reference following new developments of the petroleum industry in the Potiguar Basin. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Hydrocarbons (aliphatic and aromatic) in the snow-ice cover in the Arctic

    International Nuclear Information System (INIS)

    Nemirovskaya, I.A.; Novigatsky, A.N.; Kluvitkin, A.A.

    2002-01-01

    This paper presented the concentration and composition of aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) in snow and ice-infested waters in the France-Victoria trough in the northern Barents Sea and in the Mendeleev ridge in the Amerasian basin of the Arctic Ocean. Extreme conditions such as low temperatures, ice sheets and the polar nights render the arctic environment susceptible to oil spills. Hydrocarbons found in these northern seas experience significant transformations. In order to determine the sources, pathways and transformations of the pollutants, it is necessary to know their origin. Hydrocarbon distributions is determined mostly by natural hydrobiological and geochemical conditions. The regularity of migration is determined by natural factors such as formation and circulation of air and ice drift. There is evidence suggesting that the hydrocarbons come from pyrogenic sources. It was noted that hydrocarbons could be degraded even at low temperatures. 17 refs., 1 tab

  16. Volatile Short-chain Chlorinated Hydrocarbons in the Groundwater of the City of Zagreb

    OpenAIRE

    Marijanović-Rajčić, M.; Senta, A.

    2008-01-01

    The aim of the study was to assess the quality of the groundwater sampled from private wells and the public water-supply system in terms of estimating the contamination caused by short-chain chlorinated hydrocarbons, as well as to estimate the exposure of the citizens dwelling in different suburbs to these pollutants of their drinking water (Fig. 1). The aim of the study was also to determine which suburb is supplied through the public water-supply system with water originating from the Sašna...

  17. Volatile halogenated hydrocarbons over the western Pacific between 43° and 4°N

    Science.gov (United States)

    Quack, Birgit; Suess, Erwin

    1999-01-01

    A spectrum of halogenated hydrocarbon compounds in marine air masses were surveyed over an area in the western Pacific between 43°N, 150°E and 4°N, 113°E in September 1994. The ship's track between northern Japan and Singapore traversed three climatic zones of the northern hemisphere. Recently polluted air, clean marine air derived from the central Pacific Ocean from different latitudes, and marine air from the Indonesian archipelago were collected. Tetrachloroethene and trichloroethene of anthropogenic origin, brominated halocarbons as tribromomethane, dibromochloromethane and bromodichloromethane of anthropogenic and natural sources, and other trace gases were measured in the air samples. Very sparse data on the distribution of these compounds exist for the western Pacific atmosphere. The distribution patterns of the compounds were related to synoptic-scale meteorology, spatial conditions, and origin of the air masses. Anthropogenic and natural sources for both chlorinated and brominated substances were identified. Tetrachloroethene and trichloroethene concentrations and their ratios identify anthropogenic sources. Their mixing ratios were quite low compared to previously published data. They are in agreement with expected low concentrations of photochemically active substances during autumn, with an overall decrease in concentrations toward lower latitudes, and with a decrease of emissions during recent years. Strong evidence for a natural source of trichloroethene was discovered in the tropical region. The concentrations of naturally released brominated species were high compared to other measurements over the Pacific. Gradients toward the coasts and elevated concentrations in air masses influenced by coastal emissions point to significant coastal sources of these compounds. The trace gas composition of anthropogenic and natural compounds clearly identified the air masses which were traversed during the cruise.

  18. Evaluation of environmental samples containing heavy hydrocarbon components in environmental forensic investigations

    Energy Technology Data Exchange (ETDEWEB)

    Raia, J.C.; Blakley, C.R.; Fuex, A.N.; Villalanti, D.C.; Fahrenthold, P.D. [Triton Anal Corp, Houston, TX (United States)

    2004-03-01

    This article presents a procedure to evaluate and characterize environmental samples containing mixtures of hydrocarbons over a wide boiling range of materials that include fuels and other products used in commerce. The range of the method extends to the higher boiling and heavier molecular weight hydrocarbon products in the range of motor oil, bunker fuel, and heavier residue materials. The procedure uses the analytical laboratory technique of high-temperature simulated distillation along with mathematical regression of the analytical data to estimate the relative contribution of individual products in mixtures of hydrocarbons present in environmental samples. An analytical technique to determine hydrocarbon-type distributions by gas chromatography-mass spectrometry with nitric oxide ionization spectrometry evaluation is also presented. This type of analysis allows complex hydrocarbon mixtures to be classified by their chemical composition, or types of hydrocarbons that include paraffins, cycloparaffins, monoaromatics, and polycyclic aromatic hydrocarbons. Characteristic hydrocarbon patterns for example, in the relative distribution of polycyclic aromatic hydrocarbons are valuable for determining the potential origin of materials present in environmental samples. These methods provide quantitative data for hydrocarbon components in mixtures as a function of boiling range and 'hydrocarbon fingerprints' of the types of materials present. This information is valuable in assessing environmental impacts of hydrocarbons at contaminated sites and establishing the liabilities and cost allocations for responsible parties.

  19. Fennel (Foeniculum vulgare Mill. subsp. piperitum) florets, a traditional culinary spice in Italy: evaluation of phenolics and volatiles in local populations, and comparison with the composition of other plant parts.

    Science.gov (United States)

    Ferioli, Federico; Giambanelli, Elisa; D'Antuono, L Filippo

    2017-12-01

    Wild fennel (Foeniculum vulgare Mill. subsp. piperitum) florets are used as a typical spice in central and southern Italy. Although fennel (Foeniculum vulgare Mill.), belonging to the Apiaceae (syn. Umbelliferae) family, is a well-known vegetable and aromatic plant, whose main phytochemical compounds have been extensively analysed and investigated as flavouring agents and for their putative health promoting functions, its florets have not been specifically considered up to now. Therefore, the volatile and phenolic composition of florets from an Italian wild fennel crop was determined at different developmental stages, and compared to that of leaves and fruits. Moreover, florets of nine Italian wild fennel populations of different geographical origin from northern-central Italy were also analysed. The total phenolic amount increased from leaves to florets, reaching its highest value in early florets, at 58 012 mg kg -1 of dry matter (DM), then constantly decreased in fruits. In florets of wild populations, phenolics ranged from 6666 to 43 368 mg kg -1 DM. The total amount of volatile compounds was more than twice higher in florets (21 449 mg kg -1 DM) than in leaves (10 470 mg kg -1 DM), reaching its highest value in fruits (50 533 mg kg -1 DM). Estragole and trans-anethole were the main compounds of the volatile fraction. Total volatiles ranged from 24 367 to 60 468 mg kg -1 DM in florets of local populations. Significant changes in the total amount and profile of both phenolic and volatile compounds occurred during plant development. The consistent increase of estragole at later developmental stages supported the claim of different sensory properties of florets and fruits. Geographical origin significantly affected phenolic and volatile composition of wild fennel florets. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  20. Absorbent agents for clean-up of liquid hydrocarbons

    International Nuclear Information System (INIS)

    Waldmann, J.J.

    1993-01-01

    A method is described for absorbing liquid hydrocarbon from a liquid hydrocarbon-contaminated substrate comprising applying to said contaminated substrate an effective amount of a chemical absorbent composition of formula: A m B n C p wherein A m is an acid leached bentonite in a form of hydrous silicate of alumina modified by a hydrophobic alkyl (C 12 -C 24 ) amine which has been double protonized by an aliphatic acid with C 1 -C 18 carbon atoms in which m = 0 to 100% by weight of the composition; B n is a modified aminoplast resin comprised of cyanoguanidine-melamine-urea-formaldehyde in a foam form in which n is 0 to 100% by weight; and C p is a siliceous support-modified hydrophobic material in which p is 0 to 100% by weight; provided that at least one of m and n is a positive numerical value

  1. Intermediate Volatility Organic Compound Emissions from On-Road Gasoline Vehicles and Small Off-Road Gasoline Engines.

    Science.gov (United States)

    Zhao, Yunliang; Nguyen, Ngoc T; Presto, Albert A; Hennigan, Christopher J; May, Andrew A; Robinson, Allen L

    2016-04-19

    Dynamometer experiments were conducted to characterize the intermediate volatility organic compound (IVOC) emissions from a fleet of on-road gasoline vehicles and small off-road gasoline engines. IVOCs were quantified through gas chromatography/mass spectrometry analysis of adsorbent samples collected from a constant volume sampler. The dominant fraction (>80%, on average) of IVOCs could not be resolved on a molecular level. These unspeciated IVOCs were quantified as two chemical classes (unspeciated branched alkanes and cyclic compounds) in 11 retention-time-based bins. IVOC emission factors (mg kg-fuel(-1)) from on-road vehicles varied widely from vehicle to vehicle, but showed a general trend of lower emissions for newer vehicles that met more stringent emission standards. IVOC emission factors for 2-stroke off-road engines were substantially higher than 4-stroke off-road engines and on-road vehicles. Despite large variations in the magnitude of emissions, the IVOC volatility distribution and chemical characteristics were consistent across all tests and IVOC emissions were strongly correlated with nonmethane hydrocarbons (NMHCs), primary organic aerosol and speciated IVOCs. Although IVOC emissions only correspond to approximately 4% of NMHC emissions from on-road vehicles over the cold-start unified cycle, they are estimated to produce as much or more SOA than single-ring aromatics. Our results clearly demonstrate that IVOCs from gasoline engines are an important class of SOA precursors and provide observational constraints on IVOC emission factors and chemical composition to facilitate their inclusion into atmospheric chemistry models.

  2. Mathematical modelling on transport of petroleum hydrocarbons

    Indian Academy of Sciences (India)

    A brief theory has been included on the composition and transport of petroleum hydrocarbons following an onshore oil spill in order to demonstrate the level of complexity associated with the LNAPL dissolution mass transfer even in a classical porous medium. However, such studies in saturated fractured rocks are highly ...

  3. Metal-organic molecular device for non-volatile memory storage

    International Nuclear Information System (INIS)

    Radha, B.; Sagade, Abhay A.; Kulkarni, G. U.

    2014-01-01

    Non-volatile memory devices have been of immense research interest for their use in active memory storage in powered off-state of electronic chips. In literature, various molecules and metal compounds have been investigated in this regard. Molecular memory devices are particularly attractive as they offer the ease of storing multiple memory states in a unique way and also represent ubiquitous choice for miniaturized devices. However, molecules are fragile and thus the device breakdown at nominal voltages during repeated cycles hinders their practical applicability. Here, in this report, a synergetic combination of an organic molecule and an inorganic metal, i.e., a metal-organic complex, namely, palladium hexadecylthiolate is investigated for memory device characteristics. Palladium hexadecylthiolate following partial thermolysis is converted to a molecular nanocomposite of Pd(II), Pd(0), and long chain hydrocarbons, which is shown to exhibit non-volatile memory characteristics with exceptional stability and retention. The devices are all solution-processed and the memory action stems from filament formation across the pre-formed cracks in the nanocomposite film.

  4. Volatile components of vine leaves from two Portuguese grape varieties (Vitis vinifera L.), Touriga Nacional and Tinta Roriz, analysed by solid-phase microextraction.

    Science.gov (United States)

    Fernandes, Bruno; Correia, Ana C; Cosme, Fernanda; Nunes, Fernando M; Jordão, António M

    2015-01-01

    The purpose of this work was to study the volatile composition of vine leaves and vine leaf infusion prepared from vine leaves collected at 30 and 60 days after grape harvest of two Vitis vinifera L. species. Eighteen volatile compounds were identified by gas chromatography-mass spectrometry in vine leaves and in vine leaf infusions. It was observed that the volatile compounds present in vine leaves are dependent on the time of harvest, with benzaldehyde being the major volatile present in vine leaves collected at 30 days after harvesting. There are significant differences in the volatile composition of the leaves from the two grape cultivars, especially in the sample collected at 60 days after grape harvest. This is not reflected in the volatile composition of the vine leaf infusion made from this two cultivars, the more important being the harvesting date for the volatile profile of vine leaf infusion than the vine leaves grape cultivar.

  5. A Green Protocol for Microwave-Assisted Extraction of Volatile Oil Terpenes from Pterodon emarginatus Vogel. (Fabaceae

    Directory of Open Access Journals (Sweden)

    Giuliana M. Vila Verde

    2018-03-01

    Full Text Available Microwave-assisted extraction of volatile oils (MAE potentially offers a more efficient and bio-sustainable method than conventional extraction by Clevenger apparatus (CE. This study aimed to optimise the MAE of the volatile oil from Pterodon emarginatus fruits and characterise the volatile compounds. A 23 full-factorial central composite design and response surface methodology were used to evaluate the effects of time (min, moisture (% and microwave power (W on the extraction yield. The process optimisation was based on the desirability function approach. The reaction time and moisture conditions were standardised in these analyses. The volatile oil composition was analysed by Gas Chromatography/Mass Spectrometry (GC/MS in order to compare techniques extractions influences. Microwave irradiation showed excellent performance for extraction of the volatile oil from Pterodon emarginatus and there were some advantages in compare to conventional method with respect to the time (14 times, energy (6 times, reagents amounts and waste formation. About chemical composition presents significant differences with the type of extraction. Caryophyllene (25.65% and trans-α-bisabolol (6.24% were identified as major components in MAE sample while caryophyllene (6.75% and γ-elemene (7.02% are the components with higher relative percentage in CE samples. The microwaves assisted process shown an increase of economic interested compounds present in volatile oil.

  6. Formalization of hydrocarbon conversion scheme of catalytic cracking for mathematical model development

    Science.gov (United States)

    Nazarova, G.; Ivashkina, E.; Ivanchina, E.; Kiseleva, S.; Stebeneva, V.

    2015-11-01

    The issue of improving the energy and resource efficiency of advanced petroleum processing can be solved by the development of adequate mathematical model based on physical and chemical regularities of process reactions with a high predictive potential in the advanced petroleum refining. In this work, the development of formalized hydrocarbon conversion scheme of catalytic cracking was performed using thermodynamic parameters of reaction defined by the Density Functional Theory. The list of reaction was compiled according to the results of feedstock structural-group composition definition, which was done by the n-d-m-method, the Hazelvuda method, qualitative composition of feedstock defined by gas chromatography-mass spectrometry and individual composition of catalytic cracking gasoline fraction. Formalized hydrocarbon conversion scheme of catalytic cracking will become the basis for the development of the catalytic cracking kinetic model.

  7. Effect of smoking on Polycyclic Aromatic Hydrocarbons (PAHS ...

    African Journals Online (AJOL)

    The effects of smoking on proximate composition, energy values and concentrations of polycyclic aromatic hydrocarbons (PAHs) were studied in raw and smoked samples of catfish (Clarias gariepinus) and tilapia (Oreochromis niloticus). Crude protein was higher in the tilapia sample for both raw and smoked samples.

  8. Hydrocarbon conversion with cracking catalyst having co-combustion promoters lanthanum and iron

    International Nuclear Information System (INIS)

    Csicsery, S.M.

    1979-01-01

    A composition useful in hydrocarbon conversion processes such as catalytic cracking comprises 0.05 to 10 weight percent lanthanum associated with a refractory support. The composition may also include 0.02 to 10 weight percent iron. The refractory support is a zeolitic crystalline aluminosilicate

  9. Removal of hydrocarbon from refinery tank bottom sludge employing microbial culture.

    Science.gov (United States)

    Saikia, Rashmi Rekha; Deka, Suresh

    2013-12-01

    Accumulation of oily sludge is becoming a serious environmental threat, and there has not been much work reported for the removal of hydrocarbon from refinery tank bottom sludge. Effort has been made in this study to investigate the removal of hydrocarbon from refinery sludge by isolated biosurfactant-producing Pseudomonas aeruginosa RS29 strain and explore the biosurfactant for its composition and stability. Laboratory investigation was carried out with this strain to observe its efficacy of removing hydrocarbon from refinery sludge employing whole bacterial culture and culture supernatant to various concentrations of sand-sludge mixture. Removal of hydrocarbon was recorded after 20 days. Analysis of the produced biosurfactant was carried out to get the idea about its stability and composition. The strain could remove up to 85 ± 3 and 55 ± 4.5 % of hydrocarbon from refinery sludge when whole bacterial culture and culture supernatant were used, respectively. Maximum surface tension reduction (26.3 mN m(-1)) was achieved with the strain in just 24 h of time. Emulsification index (E24) was recorded as 100 and 80 % with crude oil and n-hexadecane, respectively. The biosurfactant was confirmed as rhamnolipid containing C8 and C10 fatty acid components and having more mono-rhamnolipid congeners than the di-rhamnolipid ones. The biosurfactant was stable up to 121 °C, pH 2-10, and up to a salinity value of 2-10 % w/v. To our knowledge, this is the first report showing the potentiality of a native strain from the northeast region of India for the efficient removal of hydrocarbon from refinery sludge.

  10. Development of a portable mass spectrometric system for determination of isotopic composition of solid uranium samples using fluorine volatilization. Final report

    International Nuclear Information System (INIS)

    Loge, G.

    1994-01-01

    Using hardware and materials supplied by LANL, a prototype quadrupole mass spectrometer system designed for portable field analysis of isotopic composition of solid uranium samples was assembled and tested. The system contained the capability for fluorine volatilization of solid uranium samples with gas introduction, which was successfully tested and demonstrated using 100 mg samples of U 3 O 8 . Determination of precision and accuracy for measuring isotopic composition was performed using isotopic standards. Use with soil samples containing uranium were also attempted. Silicates in the soil forming SiF 4 were found to be a kinetic bottleneck to the formation of UF 6 . This could be avoided by performing some sort of chemical separation as a pre-treatment step, which was demonstrated using nitric acid

  11. Real-time drilling mud gas monitoring for qualitative evaluation of hydrocarbon gas composition during deep sea drilling in the Nankai Trough Kumano Basin.

    Science.gov (United States)

    Hammerschmidt, Sebastian B; Wiersberg, Thomas; Heuer, Verena B; Wendt, Jenny; Erzinger, Jörg; Kopf, Achim

    2014-01-01

    Integrated Ocean Drilling Program Expedition 338 was the second scientific expedition with D/V Chikyu during which riser drilling was conducted as part of the Nankai Trough Seismogenic Zone Experiment. Riser drilling enabled sampling and real-time monitoring of drilling mud gas with an onboard scientific drilling mud gas monitoring system ("SciGas"). A second, independent system was provided by Geoservices, a commercial mud logging service. Both systems allowed the determination of (non-) hydrocarbon gas, while the SciGas system also monitored the methane carbon isotope ratio (δ(13)CCH4). The hydrocarbon gas composition was predominated by methane (> 1%), while ethane and propane were up to two orders of magnitude lower. δ(13)CCH4 values suggested an onset of thermogenic gas not earlier than 1600 meter below seafloor. This study aims on evaluating the onboard data and subsequent geological interpretations by conducting shorebased analyses of drilling mud gas samples. During shipboard monitoring of drilling mud gas the SciGas and Geoservices systems recorded up to 8.64% and 16.4% methane, respectively. Ethane and propane concentrations reached up to 0.03 and 0.013%, respectively, in the SciGas system, but 0.09% and 0.23% in the Geoservices data. Shorebased analyses of discrete samples by gas chromatography showed a gas composition with ~0.01 to 1.04% methane, 2 - 18 ppmv ethane, and 2 - 4 ppmv propane. Quadruple mass spectrometry yielded similar results for methane (0.04 to 4.98%). With δD values between -171‰ and -164‰, the stable hydrogen isotopic composition of methane showed little downhole variability. Although the two independent mud gas monitoring systems and shorebased analysis of discrete gas sample yielded different absolute concentrations they all agree well with respect to downhole variations of hydrocarbon gases. The data point to predominantly biogenic methane sources but suggest some contribution from thermogenic sources at depth, probably due

  12. Space-weathering processes and products on volatile-rich asteroids

    Science.gov (United States)

    Britt, D.; Schelling, P.; Consolmagno, G.; Bradley, T.

    2014-07-01

    recombine with available solar-wind-implanted hydrogen to form trace amounts of water and OH. Mineral decomposition can be thought of as the first stage of space weathering. It produces weathered surfaces somewhat depleted in volatile elements, creates a predictable set of minor or trace minerals, and leaves the surfaces with catalytic species, primarily npFe0. However, a second stage of further reactions and weathering depends upon the presence of ''feed-stock'' components that can participate in catalyzed chemical reactions on exposed surfaces. For volatile-rich small bodies, the available materials are not only silicates, but a volatile feedstock that can include water, carbon monoxide, ammonia, to name a few. Thermodynamically-driven decomposition of silicates will produce trace amounts of npFe0 which are ideal sites for Fischer-Tropsch type (FTT) catalytic reactions that can produce organics in situ on the asteroids including alkanes, polyaromatic hydrocarbons, and amino acids (J.E. Elsila, 2012, MAPS 47). The mix and range of products depends on the composition and morphology of the mineral surface, energy inputs produced by the micrometeorite impacts or other processes, and the composition of the input volatile feedstock. FFT reactions generate long-chain carbon compounds and amino acids. Secondary reactions that generate more complex carbon compounds and amino acids are likely to occur as the organic material matures. Weathering maturity can be thought of as a function of the abundance and diversity of the weathering products. Since the npFe0 is not destroyed in the reaction, continued micrometeorite bombardment would result in continuing processing and recombination of the existing organic feedstock. More weathering would result in progressively longer-chain carbon compounds as well as more complex and diverse amino acids, and eventually the kerogen-like insoluble-organic matter that forms a large fraction of carbonaceous meteorites. This insight has several major

  13. Volatilization and trapping of ruthenium during calcination of nitric acid solutions

    International Nuclear Information System (INIS)

    Klein, M.; Weyers, C.; Goossens, W.R.A.; Smet, M. de; Trine, J.

    1983-01-01

    Solid radioactive aerosols and semi-volatile fission products e.g. Ru, Cs, Sb are generated during high level liquid waste calcination and vitrification processes. The retention of Ruthenium was studied because of its strong tendency to form volatile compounds in oxidative media. Since RuO 4 was the suspected form for high temperature processes, the study was carried out on the behaviour of RuO 4 and its retention on adsorbants and catalysts for various gas compositions. The behaviour of volatilized Ru species obtained by calcination of nitrosyl Ru compounds was then compared with the RuO 4 case

  14. Siderophile Volatile Element Partitioning during Core Formation.

    Science.gov (United States)

    Loroch, D. C.; Hackler, S.; Rohrbach, A.; Klemme, S.

