Sample records for organic compounds annual

  1. Atmospheric Chemistry of Micrometeoritic Organic Compounds

    NASA Technical Reports Server (NTRS)

    Kress, M. E.; Belle, C. L.; Pevyhouse, A. R.; Iraci, L. T.

    2011-01-01

    Micrometeorites approx.100 m in diameter deliver most of the Earth s annual accumulation of extraterrestrial material. These small particles are so strongly heated upon atmospheric entry that most of their volatile content is vaporized. Here we present preliminary results from two sets of experiments to investigate the fate of the organic fraction of micrometeorites. In the first set of experiments, 300 m particles of a CM carbonaceous chondrite were subject to flash pyrolysis, simulating atmospheric entry. In addition to CO and CO2, many organic compounds were released, including functionalized benzenes, hydrocarbons, and small polycyclic aromatic hydrocarbons. In the second set of experiments, we subjected two of these compounds to conditions that simulate the heterogeneous chemistry of Earth s upper atmosphere. We find evidence that meteor-derived compounds can follow reaction pathways leading to the formation of more complex organic compounds.

  2. Source apportionment of airborne particulate matter using organic compounds as tracers

    NASA Astrophysics Data System (ADS)

    Schauer, James J.; Rogge, Wolfgang F.; Hildemann, Lynn M.; Mazurek, Monica A.; Cass, Glen R.; Simoneit, Bernd R. T.

    A chemical mass balance receptor model based on organic compounds has been developed that relates source contributions to airborne fine particle mass concentrations. Source contributions to the concentrations of specific organic compounds are revealed as well. The model is applied to four air quality monitoring sites in southern California using atmospheric organic compound concentration data and source test data collected specifically for the purpose of testing this model. The contributions of up to nine primary particle source types can be separately identified in ambient samples based on this method, and approximately 85% of the organic fine aerosol is assigned to primary sources on an annual average basis. The model provides information on source contributions to fine mass concentrations, fine organic aerosol concentrations and individual organic compound concentrations. The largest primary source contributors to fine particle mass concentrations in Los Angeles are found to include diesel engine exhaust, paved road dust, gasoline-powered vehicle exhaust, plus emissions from food cooking and wood smoke, with smaller contribution from tire dust, plant fragments, natural gas combustion aerosol, and cigarette smoke. Once these primary aerosol source contributions are added to the secondary sulfates, nitrates and organics present, virtually all of the annual average fine particle mass at Los Angeles area monitoring sites can be assigned to its source.

  3. Source apportionment of airborne particulate matter using organic compounds as tracers

    NASA Astrophysics Data System (ADS)

    Schauer, James J.; Rogge, Wolfgang F.; Hildemann, Lynn M.; Mazurek, Monica A.; Cass, Glen R.; Simoneit, Bernd R. T.

    A chemical mass balance receptor model based on organic compounds has been developed that relates sours; contributions to airborne fine particle mass concentrations. Source contributions to the concentrations of specific organic compounds are revealed as well. The model is applied to four air quality monitoring sites in southern California using atmospheric organic compound concentration data and source test data collected specifically for the purpose of testing this model. The contributions of up to nine primary particle source types can be separately identified in ambient samples based on this method, and approximately 85% of the organic fine aerosol is assigned to primary sources on an annual average basis. The model provides information on source contributions to fine mass concentrations, fine organic aerosol concentrations and individual organic compound concentrations. The largest primary source contributors to fine particle mass concentrations in Los Angeles are found to include diesel engine exhaust, paved road dust, gasoline-powered vehicle exhaust, plus emissions from food cooking and wood smoke, with smaller contribution:; from tire dust, plant fragments, natural gas combustion aerosol, and cigarette smoke. Once these primary aerosol source contributions are added to the secondary sulfates, nitrates and organics present, virtually all of the annual average fine particle mass at Los Angeles area monitoring sites can be assigned to its source.

  4. [Detection of organic compounds on Mars].

    PubMed

    Kobayashi, K

    1997-03-01

    McKay et al. detected polycyclic aromatic hydrocarbons (PAHs) in Martian meteorite ALH 84001 by two-step laser mass spectrometry. From the presence of PAHs, together with other results, they concluded that there were past life of Mars. On the other hands, no organisms nor organic compounds were detected in Martian regolith in Viking experiments in 1976. In order to obtain solid evidence for organisms or bioorganic compounds compounds on Mars, further analyses of Martian samples are required. There may be four classes of organic compounds on Mars, which are (i) organic compounds abiotically formed from primitive Mars atmosphere, (ii) Organic compounds delivered out of Mars, (iii) Organic compounds biotically formed by Mars organisms, and (iv) Organic compounds abiotically formed from the present Mars atmosphere. Possible organic compounds on Mars and analytical methods for them are discussed.

  5. Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Cooper, Grorge

    2001-01-01

    Carbonaceous meteorites are relatively enriched in soluble organic compounds. To date, these compounds provide the only record available to study a range of organic chemical processes in the early Solar System chemistry. The Murchison meteorite is the best-characterized carbonaceous meteorite with respect to organic chemistry. The study of its organic compounds has related principally to aqueous meteorite parent body chemistry and compounds of potential importance for the origin of life. Among the classes of organic compounds found in Murchison are amino acids, amides, carboxylic acids, hydroxy acids, sulfonic acids, phosphonic acids, purines and pyrimidines (Table 1). Compounds such as these were quite likely delivered to the early Earth in asteroids and comets. Until now, polyhydroxylated compounds (polyols), including sugars (polyhydroxy aldehydes or ketones), sugar alcohols, sugar acids, etc., had not been identified in Murchison. Ribose and deoxyribose, five-carbon sugars, are central to the role of contemporary nucleic acids, DNA and RNA. Glycerol, a three-carbon sugar alcohol, is a constituent of all known biological membranes. Due to the relative lability of sugars, some researchers have questioned the lifetime of sugars under the presumed conditions on the early Earth and postulated other (more stable) compounds as constituents of the first replicating molecules. The identification of potential sources and/or formation mechanisms of pre-biotic polyols would add to the understanding of what organic compounds were available, and for what length of time, on the ancient Earth.

  6. Organosulfates and organic acids in Arctic aerosols: speciation, annual variation and concentration levels

    NASA Astrophysics Data System (ADS)

    Hansen, A. M. K.; Kristensen, K.; Nguyen, Q. T.; Zare, A.; Cozzi, F.; Nøjgaard, J. K.; Skov, H.; Brandt, J.; Christensen, J. H.; Ström, J.; Tunved, P.; Krejci, R.; Glasius, M.

    2014-08-01

    Sources, composition and occurrence of secondary organic aerosols in the Arctic were investigated at Zeppelin Mountain, Svalbard, and Station Nord, northeastern Greenland, during the full annual cycle of 2008 and 2010, respectively. Speciation of organic acids, organosulfates and nitrooxy organosulfates - from both anthropogenic and biogenic precursors were in focus. A total of 11 organic acids (terpenylic acid, benzoic acid, phthalic acid, pinic acid, suberic acid, azelaic acid, adipic acid, pimelic acid, pinonic acid, diaterpenylic acid acetate and 3-methyl-1,2,3-butanetricarboxylic acid), 12 organosulfates and 1 nitrooxy organosulfate were identified in aerosol samples from the two sites using a high-performance liquid chromatograph (HPLC) coupled to a quadrupole Time-of-Flight mass spectrometer. At Station Nord, compound concentrations followed a distinct annual pattern, where high mean concentrations of organosulfates (47 ± 14 ng m-3) and organic acids (11.5 ± 4 ng m-3) were observed in January, February and March, contrary to considerably lower mean concentrations of organosulfates (2 ± 3 ng m-3) and organic acids (2.2 ± 1 ng m-3) observed during the rest of the year. At Zeppelin Mountain, organosulfate and organic acid concentrations remained relatively constant during most of the year at a mean concentration of 15 ± 4 ng m-3 and 3.9 ± 1 ng m-3, respectively. However during four weeks of spring, remarkably higher concentrations of total organosulfates (23-36 ng m-3) and total organic acids (7-10 ng m-3) were observed. Elevated organosulfate and organic acid concentrations coincided with the Arctic haze period at both stations, where northern Eurasia was identified as the main source region. Air mass transport from northern Eurasia to Zeppelin Mountain was associated with a 100% increase in the number of detected organosulfate species compared with periods of air mass transport from the Arctic Ocean, Scandinavia and Greenland. The results from this

  7. Extraterrestrial Organic Compounds in Meteorites

    NASA Technical Reports Server (NTRS)

    Botta, Oliver; Bada, Jeffrey L.; Meyer, Michael (Technical Monitor)

    2003-01-01

    Many organic compounds or their precursors found in meteorites originated in the interstellar or circumstellar medium and were later incorporated into planetesimals during the formation of the solar system. There they either survived intact or underwent further processing to synthesize secondary products on the meteorite parent body. The most distinct feature of CI and CM carbonaceous chondrites, two types of stony meteorites, is their high carbon content (up to 3% of weight), either in the form of carbonates or of organic compounds. The bulk of the organic carbon consists of an insoluble macromolecular material with a complex structure. Also present is a soluble organic fraction, which has been analyzed by several separation and analytical procedures. Low detection limits can be achieved by derivatization of the organic molecules with reagents that allow for analysis by gas chromatography/mass spectroscopy and high performance liquid chromatography. The CM meteorite Murchison has been found to contain more than 70 extraterrestrial amino acids and several other classes of compounds including carboxylic acids, hydroxy carboxylic acids, sulphonic and phosphonic acids, aliphatic, aromatic and polar hydrocarbons, fullerenes, heterocycles as well as carbonyl compounds, alcohols, amines and amides. The organic matter was found to be enriched in deuterium, and distinct organic compounds show isotopic enrichments of carbon and nitrogen relative to terrestrial matter.

  8. Soil organic carbon quality in forested mineral wetlands at different mean annual temperature.

    Treesearch

    Cinzia Fissore; Christian P. Giardina; Randall K. Kolka; Carl C. Trettin

    2009-01-01

    Forested mineral soil wetlands (FMSW) store large stocks of soil organic carbon (SOC), but little is known on: (i) whether the quality of SOC stored in these soils (proportion of active versus more resistant SOC compounds) differs from SOC in upland soils; (ii) how the quality of SOC in FMSW varies with mean annual temperature (MAT); and (iii) whether SOC decomposition...

  9. The contribution of evaporative emissions from gasoline vehicles to the volatile organic compound inventory in Mexico City.

    PubMed

    Schifter, I; Díaz, L; Rodríguez, R; González-Macías, C

    2014-06-01

    The strategy for decreasing volatile organic compound emissions in Mexico has been focused much more on tailpipe emissions than on evaporative emissions, so there is very little information on the contribution of evaporative emissions to the total volatile organic compound inventory. We examined the magnitudes of exhaust and evaporative volatile organic compound emissions, and the species emitted, in a representative fleet of light-duty gasoline vehicles in the Metropolitan Area of Mexico City. The US "FTP-75" test protocol was used to estimate volatile organic compound emissions associated with diurnal evaporative losses, and when the engine is started and a journey begins. The amount and nature of the volatile organic compounds emitted under these conditions have not previously been accounted in the official inventory of the area. Evaporative emissions from light-duty vehicles in the Metropolitan Area of Mexico City were estimated to be 39 % of the total annual amount of hydrocarbons emitted. Vehicles built before 1992 (16 % of the fleet) were found to be responsible for 43 % of the total hydrocarbon emissions from exhausts and 31 % of the evaporative emissions of organic compounds. The relatively high amounts of volatile organic compounds emitted from older vehicles found in this study show that strong emission controls need to be implemented in order to decrease the contribution of evaporative emissions of this fraction of the fleet.

  10. Possible complex organic compounds on Mars.

    PubMed

    Kobayashi, K; Sato, T; Kajishima, S; Kaneko, T; Ishikawa, Y; Saito, T

    1997-01-01

    It is suggested that primitive Mars had somehow similar environments as primitive Earth. If life was born on the primitive earth using organic compounds which were produced from the early Earth environment, the same types of organic compounds were also formed on primitive Mars. Such organic compounds might have been preserved on Mars still now. We are studying possible organic formation on primitive and present Mars. A gaseous mixture of CO2, CO, N2 and H2O with various mixing ratios were irradiated with high energy protons (major components of cosmic rays). Hydrogen cyanide and formaldehyde were detected among volatile products, and yellow-brown-colored water-soluble non-volatile substances were produced, which gave amino acids after acid-hydrolysis. Major part of "amino acid precursors" were not simple molecules like aminonitriles, but complex compounds which eluted earlier than free amino acids in cation-exchange HPLC. These organic compounds should be major targets in the future Mars mission. Strategy for the detection of the complex organics on Mars will be discussed.

  11. Organic electronic devices using phthalimide compounds

    DOEpatents

    Hassan, Azad M.; Thompson, Mark E.

    2010-09-07

    Organic electronic devices comprising a phthalimide compound. The phthalimide compounds disclosed herein are electron transporters with large HOMO-LUMO gaps, high triplet energies, large reduction potentials, and/or thermal and chemical stability. As such, these phthalimide compounds are suitable for use in any of various organic electronic devices, such as OLEDs and solar cells. In an OLED, the phthalimide compounds may serve various functions, such as a host in the emissive layer, as a hole blocking material, or as an electron transport material. In a solar cell, the phthalimide compounds may serve various functions, such as an exciton blocking material. Various examples of phthalimide compounds which may be suitable for use in the present invention are disclosed.

  12. Organic electronic devices using phthalimide compounds

    DOEpatents

    Hassan, Azad M.; Thompson, Mark E.

    2012-10-23

    Organic electronic devices comprising a phthalimide compound. The phthalimide compounds disclosed herein are electron transporters with large HOMO-LUMO gaps, high triplet energies, large reduction potentials, and/or thermal and chemical stability. As such, these phthalimide compounds are suitable for use in any of various organic electronic devices, such as OLEDs and solar cells. In an OLED, the phthalimide compounds may serve various functions, such as a host in the emissive layer, as a hole blocking material, or as an electron transport material. In a solar cell, the phthalimide compounds may serve various functions, such as an exciton blocking material. Various examples of phthalimide compounds which may be suitable for use in the present invention are disclosed.

  13. Organic electronic devices using phthalimide compounds

    DOEpatents

    Hassan, Azad M.; Thompson, Mark E.

    2013-03-19

    Organic electronic devices comprising a phthalimide compound. The phthalimide compounds disclosed herein are electron transporters with large HOMO-LUMO gaps, high triplet energies, large reduction potentials, and/or thermal and chemical stability. As such, these phthalimide compounds are suitable for use in any of various organic electronic devices, such as OLEDs and solar cells. In an OLED, the phthalimide compounds may serve various functions, such as a host in the emissive layer, as a hole blocking material, or as an electron transport material. In a solar cell, the phthalimide compounds may serve various functions, such as an exciton blocking material. Various examples of phthalimide compounds which may be suitable for use in the present invention are disclosed.

  14. Surface microlayer enrichment of volatile organic compounds and semi-volatile organic compounds in drinking water source.

    PubMed

    Huang, Zhi; Zhou, Wen; Yu, Ya-juan; Zhang, Ai-qian; Han, Shuo-kui; Wang, Lian-sheng

    2004-01-01

    Enrichment of volatile organic compounds(VOC) and semi-volatility organic compounds(SVOC) in surface microlayer(SM) of three drinking water sources were studied. The enrichment factor(EFs) were 0.67 to 13.37 and 0.16 to 136, respectively. The results showed some VOC and most SVOC could enrich in SM. Some EFs of SVOC was quite high. Suspension and temperature could affect EFs of SVOC, slim wind and water movement do not destroy enrichment of organic in SM.

  15. Methods of making organic compounds by metathesis

    DOEpatents

    Abraham, Timothy W.; Kaido, Hiroki; Lee, Choon Woo; Pederson, Richard L.; Schrodi, Yann; Tupy, Michael John

    2015-09-01

    Described are methods of making organic compounds by metathesis chemistry. The methods of the invention are particularly useful for making industrially-important organic compounds beginning with starting compositions derived from renewable feedstocks, such as natural oils. The methods make use of a cross-metathesis step with an olefin compound to produce functionalized alkene intermediates having a pre-determined double bond position. Once isolated, the functionalized alkene intermediate can be self-metathesized or cross-metathesized (e.g., with a second functionalized alkene) to produce the desired organic compound or a precursor thereto. The method may be used to make bifunctional organic compounds, such as diacids, diesters, dicarboxylate salts, acid/esters, acid/amines, acid/alcohols, acid/aldehydes, acid/ketones, acid/halides, acid/nitriles, ester/amines, ester/alcohols, ester/aldehydes, ester/ketones, ester/halides, ester/nitriles, and the like.

  16. Method and reaction pathway for selectively oxidizing organic compounds

    DOEpatents

    Camaioni, Donald M.; Lilga, Michael A.

    1998-01-01

    A method of selectively oxidizing an organic compound in a single vessel comprises: a) combining an organic compound, an acid solution in which the organic compound is soluble, a compound containing two oxygen atoms bonded to one another, and a metal ion reducing agent capable of reducing one of such oxygen atoms, and thereby forming a mixture; b) reducing the compound containing the two oxygen atoms by reducing one of such oxygen atoms with the metal ion reducing agent to, 1) oxidize the metal ion reducing agent to a higher valence state, and 2) produce an oxygen containing intermediate capable of oxidizing the organic compound; c) reacting the oxygen containing intermediate with the organic compound to oxidize the organic compound into an oxidized organic intermediate, the oxidized organic intermediate having an oxidized carbon atom; d) reacting the oxidized organic intermediate with the acid counter ion and higher valence state metal ion to bond the acid counter ion to the oxidized carbon atom and thereby produce a quantity of an ester incorporating the organic intermediate and acid counter ion; and e) reacting the oxidized organic intermediate with the higher valence state metal ion and water to produce a quantity of alcohol which is less than the quantity of ester, the acid counter ion incorporated in the ester rendering the carbon atom bonded to the counter ion less reactive with the oxygen containing intermediate in the mixture than is the alcohol with the oxygen containing intermediate.

  17. Organic compounds in radiation fogs in Davis (California)

    NASA Astrophysics Data System (ADS)

    Herckes, Pierre; Hannigan, Michael P.; Trenary, Laurie; Lee, Taehyoung; Collett, Jeffrey L.

    New stainless steel active fogwater collectors were designed and used in Davis (CA, USA) to collect fogwater for the speciation of organic matter. Organic compounds in fog samples were extracted by liquid-liquid extraction and analyzed by gas chromatography coupled to mass spectrometry. Numerous organic compounds, including various alkanes, polycyclic aromatic hydrocarbons (PAH) and alkanoic acids, have been identified in the fogwater samples. Higher molecular weight (MW) compounds are preferentially associated with an insoluble phase inside the fog drops, whereas lower molecular weight and more polar compounds are found predominantly in the dissolved phase. Concentrations in the dissolved phase were sometimes much higher than estimated by the compounds' aqueous solubilities.

  18. Organic compounds in the Murchison meteorite.

    NASA Technical Reports Server (NTRS)

    Ponnamperuma, C.

    1972-01-01

    Impressive supporting evidence for the concept of the chemical evolution of life has appeared in the discovery of biologically important compounds in extraterrestrial samples. The approaches pursued to detect extraterrestrial organic compounds include the study of interstellar space by radioastronomy, the evaluation of the Apollo lunar samples, and the analysis of meteorites, both ancient and recent. It has been found that the clouds of gas in the interstellar medium contain a wide variety of molecules, most of which are organic in nature. The carbonaceous chondrites contain polymeric organic matter. Amino acids have been detected in the Murchison meteorite.

  19. Removal of organic compounds from shale gas flowback water.

    PubMed

    Butkovskyi, Andrii; Faber, Ann-Hélène; Wang, Yue; Grolle, Katja; Hofman-Caris, Roberta; Bruning, Harry; Van Wezel, Annemarie P; Rijnaarts, Huub H M

    2018-07-01

    Ozonation, sorption to granular activated carbon and aerobic degradation were compared as potential treatment methods for removal of dissolved organic carbon (DOC) fractions and selected organic compounds from shale gas flowback water after pre-treatment in dissolved air flotation unit. Flowback water was characterised by high chemical oxygen demand and DOC. Low molecular weight (LMW) acids and neutral compounds were the most abundant organic fractions, corresponding to 47% and 35% of DOC respectively. Ozonation did not change distribution of organic carbon fractions and concentrations of detected individual organic compounds significantly. Sorption to activated carbon targeted removal of individual organic compounds with molecular weight >115 Da, whereas LMW compounds remained largely unaffected. Aerobic degradation was responsible for removal of LMW compounds and partial ammonium removal, whereas formation of intermediates with molecular weight of 200-350 Da was observed. Combination of aerobic degradation for LMW organics removal with adsorption to activated carbon for removal of non-biodegradable organics is proposed to be implemented between pre-treatment (dissolved air floatation) and desalination (thermal or membrane desalination) steps. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Reflectance spectroscopy of organic compounds: 1. Alkanes

    NASA Astrophysics Data System (ADS)

    Clark, Roger N.; Curchin, John M.; Hoefen, Todd M.; Swayze, Gregg A.

    2009-03-01

    Reflectance spectra of the organic compounds comprising the alkane series are presented from the ultraviolet to midinfrared, 0.35 to 15.5 μm. Alkanes are hydrocarbon molecules containing only single carbon-carbon bonds, and are found naturally on the Earth and in the atmospheres of the giant planets and Saturn's moon, Titan. This paper presents the spectral properties of the alkanes as the first in a series of papers to build a spectral database of organic compounds for use in remote sensing studies. Applications range from mapping the environment on the Earth, to the search for organic molecules and life in the solar system and throughout the universe. We show that the spectral reflectance properties of organic compounds are rich, with major diagnostic spectral features throughout the spectral range studied. Little to no spectral change was observed as a function of temperature and only small shifts and changes in the width of absorption bands were observed between liquids and solids, making remote detection of spectral properties throughout the solar system simpler. Some high molecular weight organic compounds contain single-bonded carbon chains and have spectra similar to alkanes even when they fall into other families. Small spectral differences are often present allowing discrimination among some compounds, further illustrating the need to catalog spectral properties for accurate remote sensing identification with spectroscopy.

  1. Reflectance spectroscopy of organic compounds: 1. Alkanes

    USGS Publications Warehouse

    Clark, R.N.; Curchin, J.M.; Hoefen, T.M.; Swayze, G.A.

    2009-01-01

    Reflectance spectra of the organic compounds comprising the alkane series are presented from the ultraviolet to midinfrared, 0.35 to 15.5 /??m. Alkanes are hydrocarbon molecules containing only single carbon-carbon bonds, and are found naturally on the Earth and in the atmospheres of the giant planets and Saturn's moon, Titan. This paper presents the spectral properties of the alkanes as the first in a series of papers to build a spectral database of organic compounds for use in remote sensing studies. Applications range from mapping the environment on the Earth, to the search for organic molecules and life in the solar system and throughout the. universe. We show that the spectral reflectance properties of organic compounds are rich, with major diagnostic spectral features throughout the spectral range studied. Little to no spectral change was observed as a function of temperature and only small shifts and changes in the width of absorption bands were observed between liquids and solids, making remote detection of spectral properties throughout the solar system simpler. Some high molecular weight organic compounds contain single-bonded carbon chains and have spectra similar to alkanes even ' when they fall into other families. Small spectral differences are often present allowing discrimination among some compounds, further illustrating the need to catalog spectral properties for accurate remote sensing identification with spectroscopy.

  2. Catalyst for Oxidation of Volatile Organic Compounds

    NASA Technical Reports Server (NTRS)

    Wood, George M. (Inventor); Upchurch, Billy T. (Inventor); Schryer, David R. (Inventor); Davis, Patricia P. (Inventor); Kielin, Erik J. (Inventor); Brown, Kenneth G. (Inventor); Schyryer, Jacqueline L. (Inventor); DAmbrosia, Christine M. (Inventor)

    2000-01-01

    Disclosed is a process for oxidizing volatile organic compounds to carbon dioxide and water with the minimal addition of energy. A mixture of the volatile organic compound and an oxidizing agent (e.g. ambient air containing the volatile organic compound) is exposed to a catalyst which includes a noble metal dispersed on a metal oxide which possesses more than one oxidation state. Especially good results are obtained when the noble metal is platinum, and the metal oxide which possesses more than one oxidation state is tin oxide. A promoter (i.e., a small amount of an oxide of a transition series metal) may be used in association with the tin oxide to provide very beneficial results.

  3. PERFLUORINATED ORGANIC COMPOUND EXPOSURE ASSESSMENT RESEARCH

    EPA Science Inventory

    A wide range of perfluorinated organic compounds (PFCs) has been used in a variety of industrial processes and consumer products. The most commonly studied PFCs include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but there are many more compounds in this c...

  4. VOLATILE ORGANIC COMPOUNDS (VOCS) CHAPTER 31.

    EPA Science Inventory

    The term "volatile organic compounds' (VOCs) was originally coined to refer, as a class, to carbon-containing chemicals that participate in photochemical reactions in the ambient (outdoor) are. The regulatory definition of VOCs used by the U.S. EPA is: Any compound of carbon, ex...

  5. TEMPORAL VARIABILITY MEASUREMENT OF SPECIFIC VOLATILE ORGANIC COMPOUNDS

    EPA Science Inventory

    Methodology was developed to determine unambiguously trace levels of volatile organic compounds as they vary in concentration over a variety of time scales. his capability is important because volatile organic compounds (VOCs) are usually measure by time-integrative techniques th...

  6. Oceanic protection of prebiotic organic compounds from UV radiation

    NASA Technical Reports Server (NTRS)

    Cleaves, H. J.; Miller, S. L.; Bada, J. L. (Principal Investigator)

    1998-01-01

    It is frequently stated that UV light would cause massive destruction of prebiotic organic compounds because of the absence of an ozone layer. The elevated UV flux of the early sun compounds this problem. This applies to organic compounds of both terrestrial and extraterrestrial origin. Attempts to deal with this problem generally involve atmospheric absorbers. We show here that prebiotic organic polymers as well as several inorganic compounds are sufficient to protect oceanic organic molecules from UV degradation. This aqueous protection is in addition to any atmospheric UV absorbers and should be a ubiquitous planetary phenomenon serving to increase the size of planetary habitable zones.

  7. Trace organic compounds in wet atmospheric deposition: an overview

    USGS Publications Warehouse

    Steinheimer, T.R.; Johnson, S.M.

    1987-01-01

    An overview of the occurrence of organic compounds in wet atmospheric deposition is given. Multiplicity of sources and problems associated with source identification are discussed. Available literature is reviewed by using citations from Chemical Abstracts and Water Resources Abstracts through June 1985 and includes reports published through December 1984 that summarize current knowledge. Approaches to the chemical determination of organic compounds in precipitation are examined in addition to aspects of sampling protocols. Best methods for sample collection and preparation for instrumental analysis continue to be discussed among various investigators. Automatic wet-deposition-only devices for collection and extraction are preferred. Classes of organic compounds that have been identified in precipitation include a spectrum of compounds with differing properties of acidity or basicity, polarity, and water solubility. Those compounds that have been reported in rainfall, snowfall, and ice include hydrocarbons (both aromatic and nonaromatic), chlorinated derivatives of these hydrocarbons, carbonyl compounds (both acidic and nonacidic), and carboxylic acids and esters. Formic and acetic are the most abundant organic acids present. Cloudwater, fogwater, and mist also have been collected and analyzed for organic composition.

  8. Improving rubber concrete by waste organic sulfur compounds.

    PubMed

    Chou, Liang-Hisng; Lin, Chun-Nan; Lu, Chun-Ku; Lee, Cheng-Haw; Lee, Maw-Tien

    2010-01-01

    In this study, the use of crumb tyres as additives to concrete was investigated. For some time, researchers have been studying the physical properties of concrete to determine why the inclusion of rubber particles causes the concrete to degrade. Several methods have been developed to improve the bonding between rubber particles and cement hydration products (C-S-H) with the hope of creating a product with an improvement in mechanical strength. In this study, the crumb tyres were treated with waste organic sulfur compounds from a petroleum refining factory in order to modify their surface properties. Organic sulfur compounds with amphiphilic properties can enhance the hydrophilic properties of the rubber and increase the intermolecular interaction forces between rubber and C-S-H. In the present study, a colloid probe of C-S-H was prepared to measure these intermolecular interaction forces by utilizing an atomic force microscope. Experimental results showed that rubber particles treated with waste organic sulfur compounds became more hydrophilic. In addition, the intermolecular interaction forces increased with the adsorption of waste organic sulfur compounds on the surface of the rubber particles. The compressive, tensile and flexural strengths of concrete samples that included rubber particles treated with organic sulfur compound also increased significantly.

  9. Evolution of interstellar organic compounds under asteroidal hydrothermal conditions

    NASA Astrophysics Data System (ADS)

    Vinogradoff, V.; Bernard, S.; Le Guillou, C.; Remusat, L.

    2018-05-01

    Carbonaceous chondrites (CC) contain a diversity of organic compounds. No definitive evidence for a genetic relationship between these complex organic molecules and the simple organic molecules detected in the interstellar medium (ISM) has yet been reported. One of the many difficulties arises from the transformations of organic compounds during accretion and hydrothermal alteration on asteroids. Here, we report results of hydrothermal alteration experiments conducted on a common constituent of interstellar ice analogs, Hexamethylenetetramine (HMT - C6H12N4). We submitted HMT to asteroidal hydrothermal conditions at 150 °C, for various durations (up to 31 days) and under alkaline pH. Organic products were characterized by gas chromatography mass spectrometry, infrared spectroscopy and synchrotron-based X-ray absorption near edge structure spectroscopy. Results show that, within a few days, HMT has evolved into (1) a very diverse suite of soluble compounds dominated by N-bearing aromatic compounds (> 150 species after 31 days), including for instance formamide, pyridine, pyrrole and their polymers (2) an aromatic and N-rich insoluble material that forms after only 7 days of experiment and then remains stable through time. The reaction pathways leading to the soluble compounds likely include HMT dissociation, formose and Maillard-type reactions, e.g. reactions of sugar derivatives with amines. The present study demonstrates that, if interstellar organic compounds such as HMT had been accreted by chondrite parent bodies, they would have undergone chemical transformations during hydrothermal alteration, potentially leading to the formation of high molecular weight insoluble organic molecules. Some of the diversity of soluble and insoluble organic compounds found in CC may thus result from asteroidal hydrothermal alteration.

  10. Molybdenum compounds in organic synthesis

    NASA Astrophysics Data System (ADS)

    Khusnutdinov, R. I.; Oshnyakova, T. M.; Dzhemilev, U. M.

    2017-02-01

    The review presents the first analysis and systematic discussion of data published in the last 35-40 years on the use of molybdenum compounds and complexes in organic synthesis and catalysis of various ion coordination and radical reactions. Detailed account is given of the key trends in the use of molybdenum complexes as catalysts of alkene epoxidation and oxyketonation, oxidation of sulfur, nitrogen and phosphorus compounds, hydrosilylation of 1,3-dienes, ketones and aldehydes, hydrostannylation of acetylenes and hydrogermylation of norbornadienes. Considerable attention is paid to the description of new reactions and in situ generation of highly reactive hypohalites, ROX and HOX, induced by molybdenum complexes and the use of hypohalites in oxidative transformations. Data on the application of molybdenum complexes in well-known reactions are discussed, including Kharasch and Pauson-Khand reactions, allylic alkylation of C-nucleophiles, aminocarbonylation of halo derivatives and oligomerization of cyclic dienes, trienes, alkynes and 1,3-dienes. The last Section of the review considers 'unusual' organic reactions involving molybdenum compounds and complexes. The bibliography includes 257 references.

  11. GROUNDWATER TRANSPORT OF HYDROPHOBIC ORGANIC COMPOUNDS IN THE PRESENCE OF DISSOLVED ORGANIC MATTER

    EPA Science Inventory

    The effects of dissolved organic matter (DOM) on the transport of hydrophobic organic compounds in soil columns were investigated. Three compounds (naphthalene, phenanthrene and DDT) that spanned three orders of magnitude in water solubility were used. Instead of humic matter, mo...

  12. Highly elevated atmospheric levels of volatile organic compounds in the Uintah Basin, Utah.

    PubMed

    Helmig, D; Thompson, C R; Evans, J; Boylan, P; Hueber, J; Park, J-H

    2014-05-06

    Oil and natural gas production in the Western United States has grown rapidly in recent years, and with this industrial expansion, growing environmental concerns have arisen regarding impacts on water supplies and air quality. Recent studies have revealed highly enhanced atmospheric levels of volatile organic compounds (VOCs) from primary emissions in regions of heavy oil and gas development and associated rapid photochemical production of ozone during winter. Here, we present surface and vertical profile observations of VOC from the Uintah Basin Winter Ozone Studies conducted in January-February of 2012 and 2013. These measurements identify highly elevated levels of atmospheric alkane hydrocarbons with enhanced rates of C2-C5 nonmethane hydrocarbon (NMHC) mean mole fractions during temperature inversion events in 2013 at 200-300 times above the regional and seasonal background. Elevated atmospheric NMHC mole fractions coincided with build-up of ambient 1-h ozone to levels exceeding 150 ppbv (parts per billion by volume). The total annual mass flux of C2-C7 VOC was estimated at 194 ± 56 × 10(6) kg yr(-1), equivalent to the annual VOC emissions of a fleet of ∼100 million automobiles. Total annual fugitive emission of the aromatic compounds benzene and toluene, considered air toxics, were estimated at 1.6 ± 0.4 × 10(6) and 2.0 ± 0.5 × 10(6) kg yr(-1), respectively. These observations reveal a strong causal link between oil and gas emissions, accumulation of air toxics, and significant production of ozone in the atmospheric surface layer.

  13. Palladium catalyzed hydrogenation of bio-oils and organic compounds

    DOEpatents

    Elliott, Douglas C [Kennewick, WA; Hu, Jianli [Richland, WA; Hart,; Todd, R [Kennewick, WA; Neuenschwander, Gary G [Burbank, WA

    2011-06-07

    The invention provides palladium-catalyzed hydrogenations of bio-oils and certain organic compounds. Experimental results have shown unexpected and superior results for palladium-catalyzed hydrogenations of organic compounds typically found in bio-oils.

  14. Palladium catalyzed hydrogenation of bio-oils and organic compounds

    DOEpatents

    Elliott, Douglas C [Richland, WA; Hu, Jianli [Kennewick, WA; Hart, Todd R [Kennewick, WA; Neuenschwander, Gary G [Burbank, WA

    2008-09-16

    The invention provides palladium-catalyzed hydrogenations of bio-oils and certain organic compounds. Experimental results have shown unexpected and superior results for palladium-catalyzed hydrogenations of organic compounds typically found in bio-oils.

  15. Volatile and semivolatile organic compounds in laboratory ...

    EPA Pesticide Factsheets

    Speciated volatile organic compounds (VOCs) and organic fine particulate matter (PM2.5) mass emission factors were determined from laboratory peat fire experiments. Peat samples originated from two wildlife reserves located near the coast of North Carolina, U.S. Gas and particulate organics were quantified by gas chromatography/mass spectrometry and by high pressure liquid chromatography. Hazardous air pollutants (HAPs) accounted for a large fraction (~60 %) of the speciated VOC emissions from peat burning, including large contributions of acetaldehyde, formaldehyde, benzene, toluene, and chloromethane. Speciated organic PM2.5 mass was dominated by the following compound classes: organic acids, levoglucosan, n-alkanes, and n-alkenes. Emission factors for PM2.5 organic acids including n-alkanoic acids, n-alkenoic acids, n-alkanedioic acids, and aromatic acids were reported for the first time for peat burning, representing the largest fraction of organic carbon (OC) mass (11-12 %) of all speciated compound classes measured in this work. Levoglucosan contributed 2-3 % of the OC mass, while methoxyphenols represented 0.2-0.3 % of the OC mass on a carbon mass basis. Retene was the most abundant particulate phase polycyclic aromatic hydrocarbon. Total HAP VOC and particulate polycyclic aromatic hydrocarbon emissions from a 2008 peat wildfire in North Carolina were estimated, suggesting that peat fires can contribute a large fraction of state-wide HAP emissions. This p

  16. A method of isolating organic compounds present in water

    NASA Technical Reports Server (NTRS)

    Calder, G. V.; Fritz, J.; Junk, G. A.

    1972-01-01

    Water sample is passed through a column containing macroreticular resin, which absorbs only nonionic organic compounds. These compounds are selectively separated using aqueous eluents of varying pH, or completely exuded with small amount of an organic eluent.

  17. Photochemical dimerization of organic compounds

    DOEpatents

    Crabtree, Robert H.; Brown, Stephen H.; Muedas, Cesar A.; Ferguson, Richard R.

    1992-01-01

    At least one of selectivity and reaction rate of photosensitized vapor phase dimerizations, including dehydrodimerizations, hydrodimerizations and cross-dimerizations of saturated and unsaturated organic compounds is improved by conducting the dimerization in the presence of hydrogen or nitrous oxide.

  18. (CHINA) PERFLUORINATED ORGANIC COMPOUND EXPOSURE ASSESSMENT RESEARCH

    EPA Science Inventory

    A wide range of perfluorinated organic compounds (PFCs) has been used in a variety of industrial processes and consumer products. The most commonly studied PFCs include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but there are many more compounds in this c...

  19. Mechanochemical synthesis of organic compounds and composites with their participation

    NASA Astrophysics Data System (ADS)

    Lyakhov, Nikolai Z.; Grigorieva, Tatiana F.; Barinova, Antonina P.; Vorsina, I. A.

    2010-05-01

    The results of experimental studies in the mechanochemical synthesis of organic compounds and composites with their participation published over the last 15 years are described systematically. The key reactions of organic compounds are considered: synthesis of the salts of organic acids, acylation, substitution, dehalogenation, esterification, hydrometallation and other reactions. Primary attention is devoted to systems and compounds that cannot be obtained by traditional chemistry methods.

  20. Chlorinated organic compounds in urban river sediments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Soma, Y.; Shiraishi, H.; Inaba, K.

    1995-12-31

    Among anthropogenic chemicals, many chlorinated organic compounds have been used as insecticides and detected frequently as contaminants in urban river sediments so far. However, the number and total amount of chemicals produced commercially and used are increasing year by year, though each amount of chemicals is not so high. New types of contaminants in the environment may be detected by the use of newly developed chemicals. Chlorinated organic compounds in the urban river sediments around Tokyo and Kyoto, large cities in Japan, were surveyed and recent trends of contaminants were studied. Contaminants of the river sediments in industrial areas hadmore » a variety, but PCB (polychlorinated biphenyls) was detected in common in industrial areas. Concentration of PCB related well to the number of factories on both sides of rivers, although the use of PCB was stopped 20 years ago. In domestic areas, Triclosan (5-chloro-2-(2,4-dichlorophenoxy)-phenol) and Triclocarban (3,4,4{prime}-trichlorocarbanilide)(both are contained in soap or shampoo for fungicides), p-dichlorobenzene (insecticides for wears) and TCEP(tris-chloroethyl phosphate) were detected. EOX(extracted organic halogen) in the sediments was 5 to 10 times of chlorinated organic compounds detected by GC/MS. Major part of organic halogen was suggested to be included in chlorinated organics formed by bleaching or sterilization.« less

  1. Metabolic Reactions among Organic Sulfur Compounds

    NASA Technical Reports Server (NTRS)

    Schulte, M.; Rogers, K.

    2005-01-01

    Sulfur is central to the metabolisms of many organisms that inhabit extreme environments. Numerous authors have addressed the energy available from a variety of inorganic sulfur redox pairs. Less attention has been paid, however, to the energy required or gained from metabolic reactions among organic sulfur compounds. Work in this area has focused on the oxidation of alkyl sulfide or disulfide to thiol and formaldehyde, e.g. (CH3)2S + H2O yields CH3SH + HCHO + H2, eventually resulting in the formation of CO2 and SO4(-2). It is also found that reactions among thiols and disulfides may help control redox disequilibria between the cytoplasm and the periplasm. Building on our earlier efforts for thiols, we have compiled and estimated thermodynamic properties for alkyl sulfides. We are investigating metabolic reactions among various sulfur compounds in a variety of extreme environments, ranging from sea floor hydrothermal systems to organic-rich sludge. Using thermodynamic data and the revised HKF equation of state, along with constraints imposed by the geochemical environments sulfur-metabolizing organisms inhabit, we are able to calculate the amount of energy available to these organisms.

  2. Molecular and Enantiomeric Analysis of Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Cooper, George

    2003-01-01

    Carbonaceous meteorites are relatively enriched in carbon. Much of this carbon is in the form of soluble organic compounds. The Murchison and Murray meteorites are the best-characterized carbonaceous meteorites with respect to organic chemistry. Their content of organic compounds has led to an initial understanding of early solar system organic chemistry as well as what compounds may have played a role in the origin of life (Cronin and Chang, 1993). Reported compounds include: amino acids, amides, carboxylic acids, sulfonic acids, and polyols. This talk will focus on the molecular and enantiomeric analysis of individual meteoritic compounds: polyol acids; and a newly identified class of meteorite compounds, keto acids, i.e., acetoacetic acid, levulinic acid, etc. Keto acids (including pyruvic) are critically important in all contemporary organisms. They are key intermediates in metabolism and processes such as the citric acid cycle. Using gas chromatography-mass spectrometry we identified individual meteoritic keto acids after derivatization to one or more of the following forms: isopropyl ester (ISP), trimethyIsiIy1 (TMS), tert-butyldimethylsilyl (BDMS). Ongoing analyses will determine if, in addition to certain amino acids from Murchison (Cronin and Pizzarello, 1997), other potentially important prebiotic compounds also contain enantiomeric excesses, i.e., excesses that could have contributed to the current homochirality of life.

  3. A Systematic Presentation of Organic Phosphorus and Sulfur Compounds.

    ERIC Educational Resources Information Center

    Hendrickson, James B.

    1985-01-01

    Because the names, interrelations, and oxidation levels of the organic compounds of phosphorus and sulfur tend to confuse students, a simple way to organize these compounds has been developed. The system consists of grouping them by oxidation state and extent of carbon substitution. (JN)

  4. Analysis of Organic Compounds in Mars Analog Samples

    NASA Technical Reports Server (NTRS)

    Mahaffy, P. R.; Brinckerhoff, W. B.; Buch, A.; Cabane, M.; Coll, P.; Demick, J.; Glavin, D. P.

    2004-01-01

    The detailed characterization of organic compounds that might be preserved in rocks, ices, or sedimentary layers on Mars would be a significant step toward resolving the question of the habitability and potential for life on that planet. The fact that the Viking gas chromatograph mass spectrometer (GCMS) did not detect organic compounds should not discourage further investigations since (a) an oxidizing environment in the near surface fines analyzed by Viking is likely to have destroyed many reduced carbon species; (b) there are classes of refractory or partially oxidized species such as carboxylic acids that would not have been detected by the Viking GCMS; and (c) the Viking landing sites are not representative of Mars overall. These factors motivate the development of advanced in situ analytical protocols to carry out a comprehensive survey of organic compounds in martian regolith, ices, and rocks. We combine pyrolysis GCMS for analysis of volatile species, chemical derivatization for transformation of less volatile organics, and laser desorption mass spectrometry (LDMS) for analysis of elements and more refractory, higher-mass organics. To evaluate this approach and enable a comparison with other measurement techniques we analyze organics in Mars simulant samples.

  5. Soil amino compound and carbohydrate contents influenced by organic amendments

    USDA-ARS?s Scientific Manuscript database

    Amino compounds (i. e. amino acids and sugars), and carbohydrates are labile organic components and contribute to the improvement of soil fertility and quality. Animal manure and other organic soil amendments are rich in both amino compounds and carbohydrates, hence organic soil amendments might af...

  6. Volatile organic compound emissions from silage systems

    USDA-ARS?s Scientific Manuscript database

    As a precursor to smog, emission of volatile organic compounds (VOCs) to the atmosphere is an environmental concern in some regions. The major source from farms is silage, with emissions coming from the silo face, mixing wagon, and feed bunk. The major compounds emitted are alcohols with other impor...

  7. Organic compounds in hydraulic fracturing fluids and wastewaters: A review.

    PubMed

    Luek, Jenna L; Gonsior, Michael

    2017-10-15

    High volume hydraulic fracturing (HVHF) of shale to stimulate the release of natural gas produces a large quantity of wastewater in the form of flowback fluids and produced water. These wastewaters are highly variable in their composition and contain a mixture of fracturing fluid additives, geogenic inorganic and organic substances, and transformation products. The qualitative and quantitative analyses of organic compounds identified in HVHF fluids, flowback fluids, and produced waters are reviewed here to communicate knowledge gaps that exist in the composition of HVHF wastewaters. In general, analyses of organic compounds have focused on those amenable to gas chromatography, focusing on volatile and semi-volatile oil and gas compounds. Studies of more polar and non-volatile organic compounds have been limited by a lack of knowledge of what compounds may be present as well as quantitative methods and standards available for analyzing these complex mixtures. Liquid chromatography paired with high-resolution mass spectrometry has been used to investigate a number of additives and will be a key tool to further research on transformation products that are increasingly solubilized through physical, chemical, and biological processes in situ and during environmental contamination events. Diverse treatments have been tested and applied to HVHF wastewaters but limited information has been published on the quantitative removal of individual organic compounds. This review focuses on recently published information on organic compounds identified in flowback fluids and produced waters from HVHF. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Composition and major sources of organic compounds in urban aerosols

    NASA Astrophysics Data System (ADS)

    Bi, Xinhui; Simoneit, Bernd R. T.; Sheng, Guoying; Ma, Shexia; Fu, Jiamo

    Total suspended particles (TSP), collected during June 2002 to July 2003 in Guangzhou, a typical economically developed city in South China, were analyzed for the organic compound compositions using gas chromatography-mass spectrometry (GC/MS). Over 140 organic compounds were detected in the aerosols and grouped into different classes including n-alkanes, hopanoids, polycyclic aromatic hydrocarbons, alkanols, fatty acids, dicarboxylic acids excluding oxalic acid, polyols/polyacids, lignin products, phytosterols, phthalates and water-soluble sugars. The total amounts of the identified organic compounds including unresolved complex mixture (UCM) ranged from 3112 ng/m 3 in spring to 5116 ng/m 3 in winter, comprising on seasonal average 2.8% of TSP. Primary organic compounds peaked in winter although there are no heating systems burning fuels in Guangzhou. The highest saccharide levels occurred in fall due to agricultural activities. This study demonstrated that utilization of fossil fuels, biomass burning, soil resuspension and plastic/refuse burning are the major contributors to the identified organic compounds in the urban atmosphere of South China.

  9. Plant-Associated Bacterial Degradation of Toxic Organic Compounds in Soil

    PubMed Central

    McGuinness, Martina; Dowling, David

    2009-01-01

    A number of toxic synthetic organic compounds can contaminate environmental soil through either local (e.g., industrial) or diffuse (e.g., agricultural) contamination. Increased levels of these toxic organic compounds in the environment have been associated with human health risks including cancer. Plant-associated bacteria, such as endophytic bacteria (non-pathogenic bacteria that occur naturally in plants) and rhizospheric bacteria (bacteria that live on and near the roots of plants), have been shown to contribute to biodegradation of toxic organic compounds in contaminated soil and could have potential for improving phytoremediation. Endophytic and rhizospheric bacterial degradation of toxic organic compounds (either naturally occurring or genetically enhanced) in contaminated soil in the environment could have positive implications for human health worldwide and is the subject of this review. PMID:19742157

  10. Thermodynamics of Aqueous Organic Sulfur Compounds: A Key to the Organic Geochemistry of Hydrothermal Systems?

    NASA Technical Reports Server (NTRS)

    Schulte, Mitchell; Rogers, Karyn L.; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    Hydrothermal environments are locations of varied geochemistry due to the disequilibrium between vent fluids and seawater. The disequilibrium geochemistry has been hypothesized to include reactions to synthesize organic compounds. Observations of the organic geochemistry of hydrothermal vent sites has received little attention. Experimental simulations of these environments, however, indicate that organic compounds may have difficulty forming in a purely aqueous environment. On the other hand, thiols. thioesters and disulfides have been implicated as reaction intermediates between CO or CO2 in experiments of carbon reduction in hydrothermal environments as well as in a variety of biological processes and other abiotic reactions (Wachtershauser, 1990, OLEB 20, 173; Heinen and Lauwers, 1996, OLEB 26, 13 1, Huber and Wachtershauser, 1997, Science 276, 245; Russell et al., 1998, in Thermophiles: The keys to molecular evolution and the origin of life?). The reduction of CO2 to thiols, for example, is observed using the FeS-H2S/FeS2 couple to provide the reducing power (see Schoonen et al., 1999, OLEB 29, 5). In addition, the enzyme involved in final stage of methanogenesis, coenzyme-M, is itself a thiol. Thus, organic sulfur compounds may hold the key to the organic chemistry leading to the origin of life at high temperatures. Understanding the biochemical processes of microorganisms that can live to temperatures at least as high as 113 C (Blochl et al., 1996, Extremophiles 1, 14) requires knowledge of the properties of the chemical reactions involved. In order to assess the role of aqueous organic sulfur compounds in hydrothermal organic geochemistry, we have been attempting to determine their thermodynamic properties. We have culled the literature to obtain the properties of organic sulfur compounds. We are able to calculate a number of essential properties, such as free energies of formation, from solubility data available in the literature together with standard

  11. 29 CFR 403.4 - Simplified annual reports for smaller labor organizations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., DEPARTMENT OF LABOR LABOR-MANAGEMENT STANDARDS LABOR ORGANIZATION ANNUAL FINANCIAL REPORTS § 403.4 Simplified... revocation of the privileges as provided in section 208 of the Act, to file the annual financial report... the privileges as provided in section 208 of the Act, to file the annual financial report called for...

  12. Selected trace metals and organic compounds and bioavailability of selected organic compounds in soils, Hackberry Flat, Tillman County, Oklahoma, 1994-95

    USGS Publications Warehouse

    Becker, M.F.

    1997-01-01

    In 1995 the Oklahoma Department of Wildlife Conservation acquired a drained wetland in southwest Oklahoma known as Hackberry Flat. Following restoration by Wildlife Conservation the wetland will be used by migratory birds and waterfowl. If naturally occurring trace metals and residual organic compounds from agriculture and industry were present, they may have posed a potential biohazard and were a concern for Wildlife Conservation. The U. S. Geological Survey, in cooperation with Wildlife Conservation and the Oklahoma Geological Survey, examined the soils of Hackberry Flat to determine trace metal concentrations, presence of selected organic compounds, and the bioavailability of selected organic compounds in the soils. The purpose of this report is to present the data that establish the baseline concentrations of selected trace metals and organic compounds in the soils of Hackberry Flat prior to wetland restoration. Sampling and analysis were performed using two approaches. One was to collect soil samples and analyze the composition with standard laboratory practices. The second exposed composite soils samples to organic-free water and a semipermeable membrane device that mimics an organism and then analyzed the device. Ten soil samples were collected in 1994 to be analyzed for trace metals, organochlorine pesticides, and polychlorinated biphenyls. Soil samples tested for bioavailability of selected organic compounds were collected in 1995. Most of the 182 soil samples collected were from the center of every 40-acre quarter-quarter section owned by the Wildlife Conservation. The samples were grouped by geographical area with a maximum of 16 sample sites per group. Concentrations of most selected trace metals measured from soils in Hackberry Flat are within the range of mean concentrations measured in cultivated soils within the United States. Organochlorine pesticides, polychlorinated biphenyls, and polyaromatic hydrocarbons were not found at concentrations above

  13. Racemization and the origin of optically active organic compounds in living organisms

    NASA Technical Reports Server (NTRS)

    Bada, J. L.; Miller, S. L.

    1987-01-01

    The organic compounds synthesized in prebiotic experiments are racemic mixtures. A number of proposals have been offered to explain how asymmetric organic compounds formed on the Earth before life arose, with the influence of chiral weak nuclear interactions being the most frequent proposal. This and other proposed asymmetric syntheses give only sight enantiomeric excess and any slight excess will be degraded by racemization. This applies particularly to amino acids where half-lives of 10(5)-10(6) years are to be expected at temperatures characteristic of the Earth's surface. Since the generation of chiral molecules could not have been a significant process under geological conditions, the origins of this asymmetry must have occurred at the time of the origin of life or shortly thereafter. It is possible that the compounds in the first living organisms were prochiral rather than chiral; this is unlikely for amino acids, but it is possible for the monomers of RNA-like molecules.

  14. Shock Modifications of Organic Compounds in Carbonaceous Chondrite Parent Bodies

    NASA Technical Reports Server (NTRS)

    Cooper, George W.

    1998-01-01

    Impacts among asteroidal objects would have altered or destroyed pre-existing organic matter in both targets and projectiles to a greater or lesser degree depending upon impact velocities. To begin filling a knowledge gap on the shock metamorphism of organic compounds, we are studying the effects of shock impacts on selected classes of organic compounds utilizing laboratory shock facilities. Our approach is to subject mixtures of organic compounds, embedded in the matrix of the Murchison meteorite, to simulated hypervelocity impacts by firing them into targets at various pressures. The mixtures are then analyzed to determine the amount of each compound that survives as well as to determine if new compounds are being synthesized. The initial compounds added to the matrix (with the exception of thiosulfate). The sulfonic acids were chosen in part because they are relatively abundant in Murchison, relatively stable, and because they and the phosphonic acids are the first well-characterized homologous series of organic sulfur and phosphorus compounds identified in an extraterrestrial material. Experimental procedures were more fully described in the original proposal. A 20 mm gun, with its barrel extending into a vacuum chamber (10(exp -2) torr), was used to launch the projectile containing the sample at approx. 1.6 km/sec (3,600 mi/hr) into the target material. Maximum pressure of impact depend on target/projectile materials. The target was sufficiently thin to assure minimum pressure decay over the total sample thickness.

  15. Biogenic volatile organic compounds in the Earth system.

    PubMed

    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.

  16. Enantiomeric and Isotopic Analysis of Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Cooper, George

    2004-01-01

    Carbonaceous meteorites are relatively enriched in soluble organic compounds. The Murchison and Murray meteorites contain numerous compounds of interest in the study of early solar system organic chemistry and organic compounds of potential importance for the origin of life. These include: amino acids, amides, carboxylic acids, and polyols. This talk will focus on the enantiomeric and isotopic analysis of individual meteoritic compounds - primarily polyol acids. The analyses will determine if, in addition to certain amino acids from Murchison, another potentially important class of prebiotic compounds also contains enantiomeric excesses, i.e., excesses that could have contributed to the current homochirality of life. Preliminary enantiomeric and isotopic (C- 13) measurements of Murchison glyceric acid show that it is indeed extraterrestrial. C-13 and D isotope analysis of meteoritic sugar alcohols (glycerol, threitol, ribitol, etc.) has shown that they are also indigenous to the meteorite.

  17. VOLATILE ORGANIC COMPOUNDS AS EXPOSURE BIOMARKERS

    EPA Science Inventory

    Alveolar breath sampling and analysis can be extremely useful in exposure assessment studies involving volatile organic compounds (VOCs). Over recent years scientists from the US Environmental Protection Agency's National Exposure Research Laboratory have developed and refined...

  18. Tritium labeling of organic compounds deposited on porous structures

    DOEpatents

    Ehrenkaufer, Richard L. E.; Wolf, Alfred P.; Hembree, Wylie C.

    1979-01-01

    An improved process for labeling organic compounds with tritium is carried out by depositing the selected compound on the extensive surface of a porous structure such as a membrane filter and exposing the membrane containing the compound to tritium gas activated by the microwave discharge technique. The labeled compound is then recovered from the porous structure.

  19. Volatile organic compound and semivolatile organic compound outgassing rates for ethylene propylene diene monomer and fluoropolymer seals

    NASA Astrophysics Data System (ADS)

    Pecault, Isabelle Tovena

    2017-11-01

    High-power laser facilities, such as Laser MegaJoule, are currently being operated for inertial confinement fusion experiments. Emission of volatile organic compounds (VOC) and moreover semivolatile organic compounds (SVOCs) from seals in laser environment is of tremendous importance for the optics lifetime and laser performance. That is why all the seals were screening in the same conditions: 48 h at 30°C and three successive cycle of 1.5 h at 50°C. This paper focuses on the qualification test performed on three seals: two ethylene propylene diene monomer (EPDM) and one fluoropolymer (FPM). It is shown that the molded and the extruded EPDM do not outgas the same amount neither the same molecules whereas EPDM and FPM outgas nearly the same level of phthalates.

  20. VOLATILE ORGANIC COMPOUNDS MEASURED IN DEARS PASSIVE SAMPLERS

    EPA Science Inventory

    A suite of 27 volatile organic compounds (VOCs) were monitored in personal exposures, indoors and outdoors of participant's residences, and at a central community site during the DEARS summer 2004 monitoring season. The list of VOCs focused on compounds typically associated with ...

  1. Photocatalytic oxidation of organic compounds on Mars

    NASA Technical Reports Server (NTRS)

    Chun, S. F. S.; Pang, K. D.; Cutts, J. A.; Ajello, J. M.

    1978-01-01

    Ultraviolet-stimulated catalytic oxidation is proposed as a mechanism for the destruction of organic compounds on Mars. The process involves the presence of gaseous oxygen, UV radiation, and a catalyst (titanium dioxide), and all three of these have been found to be present in the Martian environment. Therefore it seems plausible that UV-stimulated oxidation of organics is responsible for degrading organic molecules into inorganic end products.

  2. Proceedings of the twentieth annual meeting of the society for organic petrology

    USGS Publications Warehouse

    Bragg, Linda J.; Lentz, Erika E.; Warwick, Peter D.; Finkelman, Robert B.; Trippi, Michael H.; Karlsen, Alex W.

    2004-01-01

    The Society for Organic Petrology (TSOP; pronounced "Tee'-sop") was established in 1984 to consolidate and foster the organizational activities of scientists and engineers involved with coal petrology, kerogen petrology, organic geochemistry, and related disciplines. The following report, "Proceedings of the Twentieth Annual Meeting of The Society for Organic Petrology" (ISSN 1060-7250), features technical talks, poster presentations, business meetings, short courses, and field trips from the Fall 2003 annual meeting held in Washington, D.C.

  3. INDOOR AIR QUALITY DATA BASE FOR ORGANIC COMPOUNDS

    EPA Science Inventory

    The report gives results of the compilation of a data base for concentrations of organic compounds measured indoors. ased on a review of the literature from 1979 through 1990, the data base contains information on over 220 compounds ranging in molecular weight from 30 to 446. he ...

  4. Determination of fluorine in organic compounds: Microcombustion method

    USGS Publications Warehouse

    Clark, H.S.

    1951-01-01

    A reliable and widely applicable means of determining fluorine in organic compounds has long been needed. Increased interest in this field of research in recent years has intensified the need. Fluorine in organic combinations may be determined by combustion at 900?? C. in a quartz tube with a platinum catalyst, followed by an acid-base titration of the combustion products. Certain necessary precautions and known limitations are discussed in some detail. Milligram samples suffice, and the accuracy of the method is about that usually associated with the other halogen determinations. Use of this method has facilitated the work upon organic fluorine compounds in this laboratory and it should prove to be equally valuable to others.

  5. Volatile organic compounds in Gulf of Mexico sediments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McDonald, T.J.

    1988-01-01

    Volatile organic compounds (VOC), concentrations and compositions were documented for estuarine, coastal, shelf, slope, and deep water sediments from the Gulf of Mexico. VOC were measured (detection limit >0.01 ppb) using a closed-loop stripping apparatus with gas chromatography (GC) and flame ionization, flame photometric, and mass spectrometric detectors. The five primary sources of Gulf of Mexico sediment VOC are: (1) planktonic and benthic fauna and flora; (2) terrestrial material from riverine and atmospheric deposition; (3) anthropogenic inputs: (4) upward migration of hydrocarbons; and (5) transport by bottom currents or slumping. Detected organo-sulfur compounds include alkylated sulfides, thiophene, alkylated thiophenes, andmore » benzothiophenes. Benzothiophenes are petroleum related. Low molecular weight organo-sulfur compounds result from the biological oxidation of organic matter. A lack of organosulfur compounds in the reducing environment of the Orca Basin may result from a lack of free sulfides which are necessary for their production.« less

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

    NASA Astrophysics Data System (ADS)

    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.

  7. Organic compound composition in soil and sediments collected in Jackson, Mississippi.

    PubMed

    Gołębiowski, Marek; Stepnowski, Piotr; Hemmingway, Tometrick; Leszczyńska, Danuta

    2016-01-01

    The aim of our study was to identify organic pollutants found in soil and sediment samples collected within the Jackson, MS metropolitan area. The chemical characterization of the organic compound fractions in soil and sediment samples was carried out by separating the organic fraction using column chromatography (CC) and quantitatively analyzing the polycyclic aromatic hydrocarbons (PAHs), n-alkanes and other organic compounds using gas chromatography-electron impact mass spectrometry (GC-MS). Fifty-six compounds were identified and quantified in the soil samples and 33 compounds were identified and quantified in the sediment samples. The PAHs, n-alkanes and other organic compound profiles in the soil and sediment samples were compared. The percentage contents of the organic compounds in the soil samples were very diverse (from traces to 12.44 ± 1.47%). The compounds present in the highest concentrations were n-alkanes: n-C31 (12.44 ± 1.47%), n-C29 (11.64 ± 1.21%), and n-C33 (8.95 ± 1.08%). The components occurring in smaller quantities (from 1% to 5%) were 2 PAHs (fluoranthene 1.28 ± 0.25%, pyrene 1.16 ± 0.20%), 10 n-alkanes from n-C21 (1.25 ± 0.29%) to n-C32 (2.67 ± 0.52%) and 11 other compounds (e.g., 2-pentanol, 4-methyl (3.33 ± 0.44%), benzyl butyl phthalate (4.25 ± 0.59%), benzenedicarboxylic acid (1.14 ± 0.08%), ethane, 1,1-diethoxy (3.15 ± 0.41) and hexadecanoic acid (2.52 ± 0.34). The soil samples also contained 30 compounds present in concentrations <1% (e.g., anthracene (0.13 ± 0.04%), n-C20 (0.84 ± 0.21%) and acetic acid (0.12 ± 0.04%). The compounds present in the highest concentrations in the sediment samples were PAHs: pyrene (7.73 ± 1.15%) and fluoranthene (6.23 ± 1.07%) and n-alkanes: n-C31 (6.74 ± 1.21%), n-C29 (6.65 ± 0.98%) and n-C27 (6.13 ± 1.09%). The remaining organic compounds were present in smaller quantities (< 5%).

  8. Organic photosensitive devices using subphthalocyanine compounds

    DOEpatents

    Rand, Barry [Princeton, NJ; Forrest, Stephen R [Ann Arbor, MI; Mutolo, Kristin L [Hollywood, CA; Mayo, Elizabeth [Alhambra, CA; Thompson, Mark E [Anaheim Hills, CA

    2011-07-05

    An organic photosensitive optoelectronic device, having a donor-acceptor heterojunction of a donor-like material and an acceptor-like material and methods of making such devices is provided. At least one of the donor-like material and the acceptor-like material includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound; and/or the device optionally has at least one of a blocking layer or a charge transport layer, where the blocking layer and/or the charge transport layer includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound.

  9. Enhanced transport of low-polarity organic compounds through soil by cyclodextrin

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brusseau, M.L.; Wang, X.; Hu, Q.

    1994-05-01

    The removal of low-polarity organic compounds from soils and aquifers by water flushing is often constrained by sorption interactions. There is great interest in developing systems that can enhance the transport of organic compounds through porous media, thus facilitating remediation. We investigated the potential of hydroxypropyl-[beta]-cyclodextrin (HPCD), a microbially produced compound, to reduce the sorption and to enhance the transport of several low-polarity organic compounds. The results show that cyclodextrin does not interact with the two porous media used in the study. As a result, there is no retardation of cyclodextrin during transport. The retardation of compounds such as anthracene,more » pyrene, and trichlorobiphenyl was significantly (orders of magnitude) reduced in the presence of cyclodextrin. The enhancement effect of the cyclodextrin was predictable with a simple equation based on three-phase partitioning. The nonreactive nature of cyclodextrin combined with its large affinity for low-polarity organic compounds makes cyclodextrin a possible candidate for use in in-situ remediation efforts. 22 refs., 6 figs., 3 tabs.« less

  10. Historic records of organic compounds from a high Alpine glacier: influences of biomass burning, anthropogenic emissions, and dust transport

    NASA Astrophysics Data System (ADS)

    Müller-Tautges, C.; Eichler, A.; Schwikowski, M.; Pezzatti, G. B.; Conedera, M.; Hoffmann, T.

    2016-01-01

    Historic records of α-dicarbonyls (glyoxal, methylglyoxal), carboxylic acids (C6-C12 dicarboxylic acids, pinic acid, p-hydroxybenzoic acid, phthalic acid, 4-methylphthalic acid), and ions (oxalate, formate, calcium) were determined with annual resolution in an ice core from Grenzgletscher in the southern Swiss Alps, covering the time period from 1942 to 1993. Chemical analysis of the organic compounds was conducted using ultra-high-performance liquid chromatography (UHPLC) coupled to electrospray ionization high-resolution mass spectrometry (ESI-HRMS) for dicarbonyls and long-chain carboxylic acids and ion chromatography for short-chain carboxylates. Long-term records of the carboxylic acids and dicarbonyls, as well as their source apportionment, are reported for western Europe. This is the first study comprising long-term trends of dicarbonyls and long-chain dicarboxylic acids (C6-C12) in Alpine precipitation. Source assignment of the organic species present in the ice core was performed using principal component analysis. Our results suggest biomass burning, anthropogenic emissions, and transport of mineral dust to be the main parameters influencing the concentration of organic compounds. Ice core records of several highly correlated compounds (e.g., p-hydroxybenzoic acid, pinic acid, pimelic, and suberic acids) can be related to the forest fire history in southern Switzerland. P-hydroxybenzoic acid was found to be the best organic fire tracer in the study area, revealing the highest correlation with the burned area from fires. Historical records of methylglyoxal, phthalic acid, and dicarboxylic acids adipic acid, sebacic acid, and dodecanedioic acid are comparable with that of anthropogenic emissions of volatile organic compounds (VOCs). The small organic acids, oxalic acid and formic acid, are both highly correlated with calcium, suggesting their records to be affected by changing mineral dust transport to the drilling site.

