WorldWideScience

Sample records for hydrocarbon chc solvents

  1. Miscellaneous hydrocarbon solvents.

    Science.gov (United States)

    Bebarta, Vikhyat; DeWitt, Christopher

    2004-08-01

    The solvents discussed in this article are common solvents not categorized as halogenated, aromatic, or botanical. The solvents discussed are categorized into two groups: hydrocarbon mixtures and single agents. The hydrocarbon mixtures discussed are Stoddard solvent, naphtha, and kerosene. The remaining solvents described are n-hexane, methyl n-butyl ketone, dimethylformamide, dimethyl sulfoxide, and butyl mercaptans. Effects common to this group of agents and their unique effects are characterized. Treatment of exposures and toxic effects of these solvents is described, and physiochemical properties and occupational exposure levels are listed.

  2. 27 CFR 21.125 - Rubber hydrocarbon solvent.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Rubber hydrocarbon solvent. 21.125 Section 21.125 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU....125 Rubber hydrocarbon solvent. (a) Rubber hydrocarbon solvent is a petroleum derivative....

  3. Chlorinated hydrocarbons- (CHC) and PCDD/F-levels in sediments and breams (Abramis brama) from the river Elbe (contribution to the German Environmental Specimen Banking)

    Energy Technology Data Exchange (ETDEWEB)

    Oxynos, K. [GSF-Forschungszentrum fuer Umwelt und Gesundheit, Institut fuer Oekologische Chemie, Oberschleissheim (Germany); Schramm, K.W. [GSF-Forschungszentrum fuer Umwelt und Gesundheit, Institut fuer Oekologische Chemie, Oberschleissheim (Germany); Marth, P. [GSF-Forschungszentrum fuer Umwelt und Gesundheit, Institut fuer Oekologische Chemie, Oberschleissheim (Germany); Schmitzer, J. [GSF-Forschungszentrum fuer Umwelt und Gesundheit, Institut fuer Oekologische Chemie, Oberschleissheim (Germany); Kettrup, A. [GSF-Forschungszentrum fuer Umwelt und Gesundheit, Institut fuer Oekologische Chemie, Oberschleissheim (Germany)

    1995-09-01

    Chlorinated hydrocarbons have been determined in sediments and breams (Abramis brama) from different locations along the river Elbe, starting from the border to the Czech Republic down-stream up to Cumlosen (river km 470), near the frontier of the former German Democratic Republic. High levels of hexachlorobenzene (HCB) have been found in sediments. HCB, DDT-metabolites and octachlorostyrene (OCS) have been the most dominant compounds in bream, especially fish from eastern sampling sites have been heavily contaminated. Furthermore, sediments from 1991-1993 have been analysed to determine polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F). The CHC-burden of the river Elbe declines downstream, whereas the PCDD/F-content increases in that direction. (orig.)

  4. 40 CFR Table 2b to Subpart E of... - Reactivity Factors for Aliphatic Hydrocarbon Solvent Mixtures

    Science.gov (United States)

    2010-07-01

    ... Hydrocarbon Solvent Mixtures 2B Table 2B to Subpart E of Part 59 Protection of Environment ENVIRONMENTAL... Hydrocarbon Solvent Mixtures Bin Averageboiling point * (degrees F) Criteria Reactivityfactor 1 80-205 Alkanes... + Dry Point) / 2 (b) Aromatic Hydrocarbon Solvents...

  5. Highly Efficient and Reproducible Nonfullerene Solar Cells from Hydrocarbon Solvents

    KAUST Repository

    Wadsworth, Andrew

    2017-06-01

    With chlorinated solvents unlikely to be permitted for use in solution-processed organic solar cells in industry, there must be a focus on developing nonchlorinated solvent systems. Here we report high-efficiency devices utilizing a low-bandgap donor polymer (PffBT4T-2DT) and a nonfullerene acceptor (EH-IDTBR) from hydrocarbon solvents and without using additives. When mesitylene was used as the solvent, rather than chlorobenzene, an improved power conversion efficiency (11.1%) was achieved without the need for pre- or post-treatments. Despite altering the processing conditions to environmentally friendly solvents and room-temperature coating, grazing incident X-ray measurements confirmed that active layers processed from hydrocarbon solvents retained the robust nanomorphology obtained with hot-processed chlorinated solvents. The main advantages of hydrocarbon solvent-processed devices, besides the improved efficiencies, were the reproducibility and storage lifetime of devices. Mesitylene devices showed better reproducibility and shelf life up to 4000 h with PCE dropping by only 8% of its initial value.

  6. Extraction of hydrocarbons from microalga Botryococcus braunii with switchable solvents.

    Science.gov (United States)

    Samorì, Chiara; Torri, Cristian; Samorì, Giulia; Fabbri, Daniele; Galletti, Paola; Guerrini, Franca; Pistocchi, Rossella; Tagliavini, Emilio

    2010-05-01

    Lipid extraction is a critical step in the development of biofuels from microalgae. Here a new procedure was proposed to extract hydrocarbons from dried and water-suspended samples of the microalga Botryococcus braunii by using switchable-polarity solvents (SPS) based on 1,8-diazabicyclo-[5.4.0]-undec-7-ene (DBU) and an alcohol. The high affinity of the non-ionic form of DBU/alcohol SPS towards non-polar compounds was exploited to extract hydrocarbons from algae, while the ionic character of the DBU-alkyl carbonate form, obtained by the addition of CO(2), was used to recover hydrocarbons from the SPS. DBU/octanol and DBU/ethanol SPS were tested for the extraction efficiency of lipids from freeze-dried B. braunii samples and compared with n-hexane and chloroform/methanol. The DBU/octanol system was further evaluated for the extraction of hydrocarbons directly from algal culture samples. DBU/octanol exhibited the highest yields of extracted hydrocarbons from both freeze-dried and liquid algal samples (16% and 8.2% respectively against 7.8% and 5.6% with n-hexane).

  7. 40 CFR Table 2c to Subpart E of... - Reactivity Factors for Aromatic Hydrocarbon Solvent Mixtures

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Reactivity Factors for Aromatic Hydrocarbon Solvent Mixtures 2C Table 2C to Subpart E of Part 59 Protection of Environment ENVIRONMENTAL... Hydrocarbon Solvent Mixtures Bin Boiling range (degrees F) Criteria Reactivityfactor 21 280-290...

  8. GREEN CATALYZED OXIDATION OF HYDROCARBONS IN ALTERNATIVE SOLVENT SYSTEMS GENERATED BY PARIS II

    Science.gov (United States)

    Green Catalyzed Oxidation of Hydrocarbons in Alternative Solvent Systems Generated by PARIS IIMichael A. Gonzalez*, Thomas M. Becker, and Paul F. Harten; Sustainable Technology Division, Office of Research and Development; United States Environmental Protection Agency, 26...

  9. Dicty_cDB: CHC251 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CH (Link to library) CHC251 (Link to dictyBase) - - - Contig-U16381-1 - (Link to Original site) CHC2...51F 150 - - - - - - Show CHC251 Library CH (Link to library) Clone ID CHC251 (Link to dicty...iol.tsukuba.ac.jp/CSM/CH/CHC2-C/CHC251Q.Seq.d/ Representative seq. ID - (Link to ...Original site) Representative DNA sequence >CHC251 (CHC251Q) /CSM/CH/CHC2-C/CHC251Q.Seq.d/ CTGTTGGCCTACTGGTA...d/ 186 6e-47 CHC476 (CHC476Q) /CSM/CH/CHC4-D/CHC476Q.Seq.d/ 186 6e-47 CHC251 (CHC251Q) /CSM/CH/CHC2-C/CHC251Q.Seq.d/ 186 6e-47 CHC2

  10. Phase Behavior of Light Gases in Hydrocarbon and Aqueous Solvents

    Energy Technology Data Exchange (ETDEWEB)

    Gasem, K.A.M.; Robinson, R.L., Jr.; Trvedi, N.J., Gao, W.

    1997-09-01

    Under previous support from the Department of Energy, an experimental facility has been established and operated to measure valuable vapor-liquid equilibrium data for systems of interest in the production and processing of coal fluids. To facilitate the development and testing of models for prediction of the phase behavior for such systems, we have acquired substantial amounts of data on the equilibrium phase compositions for binary mixtures of heavy hydrocarbon solvents with a variety of supercritical solutes, including hydrogen, methane, ethane, carbon monoxide, and carbon dioxide. The present project focuses on measuring the phase behavior of light gases and water in Fischer-Tropsch (F-T) type solvents at conditions encountered in indirect liquefaction processes and evaluating and developing theoretically-based correlating frameworks to predict the phase behavior of such systems. Specific goals of the proposed work include (a) developing a state-of-the-art experimental facility to permit highly accurate measurements of equilibrium phase compositions (solubilities) of challenging F-T systems, (b) measuring these properties for systematically-selected binary, ternary and molten F-T wax mixtures to provide critically needed input data for correlation development, (c) developing and testing models suitable for describing the phase behavior of such mixtures, and (d) presenting the modeling results in generalized, practical formats suitable for use in process engineering calculations. During the present reporting period, our solubility apparatus was refurbished and restored to full service. To test the experimental apparatus and procedures used, measurements were obtained for the solubility Of C0{sub 2} in benzene at 160{degrees}F. Having confirmed the accuracy of the newly acquired data in comparison with our previous measurements and data reported in the literature for this test system, we have begun to measure the solubility of hydrogen in hexane. The measurements

  11. Dicty_cDB: CHC270 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CH (Link to library) CHC270 (Link to dictyBase) - - - Contig-U11649-1 CHC270P (Link to Original site) CHC2...70F 433 CHC270Z 724 CHC270P 1137 - - Show CHC270 Library CH (Link to library) Clone ID CHC2...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/CH/CHC2-C/CHC270Q.Seq.d/ Representative seq. ID CHC2...70P (Link to Original site) Representative DNA sequence >CHC270 (CHC270Q) /CSM/CH/CHC2-C/CHC2...-cDNA Score E Sequences producing significant alignments: (bits) Value CHC270 (CHC270Q) /CSM/CH/CHC2-C/CHC27

  12. Extraction of polycyclic aromatic hydrocarbons from soot and sediment : solvent selection and implications for sorption mechanism

    NARCIS (Netherlands)

    Jonker, M.T.O.; Koelmans, A.A.

    2002-01-01

    Soot contains high levels of toxic compounds such as polycyclic aromatic hydrocarbons (PAHs). Extraction of PAHs from soot for quantitative analysis is difficult because the compounds are extremely tightly bound to the sorbent matrix. This study was designed to investigate the effect of solvent type

  13. GREEN CATALYZED OXIDATION OF HYDROCARBONS IN ALTERNATIVE SOLVENT SYSTEMS GENERATED BY PARIS II DECHEMA; GREEN SOLVENTS FOR CATALYSIS - ENVIRONMENTALLY BENIGN REACTION MEDIA

    Science.gov (United States)

    Green catalyzed oxidation of hydrocarbons in alternative solvent systems generated by PARIS IIThomas M. Becker, Michael A. Gonzalez, Paul F. Harten; Sustainable Technology Division, Office of Research and Development; United States Environmental Protection Agency, 26 West Mar...

  14. Dicty_cDB: CHC222 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available CH (Link to library) CHC222 (Link to dictyBase) - - - Contig-U16381-1 - (Link to Original site) CHC2...22F 152 - - - - - - Show CHC222 Library CH (Link to library) Clone ID CHC222 (Link to dicty...iol.tsukuba.ac.jp/CSM/CH/CHC2-A/CHC222Q.Seq.d/ Representative seq. ID - (Link to ...Original site) Representative DNA sequence >CHC222 (CHC222Q) /CSM/CH/CHC2-A/CHC222Q.Seq.d/ CACTGTTGGCCTACTGG...NA Score E Sequences producing significant alignments: (bits) Value CHC222 (CHC222Q) /CSM/CH/CHC2-A/CHC222Q.

  15. Extraction of polycyclic aromatic hydrocarbons from soot and sediment: solvent evaluation and implications for sorption mechanism.

    Science.gov (United States)

    Jonker, Michiel T O; Koelmans, Albert A

    2002-10-01

    Soot contains high levels of toxic compounds such as polycyclic aromatic hydrocarbons (PAHs). Extraction of PAHs from soot for quantitative analysis is difficult because the compounds are extremely tightly bound to the sorbent matrix. This study was designed to investigate the effect of solvent type on PAH extraction yield, to identify the most optimal solvent for PAH extraction from soot, and to gain insight into the mechanism of PAH sorption to soot in aquatic environments. To that end, different types of soot as well as coal, charcoal, and sediments containing soot-like material were extracted with seven organic solvents. Large differences in extraction recoveries were observed among solvents, with relative values as low as 16% as compared to the best extracting solvent. These differences were much larger for soot than for sediments. Dichloromethane, which to date is the most widely used solvent for soot and sediment extractions, appeared to be the overall worst extractant, whereas toluene/methanol (1:6) gave the best results. Based on extraction yields and solvent properties, extraction of PAHs from soot was explained by a two-step mechanism involving swelling of the sorbent matrix and subsequent displacement of sorbates by solvent molecules. Due to the low displacement capacity of water, desorption of PAHs from soot in the aquatic environment will be strongly limited. Moreover, a certain fraction of the total PAH mass on soot is suggested to be physically entrapped, making it unavailable for partitioning to the aqueous phase.

  16. Methanogenic biodegradation of paraffinic solvent hydrocarbons in two different oil sands tailings.

    Science.gov (United States)

    Mohamad Shahimin, Mohd Faidz; Siddique, Tariq

    2017-04-01

    Microbial communities drive many biogeochemical processes in oil sands tailings and cause greenhouse gas emissions from tailings ponds. Paraffinic solvent (primarily C5-C6; n- and iso-alkanes) is used by some oil sands companies to aid bitumen extraction from oil sands ores. Residues of unrecovered solvent escape to tailings ponds during tailings deposition and sustain microbial metabolism. To investigate biodegradation of hydrocarbons in paraffinic solvent, mature fine tailings (MFT) collected from Albian and CNRL ponds were amended with paraffinic solvent at ~0.1wt% (final concentration: ~1000mgL(-1)) and incubated under methanogenic conditions for ~1600d. Albian and CNRL MFTs exhibited ~400 and ~800d lag phases, respectively after which n-alkanes (n-pentane and n-hexane) in the solvent were preferentially metabolized to methane over iso-alkanes in both MFTs. Among iso-alkanes, only 2-methylpentane was completely biodegraded whereas 2-methylbutane and 3-methylpentane were partially biodegraded probably through cometabolism. 16S rRNA gene pyrosequencing showed dominance of Anaerolineaceae and Methanosaetaceae in Albian MFT and Peptococcaceae and co-domination of "Candidatus Methanoregula" and Methanosaetaceae in CNRL MFT bacterial and archaeal communities, respectively, during active biodegradation of paraffinic solvent. The results are important for developing future strategies for tailings reclamation and management of greenhouse gas emissions.

  17. Solvent effects on extraction of polycyclic aromatic hydrocarbons in ambient aerosol samples

    Directory of Open Access Journals (Sweden)

    Flasch Mira

    2016-01-01

    Full Text Available Polycyclic Aromatic Hydrocarbons (PAHs in the ambient particulate matter pose one of the most important issues in the focus of environmental management. The concentration of their representative, Benzo(apyrene (BaP, undergoes limitations according to European Union directive. However, a successful control over the pollution levels and their sources is limited by the high uncertainty of analytical and statistical approaches used for their characterization. Here we compare differences in PAH concentrations related to the use of different solvents in the course of ultrasonic extraction of a certified reference material (PM10-like PAH mixture and filter samples of ambient particulate matter collected in Austria for the CG-MS PAH analysis. Using solvents of increasing polarity: Cyclohexane (0,006, Toluene (0,099, Dichloromethane (0,309, Acetone (0,43 and Acetonitrile (0,460, as well as mixtures of those, filters representing high and low concentrations of particulate matter were investigated. Although some scatter of the obtained concentrations was observed no trend related to the polarity of the solvent became visible. Regarding the reproducibility, which can be expected of PAH analysis no significant difference between the different solvents was determined. This result is valid for all compounds under investigation.

  18. Influence of soil and hydrocarbon properties on the solvent extraction of high-concentration weathered petroleum from contaminated soils.

    Science.gov (United States)

    Sui, Hong; Hua, Zhengtao; Li, Xingang; Li, Hong; Wu, Guozhong

    2014-05-01

    Petroleum ether was used to extract petroleum hydrocarbons from soils collected from six oil fields with different history of exploratory and contamination. It was capable of fast removing 76-94 % of the total petroleum hydrocarbons including 25 alkanes (C11-C35) and 16 US EPA priority polycyclic aromatic hydrocarbons from soils at room temperature. The partial least squares analysis indicated that the solvent extraction efficiencies were positively correlated with soil organic matter, cation exchange capacity, moisture, pH, and sand content of soils, while negative effects were observed in the properties reflecting the molecular size (e.g., molecular weight and number of carbon atoms) and hydrophobicity (e.g., water solubility, octanol-water partition coefficient, soil organic carbon partition coefficient) of hydrocarbons. The high concentration of weathered crude oil at the order of 10(5) mg kg(-1) in this study was demonstrated adverse for solvent extraction by providing an obvious nonaqueous phase liquid phase for hydrocarbon sinking and increasing the sequestration of soluble hydrocarbons in the insoluble oil fractions during weathering. A full picture of the mass distribution and transport mechanism of petroleum contaminants in soils will ultimately require a variety of studies to gain insights into the dynamic interactions between environmental indicator hydrocarbons and their host oil matrix.

  19. Solvent

    OpenAIRE

    Hamida Y. Mostafa; Ebaa A. El-Shamy; Amal S. Farag; Nadia G. Kandile

    2013-01-01

    Neat ethylacetoacetate (EAA) and its mixtures with a co-solvent and an anti-solvent have been studied for refining of heavy wax distillate fraction to produce substantially non-carcinogenic base oil. The co-solvent and anti-solvent used are dipropylene glycol (DPG) and ethylene glycol (EG) respectively. The solubility characteristics of the main solvent and its mixed solvent systems were studied. Selection of the optimum solvent mixture and extraction variables has been studied. The effect of...

  20. Model studies for evaluating the acute neurobehavioral effects of complex hydrocarbon solvents. I. Validation of methods with ethanol

    NARCIS (Netherlands)

    McKee, R.H.; Lammers, J.H.C.M.; Hoogendijk, E.M.G.; Emmen, H.H.; Muijser, H.; Barsotti, D.A.; Owen, D.E.; Kulig, B.M.

    2006-01-01

    As a preliminary step to evaluating the acute neurobehavioral effects of hydrocarbon solvents and to establish a working model for extrapolating animal test data to humans, joint neurobehavioral/toxicokinetic studies were conducted which involved administering ethanol to rats and volunteers. The spe

  1. Dicty_cDB: CHC836 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ucing significant alignments: (bits) Value CHC836 (CHC836Q) /CSM/CH/CHC8-B/CHC836Q.Seq.d/ 170 3e-42 SFF285 (...te 2009. 4. 4 Homology vs DNA Score E Sequences producing significant alignments: (bits) Value...ificant alignments: (bits) Value U61987_1( U61987 |pid:none) Dictyostelium discoideum phosphoprotei... 37 0.

  2. Microbial diversity in a hydrocarbon- and chlorinated-solvent- contaminated aquifer undergoing intrinsic bioremediation

    Science.gov (United States)

    Dojka, M.A.; Hugenholtz, P.; Haack, S.K.; Pace, N.R.

    1998-01-01

    A culture-independent molecular phylogenetic approach was used to survey constituents of microbial communities associated with an aquifer contaminated with hydrocarbons (mainly jet fuel) and chlorinated solvents undergoing intrinsic bioremediation. Samples were obtained from three redox zones: methanogenic, methanogenic-sulfate reducing, and iron or sulfate reducing. Small-subunit rRNA genes were amplified directly from aquifer material DNA by PCR with universally conserved or Bacteria- or Archaea-specific primers and were cloned. A total of 812 clones were screened by restriction fragment length polymorphisms (RFLP), approximately 50% of which were unique. All RFLP types that occurred more than once in the libraries, as well as many of the unique types, were sequenced. A total of 104 (94 bacterial and 10 archaeal) sequence types were determined. Of the 94 bacterial sequence types, 10 have no phylogenetic association with known taxonomic divisions and are phylogenetically grouped in six novel division level groups (candidate divisions WS1 to WS6); 21 belong to four recently described candidate divisions with no cultivated representatives (OPS, OP8, OP10, and OP11); and 63 are phylogenetically associated with 10 well-recognized divisions. The physiology of two particularly abundant sequence types obtained from the methanogenic zone could be inferred from their phylogenetic association with groups of microorganisms with a consistent phenotype. One of these sequence types is associated with the genus Syntrophus; Syntrophus spp. produce energy from the anaerobic oxidation of organic acids, with the production of acetate and hydrogen. The organism represented by the other sequence type is closely related to Methanosaeta spp., which are known to be capable of energy generation only through aceticlastic methanogenesis. We hypothesize, therefore, that the terminal step of hydrocarbon degradation in the methanogenic zone of the aquifer is aceticlastic methanogenesis and

  3. The doping effect of fluorinated aromatic hydrocarbon solvents on the performance of common olefin metathesis catalysts: application in the preparation of biologically active compounds.

    Science.gov (United States)

    Samojłowicz, Cezary; Bieniek, Michał; Zarecki, Andrzej; Kadyrov, Renat; Grela, Karol

    2008-12-21

    Aromatic fluorinated hydrocarbons, used as solvents for olefin metathesis reactions, catalysed by standard commercially available Ru precatalysts, allow substantially higher yields to be obtained, especially of challenging substrates, including natural and biologically active compounds.

  4. Solvent-extractable polycyclic aromatic hydrocarbons in biochar: influence of pyrolysis temperature and feedstock.

    Science.gov (United States)

    Keiluweit, Marco; Kleber, Markus; Sparrow, Margaret A; Simoneit, Bernd R T; Prahl, Fredrick G

    2012-09-01

    Despite the increasing agricultural use of biochar as a way of combining the utilization of biomass for energy production with the removal of CO(2) from the atmosphere, it is not known how variations in pyrolysis temperature and feedstock type affect concentration and composition of polycyclic aromatic hydrocarbons (PAHs) that inevitably form and associate with biochar. To close this knowledge gap, we quantified 11 unsubstituted three- to five-ring PAHs as well as alkylated forms of phenanthrene and anthracene in grass and wood chars produced in 100 °C increments across a temperature range (100 to 700 °C). Our results show that solvent-extractable PAH concentrations in biochars produced at heat treatment temperatures (HTTs) of 400 and 500 °C greatly exceed those observed at higher and lower temperature, supporting a low HTT solid-phase formation mechanism operable at temperatures commonly used for industrial biochar production. The maximum extractable yield of 'pyrolytic' unsubstituted PAHs for grass (22 μg g(-1) at HTT = 500 °C) greatly exceeds the value for wood (5.9 μg g(-1)). Moreover, PAH signatures (e.g., total monomethylphenanthrene to phenanthrene ratios, MP/P ~2-3) at intermediate temperatures (400 °C) resemble those of fossil oils rather than that commonly attributed to pyrolytic products. Further research is needed to characterize the PAH evolution in modern pyrolysis reactors and assess the fate of biochar-bound PAHs in soils and sediments. Various commonly applied PAH ratios and indicator compounds show promise as markers for specific feedstock materials and pyrolysis conditions of biochars in environmental systems.

  5. Quantitative Analysis of Total Petroleum Hydrocarbons in Soils: Comparison between Reflectance Spectroscopy and Solvent Extraction by 3 Certified Laboratories

    Directory of Open Access Journals (Sweden)

    Guy Schwartz

    2012-01-01

    Full Text Available The commonly used analytic method for assessing total petroleum hydrocarbons (TPH in soil, EPA method 418.1, is usually based on extraction with 1,1,2-trichlorotrifluoroethane (Freon 113 and FTIR spectroscopy of the extracted solvent. This method is widely used for initial site investigation, due to the relative low price per sample. It is known that the extraction efficiency varies depending on the extracting solvent and other sample properties. This study’s main goal was to evaluate reflectance spectroscopy as a tool for TPH assessment, as compared with three commercial certified laboratories using traditional methods. Large variations were found between the results of the three commercial laboratories, both internally (average deviation up to 20%, and between laboratories (average deviation up to 103%. Reflectance spectroscopy method was found be as good as the commercial laboratories in terms of accuracy and could be a viable field-screening tool that is rapid, environmental friendly, and cost effective.

  6. Investigation of ethyl lactate as a green solvent for desorption of total petroleum hydrocarbons (TPH) from contaminated soil.

    Science.gov (United States)

    Jalilian Ahmadkalaei, Seyedeh Pegah; Gan, Suyin; Ng, Hoon Kiat; Abdul Talib, Suhaimi

    2016-11-01

    Treatment of oil-contaminated soil is a major environmental concern worldwide. The aim of this study is to examine the applicability of a green solvent, ethyl lactate (EL), in desorption of diesel aliphatic fraction within total petroleum hydrocarbons (TPH) in contaminated soil and to determine the associated desorption kinetics. Batch desorption experiments were carried out on artificially contaminated soil at different EL solvent percentages (%). In analysing the diesel range of TPH, TPH was divided into three fractions and the effect of solvent extraction on each fraction was examined. The experimental results demonstrated that EL has a high and fast desorbing power. Pseudo-second order rate equation described the experimental desorption kinetics data well with correlation coefficient values, R (2), between 0.9219 and 0.9999. The effects of EL percentage, initial contamination level of soil and liquid to solid ratio (L/S (v/w)) on initial desorption rate have also been evaluated. The effective desorption performance of ethyl lactate shows its potential as a removal agent for remediation of TPH-contaminated soil worldwide.

  7. DETERMINATION OF SOLID-LIQUID EQUILIBRIA DATA FOR MIXTURES OF HEAVY HYDROCARBONS IN A LIGHT SOLVENT

    Energy Technology Data Exchange (ETDEWEB)

    F.V. Hanson; J.V. Fletcher; Karthik R.

    2003-06-01

    A methodology was developed using an FT-IR spectroscopic technique to obtain solid-liquid equilibria (SLE) data for mixtures of heavy hydrocarbons in significantly lighter hydrocarbon diluents. SLE was examined in multiple Model Oils that were assembled to simulate waxes. The various Model oils were comprised of C-30 to C-44 hydrocarbons in decane. The FT-IR technique was used to identify the wax precipitation temperature (WPT). The DSC technique was also used in the identification of the onset of the two-phase equilibrium in this work. An additional Model oil made up of C-20 to C-30 hydrocarbons in decane was studied using the DSC experiment. The weight percent solid below the WPT was calculated using the FT-IR experimental results. The WPT and the weight percent solid below the WPT were predicted using an activity coefficient based thermodynamic model. The FT-IR spectroscopy method is found to successfully provide SLE data and also has several advantages over other laboratory-based methods.

  8. Geochemical markers and polycyclic aromatic hydrocarbons in solvent extracts from diesel engine particulate matter.

    Science.gov (United States)

    Fabiańska, Monika; Kozielska, Barbara; Bielaczyc, Piotr; Woodburn, Joseph; Konieczyński, Jan

    2016-04-01

    Exhaust particulate from compression ignition (CI) engines running on engine and chassis dynamometers was studied. Particulate dichloromethane extracts were qualitatively and quantitatively analyzed for polycyclic aromatic hydrocarbons (PAHs) and biomarkers by gas chromatography with flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS). PAH group profiles were made and the PAH group shares according to the number of rings (2 or 3; 4; 5 or more) as well as diagnostic indices were calculated. Values of geochemical ratios of selected biomarkers and alkyl aromatic hydrocarbons were compared with literature values. A geochemical interpretation was carried out using these values and biomarker and alkyl aromatic hydrocarbon distributions. It has been shown that geochemical features are unequivocally connected to the emission of fossil fuels and biofuels burned in CI engines. The effect of the exothermic combustion process is limited to low-molecular-weight compounds, which shows that the applied methodology permits source identification of PAHs coexisting in the particulate emitted.

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

    Science.gov (United States)

    Kolak, Jonathan J.; Burruss, Robert A.

    2014-01-01

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

  10. Influence of Solvent-Like Sidechains on the Adsorption of Light Hydrocarbons in Metal-Organic Frameworks.

    Science.gov (United States)

    Schneemann, Andreas; Bloch, Eric D; Henke, Sebastian; Llewellyn, Philip L; Long, Jeffrey R; Fischer, Roland A

    2015-12-14

    A variety of strategies have been developed to adsorb and separate light hydrocarbons in metal-organic frameworks. Here, we present a new approach in which the pores of a framework are lined with four different C3 sidechains that feature various degrees of branching and saturation. These pendant groups, which essentially mimic a low-density solvent with restricted degrees of freedom, offer tunable control of dispersive host-guest interactions. The performance of a series of frameworks of the type Zn2 (fu-bdc)2 (dabco) (fu-bdc(2-) =functionalized 1,4-benzenedicarboxylate; dabco=1,4-diazabicyclo[2.2.2]octane), which feature a pillared layer structure, were investigated for the adsorption and separation of methane, ethane, ethylene, and acetylene. The four frameworks exhibit low methane uptake, whereas C2 hydrocarbon uptake is substantially higher as a result of the enhanced interaction of these molecules with the ligand sidechains. Most significantly, the adsorption quantities and selectivity were found to depend strongly upon the type of sidechains attached to the framework scaffold.

  11. Extraction of lignite coal fly ash for polynuclear aromatic hydrocarbons: modified and unmodified supercritical fluid extraction, enhanced-fluidity solvents, and accelerated solvent extraction.

    Science.gov (United States)

    Kenny, D V; Olesik, S V

    1998-02-01

    A comparison among modified and unmodified supercritical fluid extraction (SFE), enhanced-fluidity liquid extraction, and accelerated solvent extraction (ASE) techniques was made for the extraction of polynuclear aromatic hydrocarbons (PAHs) from an aged, spiked lignite coal fly ash. All of the attempted extraction conditions allowed the extraction of the PAHs to some degree, but no single extraction technique proved to be superior for all of the PAHs used. Three groups of PAHs with similar extraction efficiencies were identified. The group with the lowest molecular weights was best recovered using a 90% CO2-10% methanol mixture at 70 degrees C and 238 atm. The group of medium-molecular-weight PAHs was recovered equally well using any of three extraction conditions: SFE (100% CO2, 90 degrees C, and 238 atm), enhanced-fluidity liquid mixture (60% CO2-40% methanol, 70 degrees C, and 238 atm), and a methanol ASE mixture. The group of high-molecular-weight PAHs seemed to be equally well recovered with all of the attempted extraction conditions, but the enhanced-fluidity conditions (60% CO2-40% methanol, 70 degrees C, and 238 atm) had extraction recoveries (> 85%) with the lowest standard deviations (approximately 5%).

  12. Extraction of bituminous coal fly ash for polynuclear aromatic hydrocarbons: evaluation of modified and unmodified supercritical fluid extraction, enhanced fluidity solvents, and accelerated solvent extraction.

    Science.gov (United States)

    Kenny, D V; Olesik, S V

    1998-02-01

    A comparison among supercritical fluid extraction (SFE), modified SFE, enhanced-fluidity extraction, and accelerated solvent extraction (ASE) techniques was made for the extraction of polynuclear aromatic hydrocarbons (PAHs) from an aged, spiked bituminous coal fly ash. Non-ASE extraction techniques used in this study could not recover PAHs with molecular weights greater than that of pyrene. ASE techniques using methylene chloride (with and without a static step) and toluene were able to recover most of the PAHs studied. None of the ASE techniques could quantitatively extract the low-molecular-weight PAHs from the bituminous fly ash. The medium-molecular-weight PAHs were best recovered with toluene ASE. The high-molecular-weight PAHs were best recovered with the toluene ASE technique (> 80%), but the overall precision of these measurements was low. Methylene chloride ASE with a static step recovered the high-molecular-weight PAHs with the next highest efficiency (approximately 55%) and had standard deviations less than 10% (longer extraction times [> 30 min] with the methylene chloride would increase the recoveries of these analytes.) A comparison of the results from this study with those of a previous study using lignite coal fly ash illustrates the difficulty in developing and adapting analyte-specific extraction methods for analytes that are adsorbed on different matrices.

  13. Determination of solubility parameters and thermodynamic properties in hydrocarbon-solvent systems by gas chromatography

    Directory of Open Access Journals (Sweden)

    E. Díaz

    2007-06-01

    Full Text Available Gas chromatography used to calculate the specific retention volume of several hydrocarbons in different chromatographic liquid phases (Squalane, Carbowax-400, Carbowax-1500, Carbowax-4000, Amine-220, Dinonyl phthalate, Tributyl phosphate and Trixylenyl phosphate. Some thermodynamic parameters, such as enthalpy of sorption and Flory-Huggins parameters relating the interaction between liquid phases and solutes, were also calculated from the determined retention volumes. Liquid phase solubility parameters of Squalane, Carbowax-400, Carbowax-1500 and Carbowax-4000 at 80 ºC as well as the polar and apolar components were calculated too. A new model was proposed to correlate polar contribution to the solubility parameter of a liquid phase with the specific retention volume of a solute in this liquid phase.

  14. IS CHC student surface learner A cross-cultural perspective

    Institute of Scientific and Technical Information of China (English)

    李佩绮

    2008-01-01

    In the past decades, the "CH"(Confucian Heritage Culture)learner phenomenon had aroused the interest of sociologists, educators and psychologists. Examination orientation, achievement orientation, use of repetitive learning, synthesis of memorization and understanding, and the use of recitation to bring about sharp focus for better understanding were some of the themes of these researches. This paper will explain what the general paradox of CHC learners is and how cultural difference can affect students' motivation for learning according to Chen and Stevenson's model of cultural influence, and discuss the major misconception of CHC learners' study approach.

  15. Monitoring the effect of poplar trees on petroleum-hydrocarbon and chlorinated-solvent contaminated ground water

    Science.gov (United States)

    Landmeyer, J.E.

    2001-01-01

    At contaminated groundwater sites, poplar trees can be used to affect groundwater levels, flow directions, and ultimately total groundwater and contaminant flux to areas downgradient of the trees. The magnitude of the hydrologic changes can be monitored using fundamental concepts of groundwater hydrology, in addition to plant physiology-based approaches, and can be viewed as being almost independent of the contaminant released. The affect of poplar trees on the fate of groundwater contaminants, however, is contaminant dependent. Some petroleum hydrocarbons or chlorinated solvents may be mineralized or transformed to innocuous compounds by rhizospheric bacteria associated with the tree roots, mineralized or transformed by plant tissues in the transpiration stream or leaves after uptake, or passively volatilized and rapidly dispersed or oxidized in the atmosphere. These processes also can be monitored using a combination of physiological- or geochemical-based field or laboratory approaches. When combined, such hydrologic and contaminant monitoring approaches can result in a more accurate assessment of the use of poplar trees to meet regulatory goals at contaminated groundwater sites, verify that these goals continue to be met in the future, and ultimately lead to a consensus on how the performance of plant-based remedial strategies (phytoremediation) is to be assessed.

  16. On the interpretation of the CHC factor Gc

    NARCIS (Netherlands)

    K.-J. Kan; R.A. Kievit; C. Dolan; H. van der Maas

    2011-01-01

    On the one hand, the factors Gf and Gc in the Cattell-Horn-Carroll (CHC) model of intelligence are hypothesized to represent individual differences in unique psychological or biological capacities. On the other hand, they are interpreted as representing the theoretical variables fluid and crystalliz

  17. Accelerated solvent extraction method for the quantification of polycyclic aromatic hydrocarbons in cocoa beans by gas chromatography-mass spectrometry.

    Science.gov (United States)

    Belo, Renata França Cassimiro; Figueiredo, Júlia Pereira; Nunes, Carolina Mariana; Pissinatti, Rafael; Souza, Scheilla Vitorino Carvalho de; Junqueira, Roberto Gonçalves

    2017-05-15

    An accelerated solvent extraction (ASE) procedure for use with gas chromatography-mass spectrometry (GC-MS) was optimized for the determination of eight polycyclic aromatic hydrocarbons (PAHs) in cocoa beans. Plackett-Burman and rotatable central composite design (RCCD) indicated that three variables affected the recoveries of PAHs during the extraction and purification steps: agitation time in the second liquid-liquid partition, weight of silica gel in the column, and volume of hexane for PAH elution from the column. After obtaining the optimal conditions, a single laboratory method validation was performed. Linearity was demonstrated for benzo[a]pyrene in the concentration range from 0.5 to 8.0mgkg(-1) of sample, corresponding to 1.25-20.0μgkg(-1) of cocoa on a fat basis. For the other analytes, linearity was observed from 0.75 to 8.0μgkg(-1) of sample (1.88-20.0μgkg(-1) of cocoa on a fat basis). Significant matrix effects were found for chrysene and benzo[b]fluoranthene. The precision of the method was verified with relative standard deviations (RSDs) ranging from 2.57 to 14.13% and from 4.36 to 19.77% under repeatability and intermediate precision conditions, respectively. The average recoveries of the eight PAHs ranged from 74.99 to 109.73%. These parameters, limits and measurement uncertainties met the performance criteria established by European Union regulations, except for the theoretical limit of detection for chrysene. The method was applied to the analysis of samples of Brazilian cocoa beans, and only one sample was found to have a PAH content above the maximum limit defined by the European Union legislation. This optimized and validated method is intended to be used as part of the official Brazilian monitoring programs investigating contaminants and residues in food. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. An Improved CHC Algorithm for Damage Diagnosis of Offshore Platforms

    Institute of Scientific and Technical Information of China (English)

    HUANG Weiping; WANG Xiaoyan

    2007-01-01

    An improved CHC algorithm is proposed in the paper and it could be used for the damage diagnosis of structures. It breaks the bottle neck of genetic algorithm in the damage diagnosis of large structures and takes a shorter time than the SGA (Standard Genetic Algorithm) in diagnosing structural damage with the same level of error. The case studies show that the algorithm is rapid in convergence and produces satisfactory results in diagnosing both fixed-end beams and jacket offshore platforms.

  19. Colony fusion in Argentine ants is guided by worker and queen cuticular hydrocarbon profile similarity.

    Science.gov (United States)

    Vásquez, Gissella M; Schal, Coby; Silverman, Jules

    2009-08-01

    Introduced populations of the Argentine ant, Linepithema humile, have experienced moderate to severe losses of genetic diversity, which may have affected nestmate recognition to various degrees. We hypothesized that cuticular hydrocarbons (CHC) serve as nestmate recognition cues, and facilitate colony fusion of unrelated L. humile colonies that share similar CHC profiles. In this study, we paired six southeastern U.S. L. humile colonies in a 6-month laboratory fusion assay, and determined if worker and queen CHC profile similarity between colonies was associated with colony fusion and intercolony genetic similarity. We also compared worker and queen CHC profiles between fused colony pairs and unpaired controls to determine if worker and queen chemical profiles changed after fusion. We found that colony fusion correlated with the CHC similarity of workers and queens, with the frequency of fusion increasing with greater CHC profile similarity between colonies. Worker and queen CHC profile similarity between colonies also was associated with genetic similarity between colonies. Queen CHC profiles in fused colonies appeared to be a mix of the two colony phenotypes. In contrast, when only one of the paired colonies survived, the CHC profile of the surviving queens did not diverge from that of the colony of origin. Similarly, workers in non-fused colonies maintained their colony-specific CHC, whereas in fused colonies the worker CHC profiles were intermediate between those of the two colonies. These results suggest a role for CHC in regulating interactions among mutually aggressive L. humile colonies, and demonstrate that colony fusion correlates with both genetic and CHC similarities. Further, changes in worker and queen chemical profiles in fused colonies suggest that CHC plasticity may sustain the cohesion of unrelated L. humile colonies that had fused.

  20. Indirectly suspended droplet microextraction of water-miscible organic solvents by salting-out effect for the determination of polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Daneshfar, Ali; Khezeli, Tahere

    2014-12-01

    A simple and low-cost method that indirectly suspended droplet microextraction of water-miscible organic solvents (ISDME) by salting-out effect before high-performance liquid chromatography and ultraviolet (HPLC-UV) detection was used for the determination of polycyclic aromatic hydrocarbons (PAHs) in different samples. The ISDME is a combination of salting-out extraction of water-miscible organic solvent and directly suspended droplet microextraction (DSDME). Ninety-five microliters water-miscible organic solvent (1-propanol) was added to a 500-µL sample. A homogeneous solution was formed immediately. To produce a steady vortex at the top of the solution, the sample was agitated at 700 rpm using a magnetic stirrer. By the addition of ammonium sulfate (saturated solution) to the homogeneous solution, 1-propanol was separated and collected at the bottom of the steady vortex. Finally, 20 µL 1-propanol was injected into HPLC-UV. The effects of important parameters such as water-miscible organic solvent (type and volume), type of salt, and extraction time were evaluated. Under optimum conditions, the method has a good linear calibration range (0.1 µg/L-300 µg/L), coefficients of determination (R(2) > 0.998), low limits of detection (between 0.02 µg/L and 0.27 µg/L), and acceptable recovery (>85.0%).

  1. Nanostructured alkyl carboxylic acid-based restricted access solvents: Application to the combined microextraction and cleanup of polycyclic aromatic hydrocarbons in mosses.

    Science.gov (United States)

    Caballero-Casero, N; Çabuk, H; Martínez-Sagarra, G; Devesa, J A; Rubio, S

    2015-08-26

    Alkyl carboxylic acid-based nanostructured solvents, synthesized in mixtures of tetrahydrofuran (THF) and water through self-assembly and coacervation, were proved to behave as restricted access liquids. Both physical and chemical mechanisms were found responsible for exclusion of macromolecules such as proteins and polysaccharides. The potential of these solvents for extracting small molecules from complex solid samples, without interference from large biomolecules, was here evaluated. For this purpose, they were applied to the extraction of 14 priority polycyclic aromatic hydrocarbons (PAHs) from mosses prior to their separation by liquid chromatography and fluorescence detection (LC-FLD). Sample treatment involved the vortex shaking of 200 mg of moss with 200 μL of decanoic acid-based solvent for 5 min, subsequent centrifugation for 8 min and analysis of the extract by LC-FLD using external calibration. Proteins precipitated during extraction because of both the decrease of the dielectric constant of the solution caused by THF and the formation of macromolecular complexes with decanoic acid. Polysaccharides were not solubilized in the aqueous cavities of the solvent because of their size exclusion. In-house method validation was performed according to the recommendations of the European Commission Decision 202/657/EC. Method detection and quantification limits for the different PAHs were in the ranges 0.04-0.24 and 0.14-0.80 μg kg(-1), respectively. The method was applied to the determination of different moss species collected in both polluted and unpolluted sites in the South of Spain. Recoveries were within the range 71-110%. The results obtained show that solvents with restricted access properties have the potential to expand the scope of application of restricted access materials to areas other than biological fluids because of their suitability to combine analyte isolation and sample cleanup of solid samples in a single step.

  2. The CHC22 clathrin-GLUT4 transport pathway contributes to skeletal muscle regeneration.

    Science.gov (United States)

    Hoshino, Sachiko; Sakamoto, Kazuho; Vassilopoulos, Stéphane; Camus, Stéphane M; Griffin, Christine A; Esk, Christopher; Torres, Jorge A; Ohkoshi, Norio; Ishii, Akiko; Tamaoka, Akira; Funke, Birgit H; Kucherlapati, Raju; Margeta, Marta; Rando, Thomas A; Brodsky, Frances M

    2013-01-01

    Mobilization of the GLUT4 glucose transporter from intracellular storage vesicles provides a mechanism for insulin-responsive glucose import into skeletal muscle. In humans, clathrin isoform CHC22 participates in formation of the GLUT4 storage compartment in skeletal muscle and fat. CHC22 function is limited to retrograde endosomal sorting and is restricted in its tissue expression and species distribution compared to the conserved CHC17 isoform that mediates endocytosis and several other membrane traffic pathways. Previously, we noted that CHC22 was expressed at elevated levels in regenerating rat muscle. Here we investigate whether the GLUT4 pathway in which CHC22 participates could play a role in muscle regeneration in humans and we test this possibility using CHC22-transgenic mice, which do not normally express CHC22. We observed that GLUT4 expression is elevated in parallel with that of CHC22 in regenerating skeletal muscle fibers from patients with inflammatory and other myopathies. Regenerating human myofibers displayed concurrent increases in expression of VAMP2, another regulator of GLUT4 transport. Regenerating fibers from wild-type mouse skeletal muscle injected with cardiotoxin also showed increased levels of GLUT4 and VAMP2. We previously demonstrated that transgenic mice expressing CHC22 in their muscle over-sequester GLUT4 and VAMP2 and have defective GLUT4 trafficking leading to diabetic symptoms. In this study, we find that muscle regeneration rates in CHC22 mice were delayed compared to wild-type mice, and myoblasts isolated from these mice did not proliferate in response to glucose. Additionally, CHC22-expressing mouse muscle displayed a fiber type switch from oxidative to glycolytic, similar to that observed in type 2 diabetic patients. These observations implicate the pathway for GLUT4 transport in regeneration of both human and mouse skeletal muscle, and demonstrate a role for this pathway in maintenance of muscle fiber type. Extrapolating

  3. Determining the better solvent and time for extracting soil by soxhlet in TPH (Total Petroleum Hydrocarbon) gravimetric method; A determinacao de qual o melhor solvente e o melhor tempo de extracao de sedimento em aparato Soxhlet na metodologia do TPH (Total Petroleum Hydrocarbon) gravimetrico

    Energy Technology Data Exchange (ETDEWEB)

    Koike, Renato S.; Lima, Guilherme; Baisch, Paulo R. [Fundacao Universidade Federal do Rio Grande (FURG), RS (Brazil)

    2004-07-01

    There are several methods of TPH (Total Petroleum Hydrocarbons) analysis of petroleum hydrocarbons contaminants in sediment. The TPH gravimetric has been widely used in many studies and in oil spill monitoring case. The present work examined three different solvents (DCM, DCM/N-HEX and N-HEX), in three different times, to the purpose to optimize the contaminants extraction using USEPA 9071 and 3540 reference method. Then was realized analysis of Total Organic Carbon (TOC) for monitoring the reproducible extracts. The sediments used in this experiment was collected in the Cavalos Island, localized in the city of Rio Grande, RS-Brasil. The sediment was 'washed' and after then contaminated with petroleum. The extracts were realized in Soxhlet apparatus, in three different times (4, 8 and 12 hours), and TOC analysis were realized before and after the extraction. The result demonstrated that eight hours with DCM/N-HEX solvent is more indicated for TPH gravimetric in sediment analysis with high concentration of petroleum hydrocarbons. TOC analysis demonstrated inappropriate for monitoring extract reproducibility. (author)

  4. Extraction of S- and N-Compounds from the Mixture of Hydrocarbons by Ionic Liquids as Selective Solvents

    OpenAIRE

    Beata Gabrić; Aleksandra Sander; Marina Cvjetko Bubalo; Dejan Macut

    2013-01-01

    Liquid-liquid extraction is an alternative method that can be used for desulfurization and denitrification of gasoline and diesel fuels. Recent approaches employ different ionic liquids as selective solvents, due to their general immiscibility with gasoline and diesel, negligible vapor pressure, and high selectivity to sulfur- and nitrogen-containing compounds. For that reason, five imidazolium-based ionic liquids and one pyridinium-based ionic liquid were selected for extraction of thiophene...

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

    Science.gov (United States)

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

    2015-11-14

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

  6. The CHC22 clathrin-GLUT4 transport pathway contributes to skeletal muscle regeneration.

    Directory of Open Access Journals (Sweden)

    Sachiko Hoshino

    Full Text Available Mobilization of the GLUT4 glucose transporter from intracellular storage vesicles provides a mechanism for insulin-responsive glucose import into skeletal muscle. In humans, clathrin isoform CHC22 participates in formation of the GLUT4 storage compartment in skeletal muscle and fat. CHC22 function is limited to retrograde endosomal sorting and is restricted in its tissue expression and species distribution compared to the conserved CHC17 isoform that mediates endocytosis and several other membrane traffic pathways. Previously, we noted that CHC22 was expressed at elevated levels in regenerating rat muscle. Here we investigate whether the GLUT4 pathway in which CHC22 participates could play a role in muscle regeneration in humans and we test this possibility using CHC22-transgenic mice, which do not normally express CHC22. We observed that GLUT4 expression is elevated in parallel with that of CHC22 in regenerating skeletal muscle fibers from patients with inflammatory and other myopathies. Regenerating human myofibers displayed concurrent increases in expression of VAMP2, another regulator of GLUT4 transport. Regenerating fibers from wild-type mouse skeletal muscle injected with cardiotoxin also showed increased levels of GLUT4 and VAMP2. We previously demonstrated that transgenic mice expressing CHC22 in their muscle over-sequester GLUT4 and VAMP2 and have defective GLUT4 trafficking leading to diabetic symptoms. In this study, we find that muscle regeneration rates in CHC22 mice were delayed compared to wild-type mice, and myoblasts isolated from these mice did not proliferate in response to glucose. Additionally, CHC22-expressing mouse muscle displayed a fiber type switch from oxidative to glycolytic, similar to that observed in type 2 diabetic patients. These observations implicate the pathway for GLUT4 transport in regeneration of both human and mouse skeletal muscle, and demonstrate a role for this pathway in maintenance of muscle fiber

  7. Extraction of S- and N-compounds from the mixture of hydrocarbons by ionic liquids as selective solvents.

    Science.gov (United States)

    Gabrić, Beata; Sander, Aleksandra; Cvjetko Bubalo, Marina; Macut, Dejan

    2013-01-01

    Liquid-liquid extraction is an alternative method that can be used for desulfurization and denitrification of gasoline and diesel fuels. Recent approaches employ different ionic liquids as selective solvents, due to their general immiscibility with gasoline and diesel, negligible vapor pressure, and high selectivity to sulfur- and nitrogen-containing compounds. For that reason, five imidazolium-based ionic liquids and one pyridinium-based ionic liquid were selected for extraction of thiophene, dibenzothiophene, and pyridine from two model solutions. The influences of hydrodynamic conditions, mass ratio, and number of stages were investigated. Increasing the mass ratio of ionic liquid/model fuel and multistage extraction promotes the desulfurization and denitrification abilities of the examined ionic liquids. All selected ionic liquids can be reused and regenerated by means of vacuum evaporation.

  8. Experimental neurotoxicity and urinary metabolites of the C5-C7 aliphatic hydrocarbons used as glue solvents in shoe manufacture.

    Science.gov (United States)

    Frontali, N; Amantini, M C; Spagnolo, A; Guarcini, A M; Saltari, M C; Brugnone, F; Perbellini, L

    1981-12-01

    Rats were intermittently exposed (9 to 10 h/d, 5 to 6 d/week) to controlled concentrations of single analytical grad solvents in ambient air. After periods ranging from 7 to 30 weeks the animals were perfused with glutaraldehyde and samples of nerves were processed for light microscopy of sections and of teased fibers. Animals treated with n-hexane at 5000 ppm (14 weeks) or 2500 ppm (30 weeks) developed the typical giant axonal degeneration already described in rats treated continuously with 400 to 600 ppm of the same solvent for 7 weeks or more. No such alterations were found in rats subjected to the following intermittent respiratory treatments: n-hexane 500 ppm (30 weeks) or 1500 ppm (14 weeks), cyclohexane 1500 or 2500 (30 weeks), n-pentane 3000 ppm (30 weeks), n-heptane 1500 ppm (30 weeks), 2-methylpentane 1500 ppm (14 weeks), and 3-methylpentane 1500 ppm (14 weeks). The following metabolites were found in the urine of rats according to treatment (in parenthesis): 2-methyl-2-pentanol (2-methylpentane); 3-methyl-2-pentanol and 3-methyl-3-pentanol (3-methylpentane), 2-hexanol, 3-hexanol, gamma-valerolactone, 2,5-dimethylfuran, and 2,5-hexanedione (n-hexane). 2-Hexanol was found to be the main urinary metabolite of n-hexane, while 2,5-hexanedione was present only in a lesser proportion. This feature of rat metabolism suggests that in this species 2,5-hexanedione reaches an effective level at its site of action during intermittent respiratory treatment with n-hexane with difficulty and explains the high concentrations necessary to cause polyneuropathy in rats subjected to this treatment.

  9. Semiautomatic sequential extraction of polycyclic aromatic hydrocarbons and elemental bio-accessible fraction by accelerated solvent extraction on a single particulate matter sample.

    Science.gov (United States)

    Astolfi, Maria Luisa; Di Filippo, Patrizia; Gentili, Alessandra; Canepari, Silvia

    2017-11-01

    We describe the optimization and validation of a sequential extractive method for the determination of the polycyclic aromatic hydrocarbons (PAHs) and elements (Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Se, V and Zn) that are chemically fractionated into bio-accessible and mineralized residual fractions on a single particulate matter filter. The extraction is performed by automatic accelerated solvent extraction (ASE); samples are sequentially treated with dichloromethane/acetone (4:1) for PAHs extraction and acetate buffer (0.01M; pH 4.5) for elements extraction (bio-accessible fraction). The remaining solid sample is then collected and subjected to acid digestion with HNO3:H2O2 (2:1) to determine the mineralized residual element fraction. We also describe a homemade ASE cell that reduces the blank values for most elements; in this cell, the steel frit was replaced by a Teflon pierced disk and a Teflon cylinder was used as the filler. The performance of the proposed method was evaluated in terms of recovery from standard reference material (SRM 1648 and SRM 1649a) and repeatability. The equivalence between the new ASE method and conventional methods was verified for PAHs and for bio-accessible and mineralized residual fractions of elements on PM10 twin filters. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Biological Treatment of Solvent-Based Paint

    Science.gov (United States)

    2011-01-01

    solvent. In addition, hydrocarbon mixtures, aromatic hydrocarbon, and Medium Aliphatic Solvent Naphtha are descriptors used by the manufactures to...Enamel Aromatic Hydrocarbon 14 Mineral Spirits 10 Naphtha 10 Ethyl Benzene 0.21 Xylene 1.0 Sherwin Williams Co Enamel Mineral Spirits 49...Solvent Naphtha 31.5 Non-hazardous Ingredients 68 Parker Paints Enamel Mineral Spirits 17 Naphtha 7 Aromatic Hydrocarbons 3 1,2,4

  11. Cuticular hydrocarbons as queen adoption cues in the invasive Argentine ant.

    Science.gov (United States)

    Vásquez, Gissella M; Schal, Coby; Silverman, Jules

    2008-04-01

    In social insects, individuals typically recognize and behave aggressively towards alien conspecifics, thereby maintaining colony integrity. This is presumably achieved via a nestmate recognition system in which cuticular compounds, usually cuticular hydrocarbons (CHC), of genetic and/or environmental origin serve as recognition cues. Most invasive populations of the Argentine ant, Linepithema humile (Mayr), display minimal nestmate-non-nestmate discrimination, resulting in low levels of intraspecific aggression allowing free movement of workers and queens among nests. However, invasive L. humile in the southeastern United States show relatively high levels of intraspecific aggression, and selectively adopt non-nestmate queens. Using behavioral assays and gas chromatography, we found an association between non-nestmate queen adoption and similarity of the CHC profiles of adopted and host colony queens. Also, nestmate and non-nestmate queen CHC profiles became more similar after adoption by queenless colonies. Furthermore, queens treated with non-nestmate queen CHC had distinct CHC profiles and were generally attacked by nestmate workers. We suggest that in L. humile, CHC are used as queen recognition cues, and that queen recognition errors are more likely to occur when the CHC profiles of non-nestmate and host colony queens are similar. Our findings provide further evidence for the complex and dynamic nature of L. humile nestmate discrimination, which may in part underlie the success of introduced populations of this invasive ant.

  12. A cross-battery, reference variable, confirmatory factor analytic investigation of the CHC taxonomy.

    Science.gov (United States)

    Reynolds, Matthew R; Keith, Timothy Z; Flanagan, Dawn P; Alfonso, Vincent C

    2013-08-01

    The Cattell-Horn-Carroll (CHC) taxonomy has been used to classify and describe human cognitive abilities. The ability factors derived from the CHC taxonomy are often assumed to be invariant across multiple populations and intelligence batteries, which is an important assumption for research and assessment. In this study, data from five different test batteries that were collected during separate Kaufman Assessment Battery for Children-Second Edition (KABC-II; Kaufman & Kaufman, 2004) concurrent validity studies were factor-analyzed jointly. Because the KABC-II was administered to everyone in the validity studies, it was used as a reference battery to link the separate test batteries in a "cross-battery" confirmatory factor analysis. Some findings from this analysis were that CHC-based test classifications based on theory and prior research were straightforward and accurate, a first-order Fluid/Novel Reasoning (Gf) factor was equivalent to a second-order g factor, and sample heterogeneity related to SES and sex influenced factor loadings. It was also shown that a reference variable approach, used in studies that incorporate planned missingness into data collection, may be used successfully to analyze data from several test batteries and studies. One implication from these findings is that CHC theory should continue to serve as a useful guide that can be used for intelligence research, assessment, and test development.

  13. Contact solid-phase microextraction with uncoated glass and polydimethylsiloxane-coated fibers versus solvent sampling for the determination of hydrocarbons in adhesion secretions of Madagascar hissing cockroaches Gromphadorrhina portentosa (Blattodea) by gas chromatography-mass spectrometry.

    Science.gov (United States)

    Gerhardt, Heike; Schmitt, Christian; Betz, Oliver; Albert, Klaus; Lämmerhofer, Michael

    2015-04-03

    Molecular profiles of adhesion secretions of Gromphadorrhina portentosa (Madagascar hissing cockroach, Blattodea) were investigated by gas chromatography mass spectrometry with particular focus on a comprehensive analysis of linear and branched hydrocarbons. For this purpose, secretions from the tarsi (feet), possibly contributing to adhesion on smooth surfaces, and control samples taken from the tibiae (lower legs), which contain general cuticular hydrocarbons that are supposed to be not involved in the biological adhesion function, were analyzed and their molecular fingerprints compared. A major analytical difficulty in such a study constitutes the representative, spatially controlled, precise and reproducible sampling from a living insect as well as the minute quantities of insect secretions on both tarsi and tibiae. Thus, three different in vivo sampling methods were compared in terms of sampling reproducibility and extraction efficiency by replicate measurement of samples from tarsi and tibiae. While contact solid-phase microextraction (SPME) with a polydimethylsiloxane (PDMS) fiber showed higher peak intensities, a self-made uncoated glass fiber had the best repeatability in contact-SPME sampling. Chromatographic profiles of these two contact-SPME sampling methods were statistically not significantly different. Inter-individual variances were larger than potentially existing minor differences in molecular patterns of distinct sampling methods. Sampling by solvent extraction was time consuming, showed lower sensitivities and was less reproducible. In general, sampling by contact-SPME with a cheap glass fiber turned out to be a viable alternative to PDMS-SPME sampling. Hydrocarbon patterns of the tarsal adhesion secretions were qualitatively similar to those of epicuticular hydrocarbon profiles of the tibiae. However, hydrocarbons were in general less abundant in tarsal secretions than secretions from tibiae.

  14. Hydrocarbon Patterns and Mating Behaviour in Populations of Drosophila yakuba

    Directory of Open Access Journals (Sweden)

    Béatrice Denis

    2015-10-01

    Full Text Available Drosophila yakuba is widespread in Africa. Here we compare the cuticular hydrocarbon (CHC profiles and mating behavior of mainland (Kounden, Cameroon and island (Mayotte, Sao-Tome, Bioko populations. The strains each had different CHC profiles: Bioko and Kounden were the most similar, while Mayotte and Sao-Tome contained significant amounts of 7-heptacosene. The CHC profile of the Sao-Tome population differed the most, with half the 7-tricosene of the other populations and more 7-heptacosene and 7-nonacosene. We also studied the characteristics of the mating behavior of the four strains: copulation duration was similar but latency times were higher in Mayotte and Sao-Tome populations. We found partial reproductive isolation between populations, especially in male-choice experiments with Sao-Tome females.

  15. 40 CFR Table 5 to Subpart Oooo of... - Default Organic HAP Mass Fraction for Petroleum Solvent Groups a

    Science.gov (United States)

    2010-07-01

    ..., Mineral Spirits 150 EC, Naphtha, Mixed Hydrocarbon, Aliphatic Hydrocarbon, Aliphatic Naphtha, Naphthol Spirits, Petroleum Spirits, Petroleum Oil, Petroleum Naphtha, Solvent Naphtha, Solvent Blend. c Medium-flash Naphtha, High-flash Naphtha, Aromatic Naphtha, Light Aromatic Naphtha, Light Aromatic Hydrocarbons...