    2017-12-01

    Since the nineteen sixties it is known, that the Earth's mantle is depleted relative to CI chondrite in numerous elements as a result of accretion and core-mantle differentiation. Additionally, if we take the chondritic composition as the initial solar nebular element abundances, the Earth lacks 85 % of K and up to 98 % of other volatiles. However one potentially very important group of elements has received considerably less attention in this context and these elements are the siderophile but volatile elements (SVEs). SVEs perhaps provide important information regarding the timing of volatile delivery to Earth. Especially for the SVEs the partitioning between metal melt and silicate melt (Dmetal/silicate) at core formation conditions is poorly constrained, never the less they are very important for most of the core formation models. This study is producing new metal-silicate partitioning data for a wide range of SVEs (S, Se, Te, Tl, Ag, As, Au, Cd, Bi, Pb, Sn, Cu, Ge, Zn, In and Ga) with a focus on the P, T and fO2dependencies. The initial hypothesis that we are aiming to test uses the accretion of major portions of volatile elements while the core formation was still active. The key points of this study are: - What are the effects of P, T and fO2 on SVE metal-silicate partioning? - What is the effect of compositional complexity on SVE metal-silicate partioning? - How can SVE's D-values fit into current models of core formation? The partitioning experiments will be performed using a Walker type multi anvil apparatus in a pressure range between 10 and 20 GPa and temperatures of 1700 up to 2100 °C. To determine the Dmetal/silicate values we are using a field emission high-resolution JEOL JXA-8530F EPMA for major elements and a Photon Machines Analyte G2 Excimer laser (193 nm) ablation system coupled to a Thermo Fisher Element 2 single-collector ICP-MS (LA-ICP-MS) for the trace elements. We recently finished the first sets of experiments and can provide the

  15. Organic pollutants in the coastal environment off San Diego, California. 2: Petrogenic and biogenic sources of aliphatic hydrocarbons

    International Nuclear Information System (INIS)

    Tran, K.; Yu, C.C.; Zeng, E.Y.

    1997-01-01

    The results from the measurements of aliphatic hydrocarbons suggest that hydrocarbons suggest that hydrocarbons in the Point Loma Wastewater Treatment Plant (PLWTP) effluents are mainly petroleum derived; those in the Tijuana River runoff have largely originated from terrestrial plants with visible petroleum contamination; and those in the sea surface microlayer, sediment traps, and sediments at various coastal locations off San Diego have mostly resulted from biogenic contributions with enhanced microbial products in the summer season. Rainfall in the winter season appeared to amplify the inputs from terrestrial higher plants to the coastal areas. The PLWTP discharged approximately 3.85 metric tons of n-alkanes (C 10 -C 35 ) in 1994, well below the level (136 metric tons) estimated in 1979. The input of aliphatic hydrocarbons from the Tijuana River was about 0.101 metric tons in 1994. Diffusion, solubilization, evaporation, and microbial degradation seemed partially responsible for the difference in the concentrations and compositions of aliphatic hydrocarbons in different sample media, although the relative importance of each mechanism cannot be readily discerned from the available data. The results from analyses of aliphatic hydrocarbon compositional indices are generally consistent with those of polycyclic aromatic hydrocarbons

  16. Non-covalent Interactions of Graphene with Polycyclic Aromatic Hydrocarbons

    NARCIS (Netherlands)

    Zygouri, Panagiota; Potsi, Georgia; Mouzourakis, Eleftherios; Spyrou, Konstantinos; Gournis, Dimitrios; Rudolf, Petra

    2015-01-01

    In this mini review we discuss the interactions of polyaromatic hydrocarbons (PAHs) with graphene and the experimental approaches developed so far to create novel graphene/PAH hybrids and composite systems. The utilization of these systems in electrical, biomedical and polymer-reinforcement

  17. Magnetic nanoparticles-nylon 6 composite for the dispersive micro solid phase extraction of selected polycyclic aromatic hydrocarbons from water samples.

    Science.gov (United States)

    Reyes-Gallardo, Emilia M; Lucena, R; Cárdenas, S; Valcárcel, M

    2014-06-06

    In this article, the easy synthesis of magnetic nanoparticles-nylon 6 composite is presented, characterized and applied in the microextraction field. The one-step synthesis of the composite is performed by a solvent changeover playing with the different solubility of the polymeric network in formic acid and water. The new material has been characterized by different techniques including infrared spectroscopy, transmission and scanning microscopy. The extraction performance of the composite under a dispersive micro solid phase extraction format has been evaluated by determining four polycyclic aromatic hydrocarbons (benzo[b]fluoranthene, fluoranthene, indeno[1,2,3-cd]pyrene and phenanthrene) in water using ultra performance liquid chromatography (UPLC) combined with photo diode array detection. The developed methodology allows the determination of the analytes with limits of detection in the range from 0.05 μg/L (benzo[b]fluoranthene) to 0.58 μg/L (phenanthrene). The repeatability of the method was better than 6.9% at the limit of quantification level. The relative recoveries varied in the interval 80-111%. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Volatile phenols in wine: Control measures of Brettanomyces/Dekkera yeasts

    Directory of Open Access Journals (Sweden)

    Sanja Šućur

    2016-10-01

    Full Text Available This review focuses on the considerable amount of research regarding volatile phenols production by Brettanomyces and on microbiological and technological parameters that influence development of these compounds during all stages of grape processing and winemaking. Also, volatile phenols impact on wine aroma and quality and prevention methods were discussed. The yeast genus Brettanomyces is the major microorganism that has the ability to convert hydroxycinnamic acids into significant concentration of phenolic compounds, especially of 4-ethylphenol and 4-ethylguaiacol, in red wine. When volatile phenols reach concentrations above the sensory threshold in wine, it is then characterized as wine with fault. In order to control the growth of Brettanomyces and preclude volatile phenols production, it is helpful to keep good quality of grape, winery sanitation, control of oxygen and sulphite level, as well as orderly check physiochemical composition of wine.

  19. Effect of e-beam irradiation and microwave heating on the fatty acid composition and volatile compound profile of grass carp surimi

    International Nuclear Information System (INIS)

    Zhang, Hongfei; Wang, Wei; Wang, Haiyan; Ye, Qingfu

    2017-01-01

    In this study, we evaluated the effects of e-beam irradiationпј€1–7 kGyпј‰ and irradiation coupled to microwave heating (e-I-MC, 70 °C internal temperature) on the fatty acid composition and volatile compound profile of grass carp surimi. Compared to control samples, e-beam irradiation generated three novel volatile compounds (heptane, 2,6-dimethyl-nonane, and dimethyl disulfide) and increased the relative proportions of alcohols, aldehydes, and ketones. Meanwhile, e-I-MC significantly increased aldehyde levels and generated five heterocyclic compounds along with these three novel compounds. No significant difference in volatile compounds were detected in e-I-MC samples with increasing irradiation dose (p>0.05), comparing to the control group. E-beam irradiation at 5 and 7 kGy increased the levels of saturated fatty acids (SFAs) and decreased the levels of unsaturated fatty acids (p≤0.05), but did not affect the content of trans fatty acid levels (p>0.05). Irradiation, which had no significant effects on (Eicosapentaenoic acid) EPA, decreased (Docose Hexaenoie Acid) DHA levels. In the e-I-MC group, SFA levels increased and PUFA levels decreased. Additionally, MUFA levels were unaffected and trans fatty acid levels increased slightly following e-I-MC. - Highlights: • E-beam irradiation generated three novel volatile compounds. • E-beam irradiation increased the relative proportions of alcohols, aldehydes, and ketones. • E-beam irradiation coupled to microwave heating increased aldehyde levels and generated five heterocyclic compounds. • E-beam irradiation at 5 and 7 kGy decreased the levels of unsaturated fatty acids, but did not affect trans fatty acid levels.

  20. Quantitative estimates of the volatility of ambient organic aerosol

    Science.gov (United States)

    Cappa, C. D.; Jimenez, J. L.

    2010-06-01

    % to 400% of the OA mass, with smaller values generally corresponding to the higher ΔHvap assumptions. The volatility of various OA components determined from factor analysis of AMS spectra has also been assessed. In general, it is found that the fraction of non-volatile material follows the pattern: biomass burning OA hydrocarbon-like OA < semivolatile oxygenated OA < low-volatility oxygenated OA. Correspondingly, the sensitivity to dilution and the estimated amount of semivolatile gas-phase material for the OA factors follows the reverse order. Primary OA has a substantial semivolatile fraction, in agreement with previous results, while the non-volatile fraction appears to be dominated by oxygenated OA produced by atmospheric aging. The overall OA volatility is thus controlled by the relative contribution of each aerosol type to the total OA burden. Finally, the model/measurement comparison appears to require OA having an evaporation coefficient (γe) substantially greater than 10-2; at this point it is not possible to place firmer constraints on γe based on the observations.

  1. A temporal record of pre-eruptive magmatic volatile contents at Campi Flegrei: Insights from texturally-constrained apatite analyses

    Science.gov (United States)

    Stock, Michael J.; Isaia, Roberto; Humphreys, Madeleine C. S.; Smith, Victoria C.; Pyle, David M.

    2016-04-01

    Apatite is capable of incorporating all major magmatic volatile species (H2O, CO2, S, Cl and F) into its crystal structure. Analysis of apatite volatile contents can be related to parental magma compositions through the application of pressure and temperature-dependent exchange reactions (Piccoli and Candela, 1994). Once included within phenocrysts, apatite inclusions are isolated from the melt and preserve a temporal record of magmatic volatile contents in the build-up to eruption. In this work, we measured the volatile compositions of apatite inclusions, apatite microphenocrysts and pyroxene-hosted melt inclusions from the Astroni 1 eruption of Campi Flegrei, Italy (Stock et al. 2016). These data are coupled with magmatic differentiation models (Gualda et al., 2012), experimental volatile solubility data (Webster et al., 2014) and thermodynamic models of apatite compositional variations (Piccoli and Candela, 1994) to decipher pre-eruptive magmatic processes. We find that apatite halogen/OH ratios decreased through magmatic differentiation, while melt inclusion F and Cl concentrations increased. Melt inclusion H2O contents are constant at ~2.5 wt%. These data are best explained by volatile-undersaturated differentiation over most of the crystallisation history of the Astroni 1 melt, with melt inclusion H2O contents reset at shallow levels during ascent. Given the high diffusivity of volatiles in apatite (Brenan, 1993), the preservation of volatile-undersaturated melt compositions in microphenocrysts suggests that saturation was only achieved 10 - 103 days before eruption. We suggest that late-stage transition into a volatile-saturated state caused an increase in magma chamber overpressure, which ultimately triggered the Astroni 1 eruption. This has major implications for monitoring of Campi Flegrei and other similar volcanic systems. Piccoli and Candela, 1994. Am. J. of Sc., 294, 92-135. Stock et al., 2016, Nat. Geosci. Gualda et al., 2012. J. Pet., 53, 875

  2. Composition of LHB Comets and Their Influence on the Early Earth Atmosphere Composition

    Science.gov (United States)

    Tornow, C.; Kupper, S.; Ilgner, M.; Kuehrt, E.; Motschmann, U.

    2011-01-01

    Two main processes were responsible for the composition of this atmosphere: chemical evolution of the volatile fraction of the accretion material forming the planet and the delivery of gasses to the planetary surface by impactors during the late heavy bombardment (LHB). The amount and composition of the volatile fraction influences the outgassing of the Earth mantle during the last planetary formation period. A very weakened form of outgassing activity can still be observed today by examining the composition of volcanic gasses. An enlightenment of the second process is based on the sparse records of the LHB impactors resulting from the composition of meteorites, observed cometary comas, and the impact material found on the Moon. However, for an assessment of the influence of the outgassing on the one hand and the LHB event on the other, one has to supplement the observations with numerical simulations of the formation of volatiles and their incorporation into the accretion material which is the precursors of planetary matter, comets and asteroids. These simulations are performed with a combined hydrodynamic-chemical model of the solar nebula (SN). We calculate the chemical composition of the gas and dust phase of the SN. From these data, we draw conclusions on the upper limits of the water content and the amount of carbon and nitrogen rich volatiles incorporated later into the accretion material. Knowing these limits we determine the portion of major gas compounds delivered during the LHB and compare it with the related quantities of the outgassed species.

  3. Identification of irradiated chicken by GC/MS determination of radiation-induced volatile from the lipids

    International Nuclear Information System (INIS)

    Spiegelberg, A.; Helde, L.; Boegl, K.W.

    1991-01-01

    For the detection of irradiated meat, a procedure is reported which involves high vacuum distillation of the separated fat and analysis by gas chromatography/mass spectrometry (GC/MS) of hydrocarbons. This equipment was well sulted for the method described in this report for the detection of irradiated chicken by separating the volatiles from the lipid fraction and further identification by GC/MS. The results are based on investigations of 7 types of whole frozen chicken 2 types of frozen chicken thigh, and 1 type of frozen chicken. The results demonstrate that irradiated chicken can be monitored by cold-finger high-vacuum distillation-and further GC/MS-Identification of the major hydrocarbons formed during the radiolysis of lipids. The detection of these compounds was simplified by Single Ion Monitoring. 4 figs., 20 refs

  4. Reduced graphene oxide/δ-WO{sub 3} composites for volatile organic compounds sensing

    Energy Technology Data Exchange (ETDEWEB)

    Perfecto, Tarcisio Micheli; Zito, Cecilia de Almeida; Volanti, Diogo Paschoalini, E-mail: tarcisio93@hotmail.com [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Sao Paulo, SP (Brazil)

    2016-07-01

    Full text: Metal oxide semiconductors (MOS) is a simple and low-cost alternative to detect volatile organic compounds (VOCs) with fast response and recovery time [1]. In this context, reduced graphene oxide (RGO) is used in order to achieve a superior metal oxides gas sensing performance [2]. Thus, we report the synthesis of RGO/δ-WO{sub 3} composites by microwave-assisted hydrothermal method and its application in VOCs detection. The composites were prepared in a single-step using a graphene oxide dispersion, tungsten salt, ammonium oxalate hydrate as morphological control agent, and HCl in aqueous medium. The mixture was sealed in an autoclave and irradiated by microwave (800W) at 140 °C for 10 minutes. Then the sample was heating treatment at 400 °C for 1 hour. δ-WO{sub 3} single phase was also prepared by the same process without graphene oxide. The XRD results indicated the successful formation of triclinic phase of WO{sub 3} for both samples. FEG-SEM images showed the δ-WO{sub 3} nanoplates formation that are agglomerated and become more disperse and with irregular shape in RGO/δ-WO{sub 3} composite. TEM analysis revealed the interaction between RGO and δ-WO{sub 3} particles. The preliminary gas sensing results showed that increasing the operation temperature, more sensitive the composite RGO/δ-WO{sub 3} was toward the ethanol, methanol, acetone, toluene and benzene. So far, the highest response observed was to acetone at 300 °C. The response of RGO/δ-WO{sub 3} to 5, 10, 50, 100 and 200 ppm of acetone was 1.08, 1.12, 1.42, 1.75, and 1.99, respectively. We expect that increasing the operating temperature, more sensitive the material will become, since reports shows that WO{sub 3} sensors exhibit higher responses at higher temperatures [3]. Acknowledgments: The authors acknowledge FAPESP grants: 16/04371-1, 15/04306-2 and 14/17343-0. Refs.: [1] Jiang, D.;et al. RSC Adv. 2015, 5 (49), 39442-39448. [2] Jie, X.; et al. Sensors Actuators B Chem. 2015, 220

  5. Reduction of polycyclic aromatic hydrocarbons (PAHs) from petroleum-contaminated soil using thermal desorption technology

    International Nuclear Information System (INIS)

    Silkebakken, D.M.; Davis, H.A.; Ghosh, S.B.; Beardsley, G.P.

    1995-01-01

    The remediation of petroleum-contaminated soil typically requires the selection of a treatment option that addresses the removal of both volatile and semi-volatile organic compounds. Volatile organic compounds (VOCs), primarily BTEX (benzene, toluene, ethylbenzene, and xylenes) compounds, can be readily removed from the soil by a variety of well-established technologies. The semivolatile organic compounds, especially the polycyclic aromatic hydrocarbons (PAHS) that are characteristic of petroleum-contaminated soil, are not as amenable to conventional treatment. Low temperature thermal volatilization (LTTV) can be a viable treatment technology depending on the initial contaminant concentrations present and applicable cleanup objectives that must be attained. A-two-phase treatability study was conducted at 14 former underground storage tank (UST) sites to evaluate the applicability and effectiveness of LTTV for remediation of approximately 31,000 tons of PAH-contaminated soil. The PAHs of primary concern included benzo(a)anthracene, chrysene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(g,h,i)perylene, dibenz(a,h) anthracene, and indeno(1,2,3-cd)pyrene. During Phase 1, LTTV operational parameters were varied by trial-and-error and changes in soil treatment effectiveness were monitored. Phase B of the treatability study incorporated the appropriate treatment regime established during Phase 1 to efficiently remediate the remaining contaminated soil

  6. Pricing Volatility of Stock Returns with Volatile and Persistent Components

    DEFF Research Database (Denmark)

    Zhu, Jie

    In this paper a two-component volatility model based on the component's first moment is introduced to describe the dynamic of speculative return volatility. The two components capture the volatile and persistent part of volatility respectively. Then the model is applied to 10 Asia-Pacific stock m......, a positive or risk-premium effect exists between return and the volatile component, yet the persistent component is not significantly priced for return dynamic process....... markets. Their in-mean effects on return are also tested. The empirical results show that the persistent component accounts much more for volatility dynamic process than the volatile component. However the volatile component is found to be a significant pricing factor of asset returns for most markets...

  7. Herbivore-induced plant volatiles and tritrophic interactions across spatial scales.

    Science.gov (United States)

    Aartsma, Yavanna; Bianchi, Felix J J A; van der Werf, Wopke; Poelman, Erik H; Dicke, Marcel

    2017-12-01

    Herbivore-induced plant volatiles (HIPVs) are an important cue used in herbivore location by carnivorous arthropods such as parasitoids. The effects of plant volatiles on parasitoids have been well characterised at small spatial scales, but little research has been done on their effects at larger spatial scales. The spatial matrix of volatiles ('volatile mosaic') within which parasitoids locate their hosts is dynamic and heterogeneous. It is shaped by the spatial pattern of HIPV-emitting plants, the concentration, chemical composition and breakdown of the emitted HIPV blends, and by environmental factors such as wind, turbulence and vegetation that affect transport and mixing of odour plumes. The volatile mosaic may be exploited differentially by different parasitoid species, in relation to species traits such as sensory ability to perceive volatiles and the physical ability to move towards the source. Understanding how HIPVs influence parasitoids at larger spatial scales is crucial for our understanding of tritrophic interactions and sustainable pest management in agriculture. However, there is a large gap in our knowledge on how volatiles influence the process of host location by parasitoids at the landscape scale. Future studies should bridge the gap between the chemical and behavioural ecology of tritrophic interactions and landscape ecology. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  8. Dynamic measurement of coal thermal properties and elemental composition of volatile matter during coal pyrolysis

    Directory of Open Access Journals (Sweden)

    Rohan Stanger

    2014-01-01

    Full Text Available A new technique that allows dynamic measurement of thermal properties, expansion and the elemental chemistry of the volatile matter being evolved as coal is pyrolysed is described. The thermal and other properties are measured dynamically as a function of temperature of the coal without the need for equilibration at temperature. In particular, the technique allows for continuous elemental characterisation of tars as they are evolved during pyrolysis and afterwards as a function of boiling point. The technique is demonstrated by measuring the properties of maceral concentrates from a coal. The variation in heats of reaction, thermal conductivity and expansion as a function of maceral composition is described. Combined with the elemental analysis, the results aid in the interpretation of the chemical processes contributing to the physical and thermal behaviour of the coal during pyrolysis. Potential applications in cokemaking studies are discussed.

  9. Difference in the volatile composition of pine-mushrooms (Tricholoma matsutake Sing.) according to their grades.

    Science.gov (United States)

    Cho, In Hee; Choi, Hyung-Kyoon; Kim, Young-Suk

    2006-06-28

    The differences in volatile components of pine-mushrooms (Tricholoma matsutake Sing.) according to their grades were observed by applying multivariate statistical methods to GC-MS data sets. A total of 35 and 37 volatile components were identified in raw and cooked pine-mushrooms, respectively. The volatile components in pine-mushrooms were primarily composed of C8 species, such as 3-octanol, 1-octen-3-ol, 1-octanol, (E)-2-octen-1-ol, 3-octanone, 1-octen-3-one, (E)-2-octenal, and octanoic acid. The levels of ethyl octanoate, junipene, and 3-methyl-3-buten-2-one were much higher in raw pine-mushroom of higher grades, whereas the reverse was true for C8 components. On the other hand, furfuryl alcohol, benzyl alcohol, phenylethyl alcohol, dihydro-5-methyl-2(3H)-furanone, 2(5H)-furanone, (E)-2-methyl-2-butenal, furfural, phenylacetaldehyde, benzoic acid methyl ester, camphene, and beta-pinene were the major components of cooked mushrooms. These volatile components formed by various thermal reactions could be mainly responsible for the difference in volatile components of cooked pine-mushrooms according to their grades.

  10. Testing for Volatility Co-movement in Bivariate Stochastic Volatility Models

    OpenAIRE

    Chen, Jinghui; Kobayashi, Masahito; McAleer, Michael

    2017-01-01

    markdownabstractThe paper considers the problem of volatility co-movement, namely as to whether two financial returns have perfectly correlated common volatility process, in the framework of multivariate stochastic volatility models and proposes a test which checks the volatility co-movement. The proposed test is a stochastic volatility version of the co-movement test proposed by Engle and Susmel (1993), who investigated whether international equity markets have volatility co-movement using t...

  11. Performance audits and laboratory comparisons for SCOS97-NARSTO measurements of speciated volatile organic compounds

    Science.gov (United States)

    Fujita, Eric M.; Harshfield, Gregory; Sheetz, Laurence

    Performance audits and laboratory comparisons were conducted as part of the quality assurance program for the 1997 Southern California Ozone Study (SCOS97-NARSTO) to document potential measurement biases among laboratories measuring speciated nonmethane hydrocarbons (NMHC), carbonyl compounds, halogenated compounds, and biogenic hydrocarbons. The results show that measurements of volatile organic compounds (VOC) made during SCOS97-NARSTO are generally consistent with specified data quality objectives. The hydrocarbon comparison involved nine laboratories and consisted of two sets of collocated ambient samples. The coefficients of variation among laboratories for the sum of the 55 PAM target compounds and total NMHC ranged from ±5 to 15 percent for ambient samples from Los Angeles and Azusa. Abundant hydrocarbons are consistently identified by all laboratories, but discrepancies occur for olefins greater than C 4 and for hydrocarbons greater than C 8. Laboratory comparisons for halogenated compounds and biogenic hydrocarbons consisted of both concurrent ambient sampling by different laboratories and round-robin analysis of ambient samples. The coefficients of variation among participating laboratories were about 10-20 percent. Performance audits were conducted for measurement of carbonyl compounds involving sampling from a standard mixture of carbonyl compounds. The values reported by most of the laboratories were within 10-20 percent of those of the reference laboratory. Results of field measurement comparisons showed larger variations among the laboratories ranging from 20 to 40 percent for C 1-C 3 carbonyl compounds. The greater variations observed in the field measurement comparison may reflect potential sampling artifacts, which the performance audits did not address.