  11. Seeking organic compounds on Mars : in situ analysis of organic compounds by Gas Chromatography-Mass Spectrometry on MOMA experiment

    NASA Astrophysics Data System (ADS)

    Buch, A.; Freissinet, C.; Sternberg, R.; Pinnick, V.; Szopa, C.; Coll, P. J.; Rodier, C.; Garnier, C.; Steininger, H.; Moma Team

    2010-12-01

    The search for signs of past or present life is one of the primary goals of future Mars exploratory missions. The Mars Organic Molecule Analyzer (MOMA) experiment of the ExoMars mission (set to launch 2016-2018) is a joint venture by the European Space Agency and NASA to develop a sensitive detector for organics on Mars. MOMA will be one of the main analytical instruments aboard the ExoMars Rover aimed at characterizing possible “signs-of-life molecules” in the Martian environment such as amino acids, carboxylic acids, nucleobases or polycyclic aromatic hydrocarbons (PAHs). With the aim to separate and detect organic compounds from Martian soil, the French MOMA team has built a gas chromatograph able to work in standalone mode by using a TCD detector. The gas chromatograph can also be coupled with an ion trap mass spectrometer developed by the US MOMA team. Moreover, a GC-MS compatible sample processing system (SPS) allowing the extraction and the chemical transformation of the organic compounds from the soil, that fits within space flight conditions, has also been developed. The sample processing is performed in an oven, dedicated to the MOMA experiment containing the solid sample (50-100mg). The internal temperature of oven can be ranged from 20 to 1000 °C which allows for pyrolysis, thermochemolysis or derivatization. The organic extraction step is achieved by using thermodesorption in the range of 100 to 300°C for 0.5 to 5 min. Then, the chemical derivatization and/or thermochemolysis of the extracted compounds is performed directly on the soil with a mixture of MTBSTFA-DMF, TMAH or DMF-DMA solution when enantiomeric separation is required. By decreasing the polarity of the target molecules, this step allows for their volatilization at a temperature below 250°C without any chemical degradation. Once derivatized, the volatile target molecules are trapped in a cold chemical trap and promptly desorbed into the gas chromatograph coupled to the mass

  12. INTERACTIONS BETWEEN ORGANIC COMPOUNDS AND CYCLODEXTRIN-CLAY SYSTEMS

    EPA Science Inventory

    Computational and experimental techniques are combined in order to better understand interactions involving organic compounds and cyclodextrin (CD)-clay systems. CD-clay systems may have great potential in the containment of organic contaminants in the environment. This study w...

  13. Phosphorus-containing nucleophiles in reactions with polyfluorinated organic compounds

    NASA Astrophysics Data System (ADS)

    Furin, Georgii G.

    1993-03-01

    The review presents a compilation of new expelimental data on the reactions of phosphorus-containing nucleophiles [triphenylphosphine, trialkylphosphines, trialkyl phosphites, phosphorus tris(diethylamide), etc.] with perfluorinated olefins and aromatic and heterocyclic compounds, leading to substances both with and without a phosphorus atom. It is shown that the interaction of phosphorus tris(diethylamide) and trialkylphosphines with organic polyfluoro-compounds and perfluoroolefins leads to the formation of phosphoranes, the decomposition of which is accompanied by the generation of aryl and alkenyl anions. The reactions of these anions with C-electrophiles and compounds containing mobile halogen atoms are examined. In addition, the pathways in the Arbuzov reaction involving a series of unsaturated perfluorinated compounds are analysed. Possible applications of these reactions in organic synthesis are demonstrated. The bibliography includes 120 references.

  14. ACUTE TOXICITY OF SELECTED ORGANIC COMPOUNDS TO FATHEAD MINNOWS

    EPA Science Inventory

    Static nonrenewal laboratory bioassays were conducted with 26 organic compounds commonly used by industry. The selected compounds represented the five following chemical classes: acids, alcohols, hydrocarbons, ketones and aldehydes, and phenols. Juvenile fathead minnows (Pimephal...

  15. Abiotic synthesis of organic compounds from carbon disulfide under hydrothermal conditions.

    PubMed

    Rushdi, Ahmed I; Simoneit, Bernd R T

    2005-12-01

    Abiotic formation of organic compounds under hydrothermal conditions is of interest to bio, geo-, and cosmochemists. Oceanic sulfur-rich hydrothermal systems have been proposed as settings for the abiotic synthesis of organic compounds. Carbon disulfide is a common component of magmatic and hot spring gases, and is present in marine and terrestrial hydrothermal systems. Thus, its reactivity should be considered as another carbon source in addition to carbon dioxide in reductive aqueous thermosynthesis. We have examined the formation of organic compounds in aqueous solutions of carbon disulfide and oxalic acid at 175 degrees C for 5 and 72 h. The synthesis products from carbon disulfide in acidic aqueous solutions yielded a series of organic sulfur compounds. The major compounds after 5 h of reaction included dimethyl polysulfides (54.5%), methyl perthioacetate (27.6%), dimethyl trithiocarbonate (6.8%), trithianes (2.7%), hexathiepane (1.4%), trithiolanes (0.8%), and trithiacycloheptanes (0.3%). The main compounds after 72 h of reaction consisted of trithiacycloheptanes (39.4%), pentathiepane (11.6%), tetrathiocyclooctanes (11.5%), trithiolanes (10.6%), tetrathianes (4.4%), trithianes (1.2%), dimethyl trisulfide (1.1%), and numerous minor compounds. It is concluded that the abiotic formation of aliphatic straight-chain and cyclic polysulfides is possible under hydrothermal conditions and warrants further studies.

  16. Screening for Anti-Cancer Compounds in Marine Organisms in Oman

    PubMed Central

    Dobretsov, Sergey; Tamimi, Yahya; Al-Kindi, Mohamed A.; Burney, Ikram

    2016-01-01

    Objectives: Marine organisms are a rich source of bioactive molecules with potential applications in medicine, biotechnology and industry; however, few bioactive compounds have been isolated from organisms inhabiting the Arabian Gulf and the Gulf of Oman. This study aimed to isolate and screen the anti-cancer activity of compounds and extracts from 40 natural products of marine organisms collected from the Gulf of Oman. Methods: This study was carried out between January 2012 and December 2014 at the Sultan Qaboos University, Muscat, Oman. Fungi, bacteria, sponges, algae, soft corals, tunicates, bryozoans, mangrove tree samples and sea cucumbers were collected from seawater at Marina Bandar Al-Rowdha and Bandar Al-Khayran in Oman. Bacteria and fungi were isolated using a marine broth and organisms were extracted with methanol and ethyl acetate. Compounds were identified from spectroscopic data. The anti-cancer activity of the compounds and extracts was tested in a Michigan Cancer Foundation (MCF)-7 cell line breast adenocarcinoma model. Results: Eight pure compounds and 32 extracts were investigated. Of these, 22.5% showed strong or medium anti-cancer activity, with malformin A, kuanoniamine D, hymenialdisine and gallic acid showing the greatest activity, as well as the soft coral Sarcophyton sp. extract. Treatment of MCF-7 cells at different concentrations of Sarcophyton sp. extracts indicated the induction of concentration-dependent cell death. Ultrastructural analysis highlighted the presence of nuclear fragmentation, membrane protrusion, blebbing and chromatic segregation at the nuclear membrane, which are typical characteristics of cell death by apoptosis induction. Conclusion: Some Omani marine organisms showed high anti-cancer potential. The efficacy, specificity and molecular mechanisms of anti-cancer compounds from Omani marine organisms on various cancer models should be investigated in future in vitro and in vivo studies. PMID:27226907

  17. Volatile Organic Compound Analysis in Istanbul

    NASA Astrophysics Data System (ADS)

    Ćapraz, Ö.; Deniz, A.; Öztürk, A.; Incecik, S.; Toros, H.; Coşkun, M.

    2012-04-01

    Volatile Organic Compound Analysis in Istanbul Ö. Çapraz1, A. Deniz1,3, A. Ozturk2, S. Incecik1, H. Toros1 and, M. Coskun1 (1) Istanbul Technical University, Faculty of Aeronautics and Astronautics, Department of Meteorology, 34469, Maslak, Istanbul, Turkey. (2) Istanbul Technical University, Faculty of Chemical and Metallurgical, Chemical Engineering, 34469, Maslak, Istanbul, Turkey. (3) Marmara Clean Air Center, Ministry of Environment and Urbanization, Nişantaşı, 34365, İstanbul, Turkey. One of the major problems of megacities is air pollution. Therefore, investigations of air quality are increasing and supported by many institutions in recent years. Air pollution in Istanbul contains many components that originate from a wide range of industrial, heating, motor vehicle, and natural emissions sources. VOC, originating mainly from automobile exhaust, secondhand smoke and building materials, are one of these compounds containing some thousands of chemicals. In spite of the risks to human health, relatively little is known about the levels of VOC in Istanbul. In this study, ambient air quality measurements of 32 VOCs including hydrocarbons, halogenated hydrocarbons and carbonyls were conducted in Kağıthane (Golden Horn) region in Istanbul during the winter season of 2011 in order to develop the necessary scientific framework for the subsequent developments. Kağıthane creek valley is the source part of the Golden Horn and one of the most polluted locations in Istanbul due to its topographical form and pollutant sources in the region. In this valley, horizontal and vertical atmospheric motions are very weak. The target compounds most commonly found were benzene, toluene, xylene and ethyl benzene. Concentrations of total hydrocarbons ranged between 1.0 and 10.0 parts per billion, by volume (ppbv). Ambient air levels of halogenated hydrocarbons appeared to exhibit unique spatial variations and no single factor seemed to explain trends for this group of

  18. The Survival of Meteorite Organic Compounds with Increasing Impact Pressure

    NASA Technical Reports Server (NTRS)

    Cooper, George; Horz, Friedrich; Oleary, Alanna; Chang, Sherwood; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    The majority of carbonaceous meteorites studied today are thought to originate in the asteroid belt. Impacts among asteroidal objects generate heat and pressure that may have altered or destroyed pre-existing organic matter in both targets and projectiles to a greater or lesser degree depending upon impact velocities. Very little is known about the shock related chemical evolution of organic matter relevant to this stage of the cosmic history of biogenic elements and compounds. The present work continues our study of the effects of shock impacts on selected classes of organic compounds utilizing laboratory shock facilities. Our approach was to subject mixtures of organic compounds, embedded in a matrix of the Murchison meteorite, to a simulated hypervelocity impact. The molecular compositions of products were then analyzed to determine the degree of survival of the original compounds. Insofar as results associated with velocities < 8 km/sec may be relevant to impacts on planetary surfaces (e.g., oblique impacts, impacts on small outer planet satellites) or grain-grain collisions in the interstellar medium, then our experiments will be applicable to these environments as well.

  19. BIOCONCENTRATION FACTORS FOR VOLATILE ORGANIC COMPOUNDS IN VEGETATION

    EPA Science Inventory

    Samples of air and leaves were taken at the University of Nevada-Las Vegas campus and analyzed for volatile organic compounds using vacuum distillation coupled with gas chromatography/mass spectrometry. The data were used to estimate the bioconcentration of volatile organic compo...

  20. Detection of organic compounds with whole-cell bioluminescent bioassays.

    PubMed

    Xu, Tingting; Close, Dan; Smartt, Abby; Ripp, Steven; Sayler, Gary

    2014-01-01

    Natural and manmade organic chemicals are widely deposited across a diverse range of ecosystems including air, surface water, groundwater, wastewater, soil, sediment, and marine environments. Some organic compounds, despite their industrial values, are toxic to living organisms and pose significant health risks to humans and wildlife. Detection and monitoring of these organic pollutants in environmental matrices therefore is of great interest and need for remediation and health risk assessment. Although these detections have traditionally been performed using analytical chemical approaches that offer highly sensitive and specific identification of target compounds, these methods require specialized equipment and trained operators, and fail to describe potential bioavailable effects on living organisms. Alternatively, the integration of bioluminescent systems into whole-cell bioreporters presents a new capacity for organic compound detection. These bioreporters are constructed by incorporating reporter genes into catabolic or signaling pathways that are present within living cells and emit a bioluminescent signal that can be detected upon exposure to target chemicals. Although relatively less specific compared to analytical methods, bioluminescent bioassays are more cost-effective, more rapid, can be scaled to higher throughput, and can be designed to report not only the presence but also the bioavailability of target substances. This chapter reviews available bacterial and eukaryotic whole-cell bioreporters for sensing organic pollutants and their applications in a variety of sample matrices.

  1. Detection of Organic Compounds with Whole-Cell Bioluminescent Bioassays

    PubMed Central

    Xu, Tingting; Close, Dan; Smartt, Abby; Ripp, Steven

    2015-01-01

    Natural and manmade organic chemicals are widely deposited across a diverse range of ecosystems including air, surface water, groundwater, wastewater, soil, sediment, and marine environments. Some organic compounds, despite their industrial values, are toxic to living organisms and pose significant health risks to humans and wildlife. Detection and monitoring of these organic pollutants in environmental matrices therefore is of great interest and need for remediation and health risk assessment. Although these detections have traditionally been performed using analytical chemical approaches that offer highly sensitive and specific identification of target compounds, these methods require specialized equipment and trained operators, and fail to describe potential bioavailable effects on living organisms. Alternatively, the integration of bioluminescent systems into whole-cell bioreporters presents a new capacity for organic compound detection. These bioreporters are constructed by incorporating reporter genes into catabolic or signaling pathways that are present within living cells and emit a bioluminescent signal that can be detected upon exposure to target chemicals. Although relatively less specific compared to analytical methods, bioluminescent bioassays are more cost-effective, more rapid, can be scaled to higher throughput, and can be designed to report not only the presence but also the bioavailability of target substances. This chapter reviews available bacterial and eukaryotic whole-cell bioreporters for sensing organic pollutants and their applications in a variety of sample matrices. PMID:25084996

  2. 75 FR 75904 - Rescission of Form T-1, Trust Annual Report; Requiring Subsidiary Organization Reporting on the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-07

    ... DEPARTMENT OF LABOR Office of Labor-Management Standards 29 CFR Part 403 RIN 1215--AB75; 1245--AA02 Rescission of Form T-1, Trust Annual Report; Requiring Subsidiary Organization Reporting on the Form LM-2, Labor Organization Annual Report; Modifying Subsidiary Organization Reporting on the Form LM-3, Labor Organization Annual Report; LMRDA...

  3. Volatile and semivolatile organic compounds in laboratory peat fire emissions

    NASA Astrophysics Data System (ADS)

    George, Ingrid J.; Black, Robert R.; Geron, Chris D.; Aurell, Johanna; Hays, Michael D.; Preston, William T.; Gullett, Brian K.

    2016-05-01

    In this study, volatile and semi-volatile organic compound (VOCs and SVOCs) mass emission factors were determined from laboratory peat fire experiments. The peat samples originated from two National Wildlife Refuges on the coastal plain of North Carolina, U.S.A. Gas- and particle-phase organic compounds were quantified by gas chromatography-mass spectrometry and by high pressure liquid chromatography. Hazardous air pollutants (HAPs) accounted for a large fraction (∼60%) of the speciated VOC emissions from peat burning, including large contributions of acetaldehyde, formaldehyde, benzene, toluene, and chloromethane. In the fine particle mass (PM2.5), the following organic compound classes were dominant: organic acids, levoglucosan, n-alkanes, and n-alkenes. Emission factors for the organic acids in PM2.5 including n-alkanoic acids, n-alkenoic acids, n-alkanedioic acids, and aromatic acids were reported for the first time for peat burning, representing the largest fraction of organic carbon (OC) mass (11-12%) of all speciated compound classes measured in this work. Levoglucosan contributed to 2-3% of the OC mass, while methoxyphenols represented 0.2-0.3% of the OC mass on a carbon mass basis. Retene was the most abundant particulate phase polycyclic aromatic hydrocarbon (PAH). Total HAP VOC and particulate PAH emissions from a 2008 peat wildfire in North Carolina were estimated, suggesting that peat fires can contribute a large fraction of state-wide HAP emissions.

  4. Instrument for Analysis of Organic Compounds on Other Planets

    NASA Technical Reports Server (NTRS)

    Daulton, Riley M.; Hintze, Paul E.

    2016-01-01

    The goal of this project is to develop the Instrument for Solvent Extraction and Analysis of Extraterrestrial Bodies using In Situ Resources (ISEE). Specifically, ISEE will extract and characterize organic compounds from regolith which is found on the surface of other planets or asteroids. The techniques this instrument will use are supercritical fluid extraction (SFE) and supercritical fluid chromatography (SFC). ISEE aligns with NASA's goal to expand the frontiers of knowledge, capability, and opportunities in space in addition to supporting NASA's aim to search for life elsewhere by characterizing organic compounds. The outcome of this project will be conceptual designs of 2 components of the ISEE instrument as well as the completion of proof-of-concept extraction experiments to demonstrate the capabilities of SFE. The first conceptual design is a pressure vessel to be used for the extraction of the organic compounds from the regolith. This includes a comparison of different materials, geometry's, and a proposition of how to insert the regolith into the vessel. The second conceptual design identifies commercially available fluid pumps based on the requirements needed to generate supercritical CO2. The proof-of-concept extraction results show the percent mass lost during standard solvent extractions of regolith with organic compounds. This data will be compared to SFE results to demonstrate the capabilities of ISEE's approach.

  5. Precipitate hydrolysis process for the removal of organic compounds from nuclear waste slurries

    DOEpatents

    Doherty, Joseph P.; Marek, James C.

    1989-01-01

    A process for removing organic compounds from a nuclear waste slurry comprising reacting a mixture of radioactive waste precipitate slurry and an acid in the presence of a catalytically effective amount of a copper (II) catalyst whereby the organic compounds in the precipitate slurry are hydrolyzed to form volatile organic compounds which are separated from the reacting mixture. The resulting waste slurry, containing less than 10 percent of the orginal organic compounds, is subsequently blended with high level radioactive sludge and transferred to a virtrification facility for processing into borosilicate glass for long-term storage.

  6. Transformations of Model Organic Compounds on Snow Grains at Summit, Greenland

    NASA Astrophysics Data System (ADS)

    Galbavy, E. S.; Ram, K.; Anastasio, C.

    2005-12-01

    Photochemical reactions in snowpacks produce a number of chemicals species that can significantly impact the overlying atmosphere and transform many organic pollutants. During this past summer's field season at Summit we examined the kinetics for the disappearance of a suite of model organic compounds in surface snowpack. Our compounds (2-nitrobenzaldehyde, sodium benzoate, syringol, 4-chlorophenol, 2-oxo-butanoic acid, and phenanthrene) were chosen because they represent markers from several different emission sources and because they have a range of expected fates, i.e., their lifetimes will be determined by different processes. These processes include direct photolysis and reactions with oxidants such as hydroxyl radical (OH) and singlet molecular oxygen (1O2*) In addition to measuring the rates of loss of the model organics, we also measured concentrations of OH and 1O2* in the snow samples, as well as rates of direct photolysis of the organics in frozen, purified water. Our goal was to compare the measured lifetimes of the organic compounds with calculated lifetimes based on reactions with OH and 1O2* and direct photolysis. While certain compounds behaved as expected, others decayed more slowly, or more rapidly, than expected, indicating that other, unidentified, snow grain reactions and/or mechanisms are significant. The rates of organic compound loss, the potential reasons for the observed differences, and the implications for lifetimes of trace organic pollutants in polar regions will be discussed.

  7. HS-SPME analysis of volatile organic compounds of coniferous needle litter

    NASA Astrophysics Data System (ADS)

    Isidorov, V. A.; Vinogorova, V. T.; Rafałowski, K.

    The composition of volatile emission of Scots pine ( Pinus sylvestris) and spruce ( Picea exelsa) litter was studied by gas chromatography-mass spectrometry (GC-MS) and samples were collected by solid-phase microextraction (SPME) method. The list of identified compounds includes over 60 organic substances of different classes. It was established that volatile emission contain not only components of essential oils of pine and spruce needles but also a large number of organic compounds which are probably secondary metabolites of litter-decomposing fungi. They include lower carbonyl compounds and alcohols as well as products of terpene dehydration and oxidation. These data show that the processes of litter decomposition are an important source of reactive organic compounds under canopy of coniferous forests.

  8. Delivery of complex organic compounds from evolved stars to the solar system.

    PubMed

    Kwok, Sun

    2011-12-01

    Stars in the late stages of evolution are able to synthesize complex organic compounds with aromatic and aliphatic structures over very short time scales. These compounds are ejected into the interstellar medium and distributed throughout the Galaxy. The structures of these compounds are similar to the insoluble organic matter found in meteorites. In this paper, we discuss to what extent stellar organics has enriched the primordial Solar System and possibly the early Earth.

  9. On the enrichment of hydrophobic organic compounds in fog droplets

    NASA Astrophysics Data System (ADS)

    Valsaraj, K. T.; Thoma, G. J.; Reible, D. D.; Thibodeaux, L. J.

    The unusual degree of enrichment of hydrophobic organics in fogwater droplets reported by several investigators can be interpreted as a result of (a) the effects of temperature correction on the reported enrichment factors, (b) the effects of colloidal organic matter (both filterable and non-filterable) in fog water and (c) the effects of the large air-water interfacial adsorption of neutral hydrophobic organics on the tiny fog droplets. The enrichment factor was directly correlated to the hydrophobicity (or the activity coefficient in water) of the compounds, as indicated by their octanol-water partition constants. Compounds with large octanol-water partition coefficients (high activity coefficients in water) showed the largest enrichment. Available experimental data on the adsorption of hydrophobic compounds at the air-water interface and on colloidal organic carbon were used to show that the large specific air-water interfacial areas of fog droplets contribute significantly to the enrichment factor.

  10. Organic compounds leached from fast pyrolysis mallee leaf and bark biochars.

    PubMed

    Lievens, Caroline; Mourant, Daniel; Gunawan, Richard; Hu, Xun; Wang, Yi

    2015-11-01

    Characterization of organic compounds leached from biochars is essential in assessing the possible toxicity of the biochar to the soils' biota. In this study the nature of the leached organic compounds from Mallee biochars, produced from pyrolysis of Mallee leaf and bark in a fluidised-bed pyrolyser at 400 and 580°C was investigated. Light bio-oil compounds and aromatic organic compounds were investigated. The 'bio-oil like' light compounds from leaf and bark biochars 'surfaces were obtained after leaching the chars with a solvent, suitable to dissolve the respective bio-oils. GC/MS was implemented to investigate the leachates. Phenolics, which are potentially harmful toxins, were detected and their concentration shown to be dependent on the char's origin and the char production temperature. Further, to simulate biochars amendment to soils, the chars were leached with water. The water-leached aromatic compounds from leaf and bark biochars were characterized using UV-fluorescence spectroscopy. Those results suggested that biochars contain leachable compounds of which the nature and amount is dependent on the biomass feedstock, pyrolysis temperature and leaching time. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Effect of plant diversity on the diversity of soil organic compounds.

    PubMed

    El Moujahid, Lamiae; Le Roux, Xavier; Michalet, Serge; Bellvert, Florian; Weigelt, Alexandra; Poly, Franck

    2017-01-01

    The effect of plant diversity on aboveground organisms and processes was largely studied but there is still a lack of knowledge regarding the link between plant diversity and soil characteristics. Here, we analyzed the effect of plant identity and diversity on the diversity of extractible soil organic compounds (ESOC) using 87 experimental grassland plots with different levels of plant diversity and based on a pool of over 50 plant species. Two pools of low molecular weight organic compounds, LMW1 and LMW2, were characterized by GC-MS and HPLC-DAD, respectively. These pools include specific organic acids, fatty acids and phenolics, with more organic acids in LMW1 and more phenolics in LMW2. Plant effect on the diversity of LMW1 and LMW2 compounds was strong and weak, respectively. LMW1 richness observed for bare soil was lower than that observed for all planted soils; and the richness of these soil compounds increased twofold when dominant plant species richness increased from 1 to 6. Comparing the richness of LMW1 compounds observed for a range of plant mixtures and for plant monocultures of species present in these mixtures, we showed that plant species richness increases the richness of these ESOC mainly through complementarity effects among plant species associated with contrasted spectra of soil compounds. This could explain previously reported effects of plant diversity on the diversity of soil heterotrophic microorganisms.

  12. Effect of plant diversity on the diversity of soil organic compounds

    PubMed Central

    El Moujahid, Lamiae; Michalet, Serge; Bellvert, Florian; Weigelt, Alexandra; Poly, Franck

    2017-01-01

    The effect of plant diversity on aboveground organisms and processes was largely studied but there is still a lack of knowledge regarding the link between plant diversity and soil characteristics. Here, we analyzed the effect of plant identity and diversity on the diversity of extractible soil organic compounds (ESOC) using 87 experimental grassland plots with different levels of plant diversity and based on a pool of over 50 plant species. Two pools of low molecular weight organic compounds, LMW1 and LMW2, were characterized by GC-MS and HPLC-DAD, respectively. These pools include specific organic acids, fatty acids and phenolics, with more organic acids in LMW1 and more phenolics in LMW2. Plant effect on the diversity of LMW1 and LMW2 compounds was strong and weak, respectively. LMW1 richness observed for bare soil was lower than that observed for all planted soils; and the richness of these soil compounds increased twofold when dominant plant species richness increased from 1 to 6. Comparing the richness of LMW1 compounds observed for a range of plant mixtures and for plant monocultures of species present in these mixtures, we showed that plant species richness increases the richness of these ESOC mainly through complementarity effects among plant species associated with contrasted spectra of soil compounds. This could explain previously reported effects of plant diversity on the diversity of soil heterotrophic microorganisms. PMID:28166250

  13. Phosphorus sorption on marine carbonate sediment: phosphonate as model organic compounds.

    PubMed

    Huang, Xiao-Lan; Zhang, Jia-Zhong

    2011-11-01

    Organophosphonate, characterized by the presence of a stable, covalent, carbon to phosphorus (C-P) bond, is a group of synthetic or biogenic organophosphorus compounds. The fate of these organic phosphorus compounds in the environment is not well studied. This study presents the first investigation on the sorption of phosphorus (P) in the presence of two model phosphonate compounds, 2-aminothylphosphonoic acid (2-AEP) and phosphonoformic acid (PFA), on marine carbonate sediments. In contrast to other organic P compounds, no significant inorganic phosphate exchange was observed in seawater. P was found to adsorb on the sediment only in the presence of PFA, not 2-AEP. This indicated that sorption of P from phosphonate on marine sediment was compound specific. Compared with inorganic phosphate sorption on the same sediments, P sorption from organic phosphorus is much less in the marine environment. Further study is needed to understand the potential role of the organophosphonate compounds in biogeochemical cycle of phosphorus in the environment. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Organic compounds in re-circulated leachates of aerobic biological treated municipal solid waste.

    PubMed

    Franke, Matthias; Jandl, Gerald; Leinweber, Peter

    2006-10-01

    Biodegradation of organic matter is required to reduce the potential of municipal solid waste for producing gaseous emissions and leaching contaminants. Therefore, we studied leachates of an aerobic-treated waste from municipal solids and a sewage sludge mixture that were re-circulated to decrease the concentration of biodegradable organic matter in laboratory-scale reactors. After 12 months, the total organic C and biological and chemical oxygen demands were reduced, indicating the biodegradation of organic compounds in the leachates. Curie-point pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and pyrolysis-field ionization mass spectrometry (Py-FIMS) revealed that phenols, alkylaromatic compounds, N-containing compounds and carbohydrates were the predominate compounds in the leachates and solid waste. Leachate re-circulation led to a higher thermal stability of the residual organic matter as indicated by temperature-resolved Py-FIMS. Admixture of sewage sludge to solid waste was less effective in removing organic compounds from the leachates. It resulted in drastic higher and more bio-resistant loads of organic matter in the leachates and revealed increased proportions of alkylaromatic compounds. The biodegradation of organic matter in leachates, re-circulated through municipal solid waste, offers the potential for improved aerobic waste treatments and should be investigated on a larger scale.

  15. Screening of ground water samples for volatile organic compounds using a portable gas chromatograph

    USGS Publications Warehouse

    Buchmiller, R.C.

    1989-01-01

    A portable gas chromatograph was used to screen 32 ground water samples for volatile organic compounds. Seven screened samples were positive; four of the seven samples had volatile organic substances identified by second-column confirmation. Four of the seven positive, screened samples also tested positive in laboratory analyses of duplicate samples. No volatile organic compounds were detected in laboratory analyses of samples that headspace screening indicated to be negative. Samples that contained volatile organic compounds, as identified by laboratory analysis, and that contained a volatile organic compound present in a standard of selected compounds were correctly identified by using the portable gas chromatography. Comparisons of screened-sample data with laboratory data indicate the ability to detect selected volatile organic compounds at concentrations of about 1 microgram per liter in the headspace of water samples by use of a portable gas chromatography. -Author

  16. Universal HPLC Detector for Hydrophilic Organic Compounds by Means of Total Organic Carbon Detection.

    PubMed

    Ohira, Shin-Ichi; Kaneda, Kyosuke; Matsuzaki, Toru; Mori, Shuta; Mori, Masanobu; Toda, Kei

    2018-06-05

    Most quantifications are achieved by comparison of the signals obtained with the sample to those from a standard. Thus, the purity and stability of the standard are key in chemical analysis. Furthermore, if an analyte standard cannot be obtained, quantification cannot be achieved, even if the chemical structures are identified by a qualification method (e.g., high-resolution mass spectrometry). Herein, we describe a universal and analyte standard-free detector for aqueous-eluent-based high-performance liquid chromatography. This universal carbon detector (UCD) was developed based on total organic carbon detection. Separated analytes were oxidized in-line and converted to carbon dioxide (CO 2 ). Generated CO 2 was transferred into the gas phase and collected into ultrapure water, which was followed by conductivity detection. The system can be applied as a HPLC detector that does not use an organic solvent as an eluent. The system can be calibrated with a primary standard of sodium bicarbonate for organic compounds. The universality and quantification were evaluated with organic compounds, including organic acids, sugars, and amino acids. Furthermore, the system was successfully applied to evaluation of the purity of formaldehyde in formalin solution, and determination of sugars in juices. The results show the universal carbon detector has good universality and can quantify many kinds of organic compounds with a single standard such as sodium bicarbonate.

  17. Reverse Osmosis Processing of Organic Model Compounds and Fermentation Broths

    DTIC Science & Technology

    2006-04-01

    AFRL-ML-TY-TP-2007-4545 POSTPRINT REVERSE OSMOSIS PROCESSING OF ORGANIC MODEL COMPOUNDS AND FERMENTATION BROTHS Robert Diltz...TELEPHONE NUMBER (Include area code) Bioresource Technology 98 (2007) 686–695Reverse osmosis processing of organic model compounds and fermentation broths...December 2005; accepted 31 January 2006 Available online 4 April 2006Abstract Post-treatment of an anaerobic fermentation broth was evaluated using a 150

  18. Presence and distribution of chlorinated organic compounds in streambed sediments, new jersey

    USGS Publications Warehouse

    Stackelberg, P.E.

    1997-01-01

    Concentrations of 18 hydrophobic chlorinated organic compounds in streambed sediments from 100 sites throughout New Jersey were examined to determine (1) which compounds were detected most frequently, (2) whether detection frequencies differed among selected drainage basins, and (3) whether concentrations differed significantly among selected drainage basins. Twelve drainage basins across New Jersey that contain a range of land-use patterns and population densities were selected to represent various types and degrees of development. To ensure an adequate number of samples for statistical comparison among drainage basins, the 12 selected basins were consolidated into seven drainage areas on the basis of similarities in land- use patterns and population densities. Additionally, data for three classes of chlorinated organic compounds in streambed sediments from 255 sites throughout New Jersey were examined to determine whether the presence of these compounds in streambed sediments is related to the type and degree of development within the drainage area of each sampling site. Chlorinated organic compounds detected most frequently within the seven representative drainage areas were DDT, DDE, DDD, chlordane, dieldrin, and PCBs. DDT, DDE, and DDD, which were the most widely distributed organic compounds, were detected in about 60 to 100 percent of the samples from all drainage areas hut one (where the detection rate for these compounds was about 20 to 40 percent). Chlordane and dieldrin were detected in about 80 to 100 percent of samples from highly urbanized and populated drainage areas; detection frequencies for these compounds tended to be smaller in less developed and populated areas. PCBs were detected in about 40 to 85 percent of samples from all drainage areas; detection frequencies were highest in the most heavily developed and populated areas. Analysis of variance on rank-transformed organic compound concentrations normalized to sediment organic carbon content

  19. Precipitate hydrolysis process for the removal of organic compounds from nuclear waste slurries

    DOEpatents

    Doherty, J.P.; Marek, J.C.

    1987-02-25

    A process for removing organic compounds from a nuclear waste slurry comprising reacting a mixture of radioactive waste precipitate slurry and an acid in the presence of a catalytically effective amount of a copper(II) catalyst whereby the organic compounds in the precipitate slurry are hydrolyzed to form volatile organic compounds which are separated from the reacting mixture. The resulting waste slurry, containing less than 10 percent of the original organic compounds, is subsequently blended with high level radioactive sludge land transferred to a vitrification facility for processing into borosilicate glass for long-term storage. 2 figs., 3 tabs.

  20. Transport, behavior, and fate of volatile organic compounds in streams

    USGS Publications Warehouse

    Rathbun, R.E.

    1998-01-01

    Volatile organic compounds (VOCs) are compounds with chemical and physical properties that allow the compounds to move freely between the water and air phases of the environment. VOCs are widespread in the environment because of this mobility. Many VOCs have properties making them suspected or known hazards to the health of humans and aquatic organisms. Consequently, understanding the processes affecting the concentration and distribution VOCs in the environment is necessary. The U.S. Geological Survey selected 55 VOCs for study. This report reviews the characteristics of the various process that could affect the transport, behavior, and fate of these VOCs in streams.

  1. Catalytic Destruction Of Toxic Organic Compounds

    NASA Technical Reports Server (NTRS)

    Voecks, Gerald E.

    1990-01-01

    Proposed process disposes of toxic organic compounds in contaminated soil or carbon beds safely and efficiently. Oxidizes toxic materials without producing such other contaminants as nitrogen oxides. Using air, fuel, catalysts, and steam, system consumes less fuel and energy than decontamination processes currently in use. Similar process regenerates carbon beds used in water-treatment plants.

  2. 40 CFR 60.622 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... compounds. 60.622 Section 60.622 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected petroleum solvent dry cleaning dryer that is installed at a petroleum dry cleaning plant after December 14, 1982...

  3. 40 CFR 60.622 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... compounds. 60.622 Section 60.622 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected petroleum solvent dry cleaning dryer that is installed at a petroleum dry cleaning plant after December 14, 1982...

  4. 40 CFR 60.622 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... compounds. 60.622 Section 60.622 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected petroleum solvent dry cleaning dryer that is installed at a petroleum dry cleaning plant after December 14, 1982...

  5. Individual organic compounds in water extracts from podzolic soils of the Komi Republic

    NASA Astrophysics Data System (ADS)

    Shamrikova, E. V.; Punegov, V. V.; Gruzdev, I. V.; Vanchikova, E. V.; Vetoshkina, A. A.

    2012-10-01

    The contents of organic compounds in water extracts from organic horizons of loamy soils with different water contents from the medium taiga zone of the Komi Republic were determined by gas-liquid chromatography and chromatography-mass spectrometry. The mass concentration of organic carbon in the extracts was in the range of 290-330 mg/dm3; the mass fraction of the carbon from the identified compounds was 0.5-1.9%. Hydrocarbons made up about 60% of the total identified compounds; acids and their derivatives composed less than 40%. Most of the acids (40-70%) were aliphatic hydroxy acids. The tendencies in the formation of different classes of organic compounds were revealed depending on the degree of the soil hydromorphism. The acid properties of the water-soluble compounds were studied by pK spectroscopy. Five groups of compounds containing acid groups with similar pKa values were revealed. The compounds containing groups with pKa < 4.0 were predominant. The increase in the surface wetting favored the formation of compounds with pKa 3.2-4.0 and 7.4-8.4.

  6. Assessment of volatile organic compound emissions from ecosystems of China

    NASA Astrophysics Data System (ADS)

    Klinger, L. F.; Li, Q.-J.; Guenther, A. B.; Greenberg, J. P.; Baker, B.; Bai, J.-H.

    2002-11-01

    Isoprene, monoterpene, and other volatile organic compound (VOC) emissions from grasslands, shrublands, forests, and peatlands in China were characterized to estimate their regional magnitudes and to compare these emissions with those from landscapes of North America, Europe, and Africa. Ecological and VOC emission sampling was conducted at 52 sites centered in and around major research stations located in seven different regions of China: Inner Mongolia (temperate), Changbai Mountain (boreal-temperate), Beijing Mountain (temperate), Dinghu Mountain (subtropical), Ailao Mountain (subtropical), Kunming (subtropical), and Xishuangbanna (tropical). Transects were used to sample plant species and growth form composition, leafy (green) biomass, and leaf area in forests representing nearly all the major forest types of China. Leafy biomass was determined using generic algorithms based on tree diameter, canopy structure, and absolute cover. Measurements of VOC emissions were made on 386 of the 541 recorded species using a portable photo-ionization detector method. For 105 species, VOC emissions were also measured using a flow-through leaf cuvette sampling/gas chromatography analysis method. Results indicate that isoprene and monoterpene emissions, as well as leafy biomass, vary systematically along gradients of ecological succession in the same manner found in previous studies in the United States, Canada, and Africa. Applying these results to a regional VOC emissions model, we arrive at a value of 21 Tg C for total annual biogenic VOC emissions from China, compared to 5 Tg C of VOCs released annually from anthropogenic sources there. The isoprene and monoterpene emissions are nearly the same as those reported for Europe, which is comparable in size to China.

  7. The role of hydrology in annual organic carbon loads and terrestrial organic matter export from a midwestern agricultural watershed

    NASA Astrophysics Data System (ADS)

    Dalzell, Brent J.; Filley, Timothy R.; Harbor, Jon M.

    2007-03-01

    Defining the control that hydrology exerts on organic carbon (OC) export at the watershed scale is important for understanding how the source and quantity of OC in streams and rivers is influenced by climate change or by landscape drainage. To this end, molecular (lignin phenol), stable carbon isotope, and dissolved organic carbon (DOC) data were collected over a range of flow conditions to examine the influence of hydrology on annual OC export from an 850 km 2 Midwestern United States agricultural watershed located in west central Indiana. In years 2002 and 2003, modeled annual DOC loads were 19.5 and 14.1 kg ha -1yr -1, while 71% and 85%, respectively, of the total annual OC was exported in flow events occurring during less than 20% of that time. These results highlight the importance of short-duration, high-discharge events (common in smaller watersheds) in controlling annual OC export. Based on reported increases in annual stream discharge coupled with current estimates of DOC export, annual DOC loads in this watershed may have increased by up to 40% over the past 50 years. Molecular (lignin phenol) characterization of quantity and relative degradation state of terrestrial OC shows as much temporal variability of lignin parameters (in high molecular weight dissolved organic carbon) in this one watershed as that demonstrated in previously published studies of dissolved organic matter in the Mississippi and Amazon Rivers. These results suggest that hydrologic variability is at least as important in determining the nature and extent of OC export as geographic variability. Moreover, molecular and bulk stable carbon isotope data from high molecular weight dissolved organic carbon and colloidal organic carbon showed that increased stream flow from the study watershed was responsible for increased export of agriculturally derived OC. When considered in the context of results from other studies that show the importance of flood events and in-stream processing of

  8. Rapid NMR method for the quantification of organic compounds in thin stillage.

    PubMed

    Ratanapariyanuch, Kornsulee; Shen, Jianheng; Jia, Yunhua; Tyler, Robert T; Shim, Youn Young; Reaney, Martin J T

    2011-10-12

    Thin stillage contains organic and inorganic compounds, some of which may be valuable fermentation coproducts. This study describes a thorough analysis of the major solutes present in thin stillage as revealed by NMR and HPLC. The concentration of charged and neutral organic compounds in thin stillage was determined by excitation sculpting NMR methods (double pulse field gradient spin echo). Compounds identified by NMR included isopropanol, ethanol, lactic acid, 1,3-propanediol, acetic acid, succinic acid, glycerophosphorylcholine, betaine, glycerol, and 2-phenylethanol. The concentrations of lactic and acetic acid determined with NMR were comparable to those determined using HPLC. HPLC and NMR were complementary, as more compounds were identified using both methods. NMR analysis revealed that stillage contained the nitrogenous organic compounds betaine and glycerophosphorylcholine, which contributed as much as 24% of the nitrogen present in the stillage. These compounds were not observed by HPLC analysis.

  9. Uptake of organic sulfur and nitrogen compounds by aerosols

    USDA-ARS?s Scientific Manuscript database

    Efforts have been undertaken to monitor and model the uptake of medium-sized organic compounds found above agricultural waste. Field effects performed by our collaborators monitor both the gas phase compounds present in a chicken house in Kentucky; using PILS-IC sampling, the contents of PM2.5 parti...

  10. Characterization of polar organic compounds and source analysis of fine organic aerosols in Hong Kong

    NASA Astrophysics Data System (ADS)

    Li, Yunchun

    Organic aerosols, as an important fraction of airborne particulate mass, significantly affect the environment, climate, and human health. Compared with inorganic species, characterization of individual organic compounds is much less complete and comprehensive because they number in thousands or more and are diverse in chemical structures. The source contributions of organic aerosols are far from being well understood because they can be emitted from a variety of sources as well as formed from photochemical reactions of numerous precursors. This thesis work aims to improve the characterization of polar organic compounds and source apportionment analysis of fine organic carbon (OC) in Hong Kong, which consists of two parts: (1) An improved analytical method to determine monocarboxylic acids, dicarboxylic acids, ketocarboxylic acids, and dicarbonyls collected on filter substrates has been established. These oxygenated compounds were determined as their butyl ester or butyl acetal derivatives using gas chromatography-mass spectrometry. The new method made improvements over the original Kawamura method by eliminating the water extraction and evaporation steps. Aerosol materials were directly mixed with the BF 3/BuOH derivatization agent and the extracting solvent hexane. This modification improves recoveries for both the more volatile and the less water-soluble compounds. This improved method was applied to study the abundances and sources of these oxygenated compounds in PM2.5 aerosol samples collected in Hong Kong under different synoptic conditions during 2003-2005. These compounds account for on average 5.2% of OC (range: 1.4%-13.6%) on a carbon basis. Oxalic acid was the most abundant species. Six C2 and C3 oxygenated compounds, namely oxalic, malonic, glyoxylic, pyruvic acids, glyoxal, and methylglyoxal, dominated this suite of oxygenated compounds. More efforts are therefore suggested to focus on these small compounds in understanding the role of oxygenated

  11. Nitrogen Containing Organic Compounds and Oligomers in Secondary Organic Aerosol Formed by Photooxidation of Isoprene

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nguyen, Tran B.; Laskin, Julia; Laskin, Alexander

    2011-07-06

    Electrospray ionization high-resolution mass spectrometry (ESI HR-MS) was used to probe molecular structures of oligomers in secondary organic aerosol (SOA) generated in laboratory experiments on isoprene photooxidation at low- and high-NOx conditions. Up to 80-90% of the observed products are oligomers and up to 33% are nitrogen-containing organic compounds (NOC). We observe oligomers with up to 8 monomer units in length. Tandem mass spectrometry (MSn) confirms NOC compounds are organic nitrates and elucidates plausible chemical building blocks contributing to oligomer formation. Most organic nitrates are comprised of methylglyceric acid units. Other important multifunctional C2-C5 monomer units are identified including methylglyoxal,more » hydroxyacetone, hydroxyacetic acid, glycolaldehyde, and 2-methyltetrols. The majority of the NOC oligomers contain only one nitrate moiety resulting in a low average N:C ratio of 0.019. Average O:C ratios of the detected SOA compounds are 0.54 under the low-NOx conditions and 0.83 under the high-NOx conditions. Our results underscore the importance of isoprene photooxidation as a source of NOC in organic particulate matter.« less

  12. Self assembly properties of primitive organic compounds

    NASA Technical Reports Server (NTRS)

    Deamer, D. W.

    1991-01-01

    A central event in the origin of life was the self-assembly of amphiphilic, lipid-like compounds into closed microenvironments. If a primitive macromolecular replicating system could be encapsulated within a vesicular membrane, the components of the system would share the same microenvironment, and the result would be a step toward true cellular function. The goal of our research has been to determine what amphiphilic molecules might plausibly have been available on the early Earth to participate in the formation of such boundary structures. To this end, we have investigated primitive organic mixtures present in carbonaceous meteorites such as the Murchison meteorite, which contains 1-2 percent of its mass in the form of organic carbon compounds. It is likely that such compounds contributed to the inventory of organic carbon on the prebiotic earth, and were available to participate in chemical evolution leading to the emergence of the first cellular life forms. We found that Murchison components extracted into non-polar solvent systems are surface active, a clear indication of amphiphilic character. One acidic fraction self-assembles into vesicular membranes that provide permeability barriers to polar solutes. Other evidence indicates that the membranes are bimolecular layers similar to those formed by contemporary membrane lipids. We conclude that bilayer membrane formation by primitive amphiphiles on the early Earth is feasible. However, only a minor fraction of acidic amphiphiles assembles into bilayers, and the resulting membranes require narrowly defined conditions of pH and ionic composition to be stable. It seems unlikely, therefore, that meteoritic infall was a direct source of membrane amphiphiles. Instead, the hydrocarbon components and their derivatives more probably would provide an organic stock available for chemical evolution. Our current research is directed at possible reactions which would generate substantial quantities of membranogenic

  13. The Atmospheric Fate of Organic Nitrogen Compounds

    NASA Astrophysics Data System (ADS)

    Borduas, Nadine

    Organic nitrogen compounds are present in our atmosphere from biogenic and anthropogenic sources and have impacts on air quality and climate. Due to recent advances in instrumentation, these compounds are being detected in the gas and particle phases, raising questions as to their source, processing and sinks in the environment. With their recently identified role as contributors to aerosol formation and growth, their novel large scale use as solvents in carbon capture and storage (CCS) technology and their emissions from cigarette smoke, it is now important to address the gaps in our understanding of the fate of organic nitrogen. Experimentally and theoretically, I studied the chemical atmospheric fate of specific organic nitrogen compounds in the amine, amide and isocyanate families, yielding information that can be used in chemical transport models to assess the fate of this emerging class of atmospheric molecules. I performed kinetic laboratory studies in a smog chamber to measure the room temperature rate coefficient for reaction with the hydroxyl radical of monoethanolamine, nicotine, and five different amides. I employed online-mass spectrometry techniques to quantify the oxidation products. I found that amines react quickly with OH radicals with lifetimes of a few hours under sunlit conditions, producing amides as oxidation products. My studies on amides revealed that they have much longer lifetimes in the atmosphere, ranging from a few hours to a week. Photo-oxidation of amides produces isocyanates and I investigated these mechanisms in detail using ab initio calculations. Furthermore, I experimentally measured isocyanic acid's Henry's Law constant as well as its hydrolysis rate constants to better understand its sinks in the atmosphere. Finally, I re-examined the structure-activity relationship (SAR) of organic nitrogen molecules for improved model parameterizations.

  14. Long-term Monitoring Program Optimization for Chlorinated Volatile Organic Compound Plume, Naval Air Station Brunswick, Maine

    NASA Astrophysics Data System (ADS)

    Calderone, G. M.

    2006-12-01

    A long-term monitoring program was initiated in 1995 at 6 sites at NAS Brunswick, including 3 National Priorities List (Superfund) sites. Primary contaminants of concern include chlorinated volatile organic compounds, including tetrachloroethane, trichloroethene, and vinyl chloride, in addition to metals. More than 80 submersible pumping systems were installed to facilitate sample collection utilizing the low-flow sampling technique. Long-term monitoring of the groundwater is conducted to assess the effectiveness of remedial measures, and monitor changes in contaminant concentrations in the Eastern Plume Operable Unit. Long-term monitoring program activities include quarterly groundwater sampling and analysis at more than 90 wells across 6 sites; surface water, sediment, seep, and leachate sampling and analysis at 3 sites; landfill gas monitoring; well maintenance; engineering inspections of landfill covers and other sites or evidence of stressed vegetation; water level gauging; and treatment plant sampling and analysis. Significant cost savings were achieved by optimizing the sampling network and reducing sampling frequency from quarterly to semi- annual or annual sampling. As part of an ongoing optimization effort, a geostatistical assessment of the Eastern Plume was conducted at the Naval Air Station, Brunswick, Maine. The geostatistical assessment used 40 monitoring points and analytical data collected over 3 years. For this geostatistical assessment, EA developed and utilized a database of analytical results generated during 3 years of long-term monitoring which was linked to a Geographic Information System to enhance data visualization capacity. The Geographic Information System included themes for groundwater volatile organic compound concentration, groundwater flow directions, shallow and deep wells, and immediate access to point-specific analytical results. This statistical analysis has been used by the site decision-maker and its conclusions supported a

  15. Highly stable meteoritic organic compounds as markers of asteroidal delivery

    NASA Astrophysics Data System (ADS)

    Cooper, George; Horz, Friedrich; Spees, Alanna; Chang, Sherwood

    2014-01-01

    Multiple missions to search for water-soluble organic compounds on the surfaces of Solar System bodies are either current or planned and, if such compounds were found, it would be desirable to determine their origin(s). Asteroid or comet material is likely to have been components of all surface environments throughout Solar System history. To simulate the survival of meteoritic compounds both during impacts with planetary surfaces and under subsequent (possibly) harsh ambient conditions, we subjected known meteoritic compounds to comparatively high impact-shock pressures (>30 GPa) and/or to extremely oxidizing/corrosive acid solution. Consistent with past impact experiments, α-amino acids survived only at trace levels above ∼18 GPa. Polyaromatic hydrocarbons (PAHs) survived at levels of 4-8% at a shock pressure of 36 GPa. Lower molecular weight sulfonic and phosphonic acids (S&P) had the highest degree of impact survival of all tested compounds at higher pressures. Oxidation of compounds was done with a 3:1 mixture of HCl:HNO3, a solution that generates additional strong oxidants such as Cl2 and NOCl. Upon oxidation, keto acids and α-amino acids were the most labile compounds with proline as a significant exception. Some fraction of the other compounds, including non-α amino acids and dicarboxylic acids, were stable during 16-18 hours of oxidation. However, S&P quantitatively survived several months (at least) under the same conditions. Such results begin to build a profile of the more robust meteoritic compounds: those that may have survived, i.e., may be found in, the more hostile Solar System environments. In the search for organic compounds, one current mission, NASA's Mars Science Laboratory (MSL), will use analytical procedures similar to those of this study and those employed previously on Earth to identify many of the compounds described in this work. The current results may thus prove to be directly relevant to potential findings of MSL and other

  16. Mathematical modeling of atmospheric fine particle-associated primary organic compound concentrations

    NASA Astrophysics Data System (ADS)

    Rogge, Wolfgang F.; Hildemann, Lynn M.; Mazurek, Monica A.; Cass, Glen R.; Simoneit, Bernd R. T.

    1996-08-01

    An atmospheric transport model has been used to explore the relationship between source emissions and ambient air quality for individual particle phase organic compounds present in primary aerosol source emissions. An inventory of fine particulate organic compound emissions was assembled for the Los Angeles area in the year 1982. Sources characterized included noncatalyst- and catalyst-equipped autos, diesel trucks, paved road dust, tire wear, brake lining dust, meat cooking operations, industrial oil-fired boilers, roofing tar pots, natural gas combustion in residential homes, cigarette smoke, fireplaces burning oak and pine wood, and plant leaf abrasion products. These primary fine particle source emissions were supplied to a computer-based model that simulates atmospheric transport, dispersion, and dry deposition based on the time series of hourly wind observations and mixing depths. Monthly average fine particle organic compound concentrations that would prevail if the primary organic aerosol were transported without chemical reaction were computed for more than 100 organic compounds within an 80 km × 80 km modeling area centered over Los Angeles. The monthly average compound concentrations predicted by the transport model were compared to atmospheric measurements made at monitoring sites within the study area during 1982. The predicted seasonal variation and absolute values of the concentrations of the more stable compounds are found to be in reasonable agreement with the ambient observations. While model predictions for the higher molecular weight polycyclic aromatic hydrocarbons (PAH) are in agreement with ambient observations, lower molecular weight PAH show much higher predicted than measured atmospheric concentrations in the particle phase, indicating atmospheric decay by chemical reactions or evaporation from the particle phase. The atmospheric concentrations of dicarboxylic acids and aromatic polycarboxylic acids greatly exceed the contributions that

  17. Process for reducing organic compounds with calcium, amine, and alcohol

    DOEpatents

    Benkeser, Robert A.; Laugal, James A.; Rappa, Angela

    1985-01-01

    Olefins are produced by contacting an organic compound having at least one benzene ring with calcium metal, ethylenediamine, a low molecular weight aliphatic alcohol, and optionally a low molecular weight aliphatic primary amine, and/or an inert, abrasive particulate substance. The reduction is conducted at temperatures ranging from about -10.degree. C. to about 30.degree. C. or somewhat higher. Substantially all of the organic compounds are converted to corresponding cyclic olefins, primarily diolefins.

  18. Process for reducing organic compounds with calcium, amine, and alcohol

    DOEpatents

    Benkeser, R.A.; Laugal, J.A.; Rappa, A.

    1985-08-06

    Olefins are produced by contacting an organic compound having at least one benzene ring with calcium metal, ethylenediamine, a low molecular weight aliphatic alcohol, and optionally a low molecular weight aliphatic primary amine, and/or an inert, abrasive particulate substance. The reduction is conducted at temperatures ranging from about [minus]10 C to about 30 C or somewhat higher. Substantially all of the organic compounds are converted to corresponding cyclic olefins, primarily diolefins.

  19. Removal of volatile organic compounds using amphiphilic cyclodextrin-coated polypropylene.

    PubMed

    Lumholdt, Ludmilla; Fourmentin, Sophie; Nielsen, Thorbjørn T; Larsen, Kim L

    2014-01-01

    Polypropylene nonwovens were functionalised using a self-assembled, amphiphilic cyclodextrin coating and the potential for water purification by removal of pollutants was studied. As benzene is one of the problematic compounds in the Water Framework Directive, six volatile organic compounds (benzene and five benzene-based substances) were chosen as model compounds. The compounds were tested as a mixture in order to provide a more realistic situation since the wastewater will be a complex mixture containing multiple pollutants. The volatile organic compounds are known to form stable inclusion complexes with cyclodextrins. Six different amphiphilic cyclodextrin derivatives were synthesised in order to elucidate whether or not the uptake abilities of the coating depend on the structure of the derivative. Headspace gas chromatography was used for quantification of the uptake exploiting the volatile nature of benzene and its derivatives. The capacity was shown to increase beyond the expected stoichiometries of guest-host complexes with ratios of up to 16:1.

  20. Biogenic volatile organic compounds - small is beautiful

    NASA Astrophysics Data System (ADS)

    Owen, S. M.; Asensio, D.; Li, Q.; Penuelas, J.

    2012-12-01

    While canopy and regional scale flux measurements of biogenic volatile organic compounds (bVOCs) are essential to obtain an integrated picture of total compound reaching the atmosphere, many fascinating and important emission details are waiting to be discovered at smaller scales, in different ecological and functional compartments. We concentrate on bVOCs below ground to <2m above ground level. Emissions at leaf scale are well documented and widely presented, and are not discussed here. Instead we describe some details of recent research on rhizosphere bVOCs, and bVOCs associated with pollination of flowers. Although bVOC emissions from soil surfaces are small, bVOCs are exuded by roots of some plant species, and can be extracted from decaying litter. Naturally occurring monoterpenes in the rhizosphere provide a specialised carbon source for micro-organisms, helping to define the micro-organism community structure, and impacting on nutrient cycles which are partly controlled by microorganisms. Naturally occurring monoterpenes in the soil system could also affect the aboveground structure of ecosystems because of their role in plant defence strategies and as mediating chemicals in allelopathy. A gradient of monoterpene concentration was found in soil around Pinus sylvestris and Pinus halepensis, decreasing with distance from the tree. Some compounds (α-pinene, sabinene, humulene and caryophyllene) in mineral soil were linearly correlated with the total amount of each compound in the overlying litter, indicating that litter might be the dominant source of these compounds. However, α-pinene did not fall within the correlation, indicating a source other than litter, probably root exudates. We also show that rhizosphere bVOCs can be a carbon source for soil microbes. In a horizontal gradient from Populus tremula trees, microbes closest to the tree trunk were better enzymatically equipped to metabolise labeled monoterpene substrate. Monoterpenes can also increase the

  1. Analysis of volatile organic compounds from illicit cocaine samples

    NASA Astrophysics Data System (ADS)

    Robins, W. H.; Wright, Bob W.

    1994-10-01

    Detection of illicit cocaine hydrochloride shipments can be improved if there is a greater understanding of the identity and quantity of volatile compounds present. This study provides preliminary data concerning the volatile organic compounds detected in a limited set of cocaine hydrochloride samples. In all cases, cocaine was one of the major volatile compounds detected. Other tropeines were detected in almost all samples. Low concentrations of compounds which may be residues of processing solvents were observed in some samples. The equilibrium emissivity of cocaine from cocaine hydrochloride was investigated and a value of 83 parts-per-trillion was determined.

  2. Simplified Production of Organic Compounds Containing High Enantiomer Excesses

    NASA Technical Reports Server (NTRS)

    Cooper, George W. (Inventor)

    2015-01-01

    The present invention is directed to a method for making an enantiomeric organic compound having a high amount of enantiomer excesses including the steps of a) providing an aqueous solution including an initial reactant and a catalyst; and b) subjecting said aqueous solution simultaneously to a magnetic field and photolysis radiation such that said photolysis radiation produces light rays that run substantially parallel or anti-parallel to the magnetic field passing through said aqueous solution, wherein said catalyst reacts with said initial reactant to form the enantiomeric organic compound having a high amount of enantiomer excesses.

  3. Temperature sensitivity of organic compound destruction in SCWO process.

    PubMed

    Tan, Yaqin; Shen, Zhemin; Guo, Weimin; Ouyang, Chuang; Jia, Jinping; Jiang, Weili; Zhou, Haiyun

    2014-03-01

    To study the temperature sensitivity of the destruction of organic compounds in supercritical water oxidation process (SCWO), oxidation effects of twelve chemicals in supercritical water were investigated. The SCWO reaction rates of different compounds improved to varying degrees with the increase of temperature, so the highest slope of the temperature-effect curve (imax) was defined as the maximum ratio of removal ratio to working temperature. It is an important index to stand for the temperature sensitivity effect in SCWO. It was proven that the higher imax is, the more significant the effect of temperature on the SCWO effect is. Since the high-temperature area of SCWO equipment is subject to considerable damage from fatigue, the temperature is of great significance in SCWO equipment operation. Generally, most compounds (imax > 0.25) can be completely oxidized when the reactor temperature reaches 500°C. However, some compounds (imax > 0.25) need a higher temperature for complete oxidation, up to 560°C. To analyze the correlation coefficients between imax and various molecular descriptors, a quantum chemical method was used in this study. The structures of the twelve organic compounds were optimized by the Density Functional Theory B3LYP/6-311G method, as well as their quantum properties. It was shown that six molecular descriptors were negatively correlated to imax while other three descriptors were positively correlated to imax. Among them, dipole moment had the greatest effect on the oxidation thermodynamics of the twelve organic compounds. Once a correlation between molecular descriptors and imax is established, SCWO can be run at an appropriate temperature according to molecular structure. Copyright © 2014 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  4. Electroreduction of Halogenated Organic Compounds

    NASA Astrophysics Data System (ADS)

    Rondinini, Sandra; Vertova, Alberto

    The electroreductive cleavage of the carbon-halogen bond in halogenated organic compounds has been extensively studied for more than 70 years, since it is prodromal to a large variety of synthetic applications in organic electrochemistry. Over the years the research interest have progressively included the environmental applications, since several organic halocompounds are known to have (or have had) a serious environmental impact because of their (present or past) wide use as cleaning agents, herbicides, cryogenic fluids, reagents (e.g. allyl and vinyl monomers) for large production materials, etc. Recent studies have also demonstrated the wide spread out- and in-door-presence of volatile organic halides, although at low level, in connexion with residential and non-residential (e.g. stores, restaurants and transportation) activities. In this context, the detoxification of emissions to air, water and land by the selective removal of the halogen group represents a valid treatment route, which, although not leading to the complete mineralization of the pollutants, produces less harmful streams to be easily treated by electrochemical or conventional techniques. The electroreduction process is analysed and discussed in terms of electrode material, reaction medium, cell design and operation, and of substrate classification.

  5. Identification of organic compounds in landfill leachate treated by advanced oxidation processes.

    PubMed

    Scandelai, Ana Paula Jambers; Sloboda Rigobello, Eliane; Oliveira, Beatriz Lopes Corso de; Tavares, Célia Regina Granhen

    2017-11-27

    Landfill leachates are considered to be complex effluents of a variable composition containing many biorecalcitrant and highly toxic compounds. Considering the shortage of studies concerning the treatment of landfill leachates using ozone, as well as its combination with catalysts, the aim of this paper was to identify the organic compounds in this effluent treated with advanced oxidation processes (AOPs) of ozonation (O 3 ), and heterogeneous catalytic ozonation with TiO 2 (O 3 /TiO 2 ) and with ZnO (O 3 /ZnO). In addition, this study sought to assess the efficiency of the removal of the organic matter present in the leachate. For the pre- and post-AOPs, the leachate was characterized through physicochemical parameters and identification of organic compounds using gas chromatography coupled to the mass spectrometry (GC-MS). The three processes studied (O 3 , O 3 /TiO 2 , and O 3 /ZnO) presented color removal, turbidity, BOD above 95%, and lower COD removals (19%, 24%, and 33%, respectively). All AOPs studied promoted a similar reduction of organic compounds from leachate, some of which with toxic and carcinogenic potential, such as p-cresol, bisphenol A, atrazine, and hexazinone. In addition, upon the removal of organic matter and organic compounds, the heterogeneous catalytic ozonation processes proved more efficient than the process carried out only with ozone.

  6. Effect of water saturation in soil organic matter on the partition of organic compounds

    USGS Publications Warehouse

    Rutherford, D.W.; Chlou, G.T.

    1992-01-01

    The sorption of benzene, trichloroethylene, and carbon tetrachloride at room temperature from water solution and from vapor on two high-organic-content soils (peat and muck) was determined in order to evaluate the effect of water saturation on the solute partition in soil organic matter (SOM). The uptake of water vapor was similarly determined to define the amounts of water in the saturated soil samples. In such high-organic-content soils the organic vapor sorption and the respective solute sorption from water exhibit linear isotherms over a wide range of relative concentrations. This observation, along with the low BET surface areas of the samples, suggests that partition in the SOM of the samples is the dominant process in the uptake of these liquids. A comparison of the sorption from water solution and from vapor phase shows that water saturation reduces the sorption (partition) efficiency of SOM by ?? 42%; the saturated water content is ??38% by weight of dry SOM. This reduction is relatively small when compared with the almost complete suppression by water of organic compound adsorption on soil minerals. While the effect of water saturation on solute uptake by SOM is much expected in terms of solute partition in SOM, the influence of water on the solubility behavior of polar SOM can be explained only qualitatively by regular solution theory. The results suggest that the major effect of water in a drying-wetting cycle on the organic compound uptake by normal low-organic-content soils (and the associated compound's activity) is the suppression of adsorption by minerals rather than the mitigation of the partition effect in SOM.

  7. Organic micropollutants in the Yangtze River: seasonal occurrence and annual loads.

    PubMed

    Qi, Weixiao; Müller, Beat; Pernet-Coudrier, Benoit; Singer, Heinz; Liu, Huijuan; Qu, Jiuhui; Berg, Michael

    2014-02-15

    Twenty percent of the water run-off from China's land surface drains into the Yangtze River and carries the sewage of approximately 400 million people out to sea. The lower stretch of the Yangtze therefore offers the opportunity to assess the pollutant discharge of a huge population. To establish a comprehensive assessment of micropollutants, river water samples were collected monthly from May 2009 to June 2010 along a cross-section at the lowermost hydrological station of the Yangtze River not influenced by the tide (Datong Station, Anhui province). Following a prescreening of 268 target compounds, we examined the occurrence, seasonal variation, and annual loads of 117 organic micropollutants, including 51 pesticides, 43 pharmaceuticals, 7 household and industrial chemicals, and 16 polycyclic aromatic hydrocarbons (PAHs). During the 14-month study, the maximum concentrations of particulate PAHs (1-5 μg/g), pesticides (11-284 ng/L), pharmaceuticals (5-224 ng/L), and household and industrial chemicals (4-430 ng/L) were generally lower than in other Chinese rivers due to the dilution caused of the Yangtze River's average water discharge of approximately 30,000 m(3)/s. The loads of most pesticides, anti-infectives, and PAHs were higher in the wet season compared to the dry season, which was attributed to the increased agricultural application of chemicals in the summer, an elevated water discharge through the sewer systems and wastewater treatment plants (WWTP) as a result of high hydraulic loads and the related lower treatment efficiency, and seasonally increased deposition from the atmosphere and runoff from the catchment. The estimated annual load of PAHs in the river accounted for some 4% of the total emission of PAHs in the whole Yangtze Basin. Furthermore, by using sucralose as a tracer for domestic wastewater, we estimate a daily disposal of approximately 47 million m(3) of sewage into the river, corresponding to 1.8% of its average hydraulic load. In summary

  8. Architectural Coatings: National Volatile Organic Compounds Emission Standards

    EPA Pesticide Factsheets

    Read about the section 183(e) rule for volatile organic compounds for architectural coatings. Read the rule summary and history, find the code of federal regulations test, and additional documents, including compliance information.

  9. Leveraging the beneficial compounds of organic and pasture milk

    USDA-ARS?s Scientific Manuscript database

    Much discussion has arisen over the possible benefits of organic food, including milk. Organic milk comes from cows that are on pasture during the growing season, and would be expected to contain some compounds that are not found in animals receiving conventional feed, or at higher concentrations. ...

  10. Detection, composition and treatment of volatile organic compounds from waste treatment plants.

    PubMed

    Font, Xavier; Artola, Adriana; Sánchez, Antoni

    2011-01-01

    Environmental policies at the European and global level support the diversion of wastes from landfills for their treatment in different facilities. Organic waste is mainly treated or valorized through composting, anaerobic digestion or a combination of both treatments. Thus, there are an increasing number of waste treatment plants using this type of biological treatment. During waste handling and biological decomposition steps a number of gaseous compounds are generated or removed from the organic matrix and emitted. Different families of Volatile Organic Compounds (VOC) can be found in these emissions. Many of these compounds are also sources of odor nuisance. In fact, odors are the main source of complaints and social impacts of any waste treatment plant. This work presents a summary of the main types of VOC emitted in organic waste treatment facilities and the methods used to detect and quantify these compounds, together with the treatment methods applied to gaseous emissions commonly used in composting and anaerobic digestion facilities.

  11. Detection, Composition and Treatment of Volatile Organic Compounds from Waste Treatment Plants

    PubMed Central

    Font, Xavier; Artola, Adriana; Sánchez, Antoni

    2011-01-01

    Environmental policies at the European and global level support the diversion of wastes from landfills for their treatment in different facilities. Organic waste is mainly treated or valorized through composting, anaerobic digestion or a combination of both treatments. Thus, there are an increasing number of waste treatment plants using this type of biological treatment. During waste handling and biological decomposition steps a number of gaseous compounds are generated or removed from the organic matrix and emitted. Different families of Volatile Organic Compounds (VOC) can be found in these emissions. Many of these compounds are also sources of odor nuisance. In fact, odors are the main source of complaints and social impacts of any waste treatment plant. This work presents a summary of the main types of VOC emitted in organic waste treatment facilities and the methods used to detect and quantify these compounds, together with the treatment methods applied to gaseous emissions commonly used in composting and anaerobic digestion facilities. PMID:22163835

  12. Oceanic Emissions and Atmospheric Depositions of Volatile Organic Compounds

    NASA Astrophysics Data System (ADS)

    Yang, M.; Blomquist, B.; Beale, R.; Nightingale, P. D.; Liss, P. S.