  16. Flexible origin of hydrocarbon/pheromone precursors in Drosophila melanogaster.

    Science.gov (United States)

    Wicker-Thomas, Claude; Garrido, Damien; Bontonou, Gwénaëlle; Napal, Laura; Mazuras, Nicolas; Denis, Béatrice; Rubin, Thomas; Parvy, Jean-Philippe; Montagne, Jacques

    2015-11-01

    In terrestrial insects, cuticular hydrocarbons (CHCs) provide protection from desiccation. Specific CHCs can also act as pheromones, which are important for successful mating. Oenocytes are abdominal cells thought to act as specialized units for CHC biogenesis that consists of long-chain fatty acid (LCFA) synthesis, optional desaturation(s), elongation to very long-chain fatty acids (VLCFAs), and removal of the carboxyl group. By investigating CHC biogenesis in Drosophila melanogaster, we showed that VLCFA synthesis takes place only within the oenocytes. Conversely, several pathways, which may compensate for one another, can feed the oenocyte pool of LCFAs, suggesting that this step is a critical node for regulating CHC synthesis. Importantly, flies deficient in LCFA synthesis sacrificed their triacylglycerol stores while maintaining some CHC production. Moreover, pheromone production was lower in adult flies that emerged from larvae that were fed excess dietary lipids, and their mating success was lower. Further, we showed that pheromone production in the oenocytes depends on lipid metabolism in the fat tissue and that fatty acid transport protein, a bipartite acyl-CoA synthase (ACS)/FA transporter, likely acts through its ACS domain in the oenocyte pathway of CHC biogenesis. Our study highlights the importance of environmental and physiological inputs in regulating LCFA synthesis to eventually control sexual communication in a polyphagous animal.

  17. CHC: A Robust P2P Overlay Network with Simple Routing and Small-World Features

    Directory of Open Access Journals (Sweden)

    Wenjun Xiao

    2011-08-01

    Full Text Available Almost all recent researches on P2P systems focus on howto build a highly usable P2P overlay network. Researchersinclude small routing table, short query path and goodrobustness into their design objectives of overlay topology. Inthis paper, we present a general group theory method anddefine a new Cayley graph. Based on this Cayley graph, wepropose a novel P2P overlay network called CHC, which hassimple routing (searching scheme and many other excellentproperties such as short query path, high clustering and goodrobustness because of its symmetry. The performance isevaluated by simulation to show that CHC possesses shorterquery path length and higher clustering and better robustnessthan several popular P2P overlay networks such as Chord andUlysses.

  18. Alternative Green Solvents Project

    Science.gov (United States)

    Maloney, Phillip R.

    2012-01-01

    Necessary for safe and proper functioning of equipment. Mainly halogenated solvents. Tetrachloride, Trichloroethylene (TCE), CFC-113. No longer used due to regulatory/safety concerns. Precision Cleaning at KSC: Small % of total parts. Used for liquid oxygen (LOX) systems. Dual solvent process. Vertrel MCA (decafluoropentane (DFP) and trons-dichloroethylene) HFE-7100. DFP has long term environmental concerns. Project Goals: a) Identify potential replacements. b) 22 wet chemical processes. c) 3 alternative processes. d) Develop test procedures. e) Contamination and cleaning. f) Analysis. g) Use results to recommend alternative processes. Conclusions: a) No alternative matched Vertrel in this study. b) No clear second place solvent. c) Hydrocarbons- easy; Fluorinated greases- difficult. d) Fluorinated component may be needed in replacement solvent. e) Process may need to make up for shortcoming of the solvent. f) Plasma and SCC02 warrant further testing.

  19. Fatty acid alkyl esters as solvents: An evaluation of the kauri-butanol value. Comparison to hydrocarbons, dimethyl diesters and other oxygenates

    Science.gov (United States)

    Esters, most commonly methyl esters, of vegetable oils or animal fats or other lipid feedstocks have found increasing use as an alternative diesel fuel known as biodiesel. However, biodiesel also has good solvent properties, a feature rendered additionally attractive by its biodegradability, low tox...

  20. Cuticle hydrocarbons in saline aquatic beetles

    Directory of Open Access Journals (Sweden)

    María Botella-Cruz

    2017-07-01

    Full Text Available Hydrocarbons are the principal component of insect cuticle and play an important role in maintaining water balance. Cuticular impermeability could be an adaptative response to salinity and desiccation in aquatic insects; however, cuticular hydrocarbons have been poorly explored in this group and there are no previous data on saline species. We characterized cuticular hydrocarbons of adults and larvae of two saline aquatic beetles, namely Nebrioporus baeticus (Dytiscidae and Enochrus jesusarribasi (Hydrophilidae, using a gas chromatograph coupled to a mass spectrometer. The CHC profile of adults of both species, characterized by a high abundance of branched alkanes and low of unsaturated alkenes, seems to be more similar to that of some terrestrial beetles (e.g., desert Tenebrionidae compared with other aquatic Coleoptera (freshwater Dytiscidae. Adults of E. jesusarribasi had longer chain compounds than N. baeticus, in agreement with their higher resistance to salinity and desiccation. The more permeable cuticle of larvae was characterized by a lower diversity in compounds, shorter carbon chain length and a higher proportion of unsaturated hydrocarbons compared with that of the adults. These results suggest that osmotic stress on aquatic insects could exert a selection pressure on CHC profile similar to aridity in terrestrial species.

  1. Avaliação de solventes de extração por ultrassom usando-se cromatografia líquida de alta eficiência para a determinação de hidrocarbonetos policíclicos aromáticos em solos contaminados Evaluation of solvent extraction by ultrasound by using high performance liquid chromatography for the determination of polycyclic aromatic hydrocarbons in contaminated soils

    Directory of Open Access Journals (Sweden)

    Jussara Aparecida Oliveira Cotta

    2009-01-01

    Full Text Available A method using ultrasonication extraction for the determination of 17 polycyclic aromatic hydrocarbons (PAHs, selected by the USEPA and NIOSH as "consent decree" priority pollutants, in soil by High Performance Liquid Chromatography (HPLC was studied. Separation and detection were completed in 20 min with a C18 columm, acetonitrile-water gradient elution and ultraviolet absorption and fluorescence detections. The detection limits, for a 10 µL of solution injection, were less than 9,917 ng/g in UV detection and less than 1,866 ng/g in fluorescence detection. Several organic solvents were tested for extraction of the 17 PAHs from soils. Acetone was the best solvent among the three solvents tested, and the order of the extraction efficiencies was: acetone>methanol>acetonitrile. Ultrasonication using acetone as solvent extraction was used to evaluate the biodegradation of those compounds in contaminated soil during a vermicomposting process.

  2. Hydrocarbon pneumonia

    Science.gov (United States)

    Pneumonia - hydrocarbon ... Coughing Fever Shortness of breath Smell of a hydrocarbon product on the breath Stupor (decreased level of ... Most children who drink or inhale hydrocarbon products and develop ... hydrocarbons may lead to rapid respiratory failure and death.

  3. Separation and identification of hydrocarbons and other volatile compounds from cultures of Aspergillus niger by GC–MS using two different capillary columns and solvents

    Directory of Open Access Journals (Sweden)

    Shafiquzzaman Siddiquee

    2015-05-01

    Full Text Available A simple, fast, repeatable, and less laborious sample-preparation protocol based on gas chromatography–mass spectrometry was developed and applied for the analysis of bioactive compounds derived from the filamentous fungus Aspergillus niger strain SS10. The match factors for the spectra of the samples with reference to the mass-spectral library of fungal volatile compounds were determined and used to study the complex hydrocarbons and other volatile compounds that were separated using two different capillary columns and nonpolar and medium-polar stationary phases. More than 295 volatile compounds (spectral match factor of at least 90%, such as normal saturated hydrocarbons (C7–C30, cyclohexane, cyclopentane, fatty acids, alcohols, esters, sulfur- and bromo-containing compounds, simple pyrane, and benzene derivatives, were identified. Most of these compounds have not been reported earlier. The method described in this article is a suitable research tool for the determination of volatile compounds from the cultures of A. niger.

  4. Implementing CHC to Counter Shoulder Surfing Attack in PassPoint – Style Graphical Passwords

    Directory of Open Access Journals (Sweden)

    M. Joshuva

    2011-05-01

    Full Text Available Graphical passwords are an alternative to existing alphanumeric passwords. In Graphical passwords users click on images than type a long, complex password. Passpoints scheme is one of the Graphical user authentication techniques. In this method the password is represented by multiple clicks on a single image. One of the advantages with Passpoints scheme is that, a user can click on any place in the image as a click point. Graphical authentication suffers a major drawback of Shoulder-surfing. Shoulder-surfing refers to someone observing the user’s action as the user enters a password. Due to this, the user’s action can be monitored by the attacker or it can be captured using recording devices such as camera. Sobrado and Birget suggested Convex Hull Click (CHC scheme to counter shoulder-surfing using PassIcons which is different from PassPoint scheme. In this paper, we described how CHC is implemented in Passpoint-sheme to counter Shoulder Surfing Attack.

  5. Solvent degradation products in nuclear fuel processing solvents

    Energy Technology Data Exchange (ETDEWEB)

    Shook, H.E. Jr.

    1988-06-01

    The Savannah River Plant uses a modified Purex process to recover enriched uranium and separate fission products. This process uses 7.5% tri-n-butyl phosphate (TBP) dissolved in normal paraffin hydrocarbons for the solvent extraction of a nitric acid solution containing the materials to be separated. Periodic problems in product decontamination result from solvent degradation. A study to improve process efficiency has identified certain solvent degradation products and suggested mitigation measures. Undecanoic acid, lauric acid, and tridecanoic acid were tentatively identified as diluent degradation products in recycle solvent. These long-chain organic acids affect phase separation and lead to low decontamination factors. Solid phase extraction (SPE) was used to concentrate the organic acids in solvent prior to analysis by high performance liquid chromatography (HPLC). SPE and HPLC methods were optimized in this work for analysis of decanoic acid, undecanoic acid, and lauric acid in solvent. Accelerated solvent degradation studies with 7.5% TBP in normal paraffin hydrocarbons showed that long-chain organic acids and long-chain alkyl butyl phosphoric acids are formed by reactions with nitric acid. Degradation of both tributyl phosphate and hydrocarbon can be minimized with purified normal paraffin replacing the standard grade presently used. 12 refs., 1 fig., 3 tabs.

  6. Selection and evaluation of alternative solvents for caprolactam extraction

    NARCIS (Netherlands)

    Delden, van Mathijs L.; Kuipers, Norbert J.M.; Haan, de André B.

    2006-01-01

    Because of the strict legislation for currently applied solvents in the industrial extraction of caprolactam, being benzene, toluene and chlorinated hydrocarbons, a need exists for alternative, environmentally benign solvents. An experimental screening procedure consisting of several steps was used

  7. Variations on a theme: diversification of cuticular hydrocarbons in a clade of cactophilic Drosophila

    Directory of Open Access Journals (Sweden)

    Jackson Larry L

    2011-06-01

    Full Text Available Abstract Background We characterized variation and chemical composition of epicuticular hydrocarbons (CHCs in the seven species of the Drosophila buzzatii cluster with gas chromatography/mass spectrometry. Despite the critical role of CHCs in providing resistance to desiccation and involvement in communication, such as courtship behavior, mating, and aggregation, few studies have investigated how CHC profiles evolve within and between species in a phylogenetic context. We analyzed quantitative differences in CHC profiles in populations of the D. buzzatii species cluster in order to assess the concordance of CHC differentiation with species divergence. Results Thirty-six CHC components were scored in single fly extracts with carbon chain lengths ranging from C29 to C39, including methyl-branched alkanes, n-alkenes, and alkadienes. Multivariate analysis of variance revealed that CHC amounts were significantly different among all species and canonical discriminant function (CDF analysis resolved all species into distinct, non-overlapping groups. Significant intraspecific variation was found in different populations of D. serido suggesting that this taxon is comprised of at least two species. We summarized CHC variation using CDF analysis and mapped the first five CHC canonical variates (CVs onto an independently derived period (per gene + chromosome inversion + mtDNA COI gene for each sex. We found that the COI sequences were not phylogenetically informative due to introgression between some species, so only per + inversion data were used. Positive phylogenetic signal was observed mainly for CV1 when parsimony methods and the test for serial independence (TFSI were used. These results changed when no outgroup species were included in the analysis and phylogenetic signal was then observed for female CV3 and/or CV4 and male CV4 and CV5. Finally, removal of divergent populations of D. serido significantly increased the amount of phylogenetic signal as

  8. Variations on a theme: diversification of cuticular hydrocarbons in a clade of cactophilic Drosophila.

    Science.gov (United States)

    de Oliveira, Cássia C; Manfrin, Maura H; Sene, Fábio de M; Jackson, Larry L; Etges, William J

    2011-06-23

    We characterized variation and chemical composition of epicuticular hydrocarbons (CHCs) in the seven species of the Drosophila buzzatii cluster with gas chromatography/mass spectrometry. Despite the critical role of CHCs in providing resistance to desiccation and involvement in communication, such as courtship behavior, mating, and aggregation, few studies have investigated how CHC profiles evolve within and between species in a phylogenetic context. We analyzed quantitative differences in CHC profiles in populations of the D. buzzatii species cluster in order to assess the concordance of CHC differentiation with species divergence. Thirty-six CHC components were scored in single fly extracts with carbon chain lengths ranging from C29 to C39, including methyl-branched alkanes, n-alkenes, and alkadienes. Multivariate analysis of variance revealed that CHC amounts were significantly different among all species and canonical discriminant function (CDF) analysis resolved all species into distinct, non-overlapping groups. Significant intraspecific variation was found in different populations of D. serido suggesting that this taxon is comprised of at least two species. We summarized CHC variation using CDF analysis and mapped the first five CHC canonical variates (CVs) onto an independently derived period (per) gene + chromosome inversion + mtDNA COI gene for each sex. We found that the COI sequences were not phylogenetically informative due to introgression between some species, so only per + inversion data were used. Positive phylogenetic signal was observed mainly for CV1 when parsimony methods and the test for serial independence (TFSI) were used. These results changed when no outgroup species were included in the analysis and phylogenetic signal was then observed for female CV3 and/or CV4 and male CV4 and CV5. Finally, removal of divergent populations of D. serido significantly increased the amount of phylogenetic signal as up to four out of five CVs then displayed

  9. Do Cuticular Hydrocarbons Provide Sufficient Information for Optimal Sex Allocation in the Ant Formica exsecta?

    DEFF Research Database (Denmark)

    van Zweden, Jelle Stijn; Vitikainen, Emma; D'Ettorre, Patrizia

    2011-01-01

    of CHC recognition cues reflects colony kin structure in the ant Formica exsecta. Our results show that CHC variability does not covary with kin structure or the overall genetic diversity of the colony, and that patrilines and matrilines can have distinct CHC profiles in some but not all colonies......Split sex ratio theory predicts that when kin structure varies among colonies of social insects, in order to maximize the inclusive fitness, colonies with relatively high sister-sister relatedness should specialize in producing reproductive females, whereas in those with relatively low sister......-sister relatedness workers should bias their sex ratio towards males. However, in order to achieve this, workers need to be able to reliably assess the type of colony in which they live. The information on colony kin structure may be encoded in cuticular hydrocarbons (CHCs), assuming that genetic variability...

  10. Method for analyzing solvent extracted sponge core

    Energy Technology Data Exchange (ETDEWEB)

    Ellington, W.E.; Calkin, C.L.

    1988-11-22

    For use in solvent extracted sponge core measurements of the oil saturation of earth formations, a method is described for quantifying the volume of oil in the fluids resulting from such extraction. The method consists of: (a) separating the solvent/oil mixture from the water in the extracted fluids, (b) distilling at least a portion of the solvent from the solvent/oil mixture substantially without co-distillation or loss of the light hydrocarbons in the mixture, (c) determining the volume contribution of the solvent remaining in the mixture, and (d) determining the volume of oil removed from the sponge by substracting the determined remaining solvent volume.

  11. The role of the Environmental Specimen Bank in environmental monitoring: The example of CHC in selected matrices; Die Rolle der Umweltprobenbank in der Umweltueberwachung am Beispiel von chlorierten Kohlenwasserstoffen in ausgewaehlten Matrizes

    Energy Technology Data Exchange (ETDEWEB)

    Marth, P.; Kettrup, A. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Oekologische Chemie]|[Technische Univ. Muenchen, Freising (Germany). Lehrstuhl fuer Oekologische Chemie und Umweltanalytik; Schramm, K.W.; Henkelmann, B.; Wolf, A.; Oxynos, K.; Schmitzer, J. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Oekologische Chemie

    1999-03-01

    For precautionary environmental protection the Environmental Specimen Bank (ESB) has been successfully established as a permanent environmental surveillance tool in Germany. The presented monitoring results on chlorinated hydrocarbons (CHC) show very clearly the effects of political decisions and can be used for the identification of pollutant sources. The CHC burden of breams (Abramis brama) from five German rivers (Elbe, Rhein, Saar, Mulde, Saale) gives an current overview of the pollution situation of different limnic ecosystems in Germany. A calculation model about the distribution of organic pollutants between different tissues offers the possibility to predict concentrations in liver and muscle of breams. Legislative emission restrictions have led to a significant decrease of dioxin levels in herring gull (Larus argentatus) eggs between 1988-1996. (orig.) [Deutsch] Die Umweltprobenbank des Bundes hat sich im Rahmen der Oekologischen Umweltbeobachtung zu einem wichtigen und permanenten Instrument der Umweltpolitik entwickelt. Neben der Langzeitkonservierung fuer zukuenftige Forschungsaufgaben wird am Beispiel der chlorierten Kohlenwasserstoffe demonstriert, dass das durchgefuehrte Monitoring-Programm als Nachweis fuer die Effektivitaet gesetzlicher Massnahmen und zur Identifizierung von Schadstoffeintragsquellen genutzt werden kann. Der vorliegende Beitrag vermittelt am Beispiel der Brassen (Abramis brama) als Akkumulationsindikator einen aktuellen und raeumlich differenzierten Ueberblick ueber die chlororganische Belastungssituation bundesdeutscher Gewaesser (Elbe, Rhein, Saar, Mulde, Saale). Betrachtungen zur Verteilung organischer Chemikalien zwischen Gewebetypen von Brassen zeigen, dass sich die Verteilung der Schadstoffkonzentrationen in Leber und Muskel mit einem geringen Fehler errechnen laesst. Die Dioxingehalte von Silbermoeweneiern (Larus argentatus) belegen, dass die Belastung durch strengere Emissionsgrenzwerte seit Beginn der neunziger Jahre

  12. Investigation of an Outbreak of Diphtheria in Dabela Village of Amirgagh Taluka and CHC, Banaskantha, Gujarat

    Directory of Open Access Journals (Sweden)

    Niti Talsania, Jignesh Chauhan, Himanshu Nayak, Chintul Shah, Krunal Modi, Jaydeep devaliya

    2011-01-01

    Full Text Available As outbreak of diphtheria reflects the impact of immunization outbreak investigation was carried out to assess the diphtheria outbreak pattern and case fatality rate in Dabela Village of Amirgagh Taluka and CHC, District, Banaskantha, Gujarat in 2007. Population stabilization, poverty alleviation, lifestyle modification, surveillance and control of communicable and non-communicable diseases constitute the major challenges demanding urgent attention in the future. Vaccine was efficacious among those who received >4 doses. The proportion of the population receiving boosters was low, especially among Muslims. We recommend increasing booster dose coverage. We investigated epidemic to 1 describe the epidemiology of diphtheria in terms of time, place, and person; 2 estimate vaccine coverage; and 3 to do SWOT analysis in Immunization services.4 To suggest successful vaccination.

  13. An alternative Cattell-Horn-Carroll (CHC) factor structure of the WAIS-IV: age invariance of an alternative model for ages 70-90.

    Science.gov (United States)

    Niileksela, Christopher R; Reynolds, Matthew R; Kaufman, Alan S

    2013-06-01

    The Wechsler Adult Intelligence Scale--Fourth Edition (WAIS-IV) is by the far the most popular intelligence test for the assessment of adults in clinical and neuropsychological practice. Despite a number of studies examining the factor structure of the WAIS-IV from a Cattell-Horn-Carroll (CHC) perspective (Benson, Hulac, & Kranzler, 2010; Ward, Bergman, & Hebert, 2012), a CHC interpretation of the WAIS-IV for individuals ages 70 and above has been absent from the literature. The exclusion of individuals ages 70 and above in previous research is likely due to the absence of several key supplemental subtests used to create a full CHC model. We provide an alternative five-factor CHC model of the WAIS-IV which includes only the subtests administered to individuals ages 70 and above in the standardization sample. Our results show (a) the alternative CHC model fits the data well; (b) this alternative CHC model met criteria for partial strict measurement invariance across the life span (only Similarities showed noninvariance) using strict criteria; (c) the five factors for ages 70-90 measure the same five CHC broad abilities identified in previous analyses reported for ages 16-69; and (d) the five-factor CHC solution for ages 70-90 is valid for the entire WAIS-IV age range and can be used whenever examiners administer the core battery but opt not to administer supplemental subtests. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  14. A visit to CHC of a larger number of women. JICA Reproductive Health Project. Yen Than district.

    Science.gov (United States)

    Trinh Xuan Hong

    1999-01-01

    The situation of the Bac Than Commune Health Center (CHC) in Yen Than District, Vietnam is reported. Promotion of education, improvement in health care, and economic development are the strategic programs for improving the commune people's standard of living. For the promotion of education, the CHC upgraded educational facilities and trained teachers on the use of efficient teaching methods. In order to generate a bigger income, efforts are exerted to promote the development of agriculture by producing agricultural products that are popular and sell high in the market. These activities have yielded positive results. Many students are doing well in their classes and are attending universities and the per capita yield of products has increased. For the improvement in health care, the Japan International Cooperation Agency Reproductive Health project has contributed much to the CHC. The three activities observed were 1) implementation of information, education and communication activities; 2) training of health staff members; and 3) renovation of the health facility. Such improvements have led to a visit to CHC of a larger number of women for gynecological examinations and prenatal check-ups and safe delivery.

  15. The Role of Cattell-Horn-Carroll (CHC) Cognitive Abilities in Predicting Writing Achievement during the School-Age Years

    Science.gov (United States)

    Cormier, Damien C.; Bulut, Okan; McGrew, Kevin S.; Frison, Jessica

    2016-01-01

    Writing is a complex academic task--it involves numerous mental processes. Given the necessity for developing writing skills from elementary to secondary school, this study aimed to investigate the role of broad cognitive abilities derived from the Cattell-Horn-Carroll (CHC) theory of intelligence in predicting skills associated with writing…

  16. Quantitative Hydrocarbon Surface Analysis

    Science.gov (United States)

    Douglas, Vonnie M.

    2000-01-01

    The elimination of ozone depleting substances, such as carbon tetrachloride, has resulted in the use of new analytical techniques for cleanliness verification and contamination sampling. The last remaining application at Rocketdyne which required a replacement technique was the quantitative analysis of hydrocarbons by infrared spectrometry. This application, which previously utilized carbon tetrachloride, was successfully modified using the SOC-400, a compact portable FTIR manufactured by Surface Optics Corporation. This instrument can quantitatively measure and identify hydrocarbons from solvent flush of hardware as well as directly analyze the surface of metallic components without the use of ozone depleting chemicals. Several sampling accessories are utilized to perform analysis for various applications.

  17. 40 CFR Table 7 to Subpart Kkkk of... - Default Organic HAP Mass Fraction for Petroleum Solvent Groups a

    Science.gov (United States)

    2010-07-01

    ..., Naphtha, Mixed Hydrocarbon, Aliphatic Hydrocarbon, Aliphatic Naphtha, Naphthol Spirits, Petroleum Spirits, Petroleum Oil, Petroleum Naphtha, Solvent Naphtha, Solvent Blend. c E.g., Medium-flash Naphtha, High-flash Naphtha, Aromatic Naphtha, Light Aromatic Naphtha, Light Aromatic Hydrocarbons, Aromatic Hydrocarbons...

  18. Premating isolation is determined by larval rearing substrates in cactophilic Drosophila mojavensis. IX. Host plant and population specific epicuticular hydrocarbon expression influences mate choice and sexual selection.

    Science.gov (United States)

    Havens, J A; Etges, W J

    2013-03-01

    Sexual signals in cactophilic Drosophila mojavensis include cuticular hydrocarbons (CHCs), contact pheromones that mediate female discrimination of males during courtship. CHCs, along with male courtship songs, cause premating isolation between diverged populations, and are influenced by genotype × environment interactions caused by different host cacti. CHC profiles of mated and unmated adult flies from a Baja California and a mainland Mexico population of D. mojavensis reared on two host cacti were assayed to test the hypothesis that male CHCs mediate within-population female discrimination of males. In multiple choice courtship trials, mated and unmated males differed in CHC profiles, indicating that females prefer males with particular blends of CHCs. Mated and unmated females significantly differed in CHC profiles as well. Adults in the choice trials had CHC profiles that were significantly different from those in pair-mated adults from no-choice trials revealing an influence of sexual selection. Females preferred different male CHC blends in each population, but the influence of host cactus on CHC variation was significant only in the mainland population indicating population-specific plasticity in CHCs. Different groups of CHCs mediated female choice-based sexual selection in each population suggesting that geographical and ecological divergence has the potential to promote divergence in mate communication systems.

  19. Electrochemical decomposition of chlorinated hydrocarbons

    OpenAIRE

    McGee, Gerard Anthony

    1993-01-01

    This work involves the characterisation of the electrochemical decomposition of chlorinated hydrocarbons. A variety of methods were employed involving the use of catalytic reagents to enhance the rate at which chlorinated organic compounds are reduced. The first reagent used was oxygen which was electrochemically reduced to superoxide in nonaqueous solvents. Superoxide is a reactive intermediate and decomposes chlorinated hydrocarbons. However it was found that since the rate of reaction betw...

  20. 基于轻质萃取剂的溶剂去乳化分散液-液微萃取-气相色谱法测定水样中多环芳烃%Low-density solvent-based solvent demulsification dispersive liquid-liquid microextraction combined with gas chromatography for determination of polycyclic aromatic hydrocarbons in water samples

    Institute of Scientific and Technical Information of China (English)

    祝本琼; 陈浩; 李胜清

    2012-01-01

    A novel method of low-density solvent-based solvent demulsification dispersive liquid-liquid microextraction (SD-DLLME) was developed for the determination of eight polycyclic aromatic hydrocarbons ( PAHs) in water samples by gas chromatography-flame ionization detection (GC-FID). Conventional DLLME methods usually employ organic solvents heavier than water as the extraction solvents and achieve the phase separation through centrifugation. On the contrary, in this proposed extraction procedure, a mixture of low-density extraction solvent (toluene) and dispersive solvent (acetone) was injected into the aqueous sample solution to form an emulsion. A demulsification solvent (acetonitrile) was then injected into the aqueous solution to break up the emulsion, which turned clear quickly and was separated into two layers. The upper layer (toluene) was collected and analyzed by GC. No centrifugation was required in this procedure. Factors affecting the extraction efficiency such as the type and volume of dispersive solvent, extraction solvent and de-emulsifier were investigated in detail. Under the optimized conditions, the proposed method provided a good linearity in the range of 20 - 500 μg/L (r2 = 0. 994 2 - 0. 999 9). The limits of detection (S/N = 3) were in the range of 0. 52 - 5. 11 μg/L. The relative standard deviations (RSDs) for the determination of 40 μg/LPAHs were in the range of 2. 2% - 13. 6% (n = 5). The proposed method is fast, efficient and convenient. It has been successfully applied to the determination of PAHs in natural water samples with the spiked recoveries of 80. 2% - 115. 1%.%以密度小于水的轻质溶剂为萃取剂,建立了无需离心步骤的溶剂去乳化分散液-液微萃取-气相色谱( SD-DLLME-GC)测定水样中多环芳烃的新方法.传统分散液-液微萃取技术一般采用密度大于水的有机溶剂为萃取剂,并需要通过离心步骤促进分相.而本方法以密度比水小的轻质溶剂

  1. The Mutasynthetic Production of CHC-B1 from a Streptomyces avermitilis Mutant in the Presence of Cyclohexanecarboxylic Acid%阿维菌素衍生物CHC-B1的突变生物合成

    Institute of Scientific and Technical Information of China (English)

    姜薇; 汪洋; 张晓琳; 郭伟群; 刘娣

    2009-01-01

    利用成功构建的基因缺失载体pLJ04(pKC1139∶∶△bkdF+△bkdH)对阿维菌素(avennectin)高产菌阿维链霉菌(Streptomyces avermitilis)76-02-e的bkdFGH基因进行缺失,获得的bkdFGH缺失突变株经过摇瓶发酵和HPLC检测,发现该突变株完全丧失了产生阿维菌素的能力.2-甲基丁酸及异丁酸的前体添加试验表明,当有外源前体存在时,突变株又能恢复阿维菌素合成的能力.将该bkdFGH基因缺失突变株命名为S.avermitilis bkd76-3.环己羧酸(CHC)前体添加试验及HPLC检测发现存在4种产物,经LC/MS分析验证,其中两种产物分别为CHC-B1和CHC-A2.

  2. Improved efficiency of extraction of polycyclic aromatic hydrocarbons (PAHs) from the National Institute of Standards and Technology (NIST) Standard Reference Material Diesel Particulate Matter (SRM 2975) using accelerated solvent extraction.

    Science.gov (United States)

    Masala, Silvia; Ahmed, Trifa; Bergvall, Christoffer; Westerholm, Roger

    2011-12-01

    The efficiency of extraction of polycyclic aromatic hydrocarbons (PAHs) with molecular masses of 252, 276, 278, 300, and 302 Da from standard reference material diesel particulate matter (SRM 2975) has been investigated using accelerated solvent extraction (ASE) with dichloromethane, toluene, methanol, and mixtures of toluene and methanol. Extraction of SRM 2975 using toluene/methanol (9:1, v/v) at maximum instrumental settings (200 °C, 20.7 MPa, and five extraction cycles) with 30-min extraction times resulted in the following elevations of the measured concentration when compared with the certified and reference concentrations reported by the National Institute of Standards and Technology (NIST): benzo[b]fluoranthene, 46%; benzo[k]fluoranthene, 137%; benzo[e]pyrene, 103%; benzo[a]pyrene, 1,570%; perylene, 37%; indeno[1,2,3-cd]pyrene, 41%; benzo[ghi]perylene, 163%; and coronene, 361%. The concentrations of the following PAHs were comparable to the reference values assigned by NIST: indeno[1,2,3-cd]fluoranthene, dibenz[a,h]anthracene, and picene. The measured concentration of dibenzo[a,e]-pyrene was lower than the information value reported by the NIST. The measured concentrations of other highly carcinogenic PAHs (dibenzo[a,l]pyrene, dibenzo[a,i]pyrene, and dibenzo[a,h]pyrene) in SRM 2975 are also reported. Comparison of measurements using the optimized ASE method and using similar conditions to those applied by the NIST for the assignment of PAH concentrations in SRM 2975 indicated that the higher values obtained in the present study were associated with more complete extraction of PAHs from the diesel particulate material. Re-extraction of the particulate samples demonstrated that the deuterated internal standards were more readily recovered than the native PAHs, which may explain the lower values reported by the NIST. The analytical results obtained in the study demonstrated that the efficient extraction of PAHs from SRM 2975 is a critical requirement for the

  3. Solvent substitution

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    The DOE Environmental Restoration and Waste Management Office of Technology Development and the Air Force Engineering and Services Center convened the First Annual International Workshop on Solvent Substitution on December 4--7, 1990. The primary objectives of this joint effort were to share information and ideas among attendees in order to enhance the development and implementation of required new technologies for the elimination of pollutants associated with industrial use of hazardous and toxic solvents; and to aid in accelerating collaborative efforts and technology transfer between government and industry for solvent substitution. There were workshop sessions focusing on Alternative Technologies, Alternative Solvents, Recovery/Recycling, Low VOC Materials and Treatment for Environmentally Safe Disposal. The 35 invited papers presented covered a wide range of solvent substitution activities including: hardware and weapons production and maintenance, paint stripping, coating applications, printed circuit boards, metal cleaning, metal finishing, manufacturing, compliance monitoring and process control monitoring. This publication includes the majority of these presentations. In addition, in order to further facilitate information exchange and technology transfer, the US Air Force and DOE solicited additional papers under a general Call for Papers.'' These papers, which underwent review and final selection by a peer review committee, are also included in this combined Proceedings/Compendium. For those involved in handling, using or managing hazardous and toxic solvents, this document should prove to be a valuable resource, providing the most up-to-date information on current technologies and practices in solvent substitution. Individual papers are abstracted separated.

  4. Chlorinated Hydrocarbon Degradation in Plants: Mechanisms and Enhancement of Phytoremediation of Groundwater Contamination

    Energy Technology Data Exchange (ETDEWEB)

    Stuart Strand

    2004-09-27

    The research objectives for this report are: (1) Transform poplar and other tree species to extend and optimize chlorinated hydrocarbon (CHC) oxidative activities. (2) Determine the mechanisms of CHC oxidation in plants. (3) Isolate the genes responsible for CHC oxidation in plants. We have made significant progress toward an understanding of the biochemical mechanism of CHC transformation native to wild-type poplar. We have identified chloral, trichloroethanol, trichloroacetic acid, and dichloroacetic acid as products of TCE metabolism in poplar plants and in tissue cultures of poplar cells.(Newman et al. 1997; Newman et al. 1999) Use of radioactively labeled TCE showed that once taken up and transformed, most of the TCE was incorporated into plant tissue as a non-volatile, unextractable residue.(Shang et al. 2001; Shang and Gordon 2002) An assay for this transformation was developed and validated using TCE transformation by poplar suspension cells. Using this assay, it was shown that two different activities contribute to the fixation of TCE by poplar cells: one associated with cell walls and insoluble residues, the other associated with a high molecular weight, heat labile fraction of the cell extract, a fixation that was apparently catalyzed by plant enzymes.

  5. Distribution of multi-component solvents in solvent vapor extraction chamber

    Energy Technology Data Exchange (ETDEWEB)

    Das, S. [Society of Petroleum Engineers, Richardson, TX (United States)]|[Marathon Oil Corp., Houston, TX (United States)

    2008-10-15

    Vapex process performance is sensitive to operating pressures, temperatures and the types of solvent used. The hydrocarbon solvents used in Vapex processes typically have between 5 and 10 per cent hydrocarbon impurities, and the accumulation of dense phases inside the vapor chamber reduces gravity drainage potential. This study investigated the partitioning of solvent compounds inside the vapor chamber during in situ Vapex processes.The aim of the study was to examine how the different components of the mixed solvent partitioned inside the extracted chamber during the oil and vapor phase. A 2-D homogenous reservoir model was used to simulate the Vapex process with a solvent mixture comprised of propane and methane at various percentages. The effect of injecting a hot solvent vapor was also investigated. The study showed that injected methane accumulated at both the top and the extraction interface. Accumulations near the top had a positive impact on solvent confinement in thin reservoirs. Diffusion of the solvent component was controlled by gas phase molecular diffusion, and was much faster than the diffusion of solvent molecules in the liquid phase. The use of hot solvent mixtures slowed the extraction process due to lower solvent solubility in the oil phase. It was concluded that the negative impact on viscosity reduction by dilution was not compensated by rises in temperature. 6 refs., 11 figs.

  6. 40 CFR Table 6 to Subpart Qqqq of... - Default Organic HAP Mass Fraction for Petroleum Solvent Groups a

    Science.gov (United States)

    2010-07-01

    ... Spirits 150 EC, Naphtha, Mixed Hydrocarbon, Aliphatic Hydrocarbon, Aliphatic Naphtha, Naphthol Spirits, Petroleum Spirits, Petroleum Oil, Petroleum Naphtha, Solvent Naphtha, Solvent Blend. c E.g., Medium-flash Naphtha, High-flash Naphtha, Aromatic Naphtha, Light Aromatic Naphtha, Light Aromatic Hydrocarbons...

  7. 40 CFR Table 4 to Subpart Nnnn of... - Default Organic HAP Mass Fraction for Petroleum Solvent Groups a

    Science.gov (United States)

    2010-07-01

    ... Spirits 150 EC, Naphtha, Mixed Hydrocarbon, Aliphatic Hydrocarbon, Aliphatic Naphtha, Naphthol Spirits, Petroleum Spirits, Petroleum Oil, Petroleum Naphtha, Solvent Naphtha, Solvent Blend. c e.g., Medium-flash Naphtha, High-flash Naphtha, Aromatic Naphtha, Light Aromatic Naphtha, Light Aromatic Hydrocarbons...

  8. 40 CFR Table 4 to Subpart Rrrr of... - Default Organic HAP Mass Fraction for Petroleum Solvent Groups 1

    Science.gov (United States)

    2010-07-01

    ... EC, Naphtha, Mixed Hydrocarbon, Aliphatic Hydrocarbon, Aliphatic Naphtha, Naphthol Spirits, Petroleum Spirits, Petroleum Oil, Petroleum Naphtha, Solvent Naphtha, Solvent Blend. 3 E.g., Medium-flash Naphtha, High-flash Naphtha, Aromatic Naphtha, Light Aromatic Naphtha, Light Aromatic Hydrocarbons, Aromatic...

  9. Occupational exposure to solvents and bladder cancer

    DEFF Research Database (Denmark)

    Hadkhale, Kishor; Martinsen, Jan Ivar; Weiderpass, Elisabete;

    2017-01-01

    logistic regression model was used to estimate hazard ratios (HR) and their 95% confidence intervals (95% CI). Increased risks were observed for trichloroethylene (HR 1.23, 95% 95% CI 1.12-1.40), toluene (HR 1.20, 95% CI 1.00-1.38), benzene (HR 1.16, 95% CI 1.04-1.31), aromatic hydrocarbon solvents (HR 1...... of occupational exposure to trichloroethylene, perchloroethylene, aromatic hydrocarbon solvents, benzene and toluene and the risk of bladder cancer. This article is protected by copyright. All rights reserved....

  10. 40 CFR Table 6 to Subpart Vvvv of... - Default Organic HAP Contents of Petroleum Solvent Groups

    Science.gov (United States)

    2010-07-01

    ... Spirits 150 EC, Naphtha, Mixed Hydrocarbon, Aliphatic Hydrocarbon, Aliphatic Naptha, Naphthol Spirits, Petroleum Spirits, Petroleum Oil, Petroleum Naphtha, Solvent Naphtha, Solvent Blend.) 3 1% Xylene, 1% Toluene, and 1% Ethylbenzene. Aromatic (Medium-flash Naphtha, High-flash Naphtha, Aromatic Naphtha, Light...

  11. DOE solvent handbook information sheet

    Energy Technology Data Exchange (ETDEWEB)

    Chavez, A.A.

    1992-01-01

    Solvents and cleaners are used in the Department of Defense (DOD) and the Department of Energy-Defense Program (DOE-DP) maintenance facilities for removing wax, grease, oil, carbon, machining fluids, solder fluxes, mold releases, and other contaminants before repairing or electroplating parts. Private industry also uses cleaners and degreasers for surface preparation of various metals. Growing environmental and worker safety concerns have brought attention to these solvents and cleaners, most of which are classified as toxic. Tightening government regulations have already excluded the use of some chemicals, and restrict the use of various halogenated hydrocarbons because of their atmospheric-ozone depleting effects, as well as their cancer-related risks. As a result, a program was established to develop an efficient, easily accessible, electronic solvent utilization handbook. This is being accomplished by: (1) identifying solvents (alternatives) that are not currently restricted by government regulations for use DOE-DP facilities, and private industry, (2) evaluating their cleaning performance, (3) evaluating their corrosivity, (4) evaluating their air emissions, (5) evaluating the possibility of recycling or recovering all or portions of the alternative degreasers, (6) testing substitute solvents compatibility with non-metallic materials, (7) inputting all of the data gathered (including previous biodegradability information) into a database, and (8) developing a methodology for efficient, widespread access to the data base information system.

  12. DOE solvent handbook information sheet

    Energy Technology Data Exchange (ETDEWEB)

    Chavez, A.A.

    1992-05-01

    Solvents and cleaners are used in the Department of Defense (DOD) and the Department of Energy-Defense Program (DOE-DP) maintenance facilities for removing wax, grease, oil, carbon, machining fluids, solder fluxes, mold releases, and other contaminants before repairing or electroplating parts. Private industry also uses cleaners and degreasers for surface preparation of various metals. Growing environmental and worker safety concerns have brought attention to these solvents and cleaners, most of which are classified as toxic. Tightening government regulations have already excluded the use of some chemicals, and restrict the use of various halogenated hydrocarbons because of their atmospheric-ozone depleting effects, as well as their cancer-related risks. As a result, a program was established to develop an efficient, easily accessible, electronic solvent utilization handbook. This is being accomplished by: (1) identifying solvents (alternatives) that are not currently restricted by government regulations for use DOE-DP facilities, and private industry, (2) evaluating their cleaning performance, (3) evaluating their corrosivity, (4) evaluating their air emissions, (5) evaluating the possibility of recycling or recovering all or portions of the alternative degreasers, (6) testing substitute solvents compatibility with non-metallic materials, (7) inputting all of the data gathered (including previous biodegradability information) into a database, and (8) developing a methodology for efficient, widespread access to the data base information system.

  13. Experimental investigation of HFC407C/HC290/HC600a mixture in a window air conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Jabaraj, D.B.; Avinash, P.; Lal, D. Mohan; Renganarayan, S. [Department of Mechanical Engineering, College of Engineering, Anna University, Chennai 600 025 (India)

    2006-09-15

    HCFC22, one of the widely used refrigerants in window air conditioners must be phased out soon as per the Montreal protocol. Presently, HFC407C is considered as a potential drop in substitute for HCFC22, but retrofitting HCFC22 systems with HFC407C with polyol ester oil (POE) is a major issue as HFC407C is immiscible with mineral oil. The miscibility issue of HFC407C with mineral oil was overcome with the addition of a HC blend to it. The above technoeconomic feasibility issues to retrofit the existing HCFC22 systems with an ozone friendly refrigerant and retain the energy efficiency of the system are challenges in the air conditioning sector. In this present work, an experimental analysis has been conducted in a window air conditioner retrofitted with eco-friendly refrigerant mixtures of HFC407C/HC290/HC600a without changing the mineral oil. Its performance, as well as energy consumption, was compared with the conventional one. It is observed that the mixtures demand lengthening of the condenser in order to maintain the discharge pressure within acceptable limits. This also resulted in better heat transfer at the condenser. Therefore, in this study, the condenser tube length was increased by 19% to suit the mixtures as compared to HCFC22. Compared to HCFC22, the refrigeration capacity of the new mixture was 9.54-12.76% higher than that of HCFC22, while the actual COP was found to be 11.91-13.24% higher than that of HCFC22. The overall performance has proved that the HFC407C/HC blend refrigerant mixture could be an eco-friendly substitute to phase out HCFC22. (author)

  14. Characterization of hydrocarbon utilizing fungi from hydrocarbon ...

    African Journals Online (AJOL)

    Prof. Ogunji

    hydrocarbon polluted sediments and water .... ecosystem may result in selective increase or decrease in microbial population (Okpokwasili ... been implicated in degradation of hydrocarbons such as crude oil, polyaromatic hydrocarbons and.

  15. Global, Broad, or Specific Cognitive Differences? Using a MIMIC Model to Examine Differences in CHC Abilities in Children with Learning Disabilities

    Science.gov (United States)

    Niileksela, Christopher R.; Reynolds, Matthew R.

    2014-01-01

    This study was designed to better understand the relations between learning disabilities and different levels of latent cognitive abilities, including general intelligence (g), broad cognitive abilities, and specific abilities based on the Cattell-Horn-Carroll theory of intelligence (CHC theory). Data from the "Differential Ability…

  16. Comparing Models of Intelligence in Project TALENT: The VPR Model Fits Better than the CHC and Extended Gf-Gc Models

    Science.gov (United States)

    Major, Jason T.; Johnson, Wendy; Deary, Ian J.

    2012-01-01

    Three prominent theories of intelligence, the Cattell-Horn-Carroll (CHC), extended fluid-crystallized (Gf-Gc) and verbal-perceptual-image rotation (VPR) theories, provide differing descriptions of the structure of intelligence (McGrew, 2009; Horn & Blankson, 2005; Johnson & Bouchard, 2005b). To compare these theories, models representing them were…

  17. Methylenetetrahydrofolate reductase (MTHFR C677T polymorphism and high plasma homocysteine in chronic hepatitis C (CHC infected patients from the Northeast of Brazil

    Directory of Open Access Journals (Sweden)

    Silva Filipe

    2011-08-01

    Full Text Available Abstract Background/Aim Hyperhomocysteinemia due to Methylenetetrahydrofolate Reductase (MTHFR gene, in particular the C677T (Ala222Val polymorphism were recently associated to steatosis and fibrosis. We analyzed the frequency of MTHFR gene in a cross-sectional study of patients affected by Chronic Hepatitis C (CHC from Northeast of Brazil. Method One hundred seven-four untreated patients with CHC were genotyped for the C677T MTHFR. Genomic DNA was extracted from peripheral blood cells and the C677T MTHFR polymorphism was identified by PCR-RFLP. The homocysteine (Hcy levels were determined by chemiluminescence method. All patients were negative for markers of Wilson's disease, hemochromatosis and autoimmune diseases and have current and past daily alcohol intake less than 100 g/week. Results Among subjects infected with CHC genotype non-1 the frequency of MTHFR genotypes TT was 9.8% versus 4.4% genotype 1 (p = 0.01. Nevertheless, association was found between the MTHFR genotype TT × CT/CC polymorphism and the degree of steatosis and fibrosis in both hepatitis C genotype (p Conclusion Our results indicate that plasma Hcy levels is highly prevalent in subjects with chronic hepatits C with steatosis regardless of HCV genotype and vitamin deficiency. The presence of genotype TT of MTHFR C677T polymorphism was more common in CHC genotype non-1 infected patient regardless of histopathological classification and genotype TT+CT frequencies were significant in the presence of fibrosis grade 1+2 and of steatosis in CHC infected patients from the northeast of Brazil regardless of HCV genotype. The genetic susceptibility of MTHFR C677T polymorphism should be confirmed in a large population.

  18. Apparatus for hydrocarbon extraction

    Science.gov (United States)

    Bohnert, George W.; Verhulst, Galen G.

    2013-03-19

    Systems and methods for hydrocarbon extraction from hydrocarbon-containing material. Such systems and methods relate to extracting hydrocarbon from hydrocarbon-containing material employing a non-aqueous extractant. Additionally, such systems and methods relate to recovering and reusing non-aqueous extractant employed for extracting hydrocarbon from hydrocarbon-containing material.

  19. Dietary effects on cuticular hydrocarbons and sexual attractiveness in Drosophila.

    Directory of Open Access Journals (Sweden)

    Tatyana Y Fedina

    Full Text Available Dietary composition is known to have profound effects on many aspects of animal physiology, including lifespan, general health, and reproductive potential. We have previously shown that aging and insulin signaling significantly influence the composition and sexual attractiveness of Drosophila melanogaster female cuticular hydrocarbons (CHCs, some of which are known to be sex pheromones. Because diet is intimately linked to aging and to the activity of nutrient-sensing pathways, we asked how diet affects female CHCs and attractiveness. Here we report consistent and significant effects of diet composition on female CHC profiles across ages, with dietary yeast and sugar driving CHC changes in opposite directions. Surprisingly, however, we found no evidence that these changes affect female attractiveness. Multivariate comparisons among responses of CHC profiles to diet, aging, and insulin signaling suggest that diet may alter the levels of some CHCs in a way that results in profiles that are more attractive while simultaneously altering other CHCs in a way that makes them less attractive. For example, changes in short-chain CHCs induced by a high-yeast diet phenocopy changes caused by aging and by decreased insulin signaling, both of which result in less attractive females. On the other hand, changes in long-chain CHCs in response to the same diet result in levels that are comparable to those observed in attractive young females and females with increased insulin signaling. The effects of a high-sugar diet tend in the opposite direction, as levels of short-chain CHCs resemble those in attractive females with increased insulin signaling and changes in long-chain CHCs are similar to those caused by decreased insulin signaling. Together, these data suggest that diet-dependent changes in female CHCs may be sending conflicting messages to males.

  20. Cuticular hydrocarbons as a basis for chemosensory self-referencing in crickets: a potentially universal mechanism facilitating polyandry in insects.

    Science.gov (United States)

    Weddle, Carie B; Steiger, Sandra; Hamaker, Christopher G; Ower, Geoffrey D; Mitchell, Christopher; Sakaluk, Scott K; Hunt, John

    2013-03-01

    Females of many species obtain benefits by mating polyandrously, and often prefer novel males over previous mates. However, how do females recognise previous mates, particularly in the face of cognitive constraints? Female crickets appear to have evolved a simple but effective solution: females imbue males with their own cuticular hydrocarbons (CHCs) at mating and utilise chemosensory self-referencing to recognise recent mates. Female CHC profiles exhibited significant additive genetic variation, demonstrating that genetically unique chemical cues are available to support chemosensory self-referencing. CHC profiles of males became more similar to those of females after mating, indicating physical transfer of CHCs between individuals during copulation. Experimental perfuming of males with female CHCs resulted in a female aversion to males bearing chemical cues similar to their own. Chemosensory self-referencing, therefore, could be a widespread mechanism by which females increase the diversity of their mating partners. © 2012 Blackwell Publishing Ltd/CNRS.

  1. Isolation and determination of absolute configurations of insect-produced methyl-branched hydrocarbons.

    Science.gov (United States)

    Bello, Jan E; McElfresh, J Steven; Millar, Jocelyn G

    2015-01-27

    Although the effects of stereochemistry have been studied extensively for volatile insect pheromones, little is known about the effects of chirality in the nonvolatile methyl-branched hydrocarbons (MBCHs) used by many insects as contact pheromones. MBCHs generally contain one or more chiral centers and so two or more stereoisomeric forms are possible for each structure. However, it is not known whether insects biosynthesize these molecules in high stereoisomeric purity, nor is it known whether insects can distinguish the different stereoisomeric forms of MBCHs. This knowledge gap is due in part to the lack of methods for isolating individual MBCHs from the complex cuticular hydrocarbon (CHC) blends of insects, as well as the difficulty in determining the absolute configurations of the isolated MBCHs. To address these deficiencies, we report a straightforward method for the isolation of individual cuticular hydrocarbons from the complex CHC blend. The method was used to isolate 36 pure MBCHs from 20 species in nine insect orders. The absolute stereochemistries of the purified MBCHs then were determined by digital polarimetry. The absolute configurations of all of the isolated MBCHs were determined to be (R) by comparison with a library of synthesized, enantiomerically pure standards, suggesting that the biosynthetic pathways used to construct MBCHs are highly conserved within the Insecta. The development of a straightforward method for isolation of specific CHCs will enable determination of their functional roles by providing pure compounds for bioassays.

  2. Post-mating shift towards longer-chain cuticular hydrocarbons drastically reduces female attractiveness to males in a digger wasp.

    Science.gov (United States)

    Polidori, Carlo; Giordani, Irene; Wurdack, Mareike; Tormos, José; Asís, Josep D; Schmitt, Thomas

    2017-07-01

    Females of most aculeate Hymenoptera mate only once and males are therefore under a strong competitive pressure which is expected to favour the evolution of rapid detection of virgin females. In several bee species, the cuticular hydrocarbon (CHC) profile exhibited by virgin females elicits male copulation attempts. However, it is still unknown how widespread this type of sexual communication is within Aculeata. Here, we investigated the use of CHCs as mating cues in the digger wasp Stizus continuus, which belongs to the family (Crabronidae) from within bees arose. In field experiments, unmanipulated, recently emerged virgin female dummies promptly elicit male copulation attempts, whereas 1-4days old mated females dummies were still attractive but to a much lesser extent. In contrast, old (10-15days) mated female dummies did not attract males at all. After hexane-washing, attractiveness almost disappeared but could be achieved by adding CHC extracts from virgin females even on hexane-washed old mated females. Thus, the chemical base of recognition of females as appropriate mating partner by males is coded in their CHC profile. Accordingly, differences in CHC profiles can be detected between sexes, with males having larger amounts of alkenes and exclusive long-chain alkanes, and within females specially according to their mating status. Shortly after mating, almost all of the major hydrocarbons found on the cuticle of females undergo significant changes in their abundance, with a clear shift from short-chain to long-chain linear and methyl-branched alkanes. The timely detection of virgin females by males in S. continuus could be advantageous within the narrow period of female emergence, when male-male competition is strongest. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. 40 CFR Table 4 to Subpart IIIi of... - Default Organic HAP Mass Fraction for Petroleum Solvent Groups a

    Science.gov (United States)

    2010-07-01

    ..., Mineral Spirits 150 EC, Naphtha, Mixed Hydrocarbon, Aliphatic Hydrocarbon, Aliphatic Naphtha, Naphthol Spirits, Petroleum Spirits, Petroleum Oil, Petroleum Naphtha, Solvent Naphtha, Solvent Blend. c E.g., Medium-flash Naphtha, High-flash Naphtha, Aromatic Naphtha, Light Aromatic Naphtha, Light Aromatic...

  4. 40 CFR Table 4 to Subpart Pppp of... - Default Organic HAP Mass Fraction for Petroleum Solvent Groups a

    Science.gov (United States)

    2010-07-01

    ... aromatic. b Mineral Spirits 135, Mineral Spirits 150 EC, Naphtha, Mixed Hydrocarbon, Aliphatic Hydrocarbon, Aliphatic Naphtha, Naphthol Spirits, Petroleum Spirits, Petroleum Oil, Petroleum Naphtha, Solvent Naphtha, Solvent Blend. c Medium-flash Naphtha, High-flash Naphtha, Aromatic Naphtha, Light Aromatic Naphtha, Light...

  5. 40 CFR Table 4 to Subpart Mmmm of... - Default Organic HAP Mass Fraction for Petroleum Solvent Groups a

    Science.gov (United States)

    2010-07-01

    ... aliphatic or aromatic. b Mineral Spirits 135, Mineral Spirits 150 EC, Naphtha, Mixed Hydrocarbon, Aliphatic Hydrocarbon, Aliphatic Naphtha, Naphthol Spirits, Petroleum Spirits, Petroleum Oil, Petroleum Naphtha, Solvent Naphtha, Solvent Blend. c Medium-flash Naphtha, High-flash Naphtha, Aromatic Naphtha, Light Aromatic...

  6. Carcinoma hepatocelular (CHC. Factores de riesgo, diagnóstico y tratamiento. Hospital Pablo Tobón Uribe, 1995-2000

    Directory of Open Access Journals (Sweden)

    Gonzálo Correa Arango

    2001-04-01

    Full Text Available

    Por estudios epidemiológicos sabemos que el CHC es el octavo
    cáncer más frecuente en el mundo; también que es 3 veces más
    frecuente en hombres que en mujeres tanto en el mundo como en
    Antioquia (1,2 y que se presentan 350.000 casos nuevos cada año.
    Nuestro objetivo es describir el comportamiento clínico y epidemiológico del CHC en la población usuaria del HPTU entre enero de 1995 y julio del 2000.

     

     

  7. Otoneurologic disturbances caused by solvent pollution.

    Science.gov (United States)

    Odkvist, L M; Möller, C; Thuomas, K A

    1992-06-01

    Subjects exposed to industrial solvents may experience vertigo and nausea. Solvents are usually volatile hydrocarbon compounds, which are important parts of everyday life in a modern society. They may also cause neurastenia, personality changes, and reduced intellectual capacity. The syndrome that may develop was formerly named psycho-organic syndrome (POS), but in modern terminology it is called chronic toxic encephalopathy (CTE). The syndrome develops slowly, and during the first years no pathological findings will be found using various test batteries. Somewhat later, when the syndrome still might be reversible, psychometric, auditory, and otoneurologic testing may well unveil disturbances within the posterior fossa structures. Animal experiments suggest one site of effect for solvents to be within the cerebellum and brainstem regions with close relationship to the gamma-amino-butyric acid (GABA) transmission. In the otoneurologic test battery, visual suppression and smooth pursuit are of extreme value, as are some auditory tests such as discrimination of interrupted speech and cortical response audiometry using frequency glides as stimuli. Dynamic posturography and magnetic resonance imaging (MRI) have recently proved valuable in the diagnosis. Research is needed concerning the most efficient test battery for early detection of solvent-induced lesions. During further research it is important to unveil other toxic agents, like heavy metals and alcohol, and their damage to the central nervous system and to make comparisons between these substances and the lesions caused by hydrocarbon solvents.

  8. Study of General Awareness, Attitude, Behavior, and Practice Study on Dog Bites and its Management in the Context of Prevention of Rabies Among the Victims of Dog Bite Attending the OPD Services of CHC Muradnagar

    OpenAIRE

    Jain, Piyush; Jain, Garima

    2014-01-01

    Objectives: This is a recent study conducted during 15th September 2013 to 15th December 2013 at the community health centre (CHC), Muradnagar, distt Ghaziabad, among the victims of dog/animal bite attending the daily OPD services of CHC. To identify the level of general awareness and knowledge of wound management and rabies among the cases of dog bite and to study the awareness of people about antirabies vaccines and health service utilization. Methods: The study population composed of 250 v...

  9. A silica gel based method for extracting insect surface hydrocarbons.

    Science.gov (United States)

    Choe, Dong-Hwan; Ramírez, Santiago R; Tsutsui, Neil D

    2012-02-01

    Here, we describe a novel method for the extraction of insect cuticular hydrocarbons using silica gel, herein referred to as "silica-rubbing". This method permits the selective sampling of external hydrocarbons from insect cuticle surfaces for subsequent analysis using gas chromatography-mass spectrometry (GC-MS). The cuticular hydrocarbons are first adsorbed to silica gel particles by rubbing the cuticle of insect specimens with the materials, and then are subsequently eluted using organic solvents. We compared the cuticular hydrocarbon profiles that resulted from extractions using silica-rubbing and solvent-soaking methods in four ant and one bee species: Linepithema humile, Azteca instabilis, Camponotus floridanus, Pogonomyrmex barbatus (Hymenoptera: Formicidae), and Euglossa dilemma (Hymenoptera: Apidae). We also compared the hydrocarbon profiles of Euglossa dilemma obtained via silica-rubbing and solid phase microextraction (SPME). Comparison of hydrocarbon profiles obtained by different extraction methods indicates that silica rubbing selectively extracts the hydrocarbons that are present on the surface of the cuticular wax layer, without extracting hydrocarbons from internal glands and tissues. Due to its surface specificity, efficiency, and low cost, this new method may be useful for studying the biology of insect cuticular hydrocarbons.

  10. The hydrocarbon sphere

    Energy Technology Data Exchange (ETDEWEB)

    Mandev, P.

    1984-01-01

    The hydrocarbon sphere is understood to be the area in which hydrocarbon compounds are available. It is believed that the lower boundary on the hydrocarbon sphere is most probably located at a depth where the predominant temperatures aid in the destruction of hydrocarbons (300 to 400 degrees centigrade). The upper limit on the hydrocarbon sphere obviously occurs at the earth's surface, where hydrocarbons oxidize to H20 and CO2. Within these ranges, the occurrence of the hydrocarbon sphere may vary from the first few hundred meters to 15 kilometers or more. The hydrocarbon sphere is divided into the external (mantle) sphere in which the primary gas, oil and solid hydrocarbon fields are located, and the internal (metamorphic) sphere containing primarily noncommercial accumulations of hydrocarbon gases and solid carbon containing compounds (anthraxilite, shungite, graphite, etc.) based on the nature and scale of hydrocarbon compound concentrations (natural gas, oil, maltha, asphalt, asphaltite, etc.).