  12. Oil and stock market volatility: A multivariate stochastic volatility perspective

    International Nuclear Information System (INIS)

    Vo, Minh

    2011-01-01

    This paper models the volatility of stock and oil futures markets using the multivariate stochastic volatility structure in an attempt to extract information intertwined in both markets for risk prediction. It offers four major findings. First, the stock and oil futures prices are inter-related. Their correlation follows a time-varying dynamic process and tends to increase when the markets are more volatile. Second, conditioned on the past information, the volatility in each market is very persistent, i.e., it varies in a predictable manner. Third, there is inter-market dependence in volatility. Innovations that hit either market can affect the volatility in the other market. In other words, conditioned on the persistence and the past volatility in their respective markets, the past volatility of the stock (oil futures) market also has predictive power over the future volatility of the oil futures (stock) market. Finally, the model produces more accurate Value-at-Risk estimates than other benchmarks commonly used in the financial industry. - Research Highlights: → This paper models the volatility of stock and oil futures markets using the multivariate stochastic volatility model. → The correlation between the two markets follows a time-varying dynamic process which tends to increase when the markets are more volatile. → The volatility in each market is very persistent. → Innovations that hit either market can affect the volatility in the other market. → The model produces more accurate Value-at-Risk estimates than other benchmarks commonly used in the financial industry.

  13. Source rock hydrocarbons. Present status

    International Nuclear Information System (INIS)

    Vially, R.; Maisonnier, G.; Rouaud, T.

    2013-01-01

    This report first presents the characteristics of conventional oil and gas system, and the classification of liquid and gaseous non conventional hydrocarbons, with the peculiar case of coal-bed methane. The authors then describe how source rock hydrocarbons are produced: production of shale oils and gases (horizontal drilling, hydraulic fracturing, exploitation) and of coal-bed methane and coal mine methane. In the next part, they address and discuss the environmental impact of source rock hydrocarbon production: installation footprint, water resource management, drilling fluids, fracturing fluids composition, toxicity and recycling, air pollution, induced seismicity, pollutions from other exploitation and production activities. They propose an overview of the exploitation and production of source rock gas, coal-bed gas and other non conventional gases in the world. They describe the current development and discuss their economic impacts: world oil context and trends in the USA, in Canada and other countries, impacts on the North American market, on the world oil industry, on refining industries, on the world oil balance. They analyse the economic impacts of non conventional gases: development potential, stakes for the world gas trade, consequence for gas prices, development opportunities for oil companies and for the transport sector, impact on CO 2 emissions, macro-economic impact in the case of the USA

  14. Volatile compounds in samples of cork and also produced by selected fungi.

    Science.gov (United States)

    Barreto, M C; Vilas Boas, L; Carneiro, L C; San Romão, M V

    2011-06-22

    The production of volatile compounds by microbial communities of cork samples taken during the cork manufacturing process was investigated. The majority of volatiles were found in samples collected at two stages: resting after the first boiling and nontreated cork disks. Volatile profiles produced by microbiota in both stages are similar. The releasable volatile compounds and 2,4,6-trichloroanisole (TCA) produced in cork-based culture medium by five isolated fungal species in pure and mixed cultures were also analyzed by gas chromatography coupled with mass spectrometry (GC-MS).The results showed that 1-octen-3-ol and esters of fatty acids (medium chain length C8-C20) were the main volatile compounds produced by either pure fungal species or their mixture. Apparently, Penicillium glabrum is the main contributor to the overall volatile composition observed in the mixed culture. The production of releasable TCA on cork cannot be attributed to any of the assayed fungal isolates.

  15. Evolution of Volatile Compounds during the Distillation of Cognac Spirit.

    Science.gov (United States)

    Awad, Pierre; Athès, Violaine; Decloux, Martine Esteban; Ferrari, Gérald; Snakkers, Guillaume; Raguenaud, Patrick; Giampaoli, Pierre

    2017-09-06

    Cognac wine spirit has a complex composition in volatile compounds which contributes to its organoleptic profile. This work focused on the batch distillation process and, in particular, on volatile compounds specifically produced by chemical reactions during the distillation of Cognac wine spirit, traditionally conducted in two steps with charentais pot stills. The aim of this study was to characterize these volatile compounds formed during distillation. Sampling has been performed on the distillates and inside the boiler during a typical Cognac distillation. The analysis of these samples allowed us to perform a mass balance and to point out several types of volatile compounds whose quantities strongly increased during the distillation process. These compounds were distinguished by their chemical family. It has been found that the first distillation step was decisive for the formation of volatile compounds. Moreover, 2 esters, 3 aldehydes, 12 norisoprenoids, and 3 terpenes were shown to be generated during the process. These results suggest that some volatile compounds found in Cognac spirit are formed during distillation due to chemical reactions induced by high temperature. These findings give important indications to professional distillers in order to enhance the product's quality.

  16. Sensory profile and volatile aroma composition of reduced alcohol Merlot wines fermented with Metschnikowia pulcherrima and Saccharomyces uvarum.

    Science.gov (United States)

    Varela, C; Barker, A; Tran, T; Borneman, A; Curtin, C

    2017-07-03

    Strategies for production of wines containing lower alcohol concentrations are in strong demand, for reasons of quality, health, and taxation. Development and application of wine yeasts that are less efficient at transforming grape sugars into ethanol has the potential to allow winemakers the freedom to make lower alcohol wines from grapes harvested at optimal ripeness, without the need for post-fermentation processes aimed at removing ethanol. We have recently shown that two non-conventional wine yeast species Metschnikowia pulcherrima and Saccharomyces uvarum were both able to produce wine with reduced alcohol concentration. Both species produced laboratory-scale wines with markedly different volatile aroma compound composition relative to Saccharomyces cerevisiae. This work describes the volatile composition and sensory profiles of reduced-alcohol pilot-scale Merlot wines produced with M. pulcherrima and S. uvarum. Wines fermented with M. pulcherrima contained 1.0% v/v less ethanol than S. cerevisiae fermented wines, while those fermented with S. uvarum showed a 1.7% v/v reduction in ethanol. Compared to S. cerevisiae ferments, wines produced with M. pulcherrima showed higher concentrations of ethyl acetate, total esters, total higher alcohols and total sulfur compounds, while wines fermented with S. uvarum were characterised by the highest total concentration of higher alcohols. Sensorially, M. pulcherrima wines received relatively high scores for sensory descriptors such as red fruit and fruit flavour and overall exhibited a sensory profile similar to that of wine made with S. cerevisiae, whereas the main sensory descriptors associated with wines fermented with S. uvarum were barnyard and meat. This work demonstrates the successful application of M. pulcherrima AWRI3050 for the production of pilot-scale red wines with reduced alcohol concentration and highlights the need for rigorous evaluation of non-conventional yeasts with regard to their sensory impacts

  17. Diffusivity measurements of volatile organics in levitated viscous aerosol particles

    Science.gov (United States)

    Bastelberger, Sandra; Krieger, Ulrich K.; Luo, Beiping; Peter, Thomas

    2017-07-01

    Field measurements indicating that atmospheric secondary organic aerosol (SOA) particles can be present in a highly viscous, glassy state have spurred numerous studies addressing low diffusivities of water in glassy aerosols. The focus of these studies is on kinetic limitations of hygroscopic growth and the plasticizing effect of water. In contrast, much less is known about diffusion limitations of organic molecules and oxidants in viscous matrices. These may affect atmospheric chemistry and gas-particle partitioning of complex mixtures with constituents of different volatility. In this study, we quantify the diffusivity of a volatile organic in a viscous matrix. Evaporation of single particles generated from an aqueous solution of sucrose and small amounts of volatile tetraethylene glycol (PEG-4) is investigated in an electrodynamic balance at controlled relative humidity (RH) and temperature. The evaporative loss of PEG-4 as determined by Mie resonance spectroscopy is used in conjunction with a radially resolved diffusion model to retrieve translational diffusion coefficients of PEG-4. Comparison of the experimentally derived diffusivities with viscosity estimates for the ternary system reveals a breakdown of the Stokes-Einstein relationship, which has often been invoked to infer diffusivity from viscosity. The evaporation of PEG-4 shows pronounced RH and temperature dependencies and is severely depressed for RH ≲ 30 %, corresponding to diffusivities pollutant molecules such as polycyclic aromatic hydrocarbons (PAHs).

  18. Management of hydrocarbon-contaminated soil through bioremediation and landfill disposal at a remote location in northern Canada

    Energy Technology Data Exchange (ETDEWEB)

    Sanscartier, D.; Reimer, K.; Zeeb, B.; George, K. [Royal Military Coll. of Canada, Kingston, ON (Canada). Environmental Sciences Group; Royal Military Coll. of Canada, Kingston, ON (Canada). Dept. of Chemistry and Chemical Engineering

    2010-01-15

    This paper described an innovative method of managing diesel-contaminated soil in a remote Labrador community. The soil was treated in an aerated biopile to reduce mobile petroleum hydrocarbons (PHC) concentrations. The soil was then disposed of in a local landfill. An analysis of the soils showed that the method reduced total petroleum hydrocarbon (TPH) concentrations in the soil. Hydrocarbon concentrations were measured using the Canada-Wide standard reference method. TPH in leachate decreased during the 1-year field treatment period. PHC fractions were reduced to below the standard criteria for the protection of aquatic life. Volatilization was the predominant PHC removal mechanism in the field. The treated soils were used as a landfill cover for refuse. The cost of the treatment method compared favorably with other land remediation techniques. The biopile facility will be used to treat other fuel spills in the community and serve as a demonstration project for other communities. 36 refs., 4 tabs., 3 figs.

  19. Natural sparkling guava wine: volatile and physicochemical characterization

    Directory of Open Access Journals (Sweden)

    Silvana Maria Michelin Bertagnolli

    Full Text Available ABSTRACT: Although different tropical fruit species have been used in the development of fermented beverages, there are only few references in the literature to the production of natural sparkling wines from fruits other than grapes. In this sense, the objective of the present research was the development and physicochemical and volatile characterization of a natural sparkling guava wine produced by the champenoise method. Volatile compounds were identified by gas chromatography coupled to mass spectrometry using the headspace solid-phase microextraction (HS-SPME technique on samples. Eighty-nine volatile compounds were detected, of which 51 were identified. Esters were the predominant class of volatile compounds (a total of 26, followed by alcohols (10, terpenes (9, ketones (3, and acids (3. Volatile compounds with possible odoriferous activity were reported in the beverage, including ethyl octanoate, ethyl 5-hexenoate, phenethyl acetate, (E-β-damascenone, (E-ethyl cinnamate, 2-methyl butyl acetate, 3-methylbutanol, ethyl 3-(E-hexenoate, and methyl 5-hexenoate. Natural sparkling guava wine produced showed a complex composition of fruity and floral aromas. Furthermore, the use of the champenoise method, traditionally applied to grapes, enabled the manufacture of a natural sparkling guava wine with physicochemical characteristics equivalent to those of sparkling wines made from grapes.

  20. Comparison of two methods for extraction of volatiles from marine PL emulsions

    DEFF Research Database (Denmark)

    Lu, Henna Fung Sieng; Nielsen, Nina Skall; Jacobsen, Charlotte

    2013-01-01

    The dynamic headspace (DHS) thermal desorption principle using Tenax GR tube, as well as the solid phase micro‐extraction (SPME) tool with carboxen/polydimethylsiloxane 50/30 µm CAR/PDMS SPME fiber, both coupled to GC/MS were implemented for the isolation and identification of both lipid...... and Strecker derived volatiles in marine phospholipids (PL) emulsions. Comparison of volatile extraction efficiency was made between the methods. For marine PL emulsions with a highly complex composition of volatiles headspace, a fiber saturation problem was encountered when using CAR/PDMS‐SPME for volatiles...... analysis. However, the CAR/PDMS‐SPME technique was efficient for lipid oxidation analysis in emulsions of less complex headspace. The SPME method extracted volatiles of lower molecular weights more efficient than the DHS method. On the other hand, DHS Tenax GR appeared to be more efficient in extracting...

  1. Essential Oils’ Chemical Characterization and Investigation of Some Biological Activities: A Critical Review

    Science.gov (United States)

    Dhifi, Wissal; Bellili, Sana; Jazi, Sabrine; Bahloul, Nada; Mnif, Wissem

    2016-01-01

    This review covers literature data summarizing, on one hand, the chemistry of essential oils and, on the other hand, their most important activities. Essential oils, which are complex mixtures of volatile compounds particularly abundant in aromatic plants, are mainly composed of terpenes biogenerated by the mevalonate pathway. These volatile molecules include monoterpenes (hydrocarbon and oxygenated monoterpens), and also sesquiterpenes (hydrocarbon and oxygenated sesquiterpens). Furthermore, they contain phenolic compounds, which are derived via the shikimate pathway. Thanks to their chemical composition, essential oils possess numerous biological activities (antioxidant, anti-inflammatory, antimicrobial, etc…) of great interest in food and cosmetic industries, as well as in the human health field. PMID:28930135

  2. Pricing Volatility of Stock Returns with Volatile and Persistent Components

    DEFF Research Database (Denmark)

    Zhu, Jie

    2009-01-01

    This paper introduces a two-component volatility model based on first moments of both components to describe the dynamics of speculative return volatility. The two components capture the volatile and the persistent part of volatility, respectively. The model is applied to 10 Asia-Pacific stock ma...... markets. A positive or risk-premium effect exists between the return and the volatile component, yet the persistent component is not significantly priced for the return dynamic process....... markets. Their in-mean effects on returns are tested. The empirical results show that the persistent component is much more important for the volatility dynamic process than is the volatile component. However, the volatile component is found to be a significant pricing factor of asset returns for most...

  3. Laetiporus sulphureus, edible mushroom from Serbia: investigation on volatile compounds, in vitro antimicrobial activity and in situ control of Aspergillus flavus in tomato paste.

    Science.gov (United States)

    Petrović, Jovana; Glamočlija, Jasmina; Stojković, Dejan S; Ćirić, Ana; Nikolić, Miloš; Bukvički, Danka; Guerzoni, Maria Elisabetta; Soković, Marina D

    2013-09-01

    The volatile compounds of fruiting bodies of wild Laetiporus sulphureus (Bull.) Murrill, growing on willow trees from Serbia, were isolated and extracted using methanol, acetone and dichloromethane and investigated by GC/MS-SPME. A total of 56 components were identified in the extracts. Hydrocarbons predominated (76.90%, 77.20%, and 43.10%) in dichloromethane, acetone and methanol extracts, respectively. Fatty acids, esters and sesquiterpenes were present in amounts equal or lower than 2.00%. Ketones were represented with moderate amount with the exception of methanol extract where it reached as much as 28.90% of the total investigated compounds. Extracts were also tested for antimicrobial activity with and without the addition of food additive - potassium disulfite in vitro against eight bacterial and eight fungal species, and in situ in tomato paste against Aspergillus flavus. All the tested extracts showed good antimicrobial activity, but methanol extract with addition of E224 showed the best antimicrobial activity in vitro. In situ results indicate complete inhibition of A. flavus growth in tomato paste after 15 days of the treatment. This study is the first report on volatile composition of L. sulphureus growing wild in Serbia. We describe for the first time the application of its extract as antifungal food preservative. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Heterogeneous OH oxidation of motor oil particles causes selective depletion of branched and less cyclic hydrocarbons.

    Science.gov (United States)

    Isaacman, Gabriel; Chan, Arthur W H; Nah, Theodora; Worton, David R; Ruehl, Chris R; Wilson, Kevin R; Goldstein, Allen H

    2012-10-02

    Motor oil serves as a useful model system for atmospheric oxidation of hydrocarbon mixtures typical of anthropogenic atmospheric particulate matter, but its complexity often prevents comprehensive chemical speciation. In this work we fully characterize this formerly "unresolved complex mixture" at the molecular level using recently developed soft ionization gas chromatography techniques. Nucleated motor oil particles are oxidized in a flow tube reactor to investigate the relative reaction rates of observed hydrocarbon classes: alkanes, cycloalkanes, bicycloalkanes, tricycloalkanes, and steranes. Oxidation of hydrocarbons in a complex aerosol is found to be efficient, with approximately three-quarters (0.72 ± 0.06) of OH collisions yielding a reaction. Reaction rates of individual hydrocarbons are structurally dependent: compared to normal alkanes, reaction rates increased by 20-50% with branching, while rates decreased ∼20% per nonaromatic ring present. These differences in rates are expected to alter particle composition as a function of oxidation, with depletion of branched and enrichment of cyclic hydrocarbons. Due to this expected shift toward ring-opening reactions heterogeneous oxidation of the unreacted hydrocarbon mixture is less likely to proceed through fragmentation pathways in more oxidized particles. Based on the observed oxidation-induced changes in composition, isomer-resolved analysis has potential utility for determining the photochemical age of atmospheric particulate matter with respect to heterogeneous oxidation.

  5. High-density volatiles in the system C-O-H-N for the calibration of a laser Raman microprobe

    Science.gov (United States)

    Chou, I.-Ming; Pasteris, J.D.; Seitz, J.C.

    1990-01-01

    Three methods have been used to produce high-density volatiles in the system C-O-H-N for the calibration of a laser Raman microprobe (LRM): synthetic fluid-inclusion, sealed fused-quartz-tube, and high-pressure-cell methods. Because quantitative interpretation of a Raman spectrum of mixed-volatile fluid inclusions requires accurate knowledge of pressure- and composition-sensitive Raman scattering efficiencies or quantification factors for each species, calibrations of these parameters for mixtures of volatiles of known composition and pressure are necessary. Two advantages of the synthetic fluid-inclusion method are that the inclusions can be used readily in complementary microthermometry (MT) studies and that they have sizes and optical properties like those in natural samples. Some disadvantages are that producing H2O-free volatile mixtures is difficult, the composition may vary from one inclusion to another, the exact composition and density of the inclusions are difficult to obtain, and the experimental procedures are complicated. The primary advantage of the method using sealed fused-quartz tubes is its simplicity. Some disadvantages are that exact compositions for complex volatile mixtures are difficult to predict, densities can be approximated only, and complementary MT studies on the tubes are difficult to conduct. The advantages of the high-pressure-cell method are that specific, known compositions of volatile mixtures can be produced and that their pressures can be varied easily and are monitored during calibration. Some disadvantages are that complementary MT analysis is impossible, and the setup is bulky. Among the three methods for the calibration of an LRM, the high-pressure-cell method is the most reliable and convenient for control of composition and total pressure. We have used the high-pressure cell to obtain preliminary data on 1. (1) the ratio of the Raman quantification factors for CH4 and N2 in an equimolar CH4N2 mixture and 2. (2) the

  6. Volatility in energy prices

    International Nuclear Information System (INIS)

    Duffie, D.

    1999-01-01

    This chapter with 58 references reviews the modelling and empirical behaviour of volatility in energy prices. Constant volatility and stochastic volatility are discussed. Markovian models of stochastic volatility are described and the different classes of Markovian stochastic volatility model are examined including auto-regressive volatility, option implied and forecasted volatility, Garch volatility, Egarch volatility, multivariate Garch volatility, and stochastic volatility and dynamic hedging policies. Other volatility models and option hedging are considered. The performance of several stochastic volatility models as applied to heating oil, light oil, natural gas, electricity and light crude oil are compared

  7. Distinguishing natural hydrocarbons from anthropogenic contamination in ground water

    International Nuclear Information System (INIS)

    Lesage, S.; Xu, H.; Novakowski, K.S.

    1997-01-01

    Differentiation between natural and anthropogenic sources of ground-water contamination by petroleum hydrocarbons is necessary in areas where natural hydrocarbons may be present in the subsurface. Because of the similarity in composition between natural and refined petroleum, the use of statistical techniques to discern trends is required. In this study, both multivariate plotting techniques and principal component analysis were used to investigate the origin of hydrocarbons from a variety of study sites. Ground-water and gas samples were collected from the Niagara Falls area and from three gasoline stations where leaking underground storage tanks had been found. Although soil gas surveys are used to indicate the presence of hydrocarbons, they were not useful in differentiating between natural and anthropogenic sources of contamination in ground water. Propane and pentene were found to be the most useful chemical parameters in discriminating between the natural and anthropogenic sources. These chemicals are not usually measured in investigations of ground-water contamination, yet analysis can be conducted by most environmental laboratories using conventional methods

  8. Analysis of hydrocarbons generated in coalbeds

    Science.gov (United States)

    Butala, Steven John M.

    This dissertation describes kinetic calculations using literature data to predict formation rates and product yields of oil and gas at typical low-temperature conditions in coalbeds. These data indicate that gas formation rates from hydrocarbon thermolysis are too low to have generated commercial quantities of natural gas, assuming bulk first-order kinetics. Acid-mineral-catalyzed cracking, transition-metal-catalyzed hydrogenolysis of liquid hydrocarbons, and catalyzed CO2 hydrogenation form gas at high rates. The gaseous product compositions for these reactions are nearly the same as those for typical natural coalbed gases, while those from thermal and catalytic cracking are more representative of atypical coalbed gases. Three Argonne Premium Coals (Upper-Freeport, Pittsburgh #8 and Lewiston-Stockton) were extracted with benzene in both Soxhlet and elevated pressure extraction (EPE) systems. The extracts were compared on the basis of dry mass yield and hydrocarbon profiles obtained by gas chromatography/mass spectrometry. The dry mass yields for the Upper-Freeport coal gave consistent results by both methods, while the yields from the Pittsburgh #8 and Lewiston-Stockton coals were greater by the EPE method. EPE required ˜90 vol. % less solvent compared to Soxhlet extraction. Single-ion-chromatograms of the Soxhlet extracts all exhibited bimodal distributions, while those of the EPE extracts did not. Hydrocarbons analyzed from Greater Green River Basin samples indicate that the natural oils in the basin originated from the coal seams. Analysis of artificially produced oil indicates that hydrous pyrolysis mimics generation of C15+ n-alkanes, but significant variations were found in the branched alkane, low-molecular-weight n-alkanes, and high-molecular-weight aromatic hydrocarbon distributions.

  9. Hydrocarbon removal from bilgewater by a combination of air-stripping and photocatalysis

    Energy Technology Data Exchange (ETDEWEB)

    Cazoir, D., E-mail: david.cazoir@ircelyon.univ-lyon1.fr [University Lyon 1, Lyon, F-69626, France, CNRS, UMR5256, IRCELYON, Institut de Recherches sur la Catalyse et l' Environnement de Lyon, Villeurbanne, F-69626 (France); Fine, L.; Ferronato, C.; Chovelon, J.-M. [University Lyon 1, Lyon, F-69626, France, CNRS, UMR5256, IRCELYON, Institut de Recherches sur la Catalyse et l' Environnement de Lyon, Villeurbanne, F-69626 (France)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Bilge water is an oily effluent that contaminates oceans and seas (MARPOL73/78). Black-Right-Pointing-Pointer Hydrocarbon removal was studied by photocatalysis and air-stripping, together used. Black-Right-Pointing-Pointer Both aqueous and gaseous phases were monitored by GC-MS during the process. Black-Right-Pointing-Pointer The combined process showed a better efficiency and a synergistic effect. Black-Right-Pointing-Pointer N-Alkanes (N{sub C} > 15) appeared as being the most refractory compounds. - Abstract: In order to prevent hydrocarbon discharge at sea from the bilge of ships, the International Maritime Organization (IMO) enacted the MARPOL 73/78 convention in which effluents are now limited to those with maximum oil content of 15 ppmv. Thus, photocatalysis and air-stripping were combined for the hydrocarbon removal from a real oily bilgewater sample and an original monitoring of both aqueous and gaseous phases was performed by GC/MS to better understand the process. Our results show that the hydrocarbon oil index [HC] can be reduced to its maximum permissible value of 15 ppmv (MARPOL) in only 8.5 h when photocatalysis and air-stripping are used together in a synergistic way, as against 17 h when photocatalysis is used alone. However, this air-assisted photocatalytic process emits a large quantity of volatile organic compounds (VOC) and, within the first four hours, ca. 10% of the hydrocarbon removal in the aqueous phase is actually just transferred into the gaseous one. Finally, we highlight that the n-alkanes with a number of carbon atoms higher than 15 (N{sub C} > 15) are those which most decrease the rate of [HC] removal.