    2015-12-01

    Atmospheric volatile organic compounds (VOCs) affect the tropospheric oxidative capacity due to their ubiquitous abundance and relatively high reactivity towards the hydroxyal radical. Over the ocean and away from terrestrial emission sources, oxygenated volatile organic compounds (OVOCs) make up a large fraction of VOCs as airmasses age and become more oxidized. In addition to being produced or destroyed in the marine atmosphere, OVOCs can also be emitted from or deposited to the surface ocean. Here we first present direct air-sea flux measurements of three of the most abundant OVOCs - methanol, acetone, and acetaldehyde, by the eddy covariance technique from two cruises in the Atlantic: the Atlantic Meridional Transect in 2012 and the High Wind Gas Exchange Study in 2013. The OVOC mixing ratios were quantified by a high resolution proton-reaction-transfer mass spectrometer with isotopically labeled standards and their air-sea (net) fluxes were derived from the eddy covariance technique. Net methanol flux was consistently from the atmosphere to the surface ocean, while acetone varied from supersaturation (emission) in the subtropics to undersaturation (deposition) in the higher latitudes of the North Atlantic. The net air-sea flux of acetaldehyde is near zero through out the Atlantic despite the apparent supersaturation of this compound in the surface ocean. Knowing the dissolved concentrations and in situ production rates of these compounds in seawater, we then estimate their bulk atmospheric depositions and oceanic emissions. Lastly, we summarize the state of knowledge on the air-sea transport of a number of organic gasses, and postulate the magnitude and environmental impact of total organic carbon transfer between the ocean and the atmosphere.

  13. Dosimeter for monitoring vapors and aerosols of organic compounds

    DOEpatents

    Vo-Dinh, Tuan

    1987-01-01

    A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique.

  14. Anticancer and cancer preventive compounds from edible marine organisms.

    PubMed

    Correia-da-Silva, Marta; Sousa, Emília; Pinto, Madalena M M; Kijjoa, Anake

    2017-10-01

    A direct impact of food on health, which demonstrates that dietary habit is one of the most important determinants of chronic diseases such as cancers, has led to an increased interest of the consumers toward natural bioactive compounds as functional ingredients or nutraceuticals. Epidemiological studies revealed that the populations of many Asian countries with high consumption of fish and seafood have low prevalence of particular type of cancers such as lung, breast, colorectal and prostate cancers. This observation has led to extensive investigations of the benefits of compounds present in edible marine organisms such as fish, marine invertebrates (mollusks, echinoderms) and marine algae as cancer chemopreventive agents. Interestingly, many of these marine organisms not only constitute as seafood delicacy but also as ingredients used in folk medicine of some East and Southeast Asian countries. The results of the investigations on extracts and compounds from fish (cods, anchovy, eel and also fish protein hydrolysates), mollusks (mussel, oyster, clams and abalone), as well as from sea cucumbers on the in vivo/in vitro anticancer/antitumor activities can, in part, support the health benefits of these edible marine organisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Sulfur organic compounds in bottom sediments of the eastern Gulf of Finland.

    PubMed

    Khoroshko, Larisa O; Petrova, Varvara N; Takhistov, Viatcheslav V; Viktorovskii, Igor V; Lahtiperä, Mirja; Paasivirta, Jaakko

    2007-09-01

    Despite the large number of studies on the forms of sulfur in marine deposits, investigations on sulfur organic compounds are still rare. It is known that the processes leading to formation of intermediate and final sulfur compounds (including organic ones) in modern deposits are the results of microbiological transformation of sulfur containing proteins, as well as the microbiological reduction of sulfate ions. The latter are finally reduced by anaerobic sulfate-reducing bacteria to H2S, HS- and S2-; the total sum of these is referred to as 'hydrogen sulfide' in chemical oceanography. Further, the formation of reduced sulfur organic derivatives (sulfides and polysulfides) is the result of interaction of the organic substance destruction products with the sulfide ions. In such cases, the main source of organic substances, as well as sulfates for the sulfur reducing processes, is the pore water in the sediments. The choice of the target of our study is based on the fact that the eastern part of the Gulf of Finland water area receives the bulk of the anthropogenic load of the St. Petersburg region. Low vertical intermixing of the water thickness is observed there (thus creating a deficiency of oxygen near the bottom), and the bottom sea current transfers the polluted salty water of the Baltic Sea into the Neva Bay. The whole of the above are the preconditions for the formation of sulfur-bearing organic compounds. A great number of bottom sediment samples for analytical surveys were collected in the Eastern Gulf of Finland during research expeditions in the years of 1997 and 2001. These were screened for structures of sulfur organic microcontaminants, including organic forms of sulfur, using advanced instrumentation and experienced personnel in our two, cooperating laboratories. This work is a part of the research being carried out on organic micro-admixtures present in bottom sediments, and is the summary of our findings on previously unstudied sulfur organic

  16. Organic compounds in produced waters from coalbed natural gas wells in the Powder River Basin, Wyoming, USA

    USGS Publications Warehouse

    Orem, W.H.; Tatu, C.A.; Lerch, H.E.; Rice, C.A.; Bartos, T.T.; Bates, A.L.; Tewalt, S.; Corum, M.D.

    2007-01-01

    The organic composition of produced water samples from coalbed natural gas (CBNG) wells in the Powder River Basin, WY, sampled in 2001 and 2002 are reported as part of a larger study of the potential health and environmental effects of organic compounds derived from coal. The quality of CBNG produced waters is a potential environmental concern and disposal problem for CBNG producers, and no previous studies of organic compounds in CBNG produced water have been published. Organic compounds identified in the produced water samples included: phenols, biphenyls, N-, O-, and S-containing heterocyclic compounds, polycyclic aromatic hydrocarbons (PAHs), aromatic amines, various non-aromatic compounds, and phthalates. Many of the identified organic compounds (phenols, heterocyclic compounds, PAHs) are probably coal-derived. PAHs represented the group of organic compounds most commonly observed. Concentrations of total PAHs ranged up to 23 ??g/L. Concentrations of individual compounds ranged from about 18 to <0.01 ??g/L. Temporal variability of organic compound concentrations was documented, as two wells with relatively high organic compound contents in produced water in 2001 had much lower concentrations in 2002. In many areas, including the PRB, coal strata provide aquifers for drinking water wells. Organic compounds observed in produced water are also likely present in drinking water supplied from wells in the coal. Some of the organic compounds identified in the produced water samples are potentially toxic, but at the levels measured in these samples are unlikely to have acute health effects. The human health effects of low-level, chronic exposure to coal-derived organic compounds in drinking water are currently unknown. Continuing studies will evaluate possible toxic effects from low level, chronic exposure to coal-derived organic compounds in drinking water supplies.

  17. Nitrate radicals and biogenic volatile organic compounds: oxidation, mechanisms, and organic aerosol

    EPA Science Inventory

    Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO3) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 d...

  18. POTENTIAL EMISSIONS OF HAZARDOUS ORGANIC COMPOUNDS FROM SEWAGE SLUDGE INCINERATION

    EPA Science Inventory

    Laboratory thermal decomposition studies were undertaken to evaluate potential organic emissions from sewage sludge incinerators. Precisely controlled thermal decomposition experiments were conducted on sludge spiked with mixtures of hazardous organic compounds, on the mixtures o...

  19. Synthesis of fluorinated organic compounds using oxygen difluoride

    NASA Technical Reports Server (NTRS)

    Toy, M. S.

    1971-01-01

    Oxygen difluoride synthesis is a much simpler, higher-yield procedure than reactions originally followed to synthesize various fluorinated organic compounds. Extreme care is taken in working with oxygen difluoride as its reactions present severe explosion hazard.

  20. Dosimeter for monitoring vapors and aerosols of organic compounds

    DOEpatents

    Vo-Dinh, T.

    1987-07-14

    A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique. 7 figs.

  1. Investigation of second-order hyperpolarizability of some organic compounds

    NASA Astrophysics Data System (ADS)

    Tajalli, H.; Zirak, P.; Ahmadi, S.

    2003-04-01

    In this work, we have measured the second order hyperpolarizability of some organic materials with (EFISH) method and also calculated the second order hyperpolarizability of 13 organic compound with Mopac6 software and investigated the different factors that affect the amount of second order hyperpolarizability and ways to increase it.

  2. Annual cycle of size-resolved organic aerosol characterization in an urbanized desert environment

    NASA Astrophysics Data System (ADS)

    Cahill, Thomas M.

    2013-06-01

    Studies of size-resolved organic speciation of aerosols are still relatively rare and are generally only conducted over short durations. However, size-resolved organic data can both suggest possible sources of the aerosols and identify the human exposure to the chemicals since different aerosol sizes have different lung capture efficiencies. The objective of this study was to conduct size-resolved organic aerosol speciation for a calendar year in Phoenix, Arizona to determine the seasonal variations in both chemical concentrations and size profiles. The results showed large seasonal differences in combustion pollutants where the highest concentrations were observed in winter. Summertime aerosols have a greater proportion of biological compounds (e.g. sugars and fatty acids) and the biological compounds represent the largest fraction of the organic compounds detected. These results suggest that standard organic carbon (OC) measurements might be heavily influenced by primary biological compounds particularly if the samples are PM10 and TSP samples. Several large dust storms did not significantly alter the organic aerosol profile since Phoenix resides in a dusty desert environment, so the soil and plant tracer of trehalose was almost always present. The aerosol size profiles showed that PAHs were generally most abundant in the smallest aerosol size fractions, which are most likely to be captured by the lung, while the biological compounds were almost exclusively found in the coarse size fraction.

  3. Organic compounds in indoor air—their relevance for perceived indoor air quality?

    NASA Astrophysics Data System (ADS)

    Wolkoff, Peder; Nielsen, Gunnar D.

    It is generally believed that indoor air pollution, one way or another may cause indoor air complaints. However, any association between volatile organic compounds (VOCs) concentrations and increase of indoor climate complaints, like the sick-building syndrome symptoms, is not straightforward. The reported symptom rates of, in particular, eye and upper airway irritation cannot generally be explained by our present knowledge of common chemically non-reactive VOCs measured indoors. Recently, experimental evidence has shown those chemical reactions between ozone (either with or without nitrogen dioxide) and unsaturated organic compounds (e.g. from citrus and pine oils) produce strong eye and airway irritating species. These have not yet been well characterised by conventional sampling and analytical techniques. The chemical reactions can occur indoors, and there is indirect evidence that they are associated with eye and airway irritation. However, many other volatile and non-volatile organic compounds have not generally been measured which could equally well have potent biological effects and cause an increase of complaint rates, and posses a health/comfort risk. As a consequence, it is recommended to use a broader analytical window of organic compounds than the classic VOC window as defined by the World Health Organisation. It may include hitherto not yet sampled or identified intermediary species (e.g., radicals, hydroperoxides and ionic compounds like detergents) as well as species deposited onto particles. Additionally, sampling strategies including emission testing of building products should carefully be linked to the measurement of organic compounds that are expected, based on the best available toxicological knowledge, to have biological effects at indoor concentrations.

  4. Hydrophobic Organic Compounds in Hydraulic Fracturing Flowback Waters: Identification and Source Apportionment

    NASA Astrophysics Data System (ADS)

    Plata, D.; Shregglman, K.; Elsner, M.; Getzinger, G.; Ferguson, L.; Drollette, B.; Karatum, O.; Nelson, R. K.; Reddy, C. M.

    2014-12-01

    Current hydraulic fracturing technologies rely on organic chemicals to serve multiple critical functions, including corrosion inhibition, in situ gel formation, and friction reduction. While industrial users have disclosed several hundreds of compound and mixture identities, it is unclear which of these are used and where, in what proportion, and with what frequency. Furthermore, while flowback and production waters contain both fracturing additive and geogenic compounds, they may contain potential reaction byproducts as well. Here, we identified several hundred organic compounds present in six hydraulic fracturing flowback waters over the Fayetteville shale. Identifications were made via non-target analysis using two-dimensional gas chromatography with time of flight mass spectrometry for hydrophobic organic compounds and liquid chromatography- orbitrap mass spectrometry. Compound identities were confirmed using purchased standards when available. Using the SkyTruth database and the Waxman list of disclosed compounds, we assigned compounds as either fracturing-fluid-derived or geogenic (or both), or a putative transformation products thereof. Several unreported halogenated compounds were detected, including chlorinated, brominated, and iodated species that have no known natural sources. Control studies indicated that these could not be formed under typical laboratory or field storage conditions, suggesting that halogenation reactions may give rise to novel compounds in the subsurface, presumably via reaction between fracturing fluid additives and shale-derived brines. Further, the six samples were strikingly heterogeneous, reflecting the diversity in fracturing fluid composition and flowback handling procedures at the time of the study.

  5. SYNTHESIZING ORGANIC COMPOUNDS USING LIGHT-ACTIVATED TIO2

    EPA Science Inventory

    High-value organic compounds have been synthesized successfully from linear and cyclic hydrocarbons, by photocatalytic oxidation using a semiconductor material, titanium dioxide (TiO2). Various hydrocarbons were partially oxgenated in both liquid and gaseous phase reactors usi...

  6. Predicting the emission of volatile organic compounds from silage systems

    USDA-ARS?s Scientific Manuscript database

    As a precursor to smog, emission of volatile organic compounds (VOCs) to the atmosphere is an environmental concern in some regions. The major VOC emission source from farms is silage, with emissions coming from the silo face, mixing wagon, and feed bunk. The major compounds emitted are alcohols wit...

  7. Characteristics of organic compounds in PM2.5 at urban and remote areas in Korea

    NASA Astrophysics Data System (ADS)

    Choi, A.; Lee, J.; Shin, H. J.; Lee, M.; Jin seok, H.; Lim, J.

    2016-12-01

    Organic aerosols contain thousands of organic compounds and contribute to 20%-90% of the total fine aerosol mass (Kanakidou et al., 2005). These organic aerosols originate from anthropogenic and natural (biogenic and geologic) sources and alter physical and chemical properties in the atmosphere depending on the atmospheric and meteorological conditions. About one hundred individual organic compounds in PM2.5 at Seoul (urban area) and Baengnyeong Island (remote area) were identified and quantified using gas chromatography/mass spectrometry (GC/MS) in order to understand the characteristics of organic compounds in PM2.5 at these areas. Further, major factors to determine their concentrations in the atmosphere were investigated. Organic compounds analyzed in this study were classified into six groups, n-alkanes, polycyclic aromatic hydrocarbons (PAHs), hopanes, fatty acids (FA), dicarboxylic acids (DCAs), and sugars. Daily variation of organic compounds concentrations at Seoul were not high, while, the concentrations of organic compounds at Baengnyeong Island showed high daily variation. This is might due to frequent change of source strength and/or SOA formation in this region. Through correlations of organic compounds with other air pollutants and factor analysis at both sites, it found that major factors (or source) for the determination of organic compounds concentrations at Seoul and Baengnyeong Island were different. The major sources at Seoul were anthropogenic sources such as vehicular emission and coal combustions, while, SOA formation and biomass burning were more attributed more to the organic compounds concentrations at Baengnyeong Island.References Kanakidou, M., Seinfeld, J.H., Pandis, S.N., Barnes, I., Dentener, F.J., Facchini, M.C., Van Dingenen, R., Ervens, B., Nenes, A., Nielsen, C.J., Swietlicki, E., Putaud, J.P., Balkanski, Y., Fuzzi, S., Horth, J., Moortgat, G.K., Winterhalter, R., Myhre, C.E.L., Tsigaridis, K., Vignati, E., Stephanou, E

  8. Volatile Halogenated Organic Compounds Released to Seawater from Temperate Marine Macroalgae

    NASA Astrophysics Data System (ADS)

    Gschwend, Philip M.; Macfarlane, John K.; Newman, Kathleen A.

    1985-03-01

    Volatile halogenated organic compounds synthesized by various industrial processes are troublesome pollutants because they are persistent in terrestrial ecosystems and because they may be present in sufficient quantities to alter the natural atmospheric cycles of the halogens. Certain of these compounds, including polybromomethanes and several previously unobserved alkyl monohalides and dihalides, appear to be natural products of the marine environment. A variety of temperate marine macroalgae (the brown algae Ascophyllum nodosum and Fucus vesiculosis, the green algae Enteromorpha linza and Ulva lacta, and the red alga Gigartina stellata) not only contain volatile halogenated organic compounds but also release them to seawater at rates of nanograms to micrograms of each compound per gram of dry algae per day. The macroalgae may be an important source of bromine-containing material released to the atmosphere.

  9. End-group-directed self-assembly of organic compounds useful for photovoltaic applications

    DOEpatents

    Beaujuge, Pierre M.; Lee, Olivia P.; Yiu, Alan T.; Frechet, Jean M.J.

    2016-05-31

    The present invention provides for an organic compound comprising electron deficient unit covalently linked to two or more electron rich units. The present invention also provides for a device comprising the organic compound, such as a light-emitting diode, thin-film transistor, chemical biosensor, non-emissive electrochromic, memory device, photovoltaic cells, or the like.

  10. Detecting and Eliminating Interfering Organic Compounds in Waters Analyzed for Isotopic Composition by Crds

    NASA Astrophysics Data System (ADS)

    Richman, B. A.; Hsiao, G. S.; Rella, C.

    2010-12-01

    Optical spectroscopy based CRDS technology for isotopic analysis of δD and δ18O directly from liquid water has greatly increased the number and type of liquid samples analyzed. This increase has also revealed a previously unrecognized sample contamination problem. Recently West[1] and Brand[2] identified samples containing ethanol, methanol, plant extracts and other organic compounds analyzed by CRDS and other spectroscopy based techniques as yielding erroneous results for δD and δ18O (especially δD) due to spectroscopic interference. Not all organic compounds generate interference. Thus, identifying which samples are contaminated by which organic compounds is of key importance for data credibility and correction. To address this problem a new approach in the form of a software suite, ChemCorrect™, has been developed. A chemometrics component uses a spectral library of water isotopologues and interfering organic compounds to best fit the measured spectra. The best fit values provide a quantitative assay of the actual concentrations of the various species and are then evaluated to generate a visual flag indicating samples affected by organic contamination. Laboratory testing of samples spiked with known quantities of interfering organic compounds such as methanol, ethanol, and terpenes was performed. The software correctly flagged and identified type of contamination for all the spiked samples without any false positives. Furthermore the reported values were a linear function of actual concentration with an R^2>0.99 even for samples which contained multiple organic compounds. Further testing was carried out against a range of industrial chemical compounds which can contaminate ground water as well as a variety of plant derived waters and juices which were also analyzed by IRMS. The excellent results obtained give good insight into which organic compounds cause interference and which classes of plants are likely to contain interfering compounds. Finally

  11. Sorption interactions of organic compounds with soils affected by agricultural olive mill wastewater.

    PubMed

    Keren, Yonatan; Borisover, Mikhail; Bukhanovsky, Nadezhda

    2015-11-01

    The organic compound-soil interactions may be strongly influenced by changes in soil organic matter (OM) which affects the environmental fate of multiple organic pollutants. The soil OM changes may be caused by land disposal of various OM-containing wastes. One unique type of OM-rich waste is olive mill-related wastewater (OMW) characterized by high levels of OM, the presence of fatty aliphatics and polyphenolic aromatics. The systematic data on effects of the land-applied OMW on organic compound-soil interactions is lacking. Therefore, aqueous sorption of simazine and diuron, two herbicides, was examined in batch experiments onto three soils, including untreated and OMW-affected samples. Typically, the organic compound-soil interactions increased following the prior land application of OMW. This increase is associated with the changes in sorption mechanisms and cannot be attributed solely to the increase in soil organic carbon content. A novel observation is that the OMW application changes the soil-sorbent matrix in such a way that the solute uptake may become cooperative or the existing ability of a soil sorbent to cooperatively sorb organic molecules from water may become characterized by a larger affinity. The remarkable finding of this study was that in some cases a cooperative uptake of organic molecules by soils makes itself evident in distinct sigmoidal sorption isotherms rarely observed in soil sorption of non-ionized organic compounds; the cooperative herbicide-soil interactions may be characterized by the Hill model coefficients. However, no single trend was found for the effect of applied OMW on the mechanisms of organic compound-soil interactions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Simulation of Comet Impact and Survivability of Organic Compounds

    NASA Astrophysics Data System (ADS)

    Liu, Benjamin; Lomov, Ilya; Blank, Jennifer; Antoun, Tarabay

    2007-06-01

    Comets have been proposed as a mechanism for the transport of complex organic compounds to Earth. For this to occur, a significant fraction of organic compounds must survive the shock loading, in particular the high temperatures, due to impact. 2D and 3D numerical simulations were performed to study the thermodynamic states due to a comet impact. The comet was modeled as a 1-km diameter icy sphere traveling at the Earth's escape velocity (11 km/s) impacting a half-space of basalt. Simulations were performed with GEODYN, a parallel, multi-material, Godunov-based Eulerian code employing adaptive mesh refinement. A constitutive model calibrated for hard rock was used for basalt. Tabular equations of state were used to account for the extreme conditions present upon shock loading. A major focus of the study was tracking the thermodynamic state of the comet material. Both the maximum temperature experienced and the phase were tracked for each point in the comet Temperature histories in the comet were also recorded. These quantities were used to estimate viability of organic compounds upon impact. This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48.

  13. LOSS OF ORGANIC CHEMICALS IN SOIL: PURE COMPOUND TREATABILITY STUDIES

    EPA Science Inventory

    Comprehensive screening data on the treatability of 32 organic chemicals in soil were developed. Of the evaluated chemicals, 22 were phenolic compounds. Aerobic batch laboratory microcosm experiments were conducted using two soils: an acidic clay soil with <1% organic matter and ...

  14. FACTORS CONTROLLING THE EMISSIONS OF MONOTERPENES AND OTHER VOLATILE ORGANIC COMPOUNDS

    EPA Science Inventory

    Plants contain a number of volatile organic compounds, including isoprene, mono- and sesquiterpenes, alcohols, aldehydes, ketones, and esters. ndividual plant species have unique combinations of these compounds; consequently, the emission pattern for each species is also specific...

  15. Volatile organic compound sensor system

    DOEpatents

    Schabron, John F [Laramie, WY; Rovani, Jr., Joseph F.; Bomstad, Theresa M [Laramie, WY; Sorini-Wong, Susan S [Laramie, WY

    2009-02-10

    Generally, this invention relates to the development of field monitoring methodology for new substances and sensing chemical warfare agents (CWAs) and terrorist substances. It also relates to a portable test kit which may be utilized to measure concentrations of halogenated volatile organic compounds (VOCs) in the field. Specifically it relates to systems for reliably field sensing the potential presence of such items while also distinguishing them from other elements potentially present. It also relates to overall systems and processes for sensing, reacting, and responding to an indicated presence of such substance, including modifications of existing halogenated sensors and arrayed sensing systems and methods.

  16. Volatile organic compound sensor system

    DOEpatents

    Schabron, John F.; Rovani, Jr., Joseph F.; Bomstad, Theresa M.; Sorini-Wong, Susan S.; Wong, Gregory K.

    2011-03-01

    Generally, this invention relates to the development of field monitoring methodology for new substances and sensing chemical warfare agents (CWAs) and terrorist substances. It also relates to a portable test kit which may be utilized to measure concentrations of halogenated volatile organic compounds (VOCs) in the field. Specifically it relates to systems for reliably field sensing the potential presence of such items while also distinguishing them from other elements potentially present. It also relates to overall systems and processes for sensing, reacting, and responding to an indicated presence of such substance, including modifications of existing halogenated sensors and arrayed sensing systems and methods.

  17. N-doping of organic semiconductors by bis-metallosandwich compounds

    DOEpatents

    Barlow, Stephen; Qi, Yabing; Kahn, Antoine; Marder, Seth; Kim, Sang Bok; Mohapatra, Swagat K.; Guo, Song

    2016-01-05

    The various inventions disclosed, described, and/or claimed herein relate to the field of methods for n-doping organic semiconductors with certain bis-metallosandwich compounds, the doped compositions produced, and the uses of the doped compositions in organic electronic devices. Metals can be manganese, rhenium, iron, ruthenium, osmium, rhodium, or iridium. Stable and efficient doping can be achieved.

  18. Identification and quantification of volatile organic compounds using systematic single-ion chromatograms

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsuchiya, Yoshio; Kanabus-Kaminska, J.M.

    1996-12-31

    In order to determine the background level of volatile organic compounds (VOCs) in Canadian indoor air, a method of identification and quantification at a level of 0.3 {micro}g/m{sup 3} using systematic single-ion chromatograms (SICs) has been developed. The compounds selected for measurement included several halogenated compounds, oxygen compounds, terpenes, and C8 to C16 n-alkanes. Air samples were taken in 3-layered sorbent tubes and trapped compounds were thermally desorbed into the helium stream of a gas chromatograph/mass spectrometer (GC/MS) analytical system. Total quantities of volatile organic compounds (TVOCs) were measured using a flame ionization detector (FID). Individual compounds were analyzed bymore » a GC/MS. For the identification of compounds in the main stream GC effluent, both the specific GC retention and mass spectra were used. About 50 selected SICs were routinely extracted from a total ion chromatogram (TIC) to detect and quantify compounds. For each compound, a single representative ion was selected. The specific retention was calculated from the elution time on the SIC. For quantification, ion counts under a peak in the SIC were measured. The single-ion MS response factor for some of the compounds was experimentally determined using a dynamic reference procedure.« less

  19. Volatile and semivolatile organic compounds in laboratory peat fire emissions

    EPA Science Inventory

    Speciated volatile organic compounds (VOCs) and organic fine particulate matter (PM2.5) mass emission factors were determined from laboratory peat fire experiments. Peat samples originated from two wildlife reserves located near the coast of North Carolina, U.S. Gas and particula...

  20. Sugar-Related Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Cooper, G.; Kimmich, N.; Belisle, W.; Sarinana, J.; Brabham, K.; Garrel, L.; DeVincenzi, Donald L. (Technical Monitor)

    2001-01-01

    Sugars and related polyols are critical components of all organisms and may have been necessary for the origin of life. To date, this class of organic compounds had not been definitively identified in meteorites. This study was undertaken to determine if polyols were present in the early Solar System as constituents of carbonaceous meteorites. Results of analyses of the Murchison and Murray meteorites indicate that formaldehyde and sugar chemistry may be responsible for the presence of a variety of polyols. We conclude that polyols were present on the early Earth through delivery by asteroids and possibly comets.

  1. Compound prioritization methods increase rates of chemical probe discovery in model organisms

    PubMed Central

    Wallace, Iain M; Urbanus, Malene L; Luciani, Genna M; Burns, Andrew R; Han, Mitchell KL; Wang, Hao; Arora, Kriti; Heisler, Lawrence E; Proctor, Michael; St. Onge, Robert P; Roemer, Terry; Roy, Peter J; Cummins, Carolyn L; Bader, Gary D; Nislow, Corey; Giaever, Guri

    2011-01-01

    SUMMARY Pre-selection of compounds that are more likely to induce a phenotype can increase the efficiency and reduce the costs for model organism screening. To identify such molecules, we screened ~81,000 compounds in S. cerevisiae and identified ~7,500 that inhibit cell growth. Screening these growth-inhibitory molecules across a diverse panel of model organisms resulted in an increased phenotypic hit-rate. This data was used to build a model to predict compounds that inhibit yeast growth. Empirical and in silico application of the model enriched the discovery of bioactive compounds in diverse model organisms. To demonstrate the potential of these molecules as lead chemical probes we used chemogenomic profiling in yeast and identified specific inhibitors of lanosterol synthase and of stearoyl-CoA 9-desaturase. As community resources, the ~7,500 growth-inhibitory molecules has been made commercially available and the computational model and filter used are provided. PMID:22035796

  2. Investigation of sorption interactions between oil shale principal mineral phases and organic compounds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bowen, J.M.

    1988-09-01

    The interactions between minerals representative of the bulk composition of oil shales and organic compounds that have been found in oil shale leachates were investigated. The method used to directly determine the type of interactions that could take place between organic compounds and oil shale mineral phases was Fourier transform infrared spectroscopy (FTIR) using several advanced detection methods, including diffuse reflectance (DRIFT) and photoacoustics (PAS). The minerals that were investigated include quartz, calcite, and dolomite, which are known to figure significantly in the composition of processed oil shales. The organic chemical compounds used were chosen from a list of compoundsmore » identified in spent oil shale leachates, and they include pyridine, phenol, p-cresol, and acetone. The sorption interactions for the study were prepared by exposing each of the minerals to the organic compounds by three different methods. These were vapor deposition, direct application, and immersion in an aqueous solution at pH 12. 41 refs., 3 figs., 4 tabs.« less

  3. Removal of bulk dissolved organic carbon (DOC) and trace organic compounds by bank filtration and artificial recharge.

    PubMed

    Grünheid, Steffen; Amy, Gary; Jekel, Martin

    2005-09-01

    Bank filtration and artificial recharge provide an important drinking water source to the city of Berlin. Due to the practice of water recycling through a semi-closed urban water cycle, the introduction of effluent organic matter (EfOM) and persistent trace organic pollutants in the drinking water is of potential concern. In the work reported herein, the research objectives are to study the removal of bulk and trace organics at bank filtration and artificial recharge sites and to assess important factors of influence for the Berlin area. The monthly analytical program is comprised of dissolved organic carbon (DOC), UV absorbance (UVA254), liquid chromatography with organic carbon detection (LC-OCD), differentiated adsorbable organic halogens (AOX) and single organic compound analysis of a few model compounds. More than 1 year of monitoring was conducted on observation wells located along the flowpaths of the infiltrating water at two field sites that have different characteristics regarding redox conditions, travel time, and travel distance. Two transects are highlighted: one associated with a bank filtration site dominated by anoxic/anaerobic conditions with a travel time of up to 4-5 months, and another with an artificial recharge site dominated by aerobic conditions with a travel time of up to 50 days. It was found that redox conditions and travel time significantly influence the DOC degradation kinetics and the efficiency of AOX and trace compound removal.

  4. Manmade organic compounds in the surface waters of the United States: a review of current understanding

    USGS Publications Warehouse

    Smith, James A.; Witkowski, Patrick J.; Fusillo, Thomas V.

    1987-01-01

    This report reviews the occurrence and distribution of manmade organic compounds in the surface waters of the United States. On the basis of their aqueous solubilities, nonionic organic compounds partition themselves between water, dissolved organic matter, particulate organic matter, and the lipid reservoirs of aquatic organisms. Ionized organic compounds can be absorbed to sediments, thereby reducing their aqueous concentrations. Transformation processes of photolysis, hydrolysis, biodegradation, and volatilization can attenuate organic compounds, and attenuation rate commonly follow a first-order kinetic process. Eight groups of manmade organic compounds are discussed: 1. Polychlorinated biphenyls and organochlorine insecticides, 2. Carbamate and organophosphorus insecticides, 3. Herbicides, 4. Phenols, 5. Halogenated aliphatic and monocyclic aromatic hydrocarbons, 6. Phthalate esters, 7. Polychlorinated dibenzo-p-dioxins, and 8. Polycyclic aromatic hydrocarbons. For each compound group, data pertaining to use, production, and properties are presented and discussed. Processes that influence that the environmental fate of each group, as determined primarily through laboratory studies, are reviewed, and important fate processes are identified. Environmental concentrations of compounds from each group in water, biota, and sediment are given to demonstrate representative values for comparison to concentrations determined during ongoing research. Finally, where sufficient data exist, regional and temporal contamination trends in the United States are discussed.

  5. Manmade organic compounds in the surface waters of the United States; a review of current understanding

    USGS Publications Warehouse

    Smith, James A.; Witkowski, P.J.; Fusillo, Thomas V.

    1988-01-01

    This report reviews the occurrence and distribution of manmade organic compounds in the surface waters of the United States. On the basis of their aqueous solubilities, nonionic organic compounds partition themselves among water, dissolved organic matter, particulate organic matter, and the lipid reservoirs of aquatic organisms. Ionized organic compounds can be adsorbed to sediments, thereby reducing their aqueous concentrations. Transformation processes of photolysis, hydrolysis, biodegradation, and volatilization can attenuate organic compounds, and attenuation rates commonly follow a first-order kinetic process. Eight groups of manmade organic compounds are discussed: 1. Polychlorinated biphenyls and organochlorine insecticides, 2. Carbamate and organophosphorus insecticides, 3. Herbicides, 4. Phenols, 5. Halogenated aliphatic and monocyclic aromatic hydrocarbons, 6. Phthalate esters, 7. Polychlorinated dibenzo-p-dioxins, and 8. Polycyclic aromatic hydrocarbons. For each compound group, data pertaining to use, production, and properties are presented and discussed. Processes that influence the environmental fate of each group, as determined primarily through laboratory studies, are reviewed, and important fate processes are identified. Environmental concentrations of compounds from each group in water, biota, and sediment are given to demonstrate representative values for comparison with concentrations determined during ongoing research. Finally, where data are sufficient, regional and temporal contamination trends in the United States are discussed.

  6. Analysis of selected volatile organic compounds at background level in South Africa.

    NASA Astrophysics Data System (ADS)

    Ntsasa, Napo; Tshilongo, James; Lekoto, Goitsemang

    2017-04-01

    Volatile organic compounds (VOC) are measured globally at urban air pollution monitoring and background level at specific locations such as the Cape Point station. The urban pollution monitoring is legislated at government level; however, the background levels are scientific outputs of the World Meteorological Organisation Global Atmospheric Watch program (WMO/GAW). The Cape Point is a key station in the Southern Hemisphere which monitors greenhouse gases and halocarbons, with reported for over the past decade. The Cape Point station does not have the measurement capability VOC's currently. A joint research between the Cape Point station and the National Metrology Institute of South Africa (NMISA) objective is to perform qualitative and quantitative analysis of volatile organic compounds listed in the GAW program. NMISA is responsible for development, maintain and disseminate primary reference gas mixtures which are directly traceable to the International System of Units (SI) The results of some volatile organic compounds which where sampled in high pressure gas cylinders will be presented. The analysis of samples was performed on the gas chromatography with flame ionisation detector and mass selective detector (GC-FID/MSD) with a dedicate cryogenic pre-concentrator system. Keywords: volatile organic compounds, gas chromatography, pre-concentrator

  7. Catalytic oxidation of volatile organic compounds (VOCs) - A review

    NASA Astrophysics Data System (ADS)

    Kamal, Muhammad Shahzad; Razzak, Shaikh A.; Hossain, Mohammad M.

    2016-09-01

    Emission of volatile organic compounds (VOCs) is one of the major contributors to air pollution. The main sources of VOCs are petroleum refineries, fuel combustions, chemical industries, decomposition in the biosphere and biomass, pharmaceutical plants, automobile industries, textile manufacturers, solvents processes, cleaning products, printing presses, insulating materials, office supplies, printers etc. The most common VOCs are halogenated compounds, aldehydes, alcohols, ketones, aromatic compounds, and ethers. High concentrations of these VOCs can cause irritations, nausea, dizziness, and headaches. Some VOCs are also carcinogenic for both humans and animals. Therefore, it is crucial to minimize the emission of VOCs. Among the available technologies, the catalytic oxidation of VOCs is the most popular because of its versatility of handling a range of organic emissions under mild operating conditions. Due to that fact, there are numerous research initiatives focused on developing advanced technologies for the catalytic destruction of VOCs. This review discusses recent developments in catalytic systems for the destruction of VOCs. Review also describes various VOCs and their sources of emission, mechanisms of catalytic destruction, the causes of catalyst deactivation, and catalyst regeneration methods.

  8. Use of beer bran as an adsorbent for the removal of organic compounds from wastewater.

    PubMed

    Adachi, Atsuko; Ozaki, Hiroaki; Kasuga, Ikuno; Okano, Toshio

    2006-08-23

    Beer bran was found to effectively adsorb several organic compounds, such as dichloromethane, chloroform, trichloroethylene, benzene, pretilachlor, and esprocarb. Equilibrium adsorption isotherms conformed to the Freundlich isotherm (log-log linear). Adsorption of these organic compounds by beer bran was observed in the pH range of 1-11. At equilibrium, the adsorption efficiency of beer bran for benzene, chloroform, and dichiloromethane was higher than that of activated carbon. The removal of these organic compounds by beer bran was attributed to the uptake by intracellular particles called spherosomes. The object of this work was to investigate several adsorbents for the effective removal of organic compounds from wastewater.

  9. Fatty acids and small organic compounds bind to mineralo-organic nanoparticles derived from human body fluids as revealed by metabolomic analysis

    NASA Astrophysics Data System (ADS)

    Martel, Jan; Wu, Cheng-Yeu; Hung, Cheng-Yu; Wong, Tsui-Yin; Cheng, Ann-Joy; Cheng, Mei-Ling; Shiao, Ming-Shi; Young, John D.

    2016-03-01

    Nanoparticles entering the human body instantly become coated with a ``protein corona'' that influences the effects and distribution of the particles in vivo. Yet, whether nanoparticles may bind to other organic compounds remains unclear. Here we use an untargeted metabolomic approach based on ultra-performance liquid chromatography and quadruple time-of-flight mass spectrometry to identify the organic compounds that bind to mineral nanoparticles formed in human body fluids (serum, plasma, saliva, and urine). A wide range of organic compounds is identified, including fatty acids, glycerophospholipids, amino acids, sugars, and amides. Our results reveal that, in addition to the proteins identified previously, nanoparticles harbor an ``organic corona'' containing several fatty acids which may affect particle-cell interactions in vivo. This study provides a platform to study the organic corona of biological and synthetic nanoparticles found in the human body.Nanoparticles entering the human body instantly become coated with a ``protein corona'' that influences the effects and distribution of the particles in vivo. Yet, whether nanoparticles may bind to other organic compounds remains unclear. Here we use an untargeted metabolomic approach based on ultra-performance liquid chromatography and quadruple time-of-flight mass spectrometry to identify the organic compounds that bind to mineral nanoparticles formed in human body fluids (serum, plasma, saliva, and urine). A wide range of organic compounds is identified, including fatty acids, glycerophospholipids, amino acids, sugars, and amides. Our results reveal that, in addition to the proteins identified previously, nanoparticles harbor an ``organic corona'' containing several fatty acids which may affect particle-cell interactions in vivo. This study provides a platform to study the organic corona of biological and synthetic nanoparticles found in the human body. Electronic supplementary information (ESI) available. See

  10. [Research on source profile of aerosol organic compounds in leather plant].

    PubMed

    Wang, Bo-Guang; Zhou, Yan; Feng, Zhi-Cheng; Liu, Hui-Xuan

    2009-04-15

    Through investigating current air pollution condition for PM10 in every factories of different style leather plants in Pearl River Delta, characteristic profile of semi-volatile organic compounds in PM10 emitted from leather factories and their contents were researched by using ultrasonic and gas chromatography and mass spectrum technology. The 6 types of organic compounds containing 46 species in total were found in the collected samples, including phenyl compounds, alcohols, PAHs, acids, esters and amides. The concentrations of PM10 in leather tanning plant, leather dying plant and man-made leather plant were 678.5, 454.5, 498.6 microgm x m(-3) respectively, and concentration of organic compounds in PM10 were 10.04, 6.89, 14.21 microg x m(-3) in sequence. The more important type of pollutants in each leather plants had higher contribution to total organic mass as follows, esters and amides in tanning plants profile account for 43.47% and 36.51% respectively; esters and alcohols in dying plants profiles account for 52.52% and 16.16% respectively; esters and amide in man-made leather plant have the highest content and account for 57.07% and 24.17% respectively. In the aerosol organic source profiles of tested leather plants, 9-octadecenamide was the abundant important species with the weight of 26.15% in tanning plant, and Bis(2-ethylhexyl) phthalate was up to 44.19% in the dying plant, and Bis(2-ethylhexyl) maleate and 1-hydroxy-piperidine had obviously higher weight in man-made plant than the other two plants.

  11. 40 CFR 60.712 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Magnetic Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or operator... (other than a condenser) on a magnetic tape coating operation shall control emissions from the coating...

  12. 40 CFR 60.712 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Magnetic Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or operator... (other than a condenser) on a magnetic tape coating operation shall control emissions from the coating...

  13. Organic compounds in water extracts of coal: links to Balkan endemic nephropathy.

    PubMed

    Maharaj, S V M; Orem, W H; Tatu, C A; Lerch, H E; Szilagyi, D N

    2014-02-01

    The Pliocene lignite hypothesis is an environmental hypothesis that has been proposed to explain the etiology of Balkan endemic nephropathy (BEN). Aqueous leaching experiments were conducted on a variety of coal samples in order to simulate groundwater leaching of organic compounds, and to further test the role of the Pliocene lignite hypothesis in the etiology of BEN. Experiments were performed on lignite coal samples from endemic BEN areas in Romania and Serbia, and lignite and bituminous coals from nonendemic regions in Romania and the USA. Room temperature, hot water bath, and Soxhlet aqueous extraction experiments were conducted between 25 and 80 °C, and from 5 to 128 days in duration. A greater number of organic compounds and in higher concentrations were present in all three types of leaching experiments involving endemic area Pliocene lignite samples compared to all other coals examined. A BEN causing molecule or molecules may be among phenols, PAHs, benzenes, and/or lignin degradation compounds. The proposed transport pathway of the Pliocene lignite hypothesis for organic compound exposure from endemic area Pliocene lignite coals to well and spring drinking water, is likely. Aromatic compounds leached by groundwater from Pliocene lignite deposits in the vicinity of endemic BEN areas may play a role in the etiology of the disease. A better understanding of organic compounds leached by groundwater from Pliocene lignite deposits may potentially lead to the identification and implementation of effective strategies for the prevention of exposure to the causative agent(s) for BEN, and in turn, prevention of the disease.

  14. Organic Compounds Complexify Transport in the Amargosa Desert—The Case for Phytotritiation

    NASA Astrophysics Data System (ADS)

    Stonestrom, D. A.; Luo, W.; Andraski, B. J.; Baker, R. J.; Maples, S.; Mayers, C. J.; Young, M. B.

    2014-12-01

    Civilian low-level radioactive waste containing organic compounds was disposed in 2- to 15-m deep unlined trenches in a 110-m deep unsaturated zone at the present-day USGS Amargosa Desert Research Site. Tritium represents the plurality of disposed activity. A plume of gas-phase contaminants surrounds the disposal area, with 60 distinct volatile organic compounds (VOCs) identified to date. The distribution of tritiated water in the unsaturated zone surrounding the disposal area is highly enigmatic, with orders of magnitude separating observed levels from those predicted by multiphase models of mass and energy transport. Peaks of tritium and VOCs are coincidently located in sediments tens of meters below the root zone, suggesting abiotic stratigraphic control on lateral transport at depth. Surprisingly, the highest observed levels of tritium occur at a depth of about 1.5 m, the base of the creosote-bush plant-community root zone, where levels of waste-derived VOCs are low (approaching atmospheric levels). Bulk water-vapor samples from shallow and deep unsaturated-zone profile hot spots were trapped as water ice in cold fingers immersed in dry ice-isopropyl alcohol filled Dewar flasks, then melted and sequentially extracted by purge-and-trap VOC degassing followed by elution through activated carbon solid-phase extraction (SPE) cartridges. Analysis of tritium activities and mass spectrometer results indicate that over 98% of tritium activity at depth is present as water, whereas about 15% of basal root zone tritium activity is present as organic compounds trapped with the water. Of these, the less-volatile compound group removed by SPE accounted for about 85% of the organic tritium activity, with mass spectrometry identifying 2-ethyl-1-hexanol as the principal compound removed. This plant-produced fatty alcohol is ubiquitous in the root zone of creosote-bush communities and represents a family of hydroxyl-containing plant produced compounds that give the plants their

  15. Tetratopic phenyl compounds, related metal-organic framework materials and post-assembly elaboration

    DOEpatents

    Farha, Omar K.; Hupp, Joseph T.

    2012-09-11

    Disclosed are tetratopic carboxylic acid phenyl for use in metal-organic framework compounds. These compounds are useful in catalysis, gas storage, sensing, biological imaging, drug delivery and gas adsorption separation.

  16. Tetratopic phenyl compounds, related metal-organic framework materials and post-assembly elaboration

    DOEpatents

    Farha, Omar K; Hupp, Joseph T

    2013-06-25

    Disclosed are tetratopic carboxylic acid phenyl for use in metal-organic framework compounds. These compounds are useful in catalysis, gas storage, sensing, biological imaging, drug delivery and gas adsorption separation.

  17. Students' Understanding of Molecular Structure and Properties of Organic Compounds.

    ERIC Educational Resources Information Center

    Schmidt, Hans-Jurgen

    The purpose of this study was to investigate senior high school students' difficulties predicting the existence of hydrogen bridge bonds between organic molecules, investigate students' difficulties predicting the relative boiling points of simple organic compounds, and develop test questions that enable teachers to quickly get information about…

  18. Spatial arrangement of organic compounds on a model mineral surface: implications for soil organic matter stabilization.

    PubMed

    Petridis, Loukas; Ambaye, Haile; Jagadamma, Sindhu; Kilbey, S Michael; Lokitz, Bradley S; Lauter, Valeria; Mayes, Melanie A

    2014-01-01

    The complexity of the mineral-organic carbon interface may influence the extent of stabilization of organic carbon compounds in soils, which is important for global climate futures. The nanoscale structure of a model interface was examined here by depositing films of organic carbon compounds of contrasting chemical character, hydrophilic glucose and amphiphilic stearic acid, onto a soil mineral analogue (Al2O3). Neutron reflectometry, a technique which provides depth-sensitive insight into the organization of the thin films, indicates that glucose molecules reside in a layer between Al2O3 and stearic acid, a result that was verified by water contact angle measurements. Molecular dynamics simulations reveal the thermodynamic driving force behind glucose partitioning on the mineral interface: The entropic penalty of confining the less mobile glucose on the mineral surface is lower than for stearic acid. The fundamental information obtained here helps rationalize how complex arrangements of organic carbon on soil mineral surfaces may arise.

  19. Clean process to destroy arsenic-containing organic compounds with recovery of arsenic

    DOEpatents

    Upadhye, R.S.; Wang, F.T.

    1996-08-13

    A reduction method is provided for the treatment of arsenic-containing organic compounds with simultaneous recovery of pure arsenic. Arsenic-containing organic compounds include pesticides, herbicides, and chemical warfare agents such as Lewisite. The arsenic-containing compound is decomposed using a reducing agent. Arsine gas may be formed directly by using a hydrogen-rich reducing agent, or a metal arsenide may be formed using a pure metal reducing agent. In the latter case, the arsenide is reacted with an acid to form arsine gas. In either case, the arsine gas is then reduced to elemental arsenic. 1 fig.

  20. Clean process to destroy arsenic-containing organic compounds with recovery of arsenic

    DOEpatents

    Upadhye, Ravindra S.; Wang, Francis T.

    1996-01-01

    A reduction method is provided for the treatment of arsenic-containing organic compounds with simultaneous recovery of pure arsenic. Arsenic-containing organic compounds include pesticides, herbicides, and chemical warfare agents such as Lewisite. The arsenic-containing compound is decomposed using a reducing agent. Arsine gas may be formed directly by using a hydrogen-rich reducing agent, or a metal arsenide may be formed using a pure metal reducing agent. In the latter case, the arsenide is reacted with an acid to form arsine gas. In either case, the arsine gas is then reduced to elemental arsenic.

  1. A microfluidic device for open loop stripping of volatile organic compounds.

    PubMed

    Cvetković, Benjamin Z; Dittrich, Petra S

    2013-03-01

    The detection of volatile organic compounds is of great importance for assessing the quality of water. In this contribution, we describe a miniaturized stripping device that allows fast online detection of organic solvents in water. The core component is a glass microfluidic chip that facilitates the creation of an annular-flowing stream of water and nitrogen gas. Volatile compounds are transferred efficiently from the water into the gas phase along the microfluidic pathway at room temperature within less than 5 s. Before exiting the microchip, the liquid phase is separated from the enriched gas phase by incorporating side capillaries through which the hydrophilic water phase is withdrawn. The gas phase is conveniently collected at the outlet reservoir by tubing. Finally, a semiconductor gas sensor analyzes the concentration of (volatile) organic compounds in the nitrogen gas. The operation and use of the stripping device is demonstrated for the organic solvents THF, 1-propanol, toluene, ethylbenzene, benzaldehyde, and methanol. The mobile, inexpensive, and continuously operating system with liquid flow rates in the low range of microliters per minute can be connected to other detectors or implemented in chemical production line for process control.

  2. Organic compounds downstream from a treated-wastewater discharge near Dallas, Texas, March 1987

    USGS Publications Warehouse

    Buszka, P.M.; Barber, L.B.; Schroeder, M.P.; Becker, L.D.

    1994-01-01

    Comparison of instantaneous flux values of selected organic compounds in water from downstream sites indicates: (1) the formation of chloroform in the stream following the discharge of the treated effluent, and that (2) instream biodegradation may be decreasing concentrations of linear alkylbenzene compounds in water. The relative persistence of many of the selected organic compounds in Rowlett Creek downstream from the municipal wastewater-treatment plant indicates that they could be transported into Lake Ray Hubbard, a source of municipal water supply.

  3. Azo compounds as a family of organic electrode materials for alkali-ion batteries.

    PubMed

    Luo, Chao; Borodin, Oleg; Ji, Xiao; Hou, Singyuk; Gaskell, Karen J; Fan, Xiulin; Chen, Ji; Deng, Tao; Wang, Ruixing; Jiang, Jianjun; Wang, Chunsheng

    2018-02-27

    Organic compounds are desirable for sustainable Li-ion batteries (LIBs), but the poor cycle stability and low power density limit their large-scale application. Here we report a family of organic compounds containing azo group (N=N) for reversible lithiation/delithiation. Azobenzene-4,4'-dicarboxylic acid lithium salt (ADALS) with an azo group in the center of the conjugated structure is used as a model azo compound to investigate the electrochemical behaviors and reaction mechanism of azo compounds. In LIBs, ADALS can provide a capacity of 190 mAh g -1 at 0.5 C (corresponding to current density of 95 mA g -1 ) and still retain 90%, 71%, and 56% of the capacity when the current density is increased to 2 C, 10 C, and 20 C, respectively. Moreover, ADALS retains 89% of initial capacity after 5,000 cycles at 20 C with a slow capacity decay rate of 0.0023% per cycle, representing one of the best performances in all organic compounds. Superior electrochemical behavior of ADALS is also observed in Na-ion batteries, demonstrating that azo compounds are universal electrode materials for alkali-ion batteries. The highly reversible redox chemistry of azo compounds to alkali ions was confirmed by density-functional theory (DFT) calculations. It provides opportunities for developing sustainable batteries.

  4. The study of volatile organic compounds in urban and indoor air

    NASA Astrophysics Data System (ADS)

    Clarkson, Paul Jonathan

    Chapter 1 is a review of the literature concerning the study of volatile organic compounds in the atmosphere. It examines the basic chemistry of the atmosphere and the roles that organic compounds play in it. Also investigated are the methods of sampling and analysing the volatile organic compounds in the air, paying particular attention to the role of solid phase sampling. Chapter 1 also examines the role of volatile organic compounds on air quality. Chapter 2 describes the experimental procedures that were employed during the course of this research project. Chapter 3 examines a multi-method approach to the study of volatile organic compounds in urban and indoor air. The methods employed were capillary electrophoresis, high performance liquid chromatography and gas chromatography. Although good results were obtained for the various methods that were investigated Chapter 3 concludes that a more unified analytical approach is needed to the study of the air. Chapter 4 investigates the possibilities of using a unified approach to the study of VOC's. This is achieved by the development of an air sampling method that uses solid phase extraction cartridges. By investigating many aspects of air sampling mechanisms the results show that a simple yet efficient method for the sampling of VOC in air has been developed. The SPE method is a reusable, yet reliable method that by using sequential solvent desorption has been shown to exhibit some degree of selectivity. The solid phase that gave the best results was styrene-divinyl benzene however other phases were also investigated. The use of a single gas chromatography method was also investigated for the purpose of confirmatory identification of the VOC's. Various detection systems were used including MS and AED. It was shown that by optimising the GC's it was possible to get complimentary results. Also investigated was the possibility of compound tagging in an attempt to confirm the identity of several of the compounds found

  5. Seasonal Variations of Quantified Organic Compounds in PM10 over Seoul

    NASA Astrophysics Data System (ADS)

    Choi, N.; Lee, J.; Kim, Y. P.

    2014-12-01

    The concentrations of 87 individual organic matters in the PM10 samples, systematically collected on the roof of the School of Public Health building at Seoul National University (mixed commercial and residential area), Seoul, South Korea on a daily basis from April 2010 to April 2011, were quantified by mean of Gas Chromatography/Mass Spectrometry (GC/MS). The daily average concentrations of five organic groups, alkanes, PAHs, fatty acid, DCAs, and sugars were ranged from 498.40 ng m3 to 10.20 μg m3. The seasonal concentrations of the total quantified organic species were 1.73 μg m3 (Spring), 2.04 μg m3 (Summer), 3.11 μg m3 (Fall), and 3.60 μg m3 (Winter), respectively. All the organic groups showed higher average concentration in winter than in summer. However, some organic compounds among fatty acids, DCAs, and sugars showed reverse pattern. The seasonal concentration patterns and episode variation of individual organic compounds were studied to clarify the emission characteristics of organic matters in PM10.

  6. Sorption of vapors of some organic liquids on soil humic acid and its relation to partitioning of organic compounds in soil organic matter

    USGS Publications Warehouse

    Chlou, G.T.; Kile, D.E.; Malcolm, R.L.

    1988-01-01

    Vapor sorption of water, ethanol, benzene, hexane, carbon tetrachloride, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethylene, and 1,2-dibromoethane on (Sanhedron) soil humic acid has been determined at room temperature. Isotherms for all organic liquids are highly linear over a wide range of relative pressure (P/P??), characteristic of the partitioning (dissolution) of the organic compounds in soil humic acid. Polar liquids exhibit markedly greater sorption capacities on soil humic acid than relatively nonpolar liquids, in keeping with the polar nature of the soil humic acid as a partition medium. The limiting sorption (partition) capacities of relatively non-polar liquids are remarkably similar when expressed in terms of volumes per unit weight of soil humic acid. The soil humic acid is found to be about half as effective as soil organic matter in sorption of relatively nonpolar organic compounds. The nearly constant limiting sorption capacity for nonpolar organic liquids with soil humic acid on a volume-to-weight basis and its efficiency in sorption relative to soil organic matter provide a basis for predicting the approximate sorption (partition) coefficients of similar compounds in uptake by soil in aqueous systems.

  7. ESTIMATION OF PHYSIOCHEMICAL PROPERTIES OF ORGANIC COMPOUNDS BY SPARC

    EPA Science Inventory

    The computer program SPARC (SPARC Performs Automated Reasoning in Chemistry) has been under development for several years to estimate physical properties and chemical reactivity parameters of organic compounds strictly from molecular structure. SPARC uses computational algorithms...

  8. Emission of volatile organic compounds (VOCs) from PVC floor coverings.

    PubMed

    Wiglusz, R; Igielska, B; Sitko, E; Nikel, G; Jarnuszkiewicz, I

    1998-01-01

    In this study 29 PVC floor coverings were tested for emission of vinyl chloride (VC) and other volatile organic compounds (VOCs). A study on the effect of higher temperature on emission of VOCs from newly manufactured PVC flooring was also carried out. The study was conducted in climatic chamber, according to Polish Standard PN-89/Z-04021. GC method was used for analyzing of the compounds emitted. VC was not emitted from any of the floorings tested. Other VOCs were emitted in different concentrations. The influence of temperature on emission was conducted at temperatures of 23 degrees C and 35 degrees C from 2 hrs up to 180 days after introduction of materials in the chamber. The increase of temperature caused increase of total volatile organic compounds (TVOC) emission during 24 hrs of experiment. Then the emission was comparable for both temperatures. After 9 days emission of identified and unidentified compounds (TVOC) showed a rapid decay and stayed on very low level during a few months. The study conducted showed that PVC floorings after 10 days of installation in the room should not be source of indoor air contamination.

  9. Measurement of volatile organic compounds in human blood.

    PubMed Central

    Ashley, D L; Bonin, M A; Cardinali, F L; McCraw, J M; Wooten, J V

    1996-01-01

    Volatile organic compounds (VOCs) are an important public health problem throughout the developed world. Many important questions remain to be addressed in assessing exposure to these compounds. Because they are ubiquitous and highly volatile, special techniques must be applied in the analytical determination of VOCs. The analytical methodology chosen to measure toxicants in biological materials must be well validated and carefully carried out; poor quality assurance can lead to invalid results that can have a direct bearing on treating exposed persons. The pharmacokinetics of VOCs show that most of the internal dose of these compounds is quickly eliminated, but there is a fraction that is only slowly removed, and these compounds may bioaccumulate. VOCs are found in the general population at the high parts-per-trillion range, but some people with much higher levels have apparently been exposed to VOC sources away from the workplace. Smoking is the most significant confounder to internal dose levels of VOCs and must be considered when evaluating suspected cases of exposure. PMID:8933028

  10. Laboratory Studies of Organic Compounds With Reflectance Spectroscopy

    NASA Astrophysics Data System (ADS)

    Curchin, J. M.; Clark, R. N.; Hoefen, T. M.

    2007-12-01

    In order to properly interpret reflectance spectra of any solar system surface from the earth to the Oort cloud, laboratory spectra of candidate materials for comparative analysis are needed. Although the common cosmochemical species (H2O, CO2, CO, NH3, and CH4) are well represented in the spectroscopic literature, comparatively little reflectance work has been done on organics from room to cryogenic temperatures at visible to near infrared wavelengths. Reflectance spectra not only enhance weak or unseen transmission features, they are also more analogous to spectra obtained by spacecraft that are imaging such bodies as giant planet moons, kuiper belt objects, centaurs, comets and asteroids, as well as remote sensing of the earth. The USGS Spectroscopy Laboratory is measuring reflectance spectra of organic compounds from room to cryogenic temperatures over the spectral range of 0.35 to 15.5 microns. This region encompasses the fundamental absorptions and many overtones and combinations of C, H, O, and N molecular bonds. Because most organic compounds belong to families whose members have similar structure and composition, individual species identification within a narrow wavelength range may be ambiguous. By measuring spectral reflectance of the pure laboratory samples from the visible through the near and mid-infrared, absorption bands unique to each can be observed, cataloged, and compared to planetary reflectance data. We present here spectra of organic compounds belonging to five families: the alkanes, alkenes, alkynes, aromatics, and cyanides. Common to all of these are the deep C-H stretch fundamental absorptions, which shift shortward from 3.35+ microns in alkanes to 3.25+ microns in aromatics, to 3.2+ microns in alkenes, and down to 3.0+ microns in alkynes. Mid-IR absorptions due to C-H bending deformations at 6.8+ and 7.2+ microns are also identified. In the near infrared these stretching and bending fundamentals yield a diagnostic set of combination

  11. Organic compounds and trace elements in the Pocomoke River and its tributaries

    USGS Publications Warehouse

    Miller, Cherie V.; Foster, Gregory D.; Huff, Thomas B.; Garbarino, John R.

    1999-01-01

    In response to concern about recent blooms of the dinoflagellate, Pfiesteria piscicida, samples of sediment and water were collected from the lower Pocomoke River Basin and were screened for trace elements, pesticides, and other organic compounds. A large group of steroid and fatty acid methyl-ester compounds was detected in streamwater using gas chromatography/mass spectroscopy in scan mode. Some of these steroid compounds have been identified and further quantified in bed-sediment extracts. Spatial patterns of the concentrations of cholesterol suggest that these compounds are linked to the runoff of animal wastes into the river. Many of the organic compounds found in the Pocomoke River sediments have not yet been identified, but at least several are in the class of hormone compounds related to estradiols and have the potential to promote endocrine-disrupting effects in aquatic life. Particulate forms of arsenic and zinc are slightly elevated above normal levels for streams, but the sources for these elements are still undetermined. Several pesticides were found in low, parts-per-trillion concentrations, but were within the ranges commonly found in streams of this region.

  12. [Bibliographical study of the toxicity of organic mercury compounds].

    PubMed

    Ishihara, Nobuo

    2011-09-01

    The aim of this study is to correct the misunderstanding that the toxicity of organic mercury compounds is unknown at the time of the outbreak of Minamata disease (May 1, 1956). Two case reports of organic mercury (methylmercury) intoxication were published already in 1865 and 1866. The conversion of inorganic mercury added in acetoaldehyde synthesis was already pointed out in 1921. In 1930 several cases of organic mercury poisoning among workers engaged in acetoaldehyde production were reported. Many reports on not only in occupational exposure but a oral exposure via the ingestion of flour made from grains treated with organic mercurials were available at the time of the outbreak of Minamata disease (May 1, 1956). These reports pointed out the toxic effects of organic mercury on the central nervous system, and indicated cleary that the causal substance of Minamata disease must be the organic mercury compounds (methylmercury) from the Chisso plant. The identification of methylmercury as the causal substance by the authority was presented in 1968 when acetoaldehyde production in the Chisso plant was closed. Most of these reports except that of (Hunter et al.) were not referred to in the study of Minamata disease . Inadequate referencing should be pointed out. Several reports indicated that the causal substance of Minamata disease must be methylmercury from the Chisso Plant. However, most of these reports were not referred to during the study of Minamata disease. Inadequate referencing of literatures should be pointed out.

  13. Origins, fates, and ramifications of natural organic compounds of wetlands

    Treesearch

    Robert G. Wetzel

    2000-01-01

    Much of the organic carbon for heterotrophic metabolism in aquatic ecosystems is soluble and derived from structural compounds of higher plants of terrestrial and wetland-littoral sources of both lake and river ecosystems. The chemical recalcitrance of this organic matter and its oxidative utilization are fundamentally different from many sources within the aquatic...

  14. Engineering biosynthesis of high-value compounds in photosynthetic organisms.

    PubMed

    O'Neill, Ellis C; Kelly, Steven

    2017-09-01

    The photosynthetic, autotrophic lifestyle of plants and algae position them as ideal platform organisms for sustainable production of biomolecules. However, their use in industrial biotechnology is limited in comparison to heterotrophic organisms, such as bacteria and yeast. This usage gap is in part due to the challenges in generating genetically modified plants and algae and in part due to the difficulty in the development of synthetic biology tools for manipulating gene expression in these systems. Plant and algal metabolism, pre-installed with multiple biosynthetic modules for precursor compounds, bypasses the requirement to install these pathways in conventional production organisms, and creates new opportunities for the industrial production of complex molecules. This review provides a broad overview of the successes, challenges and future prospects for genetic engineering in plants and algae for enhanced or de novo production of biomolecules. The toolbox of technologies and strategies that have been used to engineer metabolism are discussed, and the potential use of engineered plants for industrial manufacturing of large quantities of high-value compounds is explored. This review also discusses the routes that have been taken to modify the profiles of primary metabolites for increasing the nutritional quality of foods as well as the production of specialized metabolites, cosmetics, pharmaceuticals and industrial chemicals. As the universe of high-value biosynthetic pathways continues to expand, and the tools to engineer these pathways continue to develop, it is likely plants and algae will become increasingly valuable for the biomanufacturing of high-value compounds.

  15. 75 FR 57412 - Approval and Promulgation of Implementation Plans Alabama: Volatile Organic Compounds

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-21

    ...] Approval and Promulgation of Implementation Plans Alabama: Volatile Organic Compounds AGENCY: Environmental... compounds'' (VOCs) found at Alabama Administrative Code section 335-3-1-.02(gggg). Specifically, the revision would add two compounds (propylene carbonate and dimethyl carbonate) to the list of those excluded...

  16. Modeling emissions of volatile organic compounds from silage

    USDA-ARS?s Scientific Manuscript database

    Photochemical smog is a major air pollution problem and a significant cause of premature death in the U.S. Smog forms in the presence of volatile organic compounds (VOCs), which are emitted primarily from industry and motor vehicles in the U.S. However, dairy farms may be an important source in so...

  17. Temporal dynamics of halogenated organic compounds in Marcellus Shale flowback.

    PubMed

    Luek, Jenna L; Harir, Mourad; Schmitt-Kopplin, Philippe; Mouser, Paula J; Gonsior, Michael

    2018-06-01

    The chemistry of hydraulic fracturing fluids and wastewaters is complex and is known to vary by operator, geologic formation, and fluid age. A time series of hydraulic fracturing fluids, flowback fluids, and produced waters was collected from two adjacent Marcellus Shale gas wells for organic chemical composition analyses using ultrahigh resolution mass spectrometry. Hierarchical clustering was used to compare and extract ions related to different fluid ages and many halogenated organic molecular ions were identified in flowback fluids and early produced waters based on exact mass. Iodinated organic compounds were the dominant halogen class in these clusters and were nearly undetectable in hydraulic fracturing fluid prior to injection. The iodinated ions increased in flowback and remained elevated after ten months of well production. We suggest that these trends are mainly driven by dissolved organic matter reacting with reactive halogen species formed abiotically through oxidizing chemical additives applied to the well and biotically via iodide-oxidizing bacteria. Understanding the implications of these identified halogenated organic compounds will require future investigation in to their structures and environmental fate. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. IMPROVEMENT IN AIR TOXICS METHODS FOR VOLATILE ORGANIC COMPOUNDS

    EPA Science Inventory

    Innovative and customized monitoring methods for air toxic volatile organic compounds (VOCs) are being developed for applications in exposure and trends monitoring. This task addresses the following applications of specific interest:

    o Contributions to EPA Regional Monit...

  19. COMPACT, CONTINUOUS MONITORING FOR VOLATILE ORGANIC COMPOUNDS - PHASE I

    EPA Science Inventory

    Improved methods for onsite measurement of multiple volatile organic compounds are needed for process control, monitoring, and remediation. This Phase I SBIR project sets forth an optical measurement method that meets these needs. The proposed approach provides an instantaneous m...

  20. MICROBIAL VOLATILE ORGANIC COMPOUND EMISSION RATES AND EXPOSURE MODEL

    EPA Science Inventory

    This paper presents the results from a study that examined microbial volatile organic compound (MVOC) emissions from six fungi and one bacterial species (Streptomyces spp.) commonly found in indoor environments. Data are presented on peak emission rates from inoculated agar plate...

  1. Generation of Volatile Organic Compounds from Dissolved Organic Matter in far North Atlantic Surface Ocean Waters.

    NASA Astrophysics Data System (ADS)

    Hudson, E. D.; Ariya, P. A.

    2005-12-01

    The photochemical degradation of dissolved organic matter (DOM) in surface ocean waters is thought to be a source of volatile organic compounds (VOC) (including non-methane hydrocarbons and low MW carbonyl compounds) to the remote marine troposphere. We report on the characterization of DOM sampled at over 30 sites in the far North Atlantic (Greenland and Norwegian seas, Fram strait) during the summer of 2004, and on experiments to identify factors responsible for the photochemical generation of VOCs in these samples. The results will be discussed in the context of VOC profiles of whole air samples taken to match the seawater samples in time and space.