  11. Divergence of cuticular hydrocarbons in two sympatric grasshopper species and the evolution of fatty acid synthases and elongases across insects

    Science.gov (United States)

    Finck, Jonas; Berdan, Emma L.; Mayer, Frieder; Ronacher, Bernhard; Geiselhardt, Sven

    2016-01-01

    Cuticular hydrocarbons (CHCs) play a major role in the evolution of reproductive isolation between insect species. The CHC profiles of two closely related sympatric grasshopper species, Chorthippus biguttulus and C. mollis, differ mainly in the position of the first methyl group in major methyl-branched CHCs. The position of methyl branches is determined either by a fatty acid synthase (FAS) or by elongases. Both protein families showed an expansion in insects. Interestingly, the FAS family showed several lineage-specific expansions, especially in insect orders with highly diverse methyl-branched CHC profiles. We found five putative FASs and 12 putative elongases in the reference transcriptomes for both species. A dN/dS test showed no evidence for positive selection acting on FASs and elongases in these grasshoppers. However, one candidate FAS showed species-specific transcriptional differences and may contribute to the shift of the methyl-branch position between the species. In addition, transcript levels of four elongases were expressed differentially between the sexes. Our study indicates that complex methyl-branched CHC profiles are linked to an expansion of FASs genes, but that species differences can also mediated at the transcriptional level. PMID:27677406

  12. Synergistic degradation of chlorinated hydrocarbons with microorganisms and zero valent iron

    Science.gov (United States)

    Schöftner, Philipp; Summer, Dorothea; Leitner, Simon; Watzinger, Andrea; Wimmer, Bernhard; Reichenauer, Thomas

    2016-04-01

    Sites contaminated with chlorinated hydrocarbons (CHC) are located mainly within build-up regions. Therefore in most cases only in-situ technologies without excavation of soil material can be used for remediation. This project examines a novel in-situ remediation method, in which the biotic degradation via bacteria is combined with abiotic degradation via zero-valent iron particles (ZVI). ZVI particles are injected into the aquifer where CHC-molecules are reductively dechlorinated. However Fe0 is also oxidized by reaction with water leading to generation of H2 without any CHC degradation. To achieve biotic degradation often strictly anaerobic strains of the bacteria Dehalococcoides are used. These bacteria can dechlorinate CHC by utilizing H2. By combining these processes the H2, produced during the anaerobic corrosion of Fe0, could be used by bacteria for further CHC degradation. Therefore the amount of used Fe0 and as a consequence also remediation costs could be reduced. Additionally the continuous supply of H2 could make the bacterial degradation more controllable. Different Fe0 particles (nano- and micro-scale) were tested for their perchloroethene (PCE) degradation rate and H2 production rate in microcosms. PCE-degradation rate by different bacterial cultures was investigated in the same microcosm system. In course of these experiments the 13C enrichment factors of the PCE degradation of the different particles and cultures were determined to enable the differentiation of biotic and abiotic degradation. Preliminary results showed, that the nano-scale particles reacted faster with PCE and water than their micro-scaled counterparts. The PCE degradation via micro-scaled particles lead to 13C enrichment factors in the range of -3,6 ‰ ± 0,6 to -9,5 ‰ ± 0,2. With one of the examined bacterial cultures a fast reduction of PCE to ethene was observed. Although PCE and TCE were completely degraded by this culture the metabolites DCE and VC could still be detected

  13. Raman characteristics of hydrocarbon and hydrocarbon inclusions

    Institute of Scientific and Technical Information of China (English)

    ZHANG Nai; TIAN ZuoJi; LENG YingYing; WANG HuiTong; SONG FuQing; MENG JianHua

    2007-01-01

    The Raman spectrograms of hydrocarbon standard samples show that: (1) the Raman spectrogram of normal paraffin has very strong peaks of methyl and methylene (from 2700 cm-1 to 2970 cm-1); (2)branch methyl has the particular peak of 748 cm-1±; (3) six cyclic has the particular peak of 804 cm-1±; (4)phenyl has two particular peaks of 988 cm-1± and 3058 cm-1± and the 988 cm-1± peak is stronger than the 3058 cm-1± peak; and (5) hexene has three alkenyl spectrum peaks of 1294 cm-1±, 1635 cm-1± and 2996 cm-1±, with the 1635 cm-1± peak being the strongest, showing that the number of carbon in hydrocarbon does not affect its Raman spectrogram, and the hydrocarbon molecular structure and base groups affect its Raman spectrogram, the same hydrocarbons (such as normal paraffin) have the same Raman spectrogram; the types (such as CH4, C2H6, C3H8) and the content of hydrocarbon in oil inclusions are not estimated by their characteristic Raman peaks. According to the Raman spectrograms of hydrocarbon compositions, the Raman spectrogram of hydrocarbon inclusion can be divided into five types: saturated hydrocarbon Raman spectrogram, fluoresce Raman spectrogram, saturated hydrocarbon bitumen Raman spectrogram, bitumen Raman spectrogram, and ethane Raman spectrogram.And according to the characteristics of Raman spectrogram, hydrocarbon inclusions can be divided into five types: saturated hydrocarbon inclusion, less saturated hydrocarbon (oil or gas) inclusion,saturated hydrocarbon bitumen inclusion, bitumen inclusion, and methane water inclusion.

  14. Raman characteristics of hydrocarbon and hydrocarbon inclusions

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Raman spectrograms of hydrocarbon standard samples show that: (1) the Raman spectrogram of normal paraffin has very strong peaks of methyl and methylene (from 2700 cm-1 to 2970 cm-1); (2) branch methyl has the particular peak of 748 cm-1±; (3) six cyclic has the particular peak of 804 cm-1±; (4) phenyl has two particular peaks of 988 cm-1± and 3058 cm-1± and the 988 cm-1± peak is stronger than the 3058 cm-1± peak; and (5) hexene has three alkenyl spectrum peaks of 1294 cm-1±, 1635 cm-1± and 2996 cm-1±, with the 1635 cm-1± peak being the strongest, showing that the number of carbon in hy-drocarbon does not affect its Raman spectrogram, and the hydrocarbon molecular structure and base groups affect its Raman spectrogram, the same hydrocarbons (such as normal paraffin) have the same Raman spectrogram; the types (such as CH4, C2H6, C3H8) and the content of hydrocarbon in oil inclu-sions are not estimated by their characteristic Raman peaks. According to the Raman spectrograms of hydrocarbon compositions, the Raman spectrogram of hydrocarbon inclusion can be divided into five types: saturated hydrocarbon Raman spectrogram, fluoresce Raman spectrogram, saturated hydro-carbon bitumen Raman spectrogram, bitumen Raman spectrogram, and ethane Raman spectrogram. And according to the characteristics of Raman spectrogram, hydrocarbon inclusions can be divided into five types: saturated hydrocarbon inclusion, less saturated hydrocarbon (oil or gas) inclusion, saturated hydrocarbon bitumen inclusion, bitumen inclusion, and methane water inclusion.

  15. Solvent resistant nanofiltration membranes

    OpenAIRE

    Dutczak, S.M.

    2011-01-01

    This thesis describes preparation and characterization of membranes for organic solvent filtration (OSF). The main aim was developing membranes for solvent resistant nanofiltration (SRNF) with molecular weight cut-off below 500 g mol-1.

  16. Solvents in novolak synthesis

    Science.gov (United States)

    Sobodacha, Chet J.; Lynch, Thomas J.; Durham, Dana L.; Paradis, Valerie R.

    1993-09-01

    Novolac resins may be prepared with or without a solvent present. We have found that solvent power greatly affects the properties of the finished resin and thus gives the resist chemist another variable with which to `fine-tune' resist properties. Using designed experiments, we investigated the effect of solvent power, as measured by Hansen's Solubility Parameters, of a number of solvents and solvent mixtures on the final properties of the novolac resin. We found that the relative molecular weight (RMW) and dissolution rate of a novolac resin can be varied by selection of a solvent or solvent mixture with the appropriate polarity and hydrogen- bonding characteristics. The solvent polarity and hydrogen-bonding characteristics may affect the stability of the cresol/formaldehyde transition state, thus causing the observed changes in RMW and dissolution rate.

  17. Method for determining asphaltene stability of a hydrocarbon-containing material

    Science.gov (United States)

    Schabron, John F; Rovani, Jr., Joseph F

    2013-02-05

    A method for determining asphaltene stability in a hydrocarbon-containing material having solvated asphaltenes therein is disclosed. In at least one embodiment, it involves the steps of: (a) precipitating an amount of the asphaltenes from a liquid sample of the hydrocarbon-containing material with an alkane mobile phase solvent in a column; (b) dissolving a first amount and a second amount of the precipitated asphaltenes by changing the alkane mobile phase solvent to a final mobile phase solvent having a solubility parameter that is higher than the alkane mobile phase solvent; (c) monitoring the concentration of eluted fractions from the column; (d) creating a solubility profile of the dissolved asphaltenes in the hydrocarbon-containing material; and (e) determining one or more asphaltene stability parameters of the hydrocarbon-containing material.

  18. Catalytic hydrogen-chlorine exchange between chlorinated hydrocarbons under oxygen-free conditions

    NARCIS (Netherlands)

    van der Heijden, A.W.A.M.; Podkolzin, S.G.; Jones, M.E.; Bitter, J.H.; Weckhuysen, B.M.

    2008-01-01

    Chlorinated hydrocarbons (CHCs) remain important industrial chemical intermediates and solvents, especially for the exploration of the potential of La-based materials for the conversion of chlorinated waste compounds.[1] The production of industrially important CHCs frequently occurs with concurrent

  19. How Can We Use Carbon Dioxide as a Solvent?

    Science.gov (United States)

    Mohamed, Azmi; Eastoe, Julian

    2011-01-01

    This article describes the work being undertaken to make more use of supercritical carbon dioxide as a green solvent. It discusses how the use of surfactants can address the limitations of supercritical CO[subscript 2] in dissolving solutes that are polar and of higher molecular weight. The design of appropriate hydrocarbon CO[subscript 2]-philic…

  20. Solvent abuse: a review.

    Science.gov (United States)

    Barnes, G E

    1979-01-01

    The literature on solvent abuse is reviewed. Methods of use, symptoms of use, and effects of long-term solvent abuse are discussed. Several surveys on solvent use are summarized. The highest prevalence of solvent abuse seems to occur in native peoples undergoing periods of cultural change. Environmental conditions which are postulated as leading to psychological vulnerability and solvent abuse include: low social assets, parental drug use, peer and sibling influence, and acculturative stress. Solvent abuse seems to provide a pharmacological way out of a stressful environment for people who feel helpless to improve their situation in other ways. Methods of intervention that have been proposed for dealing with solvent abuse are discussed. Methods of intervention thus far employed generally have not been evaluated in any systematic fashion. Suggestions for future research are provided.

  1. The reaction of the acrylonitrile ion CH 2dbnd CH-C tbnd N rad + with HCN: Proton-transport catalysis vs formation of ionized pyrimidine

    Science.gov (United States)

    Ervasti, Henri K.; Jobst, Karl J.; Gerbaux, Pascal; Burgers, Peter C.; Ruttink, Paul J. A.; Terlouw, Johan K.

    2009-11-01

    The CBS-QB3 model chemistry predicts that the title ion-molecule reaction, of potential interest in astrochemistry, yields a stable head-to-tail dimer, [HC dbnd N-CH 2C(H)C tbnd N] rad + ( D1). Cyclization of D1 into ionized pyrimidine seems possible, but the initiating 1,2-H shift is close in energy to back-dissociation into CH 2dbnd C(H)CN rad + ( AN) + HCN. Less energy demanding is formation of the H-bridged isomers [CH 2dbnd C(CN)H--N tbnd CH] rad + and [HC tbnd N--HC(H) dbnd C(H)CN] rad +, whose HCN component may catalyze isomerization of AN into CH 2dbnd C dbnd C dbnd NH rad + ( AN1) and CH dbnd C(H)C dbnd NH rad + ( AN2) respectively. Tandem mass spectrometry based experiments using 15N/ 13C labelling show that cyclization of D1 does not occur and that AN1 is the predominant reaction product instead.

  2. Hydrogenation of Isophthalonitrile with 1-Methylimidazole as an Effective Solvent for m-Xylenediamine Production

    Energy Technology Data Exchange (ETDEWEB)

    Chae, Tae Young; Row, Sung Wook; Yoo, Kye Sang; Lee, Sang Duek [Environment and Process Technology Division, Seoul (Korea, Republic of); Lee, Do Weon [University of Seoul, Seoul (Korea, Republic of)

    2006-03-15

    1-methylimidazole was shown to outperform the other organic solvents in this reaction. Moreover, amount of ammonia with using 1-methylimidazole as a solvent was lower than other processes. Thus, 1-methylimidazole is an attractive solvent in IPN hydrogenation for the production of MXDA. The correct choice of a solvent is a critical factor to govern the catalytic activity with desirable hydrogenation. Conventionally, organic materials such as aromatic hydrocarbons, aliphatic alcohols, aliphatic hydrocarbons, dimethylformamide and dioxane were employed in this reaction. Several MXDA producing processes with the organic solvent including m-xylene, pseudocumene, mesitylene, ethylbenzene, methylpyridine, benzonitrile, m-tolunitrile, MXDA and cyanopyridine were disclosed. However, the solvents and ammonia were vaporized under the operation conditions leading to amine cleavage with the resulting formation of methylbenzyl amines or the consumption of ammonia was still significant. Recently, some researchers reported that a high yield of MXDA was achieved using isopropanol under relatively low pressure condition; however, the consumption of ammonia was very significant.

  3. Cuticular hydrocarbons of Drosophila montana: geographic variation, sexual dimorphism and potential roles as pheromones.

    Science.gov (United States)

    Jennings, Jackson H; Etges, William J; Schmitt, Thomas; Hoikkala, Anneli

    2014-02-01

    Sexual selection within populations can play an important role in speciation when divergence in mating signals and their corresponding preferences occur along different coevolutionary trajectories in different populations. In insects, one potential target of sexual selection is the blend of cuticular hydrocarbons (CHCs), which often show intra- and interspecific variation, sexual dimorphism and may act as pheromones. In Drosophila montana, a cold-adapted, circumboreal member of the Drosophila virilis species group, flies from different populations have been found to show significant premating isolation as well as variation in male mating signal (song) and female preference. While the role of male courtship song in mate choice has been studied extensively, CHCs in this species have received little attention. In this study, we identified most of the CHCs found on the cuticle of D. montana and characterized population divergence and sexual dimorphism of CHC profiles among flies established from three natural populations - one European and two North American. We also studied their potential role as pheromones by analyzing CHCs of flies used in female-choice mating experiments. We report significant population×sex effects on CHC profiles, as well as significant relationships between some CHC principal components and particular mating behaviours, such as female attractiveness and male mating success, providing evidence that CHCs may play a role in mate choice in this species. The study also provides evidence for variation in the degree to which CHCs play a role in chemical communication among these populations, which may have an influence on the speciation process itself, and could be due to variation in interactions with other closely-related species that occur sympatrically with D. montana in some, but not other, parts of its distribution. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Influence of Solvent-Solvent and Solute-Solvent Interaction Properties on Solvent-Mediated Potential

    Institute of Scientific and Technical Information of China (English)

    ZHOU Shi-Qi

    2005-01-01

    A recently proposed universal calculational recipe for solvent-mediated potential is applied to calculate excess potential of mean force between two large Lennard-Jones (LJ) or hard core attractive Yukawa particles immersed in small LJ solvent bath at supercritical state. Comparison between the present prediction with a hypernetted chain approximation adopted for solute-solute correlation at infinitely dilute limit and existing simulation data shows high accuracy for the region with large separation, and qualitative reliability for the solute particle contact region. The calculational simplicity of the present recipe allows for a detailed investigation on the effect of the solute-solvent and solvent-solvent interaction details on the excess potential of mean force. The resultant conclusion is that gathering of solvent particles near a solute particle leads to repulsive excess PMF, while depletion of solvent particles away from the solute particle leads to attractive excess PMF, and minor change of the solvent-solvent interaction range has large influence on the excess PMF.

  5. Porphyrin-Embedded Silicate Materials for Detection of Hydrocarbon Solvents

    Science.gov (United States)

    2011-01-14

    are naturally occurring in petroleum products . The individual compounds are also used in a range of manufacturing and production processes. The BTEX...478-483. 17. Ueno, Y.; Tate, A.; Niwa, O.; Zhou, H.-S.; Yamada, T.; Honma, I. High benzene selectivity of mesoporous silicate for BTX gas sensing

  6. Extraction Techniques for Polycyclic Aromatic Hydrocarbons in Soils

    Directory of Open Access Journals (Sweden)

    E. V. Lau

    2010-01-01

    Full Text Available This paper aims to provide a review of the analytical extraction techniques for polycyclic aromatic hydrocarbons (PAHs in soils. The extraction technologies described here include Soxhlet extraction, ultrasonic and mechanical agitation, accelerated solvent extraction, supercritical and subcritical fluid extraction, microwave-assisted extraction, solid phase extraction and microextraction, thermal desorption and flash pyrolysis, as well as fluidised-bed extraction. The influencing factors in the extraction of PAHs from soil such as temperature, type of solvent, soil moisture, and other soil characteristics are also discussed. The paper concludes with a review of the models used to describe the kinetics of PAH desorption from soils during solvent extraction.

  7. Solvent as a competitive inhibitor for Candida antarctica lipase B.

    Science.gov (United States)

    Graber, Marianne; Irague, Romain; Rosenfeld, Eric; Lamare, Sylvain; Franson, Linda; Hult, Karl

    2007-08-01

    In enzyme-catalyzed reactions, the choice of solvent often has a marked effect on the reaction outcome. In this paper, it is shown that solvent effects could be explained by the ability of the solvent to act as a competitive inhibitor to the substrate. Experimentally, the effect of six solvents, 2-pentanone, 3-pentanone, 2-methyl-2-pentanol, 3-methyl-3-pentanol, 2-methylpentane and 3-methylpentane, was studied in a solid/gas reactor. As a model reaction, the CALB-catalyzed transacylation between methyl propanoate and 1-propanol, was studied. It was shown that both ketones inhibited the enzyme activity whereas the tertiary alcohols and the hydrocarbons did not. Alcohol inhibition constants, K(i)(I) were changed to "K(i)", determined in presence of 2-pentanone, 3-pentanone, and 3-methyl-3-pentanol, confirmed the marked inhibitory character of the ketones and an absence of inhibition of 3-methyl-3-pentanol. The molecular modeling study was performed on three solvents, 2-pentanone, 2-methyl-2-pentanol and 2-methyl pentane. It showed a clear inhibitory effect for the ketone and the tertiary alcohol, but no effect for the hydrocarbon. No change in enzyme conformation was seen during the simulations. The study led to the conclusion that the effect of added organic component on lipase catalyzed transacylation could be explained by the competitive inhibitory character of solvents towards the first binding substrate methyl propanoate.

  8. Reactive Extraction of Alcohols from Apolar Hydrocarbons with Aqueous Solutions

    NARCIS (Netherlands)

    Kuzmanovic, B.; Kuipers, N.J.M.; de Haan, A.B.; Kwant, Gerard

    2006-01-01

    The aqueous solutions are evaluated as sustainable reactive extraction solvents for the recovery of monohydroxyl alcohols (benzyl alcohol, 1-hexanol, cyclohexanol) present in few-percent concentrations in apolar hydrocarbons (toluene, n-hexane, and cyclohexane) by considering two approaches. An aque

  9. Reactive Extraction of Alcohols from Apolar Hydrocarbons with Aqueous Solutions

    NARCIS (Netherlands)

    Kuzmanovic, Boris; Kuipers, Norbert J.M.; Haan, de André B.; Kwant, Gerard

    2006-01-01

    The aqueous solutions are evaluated as sustainable reactive extraction solvents for the recovery of monohydroxyl alcohols (benzyl alcohol, 1-hexanol, cyclohexanol) present in few-percent concentrations in apolar hydrocarbons (toluene, n-hexane, and cyclohexane) by considering two approaches. An aque

  10. Relationships between Cattell-Horn-Carroll (CHC) cognitive abilities and math achievement within a sample of college students with learning disabilities.

    Science.gov (United States)

    Proctor, Briley

    2012-01-01

    This study examined the relationship between cognitive abilities and math achievement within a sample of college students with learning disabilities (LD). The cognitive abilities were seven areas identified by Stratum II of the Cattell-Horn-Carroll (CHC) theory of cognitive abilities, in addition to the eighth area of Working Memory. Math performance was assessed via math calculation and math reasoning tasks. Instruments include the Woodcock-Johnson III Tests of Cognitive Abilities and Tests of Achievement. Participants were 158 college students with a diagnosed LD in math. Multiple regression analyses found that Processing Speed and Working Memory were related to Math Calculation scores and that Comprehension-Knowledge, Fluid Reasoning, and Working Memory were related to Math Reasoning. Implications for the assessment of math LD in the college populations are discussed.

  11. Green Solvents for Precision Cleaning

    Science.gov (United States)

    Grandelli, Heather; Maloney, Phillip; DeVor, Robert; Surma, Jan; Hintze, Paul

    2013-01-01

    Aerospace machinery used in liquid oxygen (LOX) fuel systems must be precision cleaned to achieve a very low level of non-volatile residue (< 1 mg0.1 m2), especially flammable residue. Traditionally chlorofluorocarbons (CFCs) have been used in the precision cleaning of LOX systems, specifically CFC 113 (C2Cl3F3). CFCs have been known to cause the depletion of ozone and in 1987, were banned by the Montreal Protocol due to health, safety and environmental concerns. This has now led to the development of new processes in the precision cleaning of aerospace components. An ideal solvent-replacement is non-flammable, environmentally benign, non-corrosive, inexpensive, effective and evaporates completely, leaving no residue. Highlighted is a green precision cleaning process, which is contaminant removal using supercritical carbon dioxide as the environmentally benign solvent. In this process, the contaminant is dissolved in carbon dioxide, and the parts are recovered at the end of the cleaning process completely dry and ready for use. Typical contaminants of aerospace components include hydrocarbon greases, hydraulic fluids, silicone fluids and greases, fluorocarbon fluids and greases and fingerprint oil. Metallic aerospace components range from small nuts and bolts to much larger parts, such as butterfly valves 18 in diameter. A fluorinated grease, Krytox, is investigated as a model contaminant in these preliminary studies, and aluminum coupons are employed as a model aerospace component. Preliminary studies are presented in which the experimental parameters are optimized for removal of Krytox from aluminum coupons in a stirred-batch process. The experimental conditions investigated are temperature, pressure, exposure time and impeller speed. Temperatures of 308 - 423 K, pressures in the range of 8.3 - 41.4 MPa, exposure times between 5 - 60 min and impeller speeds of 0 - 1000 rpm were investigated. Preliminary results showed up to 86 cleaning efficiency with the

  12. Spectrophotometric study of the charge transfer complexes of 4'-nitrobenzo-15-crown-5 and benzo-15-crown-5 with iodine in nonaqueous solvents

    Institute of Scientific and Technical Information of China (English)

    Nina Alizadeh; Sadegh Dehghanikhah

    2011-01-01

    The formation of charge transfer complex between iodine with 4'-nitrobenzo-15-crown-5 (NB15C5) and benzo-15-crown-5 (B15C5) is investigated spectrophotometrically in chloroform and dichloromethane (DCM) solutions at 25℃. The pseudo-first-order rate constants for the transformation process were evaluated from the absorbance-time data and found to vary in the order of DCM > CHCl3. The values of the formation constant, Kf, for each complex are evaluated from Benesi-Hilebrand equation. Stability of the resulting complex in two solvents was also found to vary in the order of DCM > CHC13.

  13. Supercritical solvent coal extraction

    Science.gov (United States)

    Compton, L. E. (Inventor)

    1984-01-01

    Yields of soluble organic extract are increased up to about 50% by the supercritical extraction of particulate coal at a temperature below the polymerization temperature for coal extract fragments (450 C.) and a pressure from 500 psig to 5,000 psig by the conjoint use of a solvent mixture containing a low volatility, high critical temperature coal dissolution catalyst such as phenanthrene and a high volatility, low critical temperature solvent such as toluene.

  14. Cleaning without chlorinated solvents

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, L.M.; Simandl, R.F.

    1994-12-31

    Because of health and environmental concerns, many regulations have been passed in recent years regarding the use of chlorinated solvents. The Oak Ridge Y-12 Plant has had an active program to find alternatives for these solvents used in cleaning applications for the past 7 years. During this time frame, the quantity of solvents purchased has been reduced by 92%. The program has been a twofold effort. Vapor degreasers used in batch cleaning-operations have been replaced by ultrasonic cleaning with aqueous detergent, and other organic solvents have been identified for use in hand-wiping or specialty operations. In order to qualify these alternatives for use, experimentation was conducted on cleaning ability as well as effects on subsequent operations such as welding, painting and bonding. Cleaning ability was determined using techniques such as X-ray photoelectron spectroscopy (XPS) and Fourier Transform Infrared Spectroscopy (FTIR) which are capable of examining monolayer levels of contamination on a surface. Solvents have been identified for removal of rust preventative oils, lapping oils, machining coolants, lubricants, greases, and mold releases. Solvents have also been evaluated for cleaning urethane foam spray guns, swelling of urethanes and swelling of epoxies.

  15. Oxygenated Derivatives of Hydrocarbons

    Science.gov (United States)

    For the book entitled “Insect Hydrocarbons: Biology, Biochemistry and Chemical Ecology”, this chapter presents a comprehensive review of the occurrence, structure and function of oxygenated derivatives of hydrocarbons. The book chapter focuses on the occurrence, structural identification and functi...

  16. Hydrocarbon Spectral Database

    Science.gov (United States)

    SRD 115 Hydrocarbon Spectral Database (Web, free access)   All of the rotational spectral lines observed and reported in the open literature for 91 hydrocarbon molecules have been tabulated. The isotopic molecular species, assigned quantum numbers, observed frequency, estimated measurement uncertainty and reference are given for each transition reported.

  17. Solvent selection methodology for pharmaceutical processes: Solvent swap

    DEFF Research Database (Denmark)

    Papadakis, Emmanouil; Kumar Tula, Anjan; Gani, Rafiqul

    2016-01-01

    A method for the selection of appropriate solvents for the solvent swap task in pharmaceutical processes has been developed. This solvent swap method is based on the solvent selection method of Gani et al. (2006) and considers additional selection criteria such as boiling point difference, volati...

  18. Plasma devices for hydrocarbon reformation

    KAUST Repository

    Cha, Min Suk

    2017-02-16

    Plasma devices for hydrocarbon reformation are provided. Methods of using the devices for hydrocarbon reformation are also provided. The devices can include a liquid container to receive a hydrocarbon source, and a plasma torch configured to be submerged in the liquid. The plasma plume from the plasma torch can cause reformation of the hydrocarbon. The device can use a variety of plasma torches that can be arranged in a variety of positions in the liquid container. The devices can be used for the reformation of gaseous hydrocarbons and/or liquid hydrocarbons. The reformation can produce methane, lower hydrocarbons, higher hydrocarbons, hydrogen gas, water, carbon dioxide, carbon monoxide, or a combination thereof.

  19. Plant hydrocarbon recovery process

    Energy Technology Data Exchange (ETDEWEB)

    Dzadzic, P.M.; Price, M.C.; Shih, C.J.; Weil, T.A.

    1982-01-26

    A process for production and recovery of hydrocarbons from hydrocarbon-containing whole plants in a form suitable for use as chemical feedstocks or as hydrocarbon energy sources which process comprises: (A) pulverizing by grinding or chopping hydrocarbon-containing whole plants selected from the group consisting of euphorbiaceae, apocynaceae, asclepiadaceae, compositae, cactaceae and pinaceae families to a suitable particle size, (B) drying and preheating said particles in a reducing atmosphere under positive pressure (C) passing said particles through a thermal conversion zone containing a reducing atmosphere and with a residence time of 1 second to about 30 minutes at a temperature within the range of from about 200* C. To about 1000* C., (D) separately recovering the condensable vapors as liquids and the noncondensable gases in a condition suitable for use as chemical feedstocks or as hydrocarbon fuels.

  20. Anaerobic Microbial Transformation of Aromatic Hydrocarbons and Mixtures of Aromatic Hydrocarbons and Halogenated Solvents.

    Science.gov (United States)

    1992-08-25

    0.005 Pantothenic acid 0.005 p-Aminobenzoic ac id 0.005 (PABA) Cyanocobalamin (B1 2 ) 0.005 Thioctic (lipoic) acid 0.005 Coenzyme M (Mercapto...vitamin B12 ( cyanocobalamin ), and others -- had been reported to reductively dechlorinate CT in the presence of reducing 42 agents (Castro and Cray

  1. Purex process solvent: literature review

    Energy Technology Data Exchange (ETDEWEB)

    Geier, R.G.

    1979-10-01

    This document summarizes the data on Purex process solvent presently published in a variety of sources. Extracts from these various sources are presented herein and contain the work done, the salient results obtained, and the original, unaltered conclusions of the author of each paper. Three major areas are addressed: solvent stability, solvent quality testing, and solvent treatment processes. 34 references, 44 tables.

  2. Thixotropic Low-Solvent, Non-Hap Wheel Well Cleaner

    Science.gov (United States)

    1999-09-28

    mixture of linear alcohol ethoxylates having a HLB in the range of 2 to 15 as a stabilizer, and the balance water. The cleaning composition may also...as an isoparrafinic hydrocarbon solvent, from about 10% to about 50% of a mixture of linear alcohol ethoxylates having a HLB in the range of 2 to 15...the alkylphenol ethoxylate or an ethoxylated higher aliphatic flash point of said cleaning composition above 140° F., such alcohol, and (2) a fatty

  3. Fatal fulminant hepatic failure in a 'solvent abuser'.

    OpenAIRE

    McIntyre, A S; Long, R G

    1992-01-01

    The case of a 17 year old abuser of butane aerosols who developed fulminant hepatic failure after taking a proprietary engine or carburetor cleaner is described. Fatalities as a result of liver failure due to volatile hydrocarbons or solvents have not previously been reported. The likely toxins included isopropyl alcohol, methyl amyl alcohol, butylated hydroxytoluene as well as petroleum products, and evidence for their toxicity is reviewed. The possibility of increased susceptibility to hepa...

  4. Halogenated solvent remediation

    Science.gov (United States)

    Sorenson, Kent S.

    2004-08-31

    Methods for enhancing bioremediation of ground water contaminated with nonaqueous halogenated solvents are disclosed. A preferred method includes adding a composition to the ground water wherein the composition is an electron donor for microbe-mediated reductive dehalogenation of the halogenated solvents and enhances mass transfer of the halogenated solvents from residual source areas into the aqueous phase of the ground water. Illustrative compositions effective in these methods include surfactants such as C.sub.2 -C.sub.4 carboxylic acids and hydroxy acids, salts thereof, esters of C.sub.2 -C.sub.4 carboxylic acids and hydroxy acids, and mixtures thereof. Especially preferred compositions for use in these methods include lactic acid, salts of lactic acid, such as sodium lactate, lactate esters, and mixtures thereof. The microbes are either indigenous to the ground water, or such microbes can be added to the ground water in addition to the composition.

  5. Safe battery solvents

    Science.gov (United States)

    Harrup, Mason K.; Delmastro, Joseph R.; Stewart, Frederick F.; Luther, Thomas A.

    2007-10-23

    An ion transporting solvent maintains very low vapor pressure, contains flame retarding elements, and is nontoxic. The solvent in combination with common battery electrolyte salts can be used to replace the current carbonate electrolyte solution, creating a safer battery. It can also be used in combination with polymer gels or solid polymer electrolytes to produce polymer batteries with enhanced conductivity characteristics. The solvents may comprise a class of cyclic and acyclic low molecular weight phosphazenes compounds, comprising repeating phosphorus and nitrogen units forming a core backbone and ion-carrying pendent groups bound to the phosphorus. In preferred embodiments, the cyclic phosphazene comprises at least 3 phosphorus and nitrogen units, and the pendent groups are polyethers, polythioethers, polyether/polythioethers or any combination thereof, and/or other groups preferably comprising other atoms from Group 6B of the periodic table of elements.

  6. Analysis of hydrocarbons generated in coalbeds

    Science.gov (United States)

    Butala, Steven John M.

    This dissertation describes kinetic calculations using literature data to predict formation rates and product yields of oil and gas at typical low-temperature conditions in coalbeds. These data indicate that gas formation rates from hydrocarbon thermolysis are too low to have generated commercial quantities of natural gas, assuming bulk first-order kinetics. Acid-mineral-catalyzed cracking, transition-metal-catalyzed hydrogenolysis of liquid hydrocarbons, and catalyzed CO2 hydrogenation form gas at high rates. The gaseous product compositions for these reactions are nearly the same as those for typical natural coalbed gases, while those from thermal and catalytic cracking are more representative of atypical coalbed gases. Three Argonne Premium Coals (Upper-Freeport, Pittsburgh #8 and Lewiston-Stockton) were extracted with benzene in both Soxhlet and elevated pressure extraction (EPE) systems. The extracts were compared on the basis of dry mass yield and hydrocarbon profiles obtained by gas chromatography/mass spectrometry. The dry mass yields for the Upper-Freeport coal gave consistent results by both methods, while the yields from the Pittsburgh #8 and Lewiston-Stockton coals were greater by the EPE method. EPE required ˜90 vol. % less solvent compared to Soxhlet extraction. Single-ion-chromatograms of the Soxhlet extracts all exhibited bimodal distributions, while those of the EPE extracts did not. Hydrocarbons analyzed from Greater Green River Basin samples indicate that the natural oils in the basin originated from the coal seams. Analysis of artificially produced oil indicates that hydrous pyrolysis mimics generation of C15+ n-alkanes, but significant variations were found in the branched alkane, low-molecular-weight n-alkanes, and high-molecular-weight aromatic hydrocarbon distributions.

  7. Method for determining processability of a hydrocarbon containing feedstock

    Science.gov (United States)

    Schabron, John F.; Rovani, Jr., Joseph F.

    2013-09-10

    Disclosed herein is a method involving the steps of (a) precipitating an amount of asphaltenes from a liquid sample of a first hydrocarbon-containing feedstock having solvated asphaltenes therein with one or more first solvents in a column; (b) determining one or more solubility characteristics of the precipitated asphaltenes; (c) analyzing the one or more solubility characteristics of the precipitated asphaltenes; and (d) correlating a measurement of feedstock reactivity for the first hydrocarbon-containing feedstock sample with a mathematical parameter derived from the results of analyzing the one or more solubility characteristics of the precipitated asphaltenes.

  8. Cleaning up our act: Alternatives for hazardous solvents used in cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Shoemaker, J.D.; Meltzer, M.; Miscovich, D.; Montoya, D.; Goodrich, P.; Blycker, G.

    1994-01-01

    Lawrence Livermore National Laboratory (LLNL) has studied more than 70 alternative cleaners as potential replacements for chlorofluorocarbons (CFCs), halogenated hydrocarbons (e.g., trichloroethylene and trichloroethane), hydrocarbons (e.g., toluene and Stoddard Solvent), and volatile organic compounds (e.g., acetone, alcohols). This report summarizes LLNL`s findings after testing more than 45 proprietary formulations on bench-scale testing equipment and in more than 60 actual shops and laboratories. Cleaning applications included electronics fabrication, machine shops, optical lenses and hardware, and general cleaning. Most of the alternative cleaners are safer than the solvents previously used and many are nonhazardous, according to regulatory criteria.

  9. Species-Specific Cuticular Hydrocarbon Stability within European Myrmica Ants.

    Science.gov (United States)

    Guillem, Rhian M; Drijfhout, Falko P; Martin, Stephen J

    2016-10-01

    Recognition is a fundamental process on which all subsequent behaviors are based at every organizational level, from the gene up to the super-organism. At the whole organism level, visual recognition is the best understood. However, chemical communication is far more widespread than visual communication, but despite its importance is much less understood. Ants provide an excellent model system for chemical ecology studies as it is well established that compounds known as cuticular hydrocarbons (CHCs) are used as recognition cues in ants. Therefore, stable species-specific odors should exist, irrespective of geographic locality. We tested this hypothesis by comparing the CHC profiles of workers of twelve species of Myrmica ants from four countries across Europe, from Iberia to the Balkans and from the Mediterranean to Fennoscandia. CHCs remained qualitatively stable within each species, right down to the isomer level. Despite the morphological similarity that occurs within the genus Myrmica, their CHCs were highly diverse but remarkably species-specific and stable across wide geographical areas. This indicates a genetic mechanism under strong selection that produces these species-specific chemical profiles, despite each species encountering different environmental conditions across its range.

  10. A comparative study on the recovery of polycyclic aromatic hydrocarbons from fly ash and lignite coal.

    Science.gov (United States)

    Arditsoglou, Anastasia; Terzi, Eleni; Kalaitzoglou, Maria; Samara, Constantini

    2003-01-01

    The recovery of polycyclic aromatic hydrocarbons (PAHs) from lignite coal burnt in Greek power stations and the fly ash produced is examined comparatively using Soxhlet, ultrasonic and accelerated solvent extraction procedures with various organic solvents. Soxhlet using toluene/methanol mixture and accelerated solvent extraction/toluene were found to be the most efficient methods for fly ash PAHs, yielding average recoveries of about 80%. The accelerated solvent extraction/toluene procedure was superior for lignite PAHs, yielding 96% average recovery, whereas ultrasonic and Soxhlet extraction yielded relatively lower recoveries (75% and 67%, respectively).

  11. Does the ion-molecule reaction between HC tbnd CH rad + and HCN lead to CH 2dbnd CH-C tbnd N rad + ? A computational and experimental study of the reverse process

    Science.gov (United States)

    Jobst, Karl J.; Hasan, Syed A.; Terlouw, Johan K.

    2008-01-01

    The title ion-molecule reaction has been proposed to play an important role in interstellar chemistry if it yields acrylonitrile ions CH 2dbnd CH-C tbnd N rad + . This question was probed by examining the formation of HC tbnd CH rad + and HCN from low-energy ions CH 2dbnd CH-C tbnd N rad + and related isomers, using tandem mass spectrometry based experiments (D and 13C labelling) in conjunction with model chemistry calculations (CBS-QB3/APNO). We conclude that the title reaction is a barrierless multistep rearrangement that may not effectively compete with the straightforward formation of stable distonic ions HC dbnd CH-N dbnd CH rad + from HC tbnd CH rad + (ion)-HCN(dipole) encounter complexes.

  12. Thraustochytrid protists degrade hydrocarbons

    Digital Repository Service at National Institute of Oceanography (India)

    Raikar, M.T.; Raghukumar, S.; Vani, V.; David, J.J.; Chandramohan, D.

    Although thraustochytrid protists are known to be of widespread occurrence in the sea, their hydrocarbon-degrading abilities have never been investigated. We isolated thraustochytrids from coastal waters and sediments of Goa coast by enriching MPN...

  13. Synthesis and Characterization of Diorganotin Compounds {[R2Sn(ON=CHC6H5)]2O}2 and Crystal Structure of {[(C6H5CH2)2Sn(ON = CHC6H5)]2O}2

    Institute of Scientific and Technical Information of China (English)

    YIN,Han-Dong(尹汉东); XUE,Sheng-Cai(薛绳才); WANG,Qi-Bao(王其宝)

    2004-01-01

    Diorganotin compounds {[R2Sn(ON=CHC6H5)]2O}2 [R=C6H5CH2 (1), 2-FC6H4CH2 (2), 4-FC6H4CH2 (3),2-C1C6H4CH2 (4), 4-C1C6H4CH2 (5)] were synthesized by the reaction of R2SnO with HON=CHC6H5 in 1: 1 molar ratio in refluxing anhydrous benzene or toluene. They were characterized by elemental analysis, IR, 1H NMR and 119sn NMR spectroscopy. And two sets of 119sn chemical shifts were observed in the 119Sn NMR spectra of these compounds, indicating the presence of two types of environment around the tin atoms. The crystal structure of compound 1 was determined by X-ray single crystal diffraction analysis. The results showed that the crystal of compound 1 belongs to a monoclinic system with space group P21/c and unit cell dimensions: a= 1.0718(9) nm, b=1.9666(17) nm, c=2.0480(17) nm, β=96.4371(14)°, Dc= 1.450 g/cm3, Z=2, F(000)= 1888, V=4.290(6) nm3, μ= 1.206 mm -1, R1 =0.0405, wR2= 0.0786. The compound 1 belongs to centrosymmetric dimer structure mode with a four-membered central endo-cyclic Sn2O2 unit in which the bridging oxygen atoms are tri-coordinated. Each bridging oxygen atom also connects with an exo-cyclic tin atom. The endo- and exo-cyclic tin atoms are both five-coordinated, and have coordination geometry of distorted trigonal bipyramid.

  14. Enhanced Attenuation of Unsaturated Chlorinated Solvent Source Zones using Direct Hydrogen Delivery

    Science.gov (United States)

    2013-01-01

    solvents. This approach for bioremediation of unsaturated soils containing chlorinated solvents was originally proposed in a patent by Hughes et al...have been conducted on the use of hydrogen as an electron donor for the anaerobic bioremediation of saturated and unsaturated porous media (Evans and...aerobic environments. Figure 1. Comparison of H2T and bioventing. Air Injection ROI Hydrocarbons (Electron O2 (Electron acceptor) Vadose

  15. Studies of the effect of selected nondonor solvents on coal liquefaction yields

    Energy Technology Data Exchange (ETDEWEB)

    Jolley, R. L.; Rodgers, B. R.; Benjamin, B. M.; Poutsma, M. L.; Douglas, E. C.; McWhirter, D. A.

    1983-09-01

    The objective of this research program was to evaluate the effectiveness of selected nondonor solvents (i.e., solvents that are not generally considered to have hydrogen available for hydrogenolysis reactions) for the solubilization of coals. Principal criteria for selection of candidate solvents were that the compound should be representative of a major chemical class, should be present in reasonable concentration in coal liquid products, and should have the potential to participate in hydrogen redistribution reactions. Naphthalene, phenanthrene, pyrene, carbazole, phenanthridine, quinoline, 1-naphthol, and diphenyl ether were evaluated to determine their effect on coal liquefaction yields and were compared with phenol and two high-quality process solvents, Wilsonville SRC-I recycle solvent and Lummus ITSL heavy oil solvent. The high conversion efficacy of 1-naphthol may be attributed to its condensation to binaphthol and the consequent availability of hydrogen. The effectiveness of both the nitrogen heterocycles and the polycyclic aromatic hydrocarbon (PAH) compounds may be due to their polycyclic aromatic nature (i.e., possible hydrogen shuttling or transfer agents) and their physical solvent properties. The relative effectiveness for coal conversion of the Lummus ITSL heavy oil solvent as compared with the Wilsonville SRC-I process solvent may be attributed to the much higher concentration of 3-, 4-, and 5-ring PAH and hydroaromatic constituents in Lummus solvent. The chemistry of coal liquefaction and the development of recycle, hydrogen donor, and nondonor solvents are reviewed. The experimental methodology for tubing-bomb tests is outlined, and experimental problem areas are discussed.

  16. Organic solvent topical report

    Energy Technology Data Exchange (ETDEWEB)

    COWLEY, W.L.

    1999-05-13

    This report provides the basis for closing the organic solvent safety issue. Sufficient information is presented to conclude that risk posed by an organic solvent fire is within risk evaluation guidelines. This report updates information contained in Analysis of Consequences of Postulated Solvent Fires in Hanford Site Waste Tanks. WHC-SD-WM-CN-032. Rev. 0A (Cowley et al. 1996). However, this document will not replace Cowley et al (1996) as the primary reference for the Basis for Interim Operation (BIO) until the recently submitted BIO amendment (Hanson 1999) is approved by the US Department of Energy. This conclusion depends on the use of controls for preventing vehicle fuel fires and for limiting the use of flame cutting in areas where hot metal can fall on the waste surface.The required controls are given in the Tank Waste Remediation System Technical Safety Requirements (Noorani 1997b). This is a significant change from the conclusions presented in Revision 0 of this report. Revision 0 of this calcnote concluded that some organic solvent fire scenarios exceeded risk evaluation guidelines, even with controls imposed.

  17. Organic solvent topical report

    Energy Technology Data Exchange (ETDEWEB)

    Cowley, W.L.

    1998-04-30

    This report is the technical basis for the accident and consequence analyses used in the Hanford Tank Farms Basis for Interim Operation. The report also contains the scientific and engineering information and reference material needed to understand the organic solvent safety issue. This report includes comments received from the Chemical Reactions Subcommittee of the Tank Advisory Panel.

  18. STUDY OF SOLVENT AND CATALYST INTERACTIONS IN DIRECT COAL LIQUEFACTION

    Energy Technology Data Exchange (ETDEWEB)

    Michael T. Klein

    2000-01-01

    Using a reactor in which the coal is physically separated from the solid catalyst by a porous wall permeable to the hydrogen donor solvent, it was shown that direct contact between the catalyst and the coal is not required for catalyzed coal liquefaction. This occurs however only when there is a hydrogen atmosphere, as liquefaction with catalyst participation does not occur in a nitrogen atmosphere. Liquefaction by hydrogen transfer from the donor solvent itself does occur. This suggests that there is transfer of hydrogen from the catalyst to the coal via the solvent. The character of the solvent makes a significant difference, the better solvents being good hydrogen donors. These results indicate that the role of the catalyst may be to regenerate the spent hydrogen donor solvent during the liquefaction process. The peak temperature for volatiles evolution has been shown to be a reproducible measure of the coal rank. This was shown by an excellent correlation (R2 = 0.998) between peak volatiles temperatures (by TGA) and vitrinite reflectance. Using TG/MS, the volatiles contents of coals of a wide range of ranks was determined. The low rank coals emit largely phenols and some other oxygen compounds and olefins. The higher rank coals emit largely aromatic hydrocarbons and some olefins.

  19. Impact of Solvents Treatment on the Wettability of Froth Solids

    Science.gov (United States)

    Yang, Fan

    The purpose of this study is to investigate the impact of solvent addition to bitumen froth on the wettability of froth solids. The wettability of solids determines the transportation/partitioning of the solids between phases, which in turn affects the solids and water rejection in a Clark hot water extraction process (CHWE). The impact of solvents treatment on the wettability of froth solids was studied using both a model system and a real bitumen froth system. The vulnerabilities of four kinds of model minerals to hydrocarbon contamination/wettability alteration in different solvents were compared and discussed by considering solvent composition and mineral types. The wettability of solids extracted from the industrial froth using different solvents was also compared. The XRD analysis on these solids confirmed the partitioning behavior of solids observed in model solids system. The results from this study indicate that the composition of paraffinic/aromatic solvent in an industrial froth treatment process could be tailor-optimized to achieve a better solids/water rejection.

  20. Measurement and control of water content of organic solvents

    Energy Technology Data Exchange (ETDEWEB)

    Goderis, H.L.; Fouwe, B.L.; Van Cauwenbergh, S.M.; Tobback, P.P.

    1986-06-01

    An isotopic dilution procedure is described for the quantitative determination of the solubility of water in organic solvents as a function of the relative humidity at which the sample is equilibrated. /sup 3/H/sub 2/O is used as a tracer, and the relative humidity conditions are realized by incubation of the organic solvent above a saturated salt solution having a known water activity. The technique is applicable independent of the concentration range of water present, the minimum amount of moisture being only limited by the concentration of the tritium label used. Solubility isotherms of water in hydrocarbon solvents such as n-hexane are sigmoidal in shape, reflecting cooperative effects in the solubilization of water molecules at the higher relative humidity portion of the curve. Solubility increases with increasing temperature.

  1. Solvent-mediated pathways to gelation and phase separation in suspensions of grafted nanoparticles

    KAUST Repository

    Anyfantakis, Manos

    2009-01-01

    We explore the role of the solvent medium on the interplay between gelation and phase separation in suspensions of organosilicate planar hybrids grafted with hydrocarbon chains. We establish their phase diagram by means of dynamic light scattering, rheology and visual observations, and different routes to gelation, depending on the solvent used. In agreement with earlier works, the solvent quality for the grafted chains at a given temperature controls the balance between attractions and repulsions, and hence the phase diagram of the nanoparticles and their tendency to gel. Here we show how to tune the suspension state and hence its rheology. For decane, a good solvent for the hydrocarbon chains, gelation occurs at rather low volume fractions in the presence of phase separation. This is due to the interdigitation of solvent molecules with the grafted chains, resulting in their crystalline packing that promotes the attraction between particles. For toluene, a solvent of reduced quality for the hydrocarbon chains, no interdigitation takes place, and hence gelation is triggered by clustering at higher volume fractions before phase separation. Our results support the generic picture of complex kinetic arrest/phase separation interplay in soft matter, where phase separation can proceed, be interrupted or be completely inhibited. A number of interesting possibilities for tailoring the rheology of grafted colloidal systems emerge. © 2009 The Royal Society of Chemistry.

  2. Seawater-cultured Botryococcus braunii for efficient hydrocarbon extraction.

    Directory of Open Access Journals (Sweden)

    Kenichi Furuhashi

    Full Text Available As a potential source of biofuel, the green colonial microalga Botryococcus braunii produces large amounts of hydrocarbons that are accumulated in the extracellular matrix. Generally, pretreatment such as drying or heating of wet algae is needed for sufficient recoveries of hydrocarbons from B. braunii using organic solvents. In this study, the Showa strain of B. braunii was cultured in media derived from the modified Chu13 medium by supplying artificial seawater, natural seawater, or NaCl. After a certain period of culture in the media with an osmotic pressure corresponding to 1/4-seawater, hydrocarbon recovery rates exceeding 90% were obtained by simply mixing intact wet algae with n-hexane without any pretreatments and the results using the present culture conditions indicate the potential for hydrocarbon milking.Seawater was used for efficient hydrocarbon extraction from Botryococcus braunii. The alga was cultured in media prepared with seawater or NaCl. Hydrocarbon recovery rate exceeding 90% was obtained without any pretreatment.

  3. Metabolism of Benzene, Toluene, and Xylene Hydrocarbons in Soil†

    OpenAIRE

    Tsao, C.-W.; Song, H. -G.; Bartha, R

    1998-01-01

    Enrichment cultures obtained from soil exposed to benzene, toluene, and xylene (BTX) mineralized benzene and toluene but cometabolized only xylene isomers, forming polymeric residues. This observation prompted us to investigate the metabolism of 14C-labeled BTX hydrocarbons in soil, either individually or as mixtures. BTX-supplemented soil was incubated aerobically for up to 4 weeks in a sealed system that automatically replenished any O2 consumed. The decrease in solvent vapors and the produ...

  4. Solvent Immersion Imprint Lithography

    Energy Technology Data Exchange (ETDEWEB)

    Vasdekis, Andreas E.; Wilkins, Michael J.; Grate, Jay W.; Kelly, Ryan T.; Konopka, Allan; Xantheas, Sotiris S.; Chang, M. T.

    2014-06-21

    The mechanism of polymer disolution was explored for polymer microsystem prototyping, including microfluidics and optofluidics. Polymer films are immersed in a solvent, imprinted and finally brought into contact with a non-modified surface to permanently bond. The underlying polymer-solvent interactions were experimentally and theoretically investigated, and enabled rapid polymer microsystem prototyping. During imprinting, small molecule integration in the molded surfaces was feasible, a principle applied to oxygen sensing. Polystyrene (PS) was employed for microbiological studies at extreme environmental conditions. The thermophile anaerobe Clostridium Thermocellum was grown in PS pore-scale micromodels, revealing a double mean generation lifetime than under ideal culture conditions. Microsystem prototyping through directed polymer dissolution is simple and accessible, while simultaneous patterning, bonding, and surface/volume functionalization are possible in less than one minute.

  5. Role of solvent/non-solvent ratio on microsphere formation using the solvent removal method.

    Science.gov (United States)

    Godbee, J; Scott, E; Pattamunuch, P; Chen, S; Mathiowitz, E

    2004-03-01

    The importance of good solvent concentration in the non-solvent mixture and the non-solvent viscosity on the ability to form microspheres using solvent removal process was investigated. The higher the viscosity of the polymer solutions, the higher the concentration of good solvent needed in the nonsolvent mixture to produce microspheres. This finding was due to faster precipitation of the polymer phase. Also, the addition of a model drug, fluorescein isothiocyanate conjugated-labelled bovine serum albumin, to the polymer solution (10% poly-L-lactic acid:poly(fumaric-co-sebacic) anhydride in methylene chloride) resulted in an overall lower polymer solution viscosity (15.5 cP with fluorescein isothiocyanate conjugated-labelled bovine serum albumin as compared with 18.25 cP for blank polymer at 25 degrees C). Additionally, the effect of good solvent concentration on non-solvent viscosity was evaluated, and the viscosity decreased as the concentration of good solvent increased. The effect of good solvent concentration on the non-solvent mixture on sphere formation was of great importance. Microspheres would not form when the good polymer solvent (methylene chloride) in the non-solvent phase was too low (below 175 ml for poly-L-lactic acid or 150 ml for poly(D,L-lactidco-glycolid)) or was replaced by another good solvent such as ethyl acetate, even though the same viscosity was achieved. It was shown that the concentration of the good solvent in the non-solvent mixture was more of a controlling factor than the viscosity of the non-solvent mixture in microsphere formation and the findings support the conclusion that diffusion is the main controlling parameter in solvent removal.

  6. ANALYSIS OF THE KINETICS OF SOLVOLYSIS OF P-NITROPHENYLSULFONYLMETHYL PERCHLORATE IN BINARY ALCOHOLIC MIXTURES IN TERMS OF THE THERMODYNAMIC PROPERTIES OF THE SOLVENT MIXTURES

    NARCIS (Netherlands)

    WIJNEN, JW; ENGBERTS, JBFN; BLANDAMER, MJ

    1993-01-01

    Rate constants are reported for the solvolysis of p-nitrophenylsulfonylmethyl perchlorate in binary ethanolic and methanolic mixtures at 298.2 K. Co-solvents include hydrocarbons, chlorinated hydrocarbons and 1,4-dioxane. The kinetic data are examined in terms of the effect of decreasing mole fracti

  7. Selectivity of oxazolidine derivatives in the separation of C/sub 5/ hydrocarbons with different degrees of saturation

    Energy Technology Data Exchange (ETDEWEB)

    Apter, Yu.M.; Gaile, A.A.; Proskuryakov, V.A.; Semenov, L.V.

    1980-01-01

    An increase in the selectivity of cyclic compound solvents in the separation of hydrocarbons of different degrees of saturation can be attained by reducing the size of the ring and introducing an additional heteroatom into the ring. In connection with this, the selectivity of oxazolidine derivatives, differing in respect to their structure from known extractants -- pyrrolidine derivatives -- by the presence of a second heteroatom in the ring and from morpholine derivatives by the smaller ring size was studied. It was found that oxazolidine derivatives show higher selectivity in respect to hydrocarbon systems than the corresponding pyrrolidine and morpholine derivatives. The dissolving capacity of oxazolidine derivatives in respect to unsaturated hydrocarbons is higher than that of isomeric compounds of the morpholine series. The values of the activity coefficients of the C/sub 5/ hydrocarbons at infinite dilution in polar solvents correlate satisfactorily with the ionization potentials of the hydrocarbons.

  8. Diamex solvent regeneration studies

    Energy Technology Data Exchange (ETDEWEB)

    Nicol, C.; Cames, B.; Margot, L.; Ramain, L. [CEA/VALRHO - site de Marcoule, Dept. de Recherche en Retraitement et en Vitrification, DRRV, 30 - Marcoule (France)

    2000-07-01

    The CEA has undertaken the development of the DIAMEX process as the first step in the strategy aiming at recovering minor actinides which could then be transmuted or separately conditioned. The scientific feasibility of this process was demonstrated during counter current hot tests operated in 1993. Then experimental works were conducted, on one hand to optimise the extractant formula, on the other hand to improve the flowsheet. Reference extractant and flowsheet were then chosen, respectively in 1995 and 1996. The next step, still in progress, is the demonstration of the DIAMEX technical feasibility (in 2002); this means that the flowsheet should include solvent regeneration treatments. In this aim, degradation studies were performed to quantify main degradation products, and identify those which could be disturbing in the process. This paper deals with experimental studies performed with intend to propose a regeneration treatment, included in the flowsheet, so that the solvent could be recycled. It comprises: - Quantification of the main degradation products issued from radiolysis or hydrolysis, which are methyl octyl amine (MOA) and carboxylic acids; - Effects of these products on extracting and hydrodynamics performances of the process; - Study of methods able to remove mainly disturbing degradation products. Acidic scrubbing, which are performed in the scrubbing and stripping sections of the DIAMEX process, should allow the quantitative removal of methyl octyl amine. Then basic scrubbings, which were more especially studied, should eliminate at least 80% of carboxylic acids, and part of the cations remaining in the solvent. (authors)

  9. Hydrogenation of unsaturated hydrocarbons in the presence of palladium complexes fixed on a polymeric support

    Energy Technology Data Exchange (ETDEWEB)

    Gvinter, L.I.; Ignatov, V.M.; Suvorova, L.N.; Sharf, V.Z.

    1987-01-01

    A new metal-complex Pd catalyst fixed on a polymer matrix has been synthesized. It exhibits high activity and stability in the hydrogenation of unsaturated hydrocarbons and does not require additional activation by NaBH/sub 4/. The activity of the catalyst depends on the nature and composition of the solvent. In a mixed benzene-methanol solvent, the rate of the reaction is higher than in pure benzene. 4 references, 3 tables.

  10. Impurity Distribution Behavior in Caprolactam Extraction with Environmentally Benign Mixed Solvents

    NARCIS (Netherlands)

    Delden, van M.L.; Drumm, C.; Kuipers, N.J.M.; Haan, de A.B.

    2006-01-01

    In a previous study a solvent mixture of heptane containing 40 mass % heptanol was selected as an alternative in the industrial extraction of caprolactam to replace benzene, toluene, or chlorinated hydrocarbons. This work reports the equilibrium distribution ratio of caprolactam and four model impur

  11. Combining Solvent Extraction and Bioremediation for Removing Weathered Petroleum from Contaminated Soil

    Institute of Scientific and Technical Information of China (English)

    WU Guo-Zhong; F.COULON; YANG Yue-Wei; LI Hong; SUI Hong

    2013-01-01

    This study aimed to evaluate the efficacy,practicality and sustainability of a combined approach based on solvent extraction and biodegradation to remediate the soils contaminated with high levels of weathered petroleum hydrocarbons.The soils used in this study were obtained from the Shengli Oilfield in China,which had a long history of contamination with high concentrations of petroleum hydrocarbons.The contaminated soils were washed using a composite organic solvent consisting of hexane and pentane (4:1,v/v) and then bioremediated in microcosms which were bioaugmentated with Bacillus subtilis FQ06 strains and/or rhamnolipid.The optimal solvent extraction conditions were determined as extraction for 20 min at 25 ℃ with solvent-soil ratio of 6:1 (v/w).On this basis,total petroleum hydrocarbon was decreased from 140000 to 14000 mg kg-1,which was further reduced to < 4000 mg kg-1 by subsequent bioremediation for 132 d.Sustainability assessment of this integrated technology showed its good performance for both short-and long-term effectiveness.Overall the results encouraged its application for remediating contaminated sites especially with high concentration weathered hydrocarbons.

  12. Screening method for solvent selection used in tar removal by the absorption process.

    Science.gov (United States)

    Masurel, Eve; Authier, Olivier; Castel, Christophe; Roizard, Christine

    2015-01-01

    The aim of this paper is the study of the treatment of flue gas issued from a process of biomass gasification in fluidized bed. The flue gas contains tar which should be selectively removed from the fuel components of interest (e.g. H2, CO and light hydrocarbons) to avoid condensation and deposits in internal combustion engine. The chosen flue gas treatment is the gas-liquid absorption using solvents, which present specific physicochemical properties (e.g. solubility, viscosity, volatility and chemical and thermal stability) in order to optimize the unit on energetic, technico-economic and environmental criteria. The rational choice of the proper solvent is essential for solving the tar issue. The preselection of the solvents is made using a Hansen parameter in order to evaluate the tar solubility and the saturation vapour pressure of the solvent is obtained using Antoine law. Among the nine families of screened solvents (alcohols, amines, ketones, halogenates, ethers, esters, hydrocarbons, sulphured and chlorinates), acids methyl esters arise as solvents of interest. Methyl oleate has then been selected and studied furthermore. Experimental liquid-vapour equilibrium data using bubbling point and absorption cell measurements and theoretical results obtained by the UNIFAC-Dortmund model confirm the high potential of this solvent and the good agreement between experimental and theoretical results.

  13. The Role of Saturated Hydrocarbon in Enrichment of Cu, Pb, Znin Kupferschiefer, Southwestern Poland

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In order to clarify the role of organic matter in the enrichment of base metal, 10 samples of the PermianKupferschiefer from southwestern Poland were analyzed by using microscopic and geochemical methods. The re-suts indicate that the solvent extracts have been depleted in the samples with high Cu, Pb, Zn contents. This de-pletion occurred preferably in saturated hydrocarbons. Saturated hydrocarbons served as hydrogen donor for ther-mochemical sulfate reduction (TSR). The GC traces of saturated hydrocarbon show that the depletion occurredmainly in long-chain n-alkanes.

  14. Thermal pre-treatment of wet microalgae harvest for efficient hydrocarbon recovery

    Energy Technology Data Exchange (ETDEWEB)

    Kita, K.; Okada, S.; Sekino, H.; Imou, K.; Yokoyama, S. [Laboratory of Biological and Mechanical Engineering, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657 (Japan); Amano, T. [Technology Research Institute, Tokyo Gas Co., Ltd., 1-7-7 Suehiro-cho, Tsurumi-ku Yokohama, Kanagawa 230-0045 (Japan)

    2010-07-15

    Botryococcus braunii, a green colonial microalga, is an unusually rich renewable source of hydrocarbons. In this study, wet microalgae harvest was thermally pretreated to enhance hydrocarbon recovery using a solvent extraction process. Samples containing a mixture of B. braunii and water were kept below 100 C for 10 min. The observed hydrocarbon recovery was 97.8% at 90 C. The extraction results suggest that the energy-intensive concentration and drying processes of the harvest could be eliminated. The proposed thermal pretreatment would revolutionize the conventional downstream processes. (author)

  15. Occupational solvent exposure and cognition

    Science.gov (United States)

    Sabbath, E.L.; Glymour, M.M.; Berr, C.; Singh-Manoux, A.; Zins, M.; Goldberg, M.