  10. Comparative study of volatile oil content and antimicrobial activity of pecan cultivars growing in Egypt.

    Science.gov (United States)

    El Hawary, Seham S; Zaghloul, Soumaya S; El Halawany, Ali M; El Bishbishy, Mahitab H

    2013-11-01

    The volatile oils obtained from the leaves of four pecan cultivars growing in Egypt were evaluated for their chemical composition and antimicrobial activity. The selected cultivars (cv.) were Carya illinoinensis (Wangneh.) K. Koch. cv. Wichita, C. illinoinensis cv. Western Schley, C. illinoinensis cv. Cherokee, and C. illinoinensis cv. Sioux. The gas chromatography-mass spectrometry analyses revealed that the volatile oils from samples of the different cultivars differ in composition and percentage of their components. β-Curcumene was found as the major constituent of the cv. Wichita oil, whereas germacrene D was the major component of cv. Sioux, cv. Cherokee, and cv. Western Schley. The antimicrobial activity was assayed using the Kirby-Bauer Method by measuring the zone of inhibition of growth. All volatile oils displayed an antimicrobial activity against the tested bacterial strains. On the other hand, only the volatile oil of cv. Wichita showed an antifungal effect on Aspergillus flavus. This work has identified candidates of volatile oils for future in vivo studies to develop antibiotic substitutes for the diminution of human and animal pathogenic bacteria. Nevertheless, the variations of the volatile oil components and antimicrobial potencies of the different studied cultivars, necessitate identifying the cultivars used in future studies.

  11. Volatile-mediated suppression of plant pathogens is related to soil properties and microbial community composition

    NARCIS (Netherlands)

    Van Agtmaal, M.; Straathof, A.L.; Termorshuizen, Aad J; Lievens, Bart; Hoffland, Ellis; De Boer, W.

    2018-01-01

    There is increasing evidence that the soil microbial community produces a suite of volatile organic compounds that suppress plant pathogens. However, it remains unknown which soil properties and management practices influence volatile-mediated pathogen suppression. The aim of this study was to

  12. Volatile-mediated suppression of plant pathogens is related to soil properties and microbial community composition

    NARCIS (Netherlands)

    Agtmaal, van Maaike; Straathof, Angela L.; Termorshuizen, Aad; Lievens, Bart; Hoffland, Ellis; Boer, de Wietse

    2018-01-01

    There is increasing evidence that the soil microbial community produces a suite of volatile organic compounds that suppress plant pathogens. However, it remains unknown which soil properties and management practices influence volatile-mediated pathogen suppression. The aim of this study was to

  13. The relationship between gasoline composition and vehicle hydrocarbon emissions: a review of current studies and future research needs.

    Science.gov (United States)

    Schuetzle, D; Siegl, W O; Jensen, T E; Dearth, M A; Kaiser, E W; Gorse, R; Kreucher, W; Kulik, E

    1994-10-01

    The purpose of this paper is to review current studies concerning the relationship of fuel composition to vehicle engine-out and tail-pipe emissions and to outline future research needed in this area. A number of recent combustion experiments and vehicle studies demonstrated that reformulated gasoline can reduce vehicle engine-out, tail-pipe, running-loss, and evaporative emissions. Some of these studies were extended to understand the fundamental relationships between fuel composition and emissions. To further establish these relationships, it was necessary to develop advanced analytical methods for the qualitative and quantitative analysis of hydrocarbons in fuels and vehicle emissions. The development of real-time techniques such as Fourier transform infrared spectroscopy, laser diode spectroscopy, and atmospheric pressure ionization mass spectrometry were useful in studying the transient behavior of exhaust emissions under various engine operating conditions. Laboratory studies using specific fuels and fuel blends were carried out using pulse flame combustors, single- and multicylinder engines, and vehicle fleets. Chemometric statistical methods were used to analyze the large volumes of emissions data generated from these studies. Models were developed that were able to accurately predict tail-pipe emissions from fuel chemical and physical compositional data. Some of the primary fuel precursors for benzene, 1,3-butadiene, formaldehyde, acetaldehyde and C2-C4 alkene emissions are described. These studies demonstrated that there is a strong relationship between gasoline composition and tail-pipe emissions.

  14. Determination of volatile polycyclic aromatic hydrocarbons in waters using headspace solid-phase microextraction with a benzyl-functionalized crosslinked polymeric ionic liquid coating.

    Science.gov (United States)

    Merdivan, Melek; Pino, Verónica; Anderson, Jared L

    2017-08-01

    A benzyl-functionalized crosslinked polymeric ionic liquid (PIL), produced through the co-polymerization of the 1-vinylbenzyl-3-hexadecylimidazolium bis[(trifluoromethyl)sulfonyl]imide (VBHDIM-NTf 2 ) ionic liquid (IL) monomer and 1,12-di(3-vinylbenzylimidazolium)dodecane bis[(trifluoromethyl)sulfonyl]imide ((DVBIM) 2 C 12- 2NTf 2 ) IL crosslinker, was successfully used as a sorbent coating in headspace solid-phase microextraction (SPME) coupled to gas chromatography (GC) with flame-ionization detection (FID) to determine seven volatile polycyclic aromatic hydrocarbons (PAHs) in environmental water samples. Optimum extraction conditions for the PAHs when using the novel sorbent include an extraction temperature of 50°C, an ionic strength content adjusted with 30% (w/v) NaCl in the aqueous sample, and an extraction time of 60 min. The extraction performance of the crosslinked PIL fiber was compared to the SPME commercial coating polydimethylsiloxane fiber. The calibration ranges of the studied PAHs were linear in the range of 0.02-20 µg L -1 for the crosslinked PIL fiber. The accuracy of the proposed method was demonstrated by examining the spiked recoveries of seven PAHs which produced values ranging from 67.2% to 130% (for river- and seawater samples), and precision values lower than 9.4% for a spiked level of 1 µg L -1 , and detection limits between 0.01 and 0.04 µg L -1 , which supports the sensitivity of the method using GC-FID.

  15. Determination of aromatic and PAH (polycyclic aromatic hydrocarbons) content of oily wastewaters

    Energy Technology Data Exchange (ETDEWEB)

    Lysyj, I.; Russell, E.C.

    1978-08-01

    An analytical scheme was developed for determining the total organic content and hydrocarbon concentration from a one-liter portion of a wastewater sample, and determining the volatile, suspended, and water-soluble fractions from a second, two-liter portion. Analyses of untreated and treated bilge wastewater from the U.S. Army Fort Eustis, Va., facility showed 10-300 ppm suspended organics and 10-300 ppm dissolved organics in the untreated bilge, and no suspended matter, but 700-2000 ppm dissolved organics, in the treated bilge wastewaters. Of the dissolved organics in untreated and treated wastewater, 70 and 10%, respectively, were extracted with chloroform; the organics in the treated water were probably biologically derived from petroleum degradation. Gas chromatographic/mass spectroscopic and high-pressure liquid chromatographic analyses of the chloroform extracts showed about equal parts of phenolic compounds and aromatic hydrocarbons, small amounts of heterocyclics, and traces of polycyclic aromatics in the untreated wastewater, and mainly phenolics in the treated water.

  16. Pinus nigra and Pinus pinaster needles as passive samplers of polycyclic aromatic hydrocarbons

    International Nuclear Information System (INIS)

    Piccardo, Maria Teresa; Pala, Mauro; Bonaccurso, Bruna; Stella, Anna; Redaelli, Anna; Paola, Gaudenzio; Valerio, Federico

    2005-01-01

    Nine polycyclic aromatic hydrocarbons (PAHs) were analysed in pine needles of different ages (from 6 to 30 months) collected from two species, Pinus nigra and Pinus pinaster, in seven sites located along a transect from a suburban to a rural area of Genoa (Italy). In all sites and for both species, concentrations of more volatile PAHs (phenanthrene, anthracene, fluoranthene, pyrene) were higher than those for other less volatile PAHs, which are preferentially sorbed to airborne particulates (benzo[a]anthracene, chrysene, benzofluoranthenes, benzo[a]pyrene). Concentrations of total PAHs found in P. nigra in the rural sites were, on the average, 2.3 times higher than those in P. pinaster growing nearby. In both pine species, concentrations of volatile PAHs increased according to needle age. Annual trends of other PAHs were more variable, with a general decrease in older needles. P. pinaster needles are shown to be more reliable passive samplers, since they are more resistant to plant diseases, and considerable variation in PAH concentration was observed in P. nigra needles with moulds and fungi. - The suitability of the pine needles as passive air samplers for persistent trace organics is demonstrated

  17. Pinus nigra and Pinus pinaster needles as passive samplers of polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Piccardo, Maria Teresa [Environmental Chemistry Laboratory, National Cancer Research Institute, Genova. L.go Rosanna Benzi n. 10, 16132 Genova (Italy)]. E-mail: chimamb@istge.it; Pala, Mauro [Environmental Chemistry Laboratory, National Cancer Research Institute, Genova. L.go Rosanna Benzi n. 10, 16132 Genova (Italy); Bonaccurso, Bruna [Environmental Chemistry Laboratory, National Cancer Research Institute, Genova. L.go Rosanna Benzi n. 10, 16132 Genova (Italy); Stella, Anna [Environmental Chemistry Laboratory, National Cancer Research Institute, Genova. L.go Rosanna Benzi n. 10, 16132 Genova (Italy); Redaelli, Anna [Environmental Chemistry Laboratory, National Cancer Research Institute, Genova. L.go Rosanna Benzi n. 10, 16132 Genova (Italy); Paola, Gaudenzio [Botany Department, Genoa University, C.so Dogali 1 canc., 16136 Genova (Italy); Valerio, Federico [Environmental Chemistry Laboratory, National Cancer Research Institute, Genova. L.go Rosanna Benzi n. 10, 16132 Genova (Italy)

    2005-01-01

    Nine polycyclic aromatic hydrocarbons (PAHs) were analysed in pine needles of different ages (from 6 to 30 months) collected from two species, Pinus nigra and Pinus pinaster, in seven sites located along a transect from a suburban to a rural area of Genoa (Italy). In all sites and for both species, concentrations of more volatile PAHs (phenanthrene, anthracene, fluoranthene, pyrene) were higher than those for other less volatile PAHs, which are preferentially sorbed to airborne particulates (benzo[a]anthracene, chrysene, benzofluoranthenes, benzo[a]pyrene). Concentrations of total PAHs found in P. nigra in the rural sites were, on the average, 2.3 times higher than those in P. pinaster growing nearby. In both pine species, concentrations of volatile PAHs increased according to needle age. Annual trends of other PAHs were more variable, with a general decrease in older needles. P. pinaster needles are shown to be more reliable passive samplers, since they are more resistant to plant diseases, and considerable variation in PAH concentration was observed in P. nigra needles with moulds and fungi. - The suitability of the pine needles as passive air samplers for persistent trace organics is demonstrated.

  18. Volatile compounds and sensory properties of Montasio cheese made from the milk of Simmental cows grazing on alpine pastures.

    Science.gov (United States)

    Bovolenta, S; Romanzin, A; Corazzin, M; Spanghero, M; Aprea, E; Gasperi, F; Piasentier, E

    2014-12-01

    The aim of this study was to analyze the volatile compounds, physicochemical characteristics, and sensory properties of Montasio, a semicooked pressed cheese, produced from the milk of the dual-purpose Italian Simmental cows grazing on alpine pastures. A total of 72 cows grazing on 2 pastures, which differed in botanical composition (nutrient-rich pasture vs. nutrient-poor pasture), received 2 different levels of supplementation (3.0 vs 1.5 kg/head per day). The experimental cheeses were produced from whole, raw milk and ripened for 60 d. Sixty-one volatile compounds, including alcohols (11), aldehydes (6), ketones (10), lactones (2), esters (6), hydrocarbons (3), carboxylic acids (6), phenolic compounds (4), monoterpenes (7), sesquiterpenes (1), sulfur compounds (4), and amines (1), were detected. The main families in terms of relative weight appeared to be carboxylic acids, esters, and alcohols. A panel of trained assessors described the experimental cheeses as having an intense color; small and evenly distributed eyes; an intense odor and flavor of milk-sour, milk, and cow; and a tender and creamy texture. The pasture type affected the volatile fraction, particularly ketones, phenolic compounds, and terpenes, which are overall higher in nutrient-poor pastures. A slight effect on the sensory analyses, in particular the effect of the cow attribute on odor and flavor, was perceived by the panelists. The cheeses produced on nutrient-rich pasture had higher b* (yellowness) index. These results were consistent with the color evaluation of the sensory panel. In addition, the pasture affected some textural attributes (adhesivity, creaminess, and granules) as perceived by the panelists. Concentrate supplementation, which is required to meet the feeding requirements of grazing cows, had no clear effect on either the volatile compounds or the sensory properties of the cheeses. Thus, at least within levels of integration adopted, it is expected not to alter the organoleptic

  19. Enhancement of aromatic and saturated hydrocarbon by modified ...

    African Journals Online (AJOL)

    Three sediment samples collected from the Qua Iboe River System and eighteen different column packing ratios of silica gel and alumina were used in this investigation. The variation of the composition of the stationary phase (silica gel and alumina, SA) gave different yields of aromatic and saturated hydrocarbons. In all the ...

  20. Characterization of elemental and polycyclic aromatic hydrocarbon compositions of urban air in Brisbane

    Science.gov (United States)

    Lim, McKenzie C. H.; Ayoko, Godwin A.; Morawska, Lidia

    Characterization of the elemental and polycyclic aromatic hydrocarbons (PAHs) compositions of urban air was undertaken at three major sites in Brisbane, Australia. 17 elements and 16 US EPA priority PAHs were quantified at the sites. The most commonly detected elements in the TSP and PM 2.5 fractions were Al, Cd, Co, Cr, Cu, Fe, Mn, Mo, Si, Sn, Sr and Zn. Compared to the two other sites, PM 2.5 was found to contain higher concentrations of Zr, Mo, V, Al, Mn and Sr at the Queensland University of Technology (QUT) site. In contrast, the Woolloongabba sampling site, which was highly influenced by the vehicular emission and local industrial activities, has higher concentrations of Co, Sn, Cu, Zn and Mg while ANZ site has significantly lower concentration levels of most elements than the other sites; possibly due to the shielding effect of the nearby bush and forest. NAP, PHE, ANT, FLT, PYR and CRY were the most widespread PAHs found in all sites. But only QUT and Woolloongabba bus platform sites had detectable levels of the most carcinogenic US EPA PAH, BAP. The multi-criteria decision making procedures, Preference Ranking Organisation Method for Enrichment Evaluation (PROMETHEE) and Geometrical Analysis for Interactive Aid (GAIA) were used to rank the air samples and to identify the sources of the pollutants. Thus Woolloongabba bus platform was ranked as the most polluted site on the basis of the elemental and PAH compositions of its air samples while Woolloongabba bus platform and QUT sites were ranked as the worst polluted sites in terms of PAHs and PM 2.5 elemental contents, respectively.

  1. Volatility Discovery

    DEFF Research Database (Denmark)

    Dias, Gustavo Fruet; Scherrer, Cristina; Papailias, Fotis

    The price discovery literature investigates how homogenous securities traded on different markets incorporate information into prices. We take this literature one step further and investigate how these markets contribute to stochastic volatility (volatility discovery). We formally show...... that the realized measures from homogenous securities share a fractional stochastic trend, which is a combination of the price and volatility discovery measures. Furthermore, we show that volatility discovery is associated with the way that market participants process information arrival (market sensitivity......). Finally, we compute volatility discovery for 30 actively traded stocks in the U.S. and report that Nyse and Arca dominate Nasdaq....

  2. Farmed and wild sea bass (Dicentrarchus labrax) volatile metabolites: a comparative study by SPME-GC/MS.

    Science.gov (United States)

    Vidal, Natalia P; Manzanos, María J; Goicoechea, Encarnación; Guillén, María D

    2016-03-15

    Farmed and wild European sea bass (Dicentrarchus labrax) could be distinguished by its volatile metabolites, an issue not addressed until now. The aim of this work was to study these metabolites by solid-phase microextraction followed by gas chromatography/mass spectrometry (SPME-GC/MS). Both farmed and wild sea bass have a great number of volatile metabolites, most of them being in low concentrations. These include alcohols, aldehydes, ketones, alkylfurans, acids, aliphatic and aromatic hydrocarbons, terpenes, sulfur and nitrogen derivatives, 2,6-di-tert-butyl-4-methylphenol and one derived compound, as well as 2,4,7,9-tetramethyl-5-decyne-4,7-diol, this latter compound presumably resulting from environmental contamination. Important differences have been detected between both types of sea bass, and also among individuals inside each group. Farmed specimens are richer in volatile metabolites than the wild counterparts; however, these latter, in general, contain a high number and abundance of metabolites resulting from microbial and enzymatic non-oxidative activity than the former. Clear differences in the volatile metabolites of wild and farmed sea bass have been found. A great deal of valuable information on sea bass volatile metabolites has been obtained, which can be useful in understanding certain aspects of the quality and safety of raw and processed sea bass. © 2015 Society of Chemical Industry.

  3. Chemical composition and non-volatile components of three wild edible mushrooms collected from northwest Tunisia

    Directory of Open Access Journals (Sweden)

    ibtissem Kacem Jedidi

    2016-04-01

    Full Text Available In Tunisia, many people collect wild edible mushrooms as pickers for their own consumption. The present work aims at contributing to the determination of the chemical composition, non volatile components content (soluble sugars, free amino acids and minerals and trace elements of three popular Tunisian wild edible mushrooms species collected from the northwest of Tunisia (Agaricus campestris, Boletus edulis and Cantharellus cibarius.All investigated mushrooms revealed that these species are rich sources of proteins (123.70 – 374.10 g kg-1 dry weight (DW and carbohydrates (403.3 – 722.40 g kg-1 DW, and low content of fat (28.2 – 39.9 g kg-1 DW; the highest energetic contribution was guaranteed by C. cibarius (1542.71 kJ / 100 g. A. compestris (33.14 mg/g DW showed the highest concentration of essential amino acids. The composition in individual sugars was also determined, mannitol and trehalose being the most abundant sugars. C. cibarius revealed the highest concentrations of carbohydrates (722.4 g kg-1 DW and A. compestris the lowest concentration (403.3 g kg-1 DW. Potassium (K and sodium (Na are the most abundant minerals in analyzed samples (A. compestris showed the highest concentrations of K and Na, 49141.44 and 9263.886 µg/g DW respectively.

  4. The Amoco CadizOil Spill: Evolution of Petroleum Hydrocarbons in the Ile Grande Salt Marshes (Brittany) after a 13-year Period

    Science.gov (United States)

    Mille, G.; Munoz, D.; Jacquot, F.; Rivet, L.; Bertrand, J.-C.

    1998-11-01

    The Ile Grande salt marshes (Brittany coast) were polluted by petroleum hydrocarbons after theAmoco Cadizgrounding in 1978. Thirteen years after the oil spill, sediments were analysed for residual hydrocarbons in order to monitor the aliphatic and aromatic hydrocarbon signatures and to assess both qualitatively and quantitatively the changes in composition of theAmoco Cadizoil. Six stations were selected in the Ile Grande salt marshes and sediments were sampled to a depth of 20 cm. For each sample, the hydrocarbon compositions were determined for alkanes, alkenes, aromatics and biomarkers (terpanes, steranes, diasteranes). Hydrocarbon levels drastically decreased between 1978 and 1991, but to different extents according to the initial degree of contamination. In 1991, hydrocarbon concentrations never exceeded 1·7 g kg-1sediment dry weight, and in most cases were less than 0·1 g kg-1sediment dry weight. Even though petroleum hydrocarbons are still present, natural hydrocarbons were also detected at several stations. Changes in some biomarker distributions were observed 13 years after the oil spill. Nevertheless, most of the biomarkers are very stable in the salt marsh environment and remain unaltered even after a 13-year period.

  5. Biodegradation testing of hydrophobic chemicals in mixtures at low concentrations – covering the chemical space of petroleum hydrocarbons

    DEFF Research Database (Denmark)

    Birch, Heidi; Hammershøj, Rikke Høst; Mayer, Philipp

    Petroleum products are complex mixtures of varying composition containing thousands of hydrocarbons each with their own physicochemical properties and degradation kinetics. One approach for risk assessment of these products is therefore to group the hydrocarbons by carbon number and chemical class...... i.e. hydrocarbon blocks. However, the biodegradation kinetic data varies in quantity and quality for the different hydrocarbon blocks, hampering the characterization of their fate properties. In this study, biodegradation kinetics of a large number of hydrocarbons aiming to cover the chemical space...... of petroleum hydrocarbons, were therefore determined at ng/L to µg/L concentrations in surface water, seawater and activated sludge filtrate. Two hydrocarbon mixtures were prepared, comprising a total of 53 chemicals including paraffins, naphthenics and aromatic hydrocarbons from C8 to C20. Passive dosing from...

  6. Level Shifts in Volatility and the Implied-Realized Volatility Relation

    DEFF Research Database (Denmark)

    Christensen, Bent Jesper; de Magistris, Paolo Santucci

    We propose a simple model in which realized stock market return volatility and implied volatility backed out of option prices are subject to common level shifts corresponding to movements between bull and bear markets. The model is estimated using the Kalman filter in a generalization to the mult......We propose a simple model in which realized stock market return volatility and implied volatility backed out of option prices are subject to common level shifts corresponding to movements between bull and bear markets. The model is estimated using the Kalman filter in a generalization...... to the multivariate case of the univariate level shift technique by Lu and Perron (2008). An application to the S&P500 index and a simulation experiment show that the recently documented empirical properties of strong persistence in volatility and forecastability of future realized volatility from current implied...... volatility, which have been interpreted as long memory (or fractional integration) in volatility and fractional cointegration between implied and realized volatility, are accounted for by occasional common level shifts....