  2. Cloud processing of organic compounds: Secondary organic aerosol and nitrosamine formation

    NASA Astrophysics Data System (ADS)

    Hutchings, James W., III

    Cloud processing of atmospheric organic compounds has been investigated through field studies, laboratory experiments, and numerical modeling. Observational cloud chemistry studies were performed in northern Arizona and fog studies in central Pennsylvania. At both locations, the cloud and fogs showed low acidity due to neutralization by soil dust components (Arizona) and ammonia (Pennsylvania). The field observations showed substantial concentrations (20-5500 ng•L -1) of volatile organic compounds (VOC) in the cloud droplets. The potential generation of secondary organic aerosol mass through the processing of these anthropogenic VOCs was investigated through laboratory and modeling studies. Under simulated atmospheric conditions, in idealized solutions, benzene, toluene, ethylbenzene, and xylene (BTEX) degraded quickly in the aqueous phase with half lives of approximately three hours. The degradation process yielded less volatile products which would contribute to new aerosol mass upon cloud evaporation. However, when realistic cloud solutions containing natural organic matter were used in the experiments, the reaction kinetics decreased with increasing organic carbon content, resulting in half lives of approximately 7 hours. The secondary organic aerosol (SUA) mass formation potential of cloud processing of BTEX was evaluated. SOA mass formation by cloud processing of BTEX, while strongly dependent on the atmospheric conditions, could contribute up to 9% of the ambient atmospheric aerosol mass, although typically ˜1% appears realistic. Field observations also showed the occurrence of N-nitrosodimethylamine (NDMA), a potent carcinogen, in fogs and clouds (100-340 ng•L -1). Laboratory studies were conducted to investigate the formation of NDMA from nitrous acid and dimethylamine in the homogeneous aqueous phase within cloud droplets. While NDMA was produced in the cloud droplets, the low yields (<1%) observed could not explain observational concentrations

  3. Deuterium enrichment by selective photo-induced dissociation of an organic carbonyl compound

    DOEpatents

    Marling, John B.

    1981-01-01

    A method for producing a deuterium enriched material by photoinduced dissociation which uses as the working material a gas phase photolytically dissociable organic carbonyl compound containing at least one hydrogen atom bonded to an atom which is adjacent to a carbonyl group and consisting of molecules wherein said hydrogen atom is present as deuterium and molecules wherein said hydrogen atom is present as another isotope of hydrogen. The organic carbonyl compound is subjected to intense infrared radiation at a preselected wavelength to selectively excite and thereby induce dissociation of the deuterium containing species to yield a deuterium enriched stable molecular product. Undissociated carbonyl compound, depleted in deuterium, is preferably redeuterated for reuse.

  4. Investigation of extractable organic compounds in deep-sea hydrothermal vent fluids along the Mid-Atlantic Ridge

    NASA Astrophysics Data System (ADS)

    McCollom, Thomas M.; Seewald, Jeffrey S.; German, Christopher R.

    2015-05-01

    The possibility that deep-sea hydrothermal vents may contain organic compounds produced by abiotic synthesis or by microbial communities living deep beneath the surface has led to numerous studies of the organic composition of vent fluids. Most of these studies have focused on methane and other light hydrocarbons, while the possible occurrence of more complex organic compounds in the fluids has remained largely unstudied. To address this issue, the presence of higher molecular weight organic compounds in deep-sea hydrothermal fluids was assessed at three sites along the Mid-Atlantic Ridge that span a range of temperatures (51 to >360 °C), fluid compositions, and host-rock lithologies (mafic to ultramafic). Samples were obtained at several sites within the Lucky Strike, Rainbow, and Lost City hydrothermal fields. Three methods were employed to extract organic compounds for analysis, including liquid:liquid extraction, cold trapping on the walls of a coil of titanium tubing, and pumping fluids through cartridges filled with solid phase extraction (SPE) sorbents. The only samples to consistently yield high amounts of extractable organic compounds were the warm (51-91 °C), highly alkaline fluids from Lost City, which contained elevated concentrations of C8, C10, and C12n-alkanoic acids and, in some cases, trithiolane, hexadecanol, squalene, and cholesterol. Collectively, the C8-C12 acids can account for about 15% of the total dissolved organic carbon in the Lost City fluids. The even-carbon-number predominance of the alkanoic acids indicates a biological origin, but it is unclear whether these compounds are derived from microbial activity occurring within the hydrothermal chimney proximal to the site of fluid discharge or are transported from deeper within the system. Hydrothermal fluids from the Lucky Strike and Rainbow fields were characterized by an overall scarcity of extractable dissolved organic compounds. Trace amounts of aromatic hydrocarbons including

  5. The composition of the primitive atmosphere and the synthesis of organic compounds on the early Earth

    NASA Technical Reports Server (NTRS)

    Bada, J. L.; Miller, S. L.

    1985-01-01

    The generally accepted theory for the origin of life on the Earth requires that a large variety of organic compounds be present to form the first living organisms and to provide the energy sources for primitive life either directly or through various fermentation reactions. This can provide a strong constraint on discussions of the formation of the Earth and on the composition of the primitive atmosphere. In order for substantial amounts of organic compounds to have been present on the prebiological Earth, certain conditions must have existed. There is a large body of literature on the prebiotic synthesis of organic compounds in various postulated atmospheres. In this mixture of abiotically synthesized organic compounds, the amino acids are of special interest since they are utilized by modern organisms to synthesize structural materials and a large array of catalytic peptides.

  6. Henry`s law constant for selected volatile organic compounds in high-boiling oils

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Poddar, T.K.; Sirkar, K.K.

    Absorption systems are often used to remove and recover organic vapors from process air/gas streams. A high boiling and inert liquid like silicone oil is an excellent absorbent for volatile organic compounds in air. Henry`s law constants of four different volatile organic compounds, namely, acetone, methanol, methylene chloride, and toluene between air and high-boiling oils were determined experimentally by the headspace-GC technique over a temperature range. The Henry`s law constants were fitted as a function of temperature to an equation.

  7. Understanding the toxicological potential of aerosol organic compounds using informatics based screening

    NASA Astrophysics Data System (ADS)

    Topping, David; Decesari, Stefano; Bassan, Arianna; Pavan, Manuela; Ciacci, Andrea

    2016-04-01

    Exposure to atmospheric particulate matter is responsible for both short-term and long-term adverse health effects. So far, all efforts spent in achieving a systematic epidemiological evidence of specific aerosol compounds determining the overall aerosol toxicity were unsuccessful. The results of the epidemiological studies apparently conflict with the laboratory toxicological analyses which have highlighted very different chemical and toxicological potentials for speciated aerosol compounds. Speciation remains a problem, especially for organic compounds: it is impossible to conduct screening on all possible molecular species. At the same time, research on toxic compounds risks to be biased towards the already known compounds, such as PAHs and dioxins. In this study we present results from an initial assessment of the use of in silico methods (i.e. (Q)SAR, read-across) to predict toxicity of atmospheric organic compounds including evaluation of applicability of a variety of popular tools (e.g. OECD QSAR Toolbox) for selected endpoints (e.g. genotoxicity). Compounds are categorised based on the need of new experimental data for the development of in silico approaches for toxicity prediction covering this specific chemical space, namely the atmospheric aerosols. Whilst only an initial investigation, we present recommendations for continuation of this work.

  8. Organic compounds in produced waters from shale gas wells.

    PubMed

    Maguire-Boyle, Samuel J; Barron, Andrew R

    2014-01-01

    A detailed analysis is reported of the organic composition of produced water samples from typical shale gas wells in the Marcellus (PA), Eagle Ford (TX), and Barnett (NM) formations. The quality of shale gas produced (and frac flowback) waters is a current environmental concern and disposal problem for producers. Re-use of produced water for hydraulic fracturing is being encouraged; however, knowledge of the organic impurities is important in determining the method of treatment. The metal content was determined by inductively coupled plasma optical emission spectrometry (ICP-OES). Mineral elements are expected depending on the reservoir geology and salts used in hydraulic fracturing; however, significant levels of other transition metals and heavier main group elements are observed. The presence of scaling elements (Ca and Ba) is related to the pH of the water rather than total dissolved solids (TDS). Using gas chromatography mass spectrometry (GC/MS) analysis of the chloroform extracts of the produced water samples, a plethora of organic compounds were identified. In each water sample, the majority of organics are saturated (aliphatic), and only a small fraction comes under aromatic, resin, and asphaltene categories. Unlike coalbed methane produced water it appears that shale oil/gas produced water does not contain significant quantities of polyaromatic hydrocarbons reducing the potential health hazard. Marcellus and Barnett produced waters contain predominantly C6-C16 hydrocarbons, while the Eagle Ford produced water shows the highest concentration in the C17-C30 range. The structures of the saturated hydrocarbons identified generally follows the trend of linear > branched > cyclic. Heterocyclic compounds are identified with the largest fraction being fatty alcohols, esters, and ethers. However, the presence of various fatty acid phthalate esters in the Barnett and Marcellus produced waters can be related to their use in drilling fluids and breaker additives

  9. Fatty acids and small organic compounds bind to mineralo-organic nanoparticles derived from human body fluids as revealed by metabolomic analysis.

    PubMed

    Martel, Jan; Wu, Cheng-Yeu; Hung, Cheng-Yu; Wong, Tsui-Yin; Cheng, Ann-Joy; Cheng, Mei-Ling; Shiao, Ming-Shi; Young, John D

    2016-03-14

    Nanoparticles entering the human body instantly become coated with a "protein corona" that influences the effects and distribution of the particles in vivo. Yet, whether nanoparticles may bind to other organic compounds remains unclear. Here we use an untargeted metabolomic approach based on ultra-performance liquid chromatography and quadruple time-of-flight mass spectrometry to identify the organic compounds that bind to mineral nanoparticles formed in human body fluids (serum, plasma, saliva, and urine). A wide range of organic compounds is identified, including fatty acids, glycerophospholipids, amino acids, sugars, and amides. Our results reveal that, in addition to the proteins identified previously, nanoparticles harbor an "organic corona" containing several fatty acids which may affect particle-cell interactions in vivo. This study provides a platform to study the organic corona of biological and synthetic nanoparticles found in the human body.

  10. Indoor Semi-volatile Organic Compounds (i-SVOC) Version 1.0

    EPA Pesticide Factsheets

    i-SVOC Version 1.0 is a general-purpose software application for dynamic modeling of the emission, transport, sorption, and distribution of semi-volatile organic compounds (SVOCs) in indoor environments.

  11. Application of organic compounds for high-order harmonic generation of ultrashort pulses

    NASA Astrophysics Data System (ADS)

    Ganeev, R. A.

    2016-02-01

    The studies of the high-order nonlinear optical properties of a few organic compounds (polyvinyl alcohol, polyethylene, sugar, coffee, and leaf) are reported. Harmonic generation in the laser-produced plasmas containing the molecules and large particles of above materials is demonstrated. These studies showed that the harmonic distributions and harmonic cutoffs from organic compound plasmas were similar to those from the graphite ablation. The characteristic feature of observed harmonic spectra was the presence of bluesided lobes near the lower-order harmonics.

  12. Detecting Organic Compounds in Martian Soil Analogues Using Gas Chromatography Mass Spectrometry

    NASA Technical Reports Server (NTRS)

    Glavin, D. P.; Buch, A.; Mahaffy, P. R.

    2004-01-01

    One of the primary objectives of the 1976 Viking missions was to determine whether organic compounds, possibly of biological origin, were present in the Martian surface soils. The Viking gas chromatography mass spectrometry (GCMS) instruments found no evidence for any organic compounds of Martian origin above a few parts per billion in the upper 10 cm of surface soil [l], suggesting the absence of a widely distributed Martian biota. However, Benner et d. have suggested that significant amounts of non-volatile organic compounds, possibly including oxidation products of bioorganic molecules (e.g. carboxylic acids) would not have been detected by the Viking GCMS [2]. Moreover, other key organic compounds important to biology, such as amino acids and nucleobases, would also likely have been missed by the Viking GCMS as these compounds require chemical derivatization to be stable in a GC column [3]. Recent pyrolysis experiments with a Mars soil analogue that had been innoculated with Escherichia coli bacteria have shown that amino acid decomposition products (amines) and nucleobases are among the most abundant products generated after pyrolysis of the bacterial cells [4,5]. At the part per billion level (Viking GCMS detection limit), these pyrolysis products generated from several million bacterial cells per gram of Martian soil would not have been detected by the Viking GCMS instruments [4]. Analytical protocols are under development for upcoming in situ lander opportunities to target several important biological compounds including amino acids and nucleobases. For example, extraction and chemical derivatization techniques [3] are being adapted for space flight use to transform reactive or fragile molecules that would not have been detected by the Viking GCMS instruments, into species that are sufficiently volatile to be detected by GCMS. Recent experiments carried out at NASA Goddard have shown that using this derivatization technique all of the targeted compounds

  13. Biogenic, urban, and wildfire influences on the molecular composition of dissolved organic compounds in cloud water

    DOE PAGES

    Cook, Ryan D.; Lin, Ying-Hsuan; Peng, Zhuoyu; ...

    2017-12-21

    Organic aerosol formation and transformation occurs within aqueous aerosol and cloud droplets, yet little is known about the composition of high molecular weight organic compounds in cloud water. Cloud water samples collected at Whiteface Mountain, New York, during August-September 2014 were analyzed by ultra-high-resolution mass spectrometry to investigate the molecular composition of dissolved organic carbon, with a focus on sulfur- and nitrogen-containing compounds. Organic molecular composition was evaluated in the context of cloud water inorganic ion concentrations, pH, and total organic carbon concentrations to gain insights into the sources and aqueous-phase processes of the observed high molecular weight organic compounds.more » Cloud water acidity was positively correlated with the average oxygen : carbon ratio of the organic constituents, suggesting the possibility for aqueous acid-catalyzed (prior to cloud droplet activation or during/after cloud droplet evaporation) and/or radical (within cloud droplets) oxidation processes. Many tracer compounds recently identified in laboratory studies of bulk aqueous-phase reactions were identified in the cloud water. Organosulfate compounds, with both biogenic and anthropogenic volatile organic compound precursors, were detected for cloud water samples influenced by air masses that had traveled over forested and populated areas. Oxidation products of long-chain (C 10-12) alkane precursors were detected during urban influence. Influence of Canadian wildfires resulted in increased numbers of identified sulfur-containing compounds and oligomeric species, including those formed through aqueous-phase reactions involving methylglyoxal. Light-absorbing aqueous-phase products of syringol and guaiacol oxidation were observed in the wildfire-influenced samples, and dinitroaromatic compounds were observed in all cloud water samples (wildfire, biogenic, and urban-influenced). Overall, the cloud water molecular composition

  14. Biogenic, urban, and wildfire influences on the molecular composition of dissolved organic compounds in cloud water

    NASA Astrophysics Data System (ADS)

    Cook, Ryan D.; Lin, Ying-Hsuan; Peng, Zhuoyu; Boone, Eric; Chu, Rosalie K.; Dukett, James E.; Gunsch, Matthew J.; Zhang, Wuliang; Tolic, Nikola; Laskin, Alexander; Pratt, Kerri A.

    2017-12-01

    Organic aerosol formation and transformation occurs within aqueous aerosol and cloud droplets, yet little is known about the composition of high molecular weight organic compounds in cloud water. Cloud water samples collected at Whiteface Mountain, New York, during August-September 2014 were analyzed by ultra-high-resolution mass spectrometry to investigate the molecular composition of dissolved organic carbon, with a focus on sulfur- and nitrogen-containing compounds. Organic molecular composition was evaluated in the context of cloud water inorganic ion concentrations, pH, and total organic carbon concentrations to gain insights into the sources and aqueous-phase processes of the observed high molecular weight organic compounds. Cloud water acidity was positively correlated with the average oxygen : carbon ratio of the organic constituents, suggesting the possibility for aqueous acid-catalyzed (prior to cloud droplet activation or during/after cloud droplet evaporation) and/or radical (within cloud droplets) oxidation processes. Many tracer compounds recently identified in laboratory studies of bulk aqueous-phase reactions were identified in the cloud water. Organosulfate compounds, with both biogenic and anthropogenic volatile organic compound precursors, were detected for cloud water samples influenced by air masses that had traveled over forested and populated areas. Oxidation products of long-chain (C10-12) alkane precursors were detected during urban influence. Influence of Canadian wildfires resulted in increased numbers of identified sulfur-containing compounds and oligomeric species, including those formed through aqueous-phase reactions involving methylglyoxal. Light-absorbing aqueous-phase products of syringol and guaiacol oxidation were observed in the wildfire-influenced samples, and dinitroaromatic compounds were observed in all cloud water samples (wildfire, biogenic, and urban-influenced). Overall, the cloud water molecular composition depended on

  15. Biogenic, urban, and wildfire influences on the molecular composition of dissolved organic compounds in cloud water

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cook, Ryan D.; Lin, Ying-Hsuan; Peng, Zhuoyu

    Organic aerosol formation and transformation occurs within aqueous aerosol and cloud droplets, yet little is known about the composition of high molecular weight organic compounds in cloud water. Cloud water samples collected at Whiteface Mountain, New York, during August-September 2014 were analyzed by ultra-high-resolution mass spectrometry to investigate the molecular composition of dissolved organic carbon, with a focus on sulfur- and nitrogen-containing compounds. Organic molecular composition was evaluated in the context of cloud water inorganic ion concentrations, pH, and total organic carbon concentrations to gain insights into the sources and aqueous-phase processes of the observed high molecular weight organic compounds.more » Cloud water acidity was positively correlated with the average oxygen : carbon ratio of the organic constituents, suggesting the possibility for aqueous acid-catalyzed (prior to cloud droplet activation or during/after cloud droplet evaporation) and/or radical (within cloud droplets) oxidation processes. Many tracer compounds recently identified in laboratory studies of bulk aqueous-phase reactions were identified in the cloud water. Organosulfate compounds, with both biogenic and anthropogenic volatile organic compound precursors, were detected for cloud water samples influenced by air masses that had traveled over forested and populated areas. Oxidation products of long-chain (C 10-12) alkane precursors were detected during urban influence. Influence of Canadian wildfires resulted in increased numbers of identified sulfur-containing compounds and oligomeric species, including those formed through aqueous-phase reactions involving methylglyoxal. Light-absorbing aqueous-phase products of syringol and guaiacol oxidation were observed in the wildfire-influenced samples, and dinitroaromatic compounds were observed in all cloud water samples (wildfire, biogenic, and urban-influenced). Overall, the cloud water molecular composition

  16. Transformations of organic compounds under the action of mechanical stress

    NASA Astrophysics Data System (ADS)

    Dubinskaya, Aleksandra M.

    1999-08-01

    Transformations of organic compounds (monomeric and polymeric) under the action of mechanical stress are considered. Two types of processes occur under these conditions. The first type involves disordering and amorphisation of crystal structure and conformational transformations as a result of rupture of intermolecular bonds. The second type includes mechanochemical reactions activated by deformation of valence bonds and angles under mechanical stress, namely, the rupture of bonds, oxidation and hydrolysis. Data on the organic mechanochemical synthesis of new compounds or molecular complexes are systematised and generalised. It is demonstrated that mechanical treatment ensures mass transfer and the contact of reacting species in these reactions. Proteins are especially sensitive to mechanical stress and undergo denaturation; enzymes are inactivated. The bibliography includes 115 references.

  17. 75 FR 2090 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Volatile Organic Compound...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-14

    ... Promulgation of Air Quality Implementation Plans; Indiana; Volatile Organic Compound Automobile Refinishing... automobile refinishing rule for approval into its State Implementation Plan (SIP). These rule revisions extend the applicability of Indiana's approved volatile organic compound (VOC) automobile refinishing...

  18. Volatile organic compounds: sampling methods and their worldwide profile in ambient air.

    PubMed

    Kumar, Anuj; Víden, Ivan

    2007-08-01

    The atmosphere is a particularly difficult analytical system because of the very low levels of substances to be analysed, sharp variations in pollutant levels with time and location, differences in wind, temperature and humidity. This makes the selection of an efficient sampling technique for air analysis a key step to reliable results. Generally, methods for volatile organic compounds sampling include collection of the whole air or preconcentration of samples on adsorbents. All the methods vary from each other according to the sampling technique, type of sorbent, method of extraction and identification technique. In this review paper we discuss various important aspects for sampling of volatile organic compounds by the widely used and advanced sampling methods. Characteristics of various adsorbents used for VOCs sampling are also described. Furthermore, this paper makes an effort to comprehensively review the concentration levels of volatile organic compounds along with the methodology used for analysis, in major cities of the world.

  19. Volatile organic compound sensing devices

    DOEpatents

    Lancaster, G.D.; Moore, G.A.; Stone, M.L.; Reagen, W.K.

    1995-08-29

    Apparatus employing vapochromic materials in the form of inorganic double complex salts which change color reversibly when exposed to volatile organic compound (VOC) vapors is adapted for VOC vapor detection, VOC aqueous matrix detection, and selective VOC vapor detection. The basic VOC vapochromic sensor is incorporated in various devices such as a ground probe sensor, a wristband sensor, a periodic sampling monitor, a soil/water penetrometer, an evaporative purge sensor, and various vacuum-based sensors which are particularly adapted for reversible/reusable detection, remote detection, continuous monitoring, or rapid screening of environmental remediation and waste management sites. The vapochromic sensor is used in combination with various fiber optic arrangements to provide a calibrated qualitative and/or quantitative indication of the presence of VOCs. 15 figs.

  20. Volatile organic compound sensing devices

    DOEpatents

    Lancaster, Gregory D.; Moore, Glenn A.; Stone, Mark L.; Reagen, William K.

    1995-01-01

    Apparatus employing vapochromic materials in the form of inorganic double complex salts which change color reversibly when exposed to volatile organic compound (VOC) vapors is adapted for VOC vapor detection, VOC aqueous matrix detection, and selective VOC vapor detection. The basic VOC vapochromic sensor is incorporated in various devices such as a ground probe sensor, a wristband sensor, a periodic sampling monitor, a soil/water penetrometer, an evaporative purge sensor, and various vacuum-based sensors which are particularly adapted for reversible/reusable detection, remote detection, continuous monitoring, or rapid screening of environmental remediation and waste management sites. The vapochromic sensor is used in combination with various fiber optic arrangements to provide a calibrated qualitative and/or quantitative indication of the presence of VOCs.

  1. MEASUREMENT OF ORGANIC COMPOUND EMISSIONS USING SMALL TEST CHAMBERS

    EPA Science Inventory

    Organic compounds emitted from a variety of indoor materials have been measured using small (166 L) environmental test chambers. The paper discusses: a) factors to be considered in small chamber testing; b) parameters to be controlled; c) the types of results obtained. The follow...

  2. Effects and mechanistic aspects of absorbing organic compounds by coking coal.

    PubMed

    Ning, Kejia; Wang, Junfeng; Xu, Hongxiang; Sun, Xianfeng; Huang, Gen; Liu, Guowei; Zhou, Lingmei

    2017-11-01

    Coal is a porous medium and natural absorbent. It can be used for its original purpose after adsorbing organic compounds, its value does not reduce and the pollutants are recycled, and then through systemic circulation of coking wastewater zero emissions can be achieved. Thus, a novel method of industrial organic wastewater treatment using adsorption on coal is introduced. Coking coal was used as an adsorbent in batch adsorption experiments. The quinoline, indole, pyridine and phenol removal efficiencies of coal adsorption were investigated. In addition, several operating parameters which impact removal efficiency such as coking coal consumption, oscillation contact time, initial concentration and pH value were also investigated. The coking coal exhibited properties well-suited for organics' adsorption. The experimental data were fitted to Langmuir and Freundlich isotherms as well as Temkin and Redlich-Peterson (R-P) models. The Freundlich isotherm model provided reasonable models of the adsorption process. Furthermore, the purification mechanism of organic compounds' adsorption on coking coal was analysed.

  3. 15 CFR 715.1 - Annual declaration requirements for production by synthesis of unscheduled discrete organic...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... production by synthesis of unscheduled discrete organic chemicals (UDOCs). 715.1 Section 715.1 Commerce and... DISCRETE ORGANIC CHEMICALS (UDOCs) § 715.1 Annual declaration requirements for production by synthesis of unscheduled discrete organic chemicals (UDOCs). (a) Declaration of production by synthesis of UDOCs for...

  4. 15 CFR 715.1 - Annual declaration requirements for production by synthesis of unscheduled discrete organic...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... production by synthesis of unscheduled discrete organic chemicals (UDOCs). 715.1 Section 715.1 Commerce and... DISCRETE ORGANIC CHEMICALS (UDOCs) § 715.1 Annual declaration requirements for production by synthesis of unscheduled discrete organic chemicals (UDOCs). (a) Declaration of production by synthesis of UDOCs for...

  5. 15 CFR 715.1 - Annual declaration requirements for production by synthesis of unscheduled discrete organic...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... production by synthesis of unscheduled discrete organic chemicals (UDOCs). 715.1 Section 715.1 Commerce and... DISCRETE ORGANIC CHEMICALS (UDOCs) § 715.1 Annual declaration requirements for production by synthesis of unscheduled discrete organic chemicals (UDOCs). (a) Declaration of production by synthesis of UDOCs for...

  6. 15 CFR 715.1 - Annual declaration requirements for production by synthesis of unscheduled discrete organic...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... production by synthesis of unscheduled discrete organic chemicals (UDOCs). 715.1 Section 715.1 Commerce and... DISCRETE ORGANIC CHEMICALS (UDOCs) § 715.1 Annual declaration requirements for production by synthesis of unscheduled discrete organic chemicals (UDOCs). (a) Declaration of production by synthesis of UDOCs for...

  7. 15 CFR 715.1 - Annual declaration requirements for production by synthesis of unscheduled discrete organic...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... production by synthesis of unscheduled discrete organic chemicals (UDOCs). 715.1 Section 715.1 Commerce and... DISCRETE ORGANIC CHEMICALS (UDOCs) § 715.1 Annual declaration requirements for production by synthesis of unscheduled discrete organic chemicals (UDOCs). (a) Declaration of production by synthesis of UDOCs for...

  8. IDENTIFICATION AND QUANTIFICATION OF AEROSOL POLAR OXYGENATED COMPOUNDS BEARING CARBOXYLIC OR HYDROXYL GROUPS. 2. ORGANIC TRACER COMPOUNDS FROM MONOTERPENES

    EPA Science Inventory

    A comparison was made of polar organic compounds found in the field with those produced in secondary organic aerosol from laboratory irradiations of natural hydrocarbons and oxides of nitrogen. The field samples comprised atmospheric particulate matter (PM2.5) collect...

  9. Quantitative prediction of solvation free energy in octanol of organic compounds.

    PubMed

    Delgado, Eduardo J; Jaña, Gonzalo A

    2009-03-01

    The free energy of solvation, DeltaGS0, in octanol of organic compounds is quantitatively predicted from the molecular structure. The model, involving only three molecular descriptors, is obtained by multiple linear regression analysis from a data set of 147 compounds containing diverse organic functions, namely, halogenated and non-halogenated alkanes, alkenes, alkynes, aromatics, alcohols, aldehydes, ketones, amines, ethers and esters; covering a DeltaGS0 range from about -50 to 0 kJ.mol(-1). The model predicts the free energy of solvation with a squared correlation coefficient of 0.93 and a standard deviation, 2.4 kJ.mol(-1), just marginally larger than the generally accepted value of experimental uncertainty. The involved molecular descriptors have definite physical meaning corresponding to the different intermolecular interactions occurring in the bulk liquid phase. The model is validated with an external set of 36 compounds not included in the training set.

  10. Thermal engine driven heat pump for recovery of volatile organic compounds

    DOEpatents

    Drake, Richard L.

    1991-01-01

    The present invention relates to a method and apparatus for separating volatile organic compounds from a stream of process gas. An internal combustion engine drives a plurality of refrigeration systems, an electrical generator and an air compressor. The exhaust of the internal combustion engine drives an inert gas subsystem and a heater for the gas. A water jacket captures waste heat from the internal combustion engine and drives a second heater for the gas and possibly an additional refrigeration system for the supply of chilled water. The refrigeration systems mechanically driven by the internal combustion engine effect the precipitation of volatile organic compounds from the stream of gas.

  11. Deuterium enrichment by selective photoinduced dissociation of a multihalogenated organic compound

    DOEpatents

    Marling, John B.; Herman, Irving P.

    1981-01-01

    A method for deuterium enrichment by photoinduced dissociation which uses as the deuterium source a multihalogenated organic compound selected from the group consisting of a dihalomethane, a trihalomethane, a 1,2-dihaloethene, a trihaloethene, a tetrahaloethane and a pentahaloethane. The multihalogenated organic compound is subjected to intense infrared radiation at a preselected wavelength to selectively excite and thereby induce dissociation of substantially only those molecules containing deuterium to provide a deuterium enriched dissociation product. The deuterium enriched product may be combusted with oxygen to provide deuterium enriched water. The deuterium depleted undissociated molecules may be redeuterated by treatment with a deuterium source such as water.

  12. Evidence from the Pacific troposphere for large global sources of oxygenated organic compounds

    NASA Astrophysics Data System (ADS)

    Singh, H.; Chen, Y.; Staudt, A.; Jacob, D.; Blake, D.; Heikes, B.; Snow, J.

    2001-04-01

    The presence of oxygenated organic compounds in the troposphere strongly influences key atmospheric processes. Such oxygenated species are, for example, carriers of reactive nitrogen and are easily photolysed, producing free radicals-and so influence the oxidizing capacity and the ozone-forming potential of the atmosphere-and may also contribute significantly to the organic component of aerosols. But knowledge of the distribution and sources of oxygenated organic compounds, especially in the Southern Hemisphere, is limited. Here we characterize the tropospheric composition of oxygenated organic species, using data from a recent airborne survey conducted over the tropical Pacific Ocean (30°N to 30°S). Measurements of a dozen oxygenated chemicals (carbonyls, alcohols, organic nitrates, organic pernitrates and peroxides), along with several C2-C8 hydrocarbons, reveal that abundances of oxygenated species are extremely high, and collectively, oxygenated species are nearly five times more abundant than non-methane hydrocarbons in the Southern Hemisphere. Current atmospheric models are unable to correctly simulate these findings, suggesting that large, diffuse, and hitherto-unknown sources of oxygenated organic compounds must therefore exist. Although the origin of these sources is still unclear, we suggest that oxygenated species could be formed via the oxidation of hydrocarbons in the atmosphere, the photochemical degradation of organic matter in the oceans, and direct emissions from terrestrial vegetation.

  13. A review of surface-water sediment fractions and their interactions with persistent manmade organic compounds

    USGS Publications Warehouse

    Witkowski, P.J.; Smith, J.A.; Fusillo, T.V.; Chiou, C.T.

    1987-01-01

    This paper reviews the suspended and surficial sediment fractions and their interactions with manmade organic compounds. The objective of this review is to isolate and describe those contaminant and sediment properties that contribute to the persistence of organic compounds in surface-water systems. Most persistent, nonionic organic contaminants, such as the chlorinated insecticides and polychlorinated biphenyls (PCBs), are characterized by low water solubilities and high octanol-water partition coefficients. Consequently, sorptive interactions are the primary transformation processes that control their environmental behavior. For nonionic organic compounds, sorption is primarily attributed to the partitioning of an organic contaminant between a water phase and an organic phase. Partitioning processes play a central role in the uptake and release of contaminants by sediment organic matter and in the bioconcentration of contaminants by aquatic organisms. Chemically isolated sediment fractions show that organic matter is the primary determinant of the sorptive capacity exhibited by sediment. Humic substances, as dissolved organic matter, contribute a number of functions to the processes cycling organic contaminants. They alter the rate of transformation of contaminants, enhance apparent water solubility, and increase the carrying capacity of the water column beyond the solubility limits of the contaminant. As a component of sediment particles, humic substances, through sorptive interactions, serve as vectors for the hydrodynamic transport of organic contaminants. The capabilities of the humic substances stem in part from their polyfunctional chemical composition and also from their ability to exist in solution as dissolved species, flocculated aggregates, surface coatings, and colloidal organomineral and organometal complexes. The transport properties of manmade organic compounds have been investigated by field studies and laboratory experiments that examine the

  14. Volatile organic compounds of whole grain soft winter wheat

    USDA-ARS?s Scientific Manuscript database

    The aroma from volatile organic compounds (VOCs) is an indicator of grain soundness and also an important quality attribute of grain foods. To identify the inherent VOCs of wheat grain unaffected by fungal infestation and other extrinsic factors, grains of nine soft wheat varieties were collected at...

  15. Analysis of 34S in Individual Organic Compounds by Coupled GC-ICP-MS

    NASA Astrophysics Data System (ADS)

    Sessions, A. L.; Amrani, A.; Adkins, J. F.

    2009-12-01

    The abundances of 2H, 13C, and 15N in organic compounds have been extremely useful in many aspects of biogeochemistry. While sulfur plays an equally important role in many earth-surface processes, the isotopes of sulfur in organic matter have not been extensively employed in large part because there has been no direct route to the analysis of 34S in individual organic compounds. To remedy this, we have developed a highly sensitive and robust method for the analysis of 34S in individual organic compounds by coupled gas chromatography (GC) and multicollector inductively-coupled plasma mass spectrometry (ICP-MS). Isobaric interference from O2+ is minimized by employing dry plasma conditions, and is cleanly resolved at all masses using medium resolution on the Thermo Neptune ICP-MS. Correction for mass bias is accomplished using standard-sample bracketing with peaks of SF6 reference gas. The precision of measured δ34S values approaches 0.1‰ for analytes containing >40 pmol S, and is better than 0.5‰ for those containing as little as 6 pmol S. External accuracy is better than 0.3‰. Integrating only the center of chromatographic peaks, rather than the entire peak, offers significant gain in precision and chromatographic resolution with minimal effect on accuracy, but requires further study for verification as a routine method. Coelution of organic compounds that do not contain S can cause degraded analytical precision and accuracy. As a demonstration of the potential for this new method, we will present data from 3 sample types: individual organosulfur compounds from crude oil, dimethyl sulfide from seawater, and trace H2S from bacterial culture headspace.

  16. Increased biogenic volatile organic compounds emission in Beijing

    NASA Astrophysics Data System (ADS)

    Wang, H.; Liu, H.; Wu, Q.

    2017-12-01

    Beijing is suffering the severe ozone pollution during the summer period and reliable biogenic volatile organic compounds (BVOCs) emission inventories would help to understand the local ozone pollution. According to the National Forest Resource Survey (NFRS), the forest coverage rate rises from 20.56% to 35.84% during 1998-2013 in Beijing. In this study, we recalculated local BVOC inventory in Beijing based on the latest MEGAN v2.1 model and satellite products. We adopted three independent leaf area index (LAI) products and three independent land cover (LC) products and designed five experiments, E1-E5, to test the sensitivity and uncertainty of local BVOC inventory. According to the estimation from the model, we conclude that: (1) the total amount of BVOCs is about 73.99 98.88 Gg. The estimated annual amount of isoprene, monoterpene, sesquiterpene and other VOC kinds are 38.79 50.93 Gg, 8.39 10.95 Gg, 1.04 1.49 Gg and 25.77 35.64 Gg, respectively. (2) Indicated by results of baseline experiment (E1), the proportions of isoprene, monoterpene, sesquiterpene and other VOCs are 52.57 %, 11.09 %, 1.39 % and 34.95%. (3) The variance of GEOV2 and GLASS LAI products only lead to 1% difference of total BVOC emissions. (4) The difference of PFTs affects the spatial distribution and emission density. The E4 with MODIS land cover leads to about 5.0% decline of BVOC compared with the E1 because of uneven meteorological conditions, e.g. DSW. The CCI-LC leads to a sharp decline of total BVOC emissions with percentage of 25.95%, which is owing to the relative low cover percentage of forest. (5) The broadleaf trees, as the dominant contributor, account for the 68.25% total annual BVOCs in Beijing in 2013. For the specific species, broadleaf trees contribute 94.52% of isoprene, 53.30% of monoterpene, 53.78% of sesquiterpene and 34.06% of other VOCs. (6) The estimated emission of BVOC in this study is much higher than the earlier estimation, and the development of forest area as

  17. Soil organic matter stability as indicated by compound-specific radiocarbon analyses

    NASA Astrophysics Data System (ADS)

    van der Voort, Tessa Sophia; Zell, Claudia; Hagedorn, Frank; McIntyre, Cameron; Eglinton, Timothy Ian

    2017-04-01

    Carbon storage in soils is increasingly recognized as a key ecosystem function, and molecular-level analyses could be a valuable potential indicator of this storage potential. In this framework, radiocarbon constitutes a powerful tool for unraveling soil carbon dynamics on both decadal as well as centennial and millennial timescales. In this study, we look at the radiocarbon signature of specific compounds (fatty acids and n-alkanes) in two forested ecosystems (temperate and pre-alpine) with the aim of attaining a better understanding of soil organic carbon stability on a molecular level. Radiocarbon dating of the fatty acids and n-alkanes has been coupled to abundance data of these compounds and additionally lignin phenols. We hypothesize that potentially, these long-chain apolar compounds could be a representative indicator of the mineral-bound soil organic carbon pool. These well-studied sites are part of the Long-Term Forest Ecosystem Research (LWF) program of the Swiss Federal Institute for Forest, Snow and Landscape research (WSL). Therefore, a wide suite of ancillary climatic and textural data is available for these sites. Initial results show a wide range of ages in the specific compounds which constitute a much larger range than the ages indicated by the density fractions done on the same samples. Overall, this study explores the use of molecular-level indicators to study soil organic matter dynamics, which could help assess the overall potential vulnerability of soil carbon in various ecosystems.

  18. How to examine soil sorption of ionizable organic compounds and avoid varying pH?

    NASA Astrophysics Data System (ADS)

    Borisover, Mikhail

    2017-04-01

    Multiple natural and anthropogenic organic compounds including new and emerging pollutants undergo ionization in aqueous solutions, and their sorption by soils and sediments is contributed by presence of both molecular and ionized species. Better understanding of environmental fate of organic chemicals requires taking into account interactions of molecular and ionized species with environmental sorbents. A "standard" (and undoubtedly important) procedure for differentiating contributions of molecular and ionized species into the overall soil sorption of an organic compound involves varying pH of solution in batch sorption experiments. However, varying pH is (1) often not possible, without destroying a sorbent, e.g., due to the buffer capacity of soils containing carbonates, (2) difficult for further interpretation, since it changes not only the ionization status of a solute in a solution but also the sorbent structure, e.g., a conformation of organic matter, and/or ionization of surface functional groups, (3) making difficult (or even impossible) to explicitly evaluate the role of dissolved species-bulk water interactions, directly affecting the affinity of a sorbate to distribute between water and a sorbent. Indeed, both molecular and ionized species undergo interactions with the solvent bulk and, at least in the case of the ionized ones, there was no a simple way to quantify organic ion-water interactions and their role in organic ion distribution between soil and water phases. This paper presents a "counter-intuitive" approach to examine sorption interactions of an ionizable compound, without experimenting with varied pH. The approach is based on an idea of replacing an initial state in sorption transfer of an ionizable compound from the solvent bulk to a solvated (hydrated) sorbed state: a traditional coefficient describing distribution of a partially ionized compound between a hydrated sorbent and a co-equilibrated aqueous phase is converted to the coefficient

  19. Bibliography on contaminants and solubility of organic compounds in oxygen

    NASA Technical Reports Server (NTRS)

    Ordin, P. M. (Compiler)

    1975-01-01

    A compilation of a number of document citations is presented which contains information on contaminants in oxygen. Topics covered include contaminants and solubility of organic compounds in oxygen, reaction characteristics of organic compounds with oxygen, and sampling and detection limits of impurities. Each citation in the data bank contains many items of information about the document. Some of the items are title, author, abstract, corporate source, description of figures pertinent to hazards or safety, key references, and descriptors (keywords) by which the document can be retrieved. Each citation includes an evaluation of the technical contents as to being good/excellent, acceptable, or poor. The descriptors used to define the contents of the documents and subsequently used in the computerized search operations were developed for the cryogenic fluid safety by experts in the cryogenics field.

  20. Increase in volatilization of organic compounds using air sparging through addition in alcohol in a soil-water system.

    PubMed

    Chao, Huan-Ping; Hsieh, Lin-Han Chiang; Tran, Hai Nguyen

    2018-02-15

    This study developed a novel method to promote the remediation efficiency of air sparging. According to the enhanced-volatilization theory presented in this study, selected alcohols added to groundwater can highly enhance the volatilization amounts of organic compounds with high Henry's law constants. In this study, the target organic compounds consisted of n-hexane, n-heptane, benzene, toluene, 1,1,2-trichloroethane, and tetrachloroethene. n-pentanol, n-hexanol, and n-heptanol were used to examine the changes in the volatilization amounts of organic compounds in the given period. Two types of soils with high and low organic matter were applied to evaluate the transport of organic compounds in the soil-water system. The volatilization amounts of the organic compounds increased with increasing alcohol concentrations. The volatilization amounts of the test organic compounds exhibited a decreasing order: n-heptanol>n-hexanol>n-pentanol. When 10mg/L n-heptanol was added to the system, the maximum volatilization enhancement rate was 18-fold higher than that in distilled water. Samples of soil with high organic matter might reduce the volatilization amounts by a factor of 5-10. In the present study, the optimal removal efficiency for aromatic compounds was approximately 98%. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Significance of investigating allelopathic interactions of marine organisms in the discovery and development of cytotoxic compounds.

    PubMed

    Singh, Anshika; Thakur, Narsinh L

    2016-01-05

    Marine sessile organisms often inhabit rocky substrata, which are crowded by other sessile organisms. They acquire living space via growth interactions and/or by allelopathy. They are known to secrete toxic compounds having multiple roles. These compounds have been explored for their possible applications in cancer chemotherapy, because of their ability to kill rapidly dividing cells of competitor organisms. As compared to the therapeutic applications of these compounds, their possible ecological role in competition for space has received little attention. To select the potential candidate organisms for the isolation of lead cytotoxic molecules, it is important to understand their chemical ecology with special emphasis on their allelopathic interactions with their competitors. Knowledge of the ecological role of allelopathic compounds will contribute significantly to an understanding of their natural variability and help us to plan effective and sustainable wild harvests to obtain novel cytotoxic chemicals. This review highlights the significance of studying allelopathic interactions of marine invertebrates in the discovery of cytotoxic compounds, by selecting sponge as a model organism. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Anthropogenic organic compounds in source water of nine community water systems that withdraw from streams, 2002-05

    USGS Publications Warehouse

    Kingsbury, James A.; Delzer, Gregory C.; Hopple, Jessica A.

    2008-01-01

    compound. Samples typically contained mixtures of two or more compounds. The total number of compounds and their total concentration in samples generally increased with the amount of urban and agricultural land use in a watershed. Annual mean concentrations of all compounds were less than human-health benchmarks. Single-sample concentrations of anthropogenic organic compounds in source water generally were less than 0.1 microgram per liter and less than established human-health benchmarks. Human-health benchmarks used for comparison were U.S. Environmental Protection Agency (USEPA) Maximum Contaminant Levels (MCLs) for regulated compounds and U.S. Geological Survey Health-Based Screening Levels for unregulated compounds. About one-half of all detected compounds do not have human-health benchmarks or adequate toxicity information for evaluating results in a human-health context. During a second sampling phase (2004-05), source water and finished water (water that has passed through all the treatment processes but prior to distribution) were sampled at eight of the nine community water systems. Water-treatment processes differ among the systems. Specifically, treatment at five of the systems is conventional, typically including steps of coagulation, flocculation, sedimentation, filtration, and disinfection. One water system uses slow sand filtration and disinfection, a second system uses ozone as a preliminary treatment step to conventional treatment, and a third system is a direct filtration treatment plant that uses many of the steps employed in conventional treatment. Most of these treatment steps are not designed specifically to remove the compounds monitored in this study. About two-thirds of the compounds detected commonly in source water were detected at similar frequencies in finished water. Although the water-treatment steps differ somewhat among the eight water systems, the amount of change in concentration of the compounds from source- to finish

  3. Examining the association of DDX compounds to sedimentary organic matter

    NASA Astrophysics Data System (ADS)

    Weathers, N.; Rowlett, K.; Geng, Z.; Morrison, A.; White, H. K.

    2016-02-01

    The association of hydrophobic organic contaminants (HOCs) with sedimentary organic matter (OM) influences their mobility and bioavailability in the environment. Determining whether these associations result from mechanisms such as sorption, chemical binding or encapsulation is critical for predicting their long-term fate. The pesticide DDT (dichlorodiphenyltrichloroethane) has been previously observed to form bound residues with sedimentary OM although the mechanisms of this association are yet to be fully explored. DDT, which was sprayed ubiquitously in the 1950s and early 1960s, can still be found in the environment today along with its three major metabolites, DDE, DDD and DDMU (collectively known as DDX compounds), and therefore presents a unique opportunity to further explore its long-term associations with OM. To this end, a sediment core from a salt marsh in Dover, Delaware known to contain DDX compounds was collected. A maximum concentration of DDX compounds was found at sediment depths corresponding to the time of the widespread usage of DDT. An initial solvent extraction with toluene provided data on the loosely associated DDX fraction followed by subsequent treatments with sulfuric acid and saponification to release DDX that was encapsulated or bound to the sedimentary matrix. Determining the physical disposition of DDX compounds that persist in sediments for several decades is integral to determining the extent to which they are mobile, bioavailable or sequestered in the marsh.

  4. Determination of organic compounds in water using ultraviolet LED

    NASA Astrophysics Data System (ADS)

    Kim, Chihoon; Ji, Taeksoo; Eom, Joo Beom

    2018-04-01

    This paper describes a method of detecting organic compounds in water using an ultraviolet LED (280 nm) spectroscopy system and a photodetector. The LED spectroscopy system showed a high correlation between the concentration of the prepared potassium hydrogen phthalate and that calculated by multiple linear regression, indicating an adjusted coefficient of determination ranging from 0.953-0.993. In addition, a comparison between the performance of the spectroscopy system and the total organic carbon analyzer indicated that the difference in concentration was small. Based on the close correlation between the spectroscopy and photodetector absorbance values, organic measurement with a photodetector could be configured for monitoring.

  5. Airborne concentrations of volatile organic compounds in neonatal incubators.

    PubMed

    Prazad, P; Cortes, D R; Puppala, B L; Donovan, R; Kumar, S; Gulati, A

    2008-08-01

    To identify and quantify airborne volatile organic compounds (VOCs) inside neonatal incubators during various modes of operation within the neonatal intensive care unit (NICU) environment. Air samples were taken from 10 unoccupied incubators in four operational settings along with ambient air samples using air sampling canisters. The samples were analyzed following EPA TO-15 using a Tekmar AutoCan interfaced to Agilent 6890 Gas Chromatograph with a 5973 Mass Spectrometer calibrated for 60 EPA TO-15 method target compounds. Non-target compounds were tentatively identified using mass spectral interpretation and with a mass spectral library created by National Institute for Standards and Technology. Two non-target compounds, 2-heptanone and n-butyl acetate, were found at elevated concentrations inside the incubators compared with ambient room air samples. Increase in temperature and addition of humidity produced further increased concentrations of these compounds. Their identities were verified by mass spectra and relative retention times using authentic standards. They were quantified using vinyl acetate and 2-hexanone as surrogate standards. The emission pattern of these two compounds and background measurements indicate that they originate inside the incubator. There is evidence that exposure to some VOCs may adversely impact the fetal and developing infants' health. Currently, as there is no definitive information available on the effects of acute or chronic low-level exposure to these compounds in neonates, future studies evaluating the health effects of neonatal exposure to these VOCs are needed.

  6. Analysis of volatile organic compounds of ‘Fuji’ apples following electron beam irradiation and storage

    NASA Astrophysics Data System (ADS)

    Song, Hyun-Pa; Shim, Sung-Lye; Lee, Sun-Im; Kim, Dong-Ho; Kwon, Joong-Ho; Kim, Kyong-Su

    2012-08-01

    The volatile organic compounds of non-irradiated and electron-beam irradiated 'Fuji' apples (Malus domestica Borkh.) at 0, 0.5, and 1 kGy were isolated through simultaneous distillation extractions and analyzed using gas chromatograph-mass spectrometry. A total of 53 volatile organic compounds were characterized in 0 and 1 kGy irradiated samples, whereas two more compounds related to ketone and terpenoid group were identified in 0.5 kGy irradiated samples. The contents of volatile compounds were 24.33, 36.49, and 35.28 mg/kg in 0, 0.5, and 1 kGy irradiated samples, respectively. The major compounds identified were butanol, hexanal, [E]-2-hexenal, and hexanol in all samples. The relative content of alcohol increased after 30 days of storage in all samples, whereas that of aldehyde decreased. Although the contents of some volatile compounds were changed by electron-beam irradiation, the total yield and major flavor compounds of irradiated 'Fuji' apples were similar to, or even greater than, those of the control. Therefore, the application of e-beam irradiation if required for microbial decontamination of 'Fuji' apples is an acceptable method as it does not bring about any major quantitative changes of volatile organic compounds.

  7. Global simulation of aromatic volatile organic compounds in the atmosphere

    NASA Astrophysics Data System (ADS)

    Cabrera Perez, David; Taraborrelli, Domenico; Pozzer, Andrea

    2015-04-01

    Among the large number of chemical compounds in the atmosphere, the organic group plays a key role in the tropospheric chemistry. Specifically the subgroup called aromatics is of great interest. Aromatics are the predominant trace gases in urban areas due to high emissions, primarily by vehicle exhausts and fuel evaporation. They are also present in areas where biofuel is used (i.e residential wood burning). Emissions of aromatic compounds are a substantial fraction of the total emissions of the volatile organic compounds (VOC). Impact of aromatics on human health is very important, as they do not only contribute to the ozone formation in the urban environment, but they are also highly toxic themselves, especially in the case of benzene which is able to trigger a range of illness under long exposure, and of nitro-phenols which cause detrimental for humans and vegetation even at very low concentrations. The aim of this work is to assess the atmospheric impacts of aromatic compounds on the global scale. The main goals are: lifetime and budget estimation, mixing ratios distribution, net effect on ozone production and OH loss for the most emitted aromatic compounds (benzene, toluene, xylenes, ethylbenzene, styrene and trimethylbenzenes). For this purpose, we use the numerical chemistry and climate simulation ECHAM/MESSy Atmospheric Chemistry (EMAC) model to build the global atmospheric budget for the most emitted and predominant aromatic compounds in the atmosphere. A set of emissions was prepared in order to include biomass burning, vegetation and anthropogenic sources of aromatics into the model. A chemical mechanism based on the Master Chemical Mechanism (MCM) was developed to describe the chemical oxidation in the gas phase of these aromatic compounds. MCM have been reduced in terms of number of chemical equation and species in order to make it affordable in a 3D model. Additionally other features have been added, for instance the production of HONO via ortho

  8. Volatile organic compounds and particulates as components of diesel engine exhaust gas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schulz, H.; Bandeira de Melo, G.; Ousmanov, F.

    1999-07-01

    Volatile organic compounds (VOC) and soot particles have been determined in a Diesel`s exhaust gas. A new sampling method allowed the measurement of emissions of organic compounds (C{sub 1} to C{sub 20}) in a gas chromatogram at a detection limit of ca. 0.2 mg/m{sup 3}. Particles were collected with a filter bed of ceramic particles and characterized by temperature programmed desorption (TPD) and oxidation (TPO). Engine runs were always performed at a fixed and constant air to fuel equivalence ratio ({lambda}) and with a constant volumetric efficiency, because these parameters strongly influenced the emissions in terms of both composition andmore » order of magnitude. The effective combustion temperature again strongly governed the nature of the emissions. Model fuels, composed of individual paraffins and aromatics and additions of sulfur compounds and an organic nitrate (for cetane number enhancement) were used. The results contribute to the understanding of the origin of specific emissions from Diesel engines. These newly developed methods are recommended for further application.« less

  9. Volatile organic compound emissions from elephant grass and bamboo cultivars used as potential bioethanol crop

    NASA Astrophysics Data System (ADS)

    Crespo, E.; Graus, M.; Gilman, J. B.; Lerner, B. M.; Fall, R.; Harren, F. J. M.; Warneke, C.

    2013-02-01

    Volatile organic compound (VOC) emissions from elephant grass (Miscanthus gigantus) and black bamboo (Phyllostachys nigra) were measured online in semi-field chamber and plant enclosure experiments during growth and harvest using proton-transfer reaction mass spectrometry (PTR-MS), proton-transfer reaction ion-trap mass spectrometry (PIT-MS) and gas chromatography-mass spectrometry (GC-MS). Both cultivars are being considered for second-generation biofuel production. Before this study, no information was available on their yearly VOC emissions. This exploratory investigation shows that black bamboo is a strong isoprene emitter (daytime 28,516 ng gdwt-1 h-1) and has larger VOC emissions, especially for wound compounds from the hexanal and hexenal families, than elephant grass. Daytime emissions of methanol, acetaldehyde, acetone + propanal and acetic acid of black bamboo were 618, 249, 351, and 1034 ng gdwt-1 h-1, respectively. In addition, it is observed that elephant grass VOC emissions after harvesting strongly depend on the seasonal stage. Not taking VOC emission variations throughout the season for annual and perennial species into account, may lead to an overestimation of the impact on local air quality in dry periods. In addition, our data suggest that the use of perennial grasses for extensive growing for biofuel production have lower emissions than woody species, which might be important for regional atmospheric chemistry.

  10. Group extraction of organic compounds present in liquid samples

    NASA Technical Reports Server (NTRS)

    Jahnsen, Vilhelm J. (Inventor)

    1976-01-01

    An extraction device is disclosed comprising a tube containing a substantially inert, chemically non-reactive packing material with a large surface area to volume ratio. A sample which consists of organic compounds dissolved in a liquid, is introduced into the tube. As the sample passes through the packing material it spreads over the material's large surface area to form a thin liquid film which is held on the packing material in a stationary state. A particular group or family of compounds is extractable from the sample by passing a particular solvent system consisting of a solvent and selected reagents through the packing material. The reagents cause optimum conditions to exist for the compounds of the particular family to pass through the phase boundary between the sample liquid and the solvent of the solvent system. Thus, the compounds of the particular family are separated from the sample liquid and become dissolved in the solvent of the solvent system. The particular family of compounds dissolved in the solvent, representing an extract, exits the tube together with the solvent through the tube's nozzle, while the rest of the sample remains on the packing material in a stationary state. Subsequently, a different solvent system may be passed through the packing material to extract another family of compounds from the remaining sample on the packing material.

  11. Preparation and Characterization of Organic-Inorganic Hybrid Macrocyclic Compounds: Cyclic Ladder-like Polyphenylsilsesquioxanes.

    PubMed

    Zhang, Wenchao; Wang, Xiaoxia; Wu, Yiwei; Qi, Zhi; Yang, Rongjie

    2018-04-02

    Organic-inorganic hybrid macrocyclic compounds, cyclic polyphenylsilsesquioxanes (cyc-PSQs), have been synthesized through hydrolysis and condensation reactions of phenyltrichlorosilane. Structural characterization has revealed that cyc-PSQs consist of a closed-ring double-chain siloxane inorganic backbone bearing organic phenyl groups. The cyc-PSQ molecules have been simulated and structurally optimized using the Forcite tool as implemented in Materials Studio. Structurally optimized cyc-PSQs are highly symmetrical and regular with high stereoregularity, consistent with the dimensions of their experimentally derived structures. Thermogravimetric analysis showed that these macrocyclic compounds have excellent thermal stability. In addition to these perfectly structured compounds, macrocyclic compounds with the same ring ladder structure but bearing an additional Si-OH group, cyc-PSQs-OH, have also been synthesized. A possible mechanism for the formation of the closed-ring molecular structures of cyc-PSQs and cyc-PSQs-OH is proposed.

  12. Simulation of the interannual variations of biogenic emissions of volatile organic compounds in China: Impacts on tropospheric ozone and secondary organic aerosol

    NASA Astrophysics Data System (ADS)

    Fu, Y.; Liao, H.

    2012-12-01

    We use the MEGAN (Model of emissions of Gases and Aerosols from Nature) module embedded within the global three-dimensional Goddard Earth Observing System chemical transport model (GEOS-Chem) to simulate the interannual variations in biogenic volatile organic compound (BVOC) emissions and concentrations of ozone and secondary organic aerosols (SOA) in China over years 2001-2006. To have better representation of biogenic emissions, we have updated in the model the land cover and leaf area index in China using Moderate Resolution Imaging Spectroradiometer (MODIS) satellite measurements, and we have developed a new classification of vegetation with 21 plant functional types. Estimated annual BVOC emission in China averaged over 2001-2006 is 18.85 Tg C yr-1, in which emissions of isoprene, monoterpenes, and other reactive volatile organic compounds account for 50.9%, 15.0%, and 34.1%, respectively. The simulated BVOC emissions in China have large interannual variations. The values of regionally averaged absolute percent departure from the mean (APDM) of isoprene emissions are in the range of 21-42% in January and 15-28% in July. The APDM values of monoterpene emissions are 14-32% in January and 10-21% in July, which are generally smaller than those of isoprene emissions. Model results indicate that the interannual variations in isoprene emissions are more dependent on variations in meteorological fields, whereas the interannual variations in monoterpene emissions are more sensitive to changes in vegetation parameters. With fixed anthropogenic emissions, as a result of the variations in both meteorological parameters and vegetation, simulated O3 concentrations show interannual variations of 0.8-5 ppbv (or largest APDM values of 4-15%), and simulated SOA shows APDM values of 5-15% in southwestern China in January as well as 10-25% in southeastern and 20-35% in northeastern China in July. On a regional mean basis, the interannual variations in BVOCs alone can lead to 2

  13. Simulation of the interannual variations of biogenic emissions of volatile organic compounds in China: Impacts on tropospheric ozone and secondary organic aerosol

    NASA Astrophysics Data System (ADS)

    Fu, Yu; Liao, Hong

    2012-11-01

    We use the MEGAN (Model of emissions of Gases and Aerosols from Nature) module embedded within the global three-dimensional Goddard Earth Observing System chemical transport model (GEOS-Chem) to simulate the interannual variations in biogenic volatile organic compound (BVOC) emissions and concentrations of ozone and secondary organic aerosols (SOA) in China over years 2001-2006. To have better representation of biogenic emissions, we have updated in the model the land cover and leaf area index in China using Moderate Resolution Imaging Spectroradiometer (MODIS) satellite measurements, and we have developed a new classification of vegetation with 21 plant functional types. Estimated annual BVOC emission in China averaged over 2001-2006 is 18.85 Tg C yr-1, in which emissions of isoprene, monoterpenes, and other reactive volatile organic compounds account for 50.9%, 15.0%, and 34.1%, respectively. The simulated BVOC emissions in China have large interannual variations. The values of regionally averaged absolute percent departure from the mean (APDM) of isoprene emissions are in the range of 21-42% in January and 15-28% in July. The APDM values of monoterpene emissions are 14-32% in January and 10-21% in July, which are generally smaller than those of isoprene emissions. Model results indicate that the interannual variations in isoprene emissions are more dependent on variations in meteorological fields, whereas the interannual variations in monoterpene emissions are more sensitive to changes in vegetation parameters. With fixed anthropogenic emissions, as a result of the variations in both meteorological parameters and vegetation, simulated O3 concentrations show interannual variations of 0.8-5 ppbv (or largest APDM values of 4-15%), and simulated SOA shows APDM values of 5-15% in southwestern China in January as well as 10-25% in southeastern and 20-35% in northeastern China in July. On a regional mean basis, the interannual variations in BVOCs alone can lead to 2

  14. Uptake of Small Organic Compounds by Sulfuric Acid Aerosols: Dissolution and Reaction

    NASA Technical Reports Server (NTRS)

    Iraci, L. T.; Michelsen, R. R.; Ashbourn, S. F. M.; Staton, S. J. R.

    2003-01-01

    To assess the role of oxygenated volatile organic compounds in the upper troposphere and lower stratosphere, the interactions of a series of small organic compounds with low-temperature aqueous sulfuric acid will be evaluated. The total amount of organic material which may be taken up from the gas phase by dissolution, surface layer formation, and reaction during the particle lifetime will be quantified. Our current results for acetaldehyde uptake on 40 - 80 wt% sulfuric acid solutions will be compared to those of methanol, formaldehyde, and acetone to investigate the relationships between chemical functionality and heterogeneous activity. Where possible, equilibrium uptake will be ascribed to component pathways (hydration, protonation, etc.) to facilitate evaluation of other species not yet studied in low temperature aqueous sulfuric acid.

  15. Sorption characteristics of organic compounds on hexadecyltrimethylammonium-smectite

    USGS Publications Warehouse

    Boyd, Stephen A.; Mortland, Max M.; Chiou, Cary T.

    1988-01-01

    When hexadedyltrimethylammonium (HDTMA) ion is exchanged for metal cations like calcium in smectite, the sorptive properties of the clay are greatly modified. The resultant HDTMA-smectite complex behaves as a dual sorbent, in the sorption of organic compounds, in which the mineral fraction functions as a solid adsorbent and the organic (HDTMA) phase as a partition medium. Capacities of mineral adsorption and partition uptake by HDTMA in the HDTMA-smectites are illustrated by sorption of benzene, trichloroethene (TCE), and water as vapors on the dry sample and by sorption of benzene and TCE from water. The exchanged HDTMA in clay is found to be a much more powerful partition medium than ordinary soil organic matter in the uptake of benzene and TCE. Based on this finding, HDTMA-smectite appears to be an effective sorbent for removing organic contaminants from water. It is suggested that such sorptive organo-clay complexes could be used to enhance the containment capabilities of clay landfill liners and bentonite slurry walls.

  16. A Century of Professional Organization Influence: Findings from Content Analyses of MVTTEC Annual Meetings

    ERIC Educational Resources Information Center

    Wells, John

    2015-01-01

    Investigating the content presented at annual national conferences is regarded by many as a valid means for revealing patterns within a given professional organization concerning their interests, issues, concerns, priorities, and research foci, which collectively present an opportunity to provide future direction for the organization. As a result,…

  17. 78 FR 53029 - Air Quality: Revision to Definition of Volatile Organic Compounds-Exclusion of trans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-28

    ... Air Quality: Revision to Definition of Volatile Organic Compounds--Exclusion of trans 1-chloro-3,3,3.... SUMMARY: The EPA is taking final action to revise the regulatory definition of volatile organic compounds..., June 16, 2010), and as a solvent for metals, electronics, and precision cleaning and in adhesives...

  18. A Review of the Tissue Residue Approach for Organic and Organometallic Compounds in Aquatic Organisms

    EPA Science Inventory

    This paper reviews the tissue residue approach (TRA) for toxicity assessment as it applies to organic chemicals and some organometallic compounds (tin, mercury, and lead). Specific emphasis was placed on evaluating key factors that influence interpretation of critical body resid...

  19. Uncertainty in aerosol hygroscopicity resulting from semi-volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Goulden, Olivia; Crooks, Matthew; Connolly, Paul

    2018-01-01

    We present a novel method of exploring the effect of uncertainties in aerosol properties on cloud droplet number using existing cloud droplet activation parameterisations. Aerosol properties of a single involatile particle mode are randomly sampled within an uncertainty range and resulting maximum supersaturations and critical diameters calculated using the cloud droplet activation scheme. Hygroscopicity parameters are subsequently derived and the values of the mean and uncertainty are found to be comparable to experimental observations. A recently proposed cloud droplet activation scheme that includes the effects of co-condensation of semi-volatile organic compounds (SVOCs) onto a single lognormal mode of involatile particles is also considered. In addition to the uncertainties associated with the involatile particles, concentrations, volatility distributions and chemical composition of the SVOCs are randomly sampled and hygroscopicity parameters are derived using the cloud droplet activation scheme. The inclusion of SVOCs is found to have a significant effect on the hygroscopicity and contributes a large uncertainty. For non-volatile particles that are effective cloud condensation nuclei, the co-condensation of SVOCs reduces their actual hygroscopicity by approximately 25 %. A new concept of an effective hygroscopicity parameter is introduced that can computationally efficiently simulate the effect of SVOCs on cloud droplet number concentration without direct modelling of the organic compounds. These effective hygroscopicities can be as much as a factor of 2 higher than those of the non-volatile particles onto which the volatile organic compounds condense.

  20. Occurrence of Organic Wastewater Compounds in Selected Surface-Water Supplies, Triangle Area of North Carolina, 2002-2005

    USGS Publications Warehouse

    Giorgino, M.J.; Rasmussen, R.B.; Pfeifle, C.M .

    2007-01-01

    Selected organic wastewater compounds, such as household, industrial, and agricultural-use compounds, sterols, pharmaceuticals, and antibiotics, were measured at eight sites classified as drinking-water supplies in the Triangle Area of North Carolina. From October 2002 through July 2005, seven of the sites were sampled twice, and one site was sampled 28 times, for a total of 42 sets of environmental samples. Samples were analyzed for as many as 126 compounds using three laboratory analytical methods. These methods were developed by the U.S. Geological Survey to detect low levels (generally less than or equal to 1.0 microgram per liter) of the target compounds in filtered water. Because analyses were conducted on filtered samples, the results presented in this report may not reflect the total concentration of organic wastewater compounds in the waters that were sampled. Various quality-control samples were used to quality assure the results in terms of method performance and possible laboratory or field contamination. Of the 108 organic wastewater compounds that met method performance criteria, 24 were detected in at least one sample during the study. These 24 compounds included 3 pharmaceutical compounds, 6 fire retardants and plasticizers, 3 antibiotics, 3 pesticides, 6 fragrances and flavorants, 1 disinfectant, and 2 miscellaneous-use compounds, all of which likely originated from a variety of domestic, industrial, and agricultural sources. The 10 most frequently detected compounds included acetyl-hexamethyl tetrahydronaphthalene and hexahydro-hexamethyl cyclopentabenzopyran (synthetic musks that are widely used in personal-care products and are known endocrine disruptors); tri(2-chloroethyl) phosphate, tri(dichloroisopropyl) phosphate, and tributyl phosphate (fire retardants); metolachlor (herbicide); caffeine (nonprescription stimulant); cotinine (metabolite of nicotine); acetaminophen (nonprescription analgesic); and sulfamethoxazole (prescription antibiotic

  1. Measurement of volatile organic compounds inside automobiles.

    PubMed

    Fedoruk, Marion J; Kerger, Brent D

    2003-01-01

    The objective of the current study was to evaluate the types and concentrations of volatile organic compounds (VOCs) in the passenger cabin of selected sedan automobiles under static (parked, unventilated) and specified conditions of operation (i.e., driving the vehicle using air conditioning alone, vent mode alone, or driver's window half open). Data were collected on five different passenger sedan vehicles from three major automobile manufacturers. Airborne concentrations were assessed using 90-min time-weighted average (TWA) samples under U.S. Environmental Protection Agency (USEPA) Method IP-1B to assess individual VOC compounds and total VOCs (TVOCs) calibrated to toluene. Static vehicle testing demonstrated TVOC levels of approximately 400-800 microg/m(3) at warm interior vehicle temperatures (approximately 80 degrees F), whereas TVOCs at least fivefold higher were observed under extreme heat conditions (e.g., up to 145 degrees F). The profile of most prevalent individual VOC compounds varied considerably according to vehicle brand, age, and interior temperature tested, with predominant compounds including styrene, toluene, and 8- to 12-carbon VOCs. TVOC levels under varied operating conditions (and ventilation) were generally four- to eightfold lower (at approximately 50-160 microg/m(3)) than the static vehicle measurements under warm conditions, with the lowest measured levels generally observed in the trials with the driver's window half open. These data indicate that while relatively high concentrations of certain VOCs can be measured inside static vehicles under extreme heat conditions, normal modes of operation rapidly reduce the inside-vehicle VOC concentrations even when the air conditioning is set on recirculation mode.

  2. Salt lakes of Western Australia - Natural abiotic formation of volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Krause, T.; Studenroth, S.; Mulder, I.; Tubbesing, C.; Kotte, K.; Ofner, J.; Junkermann, W.; Schöler, H. F.