    2012-01-01

    Objective: Chronic occupational solvent exposure is associated with long-term cognitive deficits. Cognitive reserve may protect solvent-exposed workers from cognitive impairment. We tested whether the association between chronic solvent exposure and cognition varied by educational attainment, a proxy for cognitive reserve. Methods: Data were drawn from a prospective cohort of French national gas and electricity (GAZEL) employees (n = 4,134). Lifetime exposure to 4 solvent types (chlorinated solvents, petroleum solvents, benzene, and nonbenzene aromatic solvents) was assessed using a validated job-exposure matrix. Education was dichotomized at less than secondary school or below. Cognitive impairment was defined as scoring below the 25th percentile on the Digit Symbol Substitution Test at mean age 59 (SD 2.8; 88% of participants were retired at testing). Log-binomial regression was used to model risk ratios (RRs) for poor cognition as predicted by solvent exposure, stratified by education and adjusted for sociodemographic and behavioral factors. Results: Solvent exposure rates were higher among less-educated patients. Within this group, there was a dose-response relationship between lifetime exposure to each solvent type and RR for poor cognition (e.g., for high exposure to benzene, RR = 1.24, 95% confidence interval 1.09–1.41), with significant linear trends (p < 0.05) in 3 out of 4 solvent types. Recency of solvent exposure also predicted worse cognition among less-educated patients. Among those with secondary education or higher, there was no significant or near-significant relationship between any quantification of solvent exposure and cognition. Conclusions: Solvent exposure is associated with poor cognition only among less-educated individuals. Higher cognitive reserve in the more-educated group may explain this finding. PMID:22641403

  16. Thermodiffusion of polycyclic aromatic hydrocarbons in binary mixtures

    Science.gov (United States)

    Hashmi, Sara M.; Senthilnathan, Sid; Firoozabadi, Abbas

    2016-11-01

    Thermodiffusion in liquid mixtures may explain some counter-intuitive but naturally occurring phenomena such as hydrocarbon reservoirs with heavier component(s) stratified on top of lighter ones. However, beyond benchmark systems, systematic measurements of thermodiffusion in binary organic mixtures are lacking. We use an optical beam deflection apparatus to simultaneously probe Fickian and thermal diffusion in binary solution mixtures of polycyclic aromatic hydrocarbons dissolved in alkanes, and measure both Fickian diffusion D and the Soret coefficient ST, and then obtain the thermodiffusion coefficient DT. In a series of nine binary mixtures, we vary both the size of the aromatic compound from two to four rings, as well as the length of the alkane chain from 6 to 16 carbons. To probe the effect of increasing ring size, we include a 6-ringed aromatic compound, coronene, and toluene as a solvent, due to the insolubility of coronene in alkanes. Our results suggest that Fickian diffusion increases with the inverse of solvent viscosity and also with decreasing molecular weight of the solute. While both of these trends match our intuition, the behavior of ST and DT is more complicated. We find that ST and DT increase with the solute molecular weight when the solvent is held fixed and that the impact of solute ring size is higher in shorter chain alkane solvents.

  17. Effect of coal-derived-liquid solvent on the hydrogenation and restrictive diffusion of nickel porphyrins

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, C.H.; Massoth, F.E.; Lee, S.Y.; Seader, J.D. (University of Utah, Salt Lake City, UT (USA). Dept. of Fuels Engineering)

    1991-12-01

    Hydrogenation of nickel porphyrins was carried out at 335{degree}C and 50 atm hydrogen pressure with two Ni-Mo/alumina catalysts of different pore sizes. Solvents employed were a triple-hydrotreated coal-derived-liquid and four pure hydrocarbons (n-decane, decalin, tetralin, and mesitylene). Reaction rates in the hydrotreated coal-derived-liquid solvent were higher than those in pure solvents with higher hydrogen solubilities. The results were attributed to the greater hydrogen-donor ability of the hydrotreated coal-derived-liquid solvent. Reaction rates of different catalyst particle sizes were used to calculate effective diffusivities under processing conditions. Reactivity was significantly affected by catalyst deactivation via coke buildup at catalyst pore mouths. Accounting for this additional diffusional constraint, restrictive diffusion in the coal-liquid solvent under processing conditions was found to be in reasonable agreement with approximate hydrodynamic theory for non-reactive conditions. 33 refs., 6 figs., 4 tabs.

  18. Solvent effects in chemistry

    CERN Document Server

    Buncel, Erwin

    2015-01-01

    This book introduces the concepts, theory and experimental knowledge concerning solvent effects on the rate and equilibrium of chemical reactions of all kinds.  It begins with basic thermodynamics and kinetics, building on this foundation to demonstrate how a more detailed understanding of these effects may be used to aid in determination of reaction mechanisms, and to aid in planning syntheses. Consideration is given to theoretical calculations (quantum chemistry, molecular dynamics, etc.), to statistical methods (chemometrics), and to modern day concerns such as ""green"" chemistry, where ut

  19. Apparatus and methods for hydrocarbon extraction

    Science.gov (United States)

    Bohnert, George W.; Verhulst, Galen G.

    2016-04-26

    Systems and methods for hydrocarbon extraction from hydrocarbon-containing material. Such systems and methods relate to extracting hydrocarbon from hydrocarbon-containing material employing a non-aqueous extractant. Additionally, such systems and methods relate to recovering and reusing non-aqueous extractant employed for extracting hydrocarbon from hydrocarbon-containing material.

  20. Hydrocarbons preserved in a ~2.7 Ga outcrop sample from the Fortescue Group, Pilbara Craton, Western Australia.

    Science.gov (United States)

    Hoshino, Y; Flannery, D T; Walter, M R; George, S C

    2015-03-01

    The hydrocarbons preserved in an Archean rock were extracted, and their composition and distribution in consecutive slices from the outside to the inside of the rock were examined. The 2.7 Ga rock was collected from the Fortescue Group in the Pilbara region, Western Australia. The bitumen I (solvent-extracted rock) and bitumen II (solvent-extracted hydrochloric acid-treated rock) fractions have different hydrocarbon compositions. Bitumen I contains only trace amounts of aliphatic hydrocarbons and virtually no aromatic hydrocarbons. In contrast, bitumen II contains abundant aliphatic and aromatic hydrocarbons. The difference seems to reflect the weathering history and preservational environment of the investigated rock. Aliphatic hydrocarbons in bitumen I are considered to be mainly from later hydrocarbon inputs, after initial deposition and burial, and are therefore not indigenous. The lack of aromatic hydrocarbons in bitumen I suggests a severe weathering environment since uplift and exposure of the rock at the Earth's surface in the Cenozoic. On the other hand, the high abundance of aromatic hydrocarbons in bitumen II suggests that bitumen II hydrocarbons have been physically isolated from removal by their encapsulation within carbonate minerals. The richness of aromatic hydrocarbons and the relative scarcity of aliphatic hydrocarbons may reflect the original compositions of organic materials biosynthesised in ancient organisms in the Archean era, or the high thermal maturity of the rock. Cyanobacterial biomarkers were observed in the surficial slices of the rock, which may indicate that endolithic cyanobacteria inhabited the surface outcrop. The distribution of aliphatic and aromatic hydrocarbons implies a high thermal maturity, which is consistent with the lack of any specific biomarkers, such as hopanes and steranes, and the prehnite-pumpellyite facies metamorphic grade.

  1. Optrode for sensing hydrocarbons

    Science.gov (United States)

    Miller, Holly; Milanovich, Fred P.; Hirschfeld, Tomas B.; Miller, Fred S.

    1987-01-01

    A two-phase system employing the Fujiwara reaction is provided for the fluorometric detection of halogenated hydrocarbons. A fiber optic is utilized to illuminate a column of pyridine trapped in a capillary tube coaxially attached at one end to the illuminating end of the fiber optic. A strongly alkaline condition necessary for the reaction is maintained by providing a reservoir of alkali in contact with the column of pyridine, the surface of contact being adjacent to the illuminating end of the fiber optic. A semipermeable membrane caps the other end of the capillary tube, the membrane being preferentially permeable to the halogenated hydrocarbon and but preferentially impermeable to water and pyridine. As the halogenated hydrocarbon diffuses through the membrane and into the column of pyridine, fluorescent reaction products are formed. Light propagated by the fiber optic from a light source, excites the fluorescent products. Light from the fluorescence emission is also collected by the same fiber optic and transmitted to a detector. The intensity of the fluorescence gives a measure of the concentration of the halogenated hydrocarbons.

  2. Sex-specific genotype-by-environment interactions for cuticular hydrocarbon expression in decorated crickets, Gryllodes sigillatus: implications for the evolution of signal reliability.

    Science.gov (United States)

    Weddle, C B; Mitchell, C; Bay, S K; Sakaluk, S K; Hunt, J

    2012-10-01

    Phenotypic traits that convey information about individual identity or quality are important in animal social interactions, and the degree to which such traits are influenced by environmental variation can have profound effects on the reliability of these cues. Using inbred genetic lines of the decorated cricket, Gryllodes sigillatus, we manipulated diet quality to test how the cuticular hydrocarbon (CHC) profiles of males and females respond across two different nutritional rearing environments. There were significant differences between lines in the CHC profiles of females, but the effect of diet was not quite statistically significant. There was no significant genotype-by-environment interaction (GEI), suggesting that environmental effects on phenotypic variation in female CHCs are independent of genotype. There was, however, a significant effect of GEI for males, with changes in both signal quantity and content, suggesting that environmental effects on phenotypic expression of male CHCs are dependent on genotype. The differential response of male and female CHC expression to variation in the nutritional environment suggests that these chemical cues may be under sex-specific selection for signal reliability. Female CHCs show the characteristics of reliable cues of identity: high genetic variability, low condition dependence and a high degree of genetic determination. This supports earlier work showing that female CHCs are used in self-recognition to identify previous mates and facilitate polyandry. In contrast, male CHCs show the characteristics of reliable cues of quality: condition dependence and a relatively higher degree of environmental determination. This suggests that male CHCs are likely to function as cues of underlying quality during mate choice and/or male dominance interactions.

  3. Mantle hydrocarbons: abiotic or biotic?

    Science.gov (United States)

    Sugisaki, R; Mimura, K

    1994-06-01

    Analyses of 227 rocks from fifty localities throughout the world showed that mantle derived rocks such as tectonized peridotites in ophiolite sequences (tectonites) arid peridotite xenoliths in alkali basalts contain heavier hydrocarbons (n-alkanes), whereas igneous rocks produced by magmas such as gabbro arid granite lack them. The occurrence of hydrocarbons indicates that they were not derived either from laboratory contamination or from held contamination; these compounds found in the mantle-derived rocks are called here "mantle hydrocarbons." The existence of hydrocarbons correlates with petrogenesis. For example, peridotite cumulates produced by magmatic differentiation lack hydrocarbons whereas peridotite xenoliths derived from the mantle contain them. Gas chromatographic-mass spectrometric records of the mantle hydrocarbons resemble those of aliphatics in meteorites and in petroleum. Features of the hydrocarbons are that (a) the mantle hydrocarbons reside mainly along grain boundaries and in fluid inclusions of minerals; (b) heavier isoprenoids such as pristane and phytane are present; and (c) delta 13C of the mantle hydrocarbons is uniform (about -27%). Possible origins for the mantle hydrocarbons are as follows. (1) They were in organically synthesized by Fischer-Tropsch type reaction in the mantle. (2) They were delivered by meteorites and comets to the early Earth. (3) They were recycled by subduction. The mantle hydrocarbons in the cases of (1) and (2) are abiogenic and those in (3) are mainly biogenic. It appears that hydrocarbons may survive high pressures and temperatures in the mantle, but they are decomposed into lighter hydrocarbon gases such as CH4 at lower pressures when magmas intrude into the crust; consequently, peridotite cumulates do not contain heavier hydrocarbons but possess hydrocarbon gases up to C4H10.

  4. Bacterial sources for phenylalkane hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, L.; Winans, R.E. [Argonne National Lab., IL (United States); Langworthy, T. [Univ. of South Dakota, Vermillion, SD (United States)

    1996-10-01

    The presence of phenylalkane hydrocarbons in geochemical samples has been the source of much controversy. Although an anthropogenic input from detergent sources always appears likely, the distribution of phenylalkane hydrocarbons in some cases far exceeding that attributed to detergent input has led to a reappraisal of this view. Indeed, recent work involving analysis of the lipid hydrocarbon extracts from extant Thermoplasma bacteria has revealed the presence of phenylalkane hydrocarbons. The presence of phenylalkane hydrocarbons in sedimentary organic matter may therefore represent potential biological markers for thermophilic bacteria.

  5. Microbial degradation of petroleum hydrocarbons.

    Science.gov (United States)

    Varjani, Sunita J

    2017-01-01

    Petroleum hydrocarbon pollutants are recalcitrant compounds and are classified as priority pollutants. Cleaning up of these pollutants from environment is a real world problem. Bioremediation has become a major method employed in restoration of petroleum hydrocarbon polluted environments that makes use of natural microbial biodegradation activity. Petroleum hydrocarbons utilizing microorganisms are ubiquitously distributed in environment. They naturally biodegrade pollutants and thereby remove them from the environment. Removal of petroleum hydrocarbon pollutants from environment by applying oleophilic microorganisms (individual isolate/consortium of microorganisms) is ecofriendly and economic. Microbial biodegradation of petroleum hydrocarbon pollutants employs the enzyme catalytic activities of microorganisms to enhance the rate of pollutants degradation. This article provides an overview about bioremediation for petroleum hydrocarbon pollutants. It also includes explanation about hydrocarbon metabolism in microorganisms with a special focus on new insights obtained during past couple of years. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Superconductivity in aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Kubozono, Yoshihiro, E-mail: kubozono@cc.okayama-u.ac.jp [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Research Center of New Functional Materials for Energy Production, Storage and Transport, Okayama University, Okayama 700-8530 (Japan); Japan Science and Technology Agency, ACT-C, Kawaguchi 332-0012 (Japan); Goto, Hidenori; Jabuchi, Taihei [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Yokoya, Takayoshi [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Research Center of New Functional Materials for Energy Production, Storage and Transport, Okayama University, Okayama 700-8530 (Japan); Kambe, Takashi [Department of Physics, Okayama University, Okayama 700-8530 (Japan); Sakai, Yusuke; Izumi, Masanari; Zheng, Lu; Hamao, Shino; Nguyen, Huyen L.T. [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Sakata, Masafumi; Kagayama, Tomoko; Shimizu, Katsuya [Center of Science and Technology under Extreme Conditions, Osaka University, Osaka 560-8531 (Japan)

    2015-07-15

    Highlights: • Aromatic superconductor is one of core research subjects in superconductivity. Superconductivity is observed in certain metal-doped aromatic hydrocarbons. Some serious problems to be solved exist for future advancement of the research. This article shows the present status of aromatic superconductors. - Abstract: ‘Aromatic hydrocarbon’ implies an organic molecule that satisfies the (4n + 2) π-electron rule and consists of benzene rings. Doping solid aromatic hydrocarbons with metals provides the superconductivity. The first discovery of such superconductivity was made for K-doped picene (K{sub x}picene, five benzene rings). Its superconducting transition temperatures (T{sub c}’s) were 7 and 18 K. Recently, we found a new superconducting K{sub x}picene phase with a T{sub c} as high as 14 K, so we now know that K{sub x}picene possesses multiple superconducting phases. Besides K{sub x}picene, we discovered new superconductors such as Rb{sub x}picene and Ca{sub x}picene. A most serious problem is that the shielding fraction is ⩽15% for K{sub x}picene and Rb{sub x}picene, and it is often ∼1% for other superconductors. Such low shielding fractions have made it difficult to determine the crystal structures of superconducting phases. Nevertheless, many research groups have expended a great deal of effort to make high quality hydrocarbon superconductors in the five years since the discovery of hydrocarbon superconductivity. At the present stage, superconductivity is observed in certain metal-doped aromatic hydrocarbons (picene, phenanthrene and dibenzopentacene), but the shielding fraction remains stubbornly low. The highest priority research area is to prepare aromatic superconductors with a high superconducting volume-fraction. Despite these difficulties, aromatic superconductivity is still a core research target and presents interesting and potentially breakthrough challenges, such as the positive pressure dependence of T{sub c} that is clearly

  7. Liquid phase in situ hydrodeoxygenation of biomass-derived phenolic compounds to hydrocarbons over bifunctional catalysts

    Science.gov (United States)

    Junfeng Feng; Chung-yun Hse; Zhongzhi Yang; Kui Wang; Jianchun Jiang; Junming Xu

    2017-01-01

    The objective of this study was to find an effective method for converting renewable biomass-derived phenolic compounds into hydrocarbons bio-fuel via in situ catalytic hydrodeoxygenation. The in situ hydrodeoxygenation of biomass-derived phenolic compounds was carried out in methanol-water solvent over bifunctional catalysts of Raney Ni and HZSM-5 or H-Beta. In the in...

  8. Membrane separation of hydrocarbons

    Science.gov (United States)

    Chang, Y. Alice; Kulkarni, Sudhir S.; Funk, Edward W.

    1986-01-01

    Mixtures of heavy oils and light hydrocarbons may be separated by passing the mixture through a polymeric membrane. The membrane which is utilized to effect the separation comprises a polymer which is capable of maintaining its integrity in the presence of hydrocarbon compounds and which has been modified by being subjected to the action of a sulfonating agent. Sulfonating agents which may be employed will include fuming sulfuric acid, chlorosulfonic acid, sulfur trioxide, etc., the surface or bulk modified polymer will contain a degree of sulfonation ranging from about 15 to about 50%. The separation process is effected at temperatures ranging from about ambient to about 100.degree. C. and pressures ranging from about 50 to about 1000 psig.

  9. Evaluation of mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) in pure mineral hydrocarbon-based cosmetics and cosmetic raw materials using 1H NMR spectroscopy

    Science.gov (United States)

    Lachenmeier, Dirk W.; Mildau, Gerd; Rullmann, Anke; Marx, Gerhard; Walch, Stephan G.; Hartwig, Andrea; Kuballa, Thomas

    2017-01-01

    Mineral hydrocarbons consist of two fractions, mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH). MOAH is a potential public health hazard because it may include carcinogenic polycyclic compounds. In the present study, 400 MHz nuclear magnetic resonance (NMR) spectroscopy was introduced, in the context of official controls, to measure MOSH and MOAH in raw materials or pure mineral hydrocarbon final products (cosmetics and medicinal products). Quantitative determination (qNMR) has been established using the ERETIC methodology (electronic reference to access in vivo concentrations) based on the PULCON principle (pulse length based concentration determination). Various mineral hydrocarbons (e.g., white oils, paraffins or petroleum jelly) were dissolved in deuterated chloroform. The ERETIC factor was established using a quantification reference sample containing ethylbenzene and tetrachloronitrobenzene. The following spectral regions were integrated: MOSH δ 3.0 – 0.2 ppm and MOAH δ 9.2 - 6.5, excluding solvent signals. Validation showed a sufficient precision of the method with a coefficient of variation cosmetic products. For mineral hydrocarbon raw materials or pure mineral hydrocarbon-based cosmetic products, NMR delivers higher specificity without any sample preparation besides dilution. Our sample survey shows that previous methods may have overestimated the MOAH amount in mineral oil products and opens new paths to characterize this fraction. Therefore, the developed method can be applied for routine monitoring of consumer products aiming to minimize public health risks. PMID:28721203

  10. Evaluation of mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) in pure mineral hydrocarbon-based cosmetics and cosmetic raw materials using (1)H NMR spectroscopy.

    Science.gov (United States)

    Lachenmeier, Dirk W; Mildau, Gerd; Rullmann, Anke; Marx, Gerhard; Walch, Stephan G; Hartwig, Andrea; Kuballa, Thomas

    2017-01-01

    Mineral hydrocarbons consist of two fractions, mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH). MOAH is a potential public health hazard because it may include carcinogenic polycyclic compounds. In the present study, 400 MHz nuclear magnetic resonance (NMR) spectroscopy was introduced, in the context of official controls, to measure MOSH and MOAH in raw materials or pure mineral hydrocarbon final products (cosmetics and medicinal products). Quantitative determination (qNMR) has been established using the ERETIC methodology (electronic reference to access in vivo concentrations) based on the PULCON principle (pulse length based concentration determination). Various mineral hydrocarbons (e.g., white oils, paraffins or petroleum jelly) were dissolved in deuterated chloroform. The ERETIC factor was established using a quantification reference sample containing ethylbenzene and tetrachloronitrobenzene. The following spectral regions were integrated: MOSH δ 3.0 - 0.2 ppm and MOAH δ 9.2 - 6.5, excluding solvent signals. Validation showed a sufficient precision of the method with a coefficient of variation cosmetic products. For mineral hydrocarbon raw materials or pure mineral hydrocarbon-based cosmetic products, NMR delivers higher specificity without any sample preparation besides dilution. Our sample survey shows that previous methods may have overestimated the MOAH amount in mineral oil products and opens new paths to characterize this fraction. Therefore, the developed method can be applied for routine monitoring of consumer products aiming to minimize public health risks.

  11. Direct hydrocarbon fuel cells

    Science.gov (United States)

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  12. THERMOCHEMISTRY OF HYDROCARBON RADICALS

    Energy Technology Data Exchange (ETDEWEB)

    Kent M. Ervin, Principal Investigator

    2004-08-17

    Gas phase negative ion chemistry methods are employed to determine enthalpies of formation of hydrocarbon radicals that are important in combustion processes and to investigate the dynamics of ion-molecule reactions. Using guided ion beam tandem mass spectrometry, we measure collisional threshold energies of endoergic proton transfer and hydrogen atom transfer reactions of hydrocarbon molecules with negative reagent ions. The measured reaction threshold energies for proton transfer yield the relative gas phase acidities. In an alternative methodology, competitive collision-induced dissociation of proton-bound ion-molecule complexes provides accurate gas phase acidities relative to a reference acid. Combined with the electron affinity of the R {center_dot} radical, the gas phase acidity yields the RH bond dissociation energy of the corresponding neutral molecule, or equivalently the enthalpy of formation of the R{center_dot} organic radical, using equation: D(R-H) = {Delta}{sub acid}H(RH) + EA(R) - IE(H). The threshold energy for hydrogen abstraction from a hydrocarbon molecule yields its hydrogen atom affinity relative to the reagent anion, providing the RH bond dissociation energy directly. Electronic structure calculations are used to evaluate the possibility of potential energy barriers or dynamical constrictions along the reaction path, and as input for RRKM and phase space theory calculations. In newer experiments, we have measured the product velocity distributions to obtain additional information on the energetics and dynamics of the reactions.

  13. Membranous nephropathy following exposure to volatile hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Ehrenreich, T.; Yunis, S.L.; Churg, J.

    1977-01-01

    Excessive exposure to solvents has long been known to cause renal tubular disease in man. Recently, the occurrence of glomerular disease such as Goodpasture's syndrome with proliferative and extracapillary glomerulonephritis has been related to hydrocarbon exposure. This report concerns four patients with membranous nephropathy who had a history of prolonged exposure to a number of volatile hydrocarbons. Membranous nephropathy is a chronic renal disease involving glomeruli and occurring principally in adults. Its clinical onset is insidious and is manifested by proteinuria or edema. Proteinuria is the hallmark of the disease and may be present for many years without symptoms. It is often a slowly progressive disease. About one-fourth of the patients improve clinically and lose their proteinuria, while up to one-fourth develop renal failure. The glomerular capillary wall lesions are distinctive, contain deposits of immunoglobulin and complement considered to represent immune-complexes, and show a morphological progression from early Stage I to late Stage IV. While in most cases there is no known etiology, in some patients the disease has been deemed to be secondary to specific diseases or agents such as infections, neoplasms, or chemicals. The four cases described fall into this last category.

  14. SOLVENT EXTRACTION OF URANIUM VALUES

    Science.gov (United States)

    Feder, H.M.; Ader, M.; Ross, L.E.

    1959-02-01

    A process is presented for extracting uranium salt from aqueous acidic solutions by organic solvent extraction. It consists in contacting the uranium bearing solution with a water immiscible dialkylacetamide having at least 8 carbon atoms in the molecule. Mentioned as a preferred extractant is dibutylacetamide. The organic solvent is usually used with a diluent such as kerosene or CCl/sub 4/.

  15. Supercritical multicomponent solvent coal extraction

    Science.gov (United States)

    Corcoran, W. H.; Fong, W. S.; Pichaichanarong, P.; Chan, P. C. F.; Lawson, D. D. (Inventor)

    1983-01-01

    The yield of organic extract from the supercritical extraction of coal with larger diameter organic solvents such as toluene is increased by use of a minor amount of from 0.1 to 10% by weight of a second solvent such as methanol having a molecular diameter significantly smaller than the average pore diameter of the coal.

  16. Solvent extraction: the coordination chemistry behind extractive metallurgy.

    Science.gov (United States)

    Wilson, A Matthew; Bailey, Phillip J; Tasker, Peter A; Turkington, Jennifer R; Grant, Richard A; Love, Jason B

    2014-01-07

    The modes of action of the commercial solvent extractants used in extractive hydrometallurgy are classified according to whether the recovery process involves the transport of metal cations, M(n+), metalate anions, MXx(n-), or metal salts, MXx into a water-immiscible solvent. Well-established principles of coordination chemistry provide an explanation for the remarkable strengths and selectivities shown by most of these extractants. Reagents which achieve high selectivity when transporting metal cations or metal salts into a water-immiscible solvent usually operate in the inner coordination sphere of the metal and provide donor atom types or dispositions which favour the formation of particularly stable neutral complexes that have high solubility in the hydrocarbons commonly used in recovery processes. In the extraction of metalates, the structures of the neutral assemblies formed in the water-immiscible phase are usually not well defined and the cationic reagents can be assumed to operate in the outer coordination spheres. The formation of secondary bonds in the outer sphere using, for example, electrostatic or H-bonding interactions are favoured by the low polarity of the water-immiscible solvents.

  17. Selection and design of solvents

    DEFF Research Database (Denmark)

    Gani, Rafiqul

    . With increasing interest on issues such as waste, sustainability, environmental impact and green chemistry, the selection and design of solvents have become important problems that need to be addressed during chemical product-process design and development. Systematic methods and tools suitable for selection......Solvents are liquid solutions consisting of one or more chemicals. They have a very wide use and their use is not necessarily restricted to the process industries. This lecture will discuss the different roles and uses of solvents in chemical products and processes that manufacture them...... and design of solvents will be presented together with application examples. The selection problem is defined as finding known chemicals that match the desired functions of a solvent for a specified set of applications. The design problem is defined as finding the molecular structure (or mixture of molecules...

  18. Switchable Polarity Solvents: Are They Green?

    Science.gov (United States)

    Plaumann, Heinz

    2017-03-01

    Solvents play an incredibly important role in large scale chemical reactions. Switchable polarity solvents may prove to be a class of solvent that offers energy and material efficiencies greater than existing solvents. This paper examines such solvents and their potential in a variety of chemical reactions.

  19. Isolation and characterization of ancient hydrocarbon biomarkers from crystalline minerals

    Science.gov (United States)

    Summons, R. E.; Carrasquillo, A.; Hallmann, C.; Sherman, L. S.; Waldbauer, J. R.

    2008-12-01

    Hydrocarbon biomarker analysis is conventionally conducted on bitumen (soluble fossilized organic matter) extracted from sedimentary rocks using organic solvents. Biomarkers can also be generated by pyrolysis of kerogen (insoluble organic matter) in the same rocks. These approaches have met with much success where the organic matter has not seen significant levels of thermal metamorphism but more limited success when applied to thermally mature Archean rocks. Biomarkers have also been isolated from fluid inclusions of crystalline minerals and this approach has found wide application in petroleum exploration because of the capability of minerals that form crystals in reservoir rocks to trap organics from different episodes of fluid migration. Lastly, biogenic crystalline minerals are well known to trap organics including amino acids, fatty acids or hydrocarbons from those organisms that laid down the minerals. In fact, recent observations suggest that hydrocarbon biomarkers can be abundantly preserved in crystalline minerals where they may be protected over long periods of time and also distinguished from more recent generations of organics from endolithic organisms (modern) or anthropogenic (fossil hydrocarbon) contaminants. Here we report analyses of biomarker lipids trapped in fluid inclusions or otherwise having a "tight association" with the minerals in sedimentary rocks from Neoarchean and Paleoproterozoic successions in Australia and Southern Africa. In particular, cores recovered from the Agouron Griqualand Drilling Project contain over 2500m of well-preserved late Archean Transvaal Supergroup sediments, dating from ca. 2.67 to 2.46Ga. Bitumen extracts of samples from these strata were obtained using clean drilling, sampling and handling protocols and without overprinting with contaminant hydrocarbons. Dissolution of the mineral matrix of extracted sediments, followed by another solvent extraction, yielded a second bitumen that comprised hydrocarbons that

  20. Heat-Activated Persulfate Oxidation of Chlorinated Solvents in Sandy Soil

    Directory of Open Access Journals (Sweden)

    Jialu Liu

    2014-01-01

    Full Text Available Heat-activated persulfate oxidative treatment of chlorinated organic solvents containing chlorinated ethenes and ethanes in soil was investigated with different persulfate dosages (20 g/L, 40 g/L, and 60 g/L and different temperatures (30°C, 40°C, and 50°C. Chlorinated organic solvents removal was increased as persulfate concentration increase. The persulfate dosage of 20 g/L with the highest OE (oxidant efficiency value was economically suitable for chlorinated organic solvents removal. The increasing temperature contributed to the increasing depletion of chlorinated organic solvents. Chlorinated ethenes were more easily removed than chlorinated ethanes. Moreover, the persulfate depletion followed the pseudo-first-order reaction kinetics (kps=0.0292 [PS]0+0.0008, R2=0.9771. Heat-activated persulfate appeared to be an effective oxidant for treatment of chlorinated hydrocarbons.

  1. Handbook of organic solvent properties

    CERN Document Server

    Smallwood, Ian

    2012-01-01

    The properties of 72 of the most commonly used solvents are given, tabulated in the most convenient way, making this book a joy for industrial chemists to use as a desk reference. The properties covered are those which answer the basic questions of: Will it do the job? Will it harm the user? Will it pollute the air? Is it easy to handle? Will it pollute the water? Can it be recovered or incinerated? These are all factors that need to be considered at the early stages of choosing a solvent for a new product or process.A collection of the physical properties of most commonly used solvents, their

  2. The Solvent Selection framework: solvents for organic synthesis, separation processes and ionic-organic synthesis

    DEFF Research Database (Denmark)

    Mitrofanov, Igor; Sansonetti, Sascha; Abildskov, Jens

    2012-01-01

    problems are presented: 1) solvent selection and design for organic synthesis, 2) solvent screening and design of solvent mixtures for pharmaceutical applications and 3) ionic liquids selection and design as solvents. The application of the framework is highlighted successfully through case studies...... focusing on solvent replacement problem in organic synthesis and solvent mixture design for ibuprofen respectively....

  3. Hydrocarbon conversion catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Hoek, A.; Huizinga, T.; Maxwell, I.E.

    1989-08-15

    This patent describes a process for hydrocracking hydrocarbon oils into products of lower average molecular weight and lower average boiling point. It comprises contacting a hydrocarbon oil at a temperature between 250{sup 0}C and 500{sup 0}C and a pressure up to 300 bar in the presence of hydrogen with a catalyst consisting essentially of a Y zeolite modified to have a unit cell size below 24.35A, a water absorption capacity (at 25{sup 0}C and a rho/rho/sub o/ value of 0.2) of at least 8% by weight of the zeolite and a pore volume of at least 0.25 ml/g wherein between 10% and 60% of the total pore volume is made up of pores having a diameter of at least 8 nm; an alumina binder and at least one hydrogenation component selected from the group consisting of a Group VI metal, a Group VIII metal and mixtures thereof.

  4. Thermophysical Properties of Hydrocarbon Mixtures

    Science.gov (United States)

    SRD 4 NIST Thermophysical Properties of Hydrocarbon Mixtures (PC database for purchase)   Interactive computer program for predicting thermodynamic and transport properties of pure fluids and fluid mixtures containing up to 20 components. The components are selected from a database of 196 components, mostly hydrocarbons.

  5. Hydrocarbon Receptor Pathway in Dogs

    NARCIS (Netherlands)

    Steenbeek, F.G. van; Spee, B.; Penning, L.C.; Kummeling, A.; Gils, I.H.M.; Grinwis, G.C.M.; Leenen, D. van; Holstege, F.C.P.; Vos-Loohuis, M.; Rothuizen, J.; Leegwater, P.A.J.

    2013-01-01

    The aryl hydrocarbon receptor (AHR) mediates biological responses to toxic chemicals. An unexpected role for AHR in vascularization was suggested when mice lacking AHR displayed impaired closure of the ductus venosus after birth, as did knockout mice for aryl hydrocarbon receptor interacting protein

  6. Hydrocarbon Receptor Pathway in Dogs

    NARCIS (Netherlands)

    Steenbeek, F.G. van; Spee, B.; Penning, L.C.; Kummeling, A.; Gils, I.H.M.; Grinwis, G.C.M.; Leenen, D. van; Holstege, F.C.P.; Vos-Loohuis, M.; Rothuizen, J.; Leegwater, P.A.J.

    The aryl hydrocarbon receptor (AHR) mediates biological responses to toxic chemicals. An unexpected role for AHR in vascularization was suggested when mice lacking AHR displayed impaired closure of the ductus venosus after birth, as did knockout mice for aryl hydrocarbon receptor interacting

  7. Practical Approaches to Green Solvents

    National Research Council Canada - National Science Library

    Joseph M. DeSimone

    2002-01-01

    Solvents are widely used in commercial manufacturing and service industries. Despite abundant precaution, they inevitably contaminate our air, land, and water because they are difficult to contain and recycle...

  8. Hansen Cleaning Solvent Research Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Environmental regulation will force current baseline  precision cleaning solvent (AK-225) to be phased out starting 2015. We plan to develop  a new...

  9. Applied biotransformations in green solvents.

    Science.gov (United States)

    Hernáiz, María J; Alcántara, Andrés R; García, José I; Sinisterra, José V

    2010-08-16

    The definite interest in implementing sustainable industrial technologies has impelled the use of biocatalysts (enzymes or cells), leading to high chemo-, regio- and stereoselectivities under mild conditions. As usual substrates are not soluble in water, the employ of organic solvents is mandatory. We will focus on different attempts to combine the valuable properties of green solvents with the advantages of using biocatalysts for developing cleaner synthetic processes.

  10. Study of ionic equilibria of indotricarbocyanines in aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Dyadyusha, G.G.; Ishchenko, A.A.; Derevyanko, N.A.; Tolmachev, A.I.

    1982-05-01

    Study of the equilibria in nonpolar solvents is very complicated by the poor solubility of the salt-like dyes. Indotricarbocyanines I and II were found to be fairly soluble in aromatic hydrocarbons for solving these problems by means of electronic spectra. In the present work, their absorption spectra were studied in benzene, toluene, and m-xylene (the absorption spectra were measured on the SF-8 spectrophotometer). It was shown that the dyes studied in these solvents have spectral bands of unusual form of polymethine dyes. At the long wave edge of the spectra of indotricarbocyanines, a distinct band appears, whose intensity is very dependent on the nature of the anion. In the case of perchlorate I, it has a lower intensity, and in the case of iodide II, the intensity is higher.

  11. Progress towards a process for the recycling of nickel metal hydride electric cells using a deep eutectic solvent

    Directory of Open Access Journals (Sweden)

    Mark R.StJ. Foreman

    2016-12-01

    Full Text Available Solvent extraction experiments relating to the recycling of the transition metals and lanthanides in nickel metal hydride cells are presented. The metal extraction is occurring from a deep eutectic solvent which is formed from chemicals suitable for use in food and related products. While it has been shown that the water content of the DES has a large effect on the extraction of transition metals by a mixture of chloride ionic liquid (Aliquat 336 and an aromatic solvent, the water content has a smaller effect on the solvent extraction of lanthanides with a solution of di(2-ethylhexyl hydrogen phosphate (DEHPA in a saturated aliphatic hydrocarbon. This study suggests that an industrial scale solvent extraction process for the recycling of metals from nickel hydride electrical cells will be feasible.

  12. Solvent/Non-Solvent Sintering To Make Microsphere Scaffolds

    Science.gov (United States)

    Laurencin, Cato T.; Brown, Justin L.; Nair, Lakshmi

    2011-01-01

    A solvent/non-solvent sintering technique has been devised for joining polymeric microspheres to make porous matrices for use as drug-delivery devices or scaffolds that could be seeded with cells for growing tissues. Unlike traditional sintering at elevated temperature and pressure, this technique is practiced at room temperature and pressure and, therefore, does not cause thermal degradation of any drug, protein, or other biochemical with which the microspheres might be loaded to impart properties desired in a specific application. Also, properties of scaffolds made by this technique are more reproducible than are properties of comparable scaffolds made by traditional sintering. The technique involves the use of two miscible organic liquids: one that is and one that is not a solvent for the affected polymer. The polymeric microspheres are placed in a mold having the size and shape of the desired scaffold, then the solvent/non-solvent mixture is poured into the mold to fill the void volume between the microspheres, then the liquid mixture is allowed to evaporate. Some of the properties of the resulting scaffold can be tailored through choice of the proportions of the liquids and the diameter of the microspheres.

  13. Evolution of a degradative bacterial consortium during the enrichment of naphtha solvent.

    Science.gov (United States)

    Cavalca, L; Confalonieri, A; Larcher, S; Andreoni, V

    2000-06-01

    A microbial mixed culture able to degrade naphtha solvent, a model of hydrocarbon aromatic mixture, was isolated from a hydrocarbon-polluted soil. Composition of the population was monitored by phenotypic and molecular methods applied on soil DNA, on whole enrichment culture DNA, and on 85 isolated strains. Strains were characterized for their 16S rDNA restriction profiles and for their random amplified polymorphic DNA profiles. Catabolic capabilities were monitored by phenotypic traits and by PCR assays for the presence of the catabolic genes methyl mono-oxygenase ( xylA, M), catechol 2,3 dioxygenase (xylE) and toluene dioxygenase (todC1) of TOL and TOD pathways. Different haplotypes belonging to Pseudomonas putida, Ps. aureofaciens and Ps. aeruginosa were found to degrade aromatic compounds and naphtha solvent. The intrinsic catabolic activity of the microbial population of the polluted site was detected by PCR amplification of the xylE gene directly from soil DNA.

  14. Optimization and determination of polycyclic aromatic hydrocarbons in biochar-based fertilizers.

    Science.gov (United States)

    Chen, Ping; Zhou, Hui; Gan, Jay; Sun, Mingxing; Shang, Guofeng; Liu, Liang; Shen, Guoqing

    2015-03-01

    The agronomic benefit of biochar has attracted widespread attention to biochar-based fertilizers. However, the inevitable presence of polycyclic aromatic hydrocarbons in biochar is a matter of concern because of the health and ecological risks of these compounds. The strong adsorption of polycyclic aromatic hydrocarbons to biochar complicates their analysis and extraction from biochar-based fertilizers. In this study, we optimized and validated a method for determining the 16 priority polycyclic aromatic hydrocarbons in biochar-based fertilizers. Results showed that accelerated solvent extraction exhibited high extraction efficiency. Based on a Box-Behnken design with a triplicate central point, accelerated solvent extraction was used under the following optimal operational conditions: extraction temperature of 78°C, extraction time of 17 min, and two static cycles. The optimized method was validated by assessing the linearity of analysis, limit of detection, limit of quantification, recovery, and application to real samples. The results showed that the 16 polycyclic aromatic hydrocarbons exhibited good linearity, with a correlation coefficient of 0.996. The limits of detection varied between 0.001 (phenanthrene) and 0.021 mg/g (benzo[ghi]perylene), and the limits of quantification varied between 0.004 (phenanthrene) and 0.069 mg/g (benzo[ghi]perylene). The relative recoveries of the 16 polycyclic aromatic hydrocarbons were 70.26-102.99%.

  15. Lignin Peroxidase Oxidation of Aromatic Compounds in Systems Containing Organic Solvents

    OpenAIRE

    Vazquez-Duhalt, Rafael; Westlake, Donald W. S.; Fedorak, Phillip M.

    1994-01-01

    Lignin peroxidase from Phanerochaete chrysosporium was used to study the oxidation of aromatic compounds, including polycyclic aromatic hydrocarbons and heterocyclic compounds, that are models of moieties of asphaltene molecules. The oxidations were done in systems containing water-miscible organic solvents, including methanol, isopropanol, N, N-dimethylformamide, acetonitrile, and tetrahydrofuran. Of the 20 aromatic compounds tested, 9 were oxidized by lignin peroxidase in the presence of hy...

  16. Ultrasound Energy Effect on Solvent Extraction of Amaranth Seed Oil

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Won Il; Chung, Ki Won; Lee, Seung Bum; Hong, In Kwon [Department of Chemical Engineering, Dankook University, Seoul (Korea); Park, Kyung Ai [Seoul Metropolitan Government Institute of Health and Environment, Seoul (Korea)

    2001-05-01

    Ultrasonic energy has been widely applied to cleaning, medical appliances, extraction, etc. And ultrasonic energy can be applied to solvent extraction of plant oil from amaranth seed. Amaranth seed oil contains small amount of squalene. Squalene is polyunsaturated branched hydrocarbon, which is an essential part of the human body. In this study, the seed oil was extracted from amaranth seed by ultrasonic solvent extraction process. Ultrasonic irradiation time was 1, 3 ,5, 10, 20 and 30 min and extraction temperature was 20, 30, and 40 degree C. And ultrasonic power was 390 W and 520 W. The extracted amounts of amaranth seed oil and squalene were increased with the increase of ultrasonic power and irradiation time. Using ultrasonic energy in solvent extraction, extraction time was very shorten. The optimum extraction temperature was 30 degree C, it was caused that ultrasonic energy effects were increased in the matters of low temperature. The maximum extracted amount of amaranth seed oil was 0.746 g and squalene was 37.54 mg per 10 g amaranth seed at 30 degree C. 10 refs., 8 figs., 1 tab.

  17. Handbook of green chemistry, green solvents, supercritical solvents

    CERN Document Server

    Anastas, Paul T; Jessop, Philip G

    2014-01-01

    Green Chemistry is a vitally important subject area in a world where being as green and environmentally sound as possible is no longer a luxury but a necessity. Its applications include the design of chemical products and processes that help to reduce or eliminate the use and generation of hazardous substances. The Handbook of Green Chemistry comprises 12 volumes, split into subject-specific sets as follows: Set I: Green Catalysis Set II: Green Solvents Volume 4: Supercritical Solvents Volume 5: Reactions in Water Volume 6: Ionic Liquids

  18. Computer Aided Solvent Selection and Design Framework

    DEFF Research Database (Denmark)

    Mitrofanov, Igor; Conte, Elisa; Abildskov, Jens

    , millions of tons solvents have to be wasted every year [2]. Therefore, it becomes important to minimize and optimize the use of organic solvents as much as possible, to satisfy the “Green Chemistry Principles” [3]. Another challenge is that currently solvent selection relies very much on previous...... is to develop a systematic framework and implement it as software for selection and design of solvents for many applications including organic synthesis, complex reaction systems and solvent-based separations. The solvent selection framework is based on a combination of knowledge from industrial practice...... identification of solvent candidates using special software ProCAMD and ProPred, which are the implementations of computer-aided molecular techniques. The second consists of assigning the RS-indices following the reaction–solvent and then consulting the known solvent database and identifying the set of solvents...

  19. Method for predicting fouling tendency of a hydrocarbon-containing feedstock

    Science.gov (United States)

    Schabron, John F; Rovani, Jr., Joseph F

    2013-07-23

    Disclosed herein is a method involving the steps of (a) precipitating an amount of asphaltenes from a liquid sample of a first hydrocarbon-containing feedstock having solvated asphaltenes therein with one or more first solvents in a column; (b) determining one or more solubility characteristics of the precipitated asphaltenes; (c) analyzing the one or more solubility characteristics of the precipitated asphaltenes; and (d) correlating a measurement of feedstock fouling tendency for the first hydrocarbon-containing feedstock sample with a mathematical parameter derived from the results of analyzing the one or more solubility characteristics of the precipitated asphaltenes.

  20. A novel zeolite process for clean end use of hydrocarbon products

    Energy Technology Data Exchange (ETDEWEB)

    Keskinen, K.M. [Neste Oy, Porvoo (Finland). Technology Centre

    1996-12-31

    In recent years zeolites such as ZSM-5 have attracted considerable interest for the catalysis of a wide range of hydrocarbon transformations. A novel process developed by Neste converts light olefins to higher molecular weight hydrocarbon products. A wide range of high quality diesel, solvents and lube oils can be produced by the new NESKO process. Hydrotreated products have excellent properties; negligible sulphur or nitrogen compounds, very low aromatic content and pour point lower than -50 deg C. Proprietary technology is used in this olefin oligomerization process. (author) (7 refs.)

  1. Pressurized solvent extraction of environmental organic compounds in soils using a supercritical fluid extractor

    Energy Technology Data Exchange (ETDEWEB)

    Li, K.; Landriault, M.; Fingas, M. [Emergencies Science Division, Environmement Canada, Environment Technology Centre, Ontario (Canada); Llompart, M. [Universidad de Santiago de Compostela (Spain). Dept. de Quimica Analitica, Nutricieon y bromatologia, Facultad de Quimica

    1998-11-01

    The applicability of pressurised solvent extraction (PSE) for the quantitative extraction of different of semi-volatiles, including polycyclic aromatic hydrocarbons (PAHs), phenols, polychlorinated biphenyls (PCBs) and total petroleum hydrocarbons have been evaluated. For this study a conventional supercritical fluid extraction (SFE) system, the Suprex SFE/50 was adapted to function as a pressurised solvent extraction system. Solid samples were weighed into the SFE thimble and extracted using conventional extraction solvents instead of superficial carbon dioxide. Parameters such as extraction temperature and effect of modifiers were investigated. Although limited by the 150 deg. C maximum oven temperature, it was found effective extraction could still be carried out in less than 25 min for all the compounds studied. The technique was applied to different real matrices contaminated with hydrocarbons, PAHs and phenols. Validations of the technique were performed using standard reference materials. Recoveries for these matrices were good (> 75 %) and precision was generally less than a 10 % RSD. Extensive comparison of this technique with sonication and with microwave assisted extraction (MAE) were made, and recoveries were found to be comparable to MAE and superior to sonication. (authors) 15 refs.

  2. Glycerol based solvents: synthesis, properties and applications

    OpenAIRE

    García, José I.; García-Marín, Héctor; Pires, Elísabet

    2014-01-01

    The most recent advances in the use of glycerol and glycerol derivatives as solvents are reviewed. There are an increasing number of examples of the use of glycerol itself as a reaction medium, solvent-reagent or a dispersive medium for a large variety of applications. In the case of glycerol derivatives, new synthetic methods, physico-chemical properties and application examples as solvents are revised. Recent studies in the field of solvent classification, as well as solvent substitution is...

  3. Multiple sclerosis and organic solvents

    DEFF Research Database (Denmark)

    Mortensen, J T; Brønnum-Hansen, Henrik; Rasmussen, K

    1998-01-01

    We investigated a possible causal relation between exposure to organic solvents in Danish workers (housepainters, typographers/printers, carpenters/cabinetmakers) and onset of multiple sclerosis. Data on men included in the Danish Multiple Sclerosis Register (3,241 men) were linked with data from......, and butchers. Over a follow-up period of 20 years, we observed no increase in the incidence of multiple sclerosis among men presumed to be exposed to organic solvents. It was not possible to obtain data on potential confounders, and the study design has some potential for selection bias. Nevertheless......, the study does not support existing hypotheses regarding an association between occupational exposure to organic solvents and multiple sclerosis....

  4. Hydrocarbon Leak Detection Sensor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — FTT is proposing the development of a sensor to detect the presence of hydrocarbons in turbopump Inter-Propellant Seals (IPS). The purpose of the IPS is to prevent...

  5. Growth of hydrocarbon utilizing microorganisms

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Mavinkurve, S.

    Two isolates from marine mud having broad spectrum hydrocarbon utilizing profile were identified as Arthrobacter simplex and Candida tropicalis.Both the organisms grew exponentially on crude oil. The cell yield of the organisms was influenced...

  6. Bioassay of polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Van Kirk, E.A.

    1980-08-01

    A positive relationship was found between the photodynamic activity of 24 polycyclic aromatic hydrocarbons versus published results on the mutagenicity, carcinogenicity, and initiation of unscheduled DNA synthesis. Metabolic activation of benzo(a)pyrene resulted in detection of increased mutagenesis in Paramecium tetraurelia as found also in the Ames Salmonella assay. The utility of P. tetraurelia as a biological detector of hazardous polycyclic aromatic hydrocarbons is discussed.

  7. Aliphatic hydrocarbons of the fungi.

    Science.gov (United States)

    Weete, J. D.

    1972-01-01

    Review of studies of aliphatic hydrocarbons which have been recently detected in the spores of phytopathogenic fungi, and are found to be structurally very similar to the alkanes of higher plants. It appears that the hydrocarbon components of the few mycelial and yeast forms reported resemble the distribution found in bacteria. The occurence and distribution of these compounds in the fungi is discussed. Suggested functional roles of fungal spore alkanes are presented.

  8. LIQUID HYDROCARBON FUEL CELL DEVELOPMENT.

    Science.gov (United States)

    A compound anode consists of a reforming catalyst bed in direct contact with a palladium-silver fuel cell anode. The objective of this study was to...prove the feasibility of operating a compound anode fuel cell on a liquid hydrocarbon and to define the important parameters that influence cell...performance. Both reformer and fuel cell tests were conducted with various liquid hydrocarbon fuels. Included in this report is a description of the

  9. Treatment of hydrocarbon contamination under flow through conditions by using magnetite catalyzed chemical oxidation.

    Science.gov (United States)

    Usman, M; Faure, P; Lorgeoux, C; Ruby, C; Hanna, K

    2013-01-01

    Soil pollution by hydrocarbons (aromatic and aliphatic hydrocarbons) is a major environmental issue. Various treatments have been used to remove them from contaminated soils. In our previous studies, the ability of magnetite has been successfully explored to catalyze chemical oxidation for hydrocarbon remediation in batch slurry system. In the present laboratory study, column experiments were performed to evaluate the efficiency of magnetite catalyzed Fenton-like (FL) and activated persulfate (AP) oxidation for hydrocarbon degradation. Flow-through column experiments are intended to provide a better representation of field conditions. Organic extracts isolated from three different soils (an oil-contaminated soil from petrochemical industrial site and two soils polluted by polycyclic aromatic hydrocarbon (PAH) originating from coking plant sites) were spiked on sand. After solvent evaporation, spiked sand was packed in column and was subjected to oxidation using magnetite as catalyst. Oxidant solution was injected at a flow rate of 0.1 mL min(-1) under water-saturated conditions. Organic analyses were performed by GC-mass spectrometry, GC-flame ionization detector, and micro-Fourier transform infrared spectroscopy. Significant abatement of both types of hydrocarbons (60-70 %) was achieved after chemical oxidation (FL and AP) of organic extracts. No significant by-products were formed during oxidation experiment, underscoring the complete degradation of hydrocarbons. No selective degradation was observed for FL with almost similar efficiency towards all hydrocarbons. However, AP showed less reactivity towards higher molecular weight PAHs and aromatic oxygenated compounds. Results of this study demonstrated that magnetite-catalyzed chemical oxidation can effectively degrade both aromatic and aliphatic hydrocarbons (enhanced available contaminants) under flow-through conditions.

  10. J-aggregation, its impact on excited state dynamics and unique solvent effects on macroscopic assembly of a core-substituted naphthalenediimide

    KAUST Repository

    Kar, Haridas

    2015-03-12

    Herein we reveal a straightforward supramolecular design for the H-bonding driven J-aggregation of an amine-substituted cNDI in aliphatic hydrocarbons. Transient absorption spectroscopy reveals sub-ps intramolecular electron transfer in isolated NDI molecules in a THF solution followed by a fast recombination process, while a remarkable extension of the excited state lifetime by more than one order of magnitude occurred in methylcyclohexane likely owing to an increased charge-separation as a result of better delocalization of the charge-separated states in J-aggregates. We also describe unique solvent-effects on the macroscopic structure and morphology. While J-aggregation with similar photophysical characteristics was noticed in all the tested aliphatic hydrocarbons, the morphology strongly depends on the “structure” of the solvents. In linear hydrocarbons (n-hexane, n-octane, n-decane or n-dodecane), formation of an entangled fibrillar network leads to macroscopic gelation while in cyclic hydrocarbons (methylcyclohexane or cyclohexane) although having a similar polarity, the cNDI exhibits nanoscale spherical particles. These unprecedented solvent effects were rationalized by establishing structure-dependent specific interactions of the solvent molecules with the cNDI which may serve as a general guideline for solvent-induced morphology-control of structurally related self-assembled materials.

  11. HYDROCARBONS RESERVES IN VENEZUELA

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Cruz, D.J.

    2007-07-01

    Venezuela is an important player in the energy world, because of its hydrocarbons reserves. The process for calculating oil and associated gas reserves is described bearing in mind that 90% of the gas reserves of Venezuela are associated to oil. Likewise, an analysis is made of the oil reserves figures from 1975 to 2003. Reference is also made to inconsistencies found by international experts and the explanations offered in this respect by the Ministry of Energy and Petroleum (MENPET) and Petroleos de Venezuela (PDVSA) regarding the changes that took place in the 1980s. In turn, Hubbert's Law is explained to determine peak production of conventional oil that a reservoir or field will reach, as well as its relationship with remaining reserves. Emphasis is placed on the interest of the United Nations on this topic. The reserves of associated gas are presented along with their relationship with the different crude oils that are produced and with injected gas, as well as with respect to the possible changes that would take place in the latter if oil reserves are revised. Some recommendations are submitted so that the MENPET starts preparing the pertinent policies ruling reserves. (auth)

  12. Evaluation of hydrocarbon potential

    Energy Technology Data Exchange (ETDEWEB)

    Cashman, P.H.; Trexler, J.H. Jr. [Univ. of Nevada, Reno, NV (United States)

    1992-09-30

    Task 8 is responsible for assessing the hydrocarbon potential of the Yucca Mountain vincinity. Our main focus is source rock stratigraphy in the NTS area in southern Nevada. (In addition, Trexler continues to work on a parallel study of source rock stratigraphy in the oil-producing region of east central Nevada, but this work is not funded by Task 8.) As a supplement to the stratigraphic studies, we are studying the geometry and kinematics of deformation at NTS, particularly as these pertain to reconstructing Paleozoic stratigraphy and to predicting the nature of the Late Paleozoic rocks under Yucca Mountain. Our stratigraphic studies continue to support the interpretation that rocks mapped as the {open_quotes}Eleana Formation{close_quotes} are in fact parts of two different Mississippian units. We have made significant progress in determining the basin histories of both units. These place important constraints on regional paleogeographic and tectonic reconstructions. In addition to continued work on the Eleana, we plan to look at the overlying Tippipah Limestone. Preliminary TOC and maturation data indicate that this may be another potential source rock.

  13. Aggregation behavior modulation of 1-dodecyl-3-methylimidazolium bromide by organic solvents in aqueous solution.

    Science.gov (United States)

    Wang, Jianji; Zhang, Lamei; Wang, Huiyong; Wu, Changzeng

    2011-05-05

    Material preparation in ionic liquids and environmental pollution control by ionic liquids are often closely dependent on the aggregation behavior of ionic liquids in solution. In the present work, conductivity, fluorescence probe, and dynamic light scattering techniques have been used to study the effect of organic solvents on the aggregation behavior of 1-dodecyl-3-methylimidazolium bromide in water. It was shown that the critical aggregation concentration (CAC), the ionization degree of the aggregates (α), and the standard Gibbs energy of aggregation (ΔG(m)°) of the ionic liquid increase, while its aggregation number (N(agg)) and aggregates' size decrease with increasing concentration of organic additives in water. These results have been discussed from the favorable interactions of alkyl chain of the ionic liquid with the mixed solvents. It is suggested that the solvophobic parameter, characterized quantitatively by Gibbs energy of transfer of hydrocarbon from gas into a given solvent, can be used to account for the effect of organic additives on the formation and growth of the ionic liquid aggregates in water. Aggregation behavior of ionic liquids in aqueous organic solutions can be modulated simply by the solvophobic parameters of hydrocarbon in the mixed solvents.

  14. Which solvent for olfactory testing?

    Science.gov (United States)

    Philpott, C M; Goodenough, P C; Wolstenholme, C R; Murty, G E

    2004-12-01

    The physical properties of any carrier can deteriorate over time and thus alter the results in any olfactory test. The aim of this study was to evaluate clinically potential solvents as a clean odourless carrier for olfactory testing. Sweet almond oil, pure coconut oil, pure peach kernel oil, dipropylene glycol, monopropylene glycol, mineral oil and silicone oil were studied. The experimentation was conducted in two parts. First, an olfactory device was used to conduct air through the solvents on a weekly basis using a cohort of six volunteers to assess the perceived odour of each solvent at weekly intervals. Secondly a cross-reference test was performed using small bottled solutions of phenylethyl-alcohol and 1-butanol in 10-fold dilutions to compare any perceived difference in concentrations over a period of 8 weeks. We concluded that mineral oil is the most suitable carrier for the purpose of olfactory testing, possessing many desirable characteristics of an olfactory solvent, and that silicone oil may provide a suitable alternative for odorants with which it is miscible.

  15. 魏氏兒童智力量表第四版建構內涵之探討 What Does the WISC-IV Measure? Validation of the Scoring and CHC-based Interpretative Approaches

    Directory of Open Access Journals (Sweden)

    陳心怡 Hsin-Yi Chen

    2009-09-01

    Full Text Available 本研究目的在分析魏氏兒童智力量表第四版(WISC-IV)所測量之認知內涵。根據臺灣標準化樣本(n = 968),研究者以高階驗證性因素分析針對「WISC-IV現行計分依據之四因素模式」及「Cattell-Horn-Carroll(CHC)認知理論模式」兩種架構進行系列性效度驗證。主要研究發現為:一、不同年齡組兒童展現一致的WISC-IV 建構內涵,亦即研究中報告的建構解釋方式適用於6-16 歲之各年齡層兒童;二、「WISC-IV 四因素模式」及「CHC 認知理論模式」二者均為合理且具意義之詮釋方式,且二架構所解釋到之分數變異量相當一致。其中,高階g因素約解釋2/3 之共同變異量,而其他初階因素則解釋到1/3 之共同變異量;三、在CHC 認知理論模式下,WISC-IV 測量之認知能力有結晶智力(Gc),視覺處理(Gv),流體推理(Gf),短期/工作記憶(Gsm)及處理速度(Gs)。值得注意的是,不論將Gf 與Gv 依CHC 理論分開解釋,或容許二者結合成WISC-IV 四因素內之知覺推理因素(PRI),兩種建構在本研究中均獲支持為可行詮釋方式;四、不論採哪一種理論模式,算術分測驗均明顯呈現跨因素負荷量(split loadings)。算術分測驗測量到多種內涵,其中包括流體推理能力(Gf),短期/工作記憶(Gsm),以及結晶智力(Gc)。 The validity of WISC-IV current four-factor scoring structure and the Cattell-Horn-Carroll (CHC theory-based models of the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV were investigated via the application of higher-order confirmatory factor analyses of scores from the Taiwan WISC-IV standardized sample (n = 968. Results reveal that the WISC-IV measures the same construct across ages, the resulting interpretation could be applied to children with various age levels. Both the four-factor structure and CHC

  16. A Combustion Chemistry Analysis of Carbonate Solvents in Li-Ion Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Harris, S J; Timmons, A; Pitz, W J

    2008-11-13

    Under abusive conditions Li-ion batteries can rupture, ejecting electrolyte and other flammable gases. In this paper we consider some of the thermochemical properties of these gases that will determine whether they ignite and how energetically they burn. We show that flames of carbonate solvents are fundamentally less energetic than those of conventional hydrocarbons. An example of this difference is given using a recently developed mechanism for dimethyl carbonate (DMC) combustion, where we show that a diffusion flame burning DMC has only half the peak energy release rate of an analogous propane flame. We find a significant variation among the carbonate solvents in the factors that are important to determining flammability, such as combustion enthalpy and vaporization enthalpy. This result suggests that thermochemical and kinetic factors might well be considered when choosing solvent mixtures.