  7. Testing for Volatility Co-movement in Bivariate Stochastic Volatility Models

    NARCIS (Netherlands)

    J. Chen (Jinghui); M. Kobayashi (Masahito); M.J. McAleer (Michael)

    2017-01-01

    markdownabstractThe paper considers the problem of volatility co-movement, namely as to whether two financial returns have perfectly correlated common volatility process, in the framework of multivariate stochastic volatility models and proposes a test which checks the volatility co-movement. The

  8. Characterization of volatile constituents in commercial oak wood chips.

    Science.gov (United States)

    Fernández de Simón, Brígida; Muiño, Iria; Cadahía, Estrella

    2010-09-08

    The volatile composition of the different oak wood pieces (chips of Quercus spp.) that can be found on the market to be used as alternatives to barrels for aging wines, as well as of chips of Quercus pyrenaica which are being introduced, was studied, evaluating the contents of volatile phenols, lactones, furanic compounds, pyranones, phenolic aldehydes, phenolic ketones, and others. In regard to the overall results, the volatile composition of these products varies widely and has not been clearly laid out according to either the oak species or the wood toasting intensity. Taking into account that the different characteristics of alternatives to barrel products are reflected in the wine treated with them and that an oenological profile based on these variables (origin and toasting level) cannot be defined, only an appropriate chemical analysis would reveal the quality of alternative-to-barrel products and allow us to attempt to foresee its effects on the chemical and organoleptic characteristics of the wines treated with them. On the other hand, the Q. pyrenaica alternative products are very similar to those of other species, with some aromatic particularities, such as their high levels of furanic compounds, eugenol, Furaneol, and cis-whiskylactone, and low levels of vanillin.

  9. Volatile organic compound emissions from the oil and natural gas industry in the Uinta Basin, Utah: point sources compared to ambient air composition

    OpenAIRE

    C. Warneke; F. Geiger; P. M. Edwards; W. Dube; G. Pétron; J. Kofler; A. Zahn; S. S. Brown; M. Graus; J. Gilman; B. Lerner; J. Peischl; T. B. Ryerson; J. A. de Gouw; J. M. Roberts

    2014-01-01

    The emissions of volatile organic compounds (VOCs) associated with oil and natural gas production in the Uinta Basin, Utah were measured at a ground site in Horse Pool and from a NOAA mobile laboratory with PTR-MS instruments. The VOC compositions in the vicinity of individual gas and oil wells and other point sources such as evaporation ponds, compressor stations and injection wells are compared to the measurements at Horse Pool. High mixing ratios of aroma...

  10. Lewis-Acid/Base Effects on Gallium Volatility in Molten Chlorides

    International Nuclear Information System (INIS)

    Williams, D.F.

    2001-01-01

    It has been proposed that GaCl 3 can be removed by direct volatilization from a Pu-Ga alloy that is dissolved in a molten chloride salt. Although pure GaCl 3 is quite volatile (boiling point, 201 C), the behavior of GaCl 3 dissolved in chloride salts is different due to solution effects and is critically dependent on the composition of the solvent salt (i.e., its Lewis-acid/base character). In this report, the behavior of gallium in prototypical Lewis-acid and Lewis-base salts is compared. It was found that gallium volatility is suppressed in basic melts and enhanced in acidic melts. The implications of these results on the potential for simple gallium removal in molten salt systems are significant

  11. An approximate method for calculating composition of the non-equilibrium explosion products of hydrocarbons and oxygen

    International Nuclear Information System (INIS)

    Shargatov, V A; Gubin, S A; Okunev, D Yu

    2016-01-01

    We develop a method for calculating the changes in composition of the explosion products in the case where the complete chemical equilibrium is absent but the bimolecular reactions are in quasi-equilibrium with the exception bimolecular reactions with one of the components of the mixture. We investigate the possibility of using the method of 'quasiequilibrium' for mixtures of hydrocarbons and oxygen. The method is based on the assumption of the existence of the partial chemical equilibrium in the explosion products. Without significant loss of accuracy to the solution of stiff differential equations detailed kinetic mechanism can be replaced by one or two differential equation and a system of algebraic equations. This method is always consistent with the detailed mechanism and can be used separately or in conjunction with the solution of a stiff system for chemically non-equilibrium mixtures replacing it when bimolecular reactions are near to equilibrium. (paper)

  12. Volatiles and primary metabolites profiling in two Hibiscus sabdariffa (roselle) cultivars via headspace SPME-GC-MS and chemometrics.

    Science.gov (United States)

    Farag, Mohamed A; Rasheed, Dalia M; Kamal, Islam M

    2015-12-01

    Hibiscus sabdariffa (roselle) is a plant of considerable commercial importance worldwide as functional food due to its organic acids, mucilage, anthocyanins, macro and micro-nutrients content. Although Hibiscus flowers are emerging as very competitive targets for phytochemical studies, very little is known about their volatile composition and or aroma, such knowledge can be suspected to be relevant for understanding its olfactory and taste properties. To provide insight into Hibiscus flower aroma composition and for its future use in food and or pharmaceutical industry, volatile constituents from 2 cultivars grown in Egypt, viz. Aswan and Sudan-1 were profiled using solid-phase microextraction (SPME) coupled to GCMS. A total of 104 volatiles were identified with sugar and fatty acid derived volatiles amounting for the major volatile classes. To reveal for cultivar effect on volatile composition in an untargeted manner, multivariate data analysis was applied. Orthogonal projection to latent structures-discriminant analysis (OPLS-DA) revealed for 1-octen-3-ol versus furfural/acetic acid enrichment in Aswan and Sudan-1 cvs., respectively. Primary metabolites contributing to roselle taste and nutritional value viz. sugars and organic acids were profiled using GC-MS after silylation. The impact of probiotic bacteria on roselle infusion aroma profile was further assessed and revealed for the increase in furfural production with Lactobacillus plantarum inoculation and without affecting its anthocyanin content. This study provides the most complete map for volatiles, sugars and organic acids distribution in two Hibiscus flower cultivars and its fermented product. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Ecological risk assessment of a site contaminated with petroleum hydrocarbons

    International Nuclear Information System (INIS)

    Starodub, M.E.; Feniak, N.A.; Willes, R.F.; Moore, C.E.; Mucklow, L.

    1995-01-01

    The aquatic and terrestrial health risks associated with petroleum contamination on a decommissioned military base, contaminated with products ranging from Bunker C oil to aviation fuel, were assessed using a methodology whereby an analytical measurement of total petroleum hydrocarbons (TPH) could be correlated with compositional characterization and thus with toxicity. The constituents of petroleum hydrocarbon contamination represent wide ranges of physical-chemical properties, environmental fate, and toxicity. The composition of TPH can vary greatly, dependent on the sources or fuel types and the interaction of age as well as site- and chemical-specific characteristics in determining the impact of weathering processes. Therefore, a bulk sum analysis of TPH cannot be related to toxicity without characterization of its composition and association of the constituents, and therefore composition, with actual toxicity data. To address this need, the constituents of TPH were represented by surrogate chemicals, with selection based on structure-activity relationships and available toxicity data. Toxicological profiles were developed from governmental regulations and on the published literature for both the aquatic and terrestrial media. Risk characterization consisted of a comparison of water concentration limits and exposure limits, developed for each surrogate, to estimated surrogate concentrations throughout the site. The concentrations of surrogates were extrapolated from TPH composition characterization analyses, conducted at a select number of sampling locations, to bulk sum analyses of TPH at related sampling locations

  14. Perchlorate and Volatiles in the Brine of Lake Vida (antarctica): Implication for the Analysis of Mars Sediments

    Science.gov (United States)

    Kenig, F. P. H.; Chou, L.; McKay, C.; Jackson, W. A.; Doran, P. T.; Murray, A. E.; Fritsen, C. H.

    2015-12-01

    A cold (-13.4 °C), saline (188 psu) evaporative brine is encapsulated in the thick (> 27 m) ice of Lake Vida (McMurdo Dry Valleys, Antarctica). The Lake Vida brine (LVBr), which contains abundant dissolved organic carbon (48.2 mmol/L), support an active but slow microbial community. LVBr contains oxychlorines with 50 μg/L of perchlorate and 11 μg/L of chlorate. The McMurdo Dry Valleys have often been considered as a good Mars analog. The oxychlorine-rich brine of Lake Vida constitutes a potential equivalent to perchlorate-rich preserved saline liquid water on Mars. We report here on the artifacts created by oxychlorines upon analysis of volatiles and volatile organic compounds (VOCs) of LVBr by direct immersion (DI) and head space (HS) solid phase micro extraction (SPME) gas chromatography-mass spectrometry (GCMS). We compare analytical blanks to a standard containing 40 μg/L of perchlorate and to actual LVBr sample runs. All blanks, perchlorate blanks and samples were analyzed using two types of SPME fibers, CarboxenTM/polydimethylsiloxane (PDMS) and divinylbenzene (DVB)/ PDMS. The similarities and differences between our results and those obtained by the Sample Analysis at Mars instruments of the rover Curiosity are discussed. The volatiles evolved from LVBr upon analysis with DI- and HS-SPME GCMS are dominated by CO2, dichloromethane, HCl, and volatile organic sulfur compounds (VOSCs, such as DMS, DMDS). The volatiles also include oxygenated compounds such as acids and ketones, aromatic compounds, hydrocarbons, chlorinated compounds (dominated by dichloromethane). Apart from the VOSCs, short chain hydrocarbons and some functionalized compounds derived from the brine itself, all compounds observed are artifacts formed upon oxychlorine breakdown in the injector of the GCMS. The distribution of aromatic compounds seems to be directly dependant on the type of SPME fiber used. The perchlorate blanks show a clear pattern of carbon limitation, likely affecting the

  15. Stability of hydrocarbon systems at thermobaric conditions corresponding to depth down to 50 km

    Science.gov (United States)

    Kutcherov, V.; Kolesnikov, A.; Mukhina, E.; Serovaiskii, A.

    2017-12-01

    Most of the theoretical models show that crude oil stability is limited by the depth of 6-8 km (`oil window'). Commercial discovery of crude oil deposits on the depth more than 10 km in the different petroleum basins worldwide casts doubt on the validity of the above-mentioned theoretical calculations. Therefore, the question at which depth complex hydrocarbon systems could be stable is important not only from fundamental research point of view but has a great practical application. To answer this question a hydrocarbon mixture was investigated under thermobaric conditions corresponding to the conditions of the Earth's lower crust. Experiments were conducted by means of Raman Mössbauer spectroscopy. The results obtained show that the complex hydrocarbon systems could be stable and remain their qualitative and quantitative composition at temperature 320-450 °C and pressure 0.7-1.4 GPa. The oxidizing resistance of hydrocarbon system was tested in the modelled the Earth's crust surrounding. The hydrocarbon system stability at the presence of Fe2O3 strongly confirms that the Earth's crust oxygen fugacity does not influence on petroleum composition. The data obtained broaden our knowledge about the possible range of depths for crude oil and natural gas deposits in the Earth's crust and give us the possibility to revise the depth of petroleum deposits occurrence.

  16. Adsorption of Volatile Organic Compounds from Aqueous Solution by Granular Activated Carbon in Batch System

    International Nuclear Information System (INIS)

    Zeinali, F.; Ghoreyshi, A. A.; Najafpour, G.

    2011-01-01

    Chlorinated hydrocarbons and aromatics are the major volatile organic compounds that contaminate the ground water and industrial waste waters. The best way to overcome this problem is to recover the dissolved compounds in water. In order to evaluate the potential ability of granular activated carbon for recovery of volatile organic compounds from water, the equilibrium adsorption was investigated. This study deals with the adsorption of dichloromethane as a typical chlorinated volatile organic compound and toluene as the representative of aromatic volatile organic compounds on a commercial granular activated carbon. The adsorption isotherms of these two volatile organic compounds on granular activated carbon were measured at three different temperatures, toluene at 293, 303 and 313 K and dichloromethane at 298, 303 and 313 K within their solubility concentration range in water. The maximum adsorption capacity of dichloromethane and toluene adsorption by granular activated carbon was 4 and 0.2 mol/Kg-1, respectively. The experimental data obtained were correlated with different adsorption isotherm models. The Langmuir model was well adapted to the description of dichloromethane adsorption on granular activated carbon at all three temperatures, while the adsorption of toluene on granular activated carbon was found to be well described by the Langmuir-BET hybrid model at all three temperatures. The heat of adsorption was also calculated based on the thermodynamic equation of Clausius Clapeyron, which indicates the adsorption process is endothermic for both compounds.

  17. Chemical composition of the volatile extract and antioxidant activities of the volatile and nonvolatile extracts of Egyptian corn silk (Zea mays L.).

    Science.gov (United States)

    El-Ghorab, Ahmed; El-Massry, Khaled F; Shibamoto, Takayuki

    2007-10-31

    A total of 36 compounds, which comprised 99.4% of the extract, were identified by gas chromatography and mass spectrometry (GC-MS) in the volatile dichloromethane extract obtained from Egyptian corn silk. The main constituents of the volatile extract were cis-alpha-terpineol (24.22%), 6,11-oxidoacor-4-ene (18.06%), citronellol (16.18%), trans-pinocamphone (5.86%), eugenol (4.37%), neo-iso-3-thujanol (2.59%), and cis-sabinene hydrate (2.28%). Dried Egyptian corn silk was also directly extracted with petroleum ether, ethanol, and water. All extracts from solvent extraction and the volatile extract described above exhibited clear antioxidant activities at levels of 50-400 microg/mL in the 2,2-diphenyl-1-picrylhydrazyl (DPPH)/linoleic acid assay. The ethanol extract inhibited DPPH activity by 84% at a level of 400 microg/mL. All samples tested via the beta-carotene bleaching assay also exhibited satisfactory antioxidant activity with clear dose responses. This study indicates that corn silk could be used to produce novel natural antioxidants as well as a flavoring agent in various food products.

  18. Fundamental mass transfer modeling of emission of volatile organic compounds from building materials

    Science.gov (United States)

    Bodalal, Awad Saad

    In this study, a mass transfer theory based model is presented for characterizing the VOC emissions from building materials. A 3-D diffusion model is developed to describe the emissions of volatile organic compounds (VOCs) from individual sources. Then the formulation is extended to include the emissions from composite sources (system comprising an assemblage of individual sources). The key parameters for the model (The diffusion coefficient of the VOC in the source material D, and the equilibrium partition coefficient k e) were determined independently (model parameters are determined without the use of chamber emission data). This procedure eliminated to a large extent the need for emission testing using environmental chambers, which is costly, time consuming, and may be subject to confounding sink effects. An experimental method is developed and implemented to measure directly the internal diffusion (D) and partition coefficients ( ke). The use of the method is illustrated for three types of VOC's: (i) Aliphatic Hydrocarbons, (ii) Aromatic Hydrocarbons and ( iii) Aldehydes, through typical dry building materials (carpet, plywood, particleboard, vinyl floor tile, gypsum board, sub-floor tile and OSB). Then correlations for predicting D and ke based solely on commonly available properties such as molecular weight and vapour pressure were proposed for each product and type of VOC. These correlations can be used to estimate the D and ke when direct measurement data are not available, and thus facilitate the prediction of VOC emissions from the building materials using mass transfer theory. The VOC emissions from a sub-floor material (made of the recycled automobile tires), and a particleboard are measured and predicted. Finally, a mathematical model to predict the diffusion coefficient through complex sources (floor adhesive) as a function of time was developed. Then this model (for diffusion coefficient in complex sources) was used to predict the emission rate from

  19. PERUBAHAN KOMPOSISI VOLATIL DAGING BUAH MANGGA "KENSINGTON PRIDE" SELAMA PEMASAKAN [Changes in Volatile Compound Composition of Kensington Pride Mango Pulp During Fruit Ripening

    Directory of Open Access Journals (Sweden)

    Herianus J.D Lalel

    2003-08-01

    Full Text Available Volatile compounds of ‘Kesington Pride’ mango produced from the pulp during fruit ripening were studied using headspace solid-phase microextraction (SPME as a sampling method and gas chromatography with a flame ionisation detector (GC-FID and gas chromatography mass spectrophotometry (GC-MS for analysis. Ethylene production and respiration reached a peak on the second and third day of ripening, respectively. Seventy-eight volatile compounds were identified from the pulp of ‘Kesington Pride’ mango; however, only 73 volatile compounds were present in notable amount. The most abundant group of volatile compounds was monoterpenes, accounting for abaout 44% of the total identified compounds, followed by sesquiterpenes (19%, aldehydes (11%,esters (10% aromatics (8%, alcohol (2%, ketones (2%, alkanes (1% and norisoprenoid (1%. -Terpinolene was the major compound during ripening. Except for -pinene, 3,7-dimethl-1,3,7-octatriene, 4-methl-1 (1-methylethylidene-cyclohexene, p-mentha-1,5,8-triene, aloocimene, the concentration of all other monoterpenes increased for the first six or eight days and decreased afterwards. All sesquiteroenes, p-cymene, p-cymen-9-ol,2-ethyl-1,4-dimethl benzene also increased during ripening and peaked on day four, six or eight of ripening. Ketones, aldehydes alkane and cis-3-hexenol, on the other hand, decreased during ripening. Ethanol, esters and norisoprenoid increased quite sharply at the end of ripening period.

  20. Combined in-situ and ex-situ bioremediation of petroleum hydrocarbon contaminated soils by closed-loop soil vapor extraction and air injection

    International Nuclear Information System (INIS)

    Hu, S.S.; Buckler, M.J.

    1993-01-01

    Treatment and restoration of petroleum hydrocarbon contaminated soils at a bulk petroleum above-ground storage tank (AST) site in Michigan is being conducted through in-situ and ex-situ closed-loop soil vapor extraction (SVE), soil vapor treatment, and treated air injection (AI) processes. The soil vapor extraction process applies a vacuum through the petroleum hydrocarbon affected soils in the ex-situ bio-remediation pile (bio-pile) and along the perimeter of excavated area (in-situ area) to remove the volatile or light petroleum hydrocarbons. This process also draws ambient air into the ex-situ bio-pile and in-situ vadose zone soil along the perimeter of excavated area to enhance biodegradation of light and heavy petroleum hydrocarbons in the soil. The extracted soil vapor is treated using a custom-designed air bio-remediation filter (bio-filter) to degrade the petroleum hydrocarbon compounds in the soil vapor extraction air streams. The treated air is then injected into a flush grade soil bed in the backfill area to perform final polishing of the air stream, and to form a closed-loop air flow with the soil vapor extraction perforated pipes along the perimeter of the excavated area

  1. Chemical Cues in Tritrophic Interaction on Biocontrol of Insect Pest

    Directory of Open Access Journals (Sweden)

    Nurindah Nurindah

    2017-03-01

    Full Text Available Tritrophic interaction among host plant-herbivore-parasitoid involves chemical cues. The infested plant by herbivores has been reacted to produce volatiles which is a cue used by the herbivore parasitoids for host location. These volatiles can be developed to enhance natural control of insect pests, especially by optimally use of parasitoids. Egg parasitoids are biocontrol agents that play an important role in natural control of herbivores. This research used a tritrophic interaction model of rice plant-brown plant hopper (BPH-egg parasitoid of BPH. Research on analysis of chemical cues in tritrophic interactions was aimed to identify volatiles that are used by the parasitoid to find its host. The volatiles that effectively affect the parasitoid orientation behavior could be developed into a parasitoid attractant. Extraction of volatiles as the egg parasitoid cues was done using soxhlet, and identification of the volatiles using Gas Chromatography-Mass Spectrometry (GC-MS. Bioassay of the volatiles on the BPH parasitoid orientation behavior was performed using Y-tube olfactometry. The volatiles that are used for host location cues by the parasitoid affect the parasitoid orientation behavior by showing the preference of the parasitoid females to the odor of volatile. Volatiles extracted from BPH-egg-infested plants and uninfested plants contain alcohol, hydrocarbon, and ester compounds. Based on the difference of the compound composition of both extractions, five compounds of long-chain hydrocarbon, both branched and unsaturated compounds are the main volatile components which caused positive orientation behavior of the egg parasitoid. The egg parasitoids showed positive behavior orientation toward the volatiles extracted from BPH-egg-infested plant. Those hydrocarbon compounds are potential materials to be developed into bio attractants of BPH egg parasitoid.

  2. TMVOC, simulator for multiple volatile organic chemicals

    International Nuclear Information System (INIS)

    Pruess, Karsten; Battistelli, Alfredo

    2003-01-01

    TMVOC is a numerical simulator for three-phase non-isothermal flow of water, soil gas, and a multicomponent mixture of volatile organic chemicals (VOCs) in multidimensional heterogeneous porous media. It is an extension of the TOUGH2 general-purpose simulation program developed at the Lawrence Berkeley National Laboratory. TMVOC is designed for applications to contamination problems that involve hydrocarbon fuel or organic solvent spills in saturated and unsaturated zones. It can model contaminant behavior under ''natural'' environmental conditions, as well as for engineered systems, such as soil vapor extraction, groundwater pumping, or steam-assisted source remediation. TMVOC is upwards compatible with T2VOC (Falta et al., 1995) and can be initialized from T2VOC-style initial conditions. The main enhancements in TMVOC relative to T2VOC are as follows: a multicomponent mixture of volatile organic chemicals can be modeled; any and all combinations of the three phases water-oil-gas are treated; several non-condensible gases may be present; diffusion is treated in all phases in a manner that is fully coupled with phase partitioning. This paper gives a brief summary of the methodology used in TMVOC as well as highlighting some implementation issues. Simulation of a NAPL spill and subsequent remediation is discussed for a 2-D vertical section of a saturated-unsaturated flow problem

  3. FIELD SCREENING FOR HALOGENATED VOLATILE ORGANIC COMPOUNDS

    Energy Technology Data Exchange (ETDEWEB)

    John F. Schabron; Joseph F. Rovani Jr.; Theresa M. Bomstad

    2002-06-01

    Western Research Institute (WRI) initiated exploratory work towards the development of new field screening methodology and a test kit to measure halogenated volatile organic compounds (VOCs) in the field. Heated diode and corona discharge sensors are commonly used to detect leaks of refrigerants from air conditioners, freezers, and refrigerators. They are both selective to the presence of carbon-halogen bonds. Commercially available heated diode and corona discharge leak detectors were procured and evaluated for halogenated VOC response. The units were modified to provide a digital readout of signal related to VOC concentration. Sensor response was evaluated with carbon tetrachloride and tetrachloroethylene (perchloroethylene, PCE), which represent halogenated VOCs with and without double bonds. The response characteristics were determined for the VOCs directly in headspace in Tedlar bag containers. Quantitation limits in air were estimated. Potential interferences from volatile hydrocarbons, such as toluene and heptane, were evaluated. The effect of humidity was studied also. The performance of the new devices was evaluated in the laboratory by spiking soil samples and monitoring headspace for halogenated VOCs. A draft concept of the steps for a new analytical method was outlined. The results of the first year effort show that both devices show potential utility for future analytical method development work towards the goal of developing a portable test kit for screening halogenated VOCs in the field.

  4. Formation of diamonds out of hydrocarbon gas in the earth's mantle

    International Nuclear Information System (INIS)

    Krason, J.; Szymanski, A.; Savkevitch, S.S.