    2012-04-01

    Western Australia is a semi-/arid region that is heavily influenced by global climate change and agricultural land use. The area is known for its many ephemeral saline and hypersaline lakes with a wide range of hydrogeochemical parameters that have gradually changed over the last fifty years. Historically, the region was covered by eucalyptus trees and shrubs, but was cleared mainly within 10 years after WWII to make room for wheat and live stock. After the clearance of the deep rooted native plants the groundwater started to rise, bringing increased amounts of dissolved salts and minerals to the surface and discharging them into streams and lakes. Thus most of Western Australia is influenced by secondary salinisation (soil salting) [1]. Another problem is that the discharged minerals affect the pH of ground and surface water, which ranges from acidic to slightly basic. During the 2011 campaign surface water was measured with a pH between 2.5 and 7.1. Another phenomenon in Western Australia is the decrease of rainfall over the last decades assumed to be linked to the secondary salinisation. The rising saline and mineral rich groundwater increases the biotical and abiotical activity of the salt lakes. Halogenated and non-halogenated volatile organic compounds emitted from those lakes undergo fast oxidation and chemical reactions to form small particles modifying cloud microphysics and thus suppressing rain events [2]. Our objective is to gain a better understanding of this extreme environment with its hypersaline acidic lakes with regard to the potential abiotic formation of volatile organic compounds and its impact on the local climate. In spring 2011 fifty-three sediment samples from ten salt lakes in the Lake King region where taken, freeze-dried and ground. In order to simulate the abiotic formation of volatile organic compounds the soil samples were resuspended with water in gas-tight headspace vials. The headspace was measured using a purge and trap GC

  3. User’s guide to the collection and analysis of tree cores to assess the distribution of subsurface volatile organic compounds

    USGS Publications Warehouse

    Vroblesky, Don A.

    2008-01-01

    Analysis of the volatile organic compound content of tree cores is an inexpensive, rapid, simple approach to examining the distribution of subsurface volatile organic compound contaminants. The method has been shown to detect several volatile petroleum hydrocarbons and chlorinated aliphatic compounds associated with vapor intrusion and ground-water contamination. Tree cores, which are approximately 3 inches long, are obtained by using an increment borer. The cores are placed in vials and sealed. After a period of equilibration, the cores can be analyzed by headspace analysis gas chromatography. Because the roots are exposed to volatile organic compound contamination in the unsaturated zone or shallow ground water, the volatile organic compound concentrations in the tree cores are an indication of the presence of subsurface volatile organic compound contamination. Thus, tree coring can be used to detect and map subsurface volatile organic compound contamination. For comparison of tree-core data at a particular site, it is important to maintain consistent methods for all aspects of tree-core collection, handling, and analysis. Factors affecting the volatile organic compound concentrations in tree cores include the type of volatile organic compound, the tree species, the rooting depth, ground-water chemistry, the depth to the contaminated horizon, concentration differences around the trunk related to variations in the distribution of subsurface volatile organic compounds, concentration differences with depth of coring related to volatilization loss through the bark and possibly other unknown factors, dilution by rain, seasonal influences, sorption, vapor-exchange rates, and within-tree volatile organic compound degradation.

  4. Nutrients, organic compounds, and mercury in the Meduxnekeag River watershed, Maine, 2003

    USGS Publications Warehouse

    Schalk, Charles W.; Tornes, Lan

    2005-01-01

    In 2003, the U.S. Geological Survey, in cooperation with the Houlton Band of Maliseet Indians, sampled streambed sediments and surface water of the Meduxnekeag River watershed in northeastern Maine under various hydrologic conditions for nutrients, hydrophobic organic compounds, and mercury. Nutrients were sampled to address concerns related to summer algal blooms, and organic compounds and mercury were sampled to address concerns about regional depositional patterns and overall watershed quality. In most surface-water samples, phosphorus was not detected or was detected at concentrations below the minimum reporting limit. Nitrate and organic nitrogen were detected in every surface-water sample for which they were analyzed; the highest concentration of total nitrogen was 0.75 milligrams per liter during low flow. Instantaneous nitrogen loads and yields were calculated at four stations for two sampling events. These data indicate that the part of the watershed that includes Houlton, its wastewater-treatment plant, and four small urban brooks may have contributed high concentrations of nitrate to Meduxnekeag River during the high flows on April 23-24 and high concentrations of both organic and nitrate nitrogen on June 2-3. Mercury was detected in all three bed-sediment samples for which it was analyzed; concentrations were similar to those reported from regional studies. Notable organic compounds detected in bed sediments included p,p'-DDE and p,p'-DDT (pesticides of the DDT family) and several polycyclic aromatic hydrocarbons. Polychlorinated biphenyls (PCBs) and phthalates were not detected in any sample, whereas p-cresol was the only phenolic compound detected. Phosphorus was detected at concentrations below 700 milligrams per kilogram in each bed-sediment sample for which it was analyzed. Data were insufficient to establish whether the lack of large algal blooms in 2003 was related to low concentrations of phosphorus.

  5. Catalytic Hydrogenation of Organic Compounds without H2 Supply: An Electrochemical System

    ERIC Educational Resources Information Center

    Navarro, Daniela Maria do Amaral Ferraz; Navarro, Marcelo

    2004-01-01

    An experiment developed for an undergraduate organic chemistry laboratory course that can be used to introduce the catalytic hydrogenation reaction, catalysis electrochemical principles and gas chromatography is presented. The organic compounds hydrogenated by the electrocatalytic hydrogenation (ECH) process were styrene, benzaldehyde and…

  6. Carbonaceous meteorites as a source of sugar-related organic compounds for the early Earth

    NASA Technical Reports Server (NTRS)

    Cooper, G.; Kimmich, N.; Belisle, W.; Sarinana, J.; Brabham, K.; Garrel, L.

    2001-01-01

    The much-studied Murchison meteorite is generally used as the standard reference for organic compounds in extraterrestrial material. Amino acids and other organic compounds important in contemporary biochemistry are thought to have been delivered to the early Earth by asteroids and comets, where they may have played a role in the origin of life. Polyhydroxylated compounds (polyols) such as sugars, sugar alcohols and sugar acids are vital to all known lifeforms-they are components of nucleic acids (RNA, DNA), cell membranes and also act as energy sources. But there has hitherto been no conclusive evidence for the existence of polyols in meteorites, leaving a gap in our understanding of the origins of biologically important organic compounds on Earth. Here we report that a variety of polyols are present in, and indigenous to, the Murchison and Murray meteorites in amounts comparable to amino acids. Analyses of water extracts indicate that extraterrestrial processes including photolysis and formaldehyde chemistry could account for the observed compounds. We conclude from this that polyols were present on the early Earth and therefore at least available for incorporation into the first forms of life.

  7. Volatile organic compounds associated with Plasmodium falciparum infection in vitro.

    PubMed

    Correa, Ricardo; Coronado, Lorena M; Garrido, Anette C; Durant-Archibold, Armando A; Spadafora, Carmenza

    2017-05-02

    In order to identify new ways to prevent transmission of vector-borne diseases such as malaria, efforts have been made to understand how insects are attracted to humans. Vector-host interaction studies have shown that several volatile compounds play an important role in attracting mosquitoes to human targets. A headspace solid-phase micro-extraction/gas chromatography-mass spectrometry (HSPME GC-MS) analysis of the volatile organic composition of extracellular vesicles (EVs) and supernatants of ultracentrifugation (SNUs) was carried out in Plasmodium falciparum-infected cultures with high and low parasitemias. A list of 18 volatile organic compounds (VOCs) was obtained from the EVs of both infected and uninfected RBCs with 1,2,3-Propanetriol, diacetate (diacetin) increased in the infected EVs, regardless of the parasitemia of the culture. The supernatant analysis, however, gave off 56 VOCs, with pentane 2,2,4-trimethyl being present in all the SNUs of uninfected erythrocytes but absent from the parasite-infected ones. Standing out in this study was hexanal, a reported insect attractant, which was the only VOC present in all samples from SNUs from infected erythrocytes and absent from uninfected ones, suggesting that it originates during parasite infection. The hexanal compound, reportedly a low-level component found in healthy human samples such as breath and plasma, had not been found in previous analyses of P. falciparum-infected patients or cultures. This compound has been reported as an Anopheles gambiae attractant in plants. While the compound could be produced during infection by the malaria parasite in human erythrocytes, the A. gambiae attraction could be used by the parasite as a strategy for transmission.

  8. Development of the GC-MS organic aerosol monitor (GC-MS OAM) for in-field detection of particulate organic compounds

    NASA Astrophysics Data System (ADS)

    Cropper, Paul M.; Overson, Devon K.; Cary, Robert A.; Eatough, Delbert J.; Chow, Judith C.; Hansen, Jaron C.

    2017-11-01

    Particulate matter (PM) is among the most harmful air pollutants to human health, but due to its complex chemical composition is poorly characterized. A large fraction of PM is composed of organic compounds, but these compounds are not regularly monitored due to limitations in current sampling and analysis techniques. The Organic Aerosol Monitor (GC-MS OAM) combines a collection device with thermal desorption, gas chromatography and mass spectrometry to quantitatively measure the carbonaceous components of PM on an hourly averaged basis. The GC-MS OAM is fully automated and has been successfully deployed in the field. It uses a chemically deactivated filter for collection followed by thermal desorption and GC-MS analysis. Laboratory tests show that detection limits range from 0.2 to 3 ng for 16 atmospherically relevant compounds, with the possibility for hundreds more. The GC-MS OAM was deployed in the field for semi-continuous measurement of the organic markers, levoglucosan, dehydroabietic acid, and polycyclic aromatic hydrocarbons (PAHs) from January to March 2015. Results illustrate the significance of this monitoring technique to characterize the organic components of PM and identify sources of pollution.

  9. Role of effluent organic matter in the photochemical degradation of compounds of wastewater origin.

    PubMed

    Bodhipaksha, Laleen C; Sharpless, Charles M; Chin, Yu-Ping; MacKay, Allison A

    2017-03-01

    The photoreactivity of treated wastewater effluent organic matter differs from that of natural organic matter, and the indirect phototransformation rates of micropollutants originating in wastewater are expected to depend on the fractional contribution of wastewater to total stream flow. Photodegradation rates of four common compounds of wastewater origin (sulfamethoxazole, sulfadimethoxine, cimetidine and caffeine) were measured in river water, treated municipal wastewater effluent and mixtures of both to simulate various effluent-stream water mixing conditions that could occur in environmental systems. Compounds were chosen for their unique photodegradation pathways with the photochemically produced reactive intermediates, triplet-state excited organic matter ( 3 OM*), singlet oxygen ( 1 O 2 ), and hydroxyl radicals (OH). For all compounds, higher rates of photodegradation were observed in effluent relative to upstream river water. Sulfamethoxazole degraded primarily via direct photolysis, with some contribution from OH and possibly from carbonate radicals and other unidentified reactive intermediates in effluent-containing samples. Sulfadimethoxine also degraded mainly by direct photolysis, and natural organic matter appeared to inhibit this process to a greater extent than predicted by light screening. In the presence of effluent organic matter, sulfadimethoxine showed additional reactions with OH and 1 O 2 . In all water samples, cimetidine degraded by reaction with 1 O 2 (>95%) and caffeine by reaction with OH (>95%). In river water mixtures, photodegradation rate constants for all compounds increased with increasing fractions of effluent. A conservative mixing model was able to predict reaction rate constants in the case of hydroxyl radical reactions, but it overestimated rate constants in the case of 3 OM* and 1 O 2 pathways. Finally, compound degradation rate constants normalized to the rate of light absorption by water correlated with E 2 /E 3 ratios

  10. Fiber optic micromirror sensor for volatile organic compounds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Butler, M.A.; Ricco, A.J.; Buss, R.

    With the growing concern over environmental pollution, there is a need for sensors to locate and measure the distribution of a wide range of pollutants. In this paper the authors report a fiber optic sensor, based on a thin film micromirror, which responds to a wide range of volatile organic compounds (VOCs). This generic class of sensor will be useful for monitoring applications where the pollutant has already been identified.

  11. Multi-element compound specific stable isotope analysis of volatile organic compounds at trace levels in groundwater samples

    NASA Astrophysics Data System (ADS)

    Herrero-Martín, Sara; Nijenhuis, Ivonne; Schmidt, Marie; Wolfram, Diana; Richnow, Hans. H.; Gehre, Matthias

    2013-04-01

    Groundwater pollution remains one of the major environmental and health concerns. A thorough understanding of sources, sinks and transformation processes of groundwater contaminants is needed to improve risk management evaluation, and to design efficient remediation and water treatment strategies. Isotopic tools provide unique information for an in-depth understanding of the fate of organic chemicals in the environment. During the last decades compound specific isotope analysis (CSIA) of complex mixtures, using gas chromatography-isotope ratio mass spectrometry (GC-IRMS), has gained popularity for the characterization and risk assessment of hazardous waste sites and for isotope forensics of organic contaminants. Multi-element isotope fingerprinting of organic substances provides a more robust framework for interpretation than the isotope analysis of only one element. One major challenge for application of CSIA is the analysis of trace levels of organic compounds in environmental matrices. It is necessary to inject 1 nmol carbon or 8 nmol hydrogen on column, to obtain an accurate and precise measurement of the isotope ratios, which is between two and three orders of magnitude larger than the amount of compound needed for conventional analysis of compound concentrations. Therefore, efficient extraction and pre-concentration techniques have to be integrated with GC-IRMS. Further research is urgently needed in this field, to evaluate the potential of novel and environmental-friendly sample pre-treatment techniques for CSIA to lower the detection limits and extending environmental applications. In this study, the novel coupling of a headspace autosampler (HS) with a programmed temperature vaporizer (PTV), allowing large volume injection of headspace samples, is proposed to improve the sensitivity of CSIA. This automatic, fast and solvent free strategy provides a significant increase on the sensitivity of GC-based methods maintaining the simple headspace instrumentation

  12. SEPARATION OF VOLATILE ORGANIC COMPOUNDS FROM SURFACTANT SOLUTIONS BY PERVAPORATION

    EPA Science Inventory

    Pervaporation is gradually becoming an accepted and practical method for the recovery of volatile organic compounds (VOCs) from aqueous process and waste streams. As the technolog has matured, new applications for pervaporation have emerged. One such application is the separati...

  13. FACTORS IN GEOTROPOSPHERIC PARTICLE-GAS TRANSPORT OF SEMIVOLATILE ORGANIC COMPOUNDS

    EPA Science Inventory

    Semivolatile organic compounds (SVOCs) can exist in solid, liquid, or gas phases under ambient environmental conditions. The geotropospheric transport of SVOCs varies according to the particle type. Two classes of SVOCs and two types of particles were analyzed to determine possib...

  14. SUPERCRITICAL FLUID EXTRACTION OF SEMI-VOLATILE ORGANIC COMPOUNDS FROM PARTICLES

    EPA Science Inventory

    A nitrogen oxide flux chamber was modified to measure the flux of semi-volatile organic compounds (SVOCs). Part of the modification involved the development of methods to extract SVOCs from polyurethane foam (PUF), sand, and soil. Breakthroughs and extraction efficiencies were ...

  15. LEAVES AS INDICATORS OF EXPOSURE TO AIRBORNE VOLATILE ORGANIC COMPOUNDS

    EPA Science Inventory

    The concentration of volatile organic compounds (VOCs) in leaves is primarily a product of airborne exposures and dependent upon bioconcentration factors and release rates. The bioconcentration factors for VOCs in grass are found to be related to their partitioning between octan...

  16. Selective Sorption of Dissolved Organic Carbon Compounds by Temperate Soils

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jagadamma, Sindhu; Mayes, Melanie; Phillips, Jana Randolph

    Physico-chemical sorption of dissolved organic carbon (DOC) on soil minerals is one of the major processes of organic carbon (OC) stabilization in soils, especially in deeper layers. The attachment of C on soil solids is related to the reactivity of the soil minerals and the chemistry of the sorbate functional groups, but the sorption studies conducted without controlling microbial activity may overestimate the sorption potential of soil. This study was conducted to examine the sorptive characteristics of a diverse functional groups of simple OC compounds (D-glucose, L-alanine, oxalic acid, salicylic acid, and sinapyl alcohol) on temperate climate soil orders (Mollisols,more » Ultisols and Alfisols) with and without biological degradative processes. Equilibrium batch experiments were conducted using 0-100 mg C L-1 at a solid-solution ratio of 1:60 for 48 hrs and the sorption parameters were calculated by Langmuir model fitting. The amount of added compounds that remained in the solution phase was detected by high performance liquid chromatography (HPLC) and total organic C (TOC) analysis. Soil sterilization was performed by -irradiation technique and experiments were repeated to determine the contribution of microbial degradation to apparent sorption. Overall, Ultisols did not show a marked preference for apparent sorption of any of the model compounds, as indicated by a narrower range of maximum sorption capacity (Smax) of 173-527 mg kg soil-1 across compounds. Mollisols exhibited a strong preference for apparent sorption of oxalic acid (Smax of 5290 mg kg soil-1) and sinapyl alcohol (Smax of 2031 mg kg soil-1) over the other compounds. The propensity for sorption of oxalic acid is mainly attributed to the precipitation of insoluble Ca-oxalate due to the calcareous nature of most Mollisol subsoils and its preference for sinapyl alcohol could be linked to the polymerization of this lignin monomer on 2:2 mineral dominated soils. The reactivity of Alfisols to DOC

  17. Mobilization and Transport of Organic Compounds from Reservoir Rock and Caprock in Geological Carbon Sequestration Sites

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhong, Lirong; Cantrell, Kirk J.; Mitroshkov, Alexandre V.

    2014-05-06

    Supercritical CO2 (scCO2) is an excellent solvent for organic compounds, including benzene, toluene, ethyl-benzene, and xylene (BTEX), phenols, and polycyclic aromatic hydrocarbons (PAHs). Monitoring results from geological carbon sequestration (GCS) field tests has shown that organic compounds are mobilized following CO2 injection. Such results have raised concerns regarding the potential for groundwater contamination by toxic organic compounds mobilized during GCS. Knowledge of the mobilization mechanism of organic compounds and their transport and fate in the subsurface is essential for assessing risks associated with GCS. Extraction tests using scCO2 and methylene chloride (CH2Cl2) were conducted to study the mobilization of volatilemore » organic compounds (VOCs, including BTEX), the PAH naphthalene, and n-alkanes (n-C20 – n-C30) by scCO2 from representative reservoir rock and caprock obtained from depleted oil reservoirs and coal from an enhanced coal-bed methane recovery site. More VOCs and naphthalene were extractable by scCO2 compared to the CH2Cl2 extractions, while scCO2 extractable alkane concentrations were much lower than concentrations extractable by CH2Cl2. In addition, dry scCO2 was found to extract more VOCs than water saturated scCO2, but water saturated scCO2 mobilized more naphthalene than dry scCO2. In sand column experiments, moisture content was found to have an important influence on the transport of the organic compounds. In dry sand columns the majority of the compounds were retained in the column except benzene and toluene. In wet sand columns the mobility of the BTEX was much higher than that of naphthalene. Based upon results determined for the reservoir rock, caprock, and coal samples studied here, the risk to aquifers from contamination by organic compounds appears to be relatively low; however, further work is necessary to fully evaluate risks from depleted oil reservoirs.« less

  18. REVIEW OF VOLATILE ORGANIC COMPOUND SOURCE APPORTIONMENT BY CHEMICAL MASS BALANCE. (R826237)

    EPA Science Inventory

    The chemical mass balance (CMB) receptor model has apportioned volatile organic compounds (VOCs) in more than 20 urban areas, mostly in the United States. These applications differ in terms of the total fraction apportioned, the calculation method, the chemical compounds used ...

  19. METHOD DEVELOPMENT FOR THE DETERMINATION OF PERFLUORINATED ORGANIC COMPOUNDS ( PFCS ) IN SURFACE WATER

    EPA Science Inventory

    The method for the determination of perfluorinated organic compounds (PFCs) in surface water has been developed and applied to natural water. The method shows an adequate sensitivity, precision and accuracy for ten kinds of target compounds. These PFCs were found in most samples...

  20. Sensory irritating potency of some microbial volatile organic compounds (MVOCs) and a mixture of five MVOCs.

    PubMed

    Korpi, A; Kasanen, J P; Alarie, Y; Kosma, V M; Pasanen, A L

    1999-01-01

    The authors investigated the ability/potencies of 3 microbial volatile organic compounds and a mixture of 5 microbial volatile organic compounds to cause eye and upper respiratory tract irritation (i.e., sensory irritation), with an animal bioassay. The authors estimated potencies by determining the concentration capable of decreasing the respiratory frequency of mice by 50% (i.e., the RD50 value). The RD50 values for 1-octen-3-ol, 3-octanol, and 3-octanone were 182 mg/m3 (35 ppm), 1359 mg/m3 (256 ppm), and 17586 mg/m3 (3360 ppm), respectively. Recommended indoor air levels calculated from the individual RD50 values for 1-octen-3-ol, 3-octanol, and 3-octanone were 100, 1000, and 13000 microg/m3, respectively-values considerably higher than the reported measured indoor air levels for these compounds. The RD50 value for a mixture of 5 microbial volatile organic compounds was also determined and found to be 3.6 times lower than estimated from the fractional concentrations and the respective RD50s of the individual components. The data support the conclusion that a variety of microbial volatile organic compounds may have some synergistic effects for the sensory irritation response, which constrains the interpretation and application of recommended indoor air levels of individual microbial volatile organic compounds. The results also showed that if a particular component of a mixture was much more potent than the other components, it may dominate the sensory irritation effect. With respect to irritation symptoms reported in moldy houses, the results of this study indicate that the contribution of microbial volatile organic compounds to these symptoms seems less than previously supposed.

  1. A comprehensive screen for volatile organic compounds in biological fluids.

    PubMed

    Sharp, M E

    2001-10-01

    A headspace gas chromatographic (GC) screen for common volatile organic compounds in biological fluids is reported. Common GC phases, DB-1 and DB-WAX, with split injection provide separation and identification of more than 40 compounds in a single 20-min run. In addition, this method easily accommodates quantitation. The screen detects commonly encountered volatile compounds at levels below 4 mg%. A control mixture, providing qualitative and semiquantitative information, is described. For comparison, elution of the volatiles on a specialty phase, DB-624, is reported. This method is an expansion and modification of a screen that had been used for more than 20 years. During its first year of use, the expanded screen has proven to be advantageous in routine forensic casework.

  2. World Confederation of Organizations of the Teaching Profession. Annual Report, 1983.

    ERIC Educational Resources Information Center

    World Confederation of Organizations of the Teaching Profession, Morges (Switzerland).

    The constitution and bylaws of the World Confederation of Organizations of the Teaching Profession (WCOTP) are set forth as an introduction to this annual report. The report covers the activities of WCOTP from August 1982 to August 1983. It consists of five parts: (1) action taken to implement resolutions of the Assembly of Delegates; (2)…

  3. Prediction of Partition Coefficients of Organic Compounds between SPME/PDMS and Aqueous Solution

    PubMed Central

    Chao, Keh-Ping; Lu, Yu-Ting; Yang, Hsiu-Wen

    2014-01-01

    Polydimethylsiloxane (PDMS) is commonly used as the coated polymer in the solid phase microextraction (SPME) technique. In this study, the partition coefficients of organic compounds between SPME/PDMS and the aqueous solution were compiled from the literature sources. The correlation analysis for partition coefficients was conducted to interpret the effect of their physicochemical properties and descriptors on the partitioning process. The PDMS-water partition coefficients were significantly correlated to the polarizability of organic compounds (r = 0.977, p < 0.05). An empirical model, consisting of the polarizability, the molecular connectivity index, and an indicator variable, was developed to appropriately predict the partition coefficients of 61 organic compounds for the training set. The predictive ability of the empirical model was demonstrated by using it on a test set of 26 chemicals not included in the training set. The empirical model, applying the straightforward calculated molecular descriptors, for estimating the PDMS-water partition coefficient will contribute to the practical applications of the SPME technique. PMID:24534804

  4. Halogenated Organic Compounds Identified in Hydraulic Fracturing Wastewaters Using Ultrahigh Resolution Mass Spectrometry.

    PubMed

    Luek, Jenna L; Schmitt-Kopplin, Philippe; Mouser, Paula J; Petty, William Tyler; Richardson, Susan D; Gonsior, Michael

    2017-05-16

    Large volumes of water return to the surface following hydraulic fracturing of deep shale formations to retrieve oil and natural gas. Current understanding of the specific organic constituents in these hydraulic fracturing wastewaters is limited to hydrocarbons and a fraction of known chemical additives. In this study, we analyzed hydraulic fracturing wastewater samples using ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) as a nontargeted technique to assign unambiguous molecular formulas to singly charged molecular ions. Halogenated molecular formulas were identified and confirmed using isotopic simulation and MS-MS fragmentation spectra. The abundance of halogenated organic compounds in flowback fluids rather than older wastewaters suggested that the observed molecular ions might have been related to hydraulic fracturing additives and related subsurface reactions, such as through the reaction of shale-extracted chloride, bromide, and iodide with strong oxidant additives (e.g., hypochlorite, persulfate, hydrogen peroxide) and subsequently with diverse dissolved organic matter. Some molecular ions matched the exact masses of known disinfection byproducts including diiodoacetic acid, dibromobenzoic acid, and diiodobenzoic acid. The identified halogenated organic compounds, particularly iodinated organic molecules, are absent from inland natural systems and these compounds could therefore play an important role as environmental tracers.

  5. Diagnosing gastrointestinal illnesses using fecal headspace volatile organic compounds

    PubMed Central

    Chan, Daniel K; Leggett, Cadman L; Wang, Kenneth K

    2016-01-01

    Volatile organic compounds (VOCs) emitted from stool are the components of the smell of stool representing the end products of microbial activity and metabolism that can be used to diagnose disease. Despite the abundance of hydrogen, carbon dioxide, and methane that have already been identified in human flatus, the small portion of trace gases making up the VOCs emitted from stool include organic acids, alcohols, esters, heterocyclic compounds, aldehydes, ketones, and alkanes, among others. These are the gases that vary among individuals in sickness and in health, in dietary changes, and in gut microbial activity. Electronic nose devices are analytical and pattern recognition platforms that can utilize mass spectrometry or electrochemical sensors to detect these VOCs in gas samples. When paired with machine-learning and pattern recognition algorithms, this can identify patterns of VOCs, and thus patterns of smell, that can be used to identify disease states. In this review, we provide a clinical background of VOC identification, electronic nose development, and review gastroenterology applications toward diagnosing disease by the volatile headspace analysis of stool. PMID:26819529

  6. Formation of highly oxygenated organic molecules from aromatic compounds

    NASA Astrophysics Data System (ADS)

    Molteni, Ugo; Bianchi, Federico; Klein, Felix; El Haddad, Imad; Frege, Carla; Rossi, Michel J.; Dommen, Josef; Baltensperger, Urs

    2018-02-01

    Anthropogenic volatile organic compounds (AVOCs) often dominate the urban atmosphere and consist to a large degree of aromatic hydrocarbons (ArHCs), such as benzene, toluene, xylenes, and trimethylbenzenes, e.g., from the handling and combustion of fuels. These compounds are important precursors for the formation of secondary organic aerosol. Here we show that the oxidation of aromatics with OH leads to a subsequent autoxidation chain reaction forming highly oxygenated molecules (HOMs) with an O : C ratio of up to 1.09. This is exemplified for five single-ring ArHCs (benzene, toluene, o-/m-/p-xylene, mesitylene (1,3,5-trimethylbenzene) and ethylbenzene), as well as two conjugated polycyclic ArHCs (naphthalene and biphenyl). We report the elemental composition of the HOMs and show the differences in the oxidation patterns of these ArHCs. A potential pathway for the formation of these HOMs from aromatics is presented and discussed. We hypothesize that AVOCs may contribute substantially to new particle formation events that have been detected in urban areas.

  7. Volatile organic compounds of polyethylene vinyl acetate plastic are toxic to living organisms.

    PubMed

    Meng, Tingzhu Teresa

    2014-01-01

    Volatile organic compounds (VOCs) in polyvinyl chloride (PVC) plastic products readily evaporate; as a result, hazardous gases enter the ecosystem, and cause cancer in humans and other animals. Polyethylene vinyl acetate (PEVA) plastic has recently become a popular alternative to PVC since it is chlorine-free. In order to determine whether PEVA is harmful to humans, this research employed the freshwater oligochaete Lumbriculus variegatus as a model to compare their oxygen intakes while they were exposed to the original stock solutions of PEVA, PVC or distilled water at a different length of time for one day, four days or eight days. During the exposure periods, the oxygen intakes in both PEVA and PVC groups were much higher than in the distilled water group, indicating that VOCs in both PEVA and PVC were toxins that stressed L. variegatus. Furthermore, none of the worms fully recovered during the24-hr recovery period. Additionally, the L. variegatus did not clump together tightly after four or eight days' exposure to either of the two types of plastic solutions, which meant that both PEVA and PVC negatively affected the social behaviors of these blackworms. The LD50 tests also supported the observations above. For the first time, our results have shown that PEVA plastic has adverse effects on living organisms, and therefore it is not a safe alternative to PVC. Further studies should identify specific compounds causing the adverse effects, and determine whether toxic effect occurs in more complex organisms, especially humans.

  8. Biogenic volatile organic compound emissions from vegetation fires

    PubMed Central

    CICCIOLI, PAOLO; CENTRITTO, MAURO; LORETO, FRANCESCO

    2014-01-01

    The aim of this paper was to provide an overview of the current state of the art on research into the emission of biogenic volatile organic compounds (BVOCs) from vegetation fires. Significant amounts of VOCs are emitted from vegetation fires, including several reactive compounds, the majority belonging to the isoprenoid family, which rapidly disappear in the plume to yield pollutants such as secondary organic aerosol and ozone. This makes determination of fire-induced BVOC emission difficult, particularly in areas where the ratio between VOCs and anthropogenic NOx is favourable to the production of ozone, such as Mediterranean areas and highly anthropic temperate (and fire-prone) regions of the Earth. Fire emissions affecting relatively pristine areas, such as the Amazon and the African savannah, are representative of emissions of undisturbed plant communities. We also examined expected BVOC emissions at different stages of fire development and combustion, from drying to flaming, and from heatwaves coming into contact with unburned vegetation at the edge of fires. We conclude that forest fires may dramatically change emission factors and the profile of emitted BVOCs, thereby influencing the chemistry and physics of the atmosphere, the physiology of plants and the evolution of plant communities within the ecosystem. PMID:24689733

  9. Biogenic volatile organic compound emissions from vegetation fires.

    PubMed

    Ciccioli, Paolo; Centritto, Mauro; Loreto, Francesco

    2014-08-01

    The aim of this paper was to provide an overview of the current state of the art on research into the emission of biogenic volatile organic compounds (BVOCs) from vegetation fires. Significant amounts of VOCs are emitted from vegetation fires, including several reactive compounds, the majority belonging to the isoprenoid family, which rapidly disappear in the plume to yield pollutants such as secondary organic aerosol and ozone. This makes determination of fire-induced BVOC emission difficult, particularly in areas where the ratio between VOCs and anthropogenic NOx is favourable to the production of ozone, such as Mediterranean areas and highly anthropic temperate (and fire-prone) regions of the Earth. Fire emissions affecting relatively pristine areas, such as the Amazon and the African savannah, are representative of emissions of undisturbed plant communities. We also examined expected BVOC emissions at different stages of fire development and combustion, from drying to flaming, and from heatwaves coming into contact with unburned vegetation at the edge of fires. We conclude that forest fires may dramatically change emission factors and the profile of emitted BVOCs, thereby influencing the chemistry and physics of the atmosphere, the physiology of plants and the evolution of plant communities within the ecosystem. © 2014 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.

  10. Phenolic compounds and fatty acid composition of organic and conventional grown pecan kernels

    USDA-ARS?s Scientific Manuscript database

    In this study, differences in contents of phenolic compounds and fatty acids in pecan kernels of organically versus conventionally grown pecan cultivars (‘Desirable’, ‘Cheyenne’, and ‘Wichita’) were evaluated. Although we were able to identify nine phenolic compounds (gallic acid, catechol, catechin...

  11. Volatile organic compounds in the unsaturated zone from radioactive wastes

    USGS Publications Warehouse

    Baker, Ronald J.; Andraski, Brian J.; Stonestrom, David A.; Luo, Wentai

    2012-01-01

    Volatile organic compounds (VOCs) are often comingled with low-level radioactive wastes (LLRW), but little is known about subsurface VOC emanations from LLRW landfills. The current study systematically quantified VOCs associated with LLRW over an 11-yr period at the USGS Amargosa Desert Research Site (ADRS) in southwestern Nevada. Unsaturated-zone gas samples of VOCs were collected by adsorption on resin cartridges and analyzed by thermal desorption and GC/MS. Sixty of 87 VOC method analytes were detected in the 110-m-thick unsaturated zone surrounding a LLRW disposal facility. Chlorofluorocarbons (CFCs) were detected in 100% of samples collected. Chlorofluorocarbons are powerful greenhouse gases, deplete stratospheric ozone, and are likely released from LLRW facilities worldwide. Soil-gas samples collected from a depth of 24 m and a horizontal distance 100 m south of the nearest waste-disposal trench contained >60,000 ppbv total VOCs, including >37,000 ppbv CFCs. Extensive sampling in the shallow unsaturated zone (0–2 m deep) identified areas where total VOC concentrations exceeded 5000 ppbv at the 1.5-m depth. Volatile organic compound concentrations exceeded background levels up to 300 m from the facility. Maximum vertical diffusive fluxes of total VOCs were estimated to be 1 g m-2 yr-1. Volatile organic compound distributions were similar but not identical to those previously determined for tritium and elemental mercury. To our knowledge, this study is the first to characterize the unsaturated zone distribution of VOCs emanating from a LLRW landfill. Our results may help explain anomalous transport of radionuclides at the ADRS and elsewhere.

  12. Simulation of Comet Impact and Survivability of Organic Compounds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, B T; Lomov, I N; Blank, J G

    Comets have long been proposed as a potential means for the transport of complex organic compounds to early Earth. For this to be a viable mechanism, a significant fraction of organic compounds must survive the high temperatures due to impact. We have undertaken three-dimensional numerical simulations to track the thermodynamic state of a comet during oblique impacts. The comet was modeled as a 1-km water-ice sphere impacting a basalt plane at 11.2 km/s; impact angles of 15{sup o} (from horizontal), 30{sup o}, 45{sup o}, 65{sup o}, and 90{sup o} (normal impact) were examined. The survival of organic cometary material, modeledmore » as water ice for simplicity, was calculated using three criteria: (1) peak temperatures, (2) the thermodynamic phase of H{sub 2}O, and (3) final temperature upon isentropic unloading. For impact angles greater than or equal to 30{sup o}, no organic material is expected to survive the impact. For the 15{sup o} impact, most of the material survives the initial impact and significant fractions (55%, 25%, and 44%, respectively) satisfy each survival criterion at 1 second. Heating due to deceleration, in addition to shock heating, plays a role in the heating of the cometary material for nonnormal impacts. This effect is more noticeable for more oblique impacts, resulting in significant deviations from estimates using scaling of normal impacts. The deceleration heating of the material at late times requires further modeling of breakup and mixing.« less

  13. Protective effects of novel organic selenium compounds against oxidative stress in the nematode Caenorhabditis elegans.

    PubMed

    Stefanello, Sílvio Terra; Gubert, Priscila; Puntel, Bruna; Mizdal, Caren Rigon; de Campos, Marli Matiko Anraku; Salman, Syed M; Dornelles, Luciano; Avila, Daiana Silva; Aschner, Michael; Soares, Félix Alexandre Antunes

    Organic selenium compounds possess numerous biological properties, including antioxidant activity. Yet, the high toxicity of some of them, such as diphenyl diselenide (DPDS), is a limiting factor in their current usage. Accordingly, we tested four novel organic selenium compounds in the non-parasite nematode Caenorhabditis elegans and compared their efficacy to DPDS. The novel organic selenium compounds are β-selenoamines (1-phenyl-3-( p -tolylselanyl)propan-2-amine (C1) and 1-(2-methoxyphenylselanyl)-3-phenylpropan-2-amine (C2) and analogs of DPDS (1,2-bis (2-methoxyphenyl) diselenide (C3) and 1,2-bis p -tolyldiselenide (C4). Synchronized worms at the L4 larval stage were exposed for one hour in M9 buffer to these compounds. Oxidative stress conditions were induced by juglone (200 μM) and heat shock (35 °C). Moreover, we evaluated Caenorhabditis elegans behavior, GST-4::GFP (glutathione S-transferase) expression and the activity of acetylcholinesterase (AChE). All tested compounds efficiently restored viability in juglone stressed worms. However, DPDS, C2, C3 and C4 significantly decreased the defecation cycle time. Juglone-induced GST-4::GFP expression was not attenuated in worms pretreated with the novel compounds, except with C2. Finally, AChE activity was reduced by DPDS, C2, C3 and C4. To our knowledge, this is study firstly showed the effects of C1, C2, C3 and C4 selenium-derived compounds in Caenorhabditis elegans . Low toxic effects were noted, except for reduction in the defecation cycle, which is likely associated with AChE inhibition. The juglone-induced stress (reduced viability) was fully reversed by compounds to control animal levels. C2 was also efficient in reducing the juglone-induced GST-4::GFP expression, suggesting the latter may mediate the stress induced by this compound. Future studies could be profitably directed at addressing additional molecular mechanisms that mediate the protective effects of these novel organic selenium compounds.

  14. Natural low-molecular mass organic compounds with oxidase activity as organocatalysts.

    PubMed

    Nishiyama, Tatsuya; Hashimoto, Yoshiteru; Kusakabe, Hitoshi; Kumano, Takuto; Kobayashi, Michihiko

    2014-12-02

    Organocatalysts, low-molecular mass organic compounds composed of nonmetallic elements, are often used in organic synthesis, but there have been no reports of organocatalysts of biological origin that function in vivo. Here, we report that actinorhodin (ACT), a natural product derived from Streptomyces coelicolor A3(2), acts as a biocatalyst. We purified ACT and assayed its catalytic activity in the oxidation of L-ascorbic acid and L-cysteine as substrates by analytical methods for enzymes. Our findings were as follows: (i) oxidation reactions producing H2O2 proceeded upon addition of ACT to the reaction mixture; (ii) ACT was not consumed during the reactions; and (iii) a small amount (catalytic amount) of ACT consumed an excess amount of the substrates. Even at room temperature, atmospheric pressure, and neutral pH, ACT showed catalytic activity in aqueous solution, and ACT exhibited substrate specificity in the oxidation reactions. These findings reveal ACT to be an organocatalyst. ACT is known to show antibiotic activity, but its mechanism of action remains unknown. On the basis of our results, we propose that ACT kills bacteria by catalyzing the production of toxic levels of H2O2. We also screened various other natural products of bacterial, plant, and animal origins and found that several of the compounds exhibited catalytic activity, suggesting that living organisms produce and use these compounds as biocatalysts in nature.

  15. Are Some Fungal Volatile Organic Compounds (VOCs) Mycotoxins?

    PubMed Central

    Bennett, Joan W.; Inamdar, Arati A.

    2015-01-01

    Volatile organic compounds (VOCs) are carbon-compounds that easily evaporate at room temperature. Toxins are biologically produced poisons; mycotoxins are those toxins produced by microscopic fungi. All fungi emit blends of VOCs; the qualitative and quantitative composition of these volatile blends varies with the species of fungus and the environmental situation in which the fungus is grown. These fungal VOCs, produced as mixtures of alcohols, aldehydes, acids, ethers, esters, ketones, terpenes, thiols and their derivatives, are responsible for the characteristic moldy odors associated with damp indoor spaces. There is increasing experimental evidence that some of these VOCs have toxic properties. Laboratory tests in mammalian tissue culture and Drosophila melanogaster have shown that many single VOCs, as well as mixtures of VOCs emitted by growing fungi, have toxic effects. This paper describes the pros and cons of categorizing toxigenic fungal VOCs as mycotoxins, uses genomic data to expand on the definition of mycotoxin, and summarizes some of the linguistic and other conventions that can create barriers to communication between the scientists who study VOCs and those who study toxins. We propose that “volatoxin” might be a useful term to describe biogenic volatile compounds with toxigenic properties. PMID:26402705

  16. Chiral Analyses of Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Pizzarello, Sandra

    2004-01-01

    Contents include the following: 1. Characterization of Tagish Lake organic content. The first two grant years were largely devoted to the molecular and isotopic analyses of Tagish Lake organic composition. This carbonaceous meteorite fell in Canada in the winter of the year 2000, and its exceptional atmospheric entry and subsequent recovery (e. g., the sample was recovered and stored by avoiding hand contact and above freezing temperatures) contributed in providing a rare and pristine extraterrestrial material. 2. Chiral analyses of Murchison and Murray soluble organics. One of the most intriguing finding in regard to soluble meteorite organics is the presence within the amino acid suite of some compounds displaying L-enantiomeric excesses. This configuration is exclusive in the amino acids of terrestrial proteins and the finding has raised speculations of a possible role of amino acids from meteorites in the origin of homochirality on the early Earth. The main objective for this NASA funding was the characterization of enantiomeric excesses in meteorites and we have conducted several studies toward establishing their distribution and indignity.

  17. Simulating secondary organic aerosol from missing diesel-related intermediate-volatility organic compound emissions during the Clean Air for London (ClearfLo) campaign

    NASA Astrophysics Data System (ADS)

    Ots, Riinu; Young, Dominique E.; Vieno, Massimo; Xu, Lu; Dunmore, Rachel E.; Allan, James D.; Coe, Hugh; Williams, Leah R.; Herndon, Scott C.; Ng, Nga L.; Hamilton, Jacqueline F.; Bergström, Robert; Di Marco, Chiara; Nemitz, Eiko; Mackenzie, Ian A.; Kuenen, Jeroen J. P.; Green, David C.; Reis, Stefan; Heal, Mathew R.

    2016-05-01

    We present high-resolution (5 km × 5 km) atmospheric chemical transport model (ACTM) simulations of the impact of newly estimated traffic-related emissions on secondary organic aerosol (SOA) formation over the UK for 2012. Our simulations include additional diesel-related intermediate-volatility organic compound (IVOC) emissions derived directly from comprehensive field measurements at an urban background site in London during the 2012 Clean Air for London (ClearfLo) campaign. Our IVOC emissions are added proportionally to VOC emissions, as opposed to proportionally to primary organic aerosol (POA) as has been done by previous ACTM studies seeking to simulate the effects of these missing emissions. Modelled concentrations are evaluated against hourly and daily measurements of organic aerosol (OA) components derived from aerosol mass spectrometer (AMS) measurements also made during the ClearfLo campaign at three sites in the London area. According to the model simulations, diesel-related IVOCs can explain on average ˜ 30 % of the annual SOA in and around London. Furthermore, the 90th percentile of modelled daily SOA concentrations for the whole year is 3.8 µg m-3, constituting a notable addition to total particulate matter. More measurements of these precursors (currently not included in official emissions inventories) is recommended. During the period of concurrent measurements, SOA concentrations at the Detling rural background location east of London were greater than at the central London location. The model shows that this was caused by an intense pollution plume with a strong gradient of imported SOA passing over the rural location. This demonstrates the value of modelling for supporting the interpretation of measurements taken at different sites or for short durations.

  18. Air monitoring of volatile organic compounds at relevant receptors during hydraulic fracturing operations in Washington County, Pennsylvania.

    PubMed

    Maskrey, Joshua R; Insley, Allison L; Hynds, Erin S; Panko, Julie M

    2016-07-01

    A 3-month air monitoring study was conducted in Washington County, Pennsylvania, at the request of local community members regarding the potential risks resulting from air emissions of pollutants related to hydraulic fracturing operations. Continuous air monitoring for total volatile organic compounds was performed at two sampling sites, including a school and a residence, located within 900 m of a hydraulic fracturing well pad that had been drilled prior to the study. Intermittent 24-hour air samples for 62 individual volatile organic compounds were also collected. The ambient air at both sites was monitored during four distinct periods of unconventional natural gas extraction activity: an inactive period prior to fracturing operations, during fracturing operations, during flaring operations, and during another inactive period after operations. The results of the continuous monitoring during fracturing and flaring sampling periods for total volatile organic compounds were similar to the results obtained during inactive periods. Total volatile organic compound 24-hour average concentrations ranged between 0.16 and 80 ppb during all sampling periods. Several individual volatile compounds were detected in the 24-hour samples, but they were consistent with background atmospheric levels measured previously at nearby sampling sites and in other areas in Washington County. Furthermore, a basic yet conservative screening level evaluation demonstrated that the detected volatile organic compounds were well below health-protective levels. The primary finding of this study was that the operation of a hydraulic fracturing well pad in Washington County did not substantially affect local air concentrations of total and individual volatile organic compounds.

  19. Oceanic loading of wildfire-derived organic compounds from a small mountainous river

    USGS Publications Warehouse

    Hunsinger, G.B.; Mitra, Siddhartha; Warrick, J.A.; Alexander, C.R.

    2008-01-01

    Small mountainous rivers (SMRs) export substantial amounts of sediment into the world's oceans. The concomitant yield of organic carbon (OC) associated with this class of rivers has also been shown to be significant and compositionally unique. We report here excessively high loadings of polycyclic aromatic hydrocarbons (PAHs), lignin, and levoglucosan, discharged from the Santa Clara River into the Santa Barbara Channel. The abundance of PAHs, levoglucosan, and lignin in Santa Barbara Channel sediments ranged from 201.7 to 1232.3 ng gdw-1, 1.3 to 6.9 ??g gdw-1, and 0.3 to 2.2 mg per 100 mg of the sedimentary OC, respectively. Assuming a constant rate of sediment accumulation, the annual fluxes of PAHs, levoglucosan, and lignin, to the Santa Barbara Channel were respectively, 885.5 ?? 170.2 ng cm-2 a-1, 3.5 ?? 1.9 ??g cm-2 a-1 and 1.4 ?? 0.3 mg per 100 mg OC cm-2 a-1, over ???30 years. The close agreement between PAHs, levoglucosan, and lignin abundance suggests that the depositional flux of these compounds is largely biomass combustion-derived. To that end, use of the Santa Clara River as a model for SMRs suggests this class of rivers may be one of the largest contributors of pyrolyzed carbon to coastal systems and the open ocean. Wildfire associated carbon discharged from other high yield fluvial systems, when considered collectively, may be a significant source of lignin, pyrolytic PAHs, and other pyrogenic compounds to the ocean. Extrapolating these methods over geologic time may offer useful historical information about carbon sequestration and burial in coastal sediments and affect coastal carbon budgets. Copyright 2008 by the American Geophysical Union.

  20. Composites for removing metals and volatile organic compounds and method thereof

    DOEpatents

    Coronado, Paul R [Livermore, CA; Coleman, Sabre J [Oakland, CA; Reynolds, John G [San Ramon, CA

    2006-12-12

    Functionalized hydrophobic aerogel/solid support structure composites have been developed to remove metals and organic compounds from aqueous and vapor media. The targeted metals and organics are removed by passing the aqueous or vapor phase through the composite which can be in molded, granular, or powder form. The composites adsorb the metals and the organics leaving a purified aqueous or vapor stream. The species-specific adsorption occurs through specific functionalization of the aerogels tailored towards specific metals and/or organics. After adsorption, the composites can be disposed of or the targeted metals and/or organics can be reclaimed or removed and the composites recycled.

  1. Fact Sheets for the Architectural Coating Rule for Volatile Organic Compounds

    EPA Pesticide Factsheets

    This page contains an August 1998 fact sheet with information regarding the National Volatile Organic Compounds Emission Standards for Architectural Coatings Rule. This page also contains information on applicability and compliance for this rule.

  2. Insights into the attenuated sorption of organic compounds on black carbon aged in soil.

    PubMed

    Luo, Lei; Lv, Jitao; Chen, Zien; Huang, Rixiang; Zhang, Shuzhen

    2017-12-01

    Sorption of organic compounds on fresh black carbons (BCs) can be greatly attenuated in soil over time. We examined herein the changes in surface properties of maize straw-derived BCs (biochars) after aged in a black soil and their effects on the sorptive behaviors of naphthalene, phenanthrene and 1,3-dinitrobenzene. Dissolved fulvic and humic acids extracted from the soil were used to explore the role of dissolved organic carbon (DOC) in the aging of biochars. Chromatography analysis indicated that DOC molecules with relatively large molecular weight were preferentially adsorbed on the biochars during the aging processes. DOC sorption led to blockage of the biochar's micropores according to N 2 and CO 2 adsorption analyses. Surface chemistry of the biochars was also substantially modified, with more O-rich functional groups on the aged biochars compared to the original biochars, as evidenced by Near-edge X-ray absorption fine structure (NEXAFS) spectroscopy and X-ray photoelectron spectroscopy (XPS) analyses. The changes in both the physical and chemical surface properties of biochars by DOC led to significant attenuation of the sorption capacity and nonlinearity of the nonionic organic compounds on the aged biochars. Among the tested organic compounds, phenanthrene was the most attenuated in its sorption by the aging treatments, possibly because of its relatively large molecular size and hydrophobicity. The information can help gain a mechanistic understanding of interactions between BCs and organic compounds in soil environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. The effects of ultraviolet light on the degradation of organic compounds - A possible explanation for the absence of organic matter on Mars

    NASA Technical Reports Server (NTRS)

    Oro, J.; Holzer, G.

    1979-01-01

    The analysis of the top layer of the Martian regolith at the two Viking landing sites did not reveal any indigenous organic compounds. However, the existence of such compounds at deeper layers cannot be ruled out. Cosmochemical considerations indicate various potential sources for organic matter on Mars, such as comets and meteorites. The study tested the stability of a sample of the Murchison meteorite and various organic substances which have been detected in carbonaceous chondrites, such as glycine, adenine and naphthalene, to the action of ultraviolet light. The compounds were adsorbed on powdered quartz and on California desert soil and were irradiated in the presence or absence of oxygen. The organic content, before and after irradiation, was measured by carbon elementary analysis, UV-absorption, amino acid analysis or pyrolysis-gas chromatography-mass spectrometry. In the absence of oxygen, adenine and glycine appear to be stable over the given part of irradiation. A definite degradation was noticed in the case of naphtalene and the Murchison meteorite. In the presence of oxygen in amounts comparable to those on Mars all compounds were degraded. The degree of degradation was influenced by the irradiation time, temperature and oxygen content.

  4. Graphene and graphene nanocomposites for the removal of aromatic organic compounds from the water: systematic review

    NASA Astrophysics Data System (ADS)

    Monsores Paixão, Monique; Tadeu Gomes Vianna, Marco; Marques, Marcia

    2018-01-01

    Aromatic organic pollutants are highly toxic to the human and environmental health and are considered as priority pollutants by regulatory agencies. Managing contaminated sites with organic pollutants is one of the major environmental challenges today. Of all technologies that have been proposed to remove contaminants, adsorption is recognized worldwide as an attractive option due to its versatility, wide applicability and economic viability. Recent studies report the use of graphene (GN), a recently carbon nanomaterial, and its derivatives in sorption processes for the removal of aromatic organic compounds. The present review has shown that GN structures are a promising alternative to traditional adsorbent materials, with excellent results in the removal of organic compounds from water, due to their unique structural characteristics and great adsorption capacity for organic compounds. Although, there is still a long way to go until that practical applications can be implemented.

  5. Hammerhead ribozyme activity and oligonucleotide duplex stability in mixed solutions of water and organic compounds

    PubMed Central

    Nakano, Shu-ichi; Kitagawa, Yuichi; Miyoshi, Daisuke; Sugimoto, Naoki

    2014-01-01

    Nucleic acids are useful for biomedical targeting and sensing applications in which the molecular environment is different from that of a dilute aqueous solution. In this study, the influence of various types of mixed solutions of water and water-soluble organic compounds on RNA was investigated by measuring the catalytic activity of the hammerhead ribozyme and the thermodynamic stability of an oligonucleotide duplex. The compounds with a net neutral charge, such as poly(ethylene glycol), small primary alcohols, amide compounds, and aprotic solvent molecules, added at high concentrations changed the ribozyme-catalyzed RNA cleavage rate, with the magnitude of the effect dependent on the NaCl concentration. These compounds also changed the thermodynamic stability of RNA base pairs of an oligonucleotide duplex and its dependence on the NaCl concentration. Specific interactions with RNA molecules and reduced water activity could account for the inhibiting effects on the ribozyme catalysis and destabilizing effects on the duplex stability. The salt concentration dependence data correlated with the dielectric constant, but not with water activity, viscosity, and the size of organic compounds. This observation suggests the significance of the dielectric constant effects on the RNA reactions under molecular crowding conditions created by organic compounds. PMID:25161873

  6. Models for liquid-liquid partition in the system dimethyl sulfoxide-organic solvent and their use for estimating descriptors for organic compounds.

    PubMed

    Karunasekara, Thushara; Poole, Colin F

    2011-07-15

    Partition coefficients for varied compounds were determined for the organic solvent-dimethyl sulfoxide biphasic partition system where the organic solvent is n-heptane or isopentyl ether. These partition coefficient databases are analyzed using the solvation parameter model facilitating a quantitative comparison of the dimethyl sulfoxide-based partition systems with other totally organic partition systems. Dimethyl sulfoxide is a moderately cohesive solvent, reasonably dipolar/polarizable and strongly hydrogen-bond basic. Although generally considered to be non-hydrogen-bond acidic, analysis of the partition coefficient database strongly supports reclassification as a weak hydrogen-bond acid in agreement with recent literature. The system constants for the n-heptane-dimethyl sulfoxide biphasic system provide an explanation of the mechanism for the selective isolation of polycyclic aromatic compounds from mixtures containing low-polarity hydrocarbons based on the capability of the polar interactions (dipolarity/polarizability and hydrogen-bonding) to overcome the opposing cohesive forces in dimethyl sulfoxide that are absent for the interactions with hydrocarbons of low polarity. In addition, dimethyl sulfoxide-organic solvent systems afford a complementary approach to other totally organic biphasic partition systems for descriptor measurements of compounds virtually insoluble in water. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. The biogenic volatile organic compounds emission inventory in France: application to plant ecosystems in the Berre-Marseilles area (France).

    PubMed

    Simon, Valérie; Dumergues, Laurent; Ponche, Jean-Luc; Torres, Liberto

    2006-12-15

    An inventory describing the fluxes of volatile organic compounds (VOCs), isoprene and monoterpenes, and other VOCs (OVOCs) from the biosphere to the atmosphere, has been constructed within the framework of the ESCOMPTE project (fiEld experimentS to COnstrain Models of atmospheric Pollution and Transport of Emissions). The area concerned, located around Berre-Marseilles, is a Mediterranean region frequently subject to high ozone concentrations. The inventory has been developed using a fine scale land use database for the year 1999, forest composition statistics, emission potentials from individual plant species, biomass distribution, temperature and light intensity. The seasonal variations in emission potentials and biomass were also taken into account. Hourly meteorological data for 1999 were calculated from ALADIN data and these were used to predict the hourly isoprene, monoterpene and OVOC fluxes for the area on a 1 kmx1 km spatial grid. Estimates of annual biogenic isoprene, monoterpene and OVOC fluxes for the reference year 1999 were 20.6, 38.9 and 13.3 kt, respectively, Quercus pubescens, Quercus ilex, Pinus halepensis and garrigue vegetation are the dominant emitting species of the area. VOC emissions from vegetation in this region contribute approximately 94% to the NMVOC (non-methane volatile organic compounds) of natural origin and are of the same order of magnitude as NMVOC emissions from anthropogenic sources. These results complete the global ESCOMPTE database needed to make an efficient strategy for tropospheric ozone reduction policy.

  8. Potential of select intermediate-volatility organic compounds and consumer products for secondary organic aerosol and ozone formation under relevant urban conditions

    NASA Astrophysics Data System (ADS)

    Li, Weihua; Li, Lijie; Chen, Chia-li; Kacarab, Mary; Peng, Weihan; Price, Derek; Xu, Jin; Cocker, David R.

    2018-04-01

    Emissions of certain low vapor pressure-volatile organic compounds (LVP-VOCs) are considered exempt to volatile organic compounds (VOC) regulations due to their low evaporation rates. However, these compounds may still play a role in ambient secondary organic aerosol (SOA) and ozone formation. The LVP-VOCs selected for this work are categorized as intermediate-volatility organic compounds (IVOCs) according to their vapor pressures and molecular formulas. In this study, the evaporation rates of 14 select IVOCs are investigated with half of them losing more than 95% of their mass in less than one month. Further, SOA and ozone formation are presented from 11 select IVOCs and 5 IVOC-containing generic consumer products under atmospherically relevant conditions using varying radical sources (NOx and/or H2O2) and a surrogate reactive organic gas (ROG) mixture. Benzyl alcohol (0.41), n-heptadecane (0.38), and diethylene glycol monobutyl ether (0.16) are determined to have SOA yields greater than 0.1 in the presence of NOx and a surrogate urban hydrocarbon mixture. IVOCs also influence ozone formation from the surrogate urban mixture by impacting radical levels and NOx availability. The addition of lab created generic consumer products has a weak influence on ozone formation from the surrogate mixture but strongly affects SOA formation. The overall SOA and ozone formation of the generic consumer products could not be explained solely by the results of the pure IVOC experiments.

  9. Refractory Organic Compounds in Enceladus' Ice Grains and Hydrothermal Activity

    NASA Astrophysics Data System (ADS)

    Postberg, F.; Khawaja, N.; Hsu, H. W.; Sekine, Y.; Shibuya, T.

    2015-12-01

    Cassini's Cosmic Dust Analyzer (CDA) generates time-of-flight mass spectra of individual grains impinging on the instruments target-plate. Following the analysis of salt rich ice grains emitted by Enceladus that indicated a salt-water ocean in contact with the moon's rocky core [1,2] a recent CDA analysis of nano-phase silica particles pointed at hydrothermal activity at the moon's rock/water interface [3]. The results imply temperatures above 80 - 90°C and alkaline pH values around 10 reminiscent of alkaline hydrothermal vents on Earth like the Lost City Hydrothermal Field. In this context the compositional analysis of organic components in CDA mass spectra of the ejected ice grains is of particular relevance. A multitude of volatile organic species has already been identified in the gas component of the plume [4]. As expected, we find more complex organic molecules in ice grains than in the gas indicating aromatic species, amines, and carbonyl group species. The composition of organic-bearing ice grains displays a great diversity indicating a variety of different organic species in varying concentrations. Recent spatially resolved CDA in situ measurements inside Enceladus' plume indicate that these organic compounds are especially frequent in 'young' ice grains that have just been ejected by high velocity jets. We investigate the implications of our findings with respect to ice grain formation at the water surface and inside the icy vents. We constrain the generation of organic compounds at the rock/water interface in the light of hydrothermal activity and the potential for the formation of life precursor molecules in Enceladus' ocean. Ref:[1] Postberg et al., Nature 459, 1098-1101 (2009). [2] Postberg et al., Nature 474, 620-622 (2011). [3]. Hsu, Postberg, Sekine et al., Nature, 519, 207-210 (2015). [4] Waite et al., Nature 460, 487-490 (2009).

  10. Analyses of volatile organic compounds from human skin

    PubMed Central

    Gallagher, M.; Wysocki, C.J.; Leyden, J.J.; Spielman, A.I.; Sun, X.; Preti, G.

    2008-01-01

    Summary Background Human skin emits a variety of volatile metabolites, many of them odorous. Much previous work has focused upon chemical structure and biogenesis of metabolites produced in the axillae (underarms), which are a primary source of human body odour. Nonaxillary skin also harbours volatile metabolites, possibly with different biological origins than axillary odorants. Objectives To take inventory of the volatile organic compounds (VOCs) from the upper back and forearm skin, and assess their relative quantitative variation across 25 healthy subjects. Methods Two complementary sampling techniques were used to obtain comprehensive VOC profiles, viz., solid-phase micro extraction and solvent extraction. Analyses were performed using both gas chromatography/mass spectrometry and gas chromatography with flame photometric detection. Results Nearly 100 compounds were identified, some of which varied with age. The VOC profiles of the upper back and forearm within a subject were, for the most part, similar, although there were notable differences. Conclusions The natural variation in nonaxillary skin odorants described in this study provides a baseline of compounds we have identified from both endogenous and exogenous sources. Although complex, the profiles of volatile constituents suggest that the two body locations share a considerable number of compounds, but both quantitative and qualitative differences are present. In addition, quantitative changes due to ageing are also present. These data may provide future investigators of skin VOCs with a baseline against which any abnormalities can be viewed in searching for biomarkers of skin diseases. PMID:18637798

  11. Bonded-phase extraction column isolation of organic compounds in groundwater at a hazardous waste site

    USGS Publications Warehouse

    Rostad, C.E.; Pereira, W.E.; Ratcliff, S.M.

    1984-01-01

    A procedure for isolation of hazardous organic compounds from water for gas chromatography/mass spectrometry analysis Is presented and applied to creosote- and pentachlorophenol-contaminated groundwater resulting from wood-treatment processes. This simple procedure involved passing a 50-100-mL sample through a bonded-phase extraction column, eluting the trapped organic compounds from the column with 2-4 mL of solvent, and evaporating the sample to 100 ??L with a stream of dry nitrogen, after which the sample was ready for gas chromatography/mass spectrometry analysis. Representative compounds indicative of creosote contamination were used for recovery and precision studies from the cyclohexyl-bonded phase. Recovery of these compounds from n-octyl-, n-octadecyl-, cyclohexyl-, and phenyl-bonded phases was compared. The bonded phase that exhibited the best recovery and least bias toward acidic or basic cmpounds was the n-octadecyl phase. Detailed compound Identification Is given for compounds Isolated from creosote- and pentachlorophenol-contaminated groundwater using the cyclohexyl-bonded phase.

  12. ESTIMATION OF PHYSICAL PROPERTIES AND CHEMICAL REACTIVITY PARAMETERS OF ORGANIC COMPOUNDS

    EPA Science Inventory

    The computer program SPARC (Sparc Performs Automated Reasoning in Chemistry)has been under development for several years to estimate physical properties and chemical reactivity parameters of organic compounds strictly from molecular structure. SPARC uses computational algorithms ...

  13. IRRADIATION METHOD OF CONVERTING ORGANIC COMPOUNDS

    DOEpatents

    Allen, A.O.; Caffrey, J.M. Jr.

    1960-10-11

    A method is given for changing the distribution of organic compounds from that produced by the irradiation of bulk alkane hydrocarbons. This method consists of depositing an alkane hydrocarbon on the surface of a substrate material and irradiating with gamma radiation at a dose rate of more than 100,000 rads. The substrate material may be a metal, metal salts, metal oxides, or carbons having a surface area in excess of 1 m/sup 2//g. The hydrocarbons are deposited in layers of from 0.1 to 10 monolayers on the surfaces of these substrates and irradiated. The product yields are found to vary from those which result from the irradiation of bulk hydrocarbons in that there is an increase in the quantity of branched hydrocarbons.

  14. MECHANISTIC ROLES OF SOIL HUMUS AND MINERALS IN THE SORPTION OF NONIONIC ORGANIC COMPOUNDS FROM AQUEOUS AND ORGANIC SOLUTIONS

    EPA Science Inventory

    Mechanistic roles of soil humus and soil minerals and their contributions to soil sorption of nonionic organic compounds from aqueous and organic solutions are illustrated. Parathion and lindane are used as model solutes on two soils that differ greatly in their humic and mineral...

  15. Novel collection method for volatile organic compounds (VOCs) from dogs

    USDA-ARS?s Scientific Manuscript database

    Host derived chemical cues are an important aspect of arthropod attraction to potential hosts. Host cues that act over longer distances include CO2, heat, and water vapor, while cues such as volatile organic compounds (VOCs) act over closer distances. Domestic dogs are important hosts for disease cy...

  16. Trace element, semivolatile organic, and chlorinated organic compound concentrations in bed sediments of selected streams at Fort Gordon, Georgia, February-April 2010

    USGS Publications Warehouse

    Thomas, Lashun K.; Journey, Celeste A.; Stringfield, Whitney J.; Clark, Jimmy M.; Bradley, Paul M.; Wellborn, John B.; Ratliff, Hagan; Abrahamsen, Thomas A.

    2011-01-01

    A spatial survey of streams was conducted from February to April 2010 to assess the concentrations of major ions, selected trace elements, semivolatile organic compounds, organochlorine pesticides, and polychlorinated biphenyls associated with the bed sediments of surface waters at Fort Gordon military installation near Augusta, Georgia. This investigation expanded a previous study conducted in May 1998 by the U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, that evaluated the streambed sediment quality of selected surface waters at Fort Gordon. The data presented in this report are intended to help evaluate bed sediment quality in relation to guidelines for the protection of aquatic life, and identify temporal trends in trace elements and semivolatile organic compound concentrations at streambed sites previously sampled. Concentrations of 34 major ions and trace elements and 102 semivolatile organic, organochlorine pesticide, and polychlorinated biphenyl compounds were determined in the fine-grained fraction of bed sediment samples collected from 13 of the original 29 sites in the previous study, and 22 additional sites at Fort Gordon. Three of the sites were considered reference sites as they were presumed to be located away from potential sources of contaminants and were selected to represent surface waters flowing onto the fort, and the remaining 32 nonreference sites were presumed to be located within the contamination area at the fort. Temporal trends in trace elements and semivolatile organic compound concentrations also were evaluated at 13 of the 32 nonreference sites to provide an assessment of the variability in the number of detections and concentrations of constituents in bed sediment associated with potential sources, accumulation, and attenuation processes. Major ion and trace element concentrations in fine-grained bed

  17. Using portable Raman spectrometers for the identification of organic compounds at low temperatures and high altitudes: exobiological applications.

    PubMed

    Jehlicka, J; Edwards, H G M; Culka, A

    2010-07-13

    Organic minerals, organic acids and NH-containing organic molecules represent important target molecules for astrobiology. Here, we present the results of the evaluation of a portable hand-held Raman spectrometer to detect these organic compounds outdoors under field conditions. These measurements were carried out during the February-March 2009 winter period in Austrian Alpine sites at temperatures ranging between -5 and -25 degrees C. The compounds investigated were detected under field conditions and their main Raman spectral features were observed unambiguously at their correct reference wavenumber positions. The results obtained demonstrate that a miniaturized Raman spectrometer equipped with 785 nm excitation could be applied with advantage as a key instrument for investigating the presence of organic minerals, organic acids and nitrogen-containing organic compounds outdoors under terrestrial low-temperature conditions. Within the payload designed by ESA and NASA for several missions focusing on Mars, Titan, Europa and other extraterrestrial bodies, Raman spectroscopy can be proposed as an important non-destructive analytical tool for the in situ identification of organic compounds relevant to life detection on planetary and moon surfaces or near subsurfaces.