  17. Evaluation of mineral oil saturated hydrocarbons (MOSH and mineral oil aromatic hydrocarbons (MOAH in pure mineral hydrocarbon-based cosmetics and cosmetic raw materials using 1H NMR spectroscopy [version 1; referees: 2 approved, 1 approved with reservations

    Directory of Open Access Journals (Sweden)

    Dirk W. Lachenmeier

    2017-05-01

    Full Text Available Mineral hydrocarbons consist of two fractions, mineral oil saturated hydrocarbons (MOSH and mineral oil aromatic hydrocarbons (MOAH. MOAH is a potential public health hazard because it may include carcinogenic polycyclic compounds. In the present study, 400 MHz nuclear magnetic resonance (NMR spectroscopy was introduced, in the context of official controls, to measure MOSH and MOAH in raw materials or pure mineral hydrocarbon final products (cosmetics and medicinal products. Quantitative determination (qNMR has been established using the ERETIC methodology (electronic reference to access in vivo concentrations based on the PULCON principle (pulse length based concentration determination. Various mineral hydrocarbons (e.g., white oils, paraffins or petroleum jelly were dissolved in deuterated chloroform. The ERETIC factor was established using a quantification reference sample containing ethylbenzene and tetrachloronitrobenzene. The following spectral regions were integrated: MOSH δ 3.0 – 0.2 ppm and MOAH δ 9.2 - 6.5, excluding solvent signals. Validation showed a sufficient precision of the method with a coefficient of variation <6% and a limit of detection <0.1 g/100 g. The applicability of the method was proven by analysing 27 authentic samples with MOSH and MOAH contents in the range of 90-109 g/100 g and 0.02-1.10 g/100 g, respectively. It is important to distinguish this new NMR-approach from the hyphenated liquid chromatography-gas chromatography methodology previously used to characterize MOSH/MOAH amounts in cosmetic products. For mineral hydrocarbon raw materials or pure mineral hydrocarbon-based cosmetic products, NMR delivers higher specificity without any sample preparation besides dilution. Our sample survey shows that previous methods may have overestimated the MOAH amount in mineral oil products and opens new paths to characterize this fraction. Therefore, the developed method can be applied for routine monitoring of consumer

  18. Evaluation of mineral oil saturated hydrocarbons (MOSH and mineral oil aromatic hydrocarbons (MOAH in pure mineral hydrocarbon-based cosmetics and cosmetic raw materials using 1H NMR spectroscopy [version 2; referees: 3 approved

    Directory of Open Access Journals (Sweden)

    Dirk W. Lachenmeier

    2017-08-01

    Full Text Available Mineral hydrocarbons consist of two fractions, mineral oil saturated hydrocarbons (MOSH and mineral oil aromatic hydrocarbons (MOAH. MOAH is a potential public health hazard because it may include carcinogenic polycyclic compounds. In the present study, 400 MHz nuclear magnetic resonance (NMR spectroscopy was introduced, in the context of official controls, to measure MOSH and MOAH in raw materials or pure mineral hydrocarbon final products (cosmetics and medicinal products. Quantitative determination (qNMR has been established using the ERETIC methodology (electronic reference to access in vivo concentrations based on the PULCON principle (pulse length based concentration determination. Various mineral hydrocarbons (e.g., white oils, paraffins or petroleum jelly were dissolved in deuterated chloroform. The ERETIC factor was established using a quantification reference sample containing ethylbenzene and tetrachloronitrobenzene. The following spectral regions were integrated: MOSH δ 3.0 – 0.2 ppm and MOAH δ 9.2 - 6.5, excluding solvent signals. Validation showed a sufficient precision of the method with a coefficient of variation <6% and a limit of detection <0.1 g/100 g. The applicability of the method was proven by analysing 27 authentic samples with MOSH and MOAH contents in the range of 90-109 g/100 g and 0.02-1.10 g/100 g, respectively. It is important to distinguish this new NMR-approach from the hyphenated liquid chromatography-gas chromatography methodology previously used to characterize MOSH/MOAH amounts in cosmetic products. For mineral hydrocarbon raw materials or pure mineral hydrocarbon-based cosmetic products, NMR delivers higher specificity without any sample preparation besides dilution. Our sample survey shows that previous methods may have overestimated the MOAH amount in mineral oil products and opens new paths to characterize this fraction. Therefore, the developed method can be applied for routine monitoring of consumer

  19. Polycyclic Aromatic Hydrocarbons

    Science.gov (United States)

    Salama, Farid

    2010-01-01

    Carbonaceous materials play an important role in space. Polycyclic Aromatic Hydrocarbons (PAHs) are a ubiquitous component of the carbonaceous materials. PAHs are the best-known candidates to account for the IR emission bands. They are also thought to be among the carriers of the diffuse interstellar absorption bands (DIBs). PAH ionization states reflect the ionization balance of the medium while PAH size, composition, and structure reflect the energetic and chemical history of the medium. A major challenge is to reproduce in the laboratory the physical conditions that exist in the emission and absorption interstellar zones. The harsh physical conditions of the ISM -low temperature, collisionless, strong UV radiation fields- are simulated in the laboratory by associating a molecular beam with an ionizing discharge to generate a cold plasma expansion. PAH ions and radicals are formed from the neutral precursors in an isolated environment at low temperature and probed with high-sensitivity cavity ringdown spectroscopy in the NUV-NIR range. Carbon nanoparticles are also formed during the short residence time of the precursors in the plasma and are characterized with time-offlight mass spectrometry. These experiments provide unique information on the spectra of large carbonaceous molecules and ions in the gas phase that can now be directly compared to interstellar and circumstellar observations (IR emission bands, DIBs, extinction curve). These findings also hold great potential for understanding the formation process of interstellar carbonaceous grains. We will review recent progress in the experimental and theoretical studies of PAHs, compare the laboratory data with astronomical observations and discuss the global implications.

  20. A method for removing aromatic hydrocarbons from liquid n-paraffins

    Energy Technology Data Exchange (ETDEWEB)

    Gayle, A.A.; Pavlyuk, N.F.; Proskuryakov, V.A.; Semenov, L.V.; Zakhrov, A.P.

    1982-01-01

    In the known method for removing aromatic hydrocarbons from liquid n-paraffins through liquid extraction by a selective solvent, in order to increase the output of the paraffins methoxyacetonitrile (I) is used as the selective solvent. The advantages of the extraction process using I are high output and quality of the purified paraffins and the possibility of using series produced extractors of medium effectiveness. The high selectivity of I relative to aromatic hydrocarbons, unlike low selective acetone in the known method and its high density (1.032) as compared with acetone (0.790) provide for effective mass exchange in industrial performance of the process. The regeneration of I from the extraction phase may be accomplished through rectification. In an example of single stage isolation of mixtures of n-tetradecane with 1,2,4,5-tetramethylbenzene and 1-methylnaphthaline (a temperature of 30 degrees, a ratio of solvent to raw material of 3, an aromatic hydrocarbon content in the mixture of 1.0 percent) showed the following.

  1. Saturated hydrocarbon content in olive fruits and crude olive pomace oils.

    Science.gov (United States)

    Gómez-Coca, Raquel B; Pérez-Camino, María Del Carmen; Moreda, Wenceslao

    2016-01-01

    Olive fruits contain an n-alkane series of saturated hydrocarbons mainly in the pulp. Lower amounts of a complex mixture of paraffins, unresolved by gas chromatography (UCM--unresolved complex mixture), have been found in cuticle, stone (woody shell and seed), olive leaves, and talc used as an aid to olive oil extraction. The amounts of both kinds of hydrocarbons are related to the olive cultivar and are transferred to oils in a proportion depending on the oil-obtaining process (centrifugation or solvent extraction). In olive oil obtained by centrifugation, only n-alkanes were detected. However, in olive oil extracted by second centrifugation, small amounts of UCM paraffins were detected together with the n-alkanes. Olive pomace oils showed a very variable content of both types of hydrocarbons according to the different obtaining process, such as double centrifugation, solvent extraction or centrifugation followed by solvent extraction. 'White mineral oil' used in oil extraction machinery is the source of the high concentrations of UCM paraffins found in some olive and olive pomace oils. In the case of second centrifugation olive oil, a maximum limit of 50 mg kg(-1) of UCM is suggested, whereas in the case of crude olive pomace oil, it amounts to 250 mg kg(-1) plus an additional minimum of 1.0 for the n-alkanes/UCM ratio.

  2. Methods for analysis of trace levels (. mu. g/kg) of hydrocarbons in the marine environment

    Energy Technology Data Exchange (ETDEWEB)

    Chesler, S.N.; Gump, B.H.; Hertz, H.S.; May, W.E.; Wise, S.A.

    1977-01-01

    The use of dynamic headspace sampling and coupled-column LC either alone or in combination offers a number of advantages over most of the current sample preparation techniques for ..mu..g/kg hydrocarbon analysis of marine sediment and water samples. These techniques require minimal sample handling, thereby reducing the risks of loss of sample components and of possible contamination. Volatile components of the sample are efficiently separated from the matrix in a closed system and collected in a concentrated form that is free from large amounts of solvents and ready for GC/GC-MS analysis. A significant advantage derives from the fact that water is the only solvent needed for the preparation of water and sediment samples. The use of hydrocarbon-free water reduces opportunities for contamination of the sample by fossil hydrocarbons. Tissue samples must be stripped of biogenic nonhydrocarbon constituents prior to GC/GC-MS analysis. However, low blanks (< 20 ..mu..g/kg) can be obtained if special care is used in distillation of solvents and preparation of columns used in the LC clean-up.

  3. Modified Hyperbranched Polyglycerol as Dispersant for Size Control and Stabilization of Gold Nanoparticles in Hydrocarbons

    Science.gov (United States)

    Shen, Yanyu; He, Guijin; Guo, Yongsheng; Xie, Hujun; Fang, Wenjun

    2017-09-01

    Hyperbranched polyglycerol (HPG) is modified with dodecanethiol (DS) via the "thiol-ene" click reaction to obtain an amphiphilic product DSHPG. The molecular structures of DSHPG samples are characterized by NMR, FTIR, and GPC, and the thermal behaviors are characterized by DSC and TGA. Gold nanoparticles (Au NPs) are prepared with DSHPG as the stabilizer and surface-modification reagent. The size of Au NPs can be tuned by changing the molecular weight of HPG. It is observed that the HPG molecular weights of 1123, 3826, and 55,075 lead to the NP diameters of 4.1 nm for Au@DSHPG-1, 9.7 nm for Au@DSHPG-2, and 15.1 nm for Au@DSHPG-3, respectively. The morphology and size of Au NPs are characterized by TEM and DLS. Especially, the dispersion abilities of Au NPs in different pure solvents and co-solvent mixtures are investigated. The long alkyl chains on DSHPG give the ability of Au NPs to be well dispersed in nonpolar solvents. Hydrocarbon-based nanofluids can be obtained from the hydrophobic Au NPs dispersed into a series of hydrocarbons. The dispersion stability for Au NPs in hydrocarbons is monitored by UV-Vis spectroscopy, and the relative concentration of Au NPs is observed to still maintain over 80% after 3600 h.

  4. Metabolism of benzene, toluene, and xylene hydrocarbons in soil

    Science.gov (United States)

    Tsao; Song; Bartha

    1998-12-01

    Enrichment cultures obtained from soil exposed to benzene, toluene, and xylene (BTX) mineralized benzene and toluene but cometabolized only xylene isomers, forming polymeric residues. This observation prompted us to investigate the metabolism of 14C-labeled BTX hydrocarbons in soil, either individually or as mixtures. BTX-supplemented soil was incubated aerobically for up to 4 weeks in a sealed system that automatically replenished any O2 consumed. The decrease in solvent vapors and the production of 14CO2 were monitored. At the conclusion of each experiment, 14C distribution in solvent-extractable polymers, biomass, and humic material was determined, obtaining 14C mass balances of 85 to 98%. BTX compounds were extensively mineralized in soil, regardless of whether they were presented singly or in combinations. No evidence was obtained for the formation of solvent-extractable polymers from xylenes in soil, but 14C distribution in biomass (5 to 10%) and humus (12 to 32%) was unusual for all BTX compounds and especially for toluene and the xylenes. The results suggest that catechol intermediates of BTX degradation are preferentially polymerized into the soil humus and that the methyl substituents of the catechols derived from toluene and especially from xylenes enhance this incorporation. In contrast to inhibitory residues formed from xylene cometabolism in culture, the humus-incorporated xylene residues showed no significant toxicity in the Microtox assay.

  5. Metabolism of Benzene, Toluene, and Xylene Hydrocarbons in Soil†

    Science.gov (United States)

    Tsao, C.-W.; Song, H.-G.; Bartha, R.

    1998-01-01

    Enrichment cultures obtained from soil exposed to benzene, toluene, and xylene (BTX) mineralized benzene and toluene but cometabolized only xylene isomers, forming polymeric residues. This observation prompted us to investigate the metabolism of 14C-labeled BTX hydrocarbons in soil, either individually or as mixtures. BTX-supplemented soil was incubated aerobically for up to 4 weeks in a sealed system that automatically replenished any O2 consumed. The decrease in solvent vapors and the production of 14CO2 were monitored. At the conclusion of each experiment, 14C distribution in solvent-extractable polymers, biomass, and humic material was determined, obtaining 14C mass balances of 85 to 98%. BTX compounds were extensively mineralized in soil, regardless of whether they were presented singly or in combinations. No evidence was obtained for the formation of solvent-extractable polymers from xylenes in soil, but 14C distribution in biomass (5 to 10%) and humus (12 to 32%) was unusual for all BTX compounds and especially for toluene and the xylenes. The results suggest that catechol intermediates of BTX degradation are preferentially polymerized into the soil humus and that the methyl substituents of the catechols derived from toluene and especially from xylenes enhance this incorporation. In contrast to inhibitory residues formed from xylene cometabolism in culture, the humus-incorporated xylene residues showed no significant toxicity in the Microtox assay. PMID:9835584

  6. Reactive Extraction of Alcohols from Apolar Hydrocarbons with Aqueous Solutions

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The aqueous solutions are evaluated as sustainable reactive extraction solvents for the recovery of monohydroxyl alcohols (benzyl alcohol, 1-hexanol, cyclohexanol) present in few-percent concentrations in apolar hydrocarbons (toluene, n-hexane, and cyclohexane) by considering two approaches. An aqueous solution containing a reactive extractant, like borate salts, borate complexes, a monosalt of dicarboxylic acid,hydroxypropyl-cyclodextrins, and silver nitrate, shows limited potential to be used. Another approach, in which the alcohol is chemically modified prior to the extraction into an easy-extractable form, in this case a monoesterlcarboxylic acid, shows much more potential. An environmentally benign aqueous solution of sodium hydrogen carbonate can provide a distribution ratio of benzyl alcohol up to 200, leaving the solubility of the organic solvent in the aqueous solution unchanged relative to pure water and therefore increasing the selectivity with two orders of magnitude. The modification of aromatic, cyclo-aliphatic, and linear aliphatic alcohols can be performed efficiently in the apolar organic solvent without need for a catalyst. The recovery of the modified alcohol can be performed by back-extraction in combination with a spontaneous hydrolysis.

  7. Enrichment of light hydrocarbon mixture

    Science.gov (United States)

    Yang; Dali; Devlin, David; Barbero, Robert S.; Carrera, Martin E.; Colling, Craig W.

    2010-08-10

    Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.

  8. Reactions and Separations in Green Solvents

    NARCIS (Netherlands)

    Van Spronsen, J.

    2010-01-01

    Most chemical processes involve solvents in the reaction and the separation step. These solvents give rise to a heavy environmental and economical burden. Moreover, these solvents are based on non-sustainable resources like petroleum. The aim of this thesis has been to develop a number of alternativ

  9. Reactions and Separations in Green Solvents

    NARCIS (Netherlands)

    Van Spronsen, J.

    2010-01-01

    Most chemical processes involve solvents in the reaction and the separation step. These solvents give rise to a heavy environmental and economical burden. Moreover, these solvents are based on non-sustainable resources like petroleum. The aim of this thesis has been to develop a number of

  10. The solvent component of macromolecular crystals

    Energy Technology Data Exchange (ETDEWEB)

    Weichenberger, Christian X. [European Academy of Bozen/Bolzano (EURAC), Viale Druso 1, Bozen/Bolzano, I-39100 Südtirol/Alto Adige (Italy); Afonine, Pavel V. [Lawrence Berkeley National Laboratory (LBNL), 1 Cyclotron Road, Mail Stop 64R0121, Berkeley, CA 94720 (United States); Kantardjieff, Katherine [California State University, San Marcos, CA 92078 (United States); Rupp, Bernhard, E-mail: br@hofkristallamt.org [k.-k. Hofkristallamt, 991 Audrey Place, Vista, CA 92084 (United States); Medical University of Innsbruck, Schöpfstrasse 41, A-6020 Innsbruck (Austria)

    2015-04-30

    On average, the mother liquor or solvent and its constituents occupy about 50% of a macromolecular crystal. Ordered as well as disordered solvent components need to be accurately accounted for in modelling and refinement, often with considerable complexity. The mother liquor from which a biomolecular crystal is grown will contain water, buffer molecules, native ligands and cofactors, crystallization precipitants and additives, various metal ions, and often small-molecule ligands or inhibitors. On average, about half the volume of a biomolecular crystal consists of this mother liquor, whose components form the disordered bulk solvent. Its scattering contributions can be exploited in initial phasing and must be included in crystal structure refinement as a bulk-solvent model. Concomitantly, distinct electron density originating from ordered solvent components must be correctly identified and represented as part of the atomic crystal structure model. Herein, are reviewed (i) probabilistic bulk-solvent content estimates, (ii) the use of bulk-solvent density modification in phase improvement, (iii) bulk-solvent models and refinement of bulk-solvent contributions and (iv) modelling and validation of ordered solvent constituents. A brief summary is provided of current tools for bulk-solvent analysis and refinement, as well as of modelling, refinement and analysis of ordered solvent components, including small-molecule ligands.

  11. The hype with ionic liquids as solvents

    Science.gov (United States)

    Kunz, Werner; Häckl, Katharina

    2016-09-01

    In this mini review, we give our personal opinion about the present state of the art concerning Ionic Liquids, proposed as alternative solvents. In particular, we consider their different drawbacks and disadvantages and discuss the critical aspects of the research of Ionic Liquids as solvents. Finally, we point out some aspects on potentially promising Ionic Liquid solvents.

  12. STUDY OF SOLVENT AND CATALYST INTERACTIONS IN DIRECT COAL LIQUEFACTION

    Energy Technology Data Exchange (ETDEWEB)

    Michael T. Klein

    2000-01-01

    temperature for volatile evolution from coal was a reliable measure of coal rank. Because of this observation, a wide variety of coals of a wide range of ranks was investigated. It was shown in this work that measuring the peak temperature for volatile evolution was quite a precise indicator of rank and correlated closely wit the rank values obtained by measuring vitrinite reflectance, a more difficult measurement to make. This prompted the desire to know the composition of the volatile materials evolved as a function of coal rank. This was then measured by coupling a TGA to a mass spectrometer using laser activation and photoionization detection TG-PI-MS. The predominant species in volatiles of low rank coal turned out to be phenols with some alkenes. As the rank increases, the relative amount of alkenes and aromatic hydrocarbons increases and the oxygenated species decrease. It was shown that these volatiles were actually pyrolitic products and not volatilization products of coal. Solvent extraction experiments coupled with TG-PI-MS indicates that the low oiling and more extractable material are essentially similar in chemical types to the non-extractable portions but apparently higher molecular weight and therefor less extractable.

  13. High Pressure Preignition Chemistry of Hydrocarbons and Hydrocarbon Mixtures

    Science.gov (United States)

    2007-11-02

    and hydrocarbon blends in our various combustion systems, with emphasis on the effects of elevated pressure using our pressurized flow reactor ( PFR ...facility. Detailed experimental data were generated from the PFR for use in associated kinetic modeling work. We continued to develop and extend both

  14. Solvent cleaning system and method for removing contaminants from solvent used in resin recycling

    Science.gov (United States)

    Bohnert, George W.; Hand, Thomas E.; DeLaurentiis, Gary M.

    2009-01-06

    A two step solvent and carbon dioxide based system that produces essentially contaminant-free synthetic resin material and which further includes a solvent cleaning system for periodically removing the contaminants from the solvent so that the solvent can be reused and the contaminants can be collected and safely discarded in an environmentally safe manner.

  15. Total Petroleum Hydrocarbons (TPH): ToxFAQs

    Science.gov (United States)

    ... a state: This map displays locations where Total Petroleum Hydrocarbons (TPH) is known to be present. On ... I get more information? ToxFAQs TM for Total Petroleum Hydrocarbons (TPH) ( Hidrocarburos Totales de Petróleo (TPH) ) August ...

  16. Solvent refined coal studies: effects and characterization of treated solvent refined coal effluent. Progress report, FY 1977

    Energy Technology Data Exchange (ETDEWEB)

    Becker, C.D.; Woodfield, W.G.; Strand, J.A.

    1978-07-01

    The Freshwater Sciences Section of PNL has initiated biologically oriented studies at the P and M solvent refined coal (SRC) pilot plant on the Fort Lewis Reservation in western Washington. Essentially, the study objectives are to identify residual components in the treated SRC process and assess potential for adverse impact on water quality and aquatic biota. Since inception of research in mid-1976, six static toxicity tests with treated SRC process effluent have been conducted. Toxic components, not yet specifically identified, sometimes occur in the effluent. It is believed these components involve organic hydrocarbons of the phenol and cresol groups. Analyses have been obtained on inorganic and organic constituents in partially-treated and treated process effluent. Concentrations of inorganics identified in the effluent did not differ greatly from their concentrations in Lake Sequalitchew or SRC plant tap water, but the low concentrations may be due primarily to dilution with freshwater before discharge. Organics identified in the effluent are similar to those found in samples contaminated with petroleum, and involve many complex hydrocarbons.

  17. Pyrolysates of raw vitrinites and their residues after CS2-NMP solvent extraction and its significance for petroleum geology

    Institute of Scientific and Technical Information of China (English)

    LIU Dayong; PENG Ping'an

    2006-01-01

    Binary solvent (CS2-NMP) has extreme high extraction ability to coals, and it can extract most bitumens out of coals and vitrinites. And large amount of messages on side chains and their distribution character in vitrinites should be acquired through flash pyrolysis before and after binary solvent (CS2-NMP) extraction. A few low maturated coals have been selected and vitrinites are handpicked from coals. Then vitrinites have been extracted using different solvents in the order of polarity. Flash pyrolysis-Gas Chromatography/Mass spectrum has been applied to samples. The result shows that CS2-NMP is efficient for the extraction of vitirnites, giving much higher extraction yield than common solvents. Production ratio of liquid hydrocarbons in pyrolysates of vitrinites extracted with CS2-NMP is lower than that of raw vitrinites. And relative ratio of each component in pyrolysates has changed apparently. Production ratio of aliphatic hydrocarbons, especially those long chain aliphatics have decreased much after mixed solvent extraction. It shows that bitumens extracted with CS2-NMP have largely contributed to pyrolysates, especially those aliphatics in pyrolysates.

  18. 33 CFR 157.166 - Hydrocarbon emissions.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Hydrocarbon emissions. 157.166... Crude Oil Washing (COW) System on Tank Vessels Cow Operations § 157.166 Hydrocarbon emissions. If the... ballasted in that port the hydrocarbon vapors in each tank are contained by a means under § 157.132....

  19. Compositions and methods for hydrocarbon functionalization

    Energy Technology Data Exchange (ETDEWEB)

    Gunnoe, Thomas Brent; Fortman, George; Boaz, Nicholas C.; Groves, John T.

    2017-03-28

    Embodiments of the present disclosure provide for methods of hydrocarbon functionalization, methods and systems for converting a hydrocarbon into a compound including at least one group ((e.g., hydroxyl group) (e.g., methane to methanol)), functionalized hydrocarbons, and the like.

  20. Effect of solvents on the characteristics of rosin walled microcapsules prepared by a solvent evaporation technique.

    Science.gov (United States)

    Sheorey, D S; Dorle, A K

    1991-01-01

    Rosin microcapsules were prepared by a solvent evaporation technique using solvents with different rates of evaporation. Sulphadiazine was used as a model drug. The microcapsules were studied for their size, drug content, wall thickness, surface characteristics and in vitro release. The mean diameter increased and the drug content decreased as the rate of evaporation of the solvent increased. Fast evaporating solvents produced thick walled microcapsules with innumerable surface pores/cracks compared with slow evaporating solvents.

  1. Effective viscosity of confined hydrocarbons

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Samoilov, V.N.; Persson, B.N.J.

    2012-01-01

    We present molecular dynamics friction calculations for confined hydrocarbon films with molecular lengths from 20 to 1400 carbon atoms. We find that the logarithm of the effective viscosity ηeff for nanometer-thin films depends linearly on the logarithm of the shear rate: log ηeff=C-nlog γ̇, where...

  2. Fire-safe hydrocarbon fuels

    Energy Technology Data Exchange (ETDEWEB)

    Fodor, G.E.; Weatherford, W.D. Jr.; Wright, B.R.

    1979-11-06

    A stabilized, fire-safe, aqueous hydrocarbon fuel emulsion prepared by mixing: a diesel fuel; an emulsifier (consisting of oleyl diethanolamide, diethanolamine, and diethanolamine soap of oleic acid) which has been treated with about 0 to 7 1/2 of oleic acid. A modified version of this fuel also contains 0 to 0.5% of an antimisting agent, and water.

  3. Hydrophobic encapsulation of hydrocarbon gases.

    Science.gov (United States)

    Leontiev, Alexander V; Saleh, Anas W; Rudkevich, Dmitry M

    2007-04-26

    [reaction: see text] Encapsulation data for hydrophobic hydrocarbon gases within a water-soluble hemicarcerand in aqueous solution are reported. It is concluded that hydrophobic interactions serve as the primary driving force for the encapsulation, which can be used for the design of gas-separating polymers with intrinsic inner cavities.

  4. Photodegradation of mutagens in solvent-refined coal liquids

    Energy Technology Data Exchange (ETDEWEB)

    Kalkwarf, D.R.; Stewart, D.L.; Pelroy, R.A.; Weimer, W.C.

    1984-04-01

    The purpose of this investigation was to evaluate any changes in the chemical composition and microbial mutagenicities of two representative solvent-refined coal (SRC) liquids as a function of exposure time to sunlight and air. This information was desired to assess potential health hazards arising from ground spills of these liquids during production, transport and use. Results of microbial mutagenicity assays using Salmonella typhimurium TA98, conducted after exposure, showed that the mutagenicities of both an SRC-II fuel oil blend and an SRC-I process solvent decreased continuously with exposure time to air and that the decrease was accelerated by simultaneous exposure to simulated sunlight. The liquids were exposed as thin layers supported on surfaces of glass, paper, clay or aluminum; but the type of support had little effect on the results. The contrast between these results and the reported increases of mutagenesis in organisms exposed simultaneously to coal liquids and near-ultraviolet light suggested that short-lived mutagenic intermediates, e.g., organic free radicals, were formed in the liquids during exposure to light. The highest activities of microbial mutagenicity in the SRC liquids were found in fractions rich in amino polycyclic aromatic hydrocarbons (amino PAH). After a 36-hour exposure of the fuel oil blend to air in the dark, the mutagenicity of its amine-rich fraction was reduced by 65%; whereas a 36-hour exposure in the light reduced the mutagenicity of this fraction by 92%. Similar rates of reduction in mutagenicity were achieved in exposures of the process solvent. The mutagenicities of other chemical fractions remained low during exposure.

  5. The effect of solvents on the stabilities (color and Fe) of anthocyanin isolated from the red-color-melinjo peels

    Science.gov (United States)

    Tarmizi, Ermiziar; Lalasari, Latifa Hanum; Saragih, Raskita

    2015-12-01

    Anthocyanin from the red-color-melinjo peels could be isolated using a polar solvent (ethanol) [ermiziar, 2010]. The amount of hydrocarbons in the structure of anthocyanin might cause that anthocyanin could be isolated using a non polar solvent. The purpose of research is to isolate anthocyanin using non polar solvents (hexane and petroleum ether) with maceration steps for 24 hours and separate solvents using rotary evaporator equipment. The stability of anthocyanin could be observed every week (1,2,3 and 4 weeks) in various environmental conditions (with or without light in refrigerator and open or closed storage). The characterization of anthocyanin was analyzed with visual (physic photo) and or using equipments such as Fourier Transform Infrared Spectroscopy (FTIR) for determining functional groups, Ultraviolet-Visible Spectroscopy (UV/Vis) with 500-550 nm wavelengths for deciding absorption of anthocyanin and atomic absorption spectroscopy (AAS) for analyzing Fe element. The result showed that anthocyanin isolation with hexane solvent has yield higher than petroleum eter solvent. From the results of physic observation for 4 weeks looked that there are changing colors of samples significant after 3 and 4 weeks in cooler with or without light. The stability of anthocyanin color was the best on the storage time until 2 weeks using hexane solvent in refrigerator and closed condition that it has absorption of 0.6740 with 500 nm wavelengths and Fe concentration 6.29 ppm.

  6. The effect of solvents on the stabilities (color and Fe) of anthocyanin isolated from the red-color-melinjo peels

    Energy Technology Data Exchange (ETDEWEB)

    Tarmizi, Ermiziar, E-mail: uph-ermi@yahoo.com, E-mail: ermitarmizi@gmail.com; Saragih, Raskita, E-mail: raskitasaragih@yahoo.com [Indonesia Institute of Technology (ITI), Raya PuspiptekSerpong, Tangerang Banten 15320 (Indonesia); Lalasari, Latifa Hanum, E-mail: ifa-sari@yahoo.com, E-mail: lati003@lipi.go.id [Research Centre for Metallurgy and Material, Indonesian Institute of Sciences (LIPI), KawasanPuspiptekSerpong, Tangerang Selatan 15314 (Indonesia)

    2015-12-29

    Anthocyanin from the red-color-melinjo peels could be isolated using a polar solvent (ethanol) [ermiziar, 2010]. The amount of hydrocarbons in the structure of anthocyanin might cause that anthocyanin could be isolated using a non polar solvent. The purpose of research is to isolate anthocyanin using non polar solvents (hexane and petroleum ether) with maceration steps for 24 hours and separate solvents using rotary evaporator equipment. The stability of anthocyanin could be observed every week (1,2,3 and 4 weeks) in various environmental conditions (with or without light in refrigerator and open or closed storage). The characterization of anthocyanin was analyzed with visual (physic photo) and or using equipments such as Fourier Transform Infrared Spectroscopy (FTIR) for determining functional groups, Ultraviolet–Visible Spectroscopy (UV/Vis) with 500-550 nm wavelengths for deciding absorption of anthocyanin and atomic absorption spectroscopy (AAS) for analyzing Fe element. The result showed that anthocyanin isolation with hexane solvent has yield higher than petroleum eter solvent. From the results of physic observation for 4 weeks looked that there are changing colors of samples significant after 3 and 4 weeks in cooler with or without light. The stability of anthocyanin color was the best on the storage time until 2 weeks using hexane solvent in refrigerator and closed condition that it has absorption of 0.6740 with 500 nm wavelengths and Fe concentration 6.29 ppm.

  7. Advanced integrated solvent extraction systems

    Energy Technology Data Exchange (ETDEWEB)

    Horwitz, E.P.; Dietz, M.L.; Leonard, R.A. [Argonne National Lab., IL (United States)

    1997-10-01

    Advanced integrated solvent extraction systems are a series of novel solvent extraction (SX) processes that will remove and recover all of the major radioisotopes from acidic-dissolved sludge or other acidic high-level wastes. The major focus of this effort during the last 2 years has been the development of a combined cesium-strontium extraction/recovery process, the Combined CSEX-SREX Process. The Combined CSEX-SREX Process relies on a mixture of a strontium-selective macrocyclic polyether and a novel cesium-selective extractant based on dibenzo 18-crown-6. The process offers several potential advantages over possible alternatives in a chemical processing scheme for high-level waste treatment. First, if the process is applied as the first step in chemical pretreatment, the radiation level for all subsequent processing steps (e.g., transuranic extraction/recovery, or TRUEX) will be significantly reduced. Thus, less costly shielding would be required. The second advantage of the Combined CSEX-SREX Process is that the recovered Cs-Sr fraction is non-transuranic, and therefore will decay to low-level waste after only a few hundred years. Finally, combining individual processes into a single process will reduce the amount of equipment required to pretreat the waste and therefore reduce the size and cost of the waste processing facility. In an ongoing collaboration with Lockheed Martin Idaho Technology Company (LMITCO), the authors have successfully tested various segments of the Advanced Integrated Solvent Extraction Systems. Eichrom Industries, Inc. (Darien, IL) synthesizes and markets the Sr extractant and can supply the Cs extractant on a limited basis. Plans are under way to perform a test of the Combined CSEX-SREX Process with real waste at LMITCO in the near future.

  8. Influence of brine-hydrocarbon interactions on FT-IR microspectroscopic analyses of intracrystalline liquid inclusions

    Energy Technology Data Exchange (ETDEWEB)

    Pironon, J. (CNRS-CREGU, Vandoeuvre-les-Nancy (France)); Barres, O. (Univ. de Nancy 1, Vandoeuvre-les-Nancy (France))

    1992-01-01

    Hydrocarbon droplets surrounded by an aqueous phase and trapped in a host crystal (i.e., fluid inclusion) are windows to the migrating hydrocarbon-water emulsions in petroleum reservoirs. Using synthetic hydrocarbon inclusions, Fourier transform infrared microspectrometric analysis shows that the interactions at the two liquid (hydrocarbon-aqueous solution) phase interface can be determined on a 20 {mu}m scale. Spectral deformation, observed for the CH stretching bands, disappears when the alkali salt concentration decreases, when the organic solvent (CCl{sub 4} or C{sub 6}H{sub 6}) concentration increases, and when the {mu}FT-IR analysis point moves off the interface. This deformation is due to the cation effect on the interaction of the OH/CH dipoles. The Na{sup +}, K{sup +} cations break the water structure and induce modifications to the OH dipole at the interface, which then modifies the CH dipole moment and the CH stretching band intensity. Knowledge of the salinity of the aqueous phase is essential for complete understanding of infrared microanalysis of hydrocarbon fluid inclusions.

  9. Biodegradation of petroleum hydrocarbons in hypersaline environments

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Martins

    2012-09-01

    Full Text Available Literature on hydrocarbon degradation in extreme hypersaline media presents studies that point to a negative effect of salinity increase on hydrocarbonoclastic activity, while several others report an opposite tendency. Based on information available in the literature, we present a discussion on the reasons that justify these contrary results. Despite the fact that microbial ability to metabolize hydrocarbons is found in extreme hypersaline media, indeed some factors are critical for the occurrence of hydrocarbon degradation in such environments. How these factors affect hydrocarbon degradation and their implications for the assessment of hydrocarbon biodegradation in hypersaline environments are presented in this review.

  10. Syngas Upgrading to Hydrocarbon Fuels Technology Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Talmadge, M.; Biddy, M.; Dutta, A.; Jones, S.; Meyer, A.

    2013-03-01

    This technology pathway case investigates the upgrading of woody biomass derived synthesis gas (syngas) to hydrocarbon biofuels. While this specific discussion focuses on the conversion of syngas via a methanol intermediate to hydrocarbon blendstocks, there are a number of alternative conversion routes for production of hydrocarbons through a wide array of intermediates from syngas. Future work will also consider the variations to this pathway to determine the most economically viable and lowest risk conversion route. Technical barriers and key research needs have been identified that should be pursued for the syngas-to-hydrocarbon pathway to be competitive with petroleum-derived gasoline-, diesel- and jet-range hydrocarbon blendstocks.

  11. Biodegradation of petroleum hydrocarbons in hypersaline environments

    Science.gov (United States)

    Martins, Luiz Fernando; Peixoto, Raquel Silva

    2012-01-01

    Literature on hydrocarbon degradation in extreme hypersaline media presents studies that point to a negative effect of salinity increase on hydrocarbonoclastic activity, while several others report an opposite tendency. Based on information available in the literature, we present a discussion on the reasons that justify these contrary results. Despite the fact that microbial ability to metabolize hydrocarbons is found in extreme hypersaline media, indeed some factors are critical for the occurrence of hydrocarbon degradation in such environments. How these factors affect hydrocarbon degradation and their implications for the assessment of hydrocarbon biodegradation in hypersaline environments are presented in this review. PMID:24031900

  12. Dynamics around solutes and solute-solvent complexes in mixed solvents.

    Science.gov (United States)

    Kwak, Kyungwon; Park, Sungnam; Fayer, M D

    2007-09-04

    Ultrafast 2D-IR vibrational echo experiments, IR pump-probe experiments, and FT-IR spectroscopy of the hydroxyl stretch of phenol-OD in three solvents, CCl4, mesitylene (1, 3, 5 trimethylbenzene), and the mixed solvent of mesitylene and CCl4 (0.83 mole fraction CCl4), are used to study solute-solvent dynamics via observation of spectral diffusion. Phenol forms a complex with Mesitylene. In the mesitylene solution, there is only complexed phenol; in the CCl4 solution, there is only uncomplexed phenol; and in the mixed solvent, both phenol species are present. Dynamics of the free phenol in CCl4 or the mixed solvent are very similar, and dynamics of the complex in mesitylene and in the mixed solvent are very similar. However, there are differences in the slowest time scale dynamics between the pure solvents and the mixed solvents. The mixed solvent produces slower dynamics that are attributed to first solvent shell solvent composition variations. The composition variations require a longer time to randomize than is required in the pure solvents, where only density variations occur. The experimental results and recent MD simulations indicate that the solvent structure around the solute may be different from the mixed solvent's mole fraction.

  13. Aqueous reactions of chlorine dioxide with hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Rav-Acha, C.; Choshen, E.

    1987-11-01

    In contrast to mechanisms proposed earlier in the literature, according to which chlorine dioxide (ClO/sub 2/) reacts with various hydrocarbons in aqueous media by abstracting allylic or benzylic hydrogens, it is shown that ClO/sub 2/ reacts with olefins through initial electron transfer. Hydrocarbons that can undergo facile oxidation, such as polycyclic aromatic hydrocarbons (PAH) and some olefins, react with ClO/sub 2/ quite rapidly, while saturated aliphatic hydrocarbons, some aromatic hydrocarbons, and olefins substituted with electron-withdrawing groups remain unreactive. This was substantiated by comparing the reactivities toward ClO/sub 2/ of a variety of hydrocarbons, including aliphatic and aromatic hydrocarbons, saturated and unsaturated acids, PAH, or cyclic and acyclic olefins. The results were supported by a detailed kinetic and product study of the reaction between ClO/sub 2/ and some model compounds.

  14. Hydrocarbons emitted by waggle-dancing honey bees increase forager recruitment by stimulating dancing.

    Science.gov (United States)

    Gilley, David C

    2014-01-01

    Hydrocarbons emitted by waggle-dancing honey bees are known to reactivate experienced foragers to visit known food sources. This study investigates whether these hydrocarbons also increase waggle-dance recruitment by observing recruitment and dancing behavior when the dance compounds are introduced into the hive. If the hydrocarbons emitted by waggle-dancing bees affect the recruitment of foragers to a food source, then the number of recruits arriving at a food source should be greater after introduction of dance compounds versus a pure-solvent control. This prediction was supported by the results of experiments in which recruits were captured at a feeder following introduction of dance-compounds into a hive. This study also tested two nonexclusive behavioral mechanism(s) by which the compounds might stimulate recruitment; 1) increased recruitment could occur by means of increasing the recruitment effectiveness of each dance and/or 2) increased recruitment could occur by increasing the intensity of waggle-dancing. These hypotheses were tested by examining video records of the dancing and recruitment behavior of individually marked bees following dance-compound introduction. Comparisons of numbers of dance followers and numbers of recruits per dance and waggle run showed no significant differences between dance-compound and solvent-control introduction, thus providing no support for the first hypothesis. Comparison of the number of waggle-dance bouts and the number of waggle runs revealed significantly more dancing during morning dance-compound introduction than morning solvent-control introduction, supporting the second hypothesis. These results suggest that the waggle-dance hydrocarbons play an important role in honey bee foraging recruitment by stimulating foragers to perform waggle dances following periods of inactivity.

  15. IDENTIFICATION OF SOME CARCINOGENIC POLYCYCLIC AROMATIC HYDROCARBONS IN BANGLADESHI VEHICLES EXHAUST TAR BY GAS CHROMATOGRAPHY-MASS SPECTROPHOTOMETER

    Directory of Open Access Journals (Sweden)

    M. Amzad Hossain

    2010-06-01

    Full Text Available A more sensitive GC-MS method has been established for the determination of some carcinogenic polycyclic aromatic hydrocarbons (PAHs in vehicles exhaust tar samples. The tar samples were extracted using dichloromethane (DMC: n-hexane solvent mixture. A multi-layer clean-up (silica gel/sodium sulphate column was used, followed by glass fiber filter (GFF paper. The method was successfully applied to determine a number of PAHs present in exhaust tar sample of different vehicles of the Atomic Energy Centre, Dhaka, Bangladesh.   Keywords: Carcinogenic polycyclic aromatic hydrocarbons, vehicles tar samples, identification, GC-MS/MS

  16. Extracellular terpenoid hydrocarbon extraction and quantitation from the green microalgae Botryococcus braunii var. Showa.

    Science.gov (United States)

    Eroglu, Ela; Melis, Anastasios

    2010-04-01

    Mechanical fractionation and aqueous or aqueous/organic two-phase partition approaches were applied for extraction and separation of extracellular terpenoid hydrocarbons from Botryococcus braunii var. Showa. A direct spectrophotometric method was devised for the quantitation of botryococcene and associated carotenoid hydrocarbons extracted by this method. Separation of extracellular botryococcene hydrocarbons from the Botryococcus was achieved upon vortexing of the micro-colonies with glass beads, either in water followed by buoyant density equilibrium to separate hydrocarbons from biomass, or in the presence of heptane as a solvent, followed by aqueous/organic two-phase separation of the heptane-solubilized hydrocarbons (upper phase) from the biomass (lower aqueous phase). Spectral analysis of the upper heptane phase revealed the presence of two distinct compounds, one absorbing in the UV-C, attributed to botryococcene(s), the other in the blue region of the spectrum, attributed to a carotenoid. Specific extinction coefficients were developed for the absorbance of triterpenes at 190nm (epsilon = 90 +/- 5 mM(-1) cm(-1)) and carotenoids at 450 nm (epsilon=165+/-5mM(-1) cm(-1)) in heptane. This enabled application of a direct spectrophotometric method for the quantitation of water- or heptane-extractable botryococcenes and carotenoids. B. braunii var. Showa constitutively accumulates approximately 30% of the dry biomass as extractable (extracellular) botryococcenes, and approximately 0.2% of the dry biomass in the form of a carotenoid. It was further demonstrated that heat-treatment of the Botryococcus biomass substantially accelerates the rate and yield of the extraction process. Advances in this work serve as foundation for a cyclic Botryococcus growth, non-toxic extraction of extracellular hydrocarbons, and return of the hydrocarbon-depleted biomass to growth conditions for further product generation.

  17. Measurements of volatile hydrocarbons in ambient air coking plant `Walbrzych`

    Energy Technology Data Exchange (ETDEWEB)

    Michalski, R.; Weglarz, A.; Skrok, R. [Polish Academy of Sciences, Zabrze (Poland). Inst. of Environmental Engineering

    1998-12-31

    The air is a matrix very difficult to handle. In addition, the pollutants are usually present at very low concentrations. Many techniques can be used to collect air samples. The simplest way is to use special containers, but this procedure is expensive and time-consuming. The adsorption of pollutants on adsorbents shows a growing interest, despite the difficulty to choose the appropriate support in order to obtain quantitative yields. To overcome this problem, two or three types of adsorbents may be used in series for collecting a wide range of analytes. In addition, the miniaturization of these techniques (i.e. microtraps and solid-phase microextraction) is also very promising: easy to handle, low cost, no solvent required, detection limits at ppt level when sensitive detectors are used. If we have no money for this modern equipment we must use traditional methods for compounds determination. This paper describes measurements of volatile hydrocarbons (such as benzene, toluene, ethylbenzene, xylene and phenol) in ambient air of coking plant `Walbrzych` Measuring points were at streets: Beethoven 4, Dworcowa 2, Kosteckiego 5 and Zamkowa 1. BTEX were collected on graphitized carbon and phenol on Chromosorb 102. After that samples were extracted by solvents (dichloromethane for BTEX or benzene for phenol). Next step was the analysis by gas chromatography with flame ionization detector without preconcentration. The lower limit of detection was circa 0.01 {mu}g/m{sup 3} for each of the determined compounds. These measurements of hydrocarbons in town of Walbrzych were performed for two years from 1996 to 1998. 2 tabs.

  18. Selective Synthesis of Gasoline-Ranged Hydrocarbons from Syngas over Hybrid Catalyst Consisting of Metal-Loaded ZSM-5 Coupled with Copper-Zinc Oxide

    National Research Council Canada - National Science Library

    Ting Ma; Hiroyuki Imai; Manami Yamawaki; Kazusa Terasaka; Xiaohong Li

    2014-01-01

      The conversion of syngas (CO + H2) to gasoline-ranged hydrocarbons was carried out using a hybrid catalyst consisting of metal-loaded ZSM-5 coupled with Cu-ZnO in a near-critical n-hexane solvent...

  19. Microbial production of gaseous hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Hideo

    1987-10-20

    Microbial production of ethylene, isobutane and a saturated gaseous hydrocarbon mixture was described. Microbial ethylene production was studied with Penicillium digitatum IFO 9372 and a novel pathway of the ethylene biosynthesis through alpha-ketoglutarate was proposed. Rhodotorula minuta IFO 1102 was selected for the microbial production of isobutane and the interesting actions of L-leucine and L-phenylalanine for the isobutane production were found. It was finally presented about the microbial production of a saturated gaseous hydrocarbon mixture with Rhizopus japonicus IFO 4758 was described. A gas mixture was produced through a chemical reaction of SH compounds and some cellular component such as squalene under aerobic conditions. (4 figs, 7 tabs, 41 refs)

  20. Hydrocarbon Rocket Technology Impact Forecasting

    Science.gov (United States)

    Stuber, Eric; Prasadh, Nishant; Edwards, Stephen; Mavris, Dimitri N.

    2012-01-01

    Ever since the Apollo program ended, the development of launch propulsion systems in the US has fallen drastically, with only two new booster engine developments, the SSME and the RS-68, occurring in the past few decades.1 In recent years, however, there has been an increased interest in pursuing more effective launch propulsion technologies in the U.S., exemplified by the NASA Office of the Chief Technologist s inclusion of Launch Propulsion Systems as the first technological area in the Space Technology Roadmaps2. One area of particular interest to both government agencies and commercial entities has been the development of hydrocarbon engines; NASA and the Air Force Research Lab3 have expressed interest in the use of hydrocarbon fuels for their respective SLS Booster and Reusable Booster System concepts, and two major commercially-developed launch vehicles SpaceX s Falcon 9 and Orbital Sciences Antares feature engines that use RP-1 kerosene fuel. Compared to engines powered by liquid hydrogen, hydrocarbon-fueled engines have a greater propellant density (usually resulting in a lighter overall engine), produce greater propulsive force, possess easier fuel handling and loading, and for reusable vehicle concepts can provide a shorter turnaround time between launches. These benefits suggest that a hydrocarbon-fueled launch vehicle would allow for a cheap and frequent means of access to space.1 However, the time and money required for the development of a new engine still presents a major challenge. Long and costly design, development, testing and evaluation (DDT&E) programs underscore the importance of identifying critical technologies and prioritizing investment efforts. Trade studies must be performed on engine concepts examining the affordability, operability, and reliability of each concept, and quantifying the impacts of proposed technologies. These studies can be performed through use of the Technology Impact Forecasting (TIF) method. The Technology Impact

  1. Infrared absorption of 3-propenonyl (⋅CH{sub 2}CHCO) radical generated upon photolysis of acryloyl chloride [CH{sub 2}CHC(O)Cl] in solid para-H{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Das, Prasanta [Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, Hsinchu 30010, Taiwan (China); Lee, Yuan-Pern [Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, Hsinchu 30010, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan (China)

    2013-08-28

    Irradiation at 193 nm of a p-H{sub 2} matrix containing acryloyl chloride CH{sub 2}CHC(O)Cl at 3.2 K yielded infrared absorption lines at 3143.6 (ν{sub 1}), 3057.0 (ν{sub 2}), 3048.0 (ν{sub 3}), 2103.1 (ν{sub 4}), 1461.0 (ν{sub 5}), 1349.8 (ν{sub 6}), 1223.7 (ν{sub 11}+ν{sub 12} or 2ν{sub 12}), 1092.8 (ν{sub 8}), 918.1 (ν{sub 9}), 691.0 (ν{sub 10}), 624.3 (ν{sub 11}), and 597.1 (ν{sub 12}) cm{sup −1} that are assigned to the 3-propenonyl (⋅CH{sub 2}CHCO) radical. The assignments are based on the photolytic behavior and a comparison of observed vibrational wavenumbers and infrared intensities with those predicted with the B3PW91/aug-cc-pVDZ method. The observation is consistent with a major radical formation channel CH{sub 2}CHCO + Cl followed by escape of the Cl atom from the original p-H{sub 2} cage. The observation of 3-propenonyl (⋅CH{sub 2}CHCO) radical but not 3-propenalyl (s-cis- or s-trans-CH{sub 2}CHĊO) radical indicates that the former is the most stable isomer and that the barrier heights for conversion from s-cis- or s-trans-CH{sub 2}CHĊO to ⋅CH{sub 2}CHCO are small.

  2. Comparative Genomics of the Ubiquitous, Hydrocarbon-degrading Genus Marinobacter

    Science.gov (United States)

    Singer, E.; Webb, E.; Edwards, K. J.

    2012-12-01

    using fimbriae and pili. Formation of biofilm with biosurfactant characteristics has been observed in Marinobacter cultures and environmental strains in relation to hydrocarbon degradation. Genomic potential exists for the synthesis of biofilm-related carbon and energy storage compounds, e.g. alginate and isoprenoid wax esters, and quorum sensing encoded by the regulatory luxR gene and N-acyl-L-homoserine lactone (AHL) signals. Halotolerance is predicted to be achieved through biosynthesis and/or import of compatible solutes, including glycine betaine, choline, ectoine, sucrose, periplasmic glucans as well as membrane channel activity regulating intracellular sodium, potassium and chloride concentration balance. Gene abundances concur with those observed in sequenced halophilic Halomonas genomes. Defense mechanisms are plentiful and include arsenate, organic solvent, copper, and mercuric resistance, compounds, which frequently occur in oil refinery wastewater. The Marinobacter genomes reflect dynamic environments and diverse interactions with viruses and other bacteria with similar metabolic strategies, as reflected by the large number of integrases and transposases. This study has provided comprehensive genomic insights into the metabolic versatility and predicted environmental impact potential of one of the most ubiquitous bacterial genera.

  3. Deep desulfurization of hydrocarbon fuels

    Science.gov (United States)

    Song, Chunshan [State College, PA; Ma, Xiaoliang [State College, PA; Sprague, Michael J [Calgary, CA; Subramani, Velu [State College, PA

    2012-04-17

    The invention relates to processes for reducing the sulfur content in hydrocarbon fuels such as gasoline, diesel fuel and jet fuel. The invention provides a method and materials for producing ultra low sulfur content transportation fuels for motor vehicles as well as for applications such as fuel cells. The materials and method of the invention may be used at ambient or elevated temperatures and at ambient or elevated pressures without the need for hydrogen.

  4. Hydrocarbon prospectivity in Western Greece

    Energy Technology Data Exchange (ETDEWEB)

    Maravelis, Angelos; Makrodimitras, George; Zelilidis, Avraam [Patras Univ. (Greece). Lab. of Sedimentology

    2012-06-15

    The geology of Western Greece is dominated by the most external zones of the Hellenide fold-and-thrust belt, namely the Pre-Apulian (or Paxoi) and Ionian zones. With Western Greece and Albania having undergone, in broad terms, similar geological histories, also the hydrocarbon potentials of both areas may be compared. Likewise, the hydrocarbon potential of Italy's Apulian Platform, adjoining in the westerly offshore, may serve as an analogue. Three basin types within Western Greece that deserve hydrocarbon exploration have been examined and are grouped, correlated to major tectonic features, namely foreland (Ionian thrusts' foreland basin), piggy-back (Ionian thrusts' back-arc basin) and strike-slip basins. Additionally, strike-slip basins are further subdivided into the basin north of the Borsh-Khardhiqit strike-slip fault and the Preveza basin, north of Cephalonia transfer fault. Their filling histories suggest the occurrence of Mesozoic carbonate plays and Oligocene/Miocene sandstone plays both for oil and gas.

  5. Abnormal pressure in hydrocarbon environments

    Science.gov (United States)

    Law, B.E.; Spencer, C.W.

    1998-01-01

    Abnormal pressures, pressures above or below hydrostatic pressures, occur on all continents in a wide range of geological conditions. According to a survey of published literature on abnormal pressures, compaction disequilibrium and hydrocarbon generation are the two most commonly cited causes of abnormally high pressure in petroleum provinces. In young (Tertiary) deltaic sequences, compaction disequilibrium is the dominant cause of abnormal pressure. In older (pre-Tertiary) lithified rocks, hydrocarbon generation, aquathermal expansion, and tectonics are most often cited as the causes of abnormal pressure. The association of abnormal pressures with hydrocarbon accumulations is statistically significant. Within abnormally pressured reservoirs, empirical evidence indicates that the bulk of economically recoverable oil and gas occurs in reservoirs with pressure gradients less than 0.75 psi/ft (17.4 kPa/m) and there is very little production potential from reservoirs that exceed 0.85 psi/ft (19.6 kPa/m). Abnormally pressured rocks are also commonly associated with unconventional gas accumulations where the pressuring phase is gas of either a thermal or microbial origin. In underpressured, thermally mature rocks, the affected reservoirs have most often experienced a significant cooling history and probably evolved from an originally overpressured system.

  6. Molecular Thermodynamic Modeling of Mixed Solvent Solubility

    DEFF Research Database (Denmark)

    Ellegaard, Martin Dela; Abildskov, Jens; O’Connell, John P.

    2010-01-01

    A method based on statistical mechanical fluctuation solution theory for composition derivatives of activity coefficients is employed for estimating dilute solubilities of 11 solid pharmaceutical solutes in nearly 70 mixed aqueous and nonaqueous solvent systems. The solvent mixtures range from...... nearly ideal to strongly nonideal. The database covers a temperature range from 293 to 323 K. Comparisons with available data and other existing solubility methods show that the method successfully describes a variety of observed mixed solvent solubility behaviors using solute−solvent parameters from...

  7. A solvent tolerant isolate of Enterobacter aerogenes.

    Science.gov (United States)

    Gupta, Anshu; Singh, Rajni; Khare, S K; Gupta, M N

    2006-01-01

    A solvent tolerant strain of Enterobacter aerogenes was isolated from soil by cyclohexane enrichment. Presence of cyclohexane (20%) in culture media prolonged the lag phase and caused reduction in biomass. Transmission electron micrographs showed convoluted cell membrane and accumulation of solvent in case of the cells grown in cyclohexane. The Enterobacter isolate was able to grow in the range of organic solvents having log P above 3.2 and also in presence of mercury, thus showing potential for treatment of solvent rich wastes.

  8. Organic solvent use in enterprises in Japan.

    Science.gov (United States)

    Nagasawa, Yasuhiro; Ukai, Hirohiko; Okamoto, Satoru; Samoto, Hajime; Itoh, Kenji; Moriguchi, Jiro; Sakuragi, Sonoko; Ohashi, Fumiko; Takada, Shiro; Kawakami, Tetsuya; Ikeda, Masayuki

    2011-01-01

    This study was initiated to elucidate possible changes in types of organic solvents (to be called solvents in short) used in enterprises in Japan through comparison of current solvent types with historical data since 1983. To investigate current situation in solvent use in enterprises, surveys were conducted during one year of 2009 to 2010. In total, workroom air samples in 1,497 unit workplaces with solvent use were analyzed in accordance with regulatory requirements. Typical use pattern of solvents was as mixtures, accounting for >70% of cases. Adhesives spreading (followed by adhesion) was relatively common in small-scale enterprises, whereas printing and painting work was more common in middle-scale ones, and solvent use for testing and research purpose was basically in large-scaled enterprises. Through-out printing, painting, surface coating and adhesive application, toluene was most common (being detected in 49 to 82% of workplaces depending on work types), whereas isopropyl alcohol was most common (49%) in degreasing, cleaning and wiping workplaces. Other commonly used solvents were methyl alcohol, ethyl acetate and acetone (33 to 37%). Comparison with historical data in Japan and literature-retrieved data outside of Japan all agreed with the observation that toluene is the most commonly used solvent. Application of trichloroethylene and 1,1,1-trichloroethane, once common in 1980s, has ceased to exist in recent years.

  9. Extractive Distillation with Salt in Solvent

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Extractive distillation with salt in solvent is a new process for producing anhydrous ethanol by combining the principle of "salt effect" and some traditional extractive distillation methods. Compared with the common extractive distillation the performance of solvent is improved, the recycling amount of solvent is reduced to 1/4-1/5, and the number of theoretical plates is reduced to 1/3. Energy consumption and cost of equipment are also reduced and continuous production is realized. High efficiency and low solvent wastage make this technique feasible.

  10. OCCUPATIONAL SOLVENT EXPOSURE ASSOCIATED WITH DEVELOPMENTAL TOXICITY

    Directory of Open Access Journals (Sweden)

    Alina-Costina LUCA

    2016-05-01

    Full Text Available Organic solvent is a broad term that applies to many classes of chemicals. The solvent (benzene, toluene etc. aspects of occupational exposure are reviewed via the examination of the use, occurrence, and disposition as well as population’s potential of risk. The general public can be exposed to solvent in ambient air as a result of its occurrence in paint process. Solvents are primarily irritants to the skin and mucous membranes and have narcotic properties at high concentrations. Published epidemiological data identified various types of birth defects in certain occupations.

  11. Desiccation tolerance in Anopheles coluzzii: the effects of spiracle size and cuticular hydrocarbons.

    Science.gov (United States)

    Arcaz, Arthur C; Huestis, Diana L; Dao, Adama; Yaro, Alpha S; Diallo, Moussa; Andersen, John; Blomquist, Gary J; Lehmann, Tovi

    2016-06-01

    The African malaria mosquitoes Anopheles gambiae and Anopheles coluzzii range over forests and arid areas, where they withstand dry spells and months-long dry seasons, suggesting variation in their desiccation tolerance. We subjected a laboratory colony (G3) and wild Sahelian mosquitoes during the rainy and dry seasons to desiccation assays. The thoracic spiracles and amount and composition of cuticular hydrocarbons (CHCs) of individual mosquitoes were measured to determine the effects of these traits on desiccation tolerance. The relative humidity of the assay, body water available, rate of water loss and water content at death accounted for 88% of the variation in desiccation tolerance. Spiracle size did not affect the rate of water loss or desiccation tolerance of the colony mosquitoes, as was the case for the total CHCs. However, six CHCs accounted for 71% of the variation in desiccation tolerance and three accounted for 72% of the variation in the rate of water loss. Wild A. coluzzii exhibited elevated desiccation tolerance during the dry season. During that time, relative thorax and spiracle sizes were smaller than during the rainy season. A smaller spiracle size appeared to increase A. coluzzii's desiccation tolerance, but was not statistically significant. Seasonal changes in CHC composition were detected in Sahelian A. coluzzii Stepwise regression models suggested the effect of particular CHCs on desiccation tolerance. In conclusion, the combination of particular CHCs along with the total amount of CHCs is a primary mechanism conferring desiccation tolerance in A. coluzzii, while variation in spiracle size might be a secondary mechanism. © 2016. Published by The Company of Biologists Ltd.