    1991-01-01

    This paper discusses the concept of formation of polycrystalline diamonds being discussed dint he context of a very rapid, dynamic decomposition of the hydrocarbon gas, initially biogenic or thermogenic condensed in gas hydrates, naturally locked and highly compressed in the hosting rocks. Gas hydrates are of solid, ice-like composition, mostly of hydrocarbon. Gas hydrates, composed of polyhedral cages, may have two types of structural forms: the body-centered structure or Structure I (small molecules) and diamond lattice or Structure II (large molecules). The crystal structure of the gas hydrate depends on the geometry of gas molecules. The thermodynamic conditions required for stabilization and preservation of the gas hydrates can be changed. Thus, in this concept, the principal source for at least some diamond deposits can originally be highly condensed hydrocarbons. In this case, if all the above indicated thermodynamic conditions and processes are met, naturally precondensed hydrocarbons can be directly converted into polycrystalline, extremely coherent diamonds

  5. Plume composition and volatile flux of Nyamulagira volcano, Democratic Republic of Congo, during birth and evolution of the lava lake, 2014-2015

    Science.gov (United States)

    Bobrowski, N.; Giuffrida, G. B.; Arellano, S.; Yalire, M.; Liotta, M.; Brusca, L.; Calabrese, S.; Scaglione, S.; Rüdiger, J.; Castro, J. M.; Galle, B.; Tedesco, D.

    2017-12-01

    Very little is known about the volatile element makeup of the gaseous emissions of Nyamulagira volcano. This paper tries to fill this gap by reporting the first gas composition measurements of Nyamulagira's volcanic plume since the onset of its lava lake activity at the end of 2014. Two field surveys were carried out on 1 November 2014, and 13-15 October 2015. We applied a broad toolbox of volcanic gas composition measurement techniques in order to geochemically characterize Nyamulagira's plume. Nyamulagira is a significant emitter of SO2, and our measurements confirm this, as we recorded SO2 emissions of up to 14 kt/d during the studied period. In contrast to neighbouring Nyiragongo volcano, however, Nyamulagira exhibits relatively low CO2/SO2 molar ratios ( 92% of total gas emissions). Strong variations in the volatile composition, in particular for the CO2/SO2 ratio, were measured between 2014 and 2015, which appear to reflect the simultaneous variations in volcanic activity. We also determined the molar ratios for Cl/S, F/S and Br/S in the plume gas, finding values of 0.13 and 0.17, 0.06 and 0.11, and 2.3·10-4 and 1·10-4, in 2014 and 2015, respectively. A total gas emission flux of 48 kt/d was estimated for 2014. The I/S ratio in 2015 was found to be 3.6·10-6. In addition, we were able to distinguish between hydrogen halides and non-hydrogen halides in the volcanic plume. Considerable amounts of bromine (18-35% of total bromine) and iodine (8-18% of total iodine) were found in compounds other than hydrogen halides. However, only a negligible fraction of chlorine was found as compounds other than hydrogen chloride.

  6. Chemical investigation of the volatile constituents of Cleome viscosa from Nigeria

    Directory of Open Access Journals (Sweden)

    Gabriel Olatunji

    2005-06-01

    Full Text Available The major volatile constituents of the oils from the integral parts of Cleome viscosa L. from Nigeria have been identified by GC, GC/MS and 1H NMR. The main constituents of the non-polar fraction of the oils were monoterpene hydrocarbons (21% in stem/leaves, 15% in seed/fruits, 12% in roots and some oxygenated derivatives (3% in leaves/stem; 1% in seeds/fruits and 1.5% in roots. The monoterpenes occurred frequently in the oils. Fatty acid esters especially ethyl palmitate which constituted a major constituent in the oil from the seeds/fruits was not detected in the oils from the roots.

  7. Hydrocarbon-degrading sulfate-reducing bacteria in marine hydrocarbon seep sediments

    OpenAIRE

    Kleindienst, Sara

    2012-01-01

    Microorganisms are key players in our biosphere because of their ability to degrade various organic compounds including a wide range of hydrocarbons. At marine hydrocarbon seeps, more than 90% of sulfate reduction (SR) is potentially coupled to non-methane hydrocarbon oxidation. Several hydrocarbon-degrading sulfate-reducing bacteria (SRB) were enriched or isolated from marine sediments. However, in situ active SRB remained largely unknown. In the present thesis, the global distribution and a...

  8. Polycyclic aromatic hydrocarbons - fate and long-range atmospheric transport studied using a global model, EMAC-SVOC

    Science.gov (United States)

    Octaviani, Mega; Tost, Holger; Lammel, Gerhard

    2017-04-01

    Polycyclic aromatic hydrocarbons (PAHs) are emitted by incomplete combustion from fossil fuel, vehicles, and biomass burning. They may persist in environmental compartments, pose a health hazard and may bio accumulate along food chains. The ECHAM/MESSy Atmospheric Chemistry (EMAC) model had been used to simulate global tropospheric, stratospheric chemistry and climate. In this study, we improve the model to include simulations of the transport and fate of semi-volatile organic compounds (SVOC). The EMAC-SVOC model takes into account essential environmental processes including gas-particle partitioning, dry and wet deposition, chemical and bio-degradation, and volatilization from sea surface, soils, vegetation, and snow. The model was evaluated against observational data in the Arctic, mid-latitudes, and tropics, and further applied to study total environmental lifetime and long-range transport potential (LRTP) of PAHs. We selected four compounds for study, spanning a wide range of volatility, i.e., phenanthrene, fluoranthene, pyrene, and benzo[a]pyrene. Several LRTP indicators were investigated, including the Arctic contamination potential, meridional spreading, and zonal and meridional fluxes to remote regions.

  9. Laboratory analytical methods for the determination of the hydrocarbon status of soils (a review)

    Science.gov (United States)

    Pikovskii, Yu. I.; Korotkov, L. A.; Smirnova, M. A.; Kovach, R. G.

    2017-10-01

    Laboratory analytical methods suitable for the determination of the hydrocarbon status of soils (a specific soil characteristic involving information on the total content and qualitative features of soluble (bitumoid) carbonaceous substances and individual hydrocarbons (polycyclic aromatic hydrocarbons, alkanes, etc.) in bitumoid, as well as the composition and content of hydrocarbon gases) have been considered. Among different physicochemical methods of study, attention is focused on the methods suitable for the wide use. Luminescence-bituminological analysis, low-temperature spectrofluorimetry (Shpolskii spectroscopy), infrared (IR) spectroscopy, gas chromatography, chromatography-mass spectrometry, and some other methods have been characterized, as well as sample preparation features. Advantages and limitations of each of these methods are described; their efficiency, instrumental complexity, analysis duration, and accuracy are assessed.

  10. Formaldehyde, methanol and hydrocarbon emissions from methanol-fueled cars

    International Nuclear Information System (INIS)

    Williams, R.L.; Lipari, F.; Potter, R.A.

    1990-01-01

    Exhaust and evaporative emissions tests were conducted on several methanol- and gasoline-fueled vehicles. Separate samples for chromatographic analysis of formaldehyde, methanol, and individual hydrocarbons were collected in each of the three phases of the driving cycle and in each of the two portions of the evaporative emissions test. One vehicle, equipped with an experimental variable-fuel engine, was tested using methanol/gasoline fuel mixtures of 100, 85, 50, 15, and 0 percent methanol. Combustion-generated hydrocarbons were lowest using methanol fuel, and increased several-fold as the gasoline fraction was increased. Gasoline components in the exhaust increased from zero as the gasoline fraction of the fuel was increased. On the other hand, formaldehyde emissions were several times higher using methanol fuel than they were using gasoline. A dedicated methanol car and the variable-fuel car gave similar emissions patterns when they both were tested using methanol fuel. The organic-carbon composition of the exhaust was 85-90 percent methanol, 5-7 percent formaldehyde, and 3-9 percent hydrocarbons. Several cars that were tested using gasoline emitted similar distributions of hydrocarbons, even through the vehicles represented a broad range of current and developmental engine families and emissions control systems

  11. A study of the microbiology and polycyclic aromatic hydrocarbons ...

    African Journals Online (AJOL)

    A study was carried out on the drill cuttings from three different oil and gas wells located at Ologbo Community at Edo State with respect to their microbiology and polycyclic aromatic hydrocarbons (PAHs) compositional profile and sources. Isolation and enumeration of heterotrophic bacteria and fungi was carried out using ...

  12. Distribution of some hydrocarbons in ambient air near Delft and the influence on the formation of secondary air pollutants

    NARCIS (Netherlands)

    Bos, R.; Guicherit, R.; Hoogeveen, A.

    1977-01-01

    The relative concentrations of hydrocarbons in the atmosphere may provide information concerning their origin. It appears that the hydrocarbon composition measured in Delft (The Netherlands) is entirely different for northern and southern wind directions. This points to different sources. The most

  13. Effect of soil application of humic acid on nutrients uptake, essential oil and chemical compositions of garden thyme (Thymus vulgaris L.) under greenhouse conditions.

    Science.gov (United States)

    Noroozisharaf, Alireza; Kaviani, Maryam

    2018-05-01

    Humic acid is natural biological organic, which has a high effect on plant growth and quality. However, the mechanisms of the promoting effect of humic acid on the volatile composition were rarely reported. In this study, the effects of soil application of humic acid on the chemical composition and nutrients uptake of Thymus vulgaris were investigated. Treatments comprised 0, 50, 75 and 100 g m -2 . Essential oil was extracted by hydrodistillation and analyzed using GC-MS and GC-FID. Essential oil content was enhanced by increase of the humic acid level and its content ranged from 0.8% (control) to 2.0% (75 g m -2 ). Thirty-two volatile compounds were identified and these compounds were considerably affected by humic acid. The highest percentage of thymol (74.15%), carvacrol (6.20%), p -cymene (4.24%), borneol (3.42%), trans -caryophyllene (1.70%) and cis -sabinene hydrate (1.35%) as major compounds were observed in T. vulgaris under 100 g m -2 humic acid. There was a linear relationship ( R 2  = 97%) between humic acid levels and thymol as a major compound. The oils were dominated by oxygenated monoterpenes followed by monoterpene hydrocarbons and sesquiterpene hydrocarbons. Based on the path coefficient analysis, the highest direct effects on essential oil content were observed in monoterpene esters (3.465) and oxygenated sesquiterpenes (3.146). The humic acid application also enhanced the uptake of N, P, K, Mg and Fe in garden thyme. The highest N (2.42%), P (0.75%), K (2.63%), Mg (0.23%) and Fe (1436.58 ppm) were observed in medium supplemented with 100 g m -2 humic acid. In all, the utilization of humic acid could positively change nutrients uptake, essential oil content and its major constituents in T. vulgaris .

  14. Chemical Composition, Antioxidant and Antimicrobial Activity of Pericarpium Citri Reticulatae Essential Oil

    Directory of Open Access Journals (Sweden)

    Bei Gao

    2011-05-01

    Full Text Available The chemical composition, antioxidant and antimicrobial activity of Pericarpium Citri Reticulatae (PCR essential oil obtained using an improved Clevenger type apparatus were studied. Among the five different PCRs examined the highest yield of essential oil was found in Chachi 2004 (harvested and stored in 2004 and the lowest in Chachi 2008 (harvested and stored in 2008. Fifty three different volatile compounds were determined, including terpenic hydrocarbons, alcohols, aldehydes, ketones and esters. D-limonene, one of terpenes, was the major constituent in PCR. The antioxidant capacity of PCR essential oil varied considerably with the duration of storage time, and the oil from Chachi 1994 has the strongest ferric-reducing antioxidant power. In addition, the essential oil possessed varying degrees of antimicrobial activity against Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, except Streptococcus faecalis, while had no effect on Gram-negative bacteria (Escherichia coli, Enterobacter cloacae.

  15. Volatile oil composition of Carthamus Tinctorius L. flowers grown in Kazakhstan

    Directory of Open Access Journals (Sweden)

    Aknur Amanbekovna Turgumbayeva

    2018-03-01

    Volatile oil from the flowers of the Kazakhstan safflower species ‘Ak-Mai’ were investigated by GC/MS which allowed the detection of 20 compounds. Biologically active complex of the flower of the Kazakhstan safflower species ‘Ak-Mai’ was released for the first time by using this oil

  16. Diesel-related hydrocarbons can dominate gas phase reactive carbon in megacities

    Directory of Open Access Journals (Sweden)

    R. E. Dunmore

    2015-09-01

    Full Text Available Hydrocarbons are key precursors to two priority air pollutants, ozone and particulate matter. Those with two to seven carbons have historically been straightforward to observe and have been successfully reduced in many developed cities through air quality policy interventions. Longer chain hydrocarbons released from diesel vehicles are not considered explicitly as part of air quality strategies and there are few direct measurements of their gaseous abundance in the atmosphere. This study describes the chemically comprehensive and continuous measurements of organic compounds in a developed megacity (London, which demonstrate that on a seasonal median basis, diesel-related hydrocarbons represent only 20–30 % of the total hydrocarbon mixing ratio but comprise more than 50 % of the atmospheric hydrocarbon mass and are a dominant local source of secondary organic aerosols. This study shows for the first time that 60 % of the winter primary hydrocarbon hydroxyl radical reactivity is from diesel-related hydrocarbons and using the maximum incremental reactivity scale, we predict that they contribute up to 50 % of the ozone production potential in London. Comparing real-world urban composition with regulatory emissions inventories in the UK and US highlights a previously unaccounted for, but very significant, under-reporting of diesel-related hydrocarbons; an underestimation of a factor ~4 for C9 species rising to a factor of over 70 for C12 during winter. These observations show that hydrocarbons from diesel vehicles can dominate gas phase reactive carbon in cities with high diesel fleet fractions. Future control of urban particulate matter and ozone in such locations requires a shift in policy focus onto gas phase hydrocarbons released from diesels as this vehicle type continues to displace gasoline world-wide.

  17. Biogenic volatile organic compounds in the Earth system.

    Science.gov (United States)

    Laothawornkitkul, Jullada; Taylor, Jane E; Paul, Nigel D; Hewitt, C Nicholas

    2009-01-01

    Biogenic volatile organic compounds produced by plants are involved in plant growth, development, reproduction and defence. They also function as communication media within plant communities, between plants and between plants and insects. Because of the high chemical reactivity of many of these compounds, coupled with their large mass emission rates from vegetation into the atmosphere, they have significant effects on the chemical composition and physical characteristics of the atmosphere. Hence, biogenic volatile organic compounds mediate the relationship between the biosphere and the atmosphere. Alteration of this relationship by anthropogenically driven changes to the environment, including global climate change, may perturb these interactions and may lead to adverse and hard-to-predict consequences for the Earth system.

  18. An assessment of the effects of wine volatiles on the perception of taste and astringency in wine

    OpenAIRE

    Sáenz-Navajas, María-Pilar; Campo, Eva; Fernández-Zurbano, Purificación; Valentin, Dominique

    2010-01-01

    The objective of this work is measuring the effect of different volatile extract compositions on the perception of taste, astringency, global intensity and persistence of wine. Six Spanish wines, two from Chardonnay and four from Tempranillo grapes, all of them showing different chemical and sensory characteristics, were selected. Wines were separated into volatile and non-volatile fractions by solid phase extraction and lyophilisation and further liquid extraction, respectively. Eighteen "re...

  19. Solo Mycoremediation Impacted by Waste Hydrocarbons

    Directory of Open Access Journals (Sweden)

    Franklin Santos Freire

    2015-06-01

    Full Text Available Oil and its derivatives are the principal means of energy generation for vehicles that transport raw materials and goods produced in developed and developing regions accentuating the risk of accidents by spills in stockpiling, transport, use or discarding. The contamination by total hydrocarbons suggests the elevated propension to mutations and to the formation of carcinogenic tumors, as a consequence of the exposure to human contamination by these products. This work had as aims: a To investigate, in a laboratorial scale, the degrading capacity of autochthonous microbiota in the presence of differing concentrations of hydrocarbons (0%, 2,5%, 5% e 7,5%; b To isolate fungi tolerant to the contaminant; c To quantify and analyze the biodegradation capacity of soil through the microbial biomass and metabolic quotient; and d To set, in laboratory, ideal conditions of biodegradation of the xenobiotic compound. Some parameters of microbial activity have been evaluated, such as: biological (Carbon of microbial biomass, CO2 , qCO2 emission, and fungi growth, chemical (pH, electrical conductivity –EC –, analysis of fertility and total hydrocarbons and physical (physical composition of the soil for analysis and comparisons. The obtained results suggest that the adding of 5% of waste oil in the ground provided ideal condition for the biodegradation of he   contaminant in the environment. From the evaluated parameters, the emission of CO2 and microbial C were considered more indicative of changes in soil microbial activity subject to the addition of hydrocarbons, confirming the possibility of microremediation use.

  20. Biomass burning contribution to ambient volatile organic compounds (VOCs) in the Chengdu-Chongqing Region (CCR), China

    Science.gov (United States)

    Li, Lingyu; Chen, Yuan; Zeng, Limin; Shao, Min; Xie, Shaodong; Chen, Wentai; Lu, Sihua; Wu, Yusheng; Cao, Wei

    2014-12-01

    Ambient volatile organic compounds (VOCs) were measured intensively using an online gas chromatography-mass spectrometry/flame ionization detector (GC-MS/FID) at Ziyang in the Chengdu-Chongqing Region (CCR) from 6 December 2012 to 4 January 2013. Alkanes contributed the most (59%) to mixing ratios of measured non-methane hydrocarbons (NMHCs), while aromatics contributed the least (7%). Methanol was the most abundant oxygenated VOC (OVOC), contributing 42% to the total amount of OVOCs. Significantly elevated VOC levels occurred during three pollution events, but the chemical composition of VOCs did not differ between polluted and clean days. The OH loss rates of VOCs were calculated to estimate their chemical reactivity. Alkenes played a predominant role in VOC reactivity, among which ethylene and propene were the largest contributors; the contributions of formaldehyde and acetaldehyde were also considerable. Biomass burning had a significant influence on ambient VOCs during our study. We chose acetonitrile as a tracer and used enhancement ratio to estimate the contribution of biomass burning to ambient VOCs. Biomass burning contributed 9.4%-36.8% to the mixing ratios of selected VOC species, and contributed most (>30% each) to aromatics, formaldehyde, and acetaldehyde.

  1. Range-based volatility, expected stock returns, and the low volatility anomaly

    Science.gov (United States)

    2017-01-01

    One of the foundations of financial economics is the idea that rational investors will discount stocks with more risk (volatility), which will result in a positive relation between risk and future returns. However, the empirical evidence is mixed when determining how volatility is related to future returns. In this paper, we examine this relation using a range-based measure of volatility, which is shown to be theoretically, numerically, and empirically superior to other measures of volatility. In a variety of tests, we find that range-based volatility is negatively associated with expected stock returns. These results are robust to time-series multifactor models as well as cross-sectional tests. Our findings contribute to the debate about the direction of the relationship between risk and return and confirm the presence of the low volatility anomaly, or the anomalous finding that low volatility stocks outperform high volatility stocks. In other tests, we find that the lower returns associated with range-based volatility are driven by stocks with lottery-like characteristics. PMID:29190652

  2. Range-based volatility, expected stock returns, and the low volatility anomaly.

    Science.gov (United States)

    Blau, Benjamin M; Whitby, Ryan J

    2017-01-01

    One of the foundations of financial economics is the idea that rational investors will discount stocks with more risk (volatility), which will result in a positive relation between risk and future returns. However, the empirical evidence is mixed when determining how volatility is related to future returns. In this paper, we examine this relation using a range-based measure of volatility, which is shown to be theoretically, numerically, and empirically superior to other measures of volatility. In a variety of tests, we find that range-based volatility is negatively associated with expected stock returns. These results are robust to time-series multifactor models as well as cross-sectional tests. Our findings contribute to the debate about the direction of the relationship between risk and return and confirm the presence of the low volatility anomaly, or the anomalous finding that low volatility stocks outperform high volatility stocks. In other tests, we find that the lower returns associated with range-based volatility are driven by stocks with lottery-like characteristics.

  3. Range-based volatility, expected stock returns, and the low volatility anomaly.

    Directory of Open Access Journals (Sweden)

    Benjamin M Blau

    Full Text Available One of the foundations of financial economics is the idea that rational investors will discount stocks with more risk (volatility, which will result in a positive relation between risk and future returns. However, the empirical evidence is mixed when determining how volatility is related to future returns. In this paper, we examine this relation using a range-based measure of volatility, which is shown to be theoretically, numerically, and empirically superior to other measures of volatility. In a variety of tests, we find that range-based volatility is negatively associated with expected stock returns. These results are robust to time-series multifactor models as well as cross-sectional tests. Our findings contribute to the debate about the direction of the relationship between risk and return and confirm the presence of the low volatility anomaly, or the anomalous finding that low volatility stocks outperform high volatility stocks. In other tests, we find that the lower returns associated with range-based volatility are driven by stocks with lottery-like characteristics.

  4. The Galeta oil spill: Pt. 4

    International Nuclear Information System (INIS)

    Burns, K.A.; Yelle-Simmons, L.

    1994-01-01

    This paper gives the detailed compositions of oil residues in sediments and encrusting bivalves, and the changes over time. Initial weathering processes removed most of the volatile hydrocarbons and all market alkanes in oil adsorbed to surface sediments within 6 months after the spill. This initially fast rate of biodegradation was not maintained in the rate of disappearance of the aromatic hydrocarbons over time. Oil leaching out of heavily contaminated sediments was bioaccumulated in bivalves for at least 5 years. The organisms accumulated the whole range of alkylated polynuclear aromatic hydrocarbons (PAHs) in the naphthalene through the benzoperylene elution range, seemingly in proportion to what was leached from sediments. A change in the composition of the aromatics bioaccumulated at most sites in year 5 indicated depletion of the most soluble and most acutely toxic hydrocarbons in the readily leachable reservoirs. (author)

  5. Hydrocarbon pollutants shape bacterial community assembly of harbor sediments

    KAUST Repository

    Barbato, Marta

    2016-02-02

    Petroleum pollution results in co-contamination by different classes of molecules, entailing the occurrence of marine sediments difficult to remediate, as in the case of the Ancona harbor (Mediterranean Sea, Italy). Autochthonous bioaugmentation (ABA), by exploiting the indigenous microbes of the environment to be treated, could represent a successful bioremediation strategy. In this perspective we aimed to i) identify the main drivers of the bacterial communities\\' richness in the sediments, ii) establish enrichment cultures with different hydrocarbon pollutants evaluating their effects on the bacterial communities\\' composition, and iii) obtain a collection of hydrocarbon degrading bacteria potentially exploitable in ABA. The correlation between the selection of different specialized bacterial populations and the type of pollutants was demonstrated by culture-independent analyses, and by establishing a collection of bacteria with different hydrocarbon degradation traits. Our observations indicate that pollution dictates the diversity of sediment bacterial communities and shapes the ABA potential in harbor sediments.

  6. Detection of radiation-induced hydrocarbons in baked sponged cake prepared with irradiated liquid egg

    Science.gov (United States)

    Schulzki, G.; Spiegelberg, A.; Bögl, K. W.; Schreiber, G. A.

    1995-02-01

    For identification of irradiated food, radiation-induced volatile hydrocarbons (HC) are determined by gas chromatography in the non-polar fraction of fat. However, in complex food matrices the detection is often disturbed by fat-associated compounds. On-line coupling of high performance liquid chromatography (LC) and gas chromatography (GC) is very efficient to remove such compounds from the HC fraction. The high sensitivity of this fast and efficient technique is demonstrated by the example of detection of radiation-induced HC in fat isolated from baked sponge cake which had been prepared with irradiated liquid egg.