  18. Evaluation of employee exposure to organic tin compounds used as stabilizers at PVC processing facilities.

    PubMed

    Boraiko, Carol; Batt, John

    2005-02-01

    Organic tin compounds are primary substances used as heat stabilizers by the polyvinyl chloride (PVC) industry. The use of these compounds in the PVC industry is generally well controlled, usually by automated processes. This study was conducted to provide an overview of worker exposure to organic tin compounds at PVC processing facilities and to verify that these exposures are below the threshold limit value (TLV((R))) set by the American Conference of Governmental Industrial Hygienists for organic tin. The basis of the TLV indicates the principal concern is to minimize adverse effects on immune function and the central nervous system from airborne exposure to organic tin. The TLV has a skin designation based on the potential for percutaneous absorption; the TLVs for inhalation exposures are based on the presumption that there is no concurrent exposure via the skin and oral ingestion routes. Personal exposure monitoring was conducted following the National Institute for Occupational Safety and Health (NIOSH) 5504 sampling method and a modified version of the NIOSH analytical method. The results were reported as"total tin."The data indicated no average exposure levels for individual tasks exceeded the organic tin TLV, and 96%of results the samples were less than 20%of the TLV. Only 1 sample of 102 exceeded the TLV, and the individual was wearing appropriate respiratory protection. Subsequent investigation indicated the highest exposures occurred while the operators were conducting tasks that included manual handling of the organic tin compounds. These data suggest manual operations may have a greater potential for organic tin exposure.

  19. Extraction of organic compounds with room temperature ionic liquids.

    PubMed

    Poole, Colin F; Poole, Salwa K

    2010-04-16

    Room temperature ionic liquids are novel solvents with a rather specific blend of physical and solution properties that makes them of interest for applications in separation science. They are good solvents for a wide range of compounds in which they behave as polar solvents. Their physical properties of note that distinguish them from conventional organic solvents are a negligible vapor pressure, high thermal stability, and relatively high viscosity. They can form biphasic systems with water or low polarity organic solvents and gases suitable for use in liquid-liquid and gas-liquid partition systems. An analysis of partition coefficients for varied compounds in these systems allows characterization of solvent selectivity using the solvation parameter model, which together with spectroscopic studies of solvent effects on probe substances, results in a detailed picture of solvent behavior. These studies indicate that the solution properties of ionic liquids are similar to those of polar organic solvents. Practical applications of ionic liquids in sample preparation include extractive distillation, aqueous biphasic systems, liquid-liquid extraction, liquid-phase microextraction, supported liquid membrane extraction, matrix solvents for headspace analysis, and micellar extraction. The specific advantages and limitations of ionic liquids in these studies is discussed with a view to defining future uses and the need not to neglect the identification of new room temperature ionic liquids with physical and solution properties tailored to the needs of specific sample preparation techniques. The defining feature of the special nature of ionic liquids is not their solution or physical properties viewed separately but their unique combinations when taken together compared with traditional organic solvents. Copyright 2009 Elsevier B.V. All rights reserved.

  20. Nitrate radicals and biogenic volatile organic compounds ...

    EPA Pesticide Factsheets

    Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO3) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 decades, during which time a large body of research has emerged from laboratory, field, and modeling studies. NO3-BVOC reactions influence air quality, climate and visibility through regional and global budgets for reactive nitrogen (particularly organic nitrates), ozone, and organic aerosol. Despite its long history of research and the significance of this topic in atmospheric chemistry, a number of important uncertainties remain. These include an incomplete understanding of the rates, mechanisms, and organic aerosol yields for NO3-BVOC reactions, lack of constraints on the role of heterogeneous oxidative processes associated with the NO3 radical, the difficulty of characterizing the spatial distributions of BVOC and NO3 within the poorly mixed nocturnal atmosphere, and the challenge of constructing appropriate boundary layer schemes and non-photochemical mechanisms for use in state-of-the-art chemical transport and chemistry–climate models. This review is the result of a workshop of the same title held at the Georgia Institute of Technology in June 2015. The first half of the review summarizes the current literature on NO3-BVOC chemistry, with a particular focus on recent advances in

  1. Responses of polar organic compounds to different ionic environments in aqueous media are interrelated.

    PubMed

    Ferreira, L A; Chervenak, A; Placko, S; Kestranek, A; Madeira, P P; Zaslavsky, B Y

    2014-11-14

    Solubilities of 17 polar organic compounds in aqueous solutions of Na2SO4, NaCl, NaClO4, and NaSCN at the salt concentrations of up to 1.0-2.0 M were determined and the Setschenow constant, ksalt, values were estimated. It was found that NaClO4 may display both salting-in and salting-out effects depending on the particular compound structure. The Setschenow constant values for all the polar compounds examined in different salt solutions are found to be interrelated. Similar relationships were observed for partition coefficients of nonionic organic compounds in aqueous polyethylene glycol-sodium sulfate two-phase systems in the presence of different salt additives reported previously [Ferreira et al., J. Chromatogr. A, 2011, 1218, 5031], and for the effects of different salts on optical rotation of amino acids reported by Rossi et al. [J. Phys. Chem. B, 2007, 111, 10510]. In order to explain the observed relationships it is suggested that all the effects observed originate as responses of the compounds to the presence of a given ionic environment and its interaction with the compounds by forming direct or solvent-separated ionic pairs. The response is compound-specific and its strength is determined by the compound structure and the type (and concentration) of ions inducing the response.

  2. Synthetic organic compounds and their transformation products in groundwater: occurrence, fate and mitigation.

    PubMed

    Postigo, Cristina; Barceló, Damià

    2015-01-15

    Groundwater constitutes the main source of public drinking water supply in many regions. Thus, the contamination of groundwater resources by organic chemicals is a matter of growing concern because of its potential effects on public health. The present manuscript compiles the most recent works related to the study of synthetic organic compounds (SOCs) in groundwater, with special focus on the occurrence of contaminants not or barely covered by previously published reviews, e.g., pesticide and pharmaceutical transformation products, lifestyle products, and industrial chemicals such as corrosion inhibitors, brominated and organophosphate flame retardants, plasticizers, volatile organic compounds (VOCs), and polycyclic aromatic hydrocarbons (PAHs). Moreover, the main challenges in managed aquifer recharge, i.e., reclaimed water injection and infiltration, and riverbank filtration, regarding natural attenuation of organic micropollutants are discussed, and insights into the future chemical quality of groundwater are provided. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Mixed organic compound-ionic liquid electrolytes for lithium battery electrolyte systems

    NASA Astrophysics Data System (ADS)

    Montanino, M.; Moreno, M.; Carewska, M.; Maresca, G.; Simonetti, E.; Lo Presti, R.; Alessandrini, F.; Appetecchi, G. B.

    2014-12-01

    The thermal, transport, rheological and flammability properties of electrolyte mixtures, proposed for safer lithium-ion battery systems, were investigated as a function of the mole composition. The blends were composed of a lithium salt (LiTFSI), organic solvents (namely EC, DEC) and an ionic liquid (PYR13TFSI). The main goal is to combine the fast ion transport properties of the organic compounds with the safe issues of the non-flammable and non-volatile ionic liquids. Preliminary tests in batteries have evidenced cycling performance approaching that observed in commercial organic electrolytes.

  4. Composition of semi-volatile organic compounds in the urban atmosphere of Singapore: influence of biomass burning

    NASA Astrophysics Data System (ADS)

    He, J.; Zielinska, B.; Balasubramanian, R.

    2010-04-01

    An intensive field study was conducted in the urban atmosphere of Singapore to investigate the composition of organic compounds in both gaseous and particulate phases during the period of August to early November 2006. 17 atmospheric samples were collected. These samples were subjected to accelerated solvent extraction with a mixture of dichloromethane and acetone and separated into functional group fractions for analyses by GC/MS. Over 180 organic compounds belonging to three major fractions (n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and polar organic compounds (POCs)) were identified and quantified. The characteristics and abundance of the n-alkanes, PAHs, mono and dicarboxylic acids, methoxylated phenols and other POCs were determined. The composition of these organic compounds fluctuated temporally with most of them being relatively higher in October than those in other months of the sampling period. 3-D backward air mass trajectory analyses together with the carbon preference index (CPI), molecular diagnostic ratios and molecular markers were used to investigate the origin of organic species measured in this study. Based on these diagnostic tools, the increased abundance of atmospheric organic species during October could be attributed to the occurrence of regional smoke haze episodes due to biomass burning in Indonesia. Among the POCs investigated, phthalic acid and cis-pinonic acid showed a strong linear relationship with maximum daily ozone concentration, indicating secondary organic aerosols (SOA) to be an important contributor to ambient atmospheric organics over Singapore.

  5. Microbial use of gas phase organic compounds in the surface ocean

    NASA Astrophysics Data System (ADS)

    Arrieta, Jesus M.; Duarte, Carlos M.; Monserrat Sala, M.; Dachs, Jordi

    2016-04-01

    Large diffusive air-sea fluxes of gas-phase organic carbon (GOC) have been identified, indicating that the ocean may be a major sink for these compounds. However, little is known about the fate of these GOC compounds entering the surface ocean. We report efficient use of atmospheric GOC by marine prokaryotes at different locations in the NE Subtropical Atlantic Ocean, the Arctic Ocean and the Mediterranean Sea. Our results indicate that between 2 to 27% of the prokaryotic carbon demand was supported by GOC. Between 1 and 94% of the GOC entering the ocean was consumed by prokaryotes depending on locations, thus sustaining a disequilibrium, which drives the transfer of GOC from the atmosphere into the ocean. The magnitude of this, previously unnoticed, microbial GOC utilization stresses the need for incorporating the oceanic uptake of gaseous organic carbon into the global carbon budget.

  6. 78 FR 44574 - Third Annual Food and Drug Administration Health Professional Organizations Conference

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-24

    ... . Contact: Brenda Rose, Office of Special Health Issues, 10903 New Hampshire Ave., Silver Spring, MD 20993... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2013-N-0001] Third Annual Food and Drug Administration Health Professional Organizations Conference AGENCY: Food and...

  7. Energetic Limitations on Microbial Respiration of Organic Compounds using Aqueous Fe(III) Complexes

    NASA Astrophysics Data System (ADS)

    Naughton, H.; Fendorf, S. E.

    2015-12-01

    Soil organic matter constitutes up to 75% of the terrestrial carbon stock. Microorganisms mediate the breakdown of organic compounds and the return of carbon to the atmosphere, predominantly through respiration. Microbial respiration requires an electron acceptor and an electron donor such as small fatty acids, organic acids, alcohols, sugars, and other molecules that differ in oxidation state of carbon. Carbon redox state affects how much energy is required to oxidize a molecule through respiration. Therefore, different organic compounds should offer a spectrum of energies to respiring microorganisms. However, microbial respiration has traditionally focused on the availability and reduction potential of electron acceptors, ignoring the organic electron donor. We found through incubation experiments that the organic compound serving as electron donor determined how rapidly Shewanella putrefaciens CN32 respires organic substrate and the extent of reduction of the electron acceptor. We simulated a range of energetically favorable to unfavorable electron acceptors using organic chelators bound to Fe(III) with equilibrium stability constants ranging from log(K) of 11.5 to 25.0 for the 1:1 complex, where more stable complexes are less favorable for microbial respiration. Organic substrates varied in nominal oxidation state of carbon from +2 to -2. The most energetically favorable substrate, lactate, promoted up to 30x more rapid increase in percent Fe(II) compared to less favorable substrates such as formate. This increased respiration on lactate was more substantial with less stable Fe(III)-chelate complexes. Intriguingly, this pattern contradicts respiration rate predicted by nominal oxidation state of carbon. Our results suggest that organic substrates will be consumed so long as the energetic toll corresponding to the electron donor half reaction is counterbalanced by the energy available from the electron accepting half reaction. We propose using the chemical

  8. Semi-empirical estimation of organic compound fugacity ratios at environmentally relevant system temperatures.

    PubMed

    van Noort, Paul C M

    2009-06-01

    Fugacity ratios of organic compounds are used to calculate (subcooled) liquid properties, such as solubility or vapour pressure, from solid properties and vice versa. They can be calculated from the entropy of fusion, the melting temperature, and heat capacity data for the solid and the liquid. For many organic compounds, values for the fusion entropy are lacking. Heat capacity data are even scarcer. In the present study, semi-empirical compound class specific equations were derived to estimate fugacity ratios from molecular weight and melting temperature for polycyclic aromatic hydrocarbons and polychlorinated benzenes, biphenyls, dibenzo[p]dioxins and dibenzofurans. These equations estimate fugacity ratios with an average standard error of about 0.05 log units. In addition, for compounds with known fusion entropy values, a general semi-empirical correction equation based on molecular weight and melting temperature was derived for estimation of the contribution of heat capacity differences to the fugacity ratio. This equation estimates the heat capacity contribution correction factor with an average standard error of 0.02 log units for polycyclic aromatic hydrocarbons, polychlorinated benzenes, biphenyls, dibenzo[p]dioxins and dibenzofurans.

  9. Antioxidant activity and phenolic compounds in organic red wine using different winemaking techniques.

    PubMed

    Mulero, Juana; Zafrilla, Pilar; Cayuela, Jose M; Martínez-Cachá, Adela; Pardo, Francisco

    2011-04-01

    Wine phenolic composition depends on the grapes used to make wine and on vinification conditions. The occurrence of these biological compounds has stimulated numerous studies focused on understanding the mechanisms that influence their concentrations in wine. This article studied the effect of different vinification techniques on the antioxidant activity and on the phenolic compounds of red wine made from the variety of Monastrell grapes obtained by organic culture. To this purpose, 3 different vinification procedures were carried out: vinification after prolonged maceration, vinification with the addition of enological enzymes, and traditional vinification procedures (used as control).The results showed similar values of antioxidant activity in all 3 types of wine elaborated and found no differences in the concentrations of the different types of phenolic compounds in wine made with the 3 different methods. The evolution of antioxidant activity and phenolic compounds tested in wines during 3 mo of storage showed a similar pattern. Organic wine has acquired an important role in the economic world and its important, working in oenology to research in this field.

  10. Development and Mining of a Volatile Organic Compound Database

    PubMed Central

    Abdullah, Azian Azamimi; Ono, Naoaki; Sugiura, Tadao; Morita, Aki Hirai; Katsuragi, Tetsuo; Muto, Ai; Nishioka, Takaaki; Kanaya, Shigehiko

    2015-01-01

    Volatile organic compounds (VOCs) are small molecules that exhibit high vapor pressure under ambient conditions and have low boiling points. Although VOCs contribute only a small proportion of the total metabolites produced by living organisms, they play an important role in chemical ecology specifically in the biological interactions between organisms and ecosystems. VOCs are also important in the health care field as they are presently used as a biomarker to detect various human diseases. Information on VOCs is scattered in the literature until now; however, there is still no available database describing VOCs and their biological activities. To attain this purpose, we have developed KNApSAcK Metabolite Ecology Database, which contains the information on the relationships between VOCs and their emitting organisms. The KNApSAcK Metabolite Ecology is also linked with the KNApSAcK Core and KNApSAcK Metabolite Activity Database to provide further information on the metabolites and their biological activities. The VOC database can be accessed online. PMID:26495281

  11. Prediction of cloud condensation nuclei activity for organic compounds using functional group contribution methods

    DOE PAGES

    Petters, M. D.; Kreidenweis, S. M.; Ziemann, P. J.

    2016-01-19

    A wealth of recent laboratory and field experiments demonstrate that organic aerosol composition evolves with time in the atmosphere, leading to changes in the influence of the organic fraction to cloud condensation nuclei (CCN) spectra. There is a need for tools that can realistically represent the evolution of CCN activity to better predict indirect effects of organic aerosol on clouds and climate. This work describes a model to predict the CCN activity of organic compounds from functional group composition. Following previous methods in the literature, we test the ability of semi-empirical group contribution methods in Kohler theory to predict themore » effective hygroscopicity parameter, kappa. However, in our approach we also account for liquid–liquid phase boundaries to simulate phase-limited activation behavior. Model evaluation against a selected database of published laboratory measurements demonstrates that kappa can be predicted within a factor of 2. Simulation of homologous series is used to identify the relative effectiveness of different functional groups in increasing the CCN activity of weakly functionalized organic compounds. Hydroxyl, carboxyl, aldehyde, hydroperoxide, carbonyl, and ether moieties promote CCN activity while methylene and nitrate moieties inhibit CCN activity. Furthermore, the model can be incorporated into scale-bridging test beds such as the Generator of Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) to evaluate the evolution of kappa for a complex mix of organic compounds and to develop suitable parameterizations of CCN evolution for larger-scale models.« less

  12. Bioremediation of trace organic compounds found in precious metals refineries' wastewaters: a review of potential options.

    PubMed

    Barbosa, V L; Tandlich, R; Burgess, J E

    2007-07-01

    Platinum group metal (PGM) refining processes produce large quantities of wastewater, which is contaminated with the compounds that make up the solvents/extractants mixtures used in the process. These compounds often include solvesso, beta-hydroxyxime, amines, amides and methyl isobutyl ketone. A process to clean up PGM refinery wastewaters so that they could be re-used in the refining process would greatly contribute to continual water storage problems and to cost reduction for the industry. Based on the concept that organic compounds that are produced biologically can be destroyed biologically, the use of biological processes for the treatment of organic compounds in other types of waste stream has been favoured in recent years, owing to their low cost and environmental acceptability. This review examines the available biotechnologies and their effectiveness for treating compounds likely to be contained in precious metal extraction process wastewaters. The processes examined include: biofilters, fluidized bed reactors, trickle-bed bioreactors, bioscrubbers, two-phase partitioning bioreactors, membrane bioreactors and activated sludge. Although all processes examined showed adequate to excellent removal of organic compounds from various gaseous and fewer liquid waste streams, there was a variation in their effectiveness. Variations in performance of laboratory-scale biological processes are probably due to the inherent change in the microbial population composition due to selection pressure, environmental conditions and the time allowed for adaptation to the organic compounds. However, if these factors are disregarded, it can be established that activated sludge and membrane bioreactors are the most promising processes for use in the treatment of PGM refinery wastewaters.

  13. Characterisation of antioxidant compounds in sweet bell pepper (Capsicum annuum L.) under organic and conventional growing systems.

    PubMed

    Hallmann, Ewelina; Rembiałkowska, Ewa

    2012-09-01

    Sweet red bell pepper is one of the best sources of ascorbic acid and carotenoids as well as phenolic compounds important in the human diet. There have been some studies showing a higher level of bioactive compounds in organic bell pepper fruits compared with conventional fruits, but not all studies have been consistent in this respect. The levels of carotenoids and phenolics are very variable and may be affected by ripeness, genotype and cultivation. The results obtained in this study showed that an organic growing system affected the level of bioactive compounds (carotenoids and polyphenols) in sweet bell pepper fruits cultivated in Poland. Organic bell pepper fruits contained significantly more dry matter, vitamin C, total carotenoids, β-carotene, α-carotene, cis-β-carotene, total phenolic acids (as well as individual gallic and chlorogenic acids) and flavonoids (quercetin D-glucoside, quercetin and kaempferol) compared with conventional fruits. The bell pepper variety also affected the level of antioxidant compounds in fruits. Organic growing increased the level of antioxidant compounds such as carotenoids, phenolic compounds and vitamin C in sweet bell pepper. The second significant factor affecting the antioxidant compound content of sweet bell pepper was variety. It would be necessary to continue this study as a long-term experiment in order to eliminate the influence of seasonality. Copyright © 2012 Society of Chemical Industry.

  14. VOLATILE ORGANIC COMPOUNDS AS BREATH BIOMARKERS FOR ACTIVE AND PASSIVE SMOKING

    EPA Science Inventory

    Real-time breath measurement technology was used to investigate the suitability of some volatile organic compounds (VOCs) to serve as breath biomarkers for active and passive smoking and to measure actual exposures and resulting breath concentrations for persons exposed to toba...

  15. Volatile Organic Sulfur Compounds of Environmental Interest: Dimethyl Sulfide and Methanethiol

    ERIC Educational Resources Information Center

    Chasteen, Thomas G.; Bentley, Ronald

    2004-01-01

    Volatile organic sulfur compounds (VOSCs) have been assigned environmental roles in global warming, acid precipitation, and cloud formation where two important members dimethyl sulfide (CH3)2 S, DMS, and methanethiol, CH3SH, MT, of VOSC group are involved.

  16. ABIOTIC REDOX TRANSFORMATION OF ORGANIC COMPOUNDS AT THE CLAY-WATER INTERFACE

    EPA Science Inventory

    The interactions of clay, water and organic compounds considerably modify the structural and physico-chemical properties of all components and create a unique domain for biological and chemical species in environments. Previous research indicates that the nature and properties of...

  17. INHIBITORY EFFECTS OF VOLATILE ORGANIC COMPOUNDS ON NEURONAL NICOTINIC ACETYLCHOLINE RECEPTORS.

    EPA Science Inventory

    INHIBITORY EFFECTS OF VOLATILE ORGANIC COMPOUNDS ON NEURONAL NICOTINIC ACETYLCHOLINE RECEPTORS.
    A.S. Bale*; P.J. Bushnell; C.A. Meacham; T.J. Shafer
    Neurotoxicology Division, NHEERL, ORD, US Environmental Protection Agency, Research Triangle Park, NC, USA
    Toluene (TOL...

  18. EVALUATION OF CONTROL STRATEGIES FOR VOLATILE ORGANIC COMPOUND IN INDOOR AIR

    EPA Science Inventory

    The Air and Energy Engineering Research Laboratory of the U.S. Environmental Protection Agency (U.S. EPA) conducts and sponsors research on technology to reduce or eliminate emissions of potentially toxic volatile organic compounds (VOCs) from industrial/commercial sources. The r...

  19. Volatile organic compound (VOC) emissions during malting and beer manufacture

    NASA Astrophysics Data System (ADS)

    Gibson, Nigel B.; Costigan, Gavin T.; Swannell, Richard P. J.; Woodfield, Michael J.

    Estimates have been made of the amounts of volatile organic compounds (VOCs) released during different stages of beer manufacture. The estimates are based on recent measurements and plant specification data supplied by manufacturers. Data were obtained for three main manufacturing processes (malting, wort processing and fermentation) for three commercial beer types. Some data on the speciation of emitted compounds have been obtained. Based on these measurements, an estimate of the total unabated VOC emission. from the U.K. brewing industry was calculated as 3.5 kta -1, over 95% of which was generated during barley malting. This value does not include any correction for air pollution control.

  20. 75 FR 74935 - Rescission of Form T-1, Trust Annual Report; Requiring Subsidiary Organization Reporting on the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-01

    .... These provisions include LMRDA Title II financial reporting and disclosure requirements for labor.... The labor organization annual financial reports required by section 201(b) of the Act, 29 U.S.C. 431(b... financial condition and operations for its preceding fiscal year.'' The Form LM-2 Annual Report, the most...

  1. High-efficiency THz modulator based on phthalocyanine-compound organic films

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    He, Ting; Zhang, Bo, E-mail: bzhang@cnu.edu.cn, E-mail: sjl-phy@cnu.edu.cn; Shen, Jingling, E-mail: bzhang@cnu.edu.cn, E-mail: sjl-phy@cnu.edu.cn

    2015-02-02

    We report a high efficiency, broadband terahertz (THz) modulator following a study of phthalocyanine-compound organic films irradiated with an external excitation laser. Both transmission and reflection modulations of each organic/silicon bilayers were measured using THz time-domain and continuous-wave systems. For very low intensities, the experimental results show that AlClPc/Si can achieve a high modulation factor for transmission and reflection, indicating that AlClPc/Si has a superior modulation efficiency compared with the other films (CuPc and SnCl{sub 2}Pc). In contrast, the strong attenuation of the transmitted and reflected THz waves revealed that a nonlinear absorption process takes place at the organic/silicon interface.

  2. Identification of Organic Iodine Compounds and Their Transformation Products in Edible Iodized Salt Using Liquid Chromatography-High Resolution Mass Spectrometry.

    PubMed

    Yun, Lifen; Peng, Yue'e; Chang, Qing; Zhu, Qingxin; Guo, Wei; Wang, Yanxin

    2017-07-05

    The consumption of edible iodized salt is a key strategy to control and eliminate iodine deficiency disorders worldwide. We herein report the identification of the organic iodine compounds present in different edible iodized salt products using liquid chromatography combined with high resolution mass spectrometry. A total of 38 organic iodine compounds and their transformation products (TPs) were identified in seaweed iodine salt from China. Our experiments confirmed that the TPs were generated by the replacement of I atoms from organic iodine compounds with Cl atoms. Furthermore, the organic iodine compound contents in 4 seaweed iodine salt samples obtained from different manufacturers were measured, with significant differences in content being observed. We expect that the identification of organic iodine compounds in salt will be important for estimating the validity and safety of edible iodized salt products.

  3. Process for removing an organic compound from water

    DOEpatents

    Baker, Richard W.; Kaschemekat, Jurgen; Wijmans, Johannes G.; Kamaruddin, Henky D.

    1993-12-28

    A process for removing organic compounds from water is disclosed. The process involves gas stripping followed by membrane separation treatment of the stripping gas. The stripping step can be carried out using one or multiple gas strippers and using air or any other gas as stripping gas. The membrane separation step can be carried out using a single-stage membrane unit or a multistage unit. Apparatus for carrying out the process is also disclosed. The process is particularly suited for treatment of contaminated groundwater or industrial wastewater.

  4. Environmental Aspects of Two Volatile Organic Compound Groundwater Treatment Designs at the Rocky Flats Site - 13135

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Michalski, Casey C.; DiSalvo, Rick; Boylan, John

    2013-07-01

    DOE's Rocky Flats Site in Colorado is a former nuclear weapons production facility that began operations in the early 1950's. Because of releases of hazardous substances to the environment, the federally owned property and adjacent offsite areas were placed on the CERCLA National Priorities List in 1989. The final remedy was selected in 2006. Engineered components of the remedy include four groundwater treatment systems that were installed before closure as CERCLA-accelerated actions. Two of the systems, the Mound Site Plume Treatment System and the East Trenches Plume Treatment System, remove low levels of volatile organic compounds using zero-valent iron media,more » thereby reducing the loading of volatile organic compounds in surface water resulting from the groundwater pathway. However, the zero-valent iron treatment does not reliably reduce all volatile organic compounds to consistently meet water quality goals. While adding additional zero-valent iron media capacity could improve volatile organic compound removal capability, installation of a solar powered air-stripper has proven an effective treatment optimization in further reducing volatile organic compound concentrations. A comparison of the air stripper to the alternative of adding additional zero-valent iron capacity to improve Mound Site Plume Treatment System and East Trenches Plume Treatment System treatment based on several key sustainable remediation aspects indicates the air stripper is also more 'environmentally friendly'. These key aspects include air pollutant emissions, water quality, waste management, transportation, and costs. (authors)« less

  5. Atmospheric PM and volatile organic compounds released from Mediterranean shrubland wildfires

    NASA Astrophysics Data System (ADS)

    Garcia-Hurtado, Elisa; Pey, Jorge; Borrás, Esther; Sánchez, Pilar; Vera, Teresa; Carratalá, Adoración; Alastuey, Andrés; Querol, Xavier; Vallejo, V. Ramon

    2014-06-01

    Wildfires produce a significant release of gases and particles affecting climate and air quality. In the Mediterranean region, shrublands significantly contribute to burned areas and may show specific emission profiles. Our objective was to depict and quantify the primary-derived aerosols and precursors of secondary particulate species released during shrubland experimental fires, in which fire-line intensity values were equivalent to those of moderate shrubland wildfires, by using a number of different methodologies for the characterization of organic and inorganic compounds in both gas-phase and particulate-phase. Emissions of PM mass, particle number concentrations and organic and inorganic PMx components during flaming and smouldering phases were characterized in a field shrubland fire experiment. Our results revealed a clear prevalence of K+ and SO42- as inorganic ions released during the flaming-smouldering processes, accounting for 68-80% of the inorganic soluble fraction. During the residual-smouldering phases, in addition to K+ and SO42-, Ca2+ was found in significant amounts probably due the predominance of re-suspension processes (ashes and soil dust) over other emission sources during this stage. Concerning organic markers, the chromatograms were dominated by phenols, n-alkanals and n-alkanones, as well as by alcohol biomarkers in all the PMx fractions investigated. Levoglucosan was the most abundant degradation compound with maximum emission factors between 182 and 261 mg kg-1 in PM2.5 and PM10 respectively. However, levoglucosan was also observed in significant amounts in the gas-phase. The most representative organic volatile constituents in the smoke samples were alcohols, carbonyls, acids, monocyclic and bicyclic arenes, isoprenoids and alkanes compounds. The emission factors obtained in this study may contribute to the validation and improvement of national and international emission inventories of this intricate and diffuse emission source.

  6. Mechanism of heterogeneous catalytic oxidation of organic compounds to carboxylic acids

    NASA Astrophysics Data System (ADS)

    Andrushkevich, T. V.; Chesalov, Yu A.

    2018-06-01

    The results of studies on the mechanism of heterogeneous catalytic oxidation of organic compounds of different chemical structure to carboxylic acids are analyzed and generalized. The concept developed by Academician G.K.Boreskov, according to which the direction of the reaction is governed by the structure and bond energy of surface intermediates, was confirmed taking the title processes as examples. Quantitative criteria of the bond energies of surface compounds of oxidizable reactants, reaction products and oxygen that determine the selective course of the reaction are presented. The bibliography includes 195 references.

  7. 40 CFR 60.542 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Rubber Tire Manufacturing Industry § 60.542 Standards for volatile organic compounds. (a) On and after... duration of the compliance period: (A) 3,870 kg (8,531 lb) of VOC per 28 days, (B) 4,010 kg (8,846 lb) of VOC per 29 days, (C) 4,150 kg (9,149 lb) of VOC per 30 days, (D) 4,280 kg (9,436 lb) of VOC per 31...

  8. Multifunctional slow-release organic-inorganic compound fertilizer.

    PubMed

    Ni, Boli; Liu, Mingzhu; Lü, Shaoyu; Xie, Lihua; Wang, Yanfang

    2010-12-08

    Multifunctional slow-release organic-inorganic compound fertilizer (MSOF) has been investigated to improve fertilizer use efficiency and reduce environmental pollution derived from fertilizer overdosage. The special fertilizer is based on natural attapulgite (APT) clay used as a matrix, sodium alginate used as an inner coating and sodium alginate-g-poly(acrylic acid-co-acrylamide)/humic acid (SA-g-P(AA-co-AM)/HA) superabsorbent polymer used as an outer coating. The coated multielement compound fertilizer granules were produced in a pan granulator, and the diameter of the prills was in the range of 2.5-3.5 mm. The structural and chemical characteristics of the product, as well as its efficiency in slowing the nutrients release, were examined. In addition, a mathematical model for nutrient release from the fertilizer was applied to calculate the diffusion coefficient D of nutrients in MSOF. The degradation of the SA-g-P(AA-co-AM)/HA coating was assessed by examining the weight loss with incubation time in soil. It is demonstrated that the product prepared by a simple route with good slow-release property may be expected to have wide potential applications in modern agriculture and horticulture.

  9. User's guide for polyethylene-based passive diffusion bag samplers to obtain volatile organic compound concentrations in wells. Part 2, Field tests

    USGS Publications Warehouse

    Vroblesky, Don A.

    2001-01-01

    Diffusion samplers installed in observation wells were found to be capable of yielding representative water samples for chlorinated volatile organic compounds. The samplers consisted of polyethylene bags containing deionized water and relied on diffusion of chlorinated volatile organic compounds through the polyethylene membrane. The known ability of polyethylene to transmit other volatile compounds, such as benzene and toluene, indicates that the samplers can be used for a variety of volatile organic compounds. In wells at the study area, the volatile organic compound concentrations in water samples obtained using the samplers without prior purging were similar to concentrations in water samples obtained from the respective wells using traditional purging and sampling approaches. The low cost associated with this approach makes it a viable option for monitoring large observation-well networks for volatile organic compounds.

  10. Volatile organic compounds detected in the atmosphere of NASA's Biomass Production Chamber

    NASA Technical Reports Server (NTRS)

    Batten, J. H.; Stutte, G. W.; Wheeler, R. M.

    1996-01-01

    Atmospheres of enclosed environments in which 20 m2 stands of wheat, potato, and lettuce were grown were characterized and quantified by gas chromatography-mass spectrometry. A large number (in excess of 90) of volatile organic compounds (VOCs) were identified in the chambers. Twenty eight VOC's were assumed to be of biogenic origin for these were not found in the chamber atmosphere when air samples were analyzed in the absence of plants. Some of the compounds found were unique to a single crop. For example, only 35% of the biogenic compounds detected in the wheat atmosphere were unique to wheat, while 36% were unique to potato and 26% were unique to lettuce. The number of compounds detected in the wheat (20 compounds) atmosphere was greater than that of potato (11) and lettuce (15) and concentration levels of biogenic and non-biogenic VOC's were similar.

  11. Spatial Gradients and Source Apportionment of Volatile Organic Compounds Near Roadways

    EPA Science Inventory

    Concentrations of 55 volatile organic compounds (VOCs) are reported near a highway in Raleigh, NC (traffic volume of approximately 125,000 vehicles/day). Levels of VOCs generally decreased exponentially with perpendicular distance from the roadway 10-100m). The EPA Chemical Mass ...

  12. EXPOSURE TO VOLATILE ORGANIC COMPOUNDS MEASURED IN A SOURCE IMPACTED AIRSHED

    EPA Science Inventory

    A three-year exposure monitoring study is being conducted in a large city in the Midwestern U.S. The study is aimed at determining the factors influencing exposures to air pollutants of outdoor origin, including volatile organic compounds (VOCs) and particulate matter.

  13. SOIL SORPTION OF VOLATILE AND SEMIVOLATILE ORGANIC COMPOUNDS IN A MIXTURE

    EPA Science Inventory

    Studies were conducted to evaluate lipophilicity as a predictor sorption for a mixture of organic compounds with high vapor pressures commonly present at hazardous waste sites. Sorption partition coefficients (Kp) for the mixture of 16 volatile and semivolatile ...

  14. MASTER ANALYTICAL SCHEME FOR ORGANIC COMPOUNDS IN WATER: PART 1. PROTOCOLS

    EPA Science Inventory

    A Master Analytical Scheme (MAS) has been developed for the analysis of volatile (gas chromatographable) organic compounds in water. In developing the MAS, it was necessary to evaluate and modify existing analysis procedures and develop new techniques to produce protocols that pr...

  15. Volatile organic compounds in storm water from a parking lot

    USGS Publications Warehouse

    Lopes, T.J.; Fallon, J.D.; Rutherford, D.W.; Hiatt, M.H.

    2000-01-01

    A mass balance approach was used to determine the most important nonpoint source of volatile organic compounds (VOCs) in storm water from an asphalt parking lot without obvious point sources (e.g., gasoline stations). The parking lot surface and atmosphere are important nonpoint sources of VOCs, with each being important for different VOCs. The atmosphere is an important source of soluble, oxygenated VOCs (e.g., acetone), and the parking lot surface is an important source for the more hydrophobic VOCs (e.g., benzene). VOCs on the parking lot surface appear to be concentrated in oil and grease and organic material in urban particles (e.g., vehicle soot). Except in the case of spills, asphalt does not appear to be an important source of VOCs. The uptake isotherm of gaseous methyl tert-butyl ether on urban particles indicates a mechanism for dry deposition of VOCs from the atmosphere. This study demonstrated that a mass balance approach is a useful means of understanding non-point-source pollution, even for compounds such as VOCs, which are difficult to sample.

  16. Measurement and modelling of oxygenated organic compounds from smoldering combustion of biomass

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McKenzie, L.M.; Richards, G.N.

    Biomass fires emit a myriad of compounds, some of which are toxic and/or globally significant as photochemically reactive, tropospheric trace gases, greenhouse gases and precursors to stratospheric ozone-destroying radicals. 35 oxygenated organic compounds in condensed (-45{degrees}C) smoke from 29 bench scale fires of ponderosa pine sapwood, needles, bark, litter, duff, and humus have been identified and quantified. These fires ranged from flaming to low intensity smoldering. In addition, five low intensity fires of intact ponderosa pine forest floor (litter, duff, and humus) were carried out on a larger scale in a combustion chamber. The condensates were analyzed by gas chromatography/massmore » spectrometry and the gas phase was analyzed by gas chromatography/flame ionization detection. Acetic acid, vinyl acetate and acetol were major condensable emissions. The dependence of oxygenated organic emissions on fuel chemistry and combustion efficiency has been investigated, along with correlations between emissions. Molar emission ratios of individual compounds to CO have been calculated and used to estimate possible exposure levels for wildland firefighters.« less

  17. Cyclodextrin-based microsensor for volatile organic compounds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Swanson, B.I.; Li, D.Q.

    1996-12-31

    The direct covalent attachment of modified {alpha}- and {beta}-cyclodextrin on oxide surfaces has been studied for application in chemical sensors. First, oxide surfaces were treated with a silane coupling layer followed by the addition of cyclodextrin to form a self-assembled monolayer (SAM) of host receptors. Second, the oxide surfaces were reacted with a sol-gel (SG) precursor based on cyclodextrin structure to form a thick film with defined hydrophobic cyclodextrin cavities. The sensing properties of both films (SAM and SG) were examined with surface acoustic wave (SAW) measurement platform. Molecular interactions between an organic guest and a host thin-film on amore » 200 MHZ SAW resonator are being studied as a method of tracking and recognizing the presence of volatile organics. Surface acoustic wave sensors based on the inclusion chemistry of the bucket-type (cyclodextrin) molecules, were capable of detecting volatile organic compounds (VOCs) down to ppb levels. Because the nature of the interactions is moderate but noncovalent, detection of these VOCs was possible using a reversible real-time mode. Pattern recognition with an array of complementary microsensors appears to be a viable approach for identifying and quantifying VOCs. Recent results using optical waveguides for sensor transduction will also be discussed.« less

  18. Sulfate minerals: a problem for the detection of organic compounds on Mars?

    PubMed

    Lewis, James M T; Watson, Jonathan S; Najorka, Jens; Luong, Duy; Sephton, Mark A

    2015-03-01

    The search for in situ organic matter on Mars involves encounters with minerals and requires an understanding of their influence on lander and rover experiments. Inorganic host materials can be helpful by aiding the preservation of organic compounds or unhelpful by causing the destruction of organic matter during thermal extraction steps. Perchlorates are recognized as confounding minerals for thermal degradation studies. On heating, perchlorates can decompose to produce oxygen, which then oxidizes organic matter. Other common minerals on Mars, such as sulfates, may also produce oxygen upon thermal decay, presenting an additional complication. Different sulfate species decompose within a large range of temperatures. We performed a series of experiments on a sample containing the ferric sulfate jarosite. The sulfate ions within jarosite break down from 500 °C. Carbon dioxide detected during heating of the sample was attributed to oxidation of organic matter. A laboratory standard of ferric sulfate hydrate released sulfur dioxide from 550 °C, and an oxygen peak was detected in the products. Calcium sulfate did not decompose below 1000 °C. Oxygen released from sulfate minerals may have already affected organic compound detection during in situ thermal experiments on Mars missions. A combination of preliminary mineralogical analyses and suitably selected pyrolysis temperatures may increase future success in the search for past or present life on Mars.

  19. Sulfate Minerals: A Problem for the Detection of Organic Compounds on Mars?

    PubMed Central

    Watson, Jonathan S.; Najorka, Jens; Luong, Duy; Sephton, Mark A.

    2015-01-01

    Abstract The search for in situ organic matter on Mars involves encounters with minerals and requires an understanding of their influence on lander and rover experiments. Inorganic host materials can be helpful by aiding the preservation of organic compounds or unhelpful by causing the destruction of organic matter during thermal extraction steps. Perchlorates are recognized as confounding minerals for thermal degradation studies. On heating, perchlorates can decompose to produce oxygen, which then oxidizes organic matter. Other common minerals on Mars, such as sulfates, may also produce oxygen upon thermal decay, presenting an additional complication. Different sulfate species decompose within a large range of temperatures. We performed a series of experiments on a sample containing the ferric sulfate jarosite. The sulfate ions within jarosite break down from 500°C. Carbon dioxide detected during heating of the sample was attributed to oxidation of organic matter. A laboratory standard of ferric sulfate hydrate released sulfur dioxide from 550°C, and an oxygen peak was detected in the products. Calcium sulfate did not decompose below 1000°C. Oxygen released from sulfate minerals may have already affected organic compound detection during in situ thermal experiments on Mars missions. A combination of preliminary mineralogical analyses and suitably selected pyrolysis temperatures may increase future success in the search for past or present life on Mars. Key Words: Mars—Life detection—Geochemistry—Organic matter—Jarosite. Astrobiology 15, 247–258. PMID:25695727

  20. Emissions of organic compounds from produced water ponds I: Characteristics and speciation.

    PubMed

    Lyman, Seth N; Mansfield, Marc L; Tran, Huy N Q; Evans, Jordan D; Jones, Colleen; O'Neil, Trevor; Bowers, Ric; Smith, Ann; Keslar, Cara

    2018-04-01

    We measured fluxes of methane, a suite of non-methane hydrocarbons (C2-C11), light alcohols, and carbon dioxide from oil and gas produced water storage and disposal ponds in Utah (Uinta Basin) and Wyoming (Upper Green River Basin) United States during 2013-2016. In this paper, we discuss the characteristics of produced water composition and air-water fluxes, with a focus on flux chamber measurements. In companion papers, we will (1) report on inverse modeling methods used to estimate emissions from produced water ponds, including comparisons with flux chamber measurements, and (2) discuss the development of mass transfer coefficients to estimate emissions and place emissions from produced water ponds in the context of all regional oil and gas-related emissions. Alcohols (made up mostly of methanol) were the most abundant organic compound group in produced water (91% of total volatile organic concentration, with upper and lower 95% confidence levels of 89 and 93%) but accounted for only 34% (28 to 41%) of total organic compound fluxes from produced water ponds. Non-methane hydrocarbons, which are much less water-soluble than methanol and less abundant in produced water, accounted for the majority of emitted organics. C6-C9 alkanes and aromatics dominated hydrocarbon fluxes, perhaps because lighter hydrocarbons had already volatilized from produced water prior to its arrival in storage or disposal ponds, while heavier hydrocarbons are less water soluble and less volatile. Fluxes of formaldehyde and other carbonyls were low (1% (1 to 2%) of total organic compound flux). The speciation and magnitude of fluxes varied strongly across the facilities measured and with the amount of time water had been exposed to the atmosphere. The presence or absence of ice also impacted fluxes. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Organosulfates and organic acids in Arctic aerosols: speciation, annual variation and concentration levels

    NASA Astrophysics Data System (ADS)

    Hansen, A. M. K.; Kristensen, K.; Nguyen, Q. T.; Zare, A.; Cozzi, F.; Nøjgaard, J. K.; Skov, H.; Brandt, J.; Christensen, J. H.; Ström, J.; Tunved, P.; Krejci, R.; Glasius, M.

    2014-02-01

    Sources, composition and occurrence of secondary organic aerosols (SOA) in the Arctic were investigated at Zeppelin Mountain, Svalbard, and Station Nord, northeast Greenland, during the full annual cycle of 2008 and 2010 respectively. We focused on the speciation of three types of SOA tracers: organic acids, organosulfates and nitrooxy organosulfates from both anthropogenic and biogenic precursors, here presenting organosulfate concentrations and compositions during a full annual cycle and chemical speciation of organosulfates in Arctic aerosols for the first time. Aerosol samples were analysed using High Performance Liquid Chromatography coupled to a quadrupole Time-of-Flight mass spectrometer (HPLC-q-TOF-MS). A total of 11 organic acids (terpenylic acid, benzoic acid, phthalic acid, pinic acid, suberic acid, azelaic acid, adipic acid, pimelic acid, pinonic acid, diaterpenylic acid acetate (DTAA) and 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA)), 12 organosulfates and one nitrooxy organosulfate were identified at the two sites. Six out of the 12 organosulfates are reported for the first time. Concentrations of organosulfates follow a distinct annual pattern at Station Nord, where high concentration were observed in late winter and early spring, with a mean total concentration of 47 (±14) ng m-3, accounting for 7 (±2)% of total organic matter, contrary to a considerably lower organosulfate mean concentration of 2 (±3) ng m-3 (accounting for 1 (±1)% of total organic matter) observed during the rest of the year. The organic acids followed the same temporal trend as the organosulfates at Station Nord; however the variations in organic acid concentrations were less pronounced, with a total mean organic acid concentration of 11.5 (±4) ng m-3 (accounting for 1.7 (±0.6)% of total organic matter) in late winter and early spring, and 2.2 (±1) ng m-3 (accounting for 0.9 (±0.4)% of total organic matter) during the rest of the year. At Zeppelin Mountain

  2. Description, Properties, and Degradation of Selected Volatile Organic Compounds Detected in Ground Water--A Review of Selected Literature

    USGS Publications Warehouse

    Lawrence, Stephen J.

    2006-01-01

    This report provides abridged information describing the most salient properties and biodegradation of 27 chlorinated volatile organic compounds detected during ground-water studies in the United States. This information is condensed from an extensive list of reports, papers, and literature published by the U.S. Government, various State governments, and peer-reviewed journals. The list includes literature reviews, compilations, and summaries describing volatile organic compounds in ground water. This report cross-references common names and synonyms associated with volatile organic compounds with the naming conventions supported by the International Union of Pure and Applied Chemistry. In addition, the report describes basic physical characteristics of those compounds such as Henry's Law constant, water solubility, density, octanol-water partition (log Kow), and organic carbon partition (log Koc) coefficients. Descriptions and illustrations are provided for natural and laboratory biodegradation rates, chemical by-products, and degradation pathways.

  3. 2016 Consequence Management Advisory Division's (CMAD) Annual Report

    EPA Pesticide Factsheets

    CMAD annual report for 2016 which covers activities such as radiation task force leaders annual training, national criminal enforcement response team annual training, field technology demonstrations, and a new method to detect perfluorinated compounds.

  4. Emission of volatile organic compounds after land application of cattle manure

    USDA-ARS?s Scientific Manuscript database

    Beef cattle manure can serve as a valuable source of nutrients for crop production. However, emissions of volatile organic compounds (VOCs) following land application may pose an odor nuisance to downwind populations. This study was conducted to evaluate the effects of application method, diet, so...

  5. CHARACTERIZATION OF EMISSIONS OF VOLATILE ORGANIC COMPOUNDS FROM INTERIOR ALKYD PAINT

    EPA Science Inventory

    Alkyd paint continues to be used indoors for application to wood trim, cabinet surfaces, and some kitchen and bathroom walls. Paint may represent a significant source of volatile organic compounds (VOCs) indoors depending on the frequency of use and amount of surface paint. The U...

  6. Advanced Characterization of Semivolatile Organic Compounds Emitted from Biomass Burning

    NASA Astrophysics Data System (ADS)

    Hatch, L. E.; Liu, Y.; Rivas-Ubach, A.; Shaw, J. B.; Lipton, M. S.; Barsanti, K. C.

    2017-12-01

    Biomass burning (BB) emits large amounts of non-methane organic gases (NMOGs) and primary (directly emitted) particulate matter (PM). NMOGs also react in plume to form secondary PM (i.e., SOA) and ozone. BB-PM has been difficult to represent accurately in models used for chemistry and climate predictions, including for air quality and fire management purposes. Much recent research supports that many previously unconsidered SOA precursors exist, including oxidation of semivolatile compounds (SVOCs). Although many recent studies have characterized relatively volatile BB-derived NMOGs and relatively non-volatile particle-phase organic species, comparatively few studies have performed detailed characterization of SVOCs emitted from BB. Here we present efforts to expand the volatility and compositional ranges of compounds measured in BB smoke. In this work, samples of SVOCs in gas and particle phases were collected from 18 fires representing a range of fuel types during the 2016 FIREX fire laboratory campaign; samples were analyzed by two-dimensional gas chromatography with time-of-flight mass spectrometry (GCxGC-TOFMS) and Fourier-transform ion cyclotron resonance mass spectrometry (FTICR-MS). Hundreds of compounds were detectable in both gas and particle phases by GCxGC-TOFMS whereas thousands of peaks were present in the FTICR mass spectra. Data from both approaches highlight that chemical fingerprints of smoke are fuel/burn-dependent. These efforts support our continued research in building the understanding and model representation of BB emissions and BB-derived SOA.

  7. Advanced Characterization of Semivolatile Organic Compounds Emitted from Biomass Burning

    NASA Astrophysics Data System (ADS)

    Hatch, L. E.; Liu, Y.; Rivas-Ubach, A.; Shaw, J. B.; Lipton, M. S.; Barsanti, K. C.

    2016-12-01

    Biomass burning (BB) emits large amounts of non-methane organic gases (NMOGs) and primary (directly emitted) particulate matter (PM). NMOGs also react in plume to form secondary PM (i.e., SOA) and ozone. BB-PM has been difficult to represent accurately in models used for chemistry and climate predictions, including for air quality and fire management purposes. Much recent research supports that many previously unconsidered SOA precursors exist, including oxidation of semivolatile compounds (SVOCs). Although many recent studies have characterized relatively volatile BB-derived NMOGs and relatively non-volatile particle-phase organic species, comparatively few studies have performed detailed characterization of SVOCs emitted from BB. Here we present efforts to expand the volatility and compositional ranges of compounds measured in BB smoke. In this work, samples of SVOCs in gas and particle phases were collected from 18 fires representing a range of fuel types during the 2016 FIREX fire laboratory campaign; samples were analyzed by two-dimensional gas chromatography with time-of-flight mass spectrometry (GCxGC-TOFMS) and Fourier-transform ion cyclotron resonance mass spectrometry (FTICR-MS). Hundreds of compounds were detectable in both gas and particle phases by GCxGC-TOFMS whereas thousands of peaks were present in the FTICR mass spectra. Data from both approaches highlight that chemical fingerprints of smoke are fuel/burn-dependent. These efforts support our continued research in building the understanding and model representation of BB emissions and BB-derived SOA.

  8. Measurement of in-vehicle volatile organic compounds under static conditions.

    PubMed

    You, Ke-wei; Ge, Yun-shan; Hu, Bin; Ning, Zhan-wu; Zhao, Shou-tang; Zhang, Yan-ni; Xie, Peng

    2007-01-01

    The types and quantities of volatile organic compounds (VOCs) inside vehicles have been determined in one new vehicle and two old vehicles under static conditions using the Thermodesorber-Gas Chromatograph/Mass Spectrometer (TD-GC/MS). Air sampling and analysis was conducted under the requirement of USEPA Method TO-17. A room-size, environment test chamber was utilized to provide stable and accurate control of the required environmental conditions (temperature, humidity, horizontal and vertical airflow velocity, and background VOCs concentration). Static vehicle testing demonstrated that although the amount of total volatile organic compounds (TVOC) detected within each vehicle was relatively distinct (4940 microg/m3 in the new vehicle A, 1240 microg/m3 in used vehicle B, and 132 microg/m3 in used vehicle C), toluene, xylene, some aromatic compounds, and various C7-C12 alkanes were among the predominant VOC species in all three vehicles tested. In addition, tetramethyl succinonitrile, possibly derived from foam cushions was detected in vehicle B. The types and quantities of VOCs varied considerably according to various kinds of factors, such as, vehicle age, vehicle model, temperature, air exchange rate, and environment airflow velocity. For example, if the airflow velocity increases from 0.1 m/s to 0.7 m/s, the vehicle's air exchange rate increases from 0.15 h(-1) to 0.67 h(-1), and in-vehicle TVOC concentration decreases from 1780 to 1201 microg/m3.

  9. RT-MATRIX: Measuring Total Organic Carbon by Photocatalytic Oxidation of Volatile Organic Compounds

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Volatile organic compounds (VOCs) inevitably accumulate in enclosed habitats such as the International Space Station and the Crew Exploration Vehicle (CEV) as a result of human metabolism, material off-gassing, and leaking equipment. Some VOCs can negatively affect the quality of the crew's life, health, and performance; and consequently, the success of the mission. Air quality must be closely monitored to ensure a safe living and working environment. Currently, there is no reliable air quality monitoring system that meets NASA's stringent requirements for power, mass, volume, or performance. The ultimate objective of the project -- the development of a Real-Time, Miniaturized, Autonomous Total Risk Indicator System (RT.MATRIX).is to provide a portable, dual-function sensing system that simultaneously determines total organic carbon (TOC) and individual contaminants in air streams.

  10. Recovery of several volatile organic compounds from simulated water samples: Effect of transport and storage

    USGS Publications Warehouse

    Friedman, L.C.; Schroder, L.J.; Brooks, M.G.

    1986-01-01

    Solutions containing volatile organic compounds were prepared in organic-free water and 2% methanol and submitted to two U.S. Geological Survey laboratories. Data from the determination of volatile compounds in these samples were compared to analytical data for the same volatile compounds that had been kept in solutions 100 times more concentrated until immediately before analysis; there was no statistically significant difference in the analytical recoveries. Addition of 2% methanol to the storage containers hindered the recovery of bromomethane and vinyl chloride. Methanol addition did not enhance sample stability. Further, there was no statistically significant difference in results from the two laboratories, and the recovery efficiency was more than 80% in more than half of the determinations made. In a subsequent study, six of eight volatile compounds showed no significant loss of recovery after 34 days.

  11. The effects of ultraviolet light on the degradation of organic compounds: a possible explanation for the absence of organic matter on Mars.

    PubMed

    Oro, J; Holzer, G

    1979-01-01

    The analysis of the top layer of the Martian regolith at the two Viking landing sites did not reveal any indigenous organic compounds. However the existence of such compounds at deeper layers cannot be ruled out. Cosmochemical considerations indicate various potential sources for organic matter on Mars, such as comets and meteorites. Its disappearance from the top layer could be caused by degradation processes on the surface of the planet. Possible destructive agents include ultraviolet light, oxygen and metal oxides. In this study we tested the stability of a sample of the Murchison meteorite and various organic substances which have been detected in carbonaceous chondrites, such as glycine, adenine and naphthalene, to the action of ultraviolet light. The compounds were adsorbed on powdered quartz and on California desert soil and were irradiated in the presence or absence of oxygen. The organic content, before and after irradiation, was measured by carbon elementary analysis, UV-absorption, amino acid analysis or pyrolysis-gas chromatography-mass spectrometry. In the absence of oxygen, adenine and glycine appear to be stable over the given period of irradiation. A definite degradation was noticed in the case of naphthalene and the Murchison meteorite. In the presence of oxygen in amounts comparable to those on Mars all compounds were degraded. The degree of degradation was influenced by the irradiation time, temperature and oxygen content.

  12. [Volatile organic compounds concentrations and sources inside new air-conditioned bus].

    PubMed

    You, Ke-Wei; Ge, Yun-Shan; Qian, Yi-Xin; Liu, Wei; Feng, Bo; Zhang, Yan-Ni; Ning, Zhan-Wu; Hu, Bin; Zhao, Shou-Tang

    2008-05-01

    The distributing profile and concentration level inside new air-conditioned buses with 53 seats have been determined using the method of thermal desorption-capillary GC/MS under vehicle static conditions. Compounds were identified from their mass spectral data by using US National Institute of Standards and Technology (NIST02). The total numbers of identified components were 33 inside buses, including alkenes (15,45.4%), aromatic compounds (9,27.3%), alcohols (4,12.1%), ketones (3,9.1%) and esters (2,6.1%), especially in the range of C6-C10. The top 5 compounds measured inside buses were decane (8.01 mg/m3), 3-methylhexane (7.10 mg/m3), heptane (5.10 mg/m3), isoheptane (4.20 mg/m3) and 1-Methyl-3-ethylbenzene (3.56 mg/m3), and total volatile organic compounds (TVOC) > 52.5 mg/m3. The main sources of in-vehicle hydrocarbons and aromatic compounds comes from cabin components and interior trim materials (e.g., sealants, carpets, adhesives, paints, leather, plastics, PU foam and PE foam) that may retain certain VOCs during manufacturing, and/or emit these compounds over an extended period of time from off-gassing, aging-related breakdown products, heating/cooling and so on.

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

    PubMed

    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.

  14. Biofiltration kinetics for volatile organic compounds (VOCs) and development of a structure-biodegradability relationship

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Govind, R.; Wang, Z.; Bishop, D.F.

    1997-12-31

    In recent years, regulation of hazardous air pollutants under the Clean Air Act and its amendments, has emerged as a major environmental issue. Major sources of volatile organic compounds (VOCs) in air are chemical production plants, manufacturing sites using common solvents, combustion sources, and waste treatment operations, such as waste water treatment plants, vacuum extraction of contaminated soils, and ground water stripping operations. Biofiltration is an emerging technology for treatment of biodegradable volatile organic compounds (VOCs) present in air. In biofiltration, the contaminants are contacted with active microorganisms present either in naturally bioactive materials, such as soil, peat, compost, etc.,more » or immobilized on an inactive support media. Design of biofilters requires information on biodegradation kinetics which controls biofilter size. In this paper, an experimental microbiofilter system is presented which can be used to measure biofiltration kinetics for any volatile organic compound. A mathematical model is used to derive the Monod biokinetic parameters from the experimental data. Finally, a structure-bioactivity relationship is derived for estimating the biofiltration biokinetic parameters for a variety of VOCs.« less

  15. 17 CFR 240.17g-3 - Annual financial reports to be furnished by nationally recognized statistical rating organizations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... furnished by nationally recognized statistical rating organizations. 240.17g-3 Section 240.17g-3 Commodity... Recognized Statistical Rating Organizations § 240.17g-3 Annual financial reports to be furnished by nationally recognized statistical rating organizations. (a) A nationally recognized statistical rating...

  16. 17 CFR 240.17g-3 - Annual financial reports to be furnished by nationally recognized statistical rating organizations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... furnished by nationally recognized statistical rating organizations. 240.17g-3 Section 240.17g-3 Commodity... Recognized Statistical Rating Organizations § 240.17g-3 Annual financial reports to be furnished by nationally recognized statistical rating organizations. (a) A nationally recognized statistical rating...

  17. 76 FR 41086 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Volatile Organic Compound...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-13

    ... Promulgation of Air Quality Implementation Plans; Ohio; Volatile Organic Compound Reinforced Plastic Composites... compound (VOC) emissions from reinforced plastic composites production operations. This rule applies to any facility that has reinforced plastic composites production operations. This rule is approvable because it...

  18. INTERLABORATORY COMPARISON STUDIES FOR CHARACTERIZATION OF ORGANIC COMPOUNDS IN PARTICULATE MATTER

    EPA Science Inventory

    A working group of investigators, who are characterizing and quantifying the organic compounds in particulate matter (PM) as part of the US EPA's PM 2.5 research program and related studies, was established three years ago to advance the quality and comparability of data on the...

  19. Organic compounds assessed in Neuse River water used for public supply near Smithfield, North Carolina, 2002-2005

    USGS Publications Warehouse

    Moorman, Michelle C.

    2012-01-01

    Organic compounds studied in a U.S. Geological Survey (USGS) assessment of water samples from the Neuse River and the public supply system for the Town of Smithfield, North Carolina, generally are manmade and include pesticides, gasoline hydrocarbons, solvents, personal-care and domestic-use products, disinfection by-products, and manufacturing additives. Of the 277 compounds assessed, a total of 113 compounds were detected in samples collected approximately monthly during 2002–2005 at the drinking-water intake for the town's water-treatment plant on the Neuse River. Fifty-two organic compounds were commonly detected (in at least 20 percent of the samples) in source water and (or) finished water. The diversity of compounds detected suggests a variety of sources and uses, including wastewater discharges, industrial, agricultural, domestic, and others. Only once during the study did an organic compound concentration exceed a human-health benchmark (benzo[a]pyrene). A human-health benchmark is a chemical concentration specific to water above which there is a risk to humans, however, benchmarks were available for only 18 of the 42 compounds with detected concentrations greater than 0.1 micrograms per liter. On the basis of this assessment, adverse effects to human health are assumed to be negligible.

  20. A Reconnaissance of selected organic compounds in streams in tribal lands in Central Oklahoma, January-February 2009

    USGS Publications Warehouse

    Becker, Carol J.

    2010-01-01

    The U.S. Geological Survey worked in cooperation with the U.S. Environmental Protection Agency and the Kickapoo Tribe of Oklahoma on two separate reconnaissance projects carried out concurrently. Both projects entailed the use of passive samplers as a sampling methodology to investigate the detection of selected organic compounds at stream sites in jurisdictional areas of several tribes in central Oklahoma during January-February 2009. The focus of the project with the U.S. Environmental Protection Agency was the detection of pesticides and pesticide metabolites using Semipermeable Membrane Devices at five stream sites in jurisdictional areas of several tribes. The project with the Kickapoo Tribe of Oklahoma focused on the detection of pesticides, pesticide metabolites, polycyclic aromatic hydrocarbons, polychlorinated biphenyl compounds, and synthetic organic compounds using Semipermeable Membrane Devices and Polar Organic Chemical Integrative Samplers at two stream sites adjacent to the Kickapoo tribal lands. The seven stream sites were located in central Oklahoma on the Cimarron River, Little River, North Canadian River, Deep Fork, and Washita River. Extracts from SPMDs submerged at five stream sites, in cooperation with the U.S. Environmental Protection Agency, were analyzed for 46 pesticides and 6 pesticide metabolites. Dacthal, a pre-emergent herbicide, was detected at all five sites. Pendimethalin, also a pre-emergent, was detected at one site. The insecticides chlorpyrifos and dieldrin were detected at three sites and p,p'-DDE, a metabolite of the insecticide DDT, also was detected at three sites. SPMDs and POCIS were submerged at the upstream edge and downstream edge of the Kickapoo tribal boundaries. Both sites are downstream from the Oklahoma City metropolitan area and multiple municipal wastewater treatment plants. Extracts from the passive samplers were analyzed for 62 pesticides, 10 pesticide metabolites, 3 polychlorinated biphenyl compounds, 35

  1. Dynamic behavior of semivolatile organic compounds in indoor air

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Loy, Michael David Van

    1998-12-09

    Exposures to a wide range of air pollutants are often dominated by those occurring in buildings because of three factors: 1) most people spend a large fraction of their time indoors, 2) many pollutants have strong indoor sources, and 3) the dilution volume in buildings is generally several orders of magnitude smaller than that of an urban airshed. Semivolatile organic compounds (SVOCS) are emitted by numerous indoor sources, including tobacco combustion, cooking, carpets, paints, resins, and glues, so indoor gasphase concentrations of these compounds are likely to be elevated relative to ambient levels. The rates of uptake and release ofmore » reversibly sorbing SVOCS by indoor materials directly affect both peak concentrations and persistence of the pollutants indoors after source elimination. Thus, accurate predictions of SVOC dynamics in indoor air require an understanding of contaminant sorption on surface materials such as carpet and wallboard. The dynamic behaviors of gas-phase nicotine and phenanthrene were investigated in a 20 ms stainless steel chamber containing carpet and painted wallboard. Each compound was studied independently, first in the empty chamber, then with each sorbent individually, and finally with both sorbents in the chamber.« less

  2. Quantitative Prediction of Solvation Free Energy in Octanol of Organic Compounds

    PubMed Central

    Delgado, Eduardo J.; Jaña, Gonzalo A.

    2009-01-01

    The free energy of solvation, ΔGS0, in octanol of organic compunds is quantitatively predicted from the molecular structure. The model, involving only three molecular descriptors, is obtained by multiple linear regression analysis from a data set of 147 compounds containing diverse organic functions, namely, halogenated and non-halogenated alkanes, alkenes, alkynes, aromatics, alcohols, aldehydes, ketones, amines, ethers and esters; covering a ΔGS0 range from about −50 to 0 kJ·mol−1. The model predicts the free energy of solvation with a squared correlation coefficient of 0.93 and a standard deviation, 2.4 kJ·mol−1, just marginally larger than the generally accepted value of experimental uncertainty. The involved molecular descriptors have definite physical meaning corresponding to the different intermolecular interactions occurring in the bulk liquid phase. The model is validated with an external set of 36 compounds not included in the training set. PMID:19399236

  3. laboratory studies on the uptake of organic compounds by ice crystals

    NASA Astrophysics Data System (ADS)

    Fries, E.; Jaeschke, W.

    2003-04-01

    aluminum pipe. Resulting super cooled droplets are removed by stainless-steel-wool. The carrier gas is mixed outside the ice chamber in various proportions with a defined gas mixture of 60 different organic compounds. This mixture is allowed to flow through the ice chamber at defined pressures and temperatures. The concentrations of the compounds in the gas phase are determined at the inlet and the outlet of the ice chamber by a mobile GC (AirmoVoc1020). Additionally, the amount of adsorbed compounds is determined by a very sensitive method based on solid-phase-micro-extraction (SPME) followed by GC/FID. The resulting sorption coefficients for different gas concentrations are plotted vs the reciprocal of the absolute temperature for all substances. First results dealing with the adsorption properties of the investigated organic compounds.

  4. Pyrolysis of organic compounds in the presence of ammonia The Viking Mars lander site alteration experiment

    NASA Technical Reports Server (NTRS)

    Holzer, G.; Oro, J.

    1977-01-01

    The influence of ammonia on the pyrolysis pattern of selected organic substances sorbed on an inorganic phase was investigated. The thermal degradation products were identified by gas chromatography-mass spectrometry. The feasibility of this technique was tested on a meteoritic sample. All substances examined react with ammonia at the pyrolysis temperature of 500 C, the major products being nitriles and heterocyclic compounds in which nitrogen was incorporated. Based on these results, a model for the non-equilibrium production of organic compounds on Jupiter is discussed. The investigation was performed in connection with the Viking lander molecular analysis. The results obtained indicate that the concentrations of ammonia in the retrorocket fuel exhaust would have been probably too small to produce significant changes in the Martian soil organic compounds if any were found.

  5. Sorption of organic carbon compounds to the fine fraction of surface and Subsurface Soils

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jagadamma, Sindhu; Mayes, Melanie; Zinn, Yuri

    2014-01-01

    Dissolved organic carbon (DOC) transported from the soil surface is stabilized in deeper soil profiles by physicochemical sorption processes. However, it is unclear how different forms of organic carbon (OC) compounds common in soil organic matter interact with soil minerals in the surface (A) and subsurface (B) horizons. We added four compounds (glucose, starch, cinnamic acid and stearic acid) to the silt- and clay-sized fraction (fine fraction) of A and B horizons of eight soils from varying climates (3 temperate, 3 tropical, 1 arctic and 1 sub-arctic). Equilibriumbatch experiments were conducted using 0 to 100 mg C L 1 ofmore » 14C-labeled compounds for 8 h. Sorption parameters (maximum sorption capacity, Qmax and binding coefficient, k) calculated by fitting sorption data to the Langmuir equation showed that Qmax of A and B horizons was very similar for all compounds. Both Qmax and k values were related to sorbate properties, with Qmax being lowest for glucose (20 500 mg kg 1), highest for stearic acid (20,000 200,000 mg kg 1), and intermediate for both cinnamic acid (200 4000 mg kg 1) and starch (400 6000 mg kg 1). Simple linear regression analysis revealed that physicochemical properties of the sorbents influenced the Qmax of cinnamic acid and stearic acid, but not glucose and starch. The sorbent properties did not show predictive ability for binding coefficient k. By using the fine fraction as sorbent, we found that the mineral fractions of A horizons are equally reactive as the B horizons irrespective of soil organic carbon content.« less

  6. Hydrogen isotopic compositions of organic compounds in plants reflect the plant's carbon metabolism

    NASA Astrophysics Data System (ADS)

    Cormier, M. A.; Kahmen, A.; Werner, R. A.