  12. Hydrocarbon Reserves: Abundance or Scarcity

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    IFP and the OAPEC jointly organize a regular international seminar dealing with world oil-related problems appearing in the news. For the first time, this seminar has been opened to oil and gas company specialists, service companies, research centers and independents. This year's theme concerns oil and gas reserves: are they abundant or are we headed towards the shortages announced by some experts? This theme is especially topical in that: oil and gas currently meet two thirds of world energy needs and almost completely dominate the transport sector; the reserves declared by the OAPEC countries account for nearly half of world reserves; the price of a barrel of oil went through the roof in 2004; world energy demand is growing fast and alternative sources of energy are far from ready to take over from oil and gas in the next few decades. Since the reserves correspond to the volume it is technically and economically viable to produce, the seminar has, of course, dealt with the technical and economic questions that arise in connection with exploration and production, but it has also considered changes in the geopolitical context. Presentations by the leading companies of the OAPEC countries and by the IFP group were completed by presentation from the International Energy Agency (IEA), the United States Geological Survey (USGS), the IHS Energy Group, Total and Gaz de France. This document gathers the transparencies of the following presentations: Hydrocarbon reserves in OAPEC members countries: current and future (M. Al-Lababidi); Non OAPEC liquid reserves and production forecasts (Y. Mathieu); World oil and gas resources and production outlook (K. Chew); Global investments in the upstream (F. Birol); Total's policy in the oil and gas sector (C. de Margerie); Gaz de France's policy in the oil and gas sector (J. Abiteboul); NOC/IOC's opportunities in OPEC countries (I. Sandrea); Relationships between companies, countries and investors: How they may

  13. [Identification of organic solvents in the water of a freshly coated drinking-water reservoir].

    Science.gov (United States)

    Karrenbrock, F; Haberer, K

    1982-01-01

    Chloro-caoutschouc coatings on reservoirs made of concrete can release organic solvents to the drinking water for several month after applying. These solvents can be identified directly in the water by highly sensitive analytical methods (GC/MS). The concentrations verified distinctly exceed the maximum permissible concentration of 10 micrograms/l as suggested by the EEG for the parameter: "dissolved or emulsified hydrocarbons (after extraction by petroleum ether); mineral oils" (2). Protective chloro-caoutchouc coatings should therefore be tested for the release of organic substances to water according to the KTW-Recommendations of the German Federal Health Bureau (1). In future drinking water reservoirs should not be coated unless compelling reasons exist, such as to protect concrete against aggressive water.

  14. Mild extractability and bioavailability of polycyclic aromatic hydrocarbons in soil

    Energy Technology Data Exchange (ETDEWEB)

    Tang, J.; Alexander, M.

    1999-12-01

    A study was conducted to determine the relationship between bioavailability of unaged and aged polycyclic aromatic hydrocarbons (PAHs) in soil and the amounts detected by mild solvent extraction. More aged than unaged anthracene remained in Lima loam following introduction of earthworms (Eisenia foetida), a mixed culture containing anthracene-degrading microorganisms, or earthworms or wheat after bacterial biodegradation of the compound. Aging decreased the percentage of anthracene recovered by mild extraction with n-butanol from soil following introduction of earthworms, growth of wheat, biodegradation by bacteria, or when maintained sterile. Biodegradation resulted in a marked decrease in the percentage of aged and unaged anthracene recovered from soil by mild extraction with n-butanol or ethyl acetate. Aging of fluoranthene and pyrene decreased the amount removed by mild extraction with n-butanol, ethyl acetate, and propanol. The uptake of aged and unaged anthracene, fluoranthene, and pyrene by earthworms was correlated with the amounts recovered from soil by mild extraction with n-butanol, propanol, and ethyl acetate. The retention of aged and unaged anthracene by wheat and barley was correlated with the amounts recovered from soil by the same procedure. The authors suggest that mild extraction with organic solvents can be used to predict the bioavailability of PAHs in soil.

  15. Additive diffusion from LDPE slabs into contacting solvents as a function of solvent absorption

    NARCIS (Netherlands)

    Helmroth, I.E.; Dekker, M.; Hankemeier, Th.

    2003-01-01

    This article describes the simultaneous diffusion of a migrant and a solvent in low density polyethylene (LDPE). The migrant (Irganox 1076) moves out of the slab, while the solvent (isooctane, n-heptane or cyclohexane) moves inwards. Solvent absorption was measured separately by following the increa

  16. Additive Diffusion from LDPE Slabs into Contacting Solvents as a Function of Solvent Absorption

    NARCIS (Netherlands)

    Helmroth, I.E.; Dekker, M.; Hankemeier, T.

    2003-01-01

    This article describes the simultaneous diffusion of a migrant and a solvent in low density polyethylene (LDPE). The migrant (Irganox 1076) moves out of the slab, while the solvent (isooctane, n-heptane or cyclohexane) moves inwards. Solvent absorption was measured separately by following the increa

  17. Kinetic solvent effects on hydrogen abstraction reactions from carbon by the cumyloxyl radical. The importance of solvent hydrogen-bond interactions with the substrate and the abstracting radical.

    Science.gov (United States)

    Salamone, Michela; Giammarioli, Ilaria; Bietti, Massimo

    2011-06-03

    A kinetic study of the hydrogen atom abstraction reactions from propanal (PA) and 2,2-dimethylpropanal (DMPA) by the cumyloxyl radical (CumO•) has been carried out in different solvents (benzene, PhCl, MeCN, t-BuOH, MeOH, and TFE). The corresponding reactions of the benzyloxyl radical (BnO•) have been studied in MeCN. The reaction of CumO• with 1,4-cyclohexadiene (CHD) also has been investigated in TFE solution. With CHD a 3-fold increase in rate constant (k(H)) has been observed on going from benzene, PhCl, and MeCN to TFE. This represents the first observation of a sizable kinetic solvent effect for hydrogen atom abstraction reactions from hydrocarbons by alkoxyl radicals and indicates that strong HBD solvents influence the hydrogen abstraction reactivity of CumO•. With PA and DMPA a significant decrease in k(H) has been observed on going from benzene and PhCl to MeOH and TFE, indicative of hydrogen-bond interactions between the carbonyl lone pair and the solvent in the transition state. The similar k(H) values observed for the reactions of the aldehydes in MeOH and TFE point toward differential hydrogen bond interactions of the latter solvent with the substrate and the radical in the transition state. The small reactivity ratios observed for the reactions of CumO• and BnO• with PA and DMPA (k(H)(BnO•)/k(H)(CumO•) = 1.2 and 1.6, respectively) indicate that with these substrates alkoxyl radical sterics play a minor role.

  18. Correlation between hydrocarbon distribution and water-hydrocarbon ratio in Fischer-Tropsch synthesis

    Institute of Scientific and Technical Information of China (English)

    Xiaofeng Zhou; Qingling Chen; Yuewu Tao; Huixin Weng

    2011-01-01

    In order to shorten the evaluation cycle of cobalt catalyst before the optimized catalyst is fixed on,a mathematical method is proposed to calculate weight percentage of C5+ hydrocarbons.Based on the carbide polymerization mechanism and the main hydrocarbons being linear alkanes and α-olefins,the correlation between hydrocarbon distribution and the molecular mass ratio of water to hydrocarbons is discussed.The result shows the ratio was within the range of 1.125-1.286 and the lower the ratio,the more gaseous hydrocarbons were obtained.Moreover,a linear equation between the weight percentage of C5+ hydrocarbons and the weight ratio of C5+ hydrocarbons to the total water is established.These results are validated by corresponding experiments.The weight percentage of C5+ hydrocarbons could be immediately calculated by this linear equation without detailed gas chromatography (GC) analysis of them.

  19. A combination of solvent extraction and freeze thaw for oil recovery from petroleum refinery wastewater treatment pond sludge.

    Science.gov (United States)

    Hu, Guangji; Li, Jianbing; Hou, Haobo

    2015-01-01

    A combination of solvent extraction and freeze thaw was examined for recovering oil from the high-moisture petroleum refinery wastewater treatment pond sludge. Five solvents including cyclohexane (CHX), dichloromethane (DCM), methyl ethyl ketone (MEK), ethyl acetate (EA), and 2-propanol (2-Pro) were examined. It was found that these solvents except 2-Pro showed a promising oil recovery rate of about 40%, but the recycling of DCM solvent after oil extraction was quite low. Three solvents (CHX, MEK and EA) were then selected for examining the effect of freeze/thaw treatment on improving the quality of recovered oil. This treatment increased the total petroleum hydrocarbon (TPH) content in recovered oil from about 40% to 60% for both MEK and EA extractions, but little effect was observed for CHX extraction. Although the solid residue after oil recovery had a significantly decreased TPH content, a high concentration of heavy metals was observed, indicating that this residue may require proper management. In general, the combination of solvent extraction with freeze/thaw is effective for high-moisture oily hazardous waste treatment.

  20. HYDROCARBON AND SULFUR SENSORS FOR SOFC SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    A.M. Azad; Chris Holt; Todd Lesousky; Scott Swartz

    2003-11-01

    The following report summarizes work conducted during the Phase I program Hydrocarbon and Sulfur Sensors for SOFC Systems under contract No. DE-FC26-02NT41576. For the SOFC application, sensors are required to monitor hydrocarbons and sulfur in order to increase the operation life of SOFC components. This report discusses the development of two such sensors, one based on thick film approach for sulfur monitoring and the second galvanic based for hydrocarbon monitoring.

  1. 40 CFR 90.316 - Hydrocarbon analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Hydrocarbon analyzer calibration. 90... Equipment Provisions § 90.316 Hydrocarbon analyzer calibration. (a) Calibrate the FID and HFID hydrocarbon... thereafter, adjust the FID and HFID hydrocarbon analyzer for optimum hydrocarbon response as specified...

  2. 40 CFR 86.121-90 - Hydrocarbon analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Hydrocarbon analyzer calibration. 86... Complete Heavy-Duty Vehicles; Test Procedures § 86.121-90 Hydrocarbon analyzer calibration. The hydrocarbon... FID and HFID hydrocarbon analyzers shall be adjusted for optimum hydrocarbon response....

  3. 40 CFR 91.316 - Hydrocarbon analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Hydrocarbon analyzer calibration. 91....316 Hydrocarbon analyzer calibration. (a) Calibrate the FID and HFID hydrocarbon analyzer as described... thereafter, adjust the FID and HFID hydrocarbon analyzer for optimum hydrocarbon response as specified...

  4. 40 CFR 89.319 - Hydrocarbon analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Hydrocarbon analyzer calibration. 89... Equipment Provisions § 89.319 Hydrocarbon analyzer calibration. (a) The FID hydrocarbon analyzer shall... and at least annually thereafter, adjust the FID hydrocarbon analyzer for optimum hydrocarbon...

  5. Solvent effect in the Walden inversion reactions

    Science.gov (United States)

    Jaume, J.; Lluch, J. M.; Oliva, A.; Bertrán, J.

    1984-04-01

    The solvent effect on the fluoride exchange reaction has been studied by means of ab initio calculations using the 3-21G basis set. It is shown that the motion of the solvent molecules is an important part of the reaction coordinate.

  6. Solvation of rhodamine575 in some solvents

    Science.gov (United States)

    Sharma, Amit

    2016-05-01

    FTIR spectra of Rhodamine575 dye in powder form and in different solvents are reported. Positions of some of the observed FTIR bands show noticeable change in solvents. The bands, which shift, have contributions from the vibrational motion of nitrogen atoms of the ethylamine groups, oxygen atom of the carboxylic group attached to the phenyl ring and oxygen atom of the Xanthene ring.

  7. Composite capillary membrane for solvent resistant nanofiltration

    NARCIS (Netherlands)

    Dutczak, S.M.; Luiten-Olieman, Maria W.J.; Zwijnenberg, Harmen Jan; Bolhuis-Versteeg, Lydia A.M.; Winnubst, Aloysius J.A.; Hempenius, Mark A.; Benes, Nieck Edwin; Wessling, Matthias; Stamatialis, Dimitrios

    2011-01-01

    Solvent resistant nanofiltration (SRNF) is a membrane separation process allowing for an efficient separation of small molecules of 200–1000 g mol−1 from organic solvents. The application of SRNF in industry applications is currently hindered by a limited choice of SRNF membranes and configurations.

  8. Supercritical-Multiple-Solvent Extraction From Coal

    Science.gov (United States)

    Corcoran, W.; Fong, W.; Pichaichanarong, P.; Chan, P.; Lawson, D.

    1983-01-01

    Large and small molecules dissolve different constituents. Experimental apparatus used to test supercritical extraction of hydrogen rich compounds from coal in various organic solvents. In decreasing order of importance, relevant process parameters were found to be temperature, solvent type, pressure, and residence time.

  9. Improved Supercritical-Solvent Extraction of Coal

    Science.gov (United States)

    Compton, L.

    1982-01-01

    Raw coal upgraded by supercritical-solvent extraction system that uses two materials instead of one. System achieved extraction yields of 20 to 49 weight percent. Single-solvent yields are about 25 weight percent. Experimental results show extraction yields may be timedependent. Observed decreases in weight of coal agreed well with increases in ash content of residue.

  10. Solvent-vapor-assisted imprint lithography

    NARCIS (Netherlands)

    Voicu, Nicoleta E.; Ludwigs, Sabine; Crossland, Edward J. W.; Andrew, Piers; Steiner, Ullrich

    2007-01-01

    Sub-micrometer features are replicated into high-molecular-weight polymer resists by using solvent-assisted nanoimprint lithography (see figure). By swelling the polymer in a controlled solvent-vapor atmosphere, millibar pressures and ambient temperatures are sufficient to achieve high-fidelity

  11. Relationship between Fermi Resonance and Solvent Effects

    Institute of Scientific and Technical Information of China (English)

    JIANG Xiu-Lan; LI Dong-Fei; SUN Cheng-Lin; LI Zhan-Long; YANG Guang; ZHOU Mi; LI Zuo-Wei; GAO Shu-Qin

    2011-01-01

    We theoretically and experimentally study the relationship between Fermi resonance and solvent effects and investigate the Fermi resonance of p-benzoquinone and cyclopentanone in different solvents and the Fermi resonance of CS2 in C6H6 at different concentrations. Also, we investigate the Fermi resonance of C6H6 and CCl4 in their solution at different pressures. It is found that solvent effects can be utilized to search Fermi resonance parameters such as coupling coefficient and spectral intensity ratio, etc., on the other hand, the mechanism of solvent effects can be revealed according to Fermi resonance at high pressure.%@@ We theoretically and experimentally study the relationship between Fermi resonance and solvent effects and investigate the Fermi resonance of p-benzoquinone and cyclopentanone in different solvents and the Fermi resonance of CS2 in C6H6 at different concentrations.Also,we investigate the Fermi resonance of C6H6 and CCl4 in their solution at different pressures.It is found that solvent effects can be utilized to search Fermi resonance parameters such as coupling coefficient and spectral intensity ratio,etc.,on the other hand,the mechanism of solvent effects can be revealed according to Fermi resonance at high pressure.

  12. Selection of Environmentally Friendly Solvents for the Extravehicular Mobility Unit Secondary Oxygen Pack Cold Trap Testing

    Science.gov (United States)

    Steele, John; Chullen, Cinda; Morenz, Jesse; Stephenson, Curtis

    2010-01-01

    Freon-113(TradeMark) has been used as a chemistry lab sampling solvent at NASA/JSC for EMU (extravehicular Mobility Unit) SOP (Secondary Oxygen Pack) oxygen testing Cold Traps utilized at the USA (United Space Alliance) Houston facility. Similar testing has occurred at the HSWL (Hamilton Sundstrand Windsor Locks) facility. A NASA Executive Order bans the procurement of all ODS (ozone depleting substances), including Freon-113 by the end of 2009. In order to comply with NASA direction, HSWL began evaluating viable solvents to replace Freon-113 . The study and testing effort to find Freon-113 replacements used for Cold Trap sampling is the subject of this paper. Test results have shown HFE-7100 (a 3M fluorinated ether) to be an adequate replacement for Freon-113 as a solvent to remove and measure the non-volatile residue collected in a Cold Trap during oxygen testing. Furthermore, S-316 (a Horiba Instruments Inc. high molecular weight, non-ODS chlorofluorocarbon) was found to be an adequate replacement for Freon-113 as a solvent to reconstitute non-volatile residue removed from a Cold Trap during oxygen testing for subsequent HC (hydrocarbon) analysis via FTIR (Fourier Transform Infrared Spectroscopy).

  13. Lignin Peroxidase Oxidation of Aromatic Compounds in Systems Containing Organic Solvents

    Science.gov (United States)

    Vazquez-Duhalt, Rafael; Westlake, Donald W. S.; Fedorak, Phillip M.

    1994-01-01

    Lignin peroxidase from Phanerochaete chrysosporium was used to study the oxidation of aromatic compounds, including polycyclic aromatic hydrocarbons and heterocyclic compounds, that are models of moieties of asphaltene molecules. The oxidations were done in systems containing water-miscible organic solvents, including methanol, isopropanol, N, N-dimethylformamide, acetonitrile, and tetrahydrofuran. Of the 20 aromatic compounds tested, 9 were oxidized by lignin peroxidase in the presence of hydrogen peroxide. These included anthracene, 1-, 2-, and 9-methylanthracenes, acenaphthene, fluoranthene, pyrene, carbazole, and dibenzothiophene. Of the compounds studied, lignin peroxidase was able to oxidize those with ionization potentials of <8 eV (measured by electron impact). The reaction products contain hydroxyl and keto groups. In one case, carbon-carbon bond cleavage, yielding anthraquinone from 9-methylanthracene, was detected. Kinetic constants and stability characteristics of lignin peroxidase were determined by using pyrene as the substrate in systems containing different amounts of organic solvent. Benzyl alkylation of lignin peroxidase improved its activity in a system containing water-miscible organic solvent but did not increase its resistance to inactivation at high solvent concentrations. PMID:16349176

  14. Detection of hydrocarbons in irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    Miyahara, Makoto; Maitani, Tamio [National Inst. of Health Sciences, Tokyo (Japan); Saito, Akiko; Kamimura, Tomomi; Nagasawa, Taeko [Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Allied Health Sciences; Kobayashi, Yasuo; Ito, Hitoshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Establishment

    2003-06-01

    The hydrocarbon method for the detection of irradiated foods is now recognized as the international technique. This method is based on radiolysis of fatty acids in food to give hydrocarbons. In order to expand this technique's application, ten foods (butter, cheese, chicken, pork, beef, tuna, dry shrimp, avocado, papaya, and mango) were irradiated in the range from 0.5 to 10 kGy and the hydrocarbons in them were detected. Recoveries of the hydrocarbons from most foods were acceptable (38-128%). Some hydrocarbons were found in non-irradiated foods, particularly, in butter, cheese, tuna, and shrimp. Seven irradiated foods, butter, cheese, chicken, beef, pork, tuna, dry shrimp, and avocado were detectable at their practical doses by measuring the appropriate marker hydrocarbons. In most case, marker hydrocarbon will be 1,7-hexadecadiene. However, the marker hydrocarbons produced only in irradiated foods varied from food to food; therefore, it is necessary to check a specific irradiated food for marker hydrocarbons. On the other hand, two irradiated foods (papaya and mango which were irradiated at their practical doses) were difficult to distinguish from non-irradiated foods using this method. (author)

  15. Toxic hepatitis in occupational exposure to solvents

    Institute of Scientific and Technical Information of China (English)

    Giulia Malaguarnera; Emanuela Cataudella; Maria Giordano; Giuseppe Nunnari; Giuseppe Chisari; Mariano Malaguarnera

    2012-01-01

    The liver is the main organ responsible for the metabolism of drugs and toxic chemicals,and so is the primary target organ for many organic solvents.Work activities with hepatotoxins exposures are numerous and,moreover,organic solvents are used in various industrial processes.Organic solvents used in different industrial processes may be associated with hepatotoxicity.Several factors contribute to liver toxicity; among these are:species differences,nutritional condition,genetic factors,interaction with medications in use,alcohol abuse and interaction,and age.This review addresses the mechanisms of hepatotoxicity.The main pathogenic mechanisms responsible for functional and organic damage caused by solvents are:inflammation,dysfunction of cytochrome P450,mitochondrial dysfunction and oxidative stress.The health impact of exposure to solvents in the workplace remains an interesting and worrying question for professional health work.

  16. Assessment of solvents for cellulose dissolution.

    Science.gov (United States)

    Ghasemi, Mohammad; Tsianou, Marina; Alexandridis, Paschalis

    2017-03-01

    A necessary step in the processing of biomass is the pretreatment and dissolution of cellulose. A good solvent for cellulose involves high diffusivity, aggressiveness in decrystallization, and capability of disassociating the cellulose chains. However, it is not clear which of these factors and under what conditions should be improved in order to obtain a more effective solvent. To this end, a newly-developed phenomenological model has been applied to assess the controlling mechanism of cellulose dissolution. Among the findings, the cellulose fibers remain crystalline almost to the end of the dissolution process for decrystallization-controlled kinetics. In such solvents, decreasing the fiber crystallinity, e.g., via pretreatment, would result in a considerable increase in the dissolution rate. Such insights improve the understanding of cellulose dissolution and facilitate the selection of more efficient solvents and processing conditions for biomass. Specific examples of solvents are provided where dissolution is limited due to decrystallization or disentanglement.

  17. Preparation of coal slurry with organic solvents.

    Science.gov (United States)

    Shin, Yu-Jen; Shen, Yun-Hwei

    2007-06-01

    In this study, various organic solvents were used to prepare coal slurries and the rheological and thermal properties of coal-organic solvent slurries were examined. Solvents with molecules containing unpaired electrons (high basicity) show high extraction power and cause swelling of coal. Therefore, coal-organic solvent slurries usually showed higher viscosities compared to coal-water slurry. In addition, coal slurries prepared by alcohols and cyclohexanone demonstrated lower settling rates but a high specific sedimentation volume presumably because these solvents swelled coal particles well and led to the formation of weak gel structures in the bulk. In addition, ethanol and cyclohexanone are capable of breaking a considerable amount of hydrogen bonds in coal and subsequently opening up the structures. Thus, more surface area is available for combustion and the combustion rate of coal slurries was increased.

  18. Efficient cellulose solvent: quaternary ammonium chlorides.

    Science.gov (United States)

    Kostag, Marc; Liebert, Tim; El Seoud, Omar A; Heinze, Thomas

    2013-10-01

    Pure quaternary tetraalkylammonium chlorides with one long alkyl chain dissolved in various organic solvents constitute a new class of cellulose solvents. The electrolytes are prepared in high yields and purity by Menshutkin quaternization, an inexpensive and easy synthesis route. The pure molten tetraalkylammonium chlorides dissolve up to 15 wt% of cellulose. Cosolvents, including N,N-dimethylacetamide (DMA), may be added in large excess, leading to a system of decreased viscosity. Contrary to the well-established solvent DMA/LiCl, cellulose dissolves in DMA/quaternary ammonium chlorides without any pretreatment. Thus, the use of the new solvent avoids some disadvantages of DMA/LiCl and ionic liquids, the most extensively employed solvents for homogeneous cellulose chemistry.

  19. Green-solvent-processable organic solar cells

    Directory of Open Access Journals (Sweden)

    Shaoqing Zhang

    2016-11-01

    Full Text Available Solution-processable organic photovoltaics (OPV has emerged as a promising clean energy-generating technology due to its potential for low-cost manufacturing with a high power/weight ratio. The state-of-the-art OPV devices are processed by hazardous halogenated solvents. Fabricating high-efficiency OPV devices using greener solvents is a necessary step toward their eventual commercialization. In this review, recent research efforts and advances in green-solvent-processable OPVs are summarized, and two basic strategies including material design and solvent selection of light-harvesting layers are discussed. In particular, the most recent green-solvent-processable OPVs with high efficiencies in excess of 9% are highlighted.

  20. [Neurotoxicity of organic solvents--recent findings].

    Science.gov (United States)

    Matsuoka, Masato

    2007-06-01

    In this review, the recent findings of central nervous system (CNS) or peripheral nervous system (PNS) dysfunction induced by occupational exposure to organic solvents are described. While acute, high-level exposure to almost all organic solvents causes the general, nonspecific depression of CNS, it is still not clear whether chronic, low-level occupational exposure causes the chronic neurological dysfunction which has been called "organic solvent syndrome", "painters syndrome", "psycho-organic syndrome" or "chronic solvent encephalopathy". At least at lower than occupational exposure limits, chronic and low-level organic solvent exposure does not appear to cause the "sy mptomatic" neurological dysfunction. The chronic, moderate- to high-level exposure to a few organic solvents (such as carbon disulfide, n-hexane and methyl n-butyl ketone) affects CNS or PNS specifically. The substitutes for chlorofluorocarbons, 2-bromopropane and 1-bromopropane were shown to have the peripheral nerve toxicity in the experimental animals. Shortly after these observations, human cases of 1-bromopropane intoxication with the dysfunction of CNS and PNS were reported in the United States. Neurological abnormalities in workers of a 1-bromopropane factory in China were also reported. Thus, the possible neurotoxicity of newly introduced substitutes for ozone-depleting solvents into the workplace must be considered. Enough evidences indicate that some common solvents (such as toluene and styrene) induce sensorineural hearing loss and acquired color vision disturbances in workers. In some studies using magnetic resonance imaging (MRI), cerebral atrophy, patchy periventricular hyperintensities and hypointensities in the basal ganglia were found in solvent-exposed workers as have been shown in toluene abusers (toluene leukoencephalopathy). Further studies using the neurobehavioral test batteries, neurophysiological measurements and advanced neuroimaging techniques are required to detect the

  1. The chemistry of nonaqueous solvents v.4 solution phenomena and aprotic solvents

    CERN Document Server

    Lagowski, J J

    1976-01-01

    The Chemistry of Nonaqueous Solvents, Volume IV: Solution Phenomena and Aprotic Solvents focuses on the chemistry of nonaqueous solvents, with emphasis on solution phenomena and aprotic solvents such as tetramethylurea, inorganic acid chlorides, cyclic carbonates, and sulfolane. This book is organized into seven chapters and begins with an overview of the theory of electrical conductivity and elementary experimental considerations, along with some of the interesting research on nonaqueous solvents. It then turns to a discussion on hydrogen bonding phenomena in nonaqueous systems as probed

  2. PARIS II: Computer Aided Solvent Design for Pollution Prevention

    Science.gov (United States)

    This product is a summary of U.S. EPA researchers' work developing the solvent substitution software tool PARIS II (Program for Assisting the Replacement of Industrial Solvents, version 2.0). PARIS II finds less toxic solvents or solvent mixtures to replace more toxic solvents co...

  3. Applied bioremediation of petroleum hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Hinchee, R.E.; Kittel, J.A. [eds.] [Battelle Memorial Inst., Columbus, OH (United States); Reisinger, H.J. [ed.] [Integrated Science and Technology, Inc., Marietta, GA (United States)

    1995-12-31

    This volume is part of a ten volume set of papers derived from the Third International In Situ and On-Site Bioreclamation Symposium which was held in San Diego, California, in April 1995. The purpose of the conference was to provide a multidisciplinary forum for exchange of state-of-the-art information on bioremediation. The papers in this volume focus on petroleum hydrocarbon bioremediation, with an emphasis on pilot-scale and field-scale applications. Individual papers have been processed separately for inclusion in the appropriate data bases.

  4. Nile Red Detection of Bacterial Hydrocarbons and Ketones in a High-Throughput Format

    Energy Technology Data Exchange (ETDEWEB)

    Pinzon, NM; Aukema, KG; Gralnick, JA; Wackett, LP

    2011-06-28

    A method for use in high-throughput screening of bacteria for the production of long-chain hydrocarbons and ketones by monitoring fluorescent light emission in the presence of Nile red is described. Nile red has previously been used to screen for polyhydroxybutyrate (PHB) and fatty acid esters, but this is the first report of screening for recombinant bacteria making hydrocarbons or ketones. The microtiter plate assay was evaluated using wild-type and recombinant strains of Shewanella oneidensis and Escherichia coli expressing the enzyme OleA, previously shown to initiate hydrocarbon biosynthesis. The strains expressing exogenous Stenotrophomonas maltophilia oleA, with increased levels of ketone production as determined by gas chromatography-mass spectrometry, were distinguished with Nile red fluorescence. Confocal microscopy images of S. oneidensis oleA-expressing strains stained with Nile red were consistent with a membrane localization of the ketones. This differed from Nile red staining of bacterial PHB or algal lipid droplets that showed intracellular inclusion bodies. These results demonstrated the applicability of Nile red in a high-throughput technique for the detection of bacterial hydrocarbons and ketones. IMPORTANCE In recent years, there has been renewed interest in advanced biofuel sources such as bacterial hydrocarbon production. Previous studies used solvent extraction of bacterial cultures followed by gas chromatography-mass spectrometry (GC-MS) to detect and quantify ketones and hydrocarbons (Beller HR, Goh EB, Keasling JD, Appl. Environ. Microbiol. 76: 1212-1223, 2010; Sukovich DJ, Seffernick JL, Richman JE, Gralnick JA, Wackett LP, Appl. Environ. Microbiol. 76: 3850-3862, 2010). While these analyses are powerful and accurate, their labor-intensive nature makes them intractable to high-throughput screening; therefore, methods for rapid identification of bacterial strains that are overproducing hydrocarbons are needed. The use of high

  5. Predicting the Solubility of Pharmaceutical Cocrystals in Solvent/Anti-Solvent Mixtures

    Directory of Open Access Journals (Sweden)

    Linda Lange

    2016-05-01

    Full Text Available In this work, the solubilities of pharmaceutical cocrystals in solvent/anti-solvent systems were predicted using PC-SAFT in order to increase the efficiency of cocrystal formation processes. Modeling results and experimental data were compared for the cocrystal system nicotinamide/succinic acid (2:1 in the solvent/anti-solvent mixtures ethanol/water, ethanol/acetonitrile and ethanol/ethyl acetate at 298.15 K and in the ethanol/ethyl acetate mixture also at 310.15 K. The solubility of the investigated cocrystal slightly increased when adding small amounts of anti-solvent to the solvent, but drastically decreased for high anti-solvent amounts. Furthermore, the solubilities of nicotinamide, succinic acid and the cocrystal in the considered solvent/anti-solvent mixtures showed strong deviations from ideal-solution behavior. However, by accounting for the thermodynamic non-ideality of the components, PC-SAFT is able to predict the solubilities in all above-mentioned solvent/anti-solvent systems in good agreement with the experimental data.

  6. Measurement of activity coefficients at infinite dilution for hydrocarbons in imidazolium-based ionic liquids and QSPR model

    Institute of Scientific and Technical Information of China (English)

    ZHU Jiqin; YU Yanmei; CHEN Jian; FEI Weiyang

    2007-01-01

    The separations of olefin/paraffin,aromatic/aliphatic hydrocarbons or olefin isomers using ionic liquids instead of volatile solvents have interested many researchers.Activity coefficients γ∞ at infinite dilution of a solute in ionic liquid are generally used in the selection of solvents for extraction or extractive distillation.In fact,the measurement of γ∞ by gas-liquid chromatography is a speedy and costsaving method.Activity coefficients at infinite dilution of hydrocarbon solutes,such as alkanes,hexenes,alkylbenzenes,styrene,in 1-allyl-3-methylimidazolium tetrafluoroborate ([AMIM][BF4]) and 1-butyl-3-methyl imidazolium hexafluorophosphate ([BMIM][PF6]), 1-isobutenyl-3-methylimidazolium tetrafluoroborate ([MPMIM][BF4]) and [MPMIM][BF4]-AgBF4 have been determined by gas-liquid chromatography using ionic liquids as stationary phase.The measurements were carried out at different temperatures from 298 to 318 K.The separating effects of these ionic liquids for alkanes/hexane,aliphatic hydrocarbons/benzene and hexene isomers have been discussed.The hydrophobic parameter,dipole element,frontier molecular orbital energy gap and hydration energy of these hydrocarbons were calculated with the PM3 semi-empirical quantum chemistry method.The quantitative relations among the computed structure parameters and activity coefficients at infinite dilution were also developed.The experimental activity coefficient data are consistent with the correlated and predicted results using QSPR models.

  7. Sequential biodegradation of complex naphtha hydrocarbons under methanogenic conditions in two different oil sands tailings.

    Science.gov (United States)

    Mohamad Shahimin, Mohd Faidz; Siddique, Tariq

    2017-02-01

    Methane emissions in oil sands tailings ponds are sustained by anaerobic biodegradation of unrecovered hydrocarbons. Naphtha (primarily C6-C10; n- iso- and cycloalkanes) is commonly used as a solvent during bitumen extraction process and its residue escapes to tailings ponds during tailings deposition. To investigate biodegradability of hydrocarbons in naphtha, mature fine tailings (MFT) collected from Albian and CNRL tailings ponds were amended with CNRL naphtha at ∼0.2 wt% (∼2000 mg L(-1)) and incubated under methanogenic conditions for ∼1600 d. Microbial communities in both MFTs started metabolizing naphtha after a lag phase of ∼100 d. Complete biodegradation/biotransformation of all n-alkanes (except partial biodegradation of n-octane in CNRL MFT) followed by major iso-alkanes (2-methylpentane, 3-methylhexane, 2- and 4-methylheptane, iso-nonanes and 2-methylnonane) and a few cycloalkanes (derivatives of cyclopentane and cyclohexane) was observed during the incubation. 16S rRNA gene pyrosequencing showed dominance of Peptococcaceae and Anaerolineaceae in Albian MFT and Anaerolineaceae and Syntrophaceae in CNRL MFT bacterial communities with co-domination of Methanosaetaceae and "Candidatus Methanoregula" in archaeal populations during active biodegradation of hydrocarbons. The findings extend the known range of hydrocarbons susceptible to methanogenic biodegradation in petroleum-impacted anaerobic environments and help refine existing kinetic model to predict greenhouse gas emissions from tailings ponds. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2014-01-01

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

  9. The specific carbon isotopic compositions of branched and cyclic hydrocarbons from Fushun oil shale

    Institute of Scientific and Technical Information of China (English)

    DUAN Yi; WU Baoxiang; ZHENG Guodong; ZHANG Hui; ZHENG Chaoyang

    2004-01-01

    Various branched and cyclic hydrocarbons are isolated from the Fushun oil shale and their carbon isotopes are determined. The analytical results show that the branched and cyclic hydrocarbons are fully separated from n-alkanes by 5 A Molecular-sieve adduction using long time and cold solvent. The branched and cyclic hydrocarbon fraction obtained by this method is able to satisfy the analytic requests of GC-IRMS. The carbon isotopic compositions of these branched and cyclic hydrocarbons obtained from the sample indicate that they are derived from photoautotrophic algae, chemoautotrophic bacteria (-3.4‰ --39.0‰) and methanotrophic bacteria (-38.4‰--46.3‰). However the long-chain 2-methyl-branched alkanes indicate that their carbon isotopic compositions reflect biological origin from higher plants. The carbon isotopic composition of C30 4-methyl sterane (-22.1‰) is the heaviest in all studied ste- ranes, showing that the carbon source or growth condition for its precursor, dinoflagellate, may be different from that of regular steranes. The variation trend of δ13C values between isomers of hopanes shows that 13C-enriched precursors take precedence in process of their epimerization. Methanotrophic hopanes presented reveal the processes of strong transformation of organic matter and cycling of organic carbon in the water column and early diagenesis of oil shale.

  10. 40 CFR 52.1877 - Control strategy: Photochemical oxidants (hydrocarbons).

    Science.gov (United States)

    2010-07-01

    ... oxidants (hydrocarbons). 52.1877 Section 52.1877 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY....1877 Control strategy: Photochemical oxidants (hydrocarbons). (a) The requirements of Subpart G of this... national standard for photochemical oxidants (hydrocarbons) in the Metropolitan Cincinnati...

  11. Effectiveness of isopropyl myristate/cyclomethicone D5 solution of removing cuticular hydrocarbons from human head lice (Pediculus humanus capitis

    Directory of Open Access Journals (Sweden)

    Barnett Eric

    2012-09-01

    Full Text Available Abstract Background In the treatment of human head lice infestation, healthcare providers are increasingly concerned about lice becoming resistant to existing pesticide treatments. Traditional pesticides, used to control these pests, have a neurological mechanism of action. This publication describes a topical solution with a non-traditional mechanism of action, based on physical disruption of the wax layer that covers the cuticle of the louse exoskeleton. This topical solution has been shown clinically to cure 82% of patients with only a 10-minute treatment time, repeated once after 7 days. All insects, including human head lice, have a wax-covered exoskeleton. This wax, composed of hydrocarbons, provides the insect with protection against water loss and is therefore critical to its survival. When the protective wax is disrupted, water loss becomes uncontrollable and irreversible, leading to dehydration and death. A specific pattern of hydrocarbons has been found in all of the head louse cuticular wax studied. Iso-octane effectively removes these hydrocarbons from human head lice’s cuticular wax. Methods A method of head louse cuticle wax extraction and analysis by gas chromatography was developed. Human head lice (Pediculus humanus capitis were collected from infested patients and subjected to any of three extraction solvents comprising either the test product or one of two solvents introduced as controls. A gas chromatograph equipped with a flame ionization detector (GC/FID was used to determine the presence of hydrocarbons in the three head lice extracts. Results In the study reported herein, the test product isopropyl myristate/cyclomethicone D5 (IPM/D5 was shown to perform comparably with iso-octane, effectively extracting the target hydrocarbons from the cuticular wax that coats the human head louse exoskeleton. Conclusions Disruption of the integrity of the insect cuticle by removal of specific hydrocarbons found in the cuticular wax

  12. Method for estimating processability of a hydrocarbon-containing feedstock for hydroprocessing

    Science.gov (United States)

    Schabron, John F; Rovani, Jr., Joseph F

    2014-01-14

    Disclosed herein is a method involving the steps of (a) precipitating an amount of asphaltenes from a liquid sample of a first hydrocarbon-containing feedstock having solvated asphaltenes therein with one or more first solvents in a column; (b) determining one or more solubility characteristics of the precipitated asphaltenes; (c) analyzing the one or more solubility characteristics of the precipitated asphaltenes; and (d) correlating a measurement of feedstock reactivity for the first hydrocarbon-containing feedstock sample with a mathematical parameter derived from the results of analyzing the one or more solubility characteristics of the precipitates asphaltenes. Determined parameters and processabilities for a plurality of feedstocks can be used to generate a mathematical relationship between parameter and processability; this relationship can be used to estimate the processability for hydroprocessing for a feedstock of unknown processability.

  13. Fractional Multistage Hydrothermal Liquefaction of Biomass and Catalytic Conversion into Hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Cortright, Randy; Rozmiarek, Robert; Dally, Brice; Holland, Chris

    2017-08-31

    The objective of this project was to develop an improved multistage process for the hydrothermal liquefaction (HTL) of biomass to serve as a new front-end, deconstruction process ideally suited to feed Virent’s well-proven catalytic technology, which is already being scaled up. This process produced water soluble, partially de-oxygenated intermediates that are ideally suited for catalytic finishing to fungible distillate hydrocarbons. Through this project, Virent, with its partners, demonstrated the conversion of pine wood chips to drop-in hydrocarbon distillate fuels using a multi-stage fractional conversion system that is integrated with Virent’s BioForming® process. The majority of work was in the liquefaction task and included temperature scoping, solvent optimization, and separations.

  14. Polycyclic aromatic hydrocarbons connected with Schiff base linkers: Experimental and theoretical photophysical characterization and electrochemical properties

    Science.gov (United States)

    Sęk, Danuta; Siwy, Mariola; Małecki, Jan Grzegorz; Kotowicz, Sonia; Golba, Sylwia; Nowak, Elżbieta M.; Sanetra, Jerzy; Schab-Balcerzak, Ewa

    2017-03-01

    A series of polyaromatic hydrocarbons with anthracene, phenanthrene and pyrene units connected with Schiff base junctions were synthesized via condensation of p-phenylenediamine and hydrazine with selected aldehydes. The effect of both hydrocarbon structures and presence of N-N- or phenyl- linked diimines on properties of the prepared azines and azomethines was analyzed. The obtained compounds were soluble in common organic solvents and melted in the range of 226-317 °C. Their photophysical and electrochemical properties were investigated by UV-vis, photoluminescence spectroscopies and cyclic voltammetry (CV), respectively. Moreover, a density functional theory (DFT) was applied for calculation of their electronic and geometric structures as well as absorption and emission spectra. Additionally, their electron acceptor activity was preliminary tested in photovoltaic experiment.

  15. Hydrocarbon conversion process and catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Hoek, A.; Huizinga, T.; Maxwell, I.E.

    1989-08-15

    This patent describes a process for hydrocracking hydrocarbon oils into products of lower average molecular weight and lower average boiling point. It comprises contacting hydrocarbon oil at a temperature between 250{sup 0}C and 500{sup 0}C and a pressure up to 300 bar in the presence of hydrogen with a catalyst consisting essentially of a Y zeolite modified to have a unit cell size below 24.40 A, a water adsorption capacity (at 25{sup 0}C and a rho/rho/sub o/ value of 0.2) of between 10% and 15% by weight of the zeolite and a pore volume of at least 0.25 ml/g wherein between 10% and 60% of the total pore volume is made up of pores having a diameter of at least 8 nm; am amorphous cracking component, a binder and at least one hydrogenation component selected from the group consisting of a Group VI metal, a Group VIII metal and mixtures thereof.

  16. Hydrocarbon degradation by antarctic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Cavanagh, J.A.E.; Nichols, P.D.; McMeekin, T.A.; Franzmann, P.D. [Univ. of Tasmania (Australia)] [and others

    1996-12-31

    Bacterial cultures obtained from sediment samples collected during a trial oil spill experiment conducted at Airport beach, Eastern Antarctica were selectively enriched for n-alkane-degrading and phenanthrenedegrading bacteria. Samples were collected from a control site and sites treated with different hydrocarbon mixtures - Special Antarctic blend (SAB), BP-Visco and orange roughy oils. One set of replicate sites was also treated with water from Organic Lake which had previously been shown to contain hydrocarbon-degrading bacteria. No viable bacteria were obtained from samples collected from sites treated with orange roughy oil. Extensive degradation of n-alkanes by enrichment cultures obtained from sites treated with SAB and BP-Visco occurred at both 25{degrees}C and 10{degrees}C. Extensive degradation of phenanthrene also occurred in enrichment cultures from these sites grown at 25{degrees}C. Concurrent increases of polar lipid in these cultures were also observed. The presence of 1,4-naphthaquinone and 1-naphthol during the growth of the cultures on phenanthrene is unusual and warrants further investigation of the mechanism of phenanthrene-degradation by these Antarctic bacteria.

  17. Cool Sooting Flames of Hydrocarbons

    Institute of Scientific and Technical Information of China (English)

    Z.A. MANSUROV

    2001-01-01

    This paper presents the study of polycyclic aromatic hydrocarbons (PAH) and paramagnetism of soot particles sampled from cool sooting flames of methane and propane in a separately-heated two-sectional reactor under atmospheric pressure at the reactor temperatures of 670-1170 K. The temperature profiles of the flames were studied. The sampling was carried out with a quartz sampler and the samples were frozen with liquid nitrogen. A number of polyaromatic hydrocarbons such as pyrene, fluoranthene, coronene, anthanthrene, 1,12-benzperylene,were identified by spectroscopic methods in the extract of soot. The processes of soot formation at methaneoxygen mixture combustion in the electric field with applied potential changed from 0 to 2,2 kV at different polarity of electrodes have been investigated. It has been stated that at the electrical field application, an increase in soot particle sizes and soot yield occurs; besides, at the application of the field, speeding up the positively charged particles, the interplanar distance decreases. On the basis of investigation of soot particles paramagnetism, it was shown that initially soot particles have high carcinogetic activity and pollute the environment owing to a rapid decrease of the number of these radical centers. The reduction of the radical concentration is connected with radical recombination on soot.

  18. Organic Solvent Tolerant Lipases and Applications

    Directory of Open Access Journals (Sweden)

    Shivika Sharma

    2014-01-01

    Full Text Available Lipases are a group of enzymes naturally endowed with the property of performing reactions in aqueous as well as organic solvents. The esterification reactions using lipase(s could be performed in water-restricted organic media as organic solvent(s not only improve(s the solubility of substrate and reactant in reaction mixture but also permit(s the reaction in the reverse direction, and often it is easy to recover the product in organic phase in two-phase equilibrium systems. The use of organic solvent tolerant lipase in organic media has exhibited many advantages: increased activity and stability, regiospecificity and stereoselectivity, higher solubility of substrate, ease of products recovery, and ability to shift the reaction equilibrium toward synthetic direction. Therefore the search for organic solvent tolerant enzymes has been an extensive area of research. A variety of fatty acid esters are now being produced commercially using immobilized lipase in nonaqueous solvents. This review describes the organic tolerance and industrial application of lipases. The main emphasis is to study the nature of organic solvent tolerant lipases. Also, the potential industrial applications that make lipases the biocatalysts of choice for the present and future have been presented.

  19. Polar Solvents Trigger Formation of Reverse Micelles.

    Science.gov (United States)

    Khoshnood, Atefeh; Firoozabadi, Abbas

    2015-06-09

    We use molecular dynamics simulations and molecular thermodynamics to investigate the formation of reverse micelles in a system of surfactants and nonpolar solvents. Since the early observation of reverse micelles, the question has been whether the existence of polar solvent molecules such as water is the driving force for the formation of reverse micelles in nonpolar solvents. In this work, we use a simple coarse-grained model of surfactants and solvents to show that a small number of polar solvent molecules triggers the formation of large permanent aggregates. In the absence of polar molecules, both the thermodynamic model and molecular simulations show that small aggregates are more populated in the solution and larger ones are less frequent as the system evolves over time. The size and shape of reverse micelles depend on the size of the polar core: the shape is spherical for a large core and ellipsoidal for a smaller one. Using the coarse-grained model, we also investigate the effect of temperature and surfactant tail length. Our results reveal that the number of surfactant molecules in the micelle decreases as the temperature increases, but the average diameter does not change because the size of the polar core remains invariant. A reverse micelle with small polar core attracts fewer surfactants when the tail is long. The uptake of solvent particles by a micelle of longer surfactant tail is less than shorter ones when the polar solvent particles are initially distributed randomly.

  20. Auditory dysfunction associated with solvent exposure

    Directory of Open Access Journals (Sweden)

    Fuente Adrian

    2013-01-01

    Full Text Available Abstract Background A number of studies have demonstrated that solvents may induce auditory dysfunction. However, there is still little knowledge regarding the main signs and symptoms of solvent-induced hearing loss (SIHL. The aim of this research was to investigate the association between solvent exposure and adverse effects on peripheral and central auditory functioning with a comprehensive audiological test battery. Methods Seventy-two solvent-exposed workers and 72 non-exposed workers were selected to participate in the study. The test battery comprised pure-tone audiometry (PTA, transient evoked otoacoustic emissions (TEOAE, Random Gap Detection (RGD and Hearing-in-Noise test (HINT. Results Solvent-exposed subjects presented with poorer mean test results than non-exposed subjects. A bivariate and multivariate linear regression model analysis was performed. One model for each auditory outcome (PTA, TEOAE, RGD and HINT was independently constructed. For all of the models solvent exposure was significantly associated with the auditory outcome. Age also appeared significantly associated with some auditory outcomes. Conclusions This study provides further evidence of the possible adverse effect of solvents on the peripheral and central auditory functioning. A discussion of these effects and the utility of selected hearing tests to assess SIHL is addressed.

  1. Solvent Effect on the Photolysis of Riboflavin.

    Science.gov (United States)

    Ahmad, Iqbal; Anwar, Zubair; Ahmed, Sofia; Sheraz, Muhammad Ali; Bano, Raheela; Hafeez, Ambreen

    2015-10-01

    The kinetics of photolysis of riboflavin (RF) in water (pH 7.0) and in organic solvents (acetonitrile, methanol, ethanol, 1-propanol, 1-butanol, ethyl acetate) has been studied using a multicomponent spectrometric method for the assay of RF and its major photoproducts, formylmethylflavin and lumichrome. The apparent first-order rate constants (k obs) for the reaction range from 3.19 (ethyl acetate) to 4.61 × 10(-3) min(-1) (water). The values of k obs have been found to be a linear function of solvent dielectric constant implying the participation of a dipolar intermediate along the reaction pathway. The degradation of this intermediate is promoted by the polarity of the medium. This indicates a greater stabilization of the excited-triplet states of RF with an increase in solvent polarity to facilitate its reduction. The rate constants for the reaction show a linear relation with the solvent acceptor number indicating the degree of solute-solvent interaction in different solvents. It would depend on the electron-donating capacity of RF molecule in organic solvents. The values of k obs are inversely proportional to the viscosity of the medium as a result of diffusion-controlled processes.

  2. Biological quality of soils containing hydrocarbons and efficacy of ecological risk reduction by bioremediation alternatives

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, A.J.; Napolitano, G.E.; Sample, B.E.

    1996-06-01

    This project provides technical support to the Petroleum Environmental Research Forum (PERF; a consortium of petroleum companies) on environmentally acceptable endpoints that may be used to help assess the ecological risk of petroleum hydrocarbon residuals in soils. The project, was designed in consultation with PERF representatives and focuses on the relationship between {open_quotes}chemically available{close_quotes} and {open_quotes}biologically available{close_quotes} measurements of petroleum hydrocarbon compounds in soils, a discrepancy of considerable interest to the petroleum industry. Presently, clean-up standards for soils contaminated with total petroleum hydrocarbon (TPH) constituents are based on concentrations of TPH, as measured in solvent extracts of soil samples. Interestingly, TPH includes a complex mixture of compounds which differ from one another in molecular weight and toxicity. Based on various studies with insecticides, herbicides and metals, some compounds apparently can slowly permeate into soil particles. If this situation occurs, the particle-embedded compounds may be extractable by use of organic solvents, and yet be unavailable biologically. This hypothesis serves as the central focus for our study. If this hypothesis is correct, then soil clean-up standards based on solvent-extractable TPH data may be more stringent than necessary to achieve a desired level of environmental risk. The economic significance of this possibility is considerable, because clean-up costs to achieve a low-risk status would, in most cases, be lower than those needed to achieve a standard based on present limits, which are based on measurements of {open_quotes}extractable{close_quotes} TPH.

  3. Conversion of organic solids to hydrocarbons

    Science.gov (United States)

    Greenbaum, Elias

    1995-01-01

    A method of converting organic solids to liquid and gaseous hydrocarbons includes impregnating an organic solid with photosensitizing ions and exposing the impregnated solid to light in a non-oxidizing atmosphere for a time sufficient to photocatalytically reduce the solid to at least one of a liquid and a gaseous hydrocarbon.

  4. Versatility of hydrocarbon production in cyanobacteria.

    Science.gov (United States)

    Xie, Min; Wang, Weihua; Zhang, Weiwen; Chen, Lei; Lu, Xuefeng

    2017-02-01

    Cyanobacteria are photosynthetic microorganisms using solar energy, H2O, and CO2 as the primary inputs. Compared to plants and eukaryotic microalgae, cyanobacteria are easier to be genetically engineered and possess higher growth rate. Extensive genomic information and well-established genetic platform make cyanobacteria good candidates to build efficient biosynthetic pathways for biofuels and chemicals by genetic engineering. Hydrocarbons are a family of compounds consisting entirely of hydrogen and carbon. Structural diversity of the hydrocarbon family is enabled by variation in chain length, degree of saturation, and rearrangements of the carbon skeleton. The diversified hydrocarbons can be used as valuable chemicals in the field of food, fuels, pharmaceuticals, nutrition, and cosmetics. Hydrocarbon biosynthesis is ubiquitous in bacteria, yeasts, fungi, plants, and insects. A wide variety of pathways for the hydrocarbon biosynthesis have been identified in recent years. Cyanobacteria may be superior chassis for hydrocabon production in a photosynthetic manner. A diversity of hydrocarbons including ethylene, alkanes, alkenes, and terpenes can be produced by cyanobacteria. Metabolic engineering and synthetic biology strategies can be employed to improve hydrocarbon production in cyanobacteria. This review mainly summarizes versatility and perspectives of hydrocarbon production in cyanobacteria.

  5. Primary biodegradation of petroleum hydrocarbons in seawater

    Energy Technology Data Exchange (ETDEWEB)

    Comber, M.I.H.; Den Haan, K.H.; Djemel, N.; Eadsforth, C.V.; King, D.; Paumen, M.L.; Parkerton, T.; Dmytrasz, B.

    2012-12-15

    This report describes primary biodegradation experiments performed to determine the persistence of higher molecular weight petroleum hydrocarbons in seawater. Results from the biodegradation experiments show that the majority of tested petroleum hydrocarbons have half-lives in seawater less than 60 days.

  6. Chemical reactions in solvents and melts

    CERN Document Server

    Charlot, G

    1969-01-01

    Chemical Reactions in Solvents and Melts discusses the use of organic and inorganic compounds as well as of melts as solvents. This book examines the applications in organic and inorganic chemistry as well as in electrochemistry. Organized into two parts encompassing 15 chapters, this book begins with an overview of the general properties and the different types of reactions, including acid-base reactions, complex formation reactions, and oxidation-reduction reactions. This text then describes the properties of inert and active solvents. Other chapters consider the proton transfer reactions in

  7. Modeling of Salt Solubilities in Mixed Solvents

    DEFF Research Database (Denmark)

    Chiavone-Filho, O.; Rasmussen, Peter

    2000-01-01

    A method to correlate and predict salt solubilities in mixed solvents using a UNIQUAC+Debye-Huckel model is developed. The UNIQUAC equation is applied in a form with temperature-dependent parameters. The Debye-Huckel model is extended to mixed solvents by properly evaluating the dielectric...... constants and the liquid densities of the solvent media. To normalize the activity coefficients, the symmetric convention is adopted. Thermochemical properties of the salt are used to estimate the solubility product. It is shown that the proposed procedure can describe with good accuracy a series of salt...

  8. Modeling of Salt Solubilities in Mixed Solvents

    DEFF Research Database (Denmark)

    Chiavone-Filho, O.; Rasmussen, Peter

    2000-01-01

    A method to correlate and predict salt solubilities in mixed solvents using a UNIQUAC+Debye-Huckel model is developed. The UNIQUAC equation is applied in a form with temperature-dependent parameters. The Debye-Huckel model is extended to mixed solvents by properly evaluating the dielectric...... constants and the liquid densities of the solvent media. To normalize the activity coefficients, the symmetric convention is adopted. Thermochemical properties of the salt are used to estimate the solubility product. It is shown that the proposed procedure can describe with good accuracy a series of salt...

  9. Supercritical CO2 as a substitute of volatile hydrocarbons; Superkritisch CO2 vervangt vluchtige koolwaterstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Folkerts, G. (ed.)

    2006-05-15

    In many cases supercritical carbon dioxide can replace volatile hydrocarbons in extraction processes. Currently gaseous or liquid CO2 is already used for industrial purification processes, extraction of caffeine from coffee and as a solvent for paint. Although supercritical extraction s a batch process the technique can be applied as a continuous process. [Dutch] In processen waar vluchtige koolwaterstoffen worden ingezet om stoffen te extraheren, biedt superkritisch CO2 een milieuvriendelijk alternatief. Het koolzuur dat zowel in de vloeistof- als gasfase zit, wordt dan ook steeds meer ingezet in extractieprocessen.

  10. Features of the micellar solubility of metal-containing surfactants in hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, A.B.; Zdobnova, O.L.; Zaichenko, L.P.; Proskuryakov, V.A.

    1988-03-10

    Metal-containing surfactants (SF) are now widely used as different additives to oils and fuels. The micellar solubility of a series of individual metal-containing SF and widely used additives was investigated as a function of the structure and polarity of the additive, type of hydrocarbon solvent, and presence of water in this study. Individual decyl benzenesulfonates (DBS) of different metals and samples of surfactant additives for oils of the alkylphenolate (VNII NP-370), sulfonate (PMSA, PMSya, S-150, S-300, Lubrizol 58, SB-3, PMSya (bariated), alkylsalicylate (ASK, MASK), and dialkyldithiophosphate (DF-11, VNII NP-354) types were investigated.

  11. SEQUESTRATION AND TREATMENT OF VADOSE ZONE SOLVENTS USING EDIBLE OILS

    Energy Technology Data Exchange (ETDEWEB)

    Riha, B; Brian02 Looney, B; Richard Hall (NOEMAIL), R

    2008-03-28

    Edible oils have emerged as an effective treatment amendment for a variety of contaminants. When applied to chlorinated volatile organic compounds (cVOCs) in the saturated zone, edible oils have been shown to enhance anaerobic bioremediation and sequester the contaminants. However, edible oils have not been applied to the vadose zone for contaminant treatment. Soybean oil was injected into the vadose zone in M-Area at the Department of Energy's (DOE) Savannah River Site (SRS) as a research study to evaluate the effectiveness of edible oils for solvent sequestration and the ability to change a vadose system from aerobic to anaerobic to initiate reductive dechlorination. The proposed use of this technique would be an enhanced attenuation/transition step after active remediation. The goals of the research were to evaluate oil emplacement methods and monitoring techniques to measure oil placement, partitioning and degradation. Gas sampling was the cornerstone for this evaluation. Analyses for cVOCs and biotransformation products were performed. Overall, the cVOC concentration/flux reduction was 75-85% in this vadose zone setting. Destruction of the cVOCs by biotic or abiotic process has not yet been verified at this site. No reductive dechlorination products have been measured. The deployment has resulted in a substantial generation of light hydrocarbon gases and geochemical conditions that would support cometabolism.

  12. Extraction agents for the removal of polycyclic aromatic hydrocarbons (PAHs) from soil in soil washing technologies.

    Science.gov (United States)

    Lau, Ee Von; Gan, Suyin; Ng, Hoon Kiat; Poh, Phaik Eong

    2014-01-01

    Polycyclic aromatic hydrocarbons (PAHs) in soil have been recognised as a serious health and environmental issue due to their carcinogenic, mutagenic and teratogenic properties. One of the commonly employed soil remediation techniques to clean up such contamination is soil washing or solvent extraction. The main factor which governs the efficiency of this process is the solubility of PAHs in the extraction agent. Past field-scale soil washing treatments for PAH-contaminated soil have mainly employed organic solvents or water which is either toxic and costly or inefficient in removing higher molecular weight PAHs. Thus, the present article aims to provide a review and discussion of the alternative extraction agents that have been studied, including surfactants, biosurfactants, microemulsions, natural surfactants, cyclodextrins, vegetable oil and solution with solid phase particles. These extraction agents have been found to remove PAHs from soil at percentages ranging from 47 to 100% for various PAHs.

  13. Inclusion of poly-aromatic hydrocarbon (PAH) molecules in a functionalized layered double hydroxide

    Indian Academy of Sciences (India)

    L Mohanambe; S Vasudevan

    2006-01-01

    The internal surface of an Mg-Al layered double hydroxide has been functionalized by anchoring carboxy-methyl derivatized -cyclodextrin cavities to the gallery walls. Neutral polyaromatic hydrocarbon (PAH) molecules have been included within the functionalized solid by driving the hydrophobic aromatic molecules from a polar solvent into the less polar interior of the anchored cyclodextrin cavities by a partitioning process. The optical (absorption and emission) properties of the PAH molecules included within the functionalized Mg-Al layered double hydroxide solid are similar to that of dilute solutions of the PAH in non-polar solvents. The unique feature of these hybrid materials is that they are thermally stable over a wide temperature range with their emission properties practically unaltered.

  14. Development and certification of a coal fly ash certified reference material for selected polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Cao, X; Xu, X; Cui, W; Xi, Z

    2001-08-01

    The development and certification of a coal fly ash certified reference material (CRM) for polycyclic aromatic hydrocarbons (PAH) is described; this is the first natural matrix CRM for organic environmental analysis in China. The homogeneity and stability of this material have been tested by HPLC. The concentrations of several PAH were determined by use of two independent, different methods--solvent extraction-HPLC analysis with UV detection coupled with fluorescence detection (FLD) and solvent extraction, isolation with a silica column, and GC analysis with flame ionization detection (FID). Five certified values were determined: phenanthrene 7.1 +/- 2.6 microg g(-1), anthracene 2.0 +/- 0.8 microg g(-1), fluoranthene 7.4 +/- 1.9 microg g(-1), pyrene 7 +/- 2 microg g(-1), and benzo[a]pyrene 1.3 +/- 0.3 microg g(-1). Reference values for several other PAH are also suggested.