  7. Pricing Volatility Referenced Assets

    Directory of Open Access Journals (Sweden)

    Alan De Genaro Dario

    2006-12-01

    Full Text Available Volatility swaps are contingent claims on future realized volatility. Variance swaps are similar instruments on future realized variance, the square of future realized volatility. Unlike a plain vanilla option, whose volatility exposure is contaminated by its asset price dependence, volatility and variance swaps provide a pure exposure to volatility alone. This article discusses the risk-neutral valuation of volatility and variance swaps based on the framework outlined in the Heston (1993 stochastic volatility model. Additionally, the Heston (1993 model is calibrated for foreign currency options traded at BMF and its parameters are used to price swaps on volatility and variance of the BRL / USD exchange rate.

  8. High molecular weight non-polar hydrocarbons as pure model substances and in motor oil samples can be ionized without fragmentation by atmospheric pressure chemical ionization mass spectrometry.

    Science.gov (United States)

    Hourani, Nadim; Kuhnert, Nikolai

    2012-10-15

    High molecular weight non-polar hydrocarbons are still difficult to detect by mass spectrometry. Although several studies have targeted this problem, lack of good self-ionization has limited the ability of mass spectrometry to examine these hydrocarbons. Failure to control ion generation in the atmospheric pressure chemical ionization (APCI) source hampers the detection of intact stable gas-phase ions of non-polar hydrocarbon in mass spectrometry. Seventeen non-volatile non-polar hydrocarbons, reported to be difficult to ionize, were examined by an optimized APCI methodology using nitrogen as the reagent gas. All these analytes were successfully ionized as abundant and intact stable [M-H](+) ions without the use of any derivatization or adduct chemistry and without significant fragmentation. Application of the method to real-life hydrocarbon mixtures like light shredder waste and car motor oil was demonstrated. Despite numerous reports to the contrary, it is possible to ionize high molecular weight non-polar hydrocarbons by APCI, omitting the use of additives. This finding represents a significant step towards extending the applicability of mass spectrometry to non-polar hydrocarbon analyses in crude oil, petrochemical products, waste or food. Copyright © 2012 John Wiley & Sons, Ltd.

  9. [Biodegradability of the components of natural hydrocarbon mixtures previously submitted to landfarming].

    Science.gov (United States)

    Pucci, G N; Pucci, O H

    2003-01-01

    The complex composition of the crude oil and the hydrocarbons that integrate the waste of the different stages of the oil industry turn this product a mixture that presents different difficulties for its elimination by biological methods. The objective of this paper was to study the biodegradation potential of autochthonous bacterial communities on hydrocarbons obtained from four polluted places and subjected to landfarming biorremediation system during a decade. The results showed a marked difference in biodegradability of the three main fractions of crude oil, aliphatic, aromatic, and polar fractions, obtained by column chromatography. All fractions were used as carbon source and energy. There were variations in the production of biomass among the different fractions as well as in the kinetics of biodegradation, according to the composition of each fraction.

  10. Volatile and non-volatile radiolysis products in irradiated multilayer coextruded food-packaging films containing a buried layer of recycled low-density polyethylene.

    Science.gov (United States)

    Chytiri, S; Goulas, A E; Badeka, A; Riganakos, K A; Kontominas, M G

    2005-12-01

    The effects of gamma-irradiation (5-60 kGy) on radiolysis products and sensory changes of experimental five-layer food-packaging films were determined. Films contained a middle buried layer of recycled low-density polyethylene (LDPE) comprising 25-50% by weight (bw) of the multilayer structure. Respective films containing 100% virgin LDPE as the buried layer were used as controls. Under realistic polymer/food simulant contact conditions during irradiation, a large number of primary and secondary radiolysis products (hydrocarbons, aldehydes, ketones, alcohols, carboxylic acids) were produced. These compounds were detected in the food simulant after contact with all films tested, even at the lower absorbed doses of 5 and 10 kGy (approved doses for food preservation). The type and concentration of radiolysis products increased progressively with increasing dose. Generally, there were no significant differences in radiolysis products between samples containing a buried layer of recycled LDPE and those containing virgin LDPE (all absorbed doses), indicating the good barrier properties of external virgin polymer layers. Volatile and non-volatile compounds produced during irradiation affected the sensory properties of potable water after contact with packaging films. Taste transfer to water was observed mainly at higher doses and was more noticeable for multilayer structures containing recycled LDPE, even though differences were slight.

  11. Characterization of a nose-only inhalation exposure system for hydrocarbon mixtures and jet fuels.

    Science.gov (United States)

    Martin, Sheppard A; Tremblay, Raphael T; Brunson, Kristyn F; Kendrick, Christine; Fisher, Jeffrey W

    2010-04-01

    A directed-flow nose-only inhalation exposure system was constructed to support development of physiologically based pharmacokinetic (PBPK) models for complex hydrocarbon mixtures, such as jet fuels. Due to the complex nature of the aerosol and vapor-phase hydrocarbon exposures, care was taken to investigate the chamber hydrocarbon stability, vapor and aerosol droplet compositions, and droplet size distribution. Two-generation systems for aerosolizing fuel and hydrocarbons were compared and characterized for use with either jet fuels or a simple mixture of eight hydrocarbons. Total hydrocarbon concentration was monitored via online gas chromatography (GC). Aerosol/vapor (A/V) ratios, and total and individual hydrocarbon concentrations, were determined using adsorbent tubes analyzed by thermal desorption-gas chromatography-mass spectrometry (TDS-GC-MS). Droplet size distribution was assessed via seven-stage cascade impactor. Droplet mass median aerodynamic diameter (MMAD) was between 1 and 3 mum, depending on the generator and mixture utilized. A/V hydrocarbon concentrations ranged from approximately 200 to 1300 mg/m(3), with between 20% and 80% aerosol content, depending on the mixture. The aerosolized hydrocarbon mixtures remained stable during the 4-h exposure periods, with coefficients of variation (CV) of less than 10% for the total hydrocarbon concentrations. There was greater variability in the measurement of individual hydrocarbons in the A-V phase. In conclusion, modern analytical chemistry instruments allow for improved descriptions of inhalation exposures of rodents to aerosolized fuel.

  12. Impact of starter cultures and fermentation techniques on the volatile aroma and sensory profile of chocolate

    DEFF Research Database (Denmark)

    Crafack, Michael; Keul, Hanna; Eskildsen, Carl Emil Aae

    2014-01-01

    cultures on the formation of flavour precursors, composition of volatile aroma compounds and sensory profile was investigated in cocoa inoculated with cultures encompassing a highly aromatic strain of Pichia kluyveri or a pectinolytic strain of Kluyveromyces marxianus, and compared to commercially...... fermented heap and tray cocoa. Although only minor differences in the concentration of free amino acids and reducing sugars was measured, identification and quantification by dynamic headspace gas chromatography-mass spectrometry (HS/GC-MS) revealed pronounced differences in the composition of volatiles...... in roasted cocoa liquors and finished chocolates. 19 of the 56 volatile compounds identified in the chocolates were found in significantly higher amounts in the tray fermented sample, whilst significantly higher amounts of 2-methoxyphenol was measured in the two inoculated chocolates. The P. kluyveri...

  13. Quantitative estimates of the volatility of ambient organic aerosol

    Directory of Open Access Journals (Sweden)

    C. D. Cappa

    2010-06-01

    high and variable ΔHvap assumptions. Our results also show that the amount of semivolatile gas-phase organics in equilibrium with the OA could range from ~20% to 400% of the OA mass, with smaller values generally corresponding to the higher ΔHvap assumptions. The volatility of various OA components determined from factor analysis of AMS spectra has also been assessed. In general, it is found that the fraction of non-volatile material follows the pattern: biomass burning OA < hydrocarbon-like OA < semivolatile oxygenated OA < low-volatility oxygenated OA. Correspondingly, the sensitivity to dilution and the estimated amount of semivolatile gas-phase material for the OA factors follows the reverse order. Primary OA has a substantial semivolatile fraction, in agreement with previous results, while the non-volatile fraction appears to be dominated by oxygenated OA produced by atmospheric aging. The overall OA volatility is thus controlled by the relative contribution of each aerosol type to the total OA burden. Finally, the model/measurement comparison appears to require OA having an evaporation coefficient (γe substantially greater than 10−2; at this point it is not possible to place firmer constraints on γe based on the observations.

  14. Diffusivity measurements of volatile organics in levitated viscous aerosol particles

    Directory of Open Access Journals (Sweden)

    S. Bastelberger

    2017-07-01

    Full Text Available Field measurements indicating that atmospheric secondary organic aerosol (SOA particles can be present in a highly viscous, glassy state have spurred numerous studies addressing low diffusivities of water in glassy aerosols. The focus of these studies is on kinetic limitations of hygroscopic growth and the plasticizing effect of water. In contrast, much less is known about diffusion limitations of organic molecules and oxidants in viscous matrices. These may affect atmospheric chemistry and gas–particle partitioning of complex mixtures with constituents of different volatility. In this study, we quantify the diffusivity of a volatile organic in a viscous matrix. Evaporation of single particles generated from an aqueous solution of sucrose and small amounts of volatile tetraethylene glycol (PEG-4 is investigated in an electrodynamic balance at controlled relative humidity (RH and temperature. The evaporative loss of PEG-4 as determined by Mie resonance spectroscopy is used in conjunction with a radially resolved diffusion model to retrieve translational diffusion coefficients of PEG-4. Comparison of the experimentally derived diffusivities with viscosity estimates for the ternary system reveals a breakdown of the Stokes–Einstein relationship, which has often been invoked to infer diffusivity from viscosity. The evaporation of PEG-4 shows pronounced RH and temperature dependencies and is severely depressed for RH ≲ 30 %, corresponding to diffusivities < 10−14 cm2 s−1 at temperatures < 15 °C. The temperature dependence is strong, suggesting a diffusion activation energy of about 300 kJ mol−1. We conclude that atmospheric volatile organic compounds can be subject to severe diffusion limitations in viscous organic aerosol particles. This may enable an important long-range transport mechanism for organic material, including pollutant molecules such as polycyclic aromatic hydrocarbons (PAHs.

  15. High bacterial biodiversity increases degradation performance of hydrocarbons during bioremediation of contaminated harbor marine sediments

    International Nuclear Information System (INIS)

    Dell'Anno, Antonio; Beolchini, Francesca; Rocchetti, Laura; Luna, Gian Marco; Danovaro, Roberto

    2012-01-01

    We investigated changes of bacterial abundance and biodiversity during bioremediation experiments carried out on oxic and anoxic marine harbor sediments contaminated with hydrocarbons. Oxic sediments, supplied with inorganic nutrients, were incubated in aerobic conditions at 20 °C and 35 °C for 30 days, whereas anoxic sediments, amended with organic substrates, were incubated in anaerobic conditions at the same temperatures for 60 days. Results reported here indicate that temperature exerted the main effect on bacterial abundance, diversity and assemblage composition. At higher temperature bacterial diversity and evenness increased significantly in aerobic conditions, whilst decreased in anaerobic conditions. In both aerobic and anaerobic conditions, biodegradation efficiencies of hydrocarbons were significantly and positively related with bacterial richness and evenness. Overall results presented here suggest that bioremediation strategies, which can sustain high levels of bacterial diversity rather than the selection of specific taxa, may significantly increase the efficiency of hydrocarbon degradation in contaminated marine sediments. - Highlights: ► Bioremediation performance was investigated on hydrocarbon contaminated sediments. ► Major changes in bacterial diversity and assemblage composition were observed. ► Temperature exerted the major effect on bacterial assemblages. ► High bacterial diversity increased significantly biodegradation performance. ► This should be considered for sediment remediation by bio-treatments. - Bioremediation strategies which can sustain high levels of bacterial diversity may significantly increase the biodegradation of hydrocarbons in contaminated marine sediments.

  16. Natural and anthropogenic hydrocarbon inputs to sediments of Patos Lagoon Estuary, Brazil.

    Science.gov (United States)

    Medeiros, Patricia Matheus; Bícego, Márcia Caruso; Castelao, Renato Menezes; Del Rosso, Clarissa; Fillmann, Gilberto; Zamboni, Ademilson Josemar

    2005-01-01

    The Patos Lagoon Estuary, southern Brazil, is an area of environmental interest not only because of tourism, but also because of the presence of the second major port of Brazil, with the related industrial and shipping activities. Thus, potential hydrocarbon pollution was examined in this study. Sediment samples were collected at 10 sites in the estuary, extracted, and analyzed by GC-FID and GC-MS for composition and concentration of the following organic geochemical markers: normal and isoprenoid alkanes, petroleum biomarkers, linear alkylbenzenes (LABs), and polycyclic aromatic hydrocarbons (PAHs). The total concentrations varied from 1.1 to 129.6 microg g(-1) for aliphatic hydrocarbons, from 17.8 to 4510.6 ng g(-1) for petroleum biomarkers, from 3.2 to 1601.9 ng g(-1) for LABs, and from 37.7 to 11,779.9 ng g(-1) for PAHs. Natural hydrocarbons were mainly derived from planktonic inputs due to a usual development of blooms in the estuary. Terrestrial plant wax compounds prevailed at sites located far from Rio Grande City and subject to stronger currents. Anthropogenic hydrocarbons are related to combustion/pyrolysis processes of fossil fuel, release of unburned oil products and domestic/industrial waste outfalls. Anthropogenic hydrocarbon inputs were more apparent at sites associated with industrial discharges (petroleum distributor and refinery), shipping activities (dry docking), and sewage outfalls (sewage). The overall concentrations of anthropogenic hydrocarbons revealed moderate to high hydrocarbon pollution in the study area.

  17. Purification of iodine-containing mixtures and compositions useful therefor

    International Nuclear Information System (INIS)

    Cobb, R.L.

    1987-01-01

    This patent describes a process for the preparation by distillation of essentially colorless hydrocarbon product substantially free of color-forming impurities, which process comprises: (a) adding 0.02 to 0.10 wt% of a metal, M, to a solution comprising: (i) a hydrocarbon product having 8-30 carbon atoms, and (ii) at least one color-forming impurity selected from the group consisting of: I/sub 2/, and R-I, wherein R is H or an organic radical having 1-30 carbon atoms, inclusive. The color-forming impurity and the metal interact under distillation conditions form a complex, MI/sub n/, where n is equal to the valence of the metal M, and the complex MI/sub n/ is non-volatile and essentially non-decomposable under distillation conditions; (b) subjecting the resulting mixture to distillation conditions; and (c) recovering essentially colorless hydrocarbon product as the overhead fraction from the distillation

  18. Volatile and non-volatile/semi-volatile compounds and in vitro bioactive properties of Chilean Ulmo (Eucryphia cordifolia Cav.) honey.

    Science.gov (United States)

    Acevedo, Francisca; Torres, Paulina; Oomah, B Dave; de Alencar, Severino Matias; Massarioli, Adna Prado; Martín-Venegas, Raquel; Albarral-Ávila, Vicenta; Burgos-Díaz, César; Ferrer, Ruth; Rubilar, Mónica

    2017-04-01

    Ulmo honey originating from Eucryphia cordifolia tree, known locally in the Araucania region as the Ulmo tree is a natural product with valuable nutritional and medicinal qualities. It has been used in the Mapuche culture to treat infections. This study aimed to identify the volatile and non-volatile/semi-volatile compounds of Ulmo honey and elucidate its in vitro biological properties by evaluating its antioxidant, antibacterial, antiproliferative and hemolytic properties and cytotoxicity in Caco-2 cells. Headspace volatiles of Ulmo honey were isolated by solid-phase microextraction (SPME); non-volatiles/semi-volatiles were obtained by removing all saccharides with acidified water and the compounds were identified by GC/MS analysis. Ulmo honey volatiles consisted of 50 compounds predominated by 20 flavor components. Two of the volatile compounds, lyrame and anethol have never been reported before as honey compounds. The non-volatile/semi-volatile components of Ulmo honey comprised 27 compounds including 13 benzene derivatives accounting 75% of the total peak area. Ulmo honey exhibited weak antioxidant activity but strong antibacterial activity particularly against gram-negative bacteria and methicillin-resistant Staphylococcus aureus (MRSA), the main strain involved in wounds and skin infections. At concentrations >0.5%, Ulmo honey reduced Caco-2 cell viability, released lactate dehydrogenase (LDH) and increased reactive oxygen species (ROS) production in a dose dependent manner in the presence of foetal bovine serum (FBS). The wide array of volatile and non-volatile/semi-volatile constituents of Ulmo honey rich in benzene derivatives may partly account for its strong antibacterial and antiproliferative properties important for its therapeutic use. Our results indicate that Ulmo honey can potentially inhibit cancer growth at least partly by modulating oxidative stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. SHS-produced intermetallides as catalysts for hydrocarbons synthesis from CO and H{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Eliseev, O.L.; Kazantsev, R.V.; Davydov, P.E.; Lapidus, A.L. [Russian Academy of Sciences, Moscow (Russian Federation). N.D. Zelinsky Institute of Organic Chemistry; Borshch, V.N.; Pugacheva, E.V. [Russian Academy of Sciences, Chernogolovka (Russian Federation). Inst. of Structural Macrokinetics and Materials Science

    2012-07-01

    Raney-type polymetallic alloys were prepared by Self-Propagating High-Temperature Synthesis followed by alkaline treating. Surface morphology and composition of were studied using XRD, BET, SEM and EMPA techniques. The samples were tested in Fischer-Tropsch synthesis demonstrated rather high activity and very high selectivity to heavy paraffins. High selectivity to C{sub 5+} hydrocarbons is attributed to high thermal conductivity of alloys which prevents hot spots formation and therefore suppresses formation of methane and light hydrocarbons. Selectivity can be further improved by adding some d-metals in catalyst composition. Promotion with La seems to be particularly suitable for lowering methane formation while doping with Ni enhances methane yield greatly. (orig.)

  20. Study of hydrocarbons in bottom sediments of the northern Dvina River-White Sea geochemical barrier during spring flood. Volume 2

    International Nuclear Information System (INIS)

    Nemirovskaya, I.; Shevchenko, V.

    2007-01-01

    The Northern Dvina in Northern Russia is the main river of the White Sea reservoir. The water discharge is 108 km 3 per year. With active shipping and several large pulp and paper mills that operate in the region, the river is a supplier of polluting substances. Weathered oil and pyrogenic compounds dominate the composition of hydrocarbons. During flooding, the Northern Dvina - Dvina Bay geochemical barrier becomes a filter, which prevents pollutants from penetrating to the White Sea. This paper summarized data on the concentration and composition of hydrocarbons, aliphatic hydrocarbons (AHC) and polycyclic aromatic hydrocarbons (PAH) in the marine water and bottom sediments at the mouth of the Northern Dvina/White Sea. Nearly similar concentrations of organic compounds were found in the Northern Dvina River water and in the near-mouth White Sea water area. However, their distribution conforms to the marginal filter rules. Natural terrigenous hydrocarbon compounds were found to dominate in all forms. Biogenic autochthonous hydrocarbons were detected in the near-shore areas and in the outer zone of the marginal filter of the Northern Dvina River, where PAH are formed together with AHC. 20 refs., 2 tabs., 4 figs

  1. Simulation of radioelement volatility during the vitrification of radioactive wastes by arc plasma.

    Science.gov (United States)

    Ghiloufi, Imed

    2009-04-15

    A computer model is used to simulate the volatility of some radioelements cesium ((137)Cs), cobalt ((60)Co), and ruthenium ((106)Ru) during the radioactive wastes vitrification by thermal plasma. This model is based on the calculation of system composition using the free enthalpy minimization method, coupled with the equation of mass transfer at the reactional interface. The model enables the determination of the effects of various parameters (e.g., temperature, plasma current, and matrix composition) on the radioelement volatility. The obtained results indicate that any increase in molten bath temperature causes an increase in the cobalt volatility; while ruthenium has a less obvious behavior. It is also found that the oxygen flux in the carrier gas supports the radioelement incorporations in the containment matrix, except in the case of the ruthenium which is more volatile under an oxidizing atmosphere. For electrolyses effects, an increase in the plasma current considerably increases both the vaporization speed and the vaporized quantities of (137)Cs and (60)Co. The increase of silicon percentage in the containment matrix supports the incorporation of (60)Co and (137)Cs in the matrix. The simulation results are compared favorably to the experimental measurements obtained by emission spectroscopy.

  2. Bioaccumulation of petroleum hydrocarbons in arctic amphipods in the oil development area of the Alaskan Beaufort Sea.

    Science.gov (United States)

    Neff, Jerry M; Durell, Gregory S

    2012-04-01

    An objective of a multiyear monitoring program, sponsored by the US Department of the Interior, Bureau of Ocean Energy Management was to examine temporal and spatial changes in chemical and biological characteristics of the Arctic marine environment resulting from offshore oil exploration and development activities in the development area of the Alaskan Beaufort Sea. To determine if petroleum hydrocarbons from offshore oil operations are entering the Beaufort Sea food web, we measured concentrations of hydrocarbons in tissues of amphipods, Anonyx nugax, sediments, Northstar crude oil, and coastal peat, collected between 1999 and 2006 throughout the development area. Mean concentrations of polycyclic aromatic hydrocarbons (PAH), saturated hydrocarbons (SHC), and sterane and triterpane petroleum biomarkers (StTr) were not significantly different in amphipods near the Northstar oil production facility, before and after it came on line in 2001, and in amphipods from elsewhere in the study area. Forensic analysis of the profiles (relative composition and concentrations) of the 3 hydrocarbon classes revealed that hydrocarbon compositions were different in amphipods, surface sediments where the amphipods were collected, Northstar crude oil, and peat from the deltas of 4 North Slope rivers. Amphipods and sediments contained a mixture of petrogenic, pyrogenic, and biogenic PAH. The SHC in amphipods were dominated by pristane derived from zooplankton, indicating that the SHC were primarily from the amphipod diet of zooplankton detritus. The petroleum biomarker StTr profiles did not resemble those in Northstar crude oil. The forensic analysis revealed that hydrocarbons in amphipod tissues were not from oil production at Northstar. Hydrocarbons in amphipod tissues were primarily from their diet and from river runoff and coastal erosion of natural diagenic and fossil terrestrial materials, including seep oils, kerogens, and peat. Offshore oil and gas exploration and development

  3. Source Signature of Volatile Organic Compounds (VOCs) associated with oil and natural gas operations in Utah and Colorado

    Science.gov (United States)

    Gilman, J.; Lerner, B. M.; Warneke, C.; Holloway, J. S.; Peischl, J.; Ryerson, T. B.; Young, C. J.; Edwards, P.; Brown, S. S.; Wolfe, D. E.; Williams, E. J.; De Gouw, J. A.