    2015-12-01

    The main factors controlling δ2H of plant organic compounds are generally assumed to be the plant's source water and the evaporative deuterium enrichment of leaf water. Hydrogen isotope analyses of plant compounds from sediments or tree rings are therefore mainly applied to assess hydrological conditions at different spatial and temporal scales. However, the biochemical hydrogen isotope fractionation occurring during biosynthesis of plant organic compounds (ɛbio) also accounts for a large part of the variability observed in the δ2H values. Nevertheless, only few studies have directly addressed the physiological basis of this variability and even fewer studies have thus explored possible applications of hydrogen isotope variability in plant organic compounds for plant physiological research. Here we show two datasets indicating that the plant's carbon metabolism can have a substantial influence on δ2H values of n-alkanes and cellulose. First, we performed a controlled experiment where we forced plants into heterotrophic and autotrophic C-metabolism by growing them under four different light treatments. Second, we assessed the δ2H values of different parasitic heterotrophic plants and their autotrophic host plants. Our two datasets show a systematic shift in ɛbio of up to 80 ‰ depending on the plant's carbon metabolism (heterotrophic or autotrophic). Differences in n-alkane and cellulose δ2H values in plants with autotrophic vs. heterotrophic metabolisms can be explained by different NADPH pools that are used by the plants to build their compounds either with assimilates that originate directly from photosynthesis or from stored carbohydrates. Our results have significant implications for the calibration and interpretation of geological records. More importantly, as the δ2H values reflect the plant's carbon metabolism involved during the tissue formation, our findings highlight the potential of δ2H values as new tool for studying plant and ecosystem carbon

  7. [Study of volatile organic compounds of fresh allium species using headspace combined with surface-enhanced Raman scattering].

    PubMed

    Si, Min-Zhen; Zhang, De-Qing; Liu, Ren-Ming

    2014-09-01

    In order to identify volatile organic compounds of fresh plants at room temperature and avoid sample pretreatment and extractions which can be labor intensive, garlic, Chinese chives and scallion were chopped into pieces. Then some of them were placed in the headspace vial and sealed. The gases were drawn from the vial with a syringe and were injected very slowly into Ag colloids for test using R-3000 portable Raman spectrometer. The spectra of volatile organic compounds of allium species, fresh garlic, Chinese chive and shallot plants were successfully.recorded for the first time. For garlic high intensity bands are present at 307, 399, 569, 711, 1,182, 1,287, 1,397 and 1,622 cm(-1). For Chinese chives the high intensity band is present at 672 cm(-1). Low intensity bands are present at 274, 412, 575, 1,185, 1,289, 1,396, 1,618 cm(-1). For shallot high intensity bands are present at 693 cm(-1). Lower intensity bands are present at 372, 888, 1,023 cm(-1). Low intensity bands are present at 1,088, 1,211 and 1,322 cm(-1). The SERS of diallyl disulfide, allyl methyl sulfide and 1-propanethiol in liquid state and gas state were also obtained. The main volatile organic compound of fresh garlic, Chinese chive and shallot are diallyl disulfide, allyl methyl sulfide and 1-propanethiol respectively, and the volatile organic compound of fresh onion, scallion, shallot and chive are all 1-propanethiol. The presented results illustrate that combining headspace and SERS is a powerful tool for volatile organic compound analysis in fresh plants. The volatile organic compound can be detected in fresh plant samples directly and quickly without extraction.

  8. Emission of intermediate, semi and low volatile organic compounds from traffic and their impact on secondary organic aerosol concentrations over Greater Paris

    NASA Astrophysics Data System (ADS)

    Sartelet, K.; Zhu, S.; Moukhtar, S.; André, M.; André, J. M.; Gros, V.; Favez, O.; Brasseur, A.; Redaelli, M.

    2018-05-01

    Exhaust particle emissions are mostly made of black carbon and/or organic compounds, with some of these organic compounds existing in both the gas and particle phases. Although emissions of volatile organic compounds (VOC) are usually measured at the exhaust, emissions in the gas phase of lower volatility compounds (POAvapor) are not. However, these gas-phase emissions may be oxidised after emission and enhance the formation of secondary organic aerosols (SOA). They are shown here to contribute to most of the SOA formation in Central Paris. POAvapor emissions are usually estimated from primary organic aerosol emissions in the particle phase (POA). However, they could also be estimated from VOC emissions for both gasoline and diesel vehicles using previously published measurements from chamber measurements. Estimating POAvapor from VOC emissions and ageing exhaust emissions with a simple model included in the Polyphemus air-quality platform compare well to measurements of SOA formation performed in chamber experiments. Over Greater Paris, POAvapor emissions estimated using POA and VOC emissions are compared using the HEAVEN bottom-up traffic emissions model. The impact on the simulated atmospheric concentrations is then assessed using the Polyphemus/Polair3D chemistry-transport model. Estimating POAvapor emissions from VOC emissions rather than POA emissions lead to lower emissions along motorway axes (between -50% and -70%) and larger emissions in urban areas (up to between +120% and +140% in Central Paris). The impact on total organic aerosol concentrations (gas plus particle) is lower than the impact on emissions: between -8% and 25% along motorway axes and in urban areas respectively. Particle-phase organic concentrations are lower when POAvapor emissions are estimated from VOC than POA emissions, even in Central Paris where the total organic aerosol concentration is higher, because of different assumptions on the emission volatility distribution, stressing the

  9. Radiocarbon evidence for a naturally produced, bioaccumulating halogenated organic compound.

    PubMed

    Reddy, Christopher M; Xu, Li; O'Neil, Gregory W; Nelson, Robert K; Eglinton, Timothy I; Faulkner, D John; Norstrom, Ross; Ross, Peter S; Tittlemier, Sheryl A

    2004-04-01

    Halogenated organic compounds (HOCs) such as 1,1'-dimethyl-3,3',4,4'-tetrabromo-5,5'-dichloro-2,2'-bipyrrole (DBP-Br4Cl2) and heptachloro-1'-methyl-1,2'-bipyrrole (Q1) have been detected worldwide, sometimes at high levels in Antarctic air, seabird eggs, the blubber of marine mammals, and, most notably, even human milk. To date, it has been difficult to determine whether these compounds are natural products or derived from industrial synthesis. Molecular-level 14C analysis of these compounds is particularly appealing because most industrial compounds are manufactured from petrochemicals (14C-free) and natural compounds should have "modern" or "contemporary" 14C levels. To investigate the source of DBP-Br4Cl2, we isolated 600 microg of this compound (150 microg of carbon) from marine animal extracts by employing gel permeation chromatography, Florisil column chromatography, and two-dimensional preparative capillary gas chromatography. The purified DBP-Br4Cl2 was split into two samples (75 microg of carbon each) and analyzed by accelerator mass spectrometry for 14C content. The delta14C values were -449 percent per thousand and -467 percent per thousand, corresponding to conventional 14C ages of 4740 and 5000 years before present (BP), respectively. The presence of detectable 14C in the DBP-Br4Cl2 strongly points to at least a natural or biogenic source. However, these delta14C values for DBP-Br4Cl2 are more depleted than expected for a recently synthesized natural product. Several explanations are discussed, but additional samples

  10. 40 CFR 60.542a - Alternate standard for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for the Rubber Tire Manufacturing Industry § 60.542a Alternate standard for volatile organic compounds. (a) On and after the date on which the initial performance test, required by § 60.8, is completed, but no...

  11. Development of sampling method and chromatographic analysis of volatile organic compounds emitted from human skin.

    PubMed

    Grabowska-Polanowska, Beata; Miarka, Przemysław; Skowron, Monika; Sułowicz, Joanna; Wojtyna, Katarzyna; Moskal, Karolina; Śliwka, Ireneusz

    2017-10-01

    The studies on volatile organic compounds emitted from skin are an interest for chemists, biologists and physicians due to their role in development of different scientific areas, including medical diagnostics, forensic medicine and the perfume design. This paper presents a proposal of two sampling methods applied to skin odor collection: the first one uses a bag of cellulose film, the second one, using cellulose sachets filled with active carbon. Volatile organic compounds were adsorbed on carbon sorbent, removed via thermal desorption and analyzed using gas chromatograph with mass spectrometer. The first sampling method allowed identification of more compounds (52) comparing to the second one (30). Quantitative analyses for acetone, butanal, pentanal and hexanal were done. The skin odor sampling method using a bag of cellulose film, allowed the identification of many more compounds when compared with the method using a sachet filled with active carbon.

  12. Prospects for reconstructing paleoenvironmental conditions from organic compounds in polar snow and ice

    USGS Publications Warehouse

    Giorio, Chiara; Kehrwald, Natalie; Barbante, Carlo; Kalberer, Markus; King, Amy C.F.; Thomas, Elizabeth R.; Wolff, Eric W.; Zennaro, Piero

    2018-01-01

    Polar ice cores provide information about past climate and environmental changes over periods ranging from a few years up to 800,000 years. The majority of chemical studies have focused on determining inorganic components, such as major ions and trace elements as well as on their isotopic fingerprint. In this paper, we review the different classes of organic compounds that might yield environmental information, discussing existing research and what is needed to improve knowledge. We also discuss the problems of sampling, analysis and interpretation of organic molecules in ice. This review highlights the great potential for organic compounds to be used as proxies for anthropogenic activities, past fire events from different types of biomass, terrestrial biogenic emissions and marine biological activity, along with the possibility of inferring past temperature fluctuations and even large-scale climate variability. In parallel, comprehensive research needs to be done to assess the atmospheric stability of these compounds, their ability to be transported long distances in the atmosphere, and their stability in the archive in order to better interpret their fluxes in ice cores. In addition, specific decontamination procedures, analytical methods with low detection limits (ng/L or lower), fast analysis time and low sample requests need to be developed in order to ensure a good time resolution in the archive.

  13. Prospects for reconstructing paleoenvironmental conditions from organic compounds in polar snow and ice

    NASA Astrophysics Data System (ADS)

    Giorio, Chiara; Kehrwald, Natalie; Barbante, Carlo; Kalberer, Markus; King, Amy C. F.; Thomas, Elizabeth R.; Wolff, Eric W.; Zennaro, Piero

    2018-03-01

    Polar ice cores provide information about past climate and environmental changes over periods ranging from a few years up to 800,000 years. The majority of chemical studies have focused on determining inorganic components, such as major ions and trace elements as well as on their isotopic fingerprint. In this paper, we review the different classes of organic compounds that might yield environmental information, discussing existing research and what is needed to improve knowledge. We also discuss the problems of sampling, analysis and interpretation of organic molecules in ice. This review highlights the great potential for organic compounds to be used as proxies for anthropogenic activities, past fire events from different types of biomass, terrestrial biogenic emissions and marine biological activity, along with the possibility of inferring past temperature fluctuations and even large-scale climate variability. In parallel, comprehensive research needs to be done to assess the atmospheric stability of these compounds, their ability to be transported long distances in the atmosphere, and their stability in the archive in order to better interpret their fluxes in ice cores. In addition, specific decontamination procedures, analytical methods with low detection limits (ng/L or lower), fast analysis time and low sample requests need to be developed in order to ensure a good time resolution in the archive.

  14. Process for the solvent extraction for the radiolysis and dehalogenation of halogenated organic compounds in soils, sludges, sediments and slurries

    DOEpatents

    Golden, Jeffry

    2007-02-13

    A process of extracting halogenated organic compounds, and particularly PCBs, from soil, sediment, slurry, sludge and dehalogenating the compounds contacts a contaminated soil sample with an extraction medium of a mixture of an alkane and a water miscible alcohol. The organic compounds dissolve in the extraction medium which is separated from the soil by passing water upwardly through the soil. The extraction medium floats to the surface of the water and is separated. Thereafter, the extraction medium containing the halogenated organic contaminants is subjected to ionizing radiation to radiolytically dehalogenate the compounds.

  15. Process for the solvent extraction for the radiolysis and dehalogenation of halogenated organic compounds in soils, sludges, sediments and slurries

    DOEpatents

    Mincher, Bruce J.; Curry, Randy Dale; Clevenger, Thomas E.; Golden, Jeffry

    2003-05-27

    A process of extracting halogenated organic compounds, and particularly PCBs, from soil, sediment, slurry, sludge and dehalogenating the compounds contacts a contaminated soil sample with an extraction medium of a mixture of an alkane and a water miscible alcohol. The organic compounds dissolve in the extraction medium which is separated from the soil by passing water upwardly through the soil. The extraction medium floats to the surface of the water and is separated. Thereafter, the extraction medium containing the halogenated organic contaminants is subjected to ionizing radiation to radiolytically dehalogenate the compounds.

  16. Process for the solvent extraction for the radiolysis and dehalogenation of halogenated organic compounds in soils, sludges, sediments and slurries

    DOEpatents

    Mincher, Bruce J.; Curry, Randy Dale; Clevenger, Thomas E.; Golden, Jeffry

    2000-01-01

    A process of extracting halogenated organic compounds, and particularly PCBs, from soil, sediment, slurry, sludge and dehalogenating the compounds contacting a contaminated soil sample with an extraction medium of a mixture of an alkane and a water miscible alcohol. The organic compounds dissolve in the extraction medium which is separated from the soil by passing water upwardly through the soil. The extraction medium floats to the surface of the water and is separated. Thereafter, the extraction medium containing the halogenated organic contaminants is subjected to ionizing radiation to radiolytically dehalogenate the compounds.

  17. Ionic liquids as an electrolyte for the electro synthesis of organic compounds.

    PubMed

    Kathiresan, Murugavel; Velayutham, David

    2015-12-25

    The use of ionic liquids (ILs) as a solvent and an electrolyte for electro organic synthesis has been reviewed. To date several ILs exist, however the ILs based on tetraalkylammonium, pyrrolidinium, piperidinium and imidazolium cations with BF4(-), PF6(-), and TFSI anions have been widely used and explored the most. Electro organic synthesis in ionic liquid media leading to the synthesis of a wide range of organic compounds has been discussed. Anodic oxidation or cathodic reduction will generate radical cation or anion intermediates, respectively. These radicals can undergo self coupling or coupling with other molecules yielding organic compounds of interest. The cation of the IL is known to stabilize the radical anion extensively. This stabilization effect has a specific impact on the electrochemical CO2 reduction and coupling to various organics. The relative stability of the intermediates in IL leads to the formation of specific products in higher yields. Electrochemical reduction of imidazolium or thiazolium based ILs generates N-heterocyclic carbenes that have been shown to catalyze a wide range of base or nucleophile catalyzed organic reactions in IL media, an aspect that falls into the category of organocatalysis. Electrochemical fluorination or selective electrochemical fluorination is another fascinating area that delivers selectively fluorinated organic products in Et3N·nHF or Et4NF·nHF adducts (IL) via anodic oxidation. Oxidative polymerization in ILs has been explored the most; although morphological changes were observed compared to the conventional methods, polymers were obtained in good yields and in some cases ILs were used as dopants to improve the desired properties.

  18. Hydrophobization potential of organic compounds deriving from olive oil production waste water

    NASA Astrophysics Data System (ADS)

    Egerer, Sina E.; Bandow, Nicole; Marschner, Bernd; Schaumann, Gabriele E.

    2010-05-01

    Olive oil production waste water (OPWW) is rich in dissolved organic carbon and nutrients (e.g. potassium). In order to use it as organic fertilizer, small-scale and family run olive oil production farms in Israel and Palestine often discharge it directly onto agricultural land without any previous treatment. One unwanted side effect that can be observed is the development of soil water repellency (SWR) which is probably induced by amphiphilic substances. Previous studies on the composition of OPWW have shown that it contains oil components such as phenols, fats and large-molecular organic compounds (e.g. Gonzalezvila et al., 1995), some of which have been reported to induce water repellency on soil mineral surfaces (e.g. Ma'shum et al., 1988; Leelamanie and Karube, 2007). For prioritization of compounds the individual hydrophobization potential of 16 common OPWW components was systematically evaluated using the sessile drop and the Wilhelmy plate method. Acid-washed sand was taken as model soil mineral material. In a batch experiment OPWW samples from Israel and Palestine were applied to sand and two different soils in order to investigate their hydrophobization potential under different temperature and humidity conditions. To facilitate the identification of the chemicals responsible for inducing SWR, a fractionation procedure was applied to fraction the OPWW samples using solvents of different polarity. The prioritized compounds were analyzed by GC-MS. First results of this identification will be presented as well.

  19. MODELING OF MULTICOMPONENT PERVAPORATION FOR REMOVAL OF VOLATILE ORGANIC COMPOUNDS FROM WATER

    EPA Science Inventory

    A resistance-in-series model was used to study the pervaporation of multiple volatile organic compounds (VOCs)-water mixtures. Permeation experiments were carried out for four membranes: poly(dimethylsiloxane) (PDMS), polyether-block-polyamides (PEBA), polyurethane (PUR) and sil...

  20. Metals, pesticides, and semivolatile organic compounds in sediment in Valley Forge National Historical Park, Montgomery County, Pennsylvania

    USGS Publications Warehouse

    Reif, Andrew G.; Sloto, Ronald A.

    1997-01-01

    The Schuylkill River flows through Valley Forge National Historical Park in Lower Providence and West Norriton Townships in Montgomery County, Pa. The concentration of selected metals, pesticides, semivolatile organic compounds, and total carbon in stream-bottom sediments from Valley Forge National Historical Park were determined for samples collected once at 12 sites in and around the Schuylkill River.Relatively low concentrations of arsenic, chromium, copper, and lead were detected in all samples. The concentrations of these metals are similar to concentrations in other stream-bottom sediment samples collected in the region. The concentrations of iron, manganese, and zinc were elevated in samples from four sites in the Schuylkill River, and the concentration of mercury was elevated in a sample from an impoundment along the river.The organophosphorus insecticide diazinon was detected in relatively low concentrations in half of the 12 samples analyzed. The organo-chlorine insecticide DDE was detected in all 12 samples analyzed; dieldrin was detected in 10 samples, chlordane, DDD, and DDT were detected in 9 samples, and heptachlor epoxide was detected in one sample. The concentrations of organo-chlorine and organophosphorus insecticides were relatively low and similar to concentrations in samples collected in the region.Detectable concentrations of 17 semivolatile organic compounds were measured in the 12 samples analyzed. The most commonly detected compounds were fluoranthene, phenanthrene, and pyrene. The maximum concentration detected was 4,800 micrograms per kilogram of phenanthrene. The highest concentrations of compounds were detected in Lamb Run, a small tributary to the Schuylkill River with headwaters in an industrial corporate center. The concentration of compounds in the Schuylkill River below Lamb Run is higher than the Schuylkill River above Lamb Run, indicating that sediment from Lamb Run is increasing the concentration of semivolatile organic

  1. Study of Biogenic Volatile Organic Compounds at the French Guiana Tropical Forest

    NASA Astrophysics Data System (ADS)

    Corain Lopes, P.; Guenther, A. B.; Turnipseed, A.; Burban, B.; Bonal, D.; Serca, D.; Emmons, L. K.; Bustillos, J. W.

    2012-12-01

    Biogenic volatile organic compound (BVOCs) emissions play an important role in regional air quality and global atmospheric chemistry. In addition, these natural VOC emissions serve important biological functions including attracting and repelling pollinators and herbivores. Some biological organisms use ambient air as a communication medium and the oxidation of these compounds brings about the concentration gradients sensed by insects and other organisms. Isoprene is the predominant BVOC emitted by vegetation and tropical forests are the dominant global source. This compound is very reactive in the atmosphere and contributes to the reactions that control tropospheric oxidant concentrations and thus the concentrations and lifetimes of longer-lived species. This paper presents a study of isoprene and some other significant BVOCs such as α-pinene, β-pinene, limonene, e-β ocimene and longifolene, measured at the Paracou Tower located in a wet tropical forest in Cayenne, French Guiana, during the year of 2011, using the Relaxed Eddy Accumulation technique at 30 meters high above the canopy. The results show a lower concentration of isoprene during the month of February and March which correspond to the wet season with an average of 0,545 μg/m3 and 0,341 μg/m3, respectively with a slight increase in middle April which is a period of transition between wet and dry and a higher concentration later in mid-June which corresponds to the transition from wet to dry season (Figure 1). The same behavior was observed for α-pinene with higher concentrations for the same periods as isoprene however with a smaller increase. All the other compounds had concentrations below 1 μg/m3 during the whole year. The monoterpene, e-β ocimene, was observed and is known as a stress compound but the vegetation at the site did not face any known severe stress condition such as excessive drought or flooding. Concerning the fluxes, the results showed that just a small amount of BVOCs were

  2. New Linear Partitioning Models Based on Experimental Water: Supercritical CO2 Partitioning Data of Selected Organic Compounds.

    PubMed

    Burant, Aniela; Thompson, Christopher; Lowry, Gregory V; Karamalidis, Athanasios K

    2016-05-17

    Partitioning coefficients of organic compounds between water and supercritical CO2 (sc-CO2) are necessary to assess the risk of migration of these chemicals from subsurface CO2 storage sites. Despite the large number of potential organic contaminants, the current data set of published water-sc-CO2 partitioning coefficients is very limited. Here, the partitioning coefficients of thiophene, pyrrole, and anisole were measured in situ over a range of temperatures and pressures using a novel pressurized batch-reactor system with dual spectroscopic detectors: a near-infrared spectrometer for measuring the organic analyte in the CO2 phase and a UV detector for quantifying the analyte in the aqueous phase. Our measured partitioning coefficients followed expected trends based on volatility and aqueous solubility. The partitioning coefficients and literature data were then used to update a published poly parameter linear free-energy relationship and to develop five new linear free-energy relationships for predicting water-sc-CO2 partitioning coefficients. A total of four of the models targeted a single class of organic compounds. Unlike models that utilize Abraham solvation parameters, the new relationships use vapor pressure and aqueous solubility of the organic compound at 25 °C and CO2 density to predict partitioning coefficients over a range of temperature and pressure conditions. The compound class models provide better estimates of partitioning behavior for compounds in that class than does the model built for the entire data set.

  3. New Linear Partitioning Models Based on Experimental Water: Supercritical CO 2 Partitioning Data of Selected Organic Compounds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Burant, Aniela; Thompson, Christopher; Lowry, Gregory V.

    2016-05-17

    Partitioning coefficients of organic compounds between water and supercritical CO2 (sc-CO2) are necessary to assess the risk of migration of these chemicals from subsurface CO2 storage sites. Despite the large number of potential organic contaminants, the current data set of published water-sc-CO2 partitioning coefficients is very limited. Here, the partitioning coefficients of thiophene, pyrrole, and anisole were measured in situ over a range of temperatures and pressures using a novel pressurized batch reactor system with dual spectroscopic detectors: a near infrared spectrometer for measuring the organic analyte in the CO2 phase, and a UV detector for quantifying the analyte inmore » the aqueous phase. Our measured partitioning coefficients followed expected trends based on volatility and aqueous solubility. The partitioning coefficients and literature data were then used to update a published poly-parameter linear free energy relationship and to develop five new linear free energy relationships for predicting water-sc-CO2 partitioning coefficients. Four of the models targeted a single class of organic compounds. Unlike models that utilize Abraham solvation parameters, the new relationships use vapor pressure and aqueous solubility of the organic compound at 25 °C and CO2 density to predict partitioning coefficients over a range of temperature and pressure conditions. The compound class models provide better estimates of partitioning behavior for compounds in that class than the model built for the entire dataset.« less

  4. Challenges and solutions for biofiltration of hydrophobic volatile organic compounds.

    PubMed

    Cheng, Yan; He, Huijun; Yang, Chunping; Zeng, Guangming; Li, Xiang; Chen, Hong; Yu, Guanlong

    2016-11-01

    Volatile organic compounds (VOCs) emitted to the environment highly probably result in ecological and health risks. Many biotechnologies for waste gases containing hydrophobic VOCs have been developed in recent years. However, these biological processes usually exhibit poor removal performances for hydrophobic VOCs due to the low bioavailability. This review presents an overview of enhanced removal of hydrophobic VOCs in biofilters. Mechanisms and problems relevant to the biological removal of hydrophobic VOCs are reviewed, and then solutions including the addition of surfactants, application of fungal biocatalysts, biofiltration with pretreatment, innovative bioreactors and utilization of hydrophilic compounds are discussed in detail. Future research needs are also proposed. This review provides new insights into hydrophobic VOC removal by biofiltration. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. The availability of dissolved organic phosphorus compounds to marine phytoplankton

    NASA Astrophysics Data System (ADS)

    Hua-Sheng, Hong; Hai-Li, Wang; Bang-Qin, Huang

    1995-06-01

    The availability of three dissolved organic phosphorus (DOP) compounds as nutrient sources for experimental culture of three algae was studied. Results indicated that these compounds could be utilized by algae, and that dissolved inorganic phosphorus (DIP) was first to be uptaken when various forms of phosphorus (DIP and DOP) co-existed. Dicrateria zhanjiangensis' uptake of sodium glycerophosphate was faster than that of D-ribose-5-phosphate. The increase of sodium glycerophosphate had little effect on the maximum uptake rate( V max) of Chlorella sp., but increased the semisaturation constant( K s) remarkably; the photosynthesis rates(PR) of Dicrateria zhanjiangensis and Chlorella sp. were rarely affected by using various forms of phosphorus in the culture experiments. The possible DOP pathways utilized by algae are discussed.

  6. Production of extremely low volatile organic compounds from biogenic emissions: Measured yields and atmospheric implications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jokinen, Tuija; Berndt, Torsten; Makkonen, Risto

    2015-06-09

    Extremely low volatility organic compounds (ELVOC) are suggested to promote aerosol particle formation and cloud condensation nuclei (CCN) production in the atmosphere. We show that the capability of biogenic VOC (BVOC) to produce ELVOC depends strongly on their chemical structure and relative oxidant levels. BVOC with an endocyclic double bond, representative emissions from, e.g., boreal forests, efficiently produce ELVOC from ozonolysis. Compounds with exocyclic double bonds or acyclic compounds including isoprene, emission representative of the tropics, produce minor quantities of ELVOC, and the role of OH radical oxidation is relatively larger. Implementing these findings into a global modeling framework showsmore » that detailed assessment of ELVOC production pathways is crucial for understanding biogenic secondary organic aerosol and atmospheric CCN formation.« less

  7. EVALUATION USING AN ORGANOPHILIC CLAY TO CHEMICALLY STABILIZE WASTE CONTAINING ORGANIC COMPOUNDS

    EPA Science Inventory

    A modified clay (organophilic) was utilized to evaluate the potential for chemically stabilizing a waste containing organic compounds. hemical bonding between the binder and the contaminants was indicated. eachate testing also indicated strong binding. Copy available at NTIS as ...

  8. Biodesulfurization of refractory organic sulfur compounds in fossil fuels.

    PubMed

    Soleimani, Mehran; Bassi, Amarjeet; Margaritis, Argyrios

    2007-01-01

    The stringent new regulations to lower sulfur content in fossil fuels require new economic and efficient methods for desulfurization of recalcitrant organic sulfur. Hydrodesulfurization of such compounds is very costly and requires high operating temperature and pressure. Biodesulfurization is a non-invasive approach that can specifically remove sulfur from refractory hydrocarbons under mild conditions and it can be potentially used in industrial desulfurization. Intensive research has been conducted in microbiology and molecular biology of the competent strains to increase their desulfurization activity; however, even the highest activity obtained is still insufficient to fulfill the industrial requirements. To improve the biodesulfurization efficiency, more work is needed in areas such as increasing specific desulfurization activity, hydrocarbon phase tolerance, sulfur removal at higher temperature, and isolating new strains for desulfurizing a broader range of sulfur compounds. This article comprehensively reviews and discusses key issues, advances and challenges for a competitive biodesulfurization process.

  9. Reconnaissance of Organic Wastewater Compounds at a Concentrated Swine Feeding Operation in the North Carolina Coastal Plain, 2008

    USGS Publications Warehouse

    Harden, Stephen L.

    2009-01-01

    Water-quality and hydrologic data were collected during 2008 to examine the occurrence of organic wastewater compounds at a concentrated swine feeding operation located in the North Carolina Coastal Plain. Continuous groundwater level and stream-stage data were collected at one monitoring well and one stream site, respectively, throughout 2008. One round of environmental and quality-control samples was collected in September 2008 following a period of below-normal precipitation and when swine waste was not being applied to the spray fields. Samples were collected at one lagoon site, seven shallow groundwater sites, and one surface-water site for analysis of 111 organic wastewater compounds, including household, industrial, and agricultural-use compounds, sterols, pharmaceutical compounds, hormones, and antibiotics. Analytical data for environmental samples collected during the study provide preliminary information on the occurrence of organic wastewater compounds in the lagoon-waste source material, groundwater beneath fields that receive spray applications of the lagoon wastes, and surface water in the tributary adjacent to the site. Overall, 28 organic wastewater compounds were detected in the collected samples, including 11 household, industrial, and agricultural-use compounds; 3 sterols; 2 pharmaceutical compounds; 5 hormones; and 7 antibiotics. The lagoon sample had the greatest number (20) and highest concentrations of compounds compared to groundwater and surface-water samples. The antibiotic lincomycin had the maximum detected concentration (393 micrograms per liter) in the lagoon sample. Of the 11 compounds identified in the groundwater and surface-water samples, all with reported concentrations less than 1 microgram per liter, only lincomycin identified in groundwater at 1 well and 3-methyl-1H-indole and indole identified in surface water at 1 site also were identified in the lagoon waste material.

  10. Biotoxicity and bioavailability of hydrophobic organic compounds solubilized in nonionic surfactant micelle phase and cloud point system.

    PubMed

    Pan, Tao; Liu, Chunyan; Zeng, Xinying; Xin, Qiao; Xu, Meiying; Deng, Yangwu; Dong, Wei

    2017-06-01

    A recent work has shown that hydrophobic organic compounds solubilized in the micelle phase of some nonionic surfactants present substrate toxicity to microorganisms with increasing bioavailability. However, in cloud point systems, biotoxicity is prevented, because the compounds are solubilized into a coacervate phase, thereby leaving a fraction of compounds with cells in a dilute phase. This study extends the understanding of the relationship between substrate toxicity and bioavailability of hydrophobic organic compounds solubilized in nonionic surfactant micelle phase and cloud point system. Biotoxicity experiments were conducted with naphthalene and phenanthrene in the presence of mixed nonionic surfactants Brij30 and TMN-3, which formed a micelle phase or cloud point system at different concentrations. Saccharomyces cerevisiae, unable to degrade these compounds, was used for the biotoxicity experiments. Glucose in the cloud point system was consumed faster than in the nonionic surfactant micelle phase, indicating that the solubilized compounds had increased toxicity to cells in the nonionic surfactant micelle phase. The results were verified by subsequent biodegradation experiments. The compounds were degraded faster by PAH-degrading bacterium in the cloud point system than in the micelle phase. All these results showed that biotoxicity of the hydrophobic organic compounds increases with bioavailability in the surfactant micelle phase but remains at a low level in the cloud point system. These results provide a guideline for the application of cloud point systems as novel media for microbial transformation or biodegradation.

  11. Distribution of volatile organic compounds over a semiconductor Industrial Park in Taiwan.

    PubMed

    Chiu, Kong-Hwa; Wu, Ben-Zen; Chang, Chih-Chung; Sree, Usha; Lo, Jiunn-Guang

    2005-02-15

    This study examined volatile organic compounds (VOC) concentration in ambient air collected during the years 2000--2003 at several different locations of Hsinchu Science-based Industrial Park (HSIP) in Taiwan. A canister automated GC-MS system analyzed the volatile organics in ambient air grasp samples according to T0-15 method. Oxygenated volatiles were the most abundant VOC detected in HSIP followed by aromatics that are commonly used as solvents in the semiconductor industries. The major components measured in the ambient air are 2-propanol (29-135 ppbv), acetone (12-164 ppbv), benzene (0.7-1.7 ppbv), and toluene (13-20 ppbv). At some of the sampling locations, odorous compounds such as carbon disulfide and dimethyl sulfide levels exceed threshold values. The estimated toluene/benzene ratio is very high at most of the sites. However, the total amount of VOC is reduced over the years from 2000 to 2003 due to strict implementation on use and discharge of solvents in industries. There exists no definite seasonal pattern for sporadic occurrence of high levels of some of the volatile organics. Stagnant weather conditions with low wind speeds aid accumulation of toxic species at ground level. The results entail that hi-tech semiconductor industries are still a potential source for harmful organic substances to surrounding microenvironment.

  12. Contribution of synthetic and naturally occurring organobromine compounds to bromine mass in marine organisms.

    PubMed

    Wan, Yi; Jones, Paul D; Wiseman, Steve; Chang, Hong; Chorney, Dave; Kannan, Kurunthachalam; Zhang, Kun; Hu, Jian-Ying; Khim, Jong Seong; Tanabe, Shinsuke; Lam, Michael H W; Giesy, John P

    2010-08-15

    An extraction, separation, and purification method was developed for the identification and quantification of total bromine (TBr), extractable organobromine (EOBr), and five classes of identified EOBrs. Instrumental neutron activation analysis (INAA) was utilized to quantify EOBr and TBr. The method was then applied to liver samples of tuna, albatross, and polar bear collected from remote marine locations. Polybrominated biphenyls (PBBs), polybrominated diphenyl ethers (PBDEs), bromophenols (BRPs), hydroxylated (OH-) and methoxylated (MeO-) PBDEs were analyzed as identified EOBr. The majority of the bromine in these marine organisms was nonextractable or inorganic, with EOBr accounting for 10-28% of the TBr. Of the identified EOBr, in tuna and albatross, naturally occurring compounds, including MeO-PBDEs, OH-PBDEs, and BPRs, were prevalent. However, the identifiable EOBr in polar bears consisted primarily of synthetic compounds, including PBDEs and PBBs. Overall, 0.08-0.11% and 0.008-0.012% of EOBr and TBr, respectively, were identified. The proportion of EOBr that was identified in marine organisms was relatively small compared to the proportions for organofluorine and organochlorine compounds. This could be related to the great diversity of naturally occurring organobromine compounds in the environment. Naturally occurring brominated fatty acids were estimated to be the predominant compounds in the EOBr fraction.

  13. Evaluation of organic compounds and trace elements in Amazon Creek Basin, Oregon, September 1990

    USGS Publications Warehouse

    Rinella, F.A.

    1993-01-01

    Water and bottom sediment were collected from Amazon Creek, Oregon during a summer low-flow condition and analyzed for different classes of organic compounds, including many from the U.S. Environmental Protection Agency's priority pollutant list. Bottom sediment also was analyzed for trace elements typically associated with urban runoff. Trace-element concentrations in the less than 63 micrometer fraction of Amazon Creek bottom-sediment samples were compared with baseline concentrations (expected 95 percent confidence range) for soils from the Western United States and with concen- trations found in bottom sediment from the Willamette River Basin. Total-digestion concentrations of antimony, arsenic, cadmium, chromium, cobalt, copper, lead, manganese, mercury, nickel, silver, titanium, and zinc were enriched at some or all sites sampled. Whole-water samples from some sites contained concentrations of several chlorophenoxy-acid herbicides, the organophosphorus insecticide diazinon, and several semivolatile priority pollutants. Classes of compounds not detected in whole-water samples included carbamate insecticides, triazine and other nitrogen-containing herbicides, and purgeable organic compounds. Bottom-sediment samples contained many organochlorine compounds, including chlordane, DDT plus metabolites, dieldrin, endrin, heptachlor epoxide (a metabolite of heptachlor), and PCBs at some or all sites sampled. Twenty-four of 54 semivolatile compounds were detected in bottom- sediment samples at some or all sites sampled.

  14. Composition of semi-volatile organic compounds in the urban atmosphere of Singapore: influence of biomass burning

    NASA Astrophysics Data System (ADS)

    He, J.; Zielinska, B.; Balasubramanian, R.

    2010-12-01

    An intensive field study was conducted in the urban atmosphere of Singapore to investigate the composition of organic compounds in both gaseous and particulate phases during the period of August to early November 2006. 17 atmospheric samples were collected. These samples were subjected to accelerated solvent extraction with a mixture of dichloromethane and acetone and separated into functional group fractions for analyses by GC/MS. Over 180 organic compounds belonging to three major fractions (n-alkanes, polycyclic aromatic hydrocarbons - PAHs, and polar organic compounds - POCs) were identified and quantified. The characteristics and abundance of the n-alkanes, PAHs, mono and dicarboxylic acids, methoxylated phenols and other POCs were determined. The composition of these organic compounds fluctuated temporally with most of them being relatively higher in October than those in other months of the sampling period. 3-D backward air mass trajectory analyses together with the carbon preference index (CPI), molecular diagnostic ratios and molecular markers were used to investigate the origin of organic species measured in this study. Based on these diagnostic tools, the increased abundance of atmospheric organic species during October could be attributed to the occurrence of regional smoke haze episodes due to biomass burning in Indonesia. Among the POCs investigated, phthalic acid and cis-pinonic acid were abundant during October 2006. These two acids showed strong linear relationships with maximum daily ozone concentrations throughout the entire sampling period. This correlation with ozone suggested that the secondary aerosol constituents such as phthalic and cis-pinonic acids were probably formed through O3-induced photochemical transformation.

  15. Hygroscopicity of organic compounds as a function of carbon chain length, carboxyl, hydroperoxy, and carbonyl functional groups

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Petters, Sarah Suda; Pagonis, Demetrios; Claflin, Megan Suzanne

    The albedo and microphysical properties of clouds are controlled in part by the hygroscopicity of particles serving as cloud condensation nuclei (CCN). Hygroscopicity of complex organic mixtures in the atmosphere varies widely and remains challenging to predict. Here we present new measurements characterizing the CCN activity of pure compounds in which carbon chain length and the number of hydroperoxy, carboxyl, and carbonyl functional groups were systematically varied to establish the contributions of these groups to organic aerosol apparent hygroscopicity. Apparent hygroscopicity decreased with carbon chain length and increased with polar functional groups in the order carboxyl > hydroperoxy > carbonyl.more » Activation diameters at different supersaturations deviated from the -3/2 slope in log-log space predicted by Köhler theory, suggesting that water solubility limits CCN activity of particles composed of weakly functionalized organic compounds. Results are compared to a functional group contribution model that predicts CCN activity of organic compounds. The model performed well for most compounds but under-predicted the CCN activity of hydroperoxy groups. New best-fit hydroperoxy group/water interaction parameters were derived from the available CCN data. Lastly, these results may help improve estimates of the CCN activity of ambient organic aerosols from composition data.« less

  16. Hygroscopicity of organic compounds as a function of carbon chain length, carboxyl, hydroperoxy, and carbonyl functional groups

    DOE PAGES

    Petters, Sarah Suda; Pagonis, Demetrios; Claflin, Megan Suzanne; ...

    2017-06-16

    The albedo and microphysical properties of clouds are controlled in part by the hygroscopicity of particles serving as cloud condensation nuclei (CCN). Hygroscopicity of complex organic mixtures in the atmosphere varies widely and remains challenging to predict. Here we present new measurements characterizing the CCN activity of pure compounds in which carbon chain length and the number of hydroperoxy, carboxyl, and carbonyl functional groups were systematically varied to establish the contributions of these groups to organic aerosol apparent hygroscopicity. Apparent hygroscopicity decreased with carbon chain length and increased with polar functional groups in the order carboxyl > hydroperoxy > carbonyl.more » Activation diameters at different supersaturations deviated from the -3/2 slope in log-log space predicted by Köhler theory, suggesting that water solubility limits CCN activity of particles composed of weakly functionalized organic compounds. Results are compared to a functional group contribution model that predicts CCN activity of organic compounds. The model performed well for most compounds but under-predicted the CCN activity of hydroperoxy groups. New best-fit hydroperoxy group/water interaction parameters were derived from the available CCN data. Lastly, these results may help improve estimates of the CCN activity of ambient organic aerosols from composition data.« less

  17. Case study: Comparison of biological active compounds in milk from organic and conventional dairy herds

    USDA-ARS?s Scientific Manuscript database

    Conflicting reports of the quantities of biologically active compounds present in milk from organic grass-fed and conventional herds show that more research is required, especially as these compounds are linked to human health benefits and can improve the health value consumers place on dairy produc...

  18. Molecular Isotopic Characterization of the ALH 85013.50 Meteorite: Defining the Extraterrestrial Organic Compounds

    NASA Technical Reports Server (NTRS)

    Fuller, M.; Huang, Y.

    2003-01-01

    The Antarctic Meteorite Program has returned over 16,000 meteorites from the ice sheets of the Antarctic. This more than doubles the number of preexisting meteorite collection and adds important and rare specimens to the assemblage. The CM carbonaceous chondrites are of particular interest because of their high organic component. The Antarctic carbonaceous chondrites provide a large, previously uninvestigated suite of meteorites. Of the 161 CM chondrites listed in the Catalogue of Meteorites 138 of them have been recovered from the Antarctic ice sheets,. However, these meteorites have typically been exposed to Earth s conditions for long periods of time. The extent of terrestrial organic contamination and weathering that has taken place on these carbonaceous chondrites is unknown. In the past, stable isotope analysis was used to identify bulk organics that were extraterrestrial in origin. Although useful, this method could not exclude the possibility of terrestrial contamination contributing to the isotopic measurement. Compound specific isotope analysis of organic meteorite material has provided the opportunity to discern the terrestrial contamination from extraterrestrial organic compounds on the molecular level.

  19. Indoor Residence Times of Semivolatile Organic Compounds: Model Estimation and Field Evaluation

    EPA Science Inventory

    Indoor residence times of semivolatile organic compounds (SVOCs) are a major and mostly unavailable input for residential exposure assessment. We calculated residence times for a suite of SVOCs using a fugacity model applied to residential environments. Residence times depend on...

  20. MICROWAVE-ASSISTED EXTRACTION OF ORGANIC COMPOUNDS FROM STANDARD REFERENCE SOILS AND SEDIMENTS

    EPA Science Inventory

    As part of an ongoing evaluation of new sample preparation techniques by the U.S. Environmental Protection Agency (EPA), especially those that minimize waste solvents, microwave-assisted extraction (MAE) of organic compounds from solid materials (or "matrices") was evaluated. Six...

  1. Spatial analysis of volatile organic compounds in South Philadelphia using passive samplers

    EPA Science Inventory

    Select volatile organic compounds (VOCs) were measured in the vicinity of a petroleum refinery and related operations in South Philadelphia, Pennsylvania, USA, using passive air sampling and laboratory analysis methods. Two-week, time-integrated samplers were deployed at 17 sites...

  2. PILOT-SCALE EVALUATION OF AN INCINERABILITY RANKING SYSTEM FOR HAZARDOUS ORGANIC COMPOUNDS

    EPA Science Inventory

    The subject study was conducted to evaluate an incinerability ranking system developed by teh University of Dayton Research Institute under contract to the EPA Risk Reduction Engineering Laboratory. Fixtures of organic compounds were prepared and combined with a clay-based sorben...

  3. OPTIMIZATION OF MULTICOMPONENT PERVAPORATION FOR REMOVAL OF VOLATILE ORGANIC COMPOUNDS FROM WATER

    EPA Science Inventory

    Optimal operation of a hollow fiber membrane module for pervaporative removal of multicomponent volatile organic compounds (VOCs) from wastewater was studied. A shell-and-tube heat-exchange type of hollow fiber module was considered for treatment of a wastewater containing toluen...

  4. Effects of polar and nonpolar groups on the solubility of organic compounds in soil organic matter

    USGS Publications Warehouse

    Chiou, C.T.; Kile, D.E.

    1994-01-01

    Vapor sorption capacities on a high-organic-content peat, a model for soil organic matter (SOM), were determined at room temperature for the following liquids: n-hexane, 1,4-dioxane, nitroethane, acetone, acetonitrile, 1-propanol, ethanol, and methanol. The linear organic vapor sorption is in keeping with the dominance of vapor partition in peat SOM. These data and similar results of carbon tetrachloride (CT), trichloroethylene (TCE), benzene, ethylene glycol monoethyl ether (EGME), and water on the same peat from earlier studies are used to evaluate the effect of polarity on the vapor partition in SOM. The extrapolated liquid solubility from the vapor isotherm increases sharply from 3-6 wt % for low-polarity liquids (hexane, CT, and benzene) to 62 wt % for polar methanol and correlates positively with the liquid's component solubility parameters for polar interaction (??P) and hydrogen bonding (??h). The same polarity effect may be expected to influence the relative solubilities of a variety of contaminants in SOM and, therefore, the relative deviations between the SOM-water partition coefficients (Kom) and corresponding octanol-water partition coefficients (Kow) for different classes of compounds. The large solubility disparity in SOM between polar and nonpolar solutes suggests that the accurate prediction of Kom from Kow or Sw (solute water solubility) would be limited to compounds of similar polarity.

  5. Biofiltration for control of volatile organic compounds (VOCS)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bishop, D.F.; Govind, R.

    1995-10-01

    Air biofiltration is a promising technology for control of air emissions of biodegradable volatile organic compounds (VOCs). In conjunction with vacuum extraction of soils or air stripping of ground water, it can be used to mineralize VOCs removed from contaminated soil or groundwater. The literature describes three major biological systems for treating contaminated air bioscrubbers, biotrickling filters and biofilters. Filter media can be classified as: bioactive fine or irregular particulates, such as soil, peat, compost or mixtures of these materials; pelletized, which are randomly packed in a bed; and structured, such as monoliths with defined or variable passage size andmore » geometry. The media can be made of sorbing and non-absorbing materials. Non-bioactive pelletized and structured media require recycled solutions of nutrients and buffer for efficient microbial activity and are thus called biotrickling filters. Extensive work has been conducted to improve biofiltration by EPA`s Risk Reduction Engineering Laboratory and the University of Cincinnati in biofilters using pelletized and structured media and improved operational approaches. Representative VOCs in these studies included compounds with a range of aqueous solubilities and octanol-water partition coefficients. The compounds include iso-pentane, toluene, methylene chloride, trichloroethylene (TCE), ethyl benzene, chlorobenzene and perchloroethylene (PCE) and alpha ({alpha}-) pinene. Comparative studies were conducted with peat/compost biofilters using isopentane and {alpha}-pinene. Control studies were also conducted to investigate adsorption/desorption of contaminants on various media using mercuric chloride solution to insure the absence of bioactivity.« less

  6. Evaluating nephrotoxicity of high-molecular-weight organic compounds in drinking water from lignite aquifers

    USGS Publications Warehouse

    Bunnell, J.E.; Tatu, C.A.; Lerch, H.E.; Orem, W.H.; Pavlovic, N.

    2007-01-01

    High-molecular-weight organic compounds such as humic acids and/or fulvic acids that are naturally mobilized from lignite beds into untreated drinking-water supplies were suggested as one possible cause of Balkan endemic nephropathy (BEN) and cancer of the renal pelvis. A lab investigation was undertaken in order to assess the nephrotoxic potential of such organic compounds using an in vitro tissue culture model. Because of the infeasibility of exposing kidney tissue to low concentrations of organics for years in the lab, tangential flow ultrafiltration was employed to hyperconcentrate samples suitable for discerning effects in the short time frames necessitated by tissue culture systems. Effects on HK-2 kidney cells were measured using two different cell proliferation assays (MTT and alamarBlue). Results demonstrated that exposure of kidney tissue to high-molecular-weight organics produced excess cell death or proliferation depending on concentration and duration of exposure. Copyright ?? Taylor & Francis Group, LLC.

  7. Computational assessment of organic photovoltaic candidate compounds

    NASA Astrophysics Data System (ADS)

    Borunda, Mario; Dai, Shuo; Olivares-Amaya, Roberto; Amador-Bedolla, Carlos; Aspuru-Guzik, Alan

    2015-03-01

    Organic photovoltaic (OPV) cells are emerging as a possible renewable alternative to petroleum based resources and are needed to meet our growing demand for energy. Although not as efficient as silicon based cells, OPV cells have as an advantage that their manufacturing cost is potentially lower. The Harvard Clean Energy Project, using a cheminformatic approach of pattern recognition and machine learning strategies, has ranked a molecular library of more than 2.6 million candidate compounds based on their performance as possible OPV materials. Here, we present a ranking of the top 1000 molecules for use as photovoltaic materials based on their optical absorption properties obtained via time-dependent density functional theory. This computational search has revealed the molecular motifs shared by the set of most promising molecules.

  8. Molecular composition of soil organic matter with land-use change along a bi-continental mean annual temperature gradient.

    PubMed

    Pisani, Oliva; Haddix, Michelle L; Conant, Richard T; Paul, Eldor A; Simpson, Myrna J

    2016-12-15

    Soil organic matter (SOM) is critical for maintaining soil fertility and long-term agricultural sustainability. The molecular composition of SOM is likely altered due to global climate and land-use change; but rarely are these two aspects studied in tandem. Here we used molecular-level techniques to examine SOM composition along a bi-continental (from North to South America) mean annual temperature (MAT) gradient from seven native grassland/forest and cultivated/pasture sites. Biomarker methods included solvent extraction, base hydrolysis and cupric (II) oxide oxidation for the analysis of free lipids of plant and microbial origin, ester-bound lipids from cutin and suberin, and lignin-derived phenols, respectively. Solid-state 13 C nuclear magnetic resonance (NMR) was used to examine the overall composition of SOM. Soil cultivation was found to increase the amount of microbial-derived compounds at warmer temperatures (up to 17% increase). The cultivated soils were characterized by much lower contributions of plant-derived SOM components compared to the native soils (up to 64% lower at the coldest site). In addition, cultivation caused an increase in lignin and cutin degradation (up to 68 and 15% increase, respectively), and an increase in the amount of suberin-derived inputs (up to 54% increase). Clear differences in the molecular composition of SOM due to soil cultivation were observed in soils of varying mineral composition and were attributed to disturbance, different vegetation inputs, soil aggregate destruction and MAT. A high organic allophanic tropical soil was characterized by its protection of carbohydrates and nitrogen-containing compounds. The conversion of native to cultivated land shows significant shifts in the degradation stage of SOM. In particular, cutin-derived compounds which are believed to be part of the stable SOM pool may undergo enhanced degradation with long-term cultivation and disruption of soil aggregates. On a per year basis, the total

  9. Electrocatalytic hydrogenation and hydrodeoxygenation of oxygenated and unsaturated organic compounds

    DOEpatents

    Jackson, James E.; Lam, Chun Ho; Saffron, Christopher M.; Miller, Dennis J.

    2018-04-24

    A process and related electrode composition are disclosed for the electrocatalytic hydrogenation and/or hydrodeoxygenation of organic substrates such as biomass-derived bio-oil components by the production of hydrogen atoms on a catalyst surface followed by the reaction of the hydrogen atoms with the organic reactants. Biomass fast pyrolysis-derived bio-oil is a liquid mixture containing hundreds of organic compounds with chemical functionalities that are corrosive to container materials and are prone to polymerization. A high surface area skeletal metal catalyst material such as Raney Nickel can be used as the cathode. Electrocatalytic hydrogenation and/or hydrodeoxygenation convert the organic substrates under mild conditions to reduce coke formation and catalyst deactivation. The process converts oxygen-containing functionalities and unsaturated bonds into chemically reduced forms with an increased hydrogen content. The process is operated at mild conditions, which enables it to be a good means for stabilizing bio-oil to a form that can be stored and transported using metal containers and pipes.

  10. Fulvic acid like organic compounds control nucleation of marine calcite under suboxic conditions

    NASA Astrophysics Data System (ADS)

    Neuweiler, Fritz; D'Orazio, Valeria; Immenhauser, Adrian; Geipel, Gerhard; Heise, Karl-Heinz; Cocozza, Claudio; Miano, Teodoro M.

    2003-08-01

    Intracrystalline organic compounds, enclosed within in situ precipitated marine microcrystalline calcite (automicrite), might represent either an inclusion or the catalyst of such precipitation. We use evidence from a Lower Cretaceous deep-water carbonate mound to show (1) the original source, (2) the degree of condensation, (3) the redox conditions involved, and (4) the catalytic role of natural organic matter for the precipitation of automicrite. Fluorescence spectrometry of the intracrystalline organic fraction extracted from these carbonates identifies a marine fulvic acid like organic compound with a low degree of polycondensation. This finding points to a temporal correlation of the initial stage of geopolymer formation with the precipitation of automicrite. Furthermore, the rare earth element (REE) distribution patterns in the mineral show a consistent positive Ce anomaly, suggesting an episode of reductive dissolution of iron-manganese oxyhydroxides during automicrite formation. In general, a relative enrichment of middle-weight REEs is observed, resulting in a convex distribution pattern typical for, e.g., phosphate concretions or humic acid material. By merging the results of spectrometry and REE geochemistry we thus conclude that the marine calcite precipitation was catalyzed by marine fulvic acid like compounds during the early stages of humification under suboxic conditions. This indicates that humification, driven by the presence of a benthic biomass, is more important for calcite authigenesis than any site-specific microbial metabolism. The Neoproterozoic rise of carbonate mounds supports this hypothesis; there is molecular evidence for early metazoan divergence then, but not for a major evolutionary episode of microorganisms.

  11. Experimental design for extraction and quantification of phenolic compounds and organic acids in white "Vinho Verde" grapes.

    PubMed

    Dopico-García, M S; Valentão, P; Guerra, L; Andrade, P B; Seabra, R M

    2007-01-30

    An experimental design was applied for the optimization of extraction and clean-up processes of phenolic compounds and organic acids from white "Vinho Verde" grapes. The developed analytical method consisted in two steps: first a solid-liquid extraction of both phenolic compounds and organic acids and then a clean-up step using solid-phase extraction (SPE). Afterwards, phenolic compounds and organic acids were determined by high-performance liquid chromatography (HPLC) coupled to a diode array detector (DAD) and HPLC-UV, respectively. Plackett-Burman design was carried out to select the significant experimental parameters affecting both the extraction and the clean-up steps. The identified and quantified phenolic compounds were: quercetin-3-O-glucoside, quercetin-3-O-rutinoside, kaempferol-3-O-rutinoside, isorhamnetin-3-O-glucoside, quercetin, kaempferol and epicatechin. The determined organic acids were oxalic, citric, tartaric, malic, shikimic and fumaric acids. The obtained results showed that the most important variables were the temperature (40 degrees C) and the solvent (acid water at pH 2 with 5% methanol) for the extraction step and the type of sorbent (C18 non end-capped) for the clean-up step.

  12. RECOVERY OF SEMI-VOLATILE ORGANIC COMPOUNDS DURING SAMPLE PREPARATION: IMPLICATIONS FOR CHARACTERIZATION OF AIRBORNE PARTICULATE MATTER

    EPA Science Inventory

    Semi-volatile compounds present special analytical challenges not met by conventional methods for analysis of ambient particulate matter (PM). Accurate quantification of PM-associated organic compounds requires validation of the laboratory procedures for recovery over a wide v...

  13. The Measurement of Atmospheric Concentrations and Deposition of Semi-Volatile Organic Compounds.

    ERIC Educational Resources Information Center

    Lee, David S.; Nicholson, Ken W.

    1994-01-01

    Provides a physical description of semivolatile organic compounds (SVOCs), both in terms of their characteristic nature in the atmosphere and the processes which control their deposition. Contains a summary of the requirements for a full assessment of atmospheric SVOCs and their deposition. (LZ)

  14. Modeling emissions of volatile organic compounds from silage storages and feed lanes

    USDA-ARS?s Scientific Manuscript database

    An initial volatile organic compound (VOC) emission model for silage sources, developed using experimental data from previous studies, was incorporated into the Integrated Farm System Model (IFSM), a whole-farm simulation model used to assess the performance, environmental impacts, and economics of ...

  15. NATURAL VOLATILE ORGANIC COMPOUND EMISSION RATE ESTIMATES FOR U.S. WOODLAND LANDSCAPES

    EPA Science Inventory

    Volatile organic compound (VOC) emission rate factors are estimated for 49 tree genera based on a review of foliar emission rate measurements. oliar VOC emissions are grouped into three categories: isoprene, monoterpenes and other VOC'S. ypical emission rates at a leaf temperatur...

  16. IDENTIFICATION OF POLAR VOLATILE ORGANIC COMPOUNDS IN CONSUMER PRODUCTS AND COMMON MICROENVIRONMENTS

    EPA Science Inventory

    Polar volatile organic compounds were identified in the headspace of 31 fragrance products such as perfumes, colognes and soaps. About 150 different chemicals were identified in a semiquantitative fashion, using two methods to analyze the headspace: direct injection into a gas ch...

  17. Nitrate radicals and biogenic volatile organic compounds: oxidation, mechanisms, and organic aerosol

    NASA Astrophysics Data System (ADS)

    Ng, Nga Lee; Brown, Steven S.; Archibald, Alexander T.; Atlas, Elliot; Cohen, Ronald C.; Crowley, John N.; Day, Douglas A.; Donahue, Neil M.; Fry, Juliane L.; Fuchs, Hendrik; Griffin, Robert J.; Guzman, Marcelo I.; Herrmann, Hartmut; Hodzic, Alma; Iinuma, Yoshiteru; Jimenez, José L.; Kiendler-Scharr, Astrid; Lee, Ben H.; Luecken, Deborah J.; Mao, Jingqiu; McLaren, Robert; Mutzel, Anke; Osthoff, Hans D.; Ouyang, Bin; Picquet-Varrault, Benedicte; Platt, Ulrich; Pye, Havala O. T.; Rudich, Yinon; Schwantes, Rebecca H.; Shiraiwa, Manabu; Stutz, Jochen; Thornton, Joel A.; Tilgner, Andreas; Williams, Brent J.; Zaveri, Rahul A.

    2017-02-01

    Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO3) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 decades, during which time a large body of research has emerged from laboratory, field, and modeling studies. NO3-BVOC reactions influence air quality, climate and visibility through regional and global budgets for reactive nitrogen (particularly organic nitrates), ozone, and organic aerosol. Despite its long history of research and the significance of this topic in atmospheric chemistry, a number of important uncertainties remain. These include an incomplete understanding of the rates, mechanisms, and organic aerosol yields for NO3-BVOC reactions, lack of constraints on the role of heterogeneous oxidative processes associated with the NO3 radical, the difficulty of characterizing the spatial distributions of BVOC and NO3 within the poorly mixed nocturnal atmosphere, and the challenge of constructing appropriate boundary layer schemes and non-photochemical mechanisms for use in state-of-the-art chemical transport and chemistry-climate models. This review is the result of a workshop of the same title held at the Georgia Institute of Technology in June 2015. The first half of the review summarizes the current literature on NO3-BVOC chemistry, with a particular focus on recent advances in instrumentation and models, and in organic nitrate and secondary organic aerosol (SOA) formation chemistry. Building on this current understanding, the second half of the review outlines impacts of NO3-BVOC chemistry on air quality and climate, and suggests critical research needs to better constrain this interaction to improve the predictive capabilities of atmospheric models.

  18. Nitrate radicals and biogenic volatile organic compounds: oxidation, mechanisms, and organic aerosol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ng, Nga Lee; Brown, Steven S.; Archibald, Alexander T.

    Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO 3) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 decades, during which time a large body of research has emerged from laboratory, field, and modeling studies. NO 3-BVOC reactions influence air quality, climate and visibility through regional and global budgets for reactive nitrogen (particularly organic nitrates), ozone, and organic aerosol. Despite its long history of research and the significance of this topic in atmospheric chemistry, a number of importantmore » uncertainties remain. These include an incomplete understanding of the rates, mechanisms, and organic aerosol yields for NO 3-BVOC reactions, lack of constraints on the role of heterogeneous oxidative processes associated with the NO 3 radical, the difficulty of characterizing the spatial distributions of BVOC and NO 3 within the poorly mixed nocturnal atmosphere, and the challenge of constructing appropriate boundary layer schemes and non-photochemical mechanisms for use in state-of-the-art chemical transport and chemistry–climate models. This review is the result of a workshop of the same title held at the Georgia Institute of Technology in June 2015. The first half of the review summarizes the current literature on NO 3-BVOC chemistry, with a particular focus on recent advances in instrumentation and models, and in organic nitrate and secondary organic aerosol (SOA) formation chemistry. Building on this current understanding, the second half of the review outlines impacts of NO 3-BVOC chemistry on air quality and climate, and suggests critical research needs to better constrain this interaction to improve the predictive capabilities of atmospheric models.« less

  19. The identification of polar organic compounds found in consumer products and their toxicological properties.

    PubMed

    Cooper, S D; Raymer, J H; Pellizzari, E D; Thomas, K W

    1995-01-01

    Exposure to volatile organic compounds (VOCs) in the indoor environment has received substantial research attention in the past several years, with the goal of better understanding the impact of such exposures on human health and well-being. Many VOCs can arise from consumer products used within the indoor environment. The VOCs emitted from five representative consumer products were collected onto Tenax-GC and subjected to thermal desorption and analysis by gas chromatography, in combination with low-resolution mass spectrometry (MS), high-resolution MS, and matrix-isolation Fourier transform infrared spectroscopy for structural characterization. An emphasis was placed on the polar organic compounds often used to provide fragrance in these products. The structures of a number of these compounds were confirmed, and an electronic literature search was carried out on them to determine any known toxic properties. The search revealed that many of the VOCs possess toxic properties when studied at acute, relatively high-level exposures. In addition, toxic effects were reported for a few of the chemicals, such as benzaldehyde, alpha-terpineol, benzyl acetate, and ethanol, at relatively low dose levels of 9-14 mg/kg. In general, the data were unclear as to the effect of chronic, low-level exposures. The widespread use of such chemicals suggests that the health effects of chronic exposures need to be determined. Validated analytical methods for the quantitative characterization of polar organic compounds at low concentrations will be required to make such work possible.

  20. New global fire emission estimates and evaluation of volatile organic compounds

    Treesearch

    C. Wiedinmyer; L. K. Emmons; S. K. Akagi; R. J. Yokelson; J. J. Orlando; J. A. Al-Saadi; A. J. Soja

    2010-01-01

    A daily, high-resolution, global fire emissions model has been built to estimate emissions from open burning for air quality modeling applications: The Fire INventory from NCAR (FINN version 1). The model framework uses daily fire detections from the MODIS instruments and updated emission factors, specifically for speciated non-methane organic compounds (NMOC). Global...

  1. Acute Toxicity of the Antifouling Compound Butenolide in Non-Target Organisms

    PubMed Central

    Chandramouli, Kondethimmanahalli H.; Xu, Ying; Pan, Ke; Wang, Wen-Xiong; Qian, Pei-Yuan

    2011-01-01

    Butenolide [5-octylfuran-2(5H)-one] is a recently discovered and very promising anti-marine-fouling compound. In this study, the acute toxicity of butenolide was assessed in several non-target organisms, including micro algae, crustaceans, and fish. Results were compared with previously reported results on the effective concentrations used on fouling (target) organisms. According to OECD's guideline, the predicted no effect concentration (PNEC) was 0.168 µg l−1, which was among one of the highest in representative new biocides. Mechanistically, the phenotype of butenolide-treated Danio rerio (zebrafish) embryos was similar to the phenotype of the pro-caspase-3 over-expression mutant with pericardial edema, small eyes, small brains, and increased numbers of apoptotic cells in the bodies of zebrafish embryos. Butenolide also induced apoptosis in HeLa cells, with the activation of c-Jun N-terminal kinases (JNK), Bcl-2 family proteins, and caspases and proteasomes/lysosomes involved in this process. This is the first detailed toxicity and toxicology study on this antifouling compound. PMID:21897857

  2. Photoelectrochemical Performance of TiO2/Ti Electrode for Organic Compounds

    NASA Astrophysics Data System (ADS)

    Maulidiyah, M.; Wijawan, I. B. P.; Wibowo, D.; Aladin, A.; Hamzah, B.; Nurdin, M.

    2018-05-01

    Photoelectrochemical performance of TiO2/Ti electrode was investigated by using organic compounds. The TiO2/Ti electrode was prepared by anodic oxidation at a potential bias of 25 V for 4 h then calcined for 450 °C to obtain the anatase polymorph. Subsequently, it was characterized by X-Ray Diffraction (XRD) and Scanning Electron Microscope-Energy Dispersive X-ray (SEM-EDX). The XRD pattern showed that TiO2 has anatase phase as confirmed by 2θ peaks at 37.93° 63.00°, and 83.00°. Using SEM-EDX data the TiO2 layer was formed on Ti plate with the composition of Ti (4.5 keV) and O (0.5 keV) elements. Furthermore, the photoelectrochemical sensing on the three organic compounds (ascorbic acid, glucose, and titan yellow) with the electrolyte addition showed that the linearity of TiO2/Ti electrode were 0.937, 0.968, and 0.938, meanwhile without the electrolyte were 0.998, 0.989, and 0.923, respectively.

  3. Fate of pharmaceutical and trace organic compounds in three septic system plumes, Ontario, Canada.

    PubMed

    Carrara, Cherilyn; Ptacek, Carol J; Robertson, William D; Blowes, David W; Moncur, Michael C; Sverko, Ed; Backus, Sean

    2008-04-15

    Three high volume septic systems in Ontario, Canada, were examined to assess the potential for onsite wastewatertreatment systems to release pharmaceutical compounds to the environment and to evaluate the mobility of these compounds in receiving aquifers. Wastewater samples were collected from the septic tanks, and groundwater samples were collected below and down gradient of the infiltration beds and analyzed for a suite of commonly used pharmaceutical and trace organic compounds. The septic tank samples contained elevated concentrations of several pharmaceutical compounds. Ten of the 12 compounds analyzed were detected in groundwater at one or more sites at concentrations in the low ng L(-1) to low microg L(-1) range. Large differences among the sites were observed in both the number of detections and the concentrations of the pharmaceutical compounds. Of the compounds analyzed, ibuprofen, gemfibrozil, and naproxen were observed to be transported atthe highest concentrations and greatest distances from the infiltration source areas, particularly in anoxic zones of the plumes.

  4. Prediction of solvation enthalpy of gaseous organic compounds in propanol

    NASA Astrophysics Data System (ADS)

    Golmohammadi, Hassan; Dashtbozorgi, Zahra

    2016-09-01

    The purpose of this paper is to present a novel way for developing quantitative structure-property relationship (QSPR) models to predict the gas-to-propanol solvation enthalpy (Δ H solv) of 95 organic compounds. Different kinds of descriptors were calculated for each compound using the Dragon software package. The variable selection technique of replacement method (RM) was employed to select the optimal subset of solute descriptors. Our investigation reveals that the dependence of physical chemistry properties of solution on solvation enthalpy is nonlinear and that the RM method is unable to model the solvation enthalpy accurately. The results established that the calculated Δ H solv values by SVM were in good agreement with the experimental ones, and the performances of the SVM models were superior to those obtained by RM model.

  5. Long-term stability measurements of low concentration Volatile Organic Compound gas mixtures

    NASA Astrophysics Data System (ADS)

    Allen, Nick; Amico di Meane, Elena; Brewer, Paul; Ferracci, Valerio; Corbel, Marivon; Worton, David

    2017-04-01

    VOCs (Volatile Organic Compounds) are a class of compounds with significant influence on the atmosphere due to their large anthropogenic and biogenic emission sources. VOC emissions have a significant impact on the atmospheric hydroxyl budget and nitrogen reservoir species, while also contributing indirectly to the production of tropospheric ozone and secondary organic aerosol. However, the global budget of many of these species are poorly constrained. Moreover, the World Meteorological Organization's (WMO) Global Atmosphere Watch (GAW) have set challenging data quality objectives for atmospheric monitoring programmes for these classes of traceable VOCs, despite the lack of available stable gas standards. The Key-VOCs Joint Research Project is an ongoing three-year collaboration with the aim of improving the measurement infrastructure of important atmospheric VOCs by providing traceable and comparable reference gas standards and by validating new measurement systems in support of the air monitoring networks. It focuses on VOC compounds that are regulated by European legislation, that are relevant for indoor air monitoring and for air quality and climate monitoring programmes like the VOC programme established by the WMO GAW and the European Monitoring and Evaluation Programme (EMEP). These VOCs include formaldehyde, oxy[genated]-VOCs (acetone, ethanol and methanol) and terpenes (a-pinene, 1,8-cineole, δ-3-carene and R-limonene). Here we present the results of a novel long term stability study for low concentration formaldehyde, oxy-VOC and terpenes gas mixtures produced by the Key-VOCs consortium with discussion regarding the implementation of improved preparation techniques and the use of novel cylinder passivation chemistries to guarantee mixture stability.