  15. Solvent exposure and malignant lymphoma: a population-based case-control study in Germany

    Directory of Open Access Journals (Sweden)

    Deeg Evelin

    2007-04-01

    Full Text Available Abstract Aims To analyze the relationship between exposure to chlorinated and aromatic organic solvents and malignant lymphoma in a multi-centre, population-based case-control study. Methods Male and female patients with malignant lymphoma (n = 710 between 18 and 80 years of age were prospectively recruited in six study regions in Germany (Ludwigshafen/Upper Palatinate, Heidelberg/Rhine-Neckar-County, Würzburg/Lower Frankonia, Hamburg, Bielefeld/Gütersloh, and Munich. For each newly recruited lymphoma case, a gender, region and age-matched (± 1 year of birth population control was drawn from the population registers. In a structured personal interview, we elicited a complete occupational history, including every occupational period that lasted at least one year. On the basis of job task-specific supplementary questionnaires, a trained occupational physician assessed the exposure to chlorinated hydrocarbons (trichloroethylene, tetrachloroethylene, dichloromethane, carbon tetrachloride and aromatic hydrocarbons (benzene, toluene, xylene, styrene. Odds ratios (OR and 95% confidence intervals (CI were calculated using conditional logistic regression analysis, adjusted for smoking (in pack years and alcohol consumption. To increase the statistical power, patients with specific lymphoma subentities were additionally compared with the entire control group using unconditional logistic regression analysis. Results We observed a statistically significant association between high exposure to chlorinated hydrocarbons and malignant lymphoma (Odds ratio = 2.1; 95% confidence interval 1.1–4.3. In the analysis of lymphoma subentities, a pronounced risk elevation was found for follicular lymphoma and marginal zone lymphoma. When specific substances were considered, the association between trichloroethylene and malignant lymphoma was of borderline statistical significance. Aromatic hydrocarbons were not significantly associated with the lymphoma diagnosis

  16. Occurrence of aliphatic and polyaromatic hydrocarbons (PAHs) in Mytillus galloprovincialis from the traditional market in Marseille, France, by Gas Chromatography triplequadropole tandem Mass Spectrometry (GC-QQQ/MS)

    Science.gov (United States)

    Azis, M. Y.; Yelmiza; Asia, L.; Piram, A.; Bucharil, B.; Doumenq, P.; Syakti, A. D.

    2016-02-01

    Mediterranean mussel, Mytillusgalloprovincialis collected from the traditional market in Marseille, France,have been analysed using GC-QQQ/MS for their hydrocarbons (n-alkanes and polyaromatic hydrocarbons (PAHs)) extentwith two different solvent extraction, such as heptane:dichloromethane (HEP:DCM;1:1) and heptane:acetone (HEP:ACE; 1:1). The results showed hydrocarbons yielded from heptane:acetone extractionwere 28335 μg.kg- 1mussels dw (Ʃ n-alkanes C15-34) and 202 μg.kg-1mussels dw(ƩPAHs) while the yield from heptane:DCM extract was lower ca. 27026 μg.kg-1musselsdw and 133 μg.kg-1 mussels dw respectively from the Ʃn-alkanesC15-34and ƩPAHs. High hydrocarbon levels can be affected by the presence of lipids or other metabolites in mussels that have the same polarity with hydrocarbon compounds which has interferred the measurement. Several ratio parameter of n- alcanes and PAHs source in the mussels were evaluated to asses the origins of their hydrocarbons in mussels from which we suggested origins of hydrocarbons were pyrolytic and biogenic rather than petrogenic.

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

    Directory of Open Access Journals (Sweden)

    S. Reimann

    2008-05-01

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

  18. Selective Synthesis of Gasoline-Ranged Hydrocarbons from Syngas over Hybrid Catalyst Consisting of Metal-Loaded ZSM-5 Coupled with Copper-Zinc Oxide

    Directory of Open Access Journals (Sweden)

    Ting Ma

    2014-04-01

    Full Text Available The conversion of syngas (CO + H2 to gasoline-ranged hydrocarbons was carried out using a hybrid catalyst consisting of metal-loaded ZSM-5 coupled with Cu-ZnO in a near-critical n-hexane solvent. Methanol was synthesized from syngas over Cu-ZnO; subsequently, was converted to hydrocarbons through the formation of dimethyl ether (DME over the metal-loaded ZSM-5. When 0.5 wt% Pd/ZSM-5 and 5 wt% Cu/ZSM-5 among the metal-loaded ZSM-5 catalysts with Pd, Co, Fe or Cu were employed as a portion of the hybrid catalyst, the gasoline-ranged hydrocarbons were selectively produced (the gasoline-ranged hydrocarbons in all hydrocarbons: 59% for the hybrid catalyst with Pd/ZSM-5 and 64% for that with Cu/ZSM-5 with a similar CO conversion during the reaction. An increase in the Cu loading on ZSM-5 resulted in increasing the yield of the gasoline-ranged hydrocarbons, and in decreasing the yield of DME. Furthermore, the hybrid catalyst with Cu/ZSM-5 exhibited no deactivation for 30 h of the reaction. It was revealed that a hybrid catalyst containing Cu/ZSM-5 was efficient in the selective synthesis of gasoline-ranged hydrocarbons from syngas via methanol in the near-critical n-hexane fluid.

  19. Quantification of 16 polycyclic aromatic hydrocarbons in cigarette smoke condensate using stable isotope dilution liquid chromatography with atmospheric-pressure photoionization tandem mass spectrometry.

    Science.gov (United States)

    Zhang, Xiaotao; Hou, Hongwei; Chen, Huan; Liu, Yong; Wang, An; Hu, Qingyuan

    2015-09-17

    A stable isotope dilution liquid chromatography with tandem mass spectrometry method for the analysis of 16 polycyclic aromatic hydrocarbons in cigarette smoke condensate was developed and validated. Compared with previously reported methods, this method has lower limits of detection (0.04-1.35 ng/cig). Additionally, the proposed method saves time, reduces the number of separation steps, and reduces the quantity of solvent needed. The new method was applied to evaluate polycyclic aromatic hydrocarbon content in 213 commercially available cigarettes in China, under the International Standardization Organization smoking regime and the Health Canadian intense smoking regime. The results showed that the total polycyclic aromatic hydrocarbon content was more than two times higher in samples from the Health Canadian intense smoking regime than in samples from the International Standardization Organization smoking regime (1189.23 vs. 2859.50 ng/cig, ppolycyclic aromatic hydrocarbons (and total polycyclic aromatic hydrocarbons) increased with labeled tar content in both of the tested smoking regimes. There was a positive correlation between total polycyclic aromatic hydrocarbons under the International Standardization Organization smoking regime with that under the Health Canadian intense smoking regime. The proposed liquid chromatography with tandem mass spectrometry method is satisfactory for the rapid, sensitive, and accurately quantitative evaluation of polycyclic aromatic hydrocarbon content in cigarette smoke condensate, and it can be applied to assess potential health risks from smoking. This article is protected by copyright. All rights reserved.

  20. Solvent-Free Synthesis of New Coumarins

    Directory of Open Access Journals (Sweden)

    Redah I. Al-Bayati

    2012-01-01

    Full Text Available A solvent-free synthesis of five series of coumarin derivatives using microwave assistant is presented herein. The synthesized compounds are fully characterized by UV-VIS, FT-IR, and NMR spectroscopy.

  1. "Solvent Effects" in 1H NMR Spectroscopy.

    Science.gov (United States)

    Cavaleiro, Jose A. S.

    1987-01-01

    Describes a simple undergraduate experiment in chemistry dealing with the "solvent effects" in nuclear magnetic resonance (NMR) spectroscopy. Stresses the importance of having students learn NMR spectroscopy as a tool in analytical chemistry. (TW)

  2. Solvent Extraction Developments in Southern Africa

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The largest solvent-extraction plant in the world at the time, the Nchanga Copper Operation, was in Zambia. The first commercial process using solvent extraction for the refining of the platinum-group metals was in South Africa. More recently, the Southern African region has seen the implementation of solvent extraction for other base metals, precious metals, and specialty metals. These include the world firsts of primary production of zinc at Skorpion Zinc in Namibia and the large-scale refining of gold by Harmony Gold in South Africa. Several other flowsheets that use solvent-extraction technology are currently under commissioning, development, or feasibility study for implementation in this part of the world, including those for the recovery of copper, cobalt, nickel, tantalum, and niobium.

  3. Water as a Solvent for Life

    Science.gov (United States)

    Pohorille, Andrew; Pratt, Lawrence R.

    2015-01-01

    "Follow the water" is our basic strategy in searching for life in the universe. The universality of water as the solvent for living systems is usually justified by arguing that water supports the rich organic chemistry that seeds life, but alternative chemistries are possible in other organic solvents. Here, other, essential criteria for life that have not been sufficiently considered so far, will be discussed.

  4. Biofiltration of solvent vapors from air

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Young-sook.

    1993-01-01

    For various industrial solvent vapors, biofiltration promises to offer a cost-effective emission control technology. Exploiting the full potential of this technology will help attain the goals of the Clean Air Act Amendments of 1990. Concentrating on large volumes of volatile industrial solvents, stable multicomponent microbial enrichments capable of growing a mineral medium with solvent vapors as their only source of carbon and energy were obtained from soil and sewage sludge. These consortia were immobilized on an optimized porous solid support (ground peat moss and perlite). The biofilter material was packed in glass columns connected to an array of pumps and flow meters that allowed the independent variation of superficial velocity and solvent vapor concentrations. In various experiments, single solvents, such as methanol, butanol, acetonitrile, hexane and nitrobenzene, and solvent mixtures, such as benzene-toluene-xylene (BTX) and chlorobenzene-o-dichlorobenzene (CB/DCB) were biofiltered with rates ranging from 15 to334 g solvent removed per m[sup 3] filter volume /h. Pressure drops were low to moderate (0-10 mmHg/m) and with periodic replacement of moisture, the biofiltration activity could be maintained for a period of several months. The experimental data on methanol biofiltration were subjected to mathematical analysis and modeling by the group of Dr. Baltzis at NJIT for a better understanding and a possible scale up of solvent vapor biofilters. In the case of chlorobenzenes and nitrobenzene, the biofilter columns had to be operated with water recirculation in a trickling filter mode. To prevent inactivation of the trickling filter by acidity during CB/DCB removal, pH control was necessary, and the removal rate of CB/DCB was strongly influenced by the flow rate of the recyling water. Nitrobenzene removal in a trickling filter did not require pH control, since the nitro group was reduced and volatilized as ammonia.

  5. Competitive solvent-molecule interactions govern primary processes of diphenylcarbene in solvent mixtures

    Science.gov (United States)

    Knorr, Johannes; Sokkar, Pandian; Schott, Sebastian; Costa, Paolo; Thiel, Walter; Sander, Wolfram; Sanchez-Garcia, Elsa; Nuernberger, Patrick

    2016-10-01

    Photochemical reactions in solution often proceed via competing reaction pathways comprising intermediates that capture a solvent molecule. A disclosure of the underlying reaction mechanisms is challenging due to the rapid nature of these processes and the intricate identification of how many solvent molecules are involved. Here combining broadband femtosecond transient absorption and quantum mechanics/molecular mechanics simulations, we show for one of the most reactive species, diphenylcarbene, that the decision-maker is not the nearest solvent molecule but its neighbour. The hydrogen bonding dynamics determine which reaction channels are accessible in binary solvent mixtures at room temperature. In-depth analysis of the amount of nascent intermediates corroborates the importance of a hydrogen-bonded complex with a protic solvent molecule, in striking analogy to complexes found at cryogenic temperatures. Our results show that adjacent solvent molecules take the role of key abettors rather than bystanders for the fate of the reactive intermediate.

  6. Solvent dependent photophysical properties of dimethoxy curcumin

    Science.gov (United States)

    Barik, Atanu; Indira Priyadarsini, K.

    2013-03-01

    Dimethoxy curcumin (DMC) is a methylated derivative of curcumin. In order to know the effect of ring substitution on photophysical properties of curcumin, steady state absorption and fluorescence spectra of DMC were recorded in organic solvents with different polarity and compared with those of curcumin. The absorption and fluorescence spectra of DMC, like curcumin, are strongly dependent on solvent polarity and the maxima of DMC showed red shift with increase in solvent polarity function (Δf), but the above effect is prominently observed in case of fluorescence maxima. From the dependence of Stokes' shift on solvent polarity function the difference between the excited state and ground state dipole moment was estimated as 4.9 D. Fluorescence quantum yield (ϕf) and fluorescence lifetime (τf) of DMC were also measured in different solvents at room temperature. The results indicated that with increasing solvent polarity, ϕf increased linearly, which has been accounted for the decrease in non-radiative rate by intersystem crossing (ISC) processes.

  7. Method for producing diene hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Tsaylingol' d, A.L.; Abayev, G.N.; Mikhaylov, R.K.; Stepanov, G.A.; Troitskiy, A.P.

    1980-04-28

    A method is claimed for producing diene hydrocarbons by oxidational dehydration of paraffin or olefin hydrocarbons in a fluidized bed of a concentrate with circulation of the latter between the zones of the reaction of regeneration with the help of circulation stand pipes. To increase the efectiveness of the process, it is proposed to circulate the concentrate between the zones of reaction and regeneration, sequentially disposed in a common apparatus with a difference in the concentration of the concentrate in the circulation stand pipes disposed in the same apparatus and the zone of the reaction equal to 20-700 kg/m/sup 3/. For example, the process of oxidational dehydration of butane through the proposed system is conducted in an apparatus with a diameter of 1,000 mm, a circulation stand pipe diameter of 500 mm, a linear gas speed in the reaction zone of 0.6 m/s, and in the circulation stand pipe of 0.15 m/s. The concentration of the concentrate in the dehydration zone is 640 kg/m/sup 3/ and in the stand pipe, 970 kg/m/sup 3/. The volumetric ratio of the n-C/sub 4/H/sub 10/:air, air:vapor vapor in the form of a condensate is 1:7.2:4.5:5.5. The output of the butadiene is: in the passed butane, 32.9% and in the broken down butane, 52.5%. The butane conversion is 62.6%. The losses of the concentrate with the contact gas and with the regeneration gases is 1/3 as much for the supplied butane, than in a known method. The method makes it possible to reduce the air expenditure by 60%, to reduce the concentrate losses by 2-3 times and to simplify the industrial system.

  8. Caustic-Side Solvent Extraction: Chemical and Physical Properties of the Optimized Solvent

    Energy Technology Data Exchange (ETDEWEB)

    Delmau, L.H.

    2002-10-08

    This work was undertaken to optimize the solvent used in the Caustic Side Solvent Extraction (CSSX) process and to measure key chemical and physical properties related to its performance in the removal of cesium from the alkaline high-level salt waste stored in tanks at the Savannah River Site. The need to adjust the solvent composition arose from the prior discovery that the previous baseline solvent was supersaturated with respect to the calixarene extractant. The following solvent-component concentrations in Isopar{reg_sign} L diluent are recommended: 0.007 M calix[4]arene-bis(tert-octylbenzo-crown-6) (BOBCalixC6) extractant, 0.75 M 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB) phase modifier, and 0.003 M tri-n-octylamine (TOA) stripping aid. Criteria for this selection included BOBCalixC6 solubility, batch cesium distribution ratios (D{sub Cs}), calculated flowsheet robustness, third-phase formation, coalescence rate (dispersion numbers), and solvent density. Although minor compromises within acceptable limits were made in flowsheet robustness and solvent density, significant benefits were gained in lower risk of third-phase formation and lower solvent cost. Data are also reported for the optimized solvent regarding the temperature dependence of D{sub Cs} in extraction, scrubbing, and stripping (ESS); ESS performance on recycle; partitioning of BOBCalixC6, Cs-7SB, and TOA to aqueous process solutions; partitioning of organic anions; distribution of metals; solvent phase separation at low temperatures; solvent stability to elevated temperatures; and solvent density and viscosity. Overall, the technical risk of the CSSX process has been reduced by resolving previously identified issues and raising no new issues.

  9. Computer-aided tool for solvent selection in pharmaceutical processes: Solvent swap

    DEFF Research Database (Denmark)

    Papadakis, Emmanouil; K. Tula, Anjan; Gernaey, Krist V.

    In the pharmaceutical processes, solvents have a multipurpose role since different solvents can be used in different stages (such as chemical reactions, separations and purification) in the multistage active pharmaceutical ingredients (APIs) production process. The solvent swap and selection task......-aided framework with the objective to assist the pharmaceutical industry in gaining better process understanding. A software interface to improve the usability of the tool has been created also....

  10. Influence of solvent polarity on preferential solvation of molecular recognition probes in solvent mixtures.

    Science.gov (United States)

    Amenta, Valeria; Cook, Joanne L; Hunter, Christopher A; Low, Caroline M R; Vinter, Jeremy G

    2012-12-13

    The association constants for formation of 1:1 complexes between a H-bond acceptor, tri-n-butylphosphine oxide, and a H-bond donor, 4-phenylazophenol, have been measured in a range of different solvent mixtures. Binary mixtures of n-octane and a more polar solvent (ether, ester, ketone, nitrile, sulfoxide, tertiary amide, and halogenated and aromatic solvents) have been investigated. Similar behavior was observed in all cases. When the concentration of the more polar solvent is low, the association constant is identical to that observed in pure n-octane. Once a threshold concentration of the more polar solvent in reached, the logarithm of the association constant decreases in direct proportion to the logarithm of the concentration of the more polar solvent. This indicates that one of the two solutes is preferentially solvated by the more polar solvent, and it is competition with this solvation equilibrium that determines the observed association constant. The concentration of the more polar solvent at which the onset of preferential solvation takes place depends on solvent polarity: 700 mM for toluene, 60 mM for 1,1,2,2-tetrachloroethane, 20 mM for the ether, ester, ketone, and nitrile, 0.2 mM for the tertiary amide, and 0.1 mM for the sulfoxide solvents. The results can be explained by a simple model that considers only pairwise interactions between specific sites on the surfaces of the solutes and solvents, which implies that the bulk properties of the solvent have little impact on solvation thermodynamics.

  11. Innovative eco-friendly bio- solvent for combating sea surface and sedimented oil pollution

    Science.gov (United States)

    Theodorou, Paraskevas

    2017-04-01

    The combating of oil spill at sea surface by chemical dispersants accelerates the evaporation and disperse the oil into the water column, where it is broken down by natural processes and/or is sedimented at the sea bottom, especially at near coastal shallow areas, ports and marinas. The usual methodology for cleaning the sedimented oil from the sea bottom is mainly carried out via excavation and dumping of the polluted sediment into deeper sea areas, where the contamination is transferred from one area to another. The eco-friendly bio-solvent MSL Aqua 250 is an innovative new solution based mainly on natural constituents. The action mechanism and the effectiveness of this eco-friendly solvent is based on the high surface tension process. Organic compounds, including hydrocarbons upon coming in contact with MSL Aqua 250 solvent generate a significant surface tension reaction, which is able to alter the organic compounds to liquid form and then to drastically evaporate it. The use of MSL Aqua 250 solvent, both at sea surface and at the bottom, has the following advantages compared to the dispersants: • Efficient solution without transferring the pollution from sea surface to the water column and to the bottom or disturbing the Aquatic Eco System. • Non-Toxic. • Environmentally friendly with a restoration of marine life in the Eco System. • Cost effective. The MSL Aqua 250 solvent has been tested in cooperation with the Cyprus Department of Fisheries and Marine Research and the Technological University of Cyprus and used during the years 2015 and 2016 in marinas and fishing shelters in Cyprus faced oil pollution, with high concentration in the sea water and at the sea bottom of chemical parameters (BOD5, COD, FOG, TKN, TP, TPH), with excellent results.

  12. Hydrolysis of fluorotelomer compounds leading to fluorotelomer alcohol production during solvent extractions of soils.

    Science.gov (United States)

    Dasu, Kavitha; Royer, Laurel A; Liu, Jinxia; Lee, Linda S

    2010-11-01

    The experimental approaches used in assessing the biodegradability of fluorotelomer-based surfactants and polymers have been under increasing scrutiny. These substances consist of an aliphatic or aromatic backbone linked to perfluoroethyl moieties by ester, ether or urethane linkages. These linkages when broken yield fluorotelomer alcohols (FTOHs), which are known to biotransform to a suite of polyfluorinated metabolites including perfluorinated carboxylic acids. Quantifying FTOH levels with minimal experimental artifacts is imperative in properly assessing the biotransformation potential and half-lives of fluorotelomer-based materials. We examined the potential for solvent-enhanced ester hydrolysis of fluorotelomer compounds with different hydrocarbon backbones including a monoester stearate (FTS), a citrate tri-ester (TBC), an acrylate (FTA), and a 2,4-toluenediamine urethane (FTU) in acetonitrile, methyl-t-butyl ether (MTBE), and ethyl acetate with live, autoclaved, 60Co-γ-irradiated, and heat-treated (400°C) soils. Substantial hydrolysis only occurred with FTS in live and γ-irradiated soils for which microbial enzymes are expected to be active, but not in autoclaved soils where enzymes are deactivated. Acetonitrile and methanol (solvents with higher dielectric constants) enhanced hydrolysis by an order of magnitude compared to less polar solvents such as MTBE and ethyl acetate. For example, in a 24-h extraction with acetonitrile of FTS-amended soil, >5wt.% FTOH was produced compared to ethyl acetate or MTBE. FTA hydrolysis was <0.7 wt.% after a 15-h extraction period and was not solvent dependent. No statistically significant solvent-enhanced hydrolysis was observed for TBC, FTA or FTU.

  13. A modified microbial adhesion to hydrocarbons assay to account for the presence of hydrocarbon droplets.

    Science.gov (United States)

    Zoueki, Caroline Warne; Tufenkji, Nathalie; Ghoshal, Subhasis

    2010-04-15

    The microbial adhesion to hydrocarbons (MATH) assay has been used widely to characterize microbial cell hydrophobicity and/or the extent of cell adhesion to hydrophobic liquids. The classical MATH assay involves spectrophotometric absorbance measurements of the initial and final cell concentrations in an aqueous cell suspension that has been contacted with a hydrocarbon liquid. In this study, microscopic examination of the aqueous cell suspension after contact with hexadecane or a hexadecane/toluene mixture revealed the presence of hydrocarbon droplets. The hydrocarbon droplets contributed to the absorbance values during spectrophotometric measurements and caused erroneous estimates of cell concentrations and extents of microbial adhesion. A modified MATH assay that avoids such artefacts is proposed here. In this modified assay, microscopic examination of the aqueous suspension and direct cell counts provides cell concentrations that are free of interference from hydrocarbon droplets. The presence of hydrocarbon droplets was noted in MATH assays performed with three bacterial strains, and two different hydrocarbons, at ionic strengths of 0.2 mM and 20 mM and pH 6. In these experiments, the formation of quasi-stable hydrocarbon droplets cannot be attributed to the presence of biosurfactants, or stabilization by biocolloids. The presence of surface potential at the hydrocarbon-water interface that was characterized by electrophoretic mobility of up to -1 and -2 microm cm/Vs, likely caused the formation of the quasi-stable hydrocarbon droplets that provided erroneous results using the classical MATH assay.

  14. CHEMICAL STABILITY OF POLYPHENYLENE SULFIDE IN THE NEXT GENERATION SOLVENT FOR CAUSTIC-SIDE SOLVENT EXTRACTION

    Energy Technology Data Exchange (ETDEWEB)

    Fondeur, F.; Fink, S.

    2011-12-08

    The Office of Waste Processing, within the Office of Technology Innovation and Development, is funding the development of an enhanced solvent for deployment at the Savannah River Site for removal of cesium from High Level Waste. For simplicity, this solvent is referred to as the Next Generation Solvent (NGS). The technical effort is collaboration between Oak Ridge National Laboratory (ORNL), Savannah River National Laboratory (SRNL), and Argonne National Laboratory. The initial deployment target envisioned for the technology was within the Modular Caustic-Side Solvent Extraction Unit (MCU). Deployment of a new chemical within an existing facility requires verification that the chemical components are compatible with the installed equipment. In the instance of a new organic solvent, the primary focus is on compatibility of the solvent with polyphenylene sulfide (PPS), the polymer used in the coalescers within MCU. This report provides the data from exposing PPS polymer to NGS. The test was conducted over a three month period. PPS is remarkably stable in the presence of the next generation solvent. Testing showed no indication of swelling or significant leaching. Preferential sorption of the Modifier on PPS was observed but the same behavior occurs with the baseline solvent. Therefore, PPS coalescers exposed to the NGS are expected to perform comparably to those in contact with the baseline solvent.

  15. The use of environmentally sustainable bio-derived solvents in solvent extraction applications-A review

    Institute of Scientific and Technical Information of China (English)

    Zheng Li; Kathryn H. Smith; Geoffrey W. Stevens

    2016-01-01

    Replacement of volatile organic compounds (VOCs) by greener or more environmental y sustainable solvents is becoming increasingly important due to the increasing health and environmental concerns as wel as economic pressures associated with VOCs. Solvents that are derived from biomass, namely bio-derived solvents, are a type of green solvent that have attracted intensive investigations in recent years because of their advantages over con-ventional VOCs, such as low toxicity, biodegradability and renewability. This review aims to summarize the use of bio-derived solvents in solvent extraction applications, with special emphasis given to utilization of biodiesels and terpenes. Compared with the conventional VOCs, the overall performance of these bio-derived solvents is comparable in terms of extraction yields and selectivity for natural product extraction and no difference was found for metal extraction. To date most researchers have focused on laboratory scale thermodynamics studies. Future work is required to develop and test new bio-derived solvents and understand the kinetic performance as well as solvent extraction pilot plant studies.

  16. CHEMICAL STABILITY OF POLYPHENYLENE SULFIDE IN THE NEXT GENERATION SOLVENT FOR CAUSTIC-SIDE SOLVENT EXTRACTION

    Energy Technology Data Exchange (ETDEWEB)

    Fondeur, F.; Fink, S.

    2011-12-08

    The Office of Waste Processing, within the Office of Technology Innovation and Development, is funding the development of an enhanced solvent for deployment at the Savannah River Site for removal of cesium from High Level Waste. For simplicity, this solvent is referred to as the Next Generation Solvent (NGS). The technical effort is collaboration between Oak Ridge National Laboratory (ORNL), Savannah River National Laboratory (SRNL), and Argonne National Laboratory. The initial deployment target envisioned for the technology was within the Modular Caustic-Side Solvent Extraction Unit (MCU). Deployment of a new chemical within an existing facility requires verification that the chemical components are compatible with the installed equipment. In the instance of a new organic solvent, the primary focus is on compatibility of the solvent with polyphenylene sulfide (PPS), the polymer used in the coalescers within MCU. This report provides the data from exposing PPS polymer to NGS. The test was conducted over a three month period. PPS is remarkably stable in the presence of the next generation solvent. Testing showed no indication of swelling or significant leaching. Preferential sorption of the Modifier on PPS was observed but the same behavior occurs with the baseline solvent. Therefore, PPS coalescers exposed to the NGS are expected to perform comparably to those in contact with the baseline solvent.

  17. Influence of Energy on Solvent Diffusion in Polymer/Solvent Systems

    Institute of Scientific and Technical Information of China (English)

    HUHuijun; JIANGWenhua; 等

    2002-01-01

    The Vrentas-Duda free-volume theory has been extensively used to correlate or predict the solvent diffusion coefficient of a polymer/solvent system.The energy term in the free volume diffusion equation is difficult to estimate,so the energy term was usually neglected in previous predictive versions of the free volume diffusion coefficient equation.Recent studies show that the energy effect is very important even above the glass transition temperature of the system. In this paper, a new evaluation method of the energy term is proposed,that is the diffusion energy at different solvent concentrations is assumed to be a linear function of the solvent diffusion energy in pure solvents and that in polymers under the condition that the solvent in infinite dilution.By taking consideration of the influence of energy on the solvent diffustion,the prediction of solvent diffusion coefficient was preformed for three polymer/solvent systems over a wide range of concentrations and temperatures.The results show an improvement on the predictive capability of the free volume diffusion theory.

  18. Hydrocarbon degradation abilities of psychrotolerant Bacillus strains

    Directory of Open Access Journals (Sweden)

    Fulya Kolsal

    2017-06-01

    Full Text Available Biodegradation requires identification of hydrocarbon degrading microbes and the investigation of psychrotolerant hydrocarbon degrading microbes is essential for successful biodegradation in cold seawater. In the present study, a total of 597 Bacillus isolates were screened to select psychrotolerant strains and 134 isolates were established as psychrotolerant on the basis of their ability to grow at 7 °C. Hydrocarbon degradation capacities of these 134 psychrotolerant isolate were initially investigated on agar medium containing different hydrocarbons (naphthalene, n-hexadecane, mineral oil and 47 positive isolates were grown in broth medium containing hydrocarbons at 20 °C under static culture. Bacterial growth was estimated in terms of viable cell count (cfu ml–1. Isolates showing the best growth in static culture were further grown in presence of crude oil under shaking culture and viable cell count was observed between 8.3 × 105–7.4 × 108 cfu ml–1. In the final step, polycyclic aromatic hydrocarbon (PAH (chrysene and naphthalene degradation yield of two most potent isolates was determined by GC-MS along with the measurement of pH, biomass and emulsification activities. Results showed that isolates Ege B.6.2i and Ege B.1.4Ka have shown 60% and 36% chrysene degradation yield, respectively, while 33% and 55% naphthalene degradation yield, respectively, with emulsification activities ranges between 33–50%. These isolates can be used to remove hydrocarbon contamination from different environments, particularly in cold regions.

  19. Stability of the Caustic-Side Solvent Extraction (CSSX) Process Solvent: Effect of High Nitrite on Solvent Nitration

    Energy Technology Data Exchange (ETDEWEB)

    Bonnesen, P.V.

    2002-06-26

    The purpose of this investigation was to determine whether nitrated organic compounds could be formed during operation of the Caustic-Side Solvent Extraction (CSSX) process, and whether such compounds would present a safety concern. The CSSX process was developed to remove cesium from alkaline high-level salt waste stored at the US Department of Energy Savannah River Site (SRS). The solvent is composed of the cesium extractant calix[4]arene-bis-(4-tert-octylbenzo-crown-6) (BOBCalixC6), a fluorinated alcohol phase modifier, tri-n-octylamine (TOA), and an isoparaffinic diluent (Iospar{reg_sign}). During the CSSX process, the solvent is expected to be exposed to high concentrations of nitrate and nitrite dissolved in the alkaline waste feed. The solvent will also be exposed to dilute (50 mM) nitric acid solutions containing low concentrations of nitrite during scrubbing, followed by stripping with 1 mM nitric acid. The solvent is expected to last for one year of plant operation, and the temperatures the solvent may experience during the process could range from as low as 15 C to as high as 35 C. Excursions from standard process conditions could result in the solvent experiencing higher temperatures, as well as concentrations of nitrate, nitrite, and most importantly nitric acid, that exceed normal operating conditions. Accordingly, conditions may exist where nitration reactions involving the solvent components, possibly leading to other chemical reactions stemming from nitration reactions, could occur. To model such nitration reactions, the solvent was exposed to the types of nitrate- and nitrite-containing solutions that might be expected to be encountered during the process (even under off-normal conditions), as a function of time, temperature, and concentration of nitrate, nitrite, and nitric acid. The experiments conducted as part of this report were designed to examine the more specific effect that high nitrite concentrations could have on forming nitrated

  20. Waste Plastic Converting into Hydrocarbon Fuel Materials

    Energy Technology Data Exchange (ETDEWEB)

    Sarker, Moinuddin; Mamunor Rashid, Mohammad; Molla, Mohammad

    2010-09-15

    The increased demand and high prices for energy sources are driving efforts to convert organic compounds into useful hydrocarbon fuels. Although much of this work has focused on biomass, there are strong benefits to deriving fuels from waste plastic material. Natural State Research Inc. (NSR) has invented a simple and economically viable process to decompose the hydrocarbon polymers of waste plastic into the shorter chain hydrocarbon of liquid fuel (patent pending). The method and principle of the production / process will be discussed. Initial tests with several widely used polymers indicate a high potential for commercialization.

  1. Using supercritical fluids to refine hydrocarbons

    Science.gov (United States)

    Yarbro, Stephen Lee

    2015-06-09

    A system and method for reactively refining hydrocarbons, such as heavy oils with API gravities of less than 20 degrees and bitumen-like hydrocarbons with viscosities greater than 1000 cp at standard temperature and pressure, using a selected fluid at supercritical conditions. A reaction portion of the system and method delivers lightweight, volatile hydrocarbons to an associated contacting unit which operates in mixed subcritical/supercritical or supercritical modes. Using thermal diffusion, multiphase contact, or a momentum generating pressure gradient, the contacting unit separates the reaction products into portions that are viable for use or sale without further conventional refining and hydro-processing techniques.

  2. Emulsification of hydrocarbons by subsurface bacteria

    Science.gov (United States)

    Francy, D.S.; Thomas, J.M.; Raymond, R.L.; Ward, C.H.

    1991-01-01

    Biosurfactants have potential for use in enhancement of in situ biorestoration by increasing the bioavailability of contaminants. Microorganisms isolated from biostimulated, contaminated and uncontaminated zones at the site of an aviation fuel spill and hydrocarbon-degrading microorganisms isolated from sites contaminated with unleaded gasoline were examined for their abilities to emulsify petroleum hydrocarbons. Emulsifying ability was quantified by a method involving agitation and visual inspection. Biostimulated-zone microbes and hydrocarbon-degrading microorganisms were the best emulsifiers as compared to contaminated and uncontaminated zone microbes. Biostimulation (nutrient and oxygen addition) may have been the dominant factor which selected for and encouraged growth of emulsifiers; exposure to hydrocarbon was also important. Biostimulated microorganisms were better emulsifiers of aviation fuel (the contaminant hydrocarbon) than of heavier hydrocarbon to which they were not previously exposed. By measuring surface tension changes of culture broths, 11 out of 41 emulsifiers tested were identified as possible biosurfactant producers and two isolates produced large surface tension reductions indicating the high probability of biosurfactant production.Biosurfactants have potential for use in enhancement of in situ biorestoration by increasing the bioavailability of contaminants. Microorganisms isolated from biostimulated, contaminated and uncontaminated zones at the site of an aviation fuel spill and hydrocarbon-degrading microorganisms isolated from sites contaminated with unleaded gasoline were examined for their abilities to emulsify petroleum hydrocarbons. Emulsifying ability was quantified by a method involving agitation and visual inspection. Biostimulated-zone microbes and hydrocarbon-degrading microorganisms were the best emulsifiers as compared to contaminated and uncontaminated zone microbes. Biostimulation (nutrient and oxygen addition) may have been

  3. Novel, benign, solid catalysts for the oxidation of hydrocarbons.

    Science.gov (United States)

    Ratnasamy, Paul; Raja, Robert; Srinivas, Darbha

    2005-04-15

    The catalytic properties of two classes of solid catalysts for the oxidation of hydrocarbons in the liquid phase are discussed: (i) microporous solids, encapsulating transition metal complexes in their cavities and (ii) titanosilicate molecular sieves. Copper acetate dimers encapsulated in molecular sieves Y, MCM-22 and VPI-5 use dioxygen to regioselectively ortho-hydroxylate L-tyrosine to L-dopa, phenol to catechol and cresols to the corresponding o-dihydroxy and o-quinone compounds. Monomeric copper phthalocyanine and salen complexes entrapped in zeolite-Y oxidize methane to methanol, toluene to cresols, naphthalene to naphthols, xylene to xylenols and phenol to diphenols. Trimeric mu3-oxo-bridged Co/Mn cluster complexes, encapsulated inside Y-zeolite, oxidize para-xylene, almost quantitatively, to terephthalic acid. In almost all cases, the intrinsic catalytic activity (turnover frequency) of the metal complex is enhanced very significantly, upon encapsulation in the porous solids. Spectroscopic and electrochemical studies suggest that the geometric distortions of the complex on encapsulation change the electron density at the metal ion site and its redox behaviour, thereby influencing its catalytic activity and selectivity in oxidation reactions. Titanosilicate molecular sieves can oxidize hydrocarbons using dioxygen when loaded with transition metals like Pd, Au or Ag. The structure of surface Ti ions and the type of oxo-Ti species generated on contact with oxidants depend on several factors including the method of zeolite synthesis, zeolite structure, solvent, temperature and oxidant. Although, similar oxo-Ti species are present on all the titanosilicates, their relative concentrations vary among different structures and determine the product selectivity.

  4. C 2-C 10 nonmethane hydrocarbons measured in Dallas, USA—Seasonal trends and diurnal characteristics

    Science.gov (United States)

    Qin, Y.; Walk, T.; Gary, R.; Yao, X.; Elles, S.

    Nonmethane hydrocarbons (NMHCs) are important precursors of ozone and other photo oxidants. We presented continuous hourly average concentrations of 45 C 2-C 10 NMHCs measured in urban area of Dallas, USA from 1996 to 2004. Most of the selected compounds are good variables with less noise. The top 10 species with high ozone-generating potential were identified according to their concentrations and reactivities. The ambient concentrations of abundant anthropogenic emission hydrocarbons measured in Dallas were about 2-4 times of the background values measured in the remote areas with adjacent latitude. The time series for anthropogenic emission hydrocarbons showed an obvious seasonal cycle with relatively high concentration in winter and low concentration in summer. The sinusoidal function with a linearly decreasing factor could well fit the time series of NMHCs. The phase of seasonal cycle for the aromatic hydrocarbons of toluene, m/ p xylene and o-xylene that might come from both vehicle emission and solvent utilities evaporation was about 1 month earlier than that for alkanes and alkenes that mainly came from vehicle emission. Ambient NMHCs in Dallas decreased with a stable rate during 1996-2004. For most of compounds with high ozone-generating potential, the rate of ambient concentration decrease was higher or much higher than the rate of volatile organic compounds (VOCs) source emission reduction estimated by EPA's National Emission Inventory. On weekdays, the morning hydrocarbon concentration peak was coincident with morning traffic rush time in Dallas. Another concentration peak was delayed to afternoon traffic rush time. The characteristics of VOCs sources, photochemical removal processes and atmospheric dilution could be interpreted by the diurnal variations of benzene/ethylbenzene (B/E), toluene/ethylbenzene (T/E) and xylene/ethylbenzene (X/E). The ratio of VOC/NO x measured in Dallas was substantially smaller than that calculated for USA cities. Ozone

  5. Lipase catalyzed esterification of glycidol in nonaqueous solvents: solvent effects on enzymatic activity.

    Science.gov (United States)

    Martins, J F; de Sampaio, T C; de Carvalho, I B; Barreiros, S

    1994-06-05

    We studied the effect of organic solvents on the kinetics of porcine pancreatic lipase (pp) for the resolution of racemic glycidol through esterification with butyric acid. We quantified ppl hydration by measuring water sorption isotherms for the enzyme in the solvents/mixtures tested. The determination of initial rates as a function of enzyme hydration revealed that the enzyme exhibits maximum apparent activity in the solvents/mixtures at the same water content (9% to 11% w/w) within the associated experimental error. The maximum initial rates are different in all the media and correlate well with the logarithm of the molar solubility of water in the media, higher initial rates being observed in the solvents/mixtures with lower water solubilities. The data for the mixtures indicate that ppl apparent activity responds to bulk property of the solvent. Measurements of enzyme particle sizes in five of the solvents, as function of enzyme hydration, revealed that mean particle sizes increased with enzyme hydration in all the solvents, differences between solvents being more pronounced at enzyme hydration levels close to 10%. At this hydration level, solvents having a higher water content lead to lower reaction rates; these are the solvents where the mean enzyme particle sizes are greater. Calculation of the observable modulus indicates there are no internal diffusion limitations. The observed correlation between changes in initial rates and changes in external surface area of the enzyme particles suggests that interfacial activation of ppl is only effective at the external surface of the particles. Data obtained for the mixtures indicate that ppl enantioselectivity depends on specific solvent-enzyme interactions. We make reference to ppl hydration and activity in supercritical carbon dioxide.

  6. 40 CFR 86.317-79 - Hydrocarbon analyzer specifications.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Hydrocarbon analyzer specifications....317-79 Hydrocarbon analyzer specifications. (a) Hydrocarbon measurements are to be made with a heated... measures hydrocarbon emissions on a dry basis is permitted for gasoline-fueled testing; Provided,...

  7. 40 CFR 92.119 - Hydrocarbon analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Hydrocarbon analyzer calibration. 92... Hydrocarbon analyzer calibration. The HFID hydrocarbon analyzer shall receive the following initial and... into service and at least annually thereafter, the HFID hydrocarbon analyzer shall be adjusted...

  8. 40 CFR 86.1321-94 - Hydrocarbon analyzer calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Hydrocarbon analyzer calibration. 86... Procedures § 86.1321-94 Hydrocarbon analyzer calibration. The FID hydrocarbon analyzer shall receive the... into service and at least annually thereafter, the FID hydrocarbon analyzer shall be adjusted...

  9. 21 CFR 178.3530 - Isoparaffinic petroleum hydrocarbons, synthetic.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Isoparaffinic petroleum hydrocarbons, synthetic... hydrocarbons, synthetic. Isoparaffinic petroleum hydrocarbons, synthetic, may be safely used in the production... isoparaffinic petroleum hydrocarbons, produced by synthesis from petroleum gases consist of a mixture of...

  10. 21 CFR 172.882 - Synthetic isoparaffinic petroleum hydrocarbons.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Synthetic isoparaffinic petroleum hydrocarbons. 172... hydrocarbons. Synthetic isoparaffinic petroleum hydrocarbons may be safely used in food, in accordance with the... liquid hydrocarbons meeting the following specifications: Boiling point 93-260 °C as determined by...

  11. Phase equilibria study of the binary systems (N-hexylisoquinolinium thiocyanate ionic liquid + organic solvent or water).

    Science.gov (United States)

    Królikowska, Marta; Karpińska, Monika; Zawadzki, Maciej

    2012-04-12

    Liquid-liquid phase equilibria (LLE) of binary mixtures containing a room-temperature ionic liquid N-hexylisoquinolinium thiocyanate, [HiQuin][SCN] with an aliphatic hydrocarbon (n-hexane, n-heptane), aromatic hydrocarbon (benzene, toluene, ethylbenzene, n-propylbenzene), cyclohexane, thiophene, water, and 1-alcohol (1-ethanol, 1-butanol, 1-hexanol, 1-octanol, 1-decanol) have been determined using a dynamic method from room temperature to the boiling-point of the solvent at ambient pressure. N-hexylisoquinolinium thiocyanate, [HiQuin][SCN] has been synthesized from N-hexyl-isoquinolinium bromide as a substrate. Specific basic characterization of the new compound including NMR spectra, elementary analysis, and water content have been done. The density and viscosity of pure ionic liquid were determined over a wide temperature range from 298.15 to 348.15 K. The mutual immiscibility with an upper critical solution temperature (UCST) for the binary systems {IL + aliphatic hydrocarbon, cyclohexane, or water} was detected. In the systems of {IL + aromatic hydrocarbon or thiophene} an immiscibility gap with a lower critical solution temperature (LCST) was observed. Complete miscibility in the liquid phase, over a whole range of ionic liquid mole fraction, was observed for the binary mixtures containing IL and an 1-alcohol. For the tested binary systems with immiscibility gap {IL + aliphatic hydrocarbon, aromatic hydrocarbon, cyclohexane, thiophene, or water}, the parameters of the LLE correlation have been derived using the NRTL equation. The basic thermal properties of the pure IL, that is, the glass-transition temperature as well as the heat capacity at the glass-transition temperature, have been measured using a differential scanning microcalorimetry technique (DSC). Decomposition of the IL was detected by simultaneous thermogravimetric/differential thermal analysis (TG/DTA) experiments.

  12. New Polymeric Membranes for Organic Solvent Nanofiltration

    KAUST Repository

    Aburabie, Jamaliah

    2017-05-01

    The focus of this dissertation was the development, synthesis and modification of polymers for the preparation of membranes for organic solvent nanofiltration. High chemical stability in a wide range of solvents was a key requirement. Membranes prepared from synthesized polymers as well as from commercial polymers were designed and chemically modified to reach OSN requirements. A solvent stable thin-film composite (TFC) membrane is reported, which is fabricated on crosslinked polythiosemicarbazide (PTSC) as substrate. The membranes exhibited high fluxes towards solvents like THF, DMF and DMSO ranging around 20 L/m2 h at 5 bar with a MWCO of around 1000 g/mol. Ultrafiltration PTSC membranes were prepared by non-solvent induced phase separation and crosslinked with GPTMS. The crosslinking reaction was responsible for the formation of an inorganic-type-network that tuned the membrane pore size. The crosslinked membranes acquired high solvent stability in DMSO, DMF and THF with a MWCO above 1300 g/mol. Reaction Induced Phase Separation (RIPS) was introduced as a new method for the preparation of skinned asymmetric membranes. These membranes have two distinctive layers with different morphologies both from the same polymer. The top dense layer is composed of chemically crosslinked polymer chains while the bottom layer is a porous structure formed by non-crosslinked polymer chains. Such membranes were tested for vitamin B12 in solvents after either crosslinking the support or dissolving the support and fixing the freestanding membrane on alumina. Pebax® 1657 was utilized for the preparation of composite membranes by simple coating. Porous PAN membranes were coated with Pebax® 1657 which was then crosslinked using TDI. Crosslinked Pebax® membranes show high stability towards ethanol, propanol and acetone. The membranes were also stable in DMF once crosslinked PAN supports were used. Sodium alginate polymer was investigated for the preparation of thin film composite

  13. Informative document halogenated hydrocarbon-containing waste

    NARCIS (Netherlands)

    Verhagen H

    1992-01-01

    This "Informative document halogenated hydrocarbon-containing waste" forms part of a series of "Informative documents waste materials". These documents are conducted by RIVM on the instructions of the Directorate General for the Environment, Waste Materials Directorate, in behal

  14. Quantitative Hydrocarbon Energies from the PMO Method.

    Science.gov (United States)

    Cooper, Charles F.

    1979-01-01

    Details a procedure for accurately calculating the quantum mechanical energies of hydrocarbons using the perturbational molecular orbital (PMO) method, which does not require the use of a computer. (BT)

  15. Compost bioremediation of hydrocarbon-contaminated soil ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-05-16

    May 16, 2008 ... Total petroleum hydrocarbons (TPH) was reduced by 17% in the .... Identification of bacterial isolates was done by biochemical tests. Atagana 1517 ..... control the prolonged thermophilic period in two-phase olive oil mill.

  16. Infrared Spectra of Polycyclic Aromatic Hydrocarbons (PAHs)

    Science.gov (United States)

    Bauschlicher, Charles W., Jr.; Bakes, E. L. O.

    2000-01-01

    We have computed the synthetic infrared spectra of some polycyclic aromatic hydrocarbons containing up to 54 carbon atoms. The species studied include ovalene, circumcoronene, dicoronylene, and hexabenzocoronene. We report spectra for anions, neutrals, cations, and multiply charged cations.

  17. Molecular characterization of autochthonous hydrocarbon utilizing ...

    African Journals Online (AJOL)

    Hydrocarbon utilizing bacteria in water, soil and sediment samples collected from ... of the genomic DNA extracted from each bacterial isolate was amplified with ... that16S rRNA-gene-based techniques be used when studying the bacterial ...

  18. Gravity observations for hydrocarbon reservoir monitoring

    NARCIS (Netherlands)

    Glegola, M.A.

    2013-01-01

    In this thesis the added value of gravity observations for hydrocarbon reservoir monitoring and characterization is investigated. Reservoir processes and reservoir types most suitable for gravimetric monitoring are identified. Major noise sources affecting time-lapse gravimetry are analyzed. The

  19. Determination of some polycyclic aromatic hydrocarbons (PAHs ...

    African Journals Online (AJOL)

    cinthia

    2013-08-01

    Aug 1, 2013 ... In this study, polycyclic aromatic hydrocarbons (PAHs) associated with airborne particulate ... compounds from the heavily industrialized Vaal Triangle region. ... benzene ring as cluster, linear or angular (Maliszewska-.

  20. Biodegradation of polycyclic hydrocarbons by Phanerochaete chrysosporium

    Science.gov (United States)

    The ability of the white rot fungus Phanerochaete chrysosporium to degrade polycyclic aromatic hydrocarbons (PAHs) that are present in anthracene oil (a distillation product obtained from coal tar) was demonstrated. Analysis by capillary gas chromatography and high-performance li...

  1. Volatilisation of aromatic hydrocarbons from soil

    DEFF Research Database (Denmark)

    Lindhardt, B.; Christensen, T.H.

    1996-01-01

    The non-steady-state fluxes of aromatic hydrocarbons were measured in the laboratory from the surface of soils contaminated with coal tar Four soil samples from a former gasworks site were used for the experiments. The fluxes were quantified for 11 selected compounds, 4 mono- and 7 polycyclic...... aromatic hydrocarbons, for a period of up to 8 or 16 days. The concentrations of the selected compounds in the soils were between 0.2 and 3,100 mu g/g. The study included the experimental determination of the distribution coefficient of the aromatic hydrocarbons between the sorbed phase and the water under...... saturated conditions. The determined distribution coefficients showed that the aromatic hydrocarbons were more strongly sorbed to the total organic carbon including the coal tar pitch - by a factor of 8 to 25 - than expected for natural organic matter. The fluxes were also estimated using an analytical...

  2. Biodegradation of polycyclic hydrocarbons by Phanerochaete chrysosporium

    Science.gov (United States)

    The ability of the white rot fungus Phanerochaete chrysosporium to degrade polycyclic aromatic hydrocarbons (PAHs) that are present in anthracene oil (a distillation product obtained from coal tar) was demonstrated. Analysis by capillary gas chromatography and high-performance li...

  3. The orientation of solvent-dipoles at the surface of the pure solvent

    NARCIS (Netherlands)

    Nedermeijer-Denessen, H.J.M.; Ligny, C.L. de

    1975-01-01

    A method is described for the assessment of the preferential orientation of solvent-dipoles at the surface of the solvent from the surface potential χ and its temperature coefficient, dχ/dT. The method is based on the model of Levine et al. of the Stern inner region at the mercury-water interface in

  4. The orientation of solvent-dipoles at the surface of the pure solvent

    NARCIS (Netherlands)

    Nedermeijer-Denessen, H.J.M.; Ligny, C.L. de

    1975-01-01

    A method is described for the assessment of the preferential orientation of solvent-dipoles at the surface of the solvent from the surface potential χ and its temperature coefficient, dχ/dT. The method is based on the model of Levine et al. of the Stern inner region at the mercury-water interface in

  5. PSE For Solvent Applications: A Generic Computer-aided Solvent Selection and Design Framework

    DEFF Research Database (Denmark)

    Mitrofanov, Igor; Sin, Gürkan; Gani, Rafiqul

    Solvents are widely used across a number of industries in many applications such as separation agents, reaction mediums, cleaning agents and product carriers. Selection of optimal solvents in these applications is mostly based on previous experiences and experimental trial and error. A process sy...

  6. Solvent System Selection Strategies in Countercurrent Separation

    Science.gov (United States)

    Liu, Yang; Friesen, J. Brent; McAlpine, James B.; Pauli, Guido F.

    2015-01-01

    The majority of applications in countercurrent and centrifugal partition chromatography, collectively known as countercurrent separation, are dedicated to medicinal plant and natural product research. In countercurrent separation, the selection of the appropriate solvent system is of utmost importance as it is the equivalent to the simultaneous choice of column and eluent in liquid chromatography. However, solvent system selection is often laborious, involving extensive partition and/or analytical trials. Therefore, simplified solvent system selection strategies that predict the partition coefficients and, thus, analyte behavior are in high demand and may advance both the science of countercurrent separation and its applications. The last decade of solvent system selection theory and applications are critically reviewed, and strategies are classified according to their data input requirements. This offers the practitioner an up-to-date overview of rationales and methods for choosing an efficient solvent system, provides a perspective regarding their accuracy, reliability, and practicality, and discusses the possibility of combining multiple methods for enhanced prediction power. PMID:26393937

  7. Chlorinated solvent replacements recycle/recovery review report

    Energy Technology Data Exchange (ETDEWEB)

    Beal, M.; Hsu, D.; McAtee, R.E.; Weidner, J.R. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Berg, L.; McCandless, F.P.; Waltari, S.; Peterson, C. (Montana State Univ., Bozeman, MT (United States). Dept. of Chemical Engineering)

    1992-08-01

    This report is a literature review of waste solvents recycle/recovery methods and shows the results of solvent separations using membrane and distillation technologies. The experimental solvent recovery methods were conducted on solvent replacements for chlorinated solvents at Montana State University. The literature review covers waste solvents separation using distillation, membranes decantation, filtration, carbon adsorption, solvent extraction, and other vapor-phase separation techniques. The results of this study identify solvent distillation methods as the most common separation technique. The alternative separation methods typically supplement distillation. The study shows the need for industries to identify waste solvent disposal methods and investigate the economics of waste solvent recycling as a possible waste reduction method.

  8. Development of deep eutectic solvents applied in extraction and separation.

    Science.gov (United States)

    Li, Xiaoxia; Row, Kyung Ho

    2016-09-01

    Deep eutectic solvents, as an alternative to ionic liquids, have greener credentials than ionic liquids, and have attracted considerable attention in related chemical research. Deep eutectic solvents have attracted increasing attention in chemistry for the extraction and separation of various target compounds from natural products. This review highlights the preparation of deep eutectic solvents, unique properties of deep eutectic solvents, and synthesis of deep-eutectic-solvent-based materials. On the other hand, application in the extraction and separation of deep eutectic solvents is also included in this report. In this paper, the available data and references in this field are reviewed to summarize the applications and developments of deep eutectic solvents. Based on the development of deep eutectic solvents, an exploitation of new deep eutectic solvents and deep eutectic solvents-based materials is expected to diversify into extraction and separation. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Macroporous polymer foams by hydrocarbon templating

    OpenAIRE

    Shastri, Venkatram Prasad; Martin, Ivan; Langer, Robert

    2000-01-01

    Porous polymeric media (polymer foams) are utilized in a wide range of applications, such as thermal and mechanical insulators, solid supports for catalysis, and medical devices. A process for the production of polymer foams has been developed. This process, which is applicable to a wide range of polymers, uses a hydrocarbon particulate phase as a template for the precipitation of the polymer phase and subsequent pore formation. The use of a hydrocarbon template allows for enhanced control ov...

  10. Zeolitic catalytic conversion of alochols to hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-01-03

    A method for converting an alcohol to a hydrocarbon, the method comprising contacting said alcohol with a metal-loaded zeolite catalyst at a temperature of at least 100.degree. C. and up to 550.degree. C., wherein said alcohol can be produced by a fermentation process, said metal is a positively-charged metal ion, and said metal-loaded zeolite catalyst is catalytically active for converting said alcohol to said hydrocarbon.

  11. Pyrolysis of hydrocarbons from lignite semicoking tar

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Ryl' tsova, S.V.; Proskuryakov, V.A.; Rozental, D.A.; Polovetskaya, O.S.

    2000-07-01

    Pyrolysis of hydrocarbons from lignite semicoking tar in the range 750-900{degree}C at a contact time within 0.5-6.0 s was studied. The yields of pyrocarbons, pyrolysis gas, and liquid products and the group and component compositions of the liquid and gaseous products were determined. The optimal pyrolysis parameters from the viewpoint of obtaining the maximal yield of particular 'secondary' hydrocarbons were recommended.

  12. Nitrocarburising in ammonia-hydrocarbon gas mixtures

    DEFF Research Database (Denmark)

    Pedersen, Hanne; Christiansen, Thomas; Somers, Marcel A. J.

    2010-01-01

    The present work investigates the possibility of nitrocarburising in ammonia-acetylene-hydrogen and ammoniapropene- hydrogen gas mixtures, where unsaturated hydrocarbon gas is the carbon source during nitrocarburising. Consequently, nitrocarburising is carried out in a reducing atmosphere...... microscopy and X-ray diffraction analysis. It is shown that the use of unsaturated hydrocarbon gas in nitrocarburising processes is a viable alternative to traditional nitrocarburising methods....

  13. Nitrocarburizing in ammonia-hydrocarbon gas mixtures

    DEFF Research Database (Denmark)

    Pedersen, Hanne; Christiansen, Thomas; Somers, Marcel A. J.

    2011-01-01

    The present work investigates the possibility of nitrocarburising in ammonia-acetylene-hydrogen and ammonia-propene-hydrogen gas mixtures, where unsaturated hydrocarbon gas is the carbon source during nitrocarburising. Consequently, nitrocarburising is carried out in a reducing atmosphere...... microscopy and X-ray diffraction analysis. It is shown that the use of unsaturated hydrocarbon gas in nitrocarburising processes is a viable alternative to traditional nitrocarburising methods....

  14. Formation of hydrocarbons by bacteria and algae

    Energy Technology Data Exchange (ETDEWEB)

    Tornabene, T.G.

    1980-12-01

    A literature review has been performed summarizing studies on hydrocarbon synthesis by microorganisms. Certain algal and bacterial species produce hydrocarbons in large quantities, 70 to 80% of dry cell mass, when in a controlled environment. The nutritional requirements of these organisms are simple: CO/sub 2/ and mineral salts. The studies were initiated to determine whether or not microorganisms played a role in petroleum formation. 90 references. (DMC)

  15. Electrokinetic Remediation of Petroleum Hydrocarbons Spiked Soils

    OpenAIRE

    , M. Bilgin; , G. Akıncı

    2011-01-01

    In the presented study, remediation studies were conducted to determine the effectiveness of electrokinetic method on the treatment of natural soil contaminated with petroleum hydrocarbons, in laboratory scale reactors. Electokinetic remediation of agricultural soil with an initial TPHs (Total Petroleum Hydrocarbons) concentration of 10000 ppm was investigated under 20 V or 40 V direct current by using NaOH and acetic acid as electrolyte solution, treatment efficiencies were observed accordin...

  16. The future of oil and hydrocarbon man

    CERN Document Server

    Campbell, Colin

    1999-01-01

    Man appeared on the planet about four million years ago, and by 1850 numbered about one billion Ten came Hydrocarbon man. World population has since increased six-fold. After the oil price shocks of the 1970s, people asked "when will production peak?". It is not easy to answer this question because of the very poor database. Reserves and the many different hydrocarbon categories are poorly defined, reporting practices are ambiguous, revisions are not backdated...

  17. Franck-Condon factors perturbed by damped harmonic oscillators: Solvent enhanced X 1Ag ↔ A1B1u absorption and fluorescence spectra of perylene

    Science.gov (United States)

    Wang, Chen-Wen; Yang, Ling; Zhu, Chaoyuan; Yu, Jian-Guo; Lin, Sheng-Hsien

    2014-08-01

    Damped harmonic oscillators are utilized to calculate Franck-Condon factors within displaced harmonic oscillator approximation. This is practically done by scaling unperturbed Hessian matrix that represents local modes of force constants for molecule in gaseous phase, and then by diagonalizing perturbed Hessian matrix it results in direct modification of Huang-Rhys factors which represent normal modes of solute molecule perturbed by solvent environment. Scaling parameters are empirically introduced for simulating absorption and fluorescence spectra of an isolated solute molecule in solution. The present method is especially useful for simulating vibronic spectra of polycyclic aromatic hydrocarbon molecules in which hydrogen atom vibrations in solution can be scaled equally, namely the same scaling factor being applied to all hydrogen atoms in polycyclic aromatic hydrocarbons. The present method is demonstrated in simulating solvent enhanced X 1Ag ↔ A1B1u absorption and fluorescence spectra of perylene (medium-sized polycyclic aromatic hydrocarbon) in benzene solution. It is found that one of six active normal modes v10 is actually responsible to the solvent enhancement of spectra observed in experiment. Simulations from all functionals (TD) B3LYP, (TD) B3LYP35, (TD) B3LYP50, and (TD) B3LYP100 draw the same conclusion. Hence, the present method is able to adequately reproduce experimental absorption and fluorescence spectra in both gas and solution phases.

  18. Recommended methods for purification of solvents and tests for impurities

    CERN Document Server

    Coetzee, J F

    1982-01-01

    Recommended Methods for Purification of Solvents and Tests for Impurities is a compilation of recommended procedures for purification of solvents and tests for solvent impurities. Ten solvents are covered: acetonitrile, sulfolane, propylene carbonate, dimethyl sulfoxide, dimethylformamide, hexamethylphosphoramide, pyridine, ethylenediamine, N-methylacetamide, and N-methylpropionamide. This book is comprised of 12 chapters and opens with an introduction to general aspects of impurity effects. The rationale for the selection of solvent is explained, and the relative reactivities of solutes in di

  19. Electron affinities of aromatic hydrocarbons and disproportionation of their radical-anions

    Energy Technology Data Exchange (ETDEWEB)

    Szwarc, M.

    1986-09-01

    Electron affinities of aromatic hydrocarbons measured in the gas-phase and in solutions are compared. The experimental methods used for their determination are briefly reviewed. The reduction yields the respective radical-anions. Radical-anions may undergo disproportionation, a reaction described by the scheme: 2A/sup -/ . , Cat/sup =/ in equilibrium A + A/sup 2-/, 2 Cat/sup +/, K/sub dipr/. The disproportionation constant, K/sub dipr/, is greatly affected by the nature of aromatic hydrocarbon, of the cation, and of the solvent. Variation of each of these factors is illustrated. Variation of the cation and solvent results in changes of the disproportionation constant as large as factors of 10/sup 25/. The causes of these variations are rationalized and discussed in terms of the respective ..delta..H and ..delta..S. Kinetics of disproportionation was investigated by flash-photolysis techniques. The experimental approach is described. The peculiarities of Ba salts deserved some discussion to clarify the nature of those salts. The effect of disproportionation on reactions of radical-anions are described: namely on cis-trans isomerization of stilbenes, on protonation of radical-anions of anthracene an perylene, on dissociation of radical anions of aromatic derivatives ethane, etc.