    2012-12-01

    The U.S. Energy Information Administration has reported a sharp increase in domestic oil and natural gas production from "unconventional" reserves (e.g., shale and tight sands) between 2005 and 2012. The recent growth in drilling and fossil fuel production has led to environmental concerns regarding local air quality. Severe wintertime ozone events (greater than 100 ppb ozone) have been observed in Utah's Uintah Basin and Wyoming's Upper Green River Basin, both of which contain large natural gas fields. Raw natural gas is a mixture of approximately 60-95 mole percent methane while the remaining fraction is composed of volatile organic compounds (VOCs) and other non-hydrocarbon gases. We measured an extensive set of VOCs and other trace gases near two highly active areas of oil and natural gas production in Utah's Uintah Basin and Colorado's Denver-Julesburg Basin in order to characterize primary emissions of VOCs associated with these industrial operations and identify the key VOCs that are precursors for potential ozone formation. UBWOS (Uintah Basin Winter Ozone Study) was conducted in Uintah County located in northeastern Utah in January-February 2012. Two Colorado studies were conducted at NOAA's Boulder Atmospheric Observatory in Weld County in northeastern Colorado in February-March 2011 and July-August 2012 as part of the NACHTT (Nitrogen, Aerosol Composition, and Halogens on a Tall Tower) and SONNE (Summer Ozone Near Natural gas Emissions) field experiments, respectively. The C2-C6 hydrocarbons were greatly enhanced for all of these studies. For example, the average propane mixing ratio observed during the Utah study was 58 ppb (median = 35 ppb, minimum = 0.8, maximum = 520 ppb propane) compared to urban averages which range between 0.3 and 6.0 ppb propane. We compare the ambient air composition from these studies to urban measurements in order to show that the VOC source signature from oil and natural gas operations is distinct and can be clearly

  4. Iodine volatility

    International Nuclear Information System (INIS)

    Beahm, E.C.; Shockley, W.E.

    1984-01-01

    The ultimate aim of this program is to couple experimental aqueous iodine volatilities to a fission product release model. Iodine partition coefficients, for inorganic iodine, have been measured during hydrolysis and radiolysis. The hydrolysis experiments have illustrated the importance of reaction time on iodine volatility. However, radiolysis effects can override hydrolysis in determining iodine volatility. In addition, silver metal in radiolysis samples can react to form silver iodide accompanied by a decrease in iodine volatility. Experimental data are now being coupled to an iodine transport and release model that was developed in the Federal Republic of Germany

  5. Methane and Benzene in Drinking-Water Wells Overlying the Eagle Ford, Fayetteville, and Haynesville Shale Hydrocarbon Production Areas.

    Science.gov (United States)

    McMahon, Peter B; Barlow, Jeannie R B; Engle, Mark A; Belitz, Kenneth; Ging, Patricia B; Hunt, Andrew G; Jurgens, Bryant C; Kharaka, Yousif K; Tollett, Roland W; Kresse, Timothy M

    2017-06-20

    Water wells (n = 116) overlying the Eagle Ford, Fayetteville, and Haynesville Shale hydrocarbon production areas were sampled for chemical, isotopic, and groundwater-age tracers to investigate the occurrence and sources of selected hydrocarbons in groundwater. Methane isotopes and hydrocarbon gas compositions indicate most of the methane in the wells was biogenic and produced by the CO 2 reduction pathway, not from thermogenic shale gas. Two samples contained methane from the fermentation pathway that could be associated with hydrocarbon degradation based on their co-occurrence with hydrocarbons such as ethylbenzene and butane. Benzene was detected at low concentrations (2500 years, indicating the benzene was from subsurface sources such as natural hydrocarbon migration or leaking hydrocarbon wells. One sample contained benzene that could be from a surface release associated with hydrocarbon production activities based on its age (10 ± 2.4 years) and proximity to hydrocarbon wells. Groundwater travel times inferred from the age-data indicate decades or longer may be needed to fully assess the effects of potential subsurface and surface releases of hydrocarbons on the wells.

  6. Fusarium oxysporum volatiles enhance plant growth via affecting auxin transport and signaling

    Directory of Open Access Journals (Sweden)

    Vasileios eBitas

    2015-11-01

    Full Text Available Volatile organic compounds (VOCs have well-documented roles in plant-plant communication and directing animal behavior. In this study, we examine the less understood roles of VOCs in plant-fungal relationships. Phylogenetically and ecologically diverse strains of Fusarium oxysporum, a fungal species complex that often resides in the rhizosphere of assorted plants, produce volatile compounds that augment shoot and root growth of Arabidopsis thaliana and tobacco. Growth responses of A. thaliana hormone signaling mutants and expression patterns of a GUS reporter gene under the auxin-responsive DR5 promoter supported the involvement of auxin signaling in F. oxysporum volatile-mediated growth enhancement. In addition, 1-naphthylthalamic acid, an inhibitor of auxin efflux, negated F. oxysporum volatile-mediated growth enhancement in both plants. Comparison of the profiles of volatile compounds produced by F. oxysporum strains that differentially affected plant growth suggests that the relative compositions of both growth inhibitory and stimulatory compounds may determine the degree of plant growth enhancement. Volatile-mediated signaling between fungi and plants may represent a potentially conserved, yet mostly overlooked, mechanism underpinning plant-fungus interactions and fungal niche adaption.

  7. Biogenic non-methane hydrocarbons (NMHC). Nature`s contribution to regional and global atmospheric chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Klockow, D.; Hoffman, T. [Inst. of Spectrochemistry and Applied Spectroscopy, Dortmund (Germany)

    1995-12-31

    Terrestrial vegetation provides an important source of volatile hydrocarbons, especially isoprene, monoterpenes and in addition possibly sesquiterpenes as well as oxygenated compounds. Although there exist considerable uncertainties in the estimation of the magnitude of these biogenic NMHC emissions, it is generally accepted that the majority of global NMHC release is from natural and not from anthropogenic sources. Taking into consideration the high reactivity of the mostly unsaturated biogenic emissions, their impact on tropospheric processes can be assumed to be of great importance. Together with anthropogenic NO{sub x} emissions, the highly reactive natural alkenes can act as precursors in photochemical oxidant formation and contribute to regional-scale air pollution. Their oxidation in the atmosphere and the subsequent gas-to-particle conversion of the products lead to the formation of organic aerosols. Because of the formation of phytotoxic compounds, the interaction of the biogenic hydrocarbons with ozone inside or outside the leaves and needles of plants has been suggested to play a role in forest decline. (author)

  8. Biogenic non-methane hydrocarbons (NMHC). Nature`s contribution to regional and global atmospheric chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Klockow, D; Hoffman, T [Inst. of Spectrochemistry and Applied Spectroscopy, Dortmund (Germany)

    1996-12-31

    Terrestrial vegetation provides an important source of volatile hydrocarbons, especially isoprene, monoterpenes and in addition possibly sesquiterpenes as well as oxygenated compounds. Although there exist considerable uncertainties in the estimation of the magnitude of these biogenic NMHC emissions, it is generally accepted that the majority of global NMHC release is from natural and not from anthropogenic sources. Taking into consideration the high reactivity of the mostly unsaturated biogenic emissions, their impact on tropospheric processes can be assumed to be of great importance. Together with anthropogenic NO{sub x} emissions, the highly reactive natural alkenes can act as precursors in photochemical oxidant formation and contribute to regional-scale air pollution. Their oxidation in the atmosphere and the subsequent gas-to-particle conversion of the products lead to the formation of organic aerosols. Because of the formation of phytotoxic compounds, the interaction of the biogenic hydrocarbons with ozone inside or outside the leaves and needles of plants has been suggested to play a role in forest decline. (author)

  9. Sampling of high molecular weight hydrocarbons with adsorbent tubes

    International Nuclear Information System (INIS)

    Stroemberg, B.

    1996-12-01

    Adsorption tubes have been used to determine the content of hydrocarbons in gas samples from small scale combustion and gasification of biomass. Compounds from benzene (mw 78) to indeno (1,2,3-cd) pyrene (mw 276) have been examined. The results show that it is possible to analyze polyaromatic hydrocarbons (PAH) with 4 aromatic rings (mw 202). Detection limits for these compounds are 3 . PAH with higher molecule weight can be identified and quantified in samples with high amounts of PAH e.g. at gasification of biomass. Sampling on adsorption tubes is extremely quick and easy. The tube is inserted in the gas of interest and the sample is sucked through the tube with a pump. Sampling times of 2-10 minutes are often sufficient. High moisture content in the gas may result in losses of the most volatile compounds, when drying. Even very low concentrations of water in the tube may cause ice formation in the cold-trap and the sample will be destroyed. The analysis is unfortunately time-consuming because the desorption oven must be cooled between every analysis. This will reduce the number of samples which can be analyzed per day. The tubes can be stored for several weeks before analysis without deterioration. 4 refs, 5 figs, 3 tabs

  10. Study of Volatile Components of Acacia farnesiana Willd . Flowers

    Directory of Open Access Journals (Sweden)

    Papaefthimiou Evangelia

    2017-09-01

    Full Text Available The chemical composition of the essential oil and the absolute of five populations of Acacia farnesiana, cultivated in Greece, have been investigated. The saturated hydrocarbons tricosane, nonadecane and heneicosane, along with methyl salicylate, characterized the chemical analysis of the essential oils and the absolutes, while hexadecanoic acid and α -amyrine were important constituents of some absolutes.

  11. The applicability of radiotracers for the investigation of the distillation of hydrocarbons

    International Nuclear Information System (INIS)

    Graczyk, J.; Iller, E.

    1976-01-01

    The use of radioactive tracers provide valuable methods for the investigation of distillation processes and have been applied to determine the characteristics of material streams, the dynamics of flowing phases and the composition in various parts of the distillation equipment. A method is proposed for testing individual radiotracers emplozemployed for the investigation of the distillation of hydrocarbons. The method consists in laboratory-scale distillation of a tracer together with a multicomponent hydrocarbon mixture, namely a gasoline fraction. The purification efficiency, distillation characteristics, and effective radiochemical purity of several tracers (reactor activated bromobenzene and synthesized C 3 H 7 82 Br, C 4 H 9 82 Br, C 5 H 11 82 Br) have been investigated. The distillation characteristics of bromohydrocarbons labelled with 82 Br and selected hydrocarbons tagged with 14 C (benzene and cumene) have been compared. The radiotracers investigated were employed for the determination of the hydrodynamic parameters of hydrocarbon distillation in laboratory packed columns and a commercial distillation tower. (author)

  12. Sediment-associated aliphatic and aromatic hydrocarbons in coastal British Columbia, Canada: Concentrations, composition, and associated risks to protected sea otters

    International Nuclear Information System (INIS)

    Harris, Kate A.; Yunker, Mark B.; Dangerfield, Neil; Ross, Peter S.

    2011-01-01

    Sediment-associated hydrocarbons can pose a risk to wildlife that rely on benthic marine food webs. We measured hydrocarbons in sediments from the habitat of protected sea otters in coastal British Columbia, Canada. Alkane concentrations were dominated by higher odd-chain n-alkanes at all sites, indicating terrestrial plant inputs. While remote sites were dominated by petrogenic polycyclic aromatic hydrocarbons (PAHs), small harbour sites within sea otter habitat and sites from an urban reference area reflected weathered petroleum and biomass and fossil fuel combustion. The partitioning of hydrocarbons between sediments and adjacent food webs provides an important exposure route for sea otters, as they consume ∼25% of their body weight per day in benthic invertebrates. Thus, exceedences of PAH sediment quality guidelines designed to protect aquatic biota at 20% of the sites in sea otter habitat suggest that sea otters are vulnerable to hydrocarbon contamination even in the absence of catastrophic oil spills. - Highlights: → Sediment hydrocarbon signatures differed between remote and impacted coastal sites. → A natural background comprised terrestrial plant alkanes and petrogenic PAHs. → Impacted sites reflected a history of petrogenic and pyrogenic hydrocarbon inputs. → Hydrocarbons at some sites exceeded guidelines for the protection of aquatic life. → Protected sea otters may thus be at risk as they rely primarily on benthic prey. - Anthropogenically-derived hydrocarbons in coastal sediments in British Columbia may pose a risk to protected sea otters.

  13. Effect of sugars on liquid-vapour partition of volatile compounds in ready-to-drink coffee beverages.

    Science.gov (United States)

    Piccone, P; Lonzarich, V; Navarini, L; Fusella, G; Pittia, P

    2012-09-01

    The effect of sugars (sucrose, lactose, glucose, fructose, 10%w/v) on the liquid-vapour partition of selected volatile compounds of coffee beverages has been investigated in espresso coffee and ready-to-drink (RTD) canned coffee prepared and obtained by using the same Arabica roasted coffee beans blend. Aroma composition of coffee beverages has been preliminary investigated by headspace-gas chromatography (HS-GC) and solid phase microextraction-HS-GC-mass spectrometry to characterize the volatile pattern of the systems and to evaluate the effects of sugars on the aroma release/retention. Then, the liquid-vapour partition coefficient (k) of 4 selected key aroma compounds (diacetyl, 2,3-pentanedione, ethylpyrazine, hexanal) was determined in water, sugars solutions as well as RTD coffee brews added with the same sugars (10%w/v). Sugars added in coffee beverages affected the release of the volatiles and thus its aroma profile with differences due to the type of added sugar and coffee brew type. The k values of the selected volatile compounds resulted different depending on the model system composition (water, coffee brew) and sugar type added. In particular, melanoidins as well as other non-volatile components (lipids, acids, carbohydrates) in the RTD coffee brews could be implied in the change of k of the volatile compounds in respect to that observed in water. The effects of the sugar type on the release/retention of the four key coffee aroma compounds were partly explained in terms of 'salting out' especially for the more polar volatile compounds and in the sucrose-added model systems. The change of chemical and physico-chemical properties of the water and brews induced by the sugars as well as the occurrence of interactions between volatile compounds and non-volatile components may be implied in the reduction of the vapour partition of the aroma compounds. Copyright © 2012 John Wiley & Sons, Ltd.

  14. Composition and location of volatiles at Loki Patera, Io

    Science.gov (United States)

    Howell, Robert R.; Landis, Claire E.; Lopes, Rosaly M. C.

    2014-02-01

    Volatiles play a critical role in determining the nature of volcanic activity on Earth, but their role in the volcanism on Io is less clear. To help determine that role we analyze Voyager and Galileo images of Loki Patera. Loki is the largest caldera in the Solar System and Io’s most powerful volcano, however its eruptive behavior is still not understood. It appears to be relatively volatile poor, in comparison to other sites like Pele where volatiles drive a 350 km high plume. A resurfacing wave, either from spreading flows or from foundering of a lava lake crust, periodically sweeps around Loki Patera. Photometry from Voyager I and II violet and blue images shows that most of the features in and around Loki have colors well matched by macroscopic mixing of sulfur and basalt. The dark western portion of the patera has the color of bare basalt. Assuming such a macroscopic sulfur-basalt mix, in the Voyager I images most of the rest of the patera appears to be covered with a background of 13-38% sulfur. We infer this background sulfur was deposited from the nearby plume observed by Voyager I and II. The surface of the patera is also dotted by numerous small bright areas which have colloquially been called “bergs”. We find that they are also composed of sulfur, with coverage ranging up to 100%. Darker regions adjacent to the patera, such as the “southwest overflow”, are a mixture of intermediate amounts of sulfur and basalt. The “bathtub ring” at the edge of the overflow is again roughly 100% sulfur, perhaps with significant amounts of SO2 included. Colors seen during the Voyager II flyby are also consistent with this general pattern, but most of the patera has a sulfur abundance higher than that seen in Voyager I, while the then-dark southern portion is again close to the reflectance of bare basalt. We have also analyzed the spatial distribution of the bergs. They clearly avoid the inner and outer margins of the patera, and they also avoid each other

  15. Relationships between volatile compounds and sensory characteristics in virgin olive oil by analytical and chemometric approaches.

    Science.gov (United States)

    Procida, Giuseppe; Cichelli, Angelo; Lagazio, Corrado; Conte, Lanfranco S

    2016-01-15

    The volatile fraction of virgin olive oil is characterised by low molecular weight compounds that vaporise at room temperature. In order to obtain an aroma profile similar to natural olfactory perception, the composition of the volatile compounds was determined by applying dynamic headspace gas chromatography, performed at room temperature, with a cryogenic trap directly connected to a gas chromatograph-mass spectrometer system. Samples were also evaluated according to European Union and International Olive Council official methods for sensory evaluation. In this paper, the composition of the volatile fraction of 25 extra virgin olive oils from different regions of Italy was analysed and some preliminary considerations on relationships between chemical composition of volatile fraction and sensory characteristics are reported. Forty-two compounds were identified by means of the particular analytical technique used. All the analysed samples, classified as extra virgin by the panel test, never present peaks whose magnitude is important enough in defected oils. The study was focused on the evaluation of volatile compounds responsible for the positive impact on olive odour properties ('green-fruity' and 'sweet') and olfactory perception. Chemometric evaluation of data, obtained through headspace analysis and the panel test evaluation, showed a correlation between chemical compounds and sensory properties. On the basis of the results, the positive attributes of virgin olive oil are divided into two separated groups: sweet types or green types. Sixteen volatile compounds with known positive impact on odour properties were extracted and identified. In particular, eight compounds seem correlated with sweet properties whereas the green sensation appears to be correlated with eight other different substances. The content of the compounds at six carbon atoms proves to be very important in defining positive attributes of extra virgin olive oils and sensory evaluation. © 2015

  16. Volatile compounds analysis of Dacia sausage, a traditional Romanian dry cured sausage

    Directory of Open Access Journals (Sweden)

    Ana Maria SIMION CIUCIU

    2014-12-01

    Full Text Available Three batches of Dacia sausage were produced as follows: one without starter culture and two with a mix of starter cultures. Volatiles were extracted by a purgeand- trap method and analyzed by gas chromatographic/mass spectrometry. Approximately 43 compounds were identified. The substances identified belong to: aldehydes, alcohols, ketones, hydrocarbons, esters, acids, furans. Results indicated that the most abundant class of chemical substances in flavor at the end of the ripening process was esters, followed by aldehydes, hydrocarbures and terpenes. This could only indicate the high microbial esterification activity that took place in the batches. It was possible to differentiate between the three sausages applying a discriminant analysis.

  17. Associations of Volatile Compounds with Sensory Aroma and Flavor: The Complex Nature of Flavor

    Directory of Open Access Journals (Sweden)

    Edgar Chambers IV

    2013-04-01

    Full Text Available Attempts to relate sensory analysis data to specific chemicals such as volatile compounds have been frequent. Often these associations are difficult to interpret or are weak in nature. Although some difficulties may relate to the methods used, the difficulties also result from the complex nature of flavor. For example, there are multiple volatiles responsible for a flavor sensation, combinations of volatiles yield different flavors than those expected from individual compounds, and the differences in perception of volatiles in different matrices. This review identifies some of the reasons sensory analysis and instrumental measurements result in poor associations and suggests issues that need to be addressed in future research for better understanding of the relationships of flavor/aroma phenomena and chemical composition.

  18. Electro-volatilization of ruthenium in nitric medium: influences of ruthenium species nature and models solutions composition

    International Nuclear Information System (INIS)

    Mousset, F.

    2004-12-01

    Ruthenium is one of the fission products in the reprocessing of irradiated fuels that requires a specific processing management. Its elimination, upstream by the PUREX process, has been considered. A process, called electro-volatilization, which take advantage of the RuO 4 volatility, has been optimised in the present study. It consists in a continuous electrolysis of ruthenium solutions in order to generate RuO 4 species that is volatilized and easily trapped. This process goes to satisfying ruthenium elimination yields with RuNO(NO 3 ) 3 (H 2 O) 2 synthetic solutions but not with fuel dissolution solutions. Consequently, this work consisted in the speciation studies of dissolved ruthenium species were carried out by simulating fuel solutions produced by hot acid attack of several ruthenium compounds (Ru(0), RuO 2 ,xH 2 O, polymetallic alloy). In parallel with dissolution kinetic studies, the determination of dissolved species was performed using voltammetry, spectrometry and spectro-electrochemistry. The results showed the co-existence of Ru(IV) and RuNO(NO 2 ) 2 (H 2 O) 3 . Although these species are different from synthetic RuNO(NO 3 ) 3 (H 2 O) 2 , their electro-oxidation behaviour are similar. The electro-volatilization tests of these dissolution solutions yielded to comparable results as the synthetic RuNO(NO 3 ) 3 (H 2 O) 2 solutions. Then, complexity increase of models solutions was performed by in-situ generation of nitrous acid during ruthenium dissolution. Nitrous acid showed a catalytic effect on ruthenium dissolution. Its presence goes to quasi exclusively RuNO(NO 2 ) 2 (H 2 O) 3 species. It is also responsible of the strong n-bond formation between Ru 2+ and NO + . In addition, it has been shown that its reducing action on RuO 4 hinders the electro-volatilization process. Mn 2+ and Ce 3+ cations also reveal, but to a lesser extent, an electro-eater behaviour as well as Pu 4+ and Cr 3+ according to the thermodynamics data. These results allow one to

  19. Upgrading of petroleum oil feedstocks using alkali metals and hydrocarbons

    Science.gov (United States)

    Gordon, John Howard

    2014-09-09

    A method of upgrading an oil feedstock by removing heteroatoms and/or one or more heavy metals from the oil feedstock composition. This method reacts the oil feedstock with an alkali metal and an upgradant hydrocarbon. The alkali metal reacts with a portion of the heteroatoms and/or one or more heavy metals to form an inorganic phase separable from the organic oil feedstock material. The upgradant hydrocarbon bonds to the oil feedstock material and increases the number of carbon atoms in the product. This increase in the number of carbon atoms of the product increases the energy value of the resulting oil feedstock.

  20. Differences in the fragrances of pollen, leaves, and floral parts of garland (Chrysanthemum coronarium) and composition of the essential oils from flowerheads and leaves.

    Science.gov (United States)

    Flamini, Guido; Cioni, Pier Luigi; Morelli, Ivano

    2003-04-09

    Headspace analyses of pollen, whole flowerheads, ligulate and tubular florets, flower buds, involucral bracts, and leaves have been performed on the food plant Chrysanthemum coronarium L. (Asteraceae). The analyses permitted differences in the pattern of volatiles emitted by the different floral parts to be observed and the site and phenological stage of emission of these chemicals to be verified. Camphor and cis-chrysanthenyl acetate were emitted mainly by ligulate and tubular florets; the production of myrcene and (Z)-ocimene was higher in the flower buds, whereas beta-caryophyllene, (E,E)-alpha-farnesene, and (E)-beta-farnesene seemed attributable mainly to the involucral bracts. The leaves showed a quite different volatile profile, with (Z)-ocimene as the main constituent. Pollen showed a completely different composition of its volatiles, with perilla aldehyde, cis-chrysanthenyl acetate, and camphor among the principal compounds; many carbonylic compounds and linear hydrocarbons have been detected exclusively in pollen. Furthermore, the essential oils obtained from flowerheads and leaves have been studied. These samples showed mainly quantitative differences. Camphor (22.1%) and cis-chrysanthenyl acetate (19.9%) were the main constituents of the oil from flowers, whereas the oil from the leaves contained mainly (Z)-ocimene (45.4%) and myrcene (28.2%).