  6. Volatile organic compounds in the marine troposphere and surface oceans: methods, measurements and biogeochemical implications

    NASA Astrophysics Data System (ADS)

    Hudson, Edward

    2010-09-01

    Volatile organic compounds (VOCs), among them non-methane hydrocarbons (NMHCs) and low molecular weight carbonyl compounds (aldehydes and ketones), affect the oxidative capacity of the atmosphere and thus pollutant lifetimes and global climate. VOCs in the surface oceans may be transported into, or derived from, the atmosphere. This thesis describes the development and optimization of chromatographic and preconcentration methods to determine volatile organic compounds (VOCs) in surface seawater and marine air, and their use to explore VOC distribution and fluxes at the seaair interface. It includes the first measurements of many carbonyl compounds in temperate and subarctic marine waters and the first estimates of fluxes of several aldehydes from the ocean surface into the marine atmosphere. Sea surface air, size-fractionated marine aerosols, and surface ocean water dissolved organic matter were simultaneously sampled in the Nordic seas. Nineteen C2-C7 NMHCs were quantified in the air samples. Site-to-site variability in NMHC concentrations was high, suggesting variable, local sources. The aerosols consisted mainly of inorganic marine material, but a culturable bacterium identified as Micrococcus luteus was also isolated from the 9.9 -- 18 mum fraction, suggesting organic matter may be transferred from the surface oceans to the atmosphere by marine aerosols. Lastly, a number of VOCs, including acetone, were detected in the seawater samples using solid-phase microextraction (SPME), leading to the subsequent development of an SPME application for carbonyl compounds in seawater. A mobile, economical and solventless method for the detection and quantification of carbonyl compounds in seawater, a matrix of global importance, was developed. The compounds were derivatized using O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBHA)and then pre-concentrated by SPME for gas chromatography with mass spectrometric (GC/MS) or flame ionization (GC-FID) detection. The method was

  7. Isotopic disproportionation during hydrogen isotopic analysis of nitrogen-bearing organic compounds

    USGS Publications Warehouse

    Nair, Sreejesh; Geilmann, Heike; Coplen, Tyler B.; Qi, Haiping; Gehre, Matthias; Schimmelmann, Arndt; Brand, Willi A.

    2015-01-01

    Rationale High-precision hydrogen isotope ratio analysis of nitrogen-bearing organic materials using high-temperature conversion (HTC) techniques has proven troublesome in the past. Formation of reaction products other than molecular hydrogen (H2) has been suspected as a possible cause of incomplete H2 yield and hydrogen isotopic fractionation. Methods The classical HTC reactor setup and a modified version including elemental chromium, both operated at temperatures in excess of 1400 °C, have been compared using a selection of nitrogen-bearing organic compounds, including caffeine. A focus of the experiments was to avoid or suppress hydrogen cyanide (HCN) formation and to reach quantitative H2 yields. The technique also was optimized to provide acceptable sample throughput. Results The classical HTC reaction of a number of selected compounds exhibited H2 yields from 60 to 90 %. Yields close to 100 % were measured for the experiments with the chromium-enhanced reactor. The δ2H values also were substantially different between the two types of experiments. For the majority of the compounds studied, a highly significant relationship was observed between the amount of missing H2and the number of nitrogen atoms in the molecules, suggesting the pyrolytic formation of HCN as a byproduct. A similar linear relationship was found between the amount of missing H2 and the observed hydrogen isotopic result, reflecting isotopic fractionation. Conclusions The classical HTC technique to produce H2 from organic materials using high temperatures in the presence of glassy carbon is not suitable for nitrogen-bearing compounds. Adding chromium to the reaction zone improves the yield to 100 % in most cases. The initial formation of HCN is accompanied by a strong hydrogen isotope effect, with the observed hydrogen isotope results on H2 being substantially shifted to more negative δ2H values. The reaction can be understood as an initial disproportionation leading to H2 and HCN

  8. Volatilization of organic compounds from streams

    USGS Publications Warehouse

    Rathburn, R.E.; Tai, D.Y.

    1982-01-01

    Mass-transfer coefficients for the volatilization of ethylene and propane were correlated with the hydraulic and geometric properties of seven streams, and predictive equations were developed. The equations were evaluated using a normalized root-mean-square error as the criterion of comparison. The two best equations were a two-variable equation containing the energy dissipated per unit mass per unit time and the average depth of flow and a three-variable equation containing the average velocity, the average depth of flow, and the slope of the stream. Procedures for adjusting the ethylene and propane coefficients for other organic compounds were evaluated. These procedures are based on molecular diffusivity, molecular diameter, or molecular weight. Because of limited data, none of these procedures have been extensively verified. Therefore, until additional data become available, it is suggested that the mass-transfer coefficient be assumed to be inversely proportional to the square root of the molecular weight.

  9. COLLECTION OF A SINGLE ALVEOLAR EXHALED BREATH FOR VOLATILE ORGANIC COMPOUNDS ANALYSIS

    EPA Science Inventory

    Measurement of specific organic compounds in exhaled breath has been used as an indicator of recent exposure to pollutants or as an indicator of the health of an individual. Typical application involves the collection of multiple breaths onto a sorbent cartridge or into an evacua...

  10. Study of Biogenic Volatile Organic Compounds at the French Guiana Tropical Forest

    NASA Astrophysics Data System (ADS)

    Corain Lopes, Paula Regina; Guenther, Alex; Turnipseed, Andrew; Bonal, Damien; Serça, Dominique; Burban, Benôit; Siebicke, Lukas; Emmons, Louisa; Bustillos, José Oscar W. V.

    2013-04-01

    Biogenic volatile organic compound (BVOCs) emissions play an important role in regional air quality and global atmospheric chemistry. In addition, these natural VOC emissions serve important biological functions including attracting and repelling pollinators and herbivores. Some biological organisms use ambient air as a communication medium and the oxidation of these compounds brings about the concentration gradients sensed by insects and other organisms. Isoprene is the predominant BVOC emitted by vegetation and tropical forests are the dominant global source. This compound is very reactive in the atmosphere and contributes to the reactions that control tropospheric oxidant concentrations and thus the concentrations and lifetimes of longer-lived species. This paper presents a study on the seasonal variations in isoprene and some other significant BVOCs such as α-pinene, β-pinene, limonene, e-β ocimene and longifolene, measured at the Guyaflux Tower located in a wet tropical forest in Paracou French Guiana (5o16´54´´N, 52o54´44´´W), during the year of 2011, using the Relaxed Eddy Accumulation technique at approximately 20 meters high above the canopy. The results show a lower concentration of isoprene during the month of February and March which correspond to the wet season with an average of 0,545 μg/m3 and 0,341 μg/m3, respectively followed by a slight increase in middle April (still wet season) and a higher concentration later in mid-June. The same behavior was observed for α-pinene with higher concentrations for the same periods as isoprene however with a smaller increase. All the other compounds had concentrations below 1 μg/m3during the whole year. The monoterpene, e-β ocimene, was observed and is known as a stress compound but the vegetation at the site did not face any known severe stress condition such as excessive drought or flooding. Concerning the fluxes, the results showed that just a small amount of BVOCs were deposited by wet or dry

  11. Malodorous volatile organic sulfur compounds: Sources, sinks and significance in inland waters.

    PubMed

    Watson, Susan B; Jüttner, Friedrich

    2017-03-01

    Volatile Organic Sulfur Compounds (VOSCs) are instrumental in global S-cycling and greenhouse gas production. VOSCs occur across a diversity of inland waters, and with widespread eutrophication and climate change, are increasingly linked with malodours in organic-rich waterbodies and drinking-water supplies. Compared with marine systems, the role of VOSCs in biogeochemical processes is far less well characterized for inland waters, and often involves different physicochemical and biological processes. This review provides an updated synthesis of VOSCs in inland waters, focusing on compounds known to cause malodours. We examine the major limnological and biochemical processes involved in the formation and degradation of alkylthiols, dialkylsulfides, dialkylpolysulfides, and other organosulfur compounds under different oxygen, salinity and mixing regimes, and key phototropic and heterotrophic microbial producers and degraders (bacteria, cyanobacteria, and algae) in these environs. The data show VOSC levels which vary significantly, sometimes far exceeding human odor thresholds, generated by a diversity of biota, biochemical pathways, enzymes and precursors. We also draw attention to major issues in sampling and analytical artifacts which bias and preclude comparisons among studies, and highlight significant knowledge gaps that need addressing with careful, appropriate methods to provide a more robust understanding of the potential effects of continued global development.

  12. Evaluating the mutagenic potential of aerosol organic compounds using informatics-based screening

    NASA Astrophysics Data System (ADS)

    Decesari, Stefano; Kovarich, Simona; Pavan, Manuela; Bassan, Arianna; Ciacci, Andrea; Topping, David

    2018-02-01

    Whilst general policy objectives to reduce airborne particulate matter (PM) health effects are to reduce exposure to PM as a whole, emerging evidence suggests that more detailed metrics associating impacts with different aerosol components might be needed. Since it is impossible to conduct toxicological screening on all possible molecular species expected to occur in aerosol, in this study we perform a proof-of-concept evaluation on the information retrieved from in silico toxicological predictions, in which a subset (N = 104) of secondary organic aerosol (SOA) compounds were screened for their mutagenicity potential. An extensive database search showed that experimental data are available for 13 % of the compounds, while reliable predictions were obtained for 82 %. A multivariate statistical analysis of the compounds based on their physico-chemical, structural, and mechanistic properties showed that 80 % of the compounds predicted as mutagenic were grouped into six clusters, three of which (five-membered lactones from monoterpene oxidation, oxygenated multifunctional compounds from substituted benzene oxidation, and hydroperoxides from several precursors) represent new candidate groups of compounds for future toxicological screenings. These results demonstrate that coupling model-generated compositions to in silico toxicological screening might enable more comprehensive exploration of the mutagenic potential of specific SOA components.

  13. Sensitivity of Aerosol Mass and Microphysics to Treatments of Condensational Growth of Secondary Organic Compounds in a Regional Model

    NASA Astrophysics Data System (ADS)

    Topping, D. O.; Lowe, D.; McFiggans, G.; Zaveri, R. A.

    2016-12-01

    Gas to particle partitioning of atmospheric compounds occurs through disequilibrium mass transfer rather than through instantaneous equilibrium. However, it is common to treat only the inorganic compounds as partitioning dynamically whilst organic compounds, represented by the Volatility Basis Set (VBS), are partitioned instantaneously. In this study we implement a more realistic dynamic partitioning of organic compounds in a regional framework and assess impact on aerosol mass and microphysics. It is also common to assume condensed phase water is only associated with inorganic components. We thus also assess sensitivity to assuming all organics are hygroscopic according to their prescribed molecular weight.For this study we use WRF-Chem v3.4.1, focusing on anthropogenic dominated North-Western Europe. Gas-phase chemistry is represented using CBM-Z whilst aerosol dynamics are simulated using the 8-section MOSAIC scheme, including a 9-bin volatility basis set (VBS) treatment of organic aerosol. Results indicate that predicted mass loadings can vary significantly. Without gas phase ageing of higher volatility compounds, dynamic partitioning always results in lower mass loadings downwind of emission sources. The inclusion of condensed phase water in both partitioning models increases the predicted PM mass, resulting from a larger contribution from higher volatility organics, if present. If gas phase ageing of VBS compounds is allowed to occur in a dynamic model, this can often lead to higher predicted mass loadings, contrary to expected behaviour from a simple non-reactive gas phase box model. As descriptions of aerosol phase processes improve within regional models, the baseline descriptions of partitioning should retain the ability to treat dynamic partitioning of organic compounds. Using our simulations, we discuss whether derived sensitivities to aerosol processes in existing models may be inherently biased.This work was supported by the Nature Environment

  14. Microbial communities related to volatile organic compound emission in automobile air conditioning units.

    PubMed

    Diekmann, Nina; Burghartz, Melanie; Remus, Lars; Kaufholz, Anna-Lena; Nawrath, Thorben; Rohde, Manfred; Schulz, Stefan; Roselius, Louisa; Schaper, Jörg; Mamber, Oliver; Jahn, Dieter; Jahn, Martina

    2013-10-01

    During operation of mobile air conditioning (MAC) systems in automobiles, malodours can occur. We studied the microbial communities found on contaminated heat exchanger fins of 45 evaporators from car MAC systems which were operated in seven different regions of the world and identified corresponding volatile organic compounds. Collected biofilms were examined by scanning electron microscopy and fluorescent in situ hybridization. The detected bacteria were loosely attached to the metal surface. Further analyses of the bacteria using PCR-based single-strand conformation polymorphism and sequencing of isolated 16S rRNA gene fragments identified highly divergent microbial communities with multiple members of the Alphaproteobacteriales, Methylobacteria were the prevalent bacteria. In addition, Sphingomonadales, Burkholderiales, Bacillales, Alcanivorax spp. and Stenotrophomonas spp. were found among many others depending on the location the evaporators were operated. Interestingly, typical pathogenic bacteria related to air conditioning systems including Legionella spp. were not found. In order to determine the nature of the chemical compounds produced by the bacteria, the volatile organic compounds were examined by closed loop stripping analysis and identified by combined gas chromatography/mass spectrometry. Sulphur compounds, i.e. di-, tri- and multiple sulphides, acetylthiazole, aromatic compounds and diverse substituted pyrazines were detected. Mathematical clustering of the determined microbial community structures against their origin identified a European/American/Arabic cluster versus two mainly tropical Asian clusters. Interestingly, clustering of the determined volatiles against the origin of the corresponding MAC revealed a highly similar pattern. A close relationship of microbial community structure and resulting malodours to the climate and air quality at the location of MAC operation was concluded.

  15. Organic Compounds in Clackamas River Water Used for Public Supply near Portland, Oregon, 2003-05

    USGS Publications Warehouse

    Carpenter, Kurt D.; McGhee, Gordon

    2009-01-01

    Organic compounds studied in this U.S. Geological Survey (USGS) assessment generally are man-made, including pesticides, gasoline hydrocarbons, solvents, personal care and domestic-use products, disinfection by-products, and manufacturing additives. In all, 56 compounds were detected in samples collected approximately monthly during 2003-05 at the intake for the Clackamas River Water plant, one of four community water systems on the lower Clackamas River. The diversity of compounds detected suggests a variety of different sources and uses (including wastewater discharges, industrial, agricultural, domestic, and others) and different pathways to drinking-water supplies (point sources, precipitation, overland runoff, ground-water discharge, and formation during water treatment). A total of 20 organic compounds were commonly detected (in at least 20 percent of the samples) in source water and (or) finished water. Fifteen compounds were commonly detected in source water, and five of these compounds (benzene, m- and p-xylene, diuron, simazine, and chloroform) also were commonly detected in finished water. With the exception of gasoline hydrocarbons, disinfection by-products, chloromethane, and the herbicide diuron, concentrations in source and finished water were less than 0.1 microgram per liter and always less than human-health benchmarks, which are available for about 60 percent of the compounds detected. On the basis of this screening-level assessment, adverse effects to human health are assumed to be negligible (subject to limitations of available human-health benchmarks).

  16. Methanol ice VUV photoprocessing: GC-MS analysis of volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Abou Mrad, Ninette; Duvernay, Fabrice; Chiavassa, Thierry; Danger, Grégoire

    2016-05-01

    Next to water, methanol is one of the most abundant molecules in astrophysical ices. A new experimental approach is presented here for the direct monitoring via gas chromatography coupled to mass spectrometry (GC-MS) of a sublimating photoprocessed pure methanol ice. Unprecedentedly, in a same analysis, compelling evidences for the formation of 33 volatile organic compounds are provided. The latter are C1-C6 products including alcohols, aldehydes, ketones, esters, ethers and carboxylic acids. Few C3 and all C4 detected compounds have been identified for the first time. Tentative detections of few C5 and C6 compounds are also presented. GC-MS allows for the first time the direct quantification of C2-C4 photoproducts and shows that their abundances decrease with the increase of their carbon chain length. These qualitative and quantitative measurements provide important complementary results to previous experiments, and present interesting similarities with observations of sources rich in methanol.

  17. SEMI-VOLATILE ORGANIC ACIDS AND OTHER POLAR COMPOUNDS COLLECTED IN NEW YORK CITY IN RESPONSE TO THE EVENTS OF 9/11

    EPA Science Inventory

    Concentrations of over 25 polar semi-volatile and non-volatile organic compounds were measured in Lower Manhattan, New York using a high capacity Integrated Organic Gas and Particle sampler, after the initial destruction of the World Trade Center. The polar organic compounds in...

  18. EXTRACTION METHODS FOR RECOVERY OF VOLATILE ORGANIC COMPOUNDS FROM FORTIFIED DRY SOILS

    EPA Science Inventory

    Recovery of 8 volatile organic compounds (VOCs) from dry soils, each fortified at 800 ng/g soil, was studied in relation to the extraction method and time of extraction. Extraction procedures studied on desiccator-dried soils were modifications of EPA low-and high-level purge-and...

  19. Purgeable organic compounds in ground water at the Idaho National Engineering Laboratory, Idaho; 1988 and 1989

    USGS Publications Warehouse

    Mann, L.J.

    1990-01-01

    Groundwater samples from 38 wells at the Idaho National Engineering Laboratory were analyzed for 36 purgeable organic compounds in 1988-89. Thirty-six of the wells obtain water from the Snake River Plain aquifer and were equipped with dedicated or portable pumps. Water samples from one well that obtains water from the aquifer and one that obtains water from a perched groundwater zone were collected using a thief sampler. Analyses of water from 22 wells indicated the aquifer locally contained detectable concentrations of at least 1 of 19 purgeable organic compounds, mainly carbon tetrachloride, 1,1,1-trichloroethane, and trichloroethylene. Except for five wells, the maximum concentration of a specific compound in groundwater was 6.4 microgram/L or less; concentrations of most compounds were less than 0.2 microgram/L. Water from four wells at and near the Test Area North contained from 44 to 29, 000 micrograms/L of trichloroethylene. Water from a well that obtains water from a discontinuous perched groundwater zone at the Radioactive Waste Management Complex contained 1,400 micrograms/L of carbon tetrachloride, 940 micrograms/L of chloroform, 250 micrograms/L of 1,1,1- trichloroethane, and 1,100 micrograms/L trichloroethylene. Selected purgeable organic compounds, such as total xylene and methylene chloride, were detected in some groundwater samples and some blank samples consisting of boiled deionized water. Their presence in the blank samples suggest the compounds could have been inadvertently introduced into the groundwater sampled during or subsequent to collection. (USGS)

  20. HENRY'S LAW CONSTANTS AND MICELLAR PARTITIONING OF VOLATILE ORGANIC COMPOUNDS IN SURFACTANT SOLUTIONS

    EPA Science Inventory

    Partitioning of volatile organic compounds (VOCs) into surfactant micelles affects the apparent vapor-liquid equilibrium of VOCs in surfactant solutions. This partitioning will complicate removal of VOCs from surfactant solutions by standard separation processes. Headspace expe...

  1. Filtration of water-sediment samples for the determination of organic compounds

    USGS Publications Warehouse

    Sandstrom, Mark W.

    1995-01-01

    This report describes the equipment and procedures used for on-site filtration of surface-water and ground-water samples for determination of organic compounds. Glass-fiber filters and a positive displacement pumping system are suitable for processing most samples for organic analyses. An optional system that uses disposable in-line membrane filters is suitable for a specific gas chromatography/mass spectrometry, selected-ion monitoring analytical method for determination of organonitrogen herbicides. General procedures to minimize contamination of the samples include preparing a clean workspace at the site, selecting appropriate sample-collection materials, and cleaning of the equipment with detergent, tap water, and methanol.

  2. The search for organic substances and inorganic volatile compounds in the surface of Mars

    NASA Technical Reports Server (NTRS)

    Biemann, K.; Oro, J.; Toulmin, P., III; Orgel, L. E.; Nier, A. O.; Anderson, D. M.; Flory, D.; Diaz, A. V.; Rushneck, D. R.; Simmonds, P. G.

    1977-01-01

    A total of four Martian samples, one surface and one subsurface sample at each of the two Viking landing sites, Chryse Planitia and Utopia Planitia, have been analyzed for organic compounds by a gas chromatograph-mass spectrometer. In none of these experiments could organic material of Martian origin be detected at detection limits generally of the order of parts per billion and for a few substances closer to parts per million. The evolution of water and carbon dioxide, but not of other inorganic gases, was observed upon heating the sample to temperatures of up to 500 C. The absence of organic compounds seems to preclude their production on the planet at rates that exceed the rate of their destruction. It also makes it unlikely that living systems that behave in a manner similar to terrestrial biota exist, at least at the two Viking landing sites.

  3. Field guide for collecting samples for analysis of volatile organic compounds in stream water for the National Water-Quality Assessment Program

    USGS Publications Warehouse

    Shelton, Larry R.

    1997-01-01

    For many years, stream samples for analysis of volatile organic compounds have been collected without specific guidelines or a sampler designed to avoid analyte loss. In 1996, the U.S. Geological Survey's National Water-Quality Assessment Program began aggressively monitoring urban stream-water for volatile organic compounds. To assure representative samples and consistency in collection procedures, a specific sampler was designed to collect samples for analysis of volatile organic compounds in stream water. This sampler, and the collection procedures, were tested in the laboratory and in the field for compound loss, contamination, sample reproducibility, and functional capabilities. This report describes that sampler and its use, and outlines field procedures specifically designed to provide contaminant-free, reproducible volatile organic compound data from stream-water samples. These guidelines and the equipment described represent a significant change in U.S. Geological Survey instructions for collecting and processing stream-water samples for analysis of volatile organic compounds. They are intended to produce data that are both defensible and interpretable, particularly for concentrations below the microgram-per-liter level. The guidelines also contain detailed recommendations for quality-control samples.

  4. Influence of soil organic matter composition on the partition of organic compounds

    USGS Publications Warehouse

    Rutherford, D.W.; Chiou, C.T.; Klle, D.E.

    1992-01-01

    The sorption at room temperature of benzene and carbon tetrachloride from water on three high-organic-content soils (muck, peat, and extracted peat) and on cellulose was determined in order to evaluate the effect of sorbent polarity on the solute partition coefficients. The isotherms are highly linear for both solutes on all the organic matter samples, which is consistent with a partition model. For both solutes, the extracted peat shows the greatest sorption capacity while the cellulose shows the lowest capacity; the difference correlates with the polar-to-nonpolar group ratio [(O + N)/C] of the sorbent samples. The relative increase of solute partition coefficient (Kom) with a decrease of sample polar content is similar for both solutes, and the limiting sorption capacity on a given organic matter sample is comparable between the solutes. This observation suggests that one can estimate the polarity effect of a sample of soil organic matter (SOM) on Kom of various nonpolar solutes by determining the partition coefficient of single nonpolar solute when compositional analysis of the SOM is not available. The observed dependence of Kom on sample polarity is used to account for the variation of Kom values of individual compounds on different soils that results from change in the polar group content of SOM. On the assumption that the carbon content of SOM in "ordinary soils" is 53-63%, the calculated variation of Kom is a factor of ???3. This value is in agreement with the limit of variation of most Kom data with soils of relatively high SOM contents.

  5. Predicting transformation products from the direct photolysis of organic compounds in aquatic systems

    EPA Science Inventory

    Direct photolysis is an important degradation pathway for organic compounds bearing sunlight-absorbing chromophores in aquatic systems. An ever-growing body of process science underlying direct photolysis transformation pathways provides the basis for the development of predictiv...

  6. Native Fluorescence Detection Methods, Devices, and Systems for Organic Compounds

    NASA Technical Reports Server (NTRS)

    Hug, William F. (Inventor); Bhartia, Rohit (Inventor); Lane, Arthur L. (Inventor); Reid, Ray D. (Inventor)

    2018-01-01

    Naphthalene, benzene, toluene, xylene, and other volatile organic compounds VOCs have been identified as serious health hazards. Embodiments of the invention are directed to methods and apparatus for near-real-time in-situ detection and accumulated dose measurement of exposure to naphthalene vapor and other hazardous gaseous VOCs. The methods and apparatus employ excitation of fluorophors native or endogenous to compounds of interest using light sources emitting in the ultraviolet below 300 nm and measurement of native fluorescence emissions in distinct wavebands above the excitation wavelength. The apparatus of some embodiments are cell-phone-sized sensor/dosimeter "badges" to be worn by personnel potentially exposed to hazardous VOCs. The badge sensor of some embodiments provides both real time detection and data logging of exposure to naphthalene or other VOCs of interest from which both instantaneous and accumulated dose can be determined.

  7. Native Fluorescence Detection Methods, Devices, and Systems for Organic Compounds

    NASA Technical Reports Server (NTRS)

    Hug, William F. (Inventor); Reid, Ray D. (Inventor); Lane, Arthur L. (Inventor); Bhartia, Rohit (Inventor)

    2016-01-01

    Naphthalene, benzene, toluene, xylene, and other volatile organic compounds VOCs have been identified as serious health hazards. Embodiments of the invention are directed to methods and apparatus for near-real-time in-situ detection and accumulated dose measurement of exposure to naphthalene vapor and other hazardous gaseous VOCs. The methods and apparatus employ excitation of fluorophors native or endogenous to compounds of interest using light sources emitting in the ultraviolet below 300 nm and measurement of native fluorescence emissions in distinct wavebands above the excitation wavelength. The apparatus of some embodiments are cell-phone-sized sensor/dosimeter "badges" to be worn by personnel potentially exposed to hazardous VOCs. The badge sensor of some embodiments provides both real time detection and data logging of exposure to naphthalene or other VOCs of interest from which both instantaneous and accumulated dose can be determined.

  8. Fate of Volatile Organic Compounds in Constructed Wastewater Treatment Wetlands

    USGS Publications Warehouse

    Keefe, S.H.; Barber, L.B.; Runkel, R.L.; Ryan, J.N.

    2004-01-01

    The fate of volatile organic compounds was evaluated in a wastewater-dependent constructed wetland near Phoenix, AZ, using field measurements and solute transport modeling. Numerically based volatilization rates were determined using inverse modeling techniques and hydraulic parameters established by sodium bromide tracer experiments. Theoretical volatilization rates were calculated from the two-film method incorporating physicochemical properties and environmental conditions. Additional analyses were conducted using graphically determined volatilization rates based on field measurements. Transport (with first-order removal) simulations were performed using a range of volatilization rates and were evaluated with respect to field concentrations. The inverse and two-film reactive transport simulations demonstrated excellent agreement with measured concentrations for 1,4-dichlorobenzene, tetrachloroethene, dichloromethane, and trichloromethane and fair agreement for dibromochloromethane, bromo-dichloromethane, and toluene. Wetland removal efficiencies from inlet to outlet ranged from 63% to 87% for target compounds.

  9. Identifying organic nitrogen compounds in Rocky Mountain National Park aerosols

    NASA Astrophysics Data System (ADS)

    Beem, K. B.; Desyaterik, Y.; Ozel, M. Z.; Hamilton, J. F.; Collett, J. L.

    2010-12-01

    Nitrogen deposition is an important issue in Rocky Mountain National Park (RMNP). While inorganic nitrogen contributions to the ecosystems in this area have been studied, the sources of organic nitrogen are still largely unknown. To better understand the potential sources of organic nitrogen, filter samples were collected and analyzed for organic nitrogen species. Samples were collected in RMNP using a Thermo Fisher Scientific TSP (total suspended particulate) high-volume sampler with a PM2.5 impactor plate from April - November of 2008. The samples presented the opportunity to compare two different methods for identification of individual organic nitrogen species. The first type of analysis was performed with a comprehensive two dimensional gas chromatography (GCxGC) system using a nitrogen chemiluminescence detector (NCD). The filter samples were spiked with propanil in dichloromethane to use as an internal standard and were then extracted in water followed by solid phase extraction. The GCxGC system was comprised of a volatility based separation (DB5 column) followed by a polarity based separation (RXI-17 column). A NCD was used to specifically detect nitrogen compounds and remove the complex background matrix. Individual standards were used to identify peaks by comparing retention times. This method has the added benefit of an equimolar response for nitrogen so only a single calibration is needed for all species. In the second analysis, a portion of the same filter samples were extracted in DI water and analyzed with liquid chromatography coupled with mass spectroscopy (LC/MS). The separation was performed using a C18 column and a water-methanol gradient elution. Electrospray ionization into a time of flight mass spectrometer was used for detection. High accuracy mass measurement allowed unambiguous assignments of elemental composition of resulting ions. Positive and negative polarities were used since amines tend to show up in positive mode and nitrates in

  10. The Impact and Oxidation Survival of Selected Meteoritic Compounds: Signatures of Asteroid Organic Material on Planetary Surfaces

    NASA Technical Reports Server (NTRS)

    Cooper, George; Horz, Fred; Oleary, Alanna; Chang, Sherwood

    2013-01-01

    Polar, non-volatile organic compounds may be present on the surfaces (or near surfaces) of multiple Solar System bodies. If found, by current or future missions, it would be desirable to determine the origin(s) of such compounds, e.g., asteroidal or in situ. To test the possible survival of meteoritic compounds both during impacts with planetary surfaces and under subsequent (possibly) harsh ambient conditions, we subjected known meteoritic compounds to relatively high impact-shock pressures and/or to varying oxidizing/corrosive conditions. Tested compounds include sulfonic and phosphonic acids (S&P), polyaromatic hydrocarbons (PAHs) amino acids, keto acids, dicarboxylic acids, deoxy sugar acids, and hydroxy tricarboxylic acids (Table 1). Meteoritic sulfonic acids were found to be relatively abundant in the Murchison meteorite and to possess unusual S-33 isotope anomalies (non mass-dependent isotope fractionations). Combined with distinctive C-S and C-P bonds, the S&P are potential signatures of asteroidal organic material.

  11. Sorption of organic compounds by aged polystyrene microplastic particles.

    PubMed

    Hüffer, Thorsten; Weniger, Anne-Katrin; Hofmann, Thilo

    2018-05-01

    Microplastics that are released into the environment undergo aging and interact with other substances such as organic contaminants. Understanding the sorption interactions between aged microplastics and organic contaminants is therefore essential for evaluating the impact of microplastics on the environment. There is little information available on how the aging of microplastics affects their sorption behavior and other properties. We have therefore investigated the effects of an accelerated UV-aging procedure on polystyrene microplastics, which are used in products such as skin cleaners and foams. Physical and chemical particle characterizations showed that aging led to significant surface oxidation and minor localized microcrack formation. Sorption coefficients of organic compounds by polystyrene microplastics following aging were up to one order of magnitude lower than for pristine particles. Sorption isotherms were experimentally determined using a diverse set of probe sorbates covering a variety of substance classes allowing an in-depth evaluation of the poly-parameter linear free-energy relationship (ppLFER) modelling used to investigate the contribution of individual molecular interactions to overall sorption. The ppLFER modelling was validated using internal cross-validation, which confirmed its robustness. This approach therefore yields improved estimates of the interactions between aged polystyrene microplastics and organic contaminants. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. NATURAL EMISSIONS OF NON-METHANE VOLATILE ORGANIC COMPOUNDS, CARBON MONOXIDE, AND OXIDES OF NITROGEN FROM NORTH AMERICA

    EPA Science Inventory

    The magnitudes, distributions, controlling processes and uncertainties associated with North American natural emissions of oxidant precursors are reviewed. Natural emissions are repsonsible for a major portion of the compounds, including non-methane volatile organic compounds (N...

  13. Surfactant effects on desorption rate of nonionic organic compounds from soils to water

    USGS Publications Warehouse

    Cesare, David Di; Smith, James A.

    1994-01-01

    The widespread occurrence of organic contamination in groundwater systems has become an important environmental concern. Of particular interest are nonionic organic compounds, which sorb strongly to natural soil as a result of their characteristic low aqueous solubilities and hydrophobic nature. Consequently, the remediation of nonionic organic contamination in groundwater systems is often highly dependent on contaminant desorption from the sorbed to aqueous phase. The kinetics of desorption will significantly influence the extraction efficiency of pump-and-treat remedial methods that are capable of removing only dissolved phase contaminants.

  14. Organic compounds in White River water used for public supply near Indianapolis, Indiana, 2002-05

    USGS Publications Warehouse

    Lathrop, Tim; Moran, Dan

    2011-01-01

    The National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey (USGS) characterized the occurrence of 277 organic compounds in source water (stream water collected before treatment) and finished water (treated water before distribution) from the White River North treatment plant, one of several community water systems that use the White River as its primary water supply (fig. 1). Samples were collected at least monthly during 2002-05 and included 30 source- and 13 finished-water samples. The samples were analyzed for pesticides and selected pesticide degradates (or 'breakdown products'), solvents, gasoline hydrocarbons, disinfection by-products, personal-care and domestic-use products, and other organic compounds. Community water systems are required to monitor for compounds regulated under the Safe Drinking Water Act. Most of the compounds tested in this study are not regulated under U.S. Environmental Protection Agency (USEPA) federal drinking-water standards (U.S. Environmental Protection Agency, 2007a). The White River study is part of the ongoing Source Water-Quality Assessment (SWQA) investigation of community water systems that withdraw from rivers across the United States. More detailed information and references on the sampling-design methodology, specific compounds monitored, and the national study are described by Carter and others (2007).

  15. Impact of elevated CO2 and O3 concentrations on biogenic volatile organic compounds emissions from Ginkgo biloba.

    PubMed

    Li, Dewen; Chen, Ying; Shi, Yi; He, Xingyuan; Chen, Xin

    2009-04-01

    In natural environment with ambient air, ginkgo trees emitted volatile organic compounds 0.18 microg g(-1) h(-1) in July, and 0.92 microg g(-1) h(-1) in September. Isoprene and limonene were the most abundant detected compounds. In September, alpha-pinene accounted for 22.5% of the total. Elevated CO(2) concentration in OTCs increased isoprene emission significantly in July (p<0.05) and September (p<0.05), while the total monoterpenes emission was enhanced in July and decreased in September by elevated CO(2). Exposed to elevated O(3) increased the isoprene and monoterpenes emissions in July and September, and the total volatile organic compounds emission rates were 0.48 microg g(-1) h(-1) (in July) and 2.24 microg g(-1) h(-1) (in September), respectively. The combination of elevated CO(2) and O(3) did not have any effect on biogenic volatile organic compounds emissions, except increases of isoprene and Delta3-carene in September.

  16. A study on heterogeneous photocatalytic degradation of various organic compounds using N-Tio2 under Uv-light irradiation

    NASA Astrophysics Data System (ADS)

    Srujana, Dhegam; Sailu, Chinta

    2018-04-01

    The aim of this work is to determine the photocatalytic degradation of mixture of four selected organic compounds are Congo Red (CR), Methylene Blue (MB), Diclofenaec (DC), 4-Chlorophenol (4-CP) have been subjected to Photo catalytic degradation by Ultraviolet (λ=254nm) radiation in presence of Nitrogen-doped Titanium dioxide (N-TiO2) catalyst. This paper focused on the enhancement of photo catalysis by modification of TiO2 employing non-metal ion (Nitrogen) doping. Experiments are conducted with a mixture of equal proportions of organic compounds (CR, MB, DC, and 4-CP) with combined concentrations of 10, 20, 30, 40 and 50 mg/l in water in a batch reactor in presence of N-TiO2catalyst with UV light (λ=254nm). The rate of degradation of each compound is determined by using spectrophotometer. The kinetics of degradation of the selected organic compounds is followed first order rate.

  17. For Profit Organizations Showing Signs of Turnaround: Twenty-Fourth Annual Status Report on for Profit Child Care

    ERIC Educational Resources Information Center

    Neugebauer, Roger; Hartzell, Debra

    2011-01-01

    The year 2010 will not be remembered as a banner year for large for profit child care organizations. But it appears that heading into 2011, optimism has returned. This article presents the twenty-fourth annual status report on for profit child care organizations. In 2010, the total capacity of the three largest for profit chains in North America,…

  18. Micro-ion Traps for Detection of (Pre)-Biotic Organic Compounds on Comets

    NASA Technical Reports Server (NTRS)

    vanAmerom, Friso H. W.; Chaudhary, A.; Short, R. T.; Brinkerhoff, William; Glavin, Daniel; Mahaffy, Paul R.; Roman, Patrick A.

    2013-01-01

    Comets are currently believed to be a mixture of interstellar and nebular material. Many of the volatiles in comets are attributed to interstellar chemistry, because the same species of carbonaceous compounds are also observed in ices in interstellar molecular (ISM) clouds. Comets are thus likely to be a relatively pristine reservoir of primitive material and carbonaceous compounds in our solar system. They could be a major contributor to the delivery of prebiotic organic compounds, from which life emerged through impacts on early Earth. Mass spectrometers are very powerful tools to identify unknown chemicals, and much progress bas been made in miniaturizing mas spectrometers for space applications. Most miniatu rized mass spectrometers developed to date, however, are still relatively large, power hungry, complicated to assemble, and would have significant impact on space flight vehicle total payload and resource allocations.

  19. Energy dependence of radiation interaction parameters of some organic compounds

    NASA Astrophysics Data System (ADS)

    Singh, Mohinder; Tondon, Akash; Sandhu, B. S.; Singh, Bhajan

    2018-04-01

    Gamma rays interact with a material through photoelectric absorption, Compton scattering, Rayleigh scattering and Pair production in the intermediate energy range. The probability of occurrence of a particular type of process depends on the energy of incident gamma rays, atomic number of the material, scattering angle and geometrical conditions. Various radiological parameters for organic compounds, namely ethylene glycol (C2H6O2), propylene glycol (C3H8O2), glycerin (C3H8O3), isoamyl alcohol (C5H12O), butanone (C4H8O), acetophenone (C8H8O2), cyclohexanone (C6H10O), furfural (C5H4O2), benzaldehyde (C7H6O), cinnamaldehyde (C9H8O), glutaraldehyde (C5H8O2), aniline (C6H7N), benzyl amine (C6H7N), nitrobenzene (C6H5NO2), ethyl benzene (C8H10), ethyl formate (C3H6O2) and water (H2O) are presented at 81, 122, 356 and 511 keV energies employing NaI(Tl) scintillation detector in narrow-beam transmission geometry. The radiation interaction parameters such as mass attenuation, molar extinction and mass energy absorption coefficients, half value layer, total atomic and effective electronic cross-sections and CT number have been evaluated for these organic compounds. The general trend of values of mass attenuation coefficients, half value layer, molar extinction coefficients, total atomic and effective electronic cross-sections and mass energy absorption coefficients shows a decrease with increase in incident gamma photon energy. The values of CT number are found to increases linearly with increase of effective atomic number (Zeff). The variation in CT number around Zeff ≈ 3.3 shows the peak like structure with respect to water and the correlation between CT number and linear attenuation coefficient is about 0.99. Appropriate equations are fitted to these experimentally determined parameters for the organic compounds at incident photon energy ranging from 81 keV to 511 keV used in the present study. Experimental values are compared with the theoretical data obtained using Win

  20. Organic compounds used in animal husbandry: Chapter 13

    USGS Publications Warehouse

    Wershaw, Robert L.; Shore, Laurence S.; Pruden, Amy; Shore, Laurence S.

    2009-01-01

    Although in general, the same drugs are used by humans as for animal husbandry, some compounds are unique to CAFOs. In raising and fattening steers, anabolic steroids are widely used in the US. In the cattle industry, large use is made of the acaricides, avermectins, and the cypermethrins as well as juvenile growth hormone inhibitor for fly and tick control that could affect soil fauna in very small quantities as they reach the environment without any modification. In poultry, the organic arsenides have been widely used for decades to control coccidiosis and increase growth. The environmental fate of the arsenic excreted in the poultry feces is therefore been an area of concern.

  1. Analysis of volatile organic compounds in pleural effusions by headspace solid-phase microextraction coupled with cryotrap gas chromatography and mass spectrometry.

    PubMed

    Huang, Zhongping; Zhang, Jie; Zhang, Peipei; Wang, Hong; Pan, Zaifa; Wang, Lili

    2016-07-01

    Headspace solid-phase microextraction coupled with cryotrap gas chromatography and mass spectrometry was applied to the analysis of volatile organic compounds in pleural effusions. The highly volatile organic compounds were separated successfully with high sensitivity by the employment of a cryotrap device, with the construction of a cold column head by freezing a segment of metal capillary with liquid nitrogen. A total of 76 volatile organic compounds were identified in 50 pleural effusion samples (20 malignant effusions and 30 benign effusions). Among them, 34 more volatile organic compounds were detected with the retention time less than 8 min, by comparing with the normal headspace solid-phase microextraction coupled with gas chromatography and mass spectrometry method. Furthermore, 24 volatile organic compounds with high occurrence frequency in pleural effusion samples, 18 of which with the retention time less than 8 min, were selected for the comparative analysis. The results of average peak area comparison and box-plot analysis showed that except for cyclohexanone, 2-ethyl-1-hexanol, and tetramethylbenzene, which have been reported as potential cancer biomarkers, cyclohexanol, dichloromethane, ethyl acetate, n-heptane, ethylbenzene, and xylene also had differential expression between malignant and benign effusions. Therefore, the proposed approach was valuable for the comprehensive characterization of volatile organic compounds in pleural effusions. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Microbial Electrosynthesis: Feeding Microbes Electricity To Convert Carbon Dioxide and Water to Multicarbon Extracellular Organic Compounds

    PubMed Central

    Nevin, Kelly P.; Woodard, Trevor L.; Franks, Ashley E.; Summers, Zarath M.; Lovley, Derek R.

    2010-01-01

    The possibility of providing the acetogenic microorganism Sporomusa ovata with electrons delivered directly to the cells with a graphite electrode for the reduction of carbon dioxide to organic compounds was investigated. Biofilms of S. ovata growing on graphite cathode surfaces consumed electrons with the reduction of carbon dioxide to acetate and small amounts of 2-oxobutyrate. Electrons appearing in these products accounted for over 85% of the electrons consumed. These results demonstrate that microbial production of multicarbon organic compounds from carbon dioxide and water with electricity as the energy source is feasible. PMID:20714445

  3. The Enantiomeric Ratios of Meteoritic Organic Compounds: Their Possible Roles in the Origin of Life

    NASA Technical Reports Server (NTRS)

    Cooper, George

    2012-01-01

    This talk will give an overview of the enantiomer (mirror-image) ratios of organic compounds in meteorites and also describe the results of the present work in my lab. The primary focus will be on sugar derivatives (sugar acids) of carbonaceous meteorites. Our work begins to address questions associated with chirality, i.e., the origins of homochirality. On Earth, biological monomers (amino acids, sugars, etc.) are usually found with one of the enantiomers more abundant than the other. However, biological polymers (proteins, nucleic acids, etc.) are only composed of one enantiomer i.e., they are homochiral. There are hints in meteorites that some organic molecules may also exist in homochiral forms. The talk will address questions such as: did extraterrestrial sources aid in the beginning of this homochirality? Do the increasing size and apparent enantiomer excesses of some meteoritic compounds also extend to larger meteoritic compounds and polymers?

  4. Effects of gas-wall partitioning in Teflon tubing and instrumentation on time-resolved measurements of gas-phase organic compounds

    NASA Astrophysics Data System (ADS)

    Pagonis, Demetrios; Krechmer, Jordan E.; de Gouw, Joost; Jimenez, Jose L.; Ziemann, Paul J.

    2017-12-01

    Recent studies have demonstrated that organic compounds can partition from the gas phase to the walls in Teflon environmental chambers and that the process can be modeled as absorptive partitioning. Here these studies were extended to investigate gas-wall partitioning of organic compounds in Teflon tubing and inside a proton-transfer-reaction mass spectrometer (PTR-MS) used to monitor compound concentrations. Rapid partitioning of C8-C14 2-ketones and C11-C16 1-alkenes was observed for compounds with saturation concentrations (c∗) in the range of 3 × 104 to 1 × 107 µg m-3, causing delays in instrument response to step-function changes in the concentration of compounds being measured. These delays vary proportionally with tubing length and diameter and inversely with flow rate and c∗. The gas-wall partitioning process that occurs in tubing is similar to what occurs in a gas chromatography column, and the measured delay times (analogous to retention times) were accurately described using a linear chromatography model where the walls were treated as an equivalent absorbing mass that is consistent with values determined for Teflon environmental chambers. The effect of PTR-MS surfaces on delay times was also quantified and incorporated into the model. The model predicts delays of an hour or more for semivolatile compounds measured under commonly employed conditions. These results and the model can enable better quantitative design of sampling systems, in particular when fast response is needed, such as for rapid transients, aircraft, or eddy covariance measurements. They may also allow estimation of c∗ values for unidentified organic compounds detected by mass spectrometry and could be employed to introduce differences in time series of compounds for use with factor analysis methods. Best practices are suggested for sampling organic compounds through Teflon tubing.

  5. The Formation of Complex Organic Compounds in Astrophysical Ices and their Implications for Astrobiology

    NASA Technical Reports Server (NTRS)

    Sandford, Scott A.

    2015-01-01

    Ices in astrophysical environments are generally dominated by very simple molecules like H2O, CH3OH, CH4, NH3, CO, CO2, etc, although they likely contain PAHs as well. These molecules, particularly H2O, are of direct interest to astrobiology in-and-of themselves since they represent some of the main carriers of the biogenic elements C, H, O, and N. In addition, these compounds are present in the dense interstellar clouds in which new stars and planetary systems are formed and may play a large role in the delivery of volatiles and organics to the surfaces of new planets. However, these molecules are all far simpler than the more complex organic compounds found in living systems.

  6. FINAL REPORT: MEMBRANE-MEDIATED EXTRACTION AND BIODEGRADATION OF VOLATILE ORGANIC COMPOUNDS FROM AIR

    EPA Science Inventory

    The report describes feasibility tests of a two-step strategy for air pollution control applicable to exhaust air contaminated with volatile organic compounds (VOCs) from painting aircraft. In the first step, the VOC-contaminated air passes over coated, polypropylene, hollow-fibe...

  7. Elevated levels of diesel range organic compounds in groundwater near Marcellus gas operations are derived from surface activities.

    PubMed

    Drollette, Brian D; Hoelzer, Kathrin; Warner, Nathaniel R; Darrah, Thomas H; Karatum, Osman; O'Connor, Megan P; Nelson, Robert K; Fernandez, Loretta A; Reddy, Christopher M; Vengosh, Avner; Jackson, Robert B; Elsner, Martin; Plata, Desiree L

    2015-10-27

    Hundreds of organic chemicals are used during natural gas extraction via high-volume hydraulic fracturing (HVHF). However, it is unclear whether these chemicals, injected into deep shale horizons, reach shallow groundwater aquifers and affect local water quality, either from those deep HVHF injection sites or from the surface or shallow subsurface. Here, we report detectable levels of organic compounds in shallow groundwater samples from private residential wells overlying the Marcellus Shale in northeastern Pennsylvania. Analyses of purgeable and extractable organic compounds from 64 groundwater samples revealed trace levels of volatile organic compounds, well below the Environmental Protection Agency's maximum contaminant levels, and low levels of both gasoline range (0-8 ppb) and diesel range organic compounds (DRO; 0-157 ppb). A compound-specific analysis revealed the presence of bis(2-ethylhexyl) phthalate, which is a disclosed HVHF additive, that was notably absent in a representative geogenic water sample and field blanks. Pairing these analyses with (i) inorganic chemical fingerprinting of deep saline groundwater, (ii) characteristic noble gas isotopes, and (iii) spatial relationships between active shale gas extraction wells and wells with disclosed environmental health and safety violations, we differentiate between a chemical signature associated with naturally occurring saline groundwater and one associated with alternative anthropogenic routes from the surface (e.g., accidental spills or leaks). The data support a transport mechanism of DRO to groundwater via accidental release of fracturing fluid chemicals derived from the surface rather than subsurface flow of these fluids from the underlying shale formation.

  8. Elevated levels of diesel range organic compounds in groundwater near Marcellus gas operations are derived from surface activities

    PubMed Central

    Drollette, Brian D.; Hoelzer, Kathrin; Warner, Nathaniel R.; Darrah, Thomas H.; Karatum, Osman; O’Connor, Megan P.; Nelson, Robert K.; Fernandez, Loretta A.; Reddy, Christopher M.; Vengosh, Avner; Jackson, Robert B.; Elsner, Martin; Plata, Desiree L.

    2015-01-01

    Hundreds of organic chemicals are used during natural gas extraction via high-volume hydraulic fracturing (HVHF). However, it is unclear whether these chemicals, injected into deep shale horizons, reach shallow groundwater aquifers and affect local water quality, either from those deep HVHF injection sites or from the surface or shallow subsurface. Here, we report detectable levels of organic compounds in shallow groundwater samples from private residential wells overlying the Marcellus Shale in northeastern Pennsylvania. Analyses of purgeable and extractable organic compounds from 64 groundwater samples revealed trace levels of volatile organic compounds, well below the Environmental Protection Agency’s maximum contaminant levels, and low levels of both gasoline range (0–8 ppb) and diesel range organic compounds (DRO; 0–157 ppb). A compound-specific analysis revealed the presence of bis(2-ethylhexyl) phthalate, which is a disclosed HVHF additive, that was notably absent in a representative geogenic water sample and field blanks. Pairing these analyses with (i) inorganic chemical fingerprinting of deep saline groundwater, (ii) characteristic noble gas isotopes, and (iii) spatial relationships between active shale gas extraction wells and wells with disclosed environmental health and safety violations, we differentiate between a chemical signature associated with naturally occurring saline groundwater and one associated with alternative anthropogenic routes from the surface (e.g., accidental spills or leaks). The data support a transport mechanism of DRO to groundwater via accidental release of fracturing fluid chemicals derived from the surface rather than subsurface flow of these fluids from the underlying shale formation. PMID:26460018

  9. 77 FR 62396 - Annual Company-Run Stress Test Requirements for Banking Organizations With Total Consolidated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-12

    ... in the stress test, for each quarter of the planning horizon, aggregate losses, pre-provision net... Company-Run Stress Test Requirements for Banking Organizations With Total Consolidated Assets Over $10... regulatory agency to conduct stress tests on an annual basis. The Board is adopting this final rule to...

  10. Organic compounds of PM2.5 in Mexico Valley: spatial and temporal patterns, behavior and sources.

    PubMed

    Amador-Muñoz, O; Villalobos-Pietrini, R; Miranda, J; Vera-Avila, L E

    2011-03-15

    A longitudinal study on spatial and temporal behavior of particles less than 2.5 μm (PM(2.5)), solvent extracted organic matter (SEOM), polycyclic aromatic hydrocarbons (PAH), n-alkanes and nitro-PAH was carried out for a full year in 2006, at five sites simultaneously around the Metropolitan Zone of Mexico Valley (MZMV). There is rather uniform distribution of PM(2.5) and SEOM in the MZMV regarding gravimetric mass concentration, while some specific organic chemical components showed mass heterogeneity. The highest mass concentrations of target compounds occurred in the dry seasons with respect to the rainy season. Bonfires and fireworks are probably responsible for extreme values of PM(2.5), SEOM and PAH (≥ 228 gmol(-1)). Benzo[ghi]perylene was the most abundant PAH, with C(24)-C(26) the most abundant n-alkanes and 2-nitrofluoranthene and 9-nitroanthracene the most abundant nitro-PAH. The northeast zone was the area with the greatest presence of sources of incomplete diesel combustion, while the central for gasoline combustion. In the southwest, the biogenic sources were more abundant over the anthropogenic sources. This was opposite to the other sites. Factor analysis allowed us to relate different compounds to emitting sources. Three main factors were associated with combustion, pyrolysis and biogenic primary sources while the other factors were associated with secondary organic aerosol formation and industry. Correlation analyses indicated that SEOM originates from different primary emission sources or is formed by different processes than the other variables, except in southwest. Associations among variables suggest that PM(2.5) in the northwest and in the southeast originated mainly from primary emissions or consisted of primary organic compounds. PM(2.5) in the northeast, central and southwest contains a greater proportion of secondary organic compounds, with the less oxidized organic aerosols in the northeast and the most aged organic aerosol in the

  11. Influences of chlorine content on emission of HCl and organic compounds in waste incineration using fluidized beds.

    PubMed

    Wey, M Y; Liu, K Y; Yu, W J; Lin, C L; Chang, F Y

    2008-01-01

    HCl and some organic compounds are the precursors of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) in municipal solid waste incinerators. In this work, a lab-scale fluidized bed incinerator is adopted to study the relationship between the organic and the inorganic chlorine contents of artificial wastes and the emissions of HCl and organic compounds. The lower threshold limit (LTL) of chlorine content below which HCl and organic compounds are not generated is studied. Experimental results showed that organic chlorides had a greater potential to release chlorine than inorganic chlorides. The generation of organic pollutants fell, but the emissions of HCl increased with the temperature. The concentrations of chlorophenols (CPs)/chlorobenzenes (CBs) increased with chlorine contents. No LTL existed for HCl regardless of whether CaO was added. The LTL for CPs was between 0.1 and 0.3wt% of inorganic chloride, but there was none for organic sources. For CBs, the LTL was between 0.5 and 1.0wt% for inorganics at 700 and 800 degrees C, but 0.1-0.3 wt% at 700 degrees C and 0.3-0.5 wt% at 800 degrees C for organics. The production of PAHs and benzene, toluene, ethylbenzene and xylene (BTEX) was related to the surplus hydrogen ions that were not reacted with the chlorine. Adding CaO inhibited the production of HCl, CBs and CPs, but did not seriously affect PAHs and BTEX.

  12. Novel synthetic organic compounds inspired from antifeedant marine alkaloids as potent bacterial biofilm inhibitors.

    PubMed

    Rane, Rajesh A; Karpoormath, Rajshekhar; Naphade, Shital S; Bangalore, Pavankumar; Shaikh, Mahamadhanif; Hampannavar, Girish

    2015-08-01

    In this paper, we have reported seventeen novel synthetic organic compounds derived from marine bromopyrrole alkaloids, exhibiting potential inhibition of biofilm produced by Gram-positive bacteria. Compound 5f with minimumbiofilm inhibitory concentration(MBIC) of 0.39, 0.78 and 3.125 μg/mL against MSSA, MRSA and SE respectively, emerged as promising anti-biofilm lead compounds. In addition, compounds 5b, 5c, 5d, 5e, 5f, 5h, 5i and 5j revealed equal potency as that of the standard drug Vancomycin (MBIC = 3.125 μg/mL) against Streptococcus epidermidis. Notably, most of the synthesized compounds displayed better potency than Vancomycin indicating their potential as inhibitors of bacterial biofilm. The cell viability assay for the most active hybrid confirms its anti-virulence properties which need to be further researched. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Exploring sources of biogenic secondary organic aerosol compounds using chemical analysis and the FLEXPART model

    NASA Astrophysics Data System (ADS)

    Martinsson, Johan; Monteil, Guillaume; Sporre, Moa K.; Kaldal Hansen, Anne Maria; Kristensson, Adam; Eriksson Stenström, Kristina; Swietlicki, Erik; Glasius, Marianne

    2017-09-01

    Molecular tracers in secondary organic aerosols (SOAs) can provide information on origin of SOA, as well as regional scale processes involved in their formation. In this study 9 carboxylic acids, 11 organosulfates (OSs) and 2 nitrooxy organosulfates (NOSs) were determined in daily aerosol particle filter samples from Vavihill measurement station in southern Sweden during June and July 2012. Several of the observed compounds are photo-oxidation products from biogenic volatile organic compounds (BVOCs). Highest average mass concentrations were observed for carboxylic acids derived from fatty acids and monoterpenes (12. 3 ± 15. 6 and 13. 8 ± 11. 6 ng m-3, respectively). The FLEXPART model was used to link nine specific surface types to single measured compounds. It was found that the surface category sea and ocean was dominating the air mass exposure (56 %) but contributed to low mass concentration of observed chemical compounds. A principal component (PC) analysis identified four components, where the one with highest explanatory power (49 %) displayed clear impact of coniferous forest on measured mass concentration of a majority of the compounds. The three remaining PCs were more difficult to interpret, although azelaic, suberic, and pimelic acid were closely related to each other but not to any clear surface category. Hence, future studies should aim to deduce the biogenic sources and surface category of these compounds. This study bridges micro-level chemical speciation to air mass surface exposure at the macro level.

  14. Photodecomposition of volatile organic compounds using TiO2 nanoparticles.

    PubMed

    Jwo, Ching-Song; Chang, Ho; Kao, Mu-Jnug; Lin, Chi-Hsiang

    2007-06-01

    This study examined the photodecomposition of volatile organic compounds (VOCs) using TiO2 catalyst fabricated by the Submerged Arc Nanoparticle Synthesis System (SANSS). TiO2 catalyst was employed to decompose volatile organic compounds and compare with Degussa-P25 TiO2 in terms of decomposition efficiency. In the electric discharge manufacturing process, a Ti bar, applied as the electrode, was melted and vaporized under high temperature. The vaporized Ti powders were then rapidly quenched under low-temperature and low-pressure conditions in deionized water, thus nucleating and forming nanocrystalline powders uniformly dispersed in the base solvent. The average diameter of the TiO2 nanoparticles was 20 nm. X-ray diffraction analysis confirmed that the nanoparticles in the deionized water were Anatase type TiO2. It was found that gaseous toluene exposed to UV irradiation produced intermediates that were even harder to decompose. After 60-min photocomposition, Degussa-P25 TiO2 reduced the concentration of gaseous toluene to 8.18% while the concentration after decomposition by SANSS TiO2 catalyst dropped to 0.35%. Under UV irradiation at 253.7 +/- 184.9 nm, TiO2 prepared by SANSS can produce strong chemical debonding energy, thus showing great efficiency, superior to that of Degussa-P25 TiO2, in decomposing gaseous toluene and its intermediates.

  15. Analysis of organic volatile flavor compounds in fermented stinky tofu using SPME with different fiber coatings.

    PubMed

    Liu, Yuping; Miao, Zhiwei; Guan, Wei; Sun, Baoguo

    2012-03-26

    The organic volatile flavor compounds in fermented stinky tofu (FST) were studied using SPME-GC/MS. A total of 39 volatile compounds were identified, including nine esters, seven alcohols, five alkenes, four sulfides, three heterocycles, three carboxylic acids, three ketones, two aldehydes, one phenol, one amine and one ether. These compounds were determined by MS, and conformed by comparison of the retention times of the separated constituents with those of authentic samples and by comparison of retention indexes (RIs) of separated constituents with the RIs reported in the literature. The predominant volatile compound in FST was indole, followed by dimethyl trisulfide, phenol, dimethyl disulfide and dimethyl tetrasulfide. In order to find a better extraction time, the extraction times was optimized for each type of SPME fiber; the results show that the best extraction time for Carboxen/PDMS is 60 min, for PDMS/DVB 30 min, for DVB/CAR/PDMS 60 min and for PDMS 75 min. Of the four fibers used in this work, Carboxen/PDMS is found to be the most suitable to extract the organic volatile flavor compounds in fermented stinky tofu.

  16. Sensitivity of Aerosol Mass and Microphysics to varying treatments of Condensational Growth of Secondary Organic Compounds in a regional model

    NASA Astrophysics Data System (ADS)

    Lowe, Douglas; Topping, David; McFiggans, Gordon

    2017-04-01

    Gas to particle partitioning of atmospheric compounds occurs through disequilibrium mass transfer rather than through instantaneous equilibrium. However, it is common to treat only the inorganic compounds as partitioning dynamically whilst organic compounds, represented by the Volatility Basis Set (VBS), are partitioned instantaneously. In this study we implement a more realistic dynamic partitioning of organic compounds in a regional framework and assess impact on aerosol mass and microphysics. It is also common to assume condensed phase water is only associated with inorganic components. We thus also assess sensitivity to assuming all organics are hygroscopic according to their prescribed molecular weight. For this study we use WRF-Chem v3.4.1, focusing on anthropogenic dominated North-Western Europe. Gas-phase chemistry is represented using CBM-Z whilst aerosol dynamics are simulated using the 8-section MOSAIC scheme, including a 9-bin VBS treatment of organic aerosol. Results indicate that predicted mass loadings can vary significantly. Without gas phase ageing of higher volatility compounds, dynamic partitioning always results in lower mass loadings downwind of emission sources. The inclusion of condensed phase water in both partitioning models increases the predicted PM mass, resulting from a larger contribution from higher volatility organics, if present. If gas phase ageing of VBS compounds is allowed to occur in a dynamic model, this can often lead to higher predicted mass loadings, contrary to expected behaviour from a simple non-reactive gas phase box model. As descriptions of aerosol phase processes improve within regional models, the baseline descriptions of partitioning should retain the ability to treat dynamic partitioning of organics compounds. Using our simulations, we discuss whether derived sensitivities to aerosol processes in existing models may be inherently biased. This work was supported by the Natural Environment Research Council within

  17. Cytotoxic Compounds from Aerial Organs of Xanthium strumarium.

    PubMed

    Ferrer, Janet Piloto; Zampini, Iris Catiana; Cuello, Ana Soledad; Francisco, Marbelis; Romero, Aylema; Valdivia, Dayana; Gonzalez, Maria; Carlos Salas; Lamar, Angel Sanchez; Isla, Maria Inés

    2016-03-01

    Xanthium strumarium L., the main species of the genus Xanthium, is ubiquitously distributed. The aim of this study was to determine the cytotoxic effect of aerial organs of X strumarium, grown in Cuba, against cancer cell lines and the isolation of compounds potentially responsible for this activity. Initially, an ethanol partitioning procedure yielded the XSE extract that was subsequently fractionated with chloroform resulting in a XSCF fraction. Both, XSE and XSCF fractions exhibited cytotoxic effects on MDA MB-23 1, MCF7, A549 and CT26 cell lines by using the MTT assay. Above all, the XSCF fraction was more active than XSE. For this reason, XSCF was subsequently fractionated by silica gel chromatography and the active fractions submitted to semi-preparative HPLC for isolation of bioactive compounds. Six sub-fractions (SF1 to SF6) were recovered. Sub-fractions 3 and 6 were the most active on each assayed cell line, while sub-fractions 4 and 5 were only active against A549 and CT26 cell lines. In each case, sub-fraction 6 showed the strongest inhibitory effect. The HPLC-DAD fingerprint of sub-fraction 6 showed a single peak that was identified by GC-MS as (-) spathulenol, a sesquiterpene with reported antitumor activity.

  18. How does predation affect the bioaccumulation of hydrophobic organic compounds in aquatic organisms?

    PubMed

    Xia, Xinghui; Li, Husheng; Yang, Zhifeng; Zhang, Xiaotian; Wang, Haotian

    2015-04-21

    It is well-known that the body burden of hydrophobic organic compounds (HOCs) increases with the trophic level of aquatic organisms. However, the mechanism of HOC biomagnification is not fully understood. To fill this gap, this study investigated the effect of predation on the bioaccumulation of polycyclic aromatic hydrocarbons (PAHs), one type of HOC, in low-to-high aquatic trophic levels under constant freely dissolved PAH concentrations (1, 5, or 10 μg L(-1)) maintained by passive dosing systems. The tested PAHs included phenanthrene, anthracene, fluoranthene, and pyrene. The test organisms included zebrafish, which prey on Daphnia magna, and cichlids, which prey on zebrafish. The results revealed that for both zebrafish and cichlids, predation elevated the uptake and elimination rates of PAHs. The increase of uptake rate constant ranged from 20.8% to 39.4% in zebrafish with the amount of predation of 5 daphnids per fish per day, and the PAH uptake rate constant increased with the amount of predation. However, predation did not change the final bioaccumulation equilibrium; the equilibrium concentrations of PAHs in fish only depended on the freely dissolved concentration in water. Furthermore, the lipid-normalized water-based bioaccumulation factor of each PAH was constant for fish at different trophic levels. These findings infer that the final bioaccumulation equilibrium of PAHs is related to a partition between water and lipids in aquatic organisms, and predation between trophic levels does not change bioaccumulation equilibrium but bioaccumulation kinetics at stable freely dissolved PAH concentrations. This study suggests that if HOCs have not reached bioaccumulation equilibrium, biomagnification occurs due to enhanced uptake rates caused by predation in addition to higher lipid contents in higher trophic organisms. Otherwise, it is only due to the higher lipid contents in higher trophic organisms.

  19. Hazardous organic compounds in groundwater near Tehran automobile industry.

    PubMed

    Dobaradaran, Sina; Mahvi, Amir Hossein; Nabizadeh, Ramin; Mesdaghinia, Alireza; Naddafi, Kazem; Yunesian, Masoud; Rastkari, Noushin; Nazmara, Shahrokh

    2010-11-01

    Potential of groundwater contamination by trichloroethylene (TCE) and other volatile organic compounds VOCs near car industry was conducted in this study. TCE, PCE, toluene, xylene, dichloromethane, cyclohexane, n-hexane and n-pentane were detected in all groundwaters. Mean TCE levels in groundwater ranged from 124.37 to 1,035.9 μg L⁻¹ with maximum level of 1,345.7 μg L⁻¹. Due to the data obtained from conventional wastewater treatment in car factory the TCE removal efficiency was only 24 percent which necessitates the TCE removal by advanced treatment processes before the use of well water.

  20. Allelochemical effects of volatile compounds and organic extracts from Muscodor yucatanensis, a tropical endophytic fungus from Bursera simaruba.

    PubMed

    Macías-Rubalcava, Martha L; Hernández-Bautista, Blanca E; Oropeza, Fabiola; Duarte, Georgina; González, María C; Glenn, Anthony E; Hanlin, Richard T; Anaya, Ana Luisa

    2010-10-01

    Muscodor yucatanensis, an endophytic fungus, was isolated from the leaves of Bursera simaruba (Burseraceae) in a dry, semideciduous tropical forest in the Ecological Reserve El Eden, Quintana Roo, Mexico. We tested the mixture of volatile organic compounds (VOCs) produced by M. yucatanensis for allelochemical effects against other endophytic fungi, phytopathogenic fungi and fungoids, and plants. VOCs were lethal to Guignardia mangifera, Colletotrichum sp., Phomopsis sp., Alternaria solani, Rhizoctonia sp., Phytophthora capsici, and P. parasitica, but had no effect on Fusarium oxysporum, Xylaria sp., the endophytic isolate 120, or M. yucatanensis. VOCs inhibited root elongation in amaranth, tomato, and barnyard grass, particularly those produced during the first 15 days of fungal growth. VOCs were identified by gas chromatography/mass spectrometry and included compounds not previously reported from other Muscodor species and the previously reported compounds octane, 2-methyl butyl acetate, 2-pentyl furan, caryophyllene, and aromadendrene. We also evaluated organic extracts from the culture medium and mycelium of M. yucatanensis on the same endophytes, phytopathogens, and plants. In general, extracts inhibited plants more than endophytic or phytopathogens fungi. G. mangifera was the only organism that was significantly stimulated by both extracts regardless of concentration. Compounds in both organic extracts were identified by gas chromatography/mass spectrometry. We discuss the possible allelopathic role that metabolites of M. yucatanensis play in its ecological interactions with its host plant and other organisms.