  20. Hydrocarbon degradation by Antarctic coastal bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Cavanagh, J.E. [University of Tasmania, Hobart (Australia). Antarctic Cooperative Research Centre; CSIRO Div of Marine Research, Hobart (Australia); University of Tasmania, Hobart (Australia). Dept. of Agricultural Science; Nichols, P.D. [University of Tasmania, Hobart (Australia). Antarctic Cooperative Research Centre; CSIRO Div. of Marine Research, Hobart (Australia); Franzmann, P.D. [CSIRO Land and Water, Wembley (Australia); McMeekin, T.A. [University of Tasmania, Hobart (Australia). Antarctic Cooperative Research Centre

    1999-07-01

    Bacterial cultures obtained through selective enrichment of beach sand collected 60 days and one year after treatment of sites in a pilot oil spill trial conducted at Airport Beach, Vestfold Hills, East Antarctica, were examined for the ability to degrade n-alkanes and phenanthrene. The effects of different hydrocarbon mixtures (Special Antarctic Blend [SAB] and BP-Visco), (fish oil [orange roughy]) and inoculation of replicate sites with water from Organic Lake, (previously shown to contain hydrocarbon-degrading bacteria) on the indigenous microbial population, were examined. Of the cultures obtained, those from sites treated with SAB and BP-Visco degraded n-alkanes most consistently and typically to the greatest extent. Two mixed cultures obtained from samples collected at 60 days and two isolates obtained from these cultures extensively degraded phenanthrene. 1-Hydroxy-naphthoic acid formed the major phenanthrene metabolite. Lower levels of salicyclic acid, 1-naphthol, 1,4-naphthaquinone and phenanthrene 9-10 dihydrodiol were detected in extracts of phenanthrene grown cultures. This study shows that under laboratory conditions indigenous Antarctica bacteria can degrade n-alkanes and the more recalcitrant polycyclic aromatic hydrocarbon, phenanthrene. The enrichment of hydrocarbon degrading microorganisms in Antarctic ecosystems exposed to hydrocarbons, is relevant for the long term fate of hydrocarbon spills in this environment. (author)

  1. Deuterated polycyclic aromatic hydrocarbons: Revisited

    CERN Document Server

    Doney, Kirstin D; Mori, Tamami; Onaka, Takashi; Tielens, A G G M

    2016-01-01

    The amount of deuterium locked up in polycyclic aromatic hydrocarbons (PAHs) has to date been an uncertain value. We present a near-infrared (NIR) spectroscopic survey of HII regions in the Milky Way, Large Magellanic Cloud (LMC), and Small Magellanic Cloud (SMC) obtained with AKARI, which aims to search for features indicative of deuterated PAHs (PAD or Dn-PAH) to better constrain the D/H ratio of PAHs. Fifty-three HII regions were observed in the NIR (2.5-5 {\\mu}m), using the Infrared Camera (IRC) on board the AKARI satellite. Through comparison of the observed spectra with a theoretical model of deuterated PAH vibrational modes, the aromatic and (a)symmetric aliphatic C-D stretch modes were identified. We see emission features between 4.4-4.8 {\\mu}m, which could be unambiguously attributed to deuterated PAHs in only six of the observed sources, all of which are located in the Milky Way. In all cases, the aromatic C-D stretching feature is weaker than the aliphatic C-D stretching feature, and, in the case o...

  2. Birds and polycyclic aromatic hydrocarbons

    Science.gov (United States)

    Albers, P.H.

    2006-01-01

    Polycyclic aromatic hydrocarbons (PAH) are present throughout the global environment and are produced naturally and by activities of humans. Effects of PAH on birds have been determined by studies employing egg injection, egg immersion, egg shell application, single and multiple oral doses, subcutaneous injection, and chemical analysis of field-collected eggs and tissue. The four-to six-ring aromatic compounds are the most toxic to embryos, young birds, and adult birds. For embryos, effects include death, developmental abnormalities, and a variety of cellular and biochemical responses. For adult and young birds, effects include reduced egg production and hatching, increased clutch or brood abandonment, reduced growth, increased organweights, and a variety of biochemical responses. Trophic level accumulation is unlikely. Environmental exposure to PAH in areas of high human population or habitats affected by recent petroleum spills might be sufficient to adversely affect reproduction. Evidence of long-term effects of elevated concentrations of environmental PAH on bird populations is very limited and the mechanisms of effect are unclear.

  3. Microbial biodegradation of polyaromatic hydrocarbons.

    Science.gov (United States)

    Peng, Ri-He; Xiong, Ai-Sheng; Xue, Yong; Fu, Xiao-Yan; Gao, Feng; Zhao, Wei; Tian, Yong-Sheng; Yao, Quan-Hong

    2008-11-01

    Polycyclic aromatic hydrocarbons (PAHs) are widespread in various ecosystems and are pollutants of great concern due to their potential toxicity, mutagenicity and carcinogenicity. Because of their hydrophobic nature, most PAHs bind to particulates in soil and sediments, rendering them less available for biological uptake. Microbial degradation represents the major mechanism responsible for the ecological recovery of PAH-contaminated sites. The goal of this review is to provide an outline of the current knowledge of microbial PAH catabolism. In the past decade, the genetic regulation of the pathway involved in naphthalene degradation by different gram-negative and gram-positive bacteria was studied in great detail. Based on both genomic and proteomic data, a deeper understanding of some high-molecular-weight PAH degradation pathways in bacteria was provided. The ability of nonligninolytic and ligninolytic fungi to transform or metabolize PAH pollutants has received considerable attention, and the biochemical principles underlying the degradation of PAHs were examined. In addition, this review summarizes the information known about the biochemical processes that determine the fate of the individual components of PAH mixtures in polluted ecosystems. A deeper understanding of the microorganism-mediated mechanisms of catalysis of PAHs will facilitate the development of new methods to enhance the bioremediation of PAH-contaminated sites.

  4. Alternative Solvents through Green Chemistry Project

    Science.gov (United States)

    Hintze, Paul E.; Quinn, Jacqueline

    2014-01-01

    Components in the aerospace industry must perform with accuracy and precision under extreme conditions, and surface contamination can be detrimental to the desired performance, especially in cases when the components come into contact with strong oxidizers such as liquid oxygen. Therefore, precision cleaning is an important part of a components preparation prior to utilization in aerospace applications. Current cleaning technologies employ a variety of cleaning agents, many of which are halogenated solvents that are either toxic or cause environmental damage. Thus, this project seeks to identify alternative precision cleaning solvents and technologies, including use of less harmful cleaning solvents, ultrasonic and megasonic agitation, low-pressure plasma cleaning techniques, and supercritical carbon dioxide extraction. Please review all data content found in the Public Data tab located at: https:techport.nasa.govview11697public

  5. Male-limited evolution suggests no extant intralocus sexual conflict over the sexually dimorphic cuticular hydrocarbons of Drosophila melanogaster

    Indian Academy of Sciences (India)

    Stéphanie Bedhomme; Adam K. Chippindale; N. G. Prasad; Matthieu Delcourt; Jessica K. Abbott; Martin A. Mallet; Howard D. Rundle

    2011-12-01

    Sexually dimorphic traits are likely to have evolved through sexually antagonistic selection. However, recent empirical data suggest that intralocus sexual conflict often persists, even when traits have diverged between males and females. This implies that evolved dimorphism is often incomplete in resolving intralocus conflict, providing a mechanism for the maintenance of genetic variance in fitness-related traits. We used experimental evolution in Drosophila melanogaster to directly test for ongoing conflict over a suite of sexually dimorphic cuticular hydrocarbons (CHCs) that are likely targets of sex-specific selection. Using a set of experimental populations in which the transmission of genetic material had been restricted to males for 82 generations, we show that CHCs did not evolve, providing experimental evidence for the absence of current intralocus sexual conflict over these traits. The absence of ongoing conflict could indicate that CHCs have never been the target of sexually antagonistic selection, although this would require the existing dimorphism to have evolved via completely sex-linked mutations or as a result of former, but now absent, pleiotropic effects of the underlying loci on another trait under sexually antagonistic selection. An alternative interpretation, and which we believe to be more likely, is that the extensive CHC sexual dimorphism is the result of past intralocus sexual conflict that has been fully resolved, implying that these traits have evolved genetic independence between the sexes and that genetic variation in them is therefore maintained by alternative mechanisms. This latter interpretation is consistent with the known roles of CHCs in sexual communication in this species and with previous studies suggesting the genetic independence of CHCs between males and females. Nevertheless, direct estimates of sexually antagonistic selection will be important to fully resolve these alternatives.

  6. Solvent-free fluidic organic dye lasers.

    Science.gov (United States)

    Choi, Eun Young; Mager, Loic; Cham, Tran Thi; Dorkenoo, Kokou D; Fort, Alain; Wu, Jeong Weon; Barsella, Alberto; Ribierre, Jean-Charles

    2013-05-06

    We report on the demonstration of liquid organic dye lasers based on 9-(2-ethylhexyl)carbazole (EHCz), so-called liquid carbazole, doped with green- and red-emitting laser dyes. Both waveguide and Fabry-Perot type microcavity fluidic organic dye lasers were prepared by capillary action under solvent-free conditions. Cascade Förster-type energy transfer processes from liquid carbazole to laser dyes were employed to achieve color-variable amplified spontaneous emission and lasing. Overall, this study provides the first step towards the development of solvent-free fluidic organic semiconducting lasers and demonstrates a new kind of optoelectronic applications for liquid organic semiconductors.

  7. NMR spectroscopy using liquid crystal solvents

    CERN Document Server

    Emsley, JW

    2013-01-01

    NMR Spectroscopy using Liquid Crystal Solvents covers the importance of using a liquid crystal solvent in NMR to derive nuclear dipolar spin-spin coupling constants. This book is composed of ten chapters, and begins with a brief description of the features and benefits of liquid crystal in NMR spectroscopic analysis. The succeeding chapters deal with the mode of operation of nuclear spin Hamiltonian for partially oriented molecules and the analysis of NMR spectra of partially oriented molecules, as well as the determination of rigid molecule structure. These topics are followed by discussions

  8. Solvent-resistant microporous polymide membranes

    Science.gov (United States)

    Miller, Warren K.; McCray, Scott B.; Friesen, Dwayne T.

    1998-01-01

    An asymmetric microporous membrane with exceptional solvent resistance and highly desirable permeability is disclosed. The membrane is made by a solution-casting or solution-spinning process from a copolyamic acid comprising the condensation reaction product in a solvent of at least three reactants selected from certain diamines and dianhydrides and post-treated to imidize and in some cases cross-link the copolyamic acid. The membrane is useful as an uncoated membrane for ultrafiltration, microfiltration, and membrane contactor applications, or may be used as a support for a permselective coating to form a composite membrane useful in gas separations, reverse osmosis, nanofiltration, pervaporation, or vapor permeation.

  9. Hydrocarbon recovery comprising injecting a slug comprising oil soluble alkoxylated surfactants from lignin

    Energy Technology Data Exchange (ETDEWEB)

    Naae, D.G.; DaGue, M.G.; Dunn, N.G.

    1993-07-27

    A method is described of recovering hydrocarbons from an underground hydrocarbon formation penetrated by at least one injection well and at least one production well, which comprises: injecting into the formation through an injection well a surfactant slug comprising about 0.1% to about 10% by weight of oil soluble surfactants produced from lignin, said oil soluble surfactants produced by placing lignin in contact with water, converting the lignin into relatively low molecular weight lignin phenols by reducing the lignin in the presence of a reducing agent of carbon monoxide or hydrogen, said reduction occurring at a temperature greater than about 200 C and a pressure greater than about 100 psi, recovering the oil soluble lignin phenols from the reaction mixture, alkoxylating the lignin phenols by reacting the lignin phenols with an a-olefin epoxide having about 6 to about 20 carbon atoms at about 100 to about 200 C for about 1 to about 3 hours in an organic solvent, and changing the alkoxylated lignin phenols into oil soluble lignin surfactants by a reaction selected from the group consisting of sulfonation, sulfation, and alkoxysulfation; injecting into the formation through the injection well a drive fluid to push the surfactant slug towards a production well; and recovering hydrocarbons at the production well.

  10. TODGA Process Development: an Improved Solvent Formulation

    Energy Technology Data Exchange (ETDEWEB)

    Geist, Andreas [Forschungszentrum Karlsruhe, Institut fuer Nukleare Entsorgung, 76021 Karlsruhe (Germany); Modolo, Giuseppe [Forschungszentrum Juelich, Institute for Energy Research, Safety Research and Reactor Technology, 52425 Juelich (Germany)

    2009-06-15

    Introduction: TODGA (N,N,N',N'-tetra-n-octyl diglycolamide) is studied in the European ACSEPT project as a promising extractant for actinide separations. A mixture of TODGA and TBP in TPH (a kerosene) [1] was successfully used for spiked and hot continuous counter-current tests for the separation of actinides(III) and lanthanides(III) from PUREX raffinate [2, 3]. Furthermore this solvent composition is used for GANEX (group actinide extraction) process development, i.e., co-extraction of Np, Pu, Am, Cm, and Ln from PUREX raffinate with selective stripping of the actinides [4, 5]. We address two of this solvent's drawbacks by replacing TBP (which acts as phase modifier to prevent third phase formation) with 1-octanol: (1) The presence of a non-CHON compound (TBP); (2) The pronounced co-extraction of nitric acid (e.g., 0.2 M TODGA + 0.5 M TBP in TPH extracts approx. 0.6 M HNO{sub 3} from 4 M HNO{sub 3}). Results: When contacting 0.2 M TODGA in TPH with 0.1 M Nd(NO{sub 3}){sub 3} in 5 M HNO{sub 3}, as little as 3 % vol. 1-octanol suppresses the formation of a third phase. Thus, the following solvent composition is used for further studies: 0.2 M TODGA + 5 % vol. 1-octanol in TPH. Due to the absence of TBP, the amount of HNO{sub 3} extraction is reduced to approx. 50 % as compared to the solvent consisting of 0.2 M TODGA + 0.5 M TBP in TPH. Am(III) and Eu(III) distribution ratios are similar to those with the TODGA + TBP solvent [1]. Loading the solvent by extracting from solutions of up to 0.2 M Nd(NO{sub 3}){sub 3} in 3 M or 4 M HNO{sub 3} confirms a 1:3 stoichiometry of the extracted complex. Further investigations are under way. Conclusion: The improved solvent formulation reduces the HNO{sub 3} co-extraction which may be advantageous especially for GANEX process development. Furthermore, the solvent complies with the CHON principle. 1) G. Modolo, H. Asp, C. Schreinemachers, H. Vijgen, Development of a TODGA based process for partitioning of

  11. The Influence of Silica on the Reactivity of Iron Towards Chlorinated Hydrocarbons

    Science.gov (United States)

    Kohn, T.; Himmelheber, D. W.; Vikesland, P. J.; Fairbrother, D.; Roberts, A.

    2001-12-01

    Previous work has illustrated that dissolved silica present in groundwater can adsorb onto the iron media of a permeable reactive barrier. To date, little is known about the effect of adsorbed silica on the reactivity of iron towards chlorinated contaminants. Silica is a known corrosion inhibitor, and therefore silica sorption may affect the reactivity of cast iron towards redox-active species such as chlorinated ethanes. To determine the effect of silica sorption on iron reactivity towards chlorinated hydrocarbons, it is necessary to examine contaminant degradation rates under conditions where silica adsorption has been carefully accounted for. In this study we couple measurements of chlorinated hydrocarbon (CHC) (either trichloroethane (TCA) or trichloroethene) degradation rates with measurements of silica surface content. Both batch and columns studies were conducted as part of this effort. Batch studies were performed using electrolytic iron powder or iron coupons (1 cm2) in solutions containing sodium metasilicate and TCA. To evaluate the potential long-term effect of silica sorption, columns packed with untreated sieved Master Builder's iron were fed with simulated groundwater containing low levels of sodium metasilicate and chlorinated hydrocarbons (CHCs). Batch studies showed that at pH 8.5 the rate of TCA degradation decreased significantly with increasing silica concentration. Silica concentrations of 50 mg/L or more led to a two-fold decrease in the reaction rate, and a shift in the distribution of the reaction products towards less chlorinated compounds was observed. This shift could also be discerned at pH 7.5, even though the overall reaction rates were unaffected by the presence of silica. We ascribe the loss of reactivity at pH 8.5 but not at pH 7.5 to the fact that silica adsorbs onto iron more readily at higher pH. A decrease in iron reactivity towards CHCs was also observed in column experiments. Addition of silica to the feed resulted in

  12. Factors affecting high-pressure solvent extraction (accelerated solvent extraction) of additives from polymers.

    Science.gov (United States)

    Vandenburg, H J; Clifford, A A; Bartle, K D; Zhu, S A; Carroll, J; Newton, I D; Garden, L M

    1998-05-01

    Irganox 1010 (pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)] propionate) is successfully extracted from polypropylene using solvents at high temperatures and pressures in a homemade accelerated solvent extraction system. For example, using freeze-ground polymer, 90% extraction is possible within 5 min with 2-propanol at 150 °C. Extraction curves for 2-propanol and acetone fit well to the "hot ball" model, previously developed for supercritical fluid extraction. Diffusion coefficients are determined for extractions with 2-propanol, acetone, and cyclohexane over a range of temperatures, and the activation energies for the diffusion are 134, 107, and 61 kJ mol(-)(1), respectively. The lower figure for acetone and cyclohexane indicates that these solvents swell the polymer more than does 2-propanol. The polymer dissolves in the solvent at too high a temperature, which causes blockage of the transfer lines. For maximum extraction rates, the highest temperature for each solvent that avoids dissolution of the polymer should be used. The use of mixed solvents is investigated and shows advantages in some cases, with the aim of producing a solvent that will swell the polymer but not dissolve it.

  13. Experimental infrared measurements for hydrocarbon pollutant determination in subterranean waters.

    Science.gov (United States)

    Lay-Ekuakille, A; Palamara, I; Caratelli, D; Morabito, F C

    2013-01-01

    Subterranean waters are often polluted by industrial and anthropic effluents that are drained in subsoil. To prevent and control pollution, legislations of different developed countries require an online monitoring measurement, especially for detecting organic solvents (chlorinated and unchlorinated ones). Online measurements include both real-time and no real-time measurements. In general, it is difficult to implement real-time measurements in stricto sensu for online acquisitions on aqueous effluents since they need to be processed by a modeling. This research presents an experimental measurement system based on infrared (IR) spectroscopy for aqueous effluents containing hydrocarbons and capable of displaying excellent values of pollutant concentrations even in instable conditions; the system is able to detect pollutants either in laminar or turbulent flow. The results show the possibility of avoiding the use of "Pitot tube" that is employed to create a stagnation point in order to convert kinetic energy into potential one. This conversion allows the transformation of a turbulent flow in a laminar flow making easy measurement of pollutants included in an aqueous effluent. Obviously, "Pitot tube" is also used for other fluid effluents. The obtained results have been compared with those produced by means of sophisticated IR instrumentation for laboratory applications.

  14. Determination of the aromatic hydrocarbon to total hydrocarbon ratio of mineral oil in commercial lubricants.

    Science.gov (United States)

    Uematsu, Yoko; Suzuki, Kumi; Ogimoto, Mami

    2016-01-01

    A method was developed to determine the aromatic hydrocarbon to total hydrocarbon ratio of mineral oil in commercial lubricants; a survey was also conducted of commercial lubricants. Hydrocarbons in lubricants were separated from the matrix components of lubricants using a silica gel solid phase extraction (SPE) column. Normal-phase liquid chromatography (NPLC) coupled with an evaporative light-scattering detector (ELSD) was used to determine the aromatic hydrocarbon to total hydrocarbon ratio. Size exclusion chromatography (SEC) coupled with a diode array detector (DAD) and a refractive index detector (RID) was used to estimate carbon numbers and the presence of aromatic hydrocarbons, which supplemented the results obtained by NPLC/ELSD. Aromatic hydrocarbons were not detected in 12 lubricants specified for use for incidental food contact, but were detected in 13 out of 22 lubricants non-specified for incidental food contact at a ratio up to 18%. They were also detected in 10 out of 12 lubricants collected at food factories at a ratio up to 13%. The centre carbon numbers of hydrocarbons in commercial lubricants were estimated to be between C16 and C50.

  15. Next Generation Solvent Performance in the Modular Caustic Side Solvent Extraction Process - 15495

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Tara E. [Savannah River Remediation, LLC., Aiken, SC (United States); Scherman, Carl [Savannah River Remediation, LLC., Aiken, SC (United States); Martin, David [Savannah River Remediation, LLC., Aiken, SC (United States); Suggs, Patricia [Savannah River Site (SRS), Aiken, SC (United States)

    2015-01-14

    Changes to the Modular Caustic Side Solvent Extraction Unit (MCU) flow-sheet were implemented in the facility. Implementation included changing the scrub and strip chemicals and concentrations, modifying the O/A ratios for the strip, scrub, and extraction contactor banks, and blending the current BoBCalixC6 extractant-based solvent in MCU with clean MaxCalix extractant-based solvent. During the successful demonstration period, the MCU process was subject to rigorous oversight to ensure hydraulic stability and chemical/radionuclide analysis of the key process tanks (caustic wash tank, solvent hold tank, strip effluent hold tank, and decontaminated salt solution hold tank) to evaluate solvent carryover to downstream facilities and the effectiveness of cesium removal from the liquid salt waste. Results indicated the extraction of cesium was significantly more effective with an average Decontamination Factor (DF) of 1,129 (range was 107 to 1,824) and that stripping was effective. The contactor hydraulic performance was stable and satisfactory, as indicated by contactor vibration, contactor rotational speed, and flow stability; all of which remained at or near target values. Furthermore, the Solvent Hold Tank (SHT) level and specific gravity was as expected, indicating that solvent integrity and organic hydraulic stability were maintained. The coalescer performances were in the range of processing results under the BOBCalixC6 flow sheet, indicating negligible adverse impact of NGS deployment. After the Demonstration period, MCU began processing via routine operations. Results to date reiterate the enhanced cesium extraction and stripping capability of the Next Generation Solvent (NGS) flow sheet. This paper presents process performance results of the NGS Demonstration and continued operations of MCU utilizing the blended BobCalixC6-MaxCalix solvent under the NGS flowsheet.

  16. Volatile hydrocarbons inhibit methanogenic crude oil degradation

    Directory of Open Access Journals (Sweden)

    Angela eSherry

    2014-04-01

    Full Text Available Methanogenic degradation of crude oil in subsurface sediments occurs slowly, but without the need for exogenous electron acceptors, is sustained for long periods and has enormous economic and environmental consequences. Here we show that volatile hydrocarbons are inhibitory to methanogenic oil biodegradation by comparing degradation of an artificially weathered crude oil with volatile hydrocarbons removed, with the same oil that was not weathered. Volatile hydrocarbons (nC5-nC10, methylcyclohexane, benzene, toluene and xylenes were quantified in the headspace of microcosms. Aliphatic (n-alkanes nC12-nC34 and aromatic hydrocarbons (4-methylbiphenyl, 3-methylbiphenyl, 2-methylnaphthalene, 1-methylnaphthalene were quantified in the total hydrocarbon fraction extracted from the microcosms. 16S rRNA genes from key microorganisms known to play an important role in methanogenic alkane degradation (Smithella and Methanomicrobiales were quantified by quantitative PCR. Methane production from degradation of weathered oil in microcosms was rapid (1.1 ± 0.1 µmol CH4/g sediment/day with stoichiometric yields consistent with degradation of heavier n-alkanes (nC12-nC34. For non-weathered oil, degradation rates in microcosms were significantly lower (0.4 ± 0.3 µmol CH4/g sediment/day. This indicated that volatile hydrocarbons present in the non-weathered oil inhibit, but do not completely halt, methanogenic alkane biodegradation. These findings are significant with respect to rates of biodegradation of crude oils with abundant volatile hydrocarbons in anoxic, sulphate-depleted subsurface environments, such as contaminated marine sediments which have been entrained below the sulfate-reduction zone, as well as crude oil biodegradation in petroleum reservoirs and contaminated aquifers.

  17. Stepwise synthesis of (=V@CCH{sub 2}CH{sub 2}C=V@), (=V@CCH=CHC=V@), and (=V@CC=V@CC=V@) bridges between molybdenum or tungsten centers

    Energy Technology Data Exchange (ETDEWEB)

    Woodworth, B.E.; White, P.S.; Templeton, J.L. [Univ. of North Carolina, Chapel Hill, NC (United States)

    1997-01-29

    Transition metal carbide bridges (L{sub n}M(C){sub m}ML{sub n}) are an important subset of hydrocarbon bridges. In this paper, we report a family of dinuclear biscarbyne complexes displaying CH{sub 2}CH{sub 2}, CH=CH, and C=VC linkages. We have been able to access the unusual M=V@CC=V@CC=V@M framework by stepwise proton removal and subsequent oxidation to effect net dihydrogen removal from the original -CH{sub 2}CH{sub 2}- linkage to form -CH=@CH- and -C=V@C- tethers between the two robust metal carbyne moieties. The role of the metal centers in housing the negative charges at the intermediate dianion stage is essential to the oxidation sequence that has been achieved. 23 refs., 1 fig.

  18. Used Solvent Testing and Reclamation. Volume 2. Vapor Degreasing and Precision Cleaning Solvents

    Science.gov (United States)

    1988-12-01

    Dependence of the 1,3-Dioxolane/AlCI 3 Reaction Using Arrhenius’ Law 88 36 Effect of 1,4-Dioxane on Reactor Pressure 91 67 Effect of 1,4-Dioxane on HCI...and spent solvent. This process was performed for all of the three solvents. Inhibitor Kinetic Studies Batch Reactions. Batch reactor kinetic studies...acceptor in chlorinated solvents. It is an 4 80. Levenspiel , Chemical Reaction Engineering, 2nd ed. (John Wiley and Sons, 1972), pp 41-86. 490

  19. Controlling Actinide Hydration in Mixed Solvent Systems: Towards Tunable Solvent Systems to Close the Fuel Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Clark, Sue B. [Washington State Univ., Pullman, WA (United States). Dept. of Chemistry

    2016-10-31

    The goal of this project has been to define the extent of hydration the f-elements and other cations in mixed solvent electrolyte systems. Methanol-water and other mixed solvent systems have been studied, where the solvent dielectric constant was varied systematically. Thermodynamic and spectroscopic studies provide details concerning the energetics of complexation and other reactions of these cations. This information has also been used to advance new understanding of the behavior of these cations in a variety of systems, ranging from environmental studies, chromatographic approaches, and ionization processes for mass spectrometry.

  20. Solvent tuned single molecule dual emission in protic solvents: effect of polarity and H-bonding.

    Science.gov (United States)

    Chevreux, S; Allain, C; Wilbraham, L; Nakatani, K; Jacques, P; Ciofini, I; Lemercier, G

    2015-01-01

    Phen-PENMe2 has recently been proposed as a promising new molecule displaying solvent-tuned dual emission, highlighting an original and newly-described charge transfer model. The study of the photophysical behaviour of this molecule was extended to include protic solvents. The effects of polarity and hydrogen bonding lead to an even more evident dual emission associated with a large multi-emission band in some solvents like methanol, highlighting Phen-PENMe2 as a promising candidate for white light emission.

  1. Computer-Aided Solvent Screening for Biocatalysis

    DEFF Research Database (Denmark)

    Abildskov, Jens; Leeuwen, M.B. van; Boeriu, C.G.;

    2013-01-01

    . Esterification of acrylic acid with octanol is also addressed. Solvents are screened and candidates identified, confirming existing experimental results. Although the examples involve lipases, the method is quite general, so there seems to be no preclusion against application to other biocatalysts....

  2. Selective solvent absorption in coal conversion

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, J.W.; Lapucha, A.; Lazarov, L.; Amui, J.

    1992-04-01

    The objectives of this project are: (1) to determine the importance of the presence of added hydrogen donor compounds within the coal in the first stage of direct liquefaction processes; and (2) to determine the composition of the solvent absorbed by and present within the coal in the first stage of direct coal liquefaction.

  3. Spherical polymer brushes under good solvent conditions

    DEFF Research Database (Denmark)

    Lo Verso, Federica; Egorov, Sergei A.; Milchev, Andrey

    2010-01-01

    A coarse grained model for flexible polymers end-grafted to repulsive spherical nanoparticles is studied for various chain lengths and grafting densities under good solvent conditions by molecular dynamics methods and density functional theory. With increasing chain length, the monomer density...

  4. Organic solvents in electromembrane extraction: recent insights

    DEFF Research Database (Denmark)

    Huang, Chuixiu; Gjelstad, Astrid; Pedersen-Bjergaard, Stig

    2016-01-01

    Electromembrane extraction (EME) was invented in 2006 as a miniaturized sample preparation technique for the separation of ionized species from aqueous samples. This concept has been investigated in different areas of analytical chemistry by different research groups worldwide since the introduct......Electromembrane extraction (EME) was invented in 2006 as a miniaturized sample preparation technique for the separation of ionized species from aqueous samples. This concept has been investigated in different areas of analytical chemistry by different research groups worldwide since...... the introduction. Under the influence of an electrical field, EME is based on electrokinetic migration of the analytes through a supported liquid membrane (SLM), which is an organic solvent immobilized in the pores of the polymeric membrane, and into the acceptor solution. Up to date, close to 150 research...... articles with focus on EME have been published. The current review summarizes the performance of EME with different organic solvents and discusses several criteria for efficient solvents in EME. In addition, the authors highlight their personal perspective about the most promising organic solvents for EME...

  5. Mixed Solvent Reactive Recrystallization of Sodium Carbonate

    NARCIS (Netherlands)

    Gaertner, R.S.

    2005-01-01

    Investigation of the reactive recrystallization of trona (sodium sesquicarbonate) and sodium bicarbonate to sodium carbonate (soda) in a mixed solvent led to the design of several alternative, less energy consumptive, economically very attractive process routes for the production of soda from all pr

  6. THE TRAVELLING SOLVENT METHOD OF CRYSTAL GROWTH

    Science.gov (United States)

    dicumene Electron beam melting of Cr on SiC Wetting studies of Cr on SiC in different ambients Etching studies in molten salts Zone movement studies Ga-GaAs System P-N junction formation by solvent doping

  7. Organic solvent nanofiltration: prospects and application

    Energy Technology Data Exchange (ETDEWEB)

    Volkov, A V; Korneeva, G A; Tereshchenko, Gennadii F [A. V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, Moscow (Russian Federation)

    2008-11-30

    The key lines of research in a new field of the membrane science and technology, viz., organic solvent nanofiltration, are considered. The prospects for its use in chemical, petrochemical and food industries are discussed. Attention is focused on membranes developed for this method.

  8. ESES: Software for Eulerian solvent excluded surface.

    Science.gov (United States)

    Liu, Beibei; Wang, Bao; Zhao, Rundong; Tong, Yiying; Wei, Guo-Wei

    2017-03-15

    Solvent excluded surface (SES) is one of the most popular surface definitions in biophysics and molecular biology. In addition to its usage in biomolecular visualization, it has been widely used in implicit solvent models, in which SES is usually immersed in a Cartesian mesh. Therefore, it is important to construct SESs in the Eulerian representation for biophysical modeling and computation. This work describes a software package called Eulerian solvent excluded surface (ESES) for the generation of accurate SESs in Cartesian grids. ESES offers the description of the solvent and solute domains by specifying all the intersection points between the SES and the Cartesian grid lines. Additionally, the interface normal at each intersection point is evaluated. Furthermore, for a given biomolecule, the ESES software not only provides the whole surface area, but also partitions the surface area according to atomic types. Homology theory is utilized to detect topological features, such as loops and cavities, on the complex formed by the SES. The sizes of loops and cavities are measured based on persistent homology with an evolutionary partial differential equation-based filtration. ESES is extensively validated by surface visualization, electrostatic solvation free energy computation, surface area and volume calculations, and loop and cavity detection and their size estimation. We used the Amber PBSA test set in our electrostatic solvation energy, area, and volume validations. Our results are either calibrated by analytical values or compared with those from the MSMS software. © 2017 Wiley Periodicals, Inc.

  9. Expanding solvent SAGD in heavy oil reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Govind, P.A. [Society of Petroleum Engineers, Canadian Section, Calgary, AB (Canada)]|[ConocoPhillips Canada Resources Corp., Calgary, AB (Canada); Das, S.; Wheeler, T.J. [Society of Petroleum Engineers, Richardson, TX (United States)]|[ConocoPhillips Co., Houston, TX (United States); Srinivasan, S. [Society of Petroleum Engineers, Richardson, TX (United States)]|[Texas Univ., Austin, TX (United States)

    2008-10-15

    Steam assisted gravity drainage (SAGD) projects have proven effective for the recovery of oil and bitumen. Expanding solvent (ES) SAGD pilot projects have also demonstrated positive results of improved performance. This paper presented the results of a simulation study that investigated several important factors of the ES-SAGD process, including solvent types; concentration; operating pressure; and injection strategy. The objectives of the study were to examine the effectiveness of the ES-SAGD process in terms of production acceleration and energy requirements; to optimize solvent selection; to understand the effect of dilation in unconsolidated oil sands and the directional impact on reservoir parameters and oil production rate in ES-SAGD; and to understand the impact of operating conditions such as pressure, solvent concentration, circulation preheating period and the role of conduction heating and grid size in this process. The advantages of ES-SAGD over SAGD were also outlined. The paper presented results of sensitivity studies that were conducted on these four factors. Conclusions and recommendations for operating strategy were also offered. It was concluded that dilation is an important factor for SAGD performance at high operating pressure. 8 refs., 15 figs.

  10. Solvent-Free Synthesis of Chalcones

    Science.gov (United States)

    Palleros, Daniel R.

    2004-01-01

    The synthesis of twenty different chalcones in the absence of solvent is presented. The results indicated that out of the twenty different chalcones investigated seventeen can be obtained in a matter of minutes by mixing the corresponding benzaldehyde and acetophenone in the presence of solid NaOH in a mortar with pestle.

  11. Tetradecyltrimethylammonium bromide water-in-oil microemulsions: dependence of the minimum amount of alkanol required to produce a microemulsion with the alkanol and organic solvent topology.

    Science.gov (United States)

    Abuin, E; Lissi, E; Olivares, K

    2004-08-01

    The amount of alcohol required to produce a microemulsion in a quaternary water-in-oil system was evaluated for a series of alcohols and hydrocarbon solvents of different size or topology. It was observed that the amount of n-hexanol and n-decanol required was similar in all the solvents considered. On the other hand, considerably higher concentrations of the branched alcohols (2,4-dimethyl-3-pentanol and 3-ethyl-3-pentanol) were required to produce the microemulsion, irrespective of the solvent topology (n-hexane or 2,2,4-trimethylpentane). From an analysis of the change in the analytical alcohol concentration with the surfactant concentration the amounts of alcohol present at the microaggregates' surface at the point of microemulsion formation were obtained. It is concluded that the high amounts of branched alcohols required are due to both less efficient incorporation at the interface and the larger number of alcohol molecules per surfactant required to stabilize the microemulsion.

  12. Solvent density mode instability in non-polar solutions

    Indian Academy of Sciences (India)

    Susmita Kar; Ranjit Biswas; J Chakrabarti

    2008-08-01

    We analyse the origin of the multiple long time scales associated with the long time decay observed in non-polar solvation dynamics by linear stability analysis of solvent density modes where the effects of compressibility and solvent structure are systematically incorporated. The coupling of the solute–solvent interactions at both ground and excited states of the solute with the compressibility and solvent structure is found to have important effects on the time scales. The present theory suggests that the relatively longer time constant is controlled by the solvent compressibility, while the solvent structure at the nearest-neighbour length scale dominates the shorter time constant.

  13. Foaming of mixtures of pure hydrocarbons

    Science.gov (United States)

    Robinson, J. V.; Woods, W. W.

    1950-01-01

    Mixtures of pure liquid hydrocarbons are capable of foaming. Nine hydrocarbons were mixed in pairs, in all possible combinations, and four proportions of each combination. These mixtures were sealed in glass tubes, and the foaming was tested by shaking. Mixtures of aliphatic with other aliphatic hydrocarbons, or of alkyl benzenes with other alkyl benzenes, did not foam. Mixtures of aliphatic hydrocarbons with alkyl benzenes did foam. The proportions of the mixtures greatly affected the foaming, the maximum foaming of 12 of 20 pairs being at the composition 20 percent aliphatic hydrocarbon, 80 percent alkyl benzene. Six seconds was the maximum foam lifetime of any of these mixtures. Aeroshell 120 lubricating oil was fractionated into 52 fractions and a residue by extraction with acetone in a fractionating extractor. The index of refraction, foam lifetime, color, and viscosity of these fractions were measured. Low viscosity and high index fractions were extracted first. The viscosity of the fractions extracted rose and the index decreased as fractionation proceeded. Foam lifetimes and color were lowest in the middle fractions. Significance is attached to the observation that none of the foam lifetimes of the fractions or residue is as high as the foam lifetime of the original Aeroshell, indicating that the foaming is not due to a particular foaming constituent, but rather to the entire mixture.

  14. Syngas Upgrading to Hydrocarbon Fuels Technology Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Talmadge, M.; Biddy, Mary J.; Dutta, Abhijit; Jones, Susanne B.; Meyer, Pimphan A.

    2013-03-31

    In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to hydrocarbon fuels to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This pathway case investigates the upgrading of biomass derived synthesis gas (‘syngas’) to hydrocarbon biofuels. While this specific discussion focuses on the conversion of syngas via a methanol intermediate to hydrocarbon blendstocks, there are a number of alternative conversion routes for production of hydrocarbons through a wide array of intermediates from syngas. Future work will also consider the variations to this pathway to determine the most economically viable and risk adverse conversion route. Technical barriers and key research needs have been identified that should be pursued for the syngas to hydrocarbon pathway to be competitive with petroleum-derived gasoline, diesel and jet range blendstocks.

  15. Velocity Dependence of Friction of Confined Hydrocarbons

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Samoilov, Vladimir N.; Persson, Bo N. J.

    2010-01-01

    We present molecular dynamics friction calculations for confined hydrocarbon “polymer” solids with molecular lengths from 20 to 1400 carbon atoms. Two cases are considered: (a) polymer sliding against a hard substrate and (b) polymer sliding on polymer. We discuss the velocity dependence of the f......We present molecular dynamics friction calculations for confined hydrocarbon “polymer” solids with molecular lengths from 20 to 1400 carbon atoms. Two cases are considered: (a) polymer sliding against a hard substrate and (b) polymer sliding on polymer. We discuss the velocity dependence...... in the polymer film is always close to the thermostat temperature. In the first setup (a), for hydrocarbons with molecular lengths from 60 to 1400 carbon atoms, the shear stresses are nearly independent of molecular length, but for the shortest hydrocarbon C20H42 the frictional shear stress is lower. In all...... cases the frictional shear stress increases monotonically with the sliding velocity. For polymer sliding on polymer (case b) the friction is much larger, and the velocity dependence is more complex. For hydrocarbons with molecular lengths from 60 to 140 C atoms, the number of monolayers of lubricant...

  16. Direct-immersion solid-phase microextraction coupled to fast gas chromatography mass spectrometry as a purification step for polycyclic aromatic hydrocarbons determination in olive oil.

    Science.gov (United States)

    Purcaro, Giorgia; Picardo, Massimo; Barp, Laura; Moret, Sabrina; Conte, Lanfranco S

    2013-09-13

    The aim of the present work was to optimize a preparation step for polycyclic aromatic hydrocarbons in a fatty extract. Solid-phase microextraction is an easy preparation technique, which allows to minimize solvent consumption and reduce sample manipulation. A Carbopack Z/polydimethylsiloxane fiber, particularly suitable for extraction of planar compounds, was employed to extract polycyclic aromatic hydrocarbons from a hexane solution obtained after a previous extraction with acetonitrile from oil, followed by a liquid-liquid partition between acetonitrile and hexane. The proposed method was a rapid and sensitive solution to reduce the interference of triglycerides saving the column life and avoiding frequent cleaning of the mass spectrometer ion source. Despite the non-quantitative extraction of polycyclic aromatic hydrocarbons from oil using acetonitrile, the signal-to-noise ratio was significantly improved obtaining a limit of detection largely below the performance criteria required by the European Union legislation.

  17. Ionic liquids and deep eutectic solvents in natural products research: mixtures of solids as extraction solvents.

    Science.gov (United States)

    Dai, Yuntao; van Spronsen, Jaap; Witkamp, Geert-Jan; Verpoorte, Robert; Choi, Young Hae

    2013-11-22

    Mixtures of solid chemicals may become liquid under certain conditions. These liquids are characterized by the formation of strong ionic (ionic liquids) or hydrogen bonds (deep eutectic solvents). Due to their extremely low vapor pressure, they are now widely used in polymer chemistry and synthetic organic chemistry, yet little attention has been paid to their use as extraction solvents of natural products. This review summarizes the preparation of ionic liquids and deep eutectic solvents with natural product components and recent progress in their applications to the extraction and analysis of natural products as well as the recovery of extracted compounds from their extracts. Additionally, various factors affecting extraction features of ionic liquids and deep eutectic solvents, as well as potential useful technologies including microwave and ultrasound to increase the extraction efficiency, are discussed.

  18. Paleozoic Hydrocarbon-Seep Limestones

    Science.gov (United States)

    Peckmann, J.

    2007-12-01

    To date, five Paleozoic hydrocarbon-seep limestones have been recognized based on carbonate fabrics, associated fauna, and stable carbon isotopes. These are the Middle Devonian Hollard Mound from the Antiatlas of Morocco [1], Late Devonian limestone lenses with the dimerelloid brachiopod Dzieduszyckia from the Western Meseta of Morocco [2], Middle Mississippian limestones with the dimerelloid brachiopod Ibergirhynchia from the Harz Mountains of Germany [3], Early Pennsylvanian limestones from the Tantes Mound in the High Pyrenees of France [4], and Late Pennsylvanian limestone lenses from the Ganigobis Shale Member of southern Namibia [5]. Among these examples, the composition of seepage fluids varied substantially as inferred from delta C-13 values of early diagenetic carbonate phases. Delta C-13 values as low as -50 per mil from the Tantes Mound and -51 per mil from the Ganigobis limestones reveal seepage of biogenic methane, whereas values of -12 per mil from limestones with Dzieduszyckia associated with abundant pyrobitumen agree with oil seepage. Intermediate delta C-13 values of carbonate cements from the Hollard Mound and Ibergirhynchia deposits probably reflect seepage of thermogenic methane. It is presently very difficult to assess the faunal evolution at seeps in the Paleozoic based on the limited number of examples. Two of the known seeps were typified by extremely abundant rhynchonellide brachiopods of the superfamily Dimerelloidea. Bivalve mollusks and tubeworms were abundant at two of the known Paleozoic seep sites; one was dominated by bivalve mollusks (Hollard Mound, Middle Devonian), another was dominated by tubeworms (Ganigobis Shale Member, Late Pennsylvanian). The tubeworms from these two deposits are interpreted to represent vestimentiferan worms, based on studies of the taphonomy of modern vestimentiferans. However, this interpretation is in conflict with the estimated evolutionary age of vestimentiferans based on molecular clock methods

  19. Comparison of solvent mixtures for pressurized solvent extraction of soil fatty acid biomarkers.

    Science.gov (United States)

    Jeannotte, Richard; Hamel, Chantal; Jabaji, Suha; Whalen, Joann K

    2008-10-19

    The extraction and transesterification of soil lipids into fatty acid methyl esters (FAMEs) is a useful technique for studying soil microbial communities. The objective of this study was to find the best solvent mixture to extract soil lipids with a pressurized solvent extractor system. Four solvent mixtures were selected for testing: chloroform:methanol:phosphate buffer (1:2:0.8, v/v/v), chloroform:methanol (1:2, v/v), hexane:2-propanol (3:2, v/v) and acetone. Soils were from agricultural fields and had a wide range of clay, organic matter and microbial biomass contents. Total lipid fatty acid methyl esters (TL-FAMEs) were the extractable soil lipids identified and quantified with gas chromatography and flame ionization detection. Concentrations of TL-FAMEs ranged from 57.3 to 542.2 nmole g(-1) soil (dry weight basis). The highest concentrations of TL-FAMEs were extracted with chloroform:methanol:buffer or chloroform:methanol mixtures than with the hexane:2-propanol or acetone solvents. The concentrations of TL-FAMEs in chemical groups, including saturated, branched, mono- and poly-unsaturated and hydroxy fatty acids were assessed, and biological groups (soil bacteria, mycorrhizal fungi, saprophytic fungi and higher plants) was distinguished. The extraction efficiency for the chemical and biological groups followed the general trend of: chloroform:methanol:buffer> or =chloroform:methanol>hexane:2-propanol=acetone. Discriminant analysis revealed differences in TL-FAME profiles based on the solvent mixture and the soil type. Although solvent mixtures containing chloroform and methanol were the most efficient for extracting lipids from the agricultural soils in this study, soil properties and the lipid groups to be studied should be considered when selecting a solvent mixture. According to our knowledge, this is the first report of soil lipid extraction with hexane:2-propanol or acetone in a pressurized solvent extraction system.

  20. Biodiesel production from ethanolysis of palm oil using deep eutectic solvent (DES) as co-solvent

    Science.gov (United States)

    Manurung, R.; Winarta, A.; Taslim; Indra, L.

    2017-06-01

    Biodiesel produced from ethanolysis is more renewable and have better properties (higher oxidation stability, lower cloud and pour point) compared to methanolysis, but it has a disadvantage such as complicated purification. To improve ethanolysis process, deep eutectic solvent (DES) can be prepared from choline chloride and glycerol and used as co-solvent in ethanolysis. The deep eutectic solvent is formed from a quaternary ammonium salt (choline chloride) and a hydrogen bond donor (Glycerol), it is a non-toxic, biodegradable solvent compared to a conventional volatile organic solvent such as hexane. The deep eutectic solvent is prepared by mixing choline chloride and glycerol with molar ratio 1:2 at temperature 80 °C, stirring speed 300 rpm for 1 hour. The DES is characterized by its density and viscosity. The ethanolysis is performed at a reaction temperature of 70 °C, ethanol to oil molar ratio of 9:1, potassium hydroxide as catalyst concentration of 1.2 wt. DES as co-solvent with concentration 0.5 to 3 wt. stirring speed 400 rpm, and a reaction time 1 hour. The obtained biodiesel is then characterized by its density, viscosity, and ester content. The oil - ethanol phase condition is observed in the reaction tube. The oil - ethanol phase with DES tends to form meniscus compared to without DES, showed that oil and ethanol become more slightly miscible, which favors the reaction. Using DES as co-solvent in ethanolysis showed increasing in yield and easier purification. The esters properties meet the international standards ASTM D6751, with the highest yield achieved 83,67 with 99,77 conversion at DES concentration 2 . Increasing DES concentration above 2 in ethanolysis decrease the conversion and yield, because of the excessive glycerol in the systems makes the reaction equilibrium moves to the reactant side.

  1. Relative ototoxicity of 21 aromatic solvents

    Energy Technology Data Exchange (ETDEWEB)

    Gagnaire, Francois; Langlais, Cristina [Institut National de Recherche et de Securite, Departement Polluants et Sante, Vandoeuvre (France)

    2005-06-01

    Some aromatic solvents (e.g. toluene, p-xylene, styrene, and ethylbenzene) show, in the rat, striking ototoxicity characterized by an irreversible hearing loss, as measured by behavioural or electrophysiological methods, associated with damage to outer hair cells in the cochlea of the exposed animals. To broaden the range of aromatic solvents studied concerning their potential ototoxicity and to compare their ototoxicity quantitatively, 21 aromatic solvents were administered orally by gastric intubation to Sprague-Dawley rats for 5 days/week for a 2-week period. The dose used was 8.47 mmol kg{sup -1} body weight day{sup -1}. The possible ototoxicity of the aromatic solvents was evaluated by morphological investigation of the cochlea. Whole-mount surface preparations of the organ of Corti were made to quantify the number of missing hair cells (cytocochleogram). Among the 21 solvents studied, eight (toluene, p-xylene, ethylbenzene, n-propylbenzene, styrene, {alpha}-methylstyrene, trans-{beta}-methylstyrene, and allylbenzene) caused histological lesions of the organ of Corti. They differed widely in their potency. The least ototoxic solvents caused outer hair cell (OHC) loss in the middle turn of the organ of Corti. The OHC loss was slight in the first row, and greater in the second and third rows. The most ototoxic solvents caused high losses in the three rows of the outer hair cells along the entire length of the basilar membrane. There were also occasional inner hair cell (ICH) losses in the most affected animals. Although no measurements were made of the chemical concentrations reached in the blood or the brain, tentative ranking of an increasing ototoxicity of the eight aromatic solvents could be proposed on the basis of the histological losses observed - {alpha}-methylstyrene

  2. Electrochemical Routes towards Sustainable Hydrocarbon Fuels

    DEFF Research Database (Denmark)

    Mogensen, Mogens Bjerg

    2012-01-01

    The potential of renewable energy and possible solution to the intermittency problem of renewable energy sources like sun and wind are explained. The densest storage of energy is in the form of hydrocarbons. The most suitable method of conversion and storage within a foreseeable future is electro......The potential of renewable energy and possible solution to the intermittency problem of renewable energy sources like sun and wind are explained. The densest storage of energy is in the form of hydrocarbons. The most suitable method of conversion and storage within a foreseeable future...... is electrolysis followed by conversion into synthetic hydrocarbons, alcohols or ethers. Several types of electrolysers exist. The various types are listed together with a short description of principle and status. It is argued that electrolysis will at least become part of large sustainable energy systems...

  3. Reappraisal of hydrocarbon biomarkers in Archean rocks

    Science.gov (United States)

    French, Katherine L.; Hallmann, Christian; Hope, Janet M.; Schoon, Petra L.; Zumberge, J. Alex; Hoshino, Yosuke; Peters, Carl A.; George, Simon C.; Love, Gordon D.; Brocks, Jochen J.; Buick, Roger; Summons, Roger E.

    2015-05-01

    Hopanes and steranes found in Archean rocks have been presented as key evidence supporting the early rise of oxygenic photosynthesis and eukaryotes, but the syngeneity of these hydrocarbon biomarkers is controversial. To resolve this debate, we performed a multilaboratory study of new cores from the Pilbara Craton, Australia, that were drilled and sampled using unprecedented hydrocarbon-clean protocols. Hopanes and steranes in rock extracts and hydropyrolysates from these new cores were typically at or below our femtogram detection limit, but when they were detectable, they had total hopane (oxygenic photosynthesis and eukaryotes by ∼2.7 billion years ago. Although suitable Proterozoic rocks exist, no currently known Archean strata lie within the appropriate thermal maturity window for syngenetic hydrocarbon biomarker preservation, so future exploration for Archean biomarkers should screen for rocks with milder thermal histories.

  4. EVALUATION OF PETROLEUM HYDROCARBONS ELUTION FROM SOIL

    Directory of Open Access Journals (Sweden)

    Janina Piekutin

    2015-06-01

    Full Text Available The paper presents studies on oil removal from soil by means of water elution with a help of shaking out the contaminants from the soil. The tests were performed on simulated soil samples contaminated with a mixture of petroleum hydrocarbons. The study consisted in recording the time influence and the number of elution cycles to remove contaminants from the soil. The samples were then subject to the determination of petroleum hydrocarbons, aliphatic hydrocarbons, and BTEX compounds (benzene, toluene, ethylbenzene, xylene. Due to adding various concentrations of petroleum into particular soil samples and applying different shaking times, it was possible to find out the impact of petroleum content and sample shaking duration on the course and possibility of petroleum substances removal by means of elution process.

  5. Hydrocarbon Degrading Bacteria: Isolation and Identification

    Directory of Open Access Journals (Sweden)

    Lies Indah Sutiknowati

    2007-11-01

    Full Text Available There is little information how to identify hydrocarbon degrading bacteria for bioremediation of marine oil spills. We have used gravel which contaminated oil mousse from Beach Simulator Tank, in Marine Biotechnology Institute, Kamaishi, Japan, and grown on enrichment culture. Biostimulation with nutrients (N and P was done to analyze biodegradation of hydrocarbon compounds: Naphthalene, Phenanthrene, Trichlorodibenzofuran and Benzo[a]pyrene. Community of bacteria from enrichment culture was determined by DGGE. Isolating and screening the bacteria on inorganic medium contain hydrocarbon compounds and determination of bacteria by DAPI (number of cells and CFU. DNA was extracted from colonies of bacteria and sequence determination of the 16S rDNA was amplified by primers U515f and U1492r. Twenty nine strains had been sequence and have similarity about 90-99% to their closest taxa by homology Blast search and few of them have suspected as new species.

  6. Using supercritical fluids to refine hydrocarbons

    Science.gov (United States)

    Yarbro, Stephen Lee

    2014-11-25

    This is a method to reactively refine hydrocarbons, such as heavy oils with API gravities of less than 20.degree. and bitumen-like hydrocarbons with viscosities greater than 1000 cp at standard temperature and pressure using a selected fluid at supercritical conditions. The reaction portion of the method delivers lighter weight, more volatile hydrocarbons to an attached contacting device that operates in mixed subcritical or supercritical modes. This separates the reaction products into portions that are viable for use or sale without further conventional refining and hydro-processing techniques. This method produces valuable products with fewer processing steps, lower costs, increased worker safety due to less processing and handling, allow greater opportunity for new oil field development and subsequent positive economic impact, reduce related carbon dioxide, and wastes typical with conventional refineries.

  7. Artificial Hydrocarbon Networks Fuzzy Inference System

    Directory of Open Access Journals (Sweden)

    Hiram Ponce

    2013-01-01

    Full Text Available This paper presents a novel fuzzy inference model based on artificial hydrocarbon networks, a computational algorithm for modeling problems based on chemical hydrocarbon compounds. In particular, the proposed fuzzy-molecular inference model (FIM-model uses molecular units of information to partition the output space in the defuzzification step. Moreover, these molecules are linguistic units that can be partially understandable due to the organized structure of the topology and metadata parameters involved in artificial hydrocarbon networks. In addition, a position controller for a direct current (DC motor was implemented using the proposed FIM-model in type-1 and type-2 fuzzy inference systems. Experimental results demonstrate that the fuzzy-molecular inference model can be applied as an alternative of type-2 Mamdani’s fuzzy control systems because the set of molecular units can deal with dynamic uncertainties mostly present in real-world control applications.

  8. Bioremediation of Petroleum Hydrocarbon Contaminated Sites

    Energy Technology Data Exchange (ETDEWEB)

    Fallgren, Paul

    2009-03-30

    Bioremediation has been widely applied in the restoration of petroleum hydrocarbon-contaminated. Parameters that may affect the rate and efficiency of biodegradation include temperature, moisture, salinity, nutrient availability, microbial species, and type and concentration of contaminants. Other factors can also affect the success of the bioremediation treatment of contaminants, such as climatic conditions, soil type, soil permeability, contaminant distribution and concentration, and drainage. Western Research Institute in conjunction with TechLink Environmental, Inc. and the U.S. Department of Energy conducted laboratory studies to evaluate major parameters that contribute to the bioremediation of petroleum-contaminated drill cuttings using land farming and to develop a biotreatment cell to expedite biodegradation of hydrocarbons. Physical characteristics such as soil texture, hydraulic conductivity, and water retention were determined for the petroleum hydrocarbon contaminated soil. Soil texture was determined to be loamy sand to sand, and high hydraulic conductivity and low water retention was observed. Temperature appeared to have the greatest influence on biodegradation rates where high temperatures (>50 C) favored biodegradation. High nitrogen content in the form of ammonium enhanced biodegradation as well did the presence of water near field water holding capacity. Urea was not a good source of nitrogen and has detrimental effects for bioremediation for this site soil. Artificial sea water had little effect on biodegradation rates, but biodegradation rates decreased after increasing the concentrations of salts. Biotreatment cell (biocell) tests demonstrated hydrocarbon biodegradation can be enhanced substantially when utilizing a leachate recirculation design where a 72% reduction of hydrocarbon concentration was observed with a 72-h period at a treatment temperature of 50 C. Overall, this study demonstrates the investigation of the effects of

  9. The presence of hydrocarbons in southeast Norway

    DEFF Research Database (Denmark)

    Hanken, Niels Martin; Hansen, Malene Dolberg; Kresten Nielsen, Jesper

    Hydrocarbons, mostly found as solid pyrobitumen, are known from more than 30 localities in southeast Norway. They occur as inclusions in a wide range of "reservoir rocks" spanning from Permo-Carboniferous breccias to veins (vein quartz and calcite veins) in Precambrian granites, gneisses and amph......Hydrocarbons, mostly found as solid pyrobitumen, are known from more than 30 localities in southeast Norway. They occur as inclusions in a wide range of "reservoir rocks" spanning from Permo-Carboniferous breccias to veins (vein quartz and calcite veins) in Precambrian granites, gneisses...

  10. Mathematics of Periodic Tables for Benzenoid Hydrocarbons.

    Science.gov (United States)

    Dias, Jerry Ray

    2007-01-01

    The upper and lower bounds for invariants of polyhex systems based on the Harary and Harborth inequalities are studied. It is shown that these invariants are uniquely correlated by the Periodic Table for Benzenoid Hydrocarbons. A modified periodic table for total resonant sextet (TRS) benzenoids based on the invariants of Ds and r(empty) is presented; Ds is the number of disconnections among the empty rings for fused TRS benzenoid hydrocarbons. This work represents a contribution toward deciphering the topological information content of benzenoid formulas.

  11. Electrochemical removal of NOx and hydrocarbons

    DEFF Research Database (Denmark)

    Friedberg, Anja Zarah

    on the electrodes during polarisation, probably because of strong adsorption of the hydrocarbon relative to NO. On LSF/CGO electrode the impregnation of ionic conducting material increased the oxidation of NO to NO2 which is an important step before nitrogen formation. The propene inhibited this reaction because....... This could only be done if the electrode was impregnated with BaO. The nitrate formation did not seem to be inhibited by the presence of the hydrocarbon. However, the oxidation of propene was inhibited by the BaO because the active sites for oxidations were partially covered by the BaO nanoparticles...

  12. Transferable Tight-Binding Potential for Hydrocarbons

    CERN Document Server

    Wang, Y; Wang, Yang

    1994-01-01

    A transferable tight-binding potential has been constructed for heteroatomic systems containing carbon and hydrogen. The electronic degree of freedom is treated explicitly in this potential using a small set of transferable parameters which has been fitted to small hydrocarbons and radicals. Transferability to other higher hydrocarbons were tested by comparison with ab initio calculations and experimental data. The potential can correctly reproduce changes in the electronic configuration as a function of the local bonding geometry around each carbon atom. This type of potential is well suited for computer simulations of covalently bonded systems in both gas-phase and condensed-phase systems.

  13. 29 CFR 1915.32 - Toxic cleaning solvents.

    Science.gov (United States)

    2010-07-01

    ... Preservation § 1915.32 Toxic cleaning solvents. (a) When toxic solvents are used, the employer shall employ one... space. (2) Either natural ventilation or mechanical exhaust ventilation shall be used to remove the...

  14. Organic Solvent Tropical Report [SEC 1 and 2

    Energy Technology Data Exchange (ETDEWEB)

    COWLEY, W.L.

    2000-06-21

    This report provides the basis for closing the organic solvent safety issue. Sufficient information is presented to conclude that risk posed by an unmitigated organic solvent fire is within risk evaluation guidelines.

  15. Occupational exposure to chlorinated and petroleum solvents and mycosis fungoides

    DEFF Research Database (Denmark)

    Morales-Suárez-Varela, Maria M; Olsen, Jørn; Villeneuve, Sara

    2013-01-01

    To evaluate the potential association between occupational exposure to chlorinated and petroleum solvents and mycosis fungoides (MF).......To evaluate the potential association between occupational exposure to chlorinated and petroleum solvents and mycosis fungoides (MF)....

  16. The Ideal Solvent for Paper Chromatography of Food Dyes.

    Science.gov (United States)

    Markow, Peter G.

    1988-01-01

    Uses paper chromatography with food dyes to provide a simple and inexpensive basis for teaching chromatography. Provides experimental methodology and tabled results. Includes a solvent system comparison (Rf) for seven dyes and twenty-two solvents. (MVL)

  17. Effect of solvents on propylene epoxidation over TS-1 catalyst

    Institute of Scientific and Technical Information of China (English)

    Yulong WU; Qingshan LIU; Xueli SU; Zhentao MI

    2008-01-01

    Solvents have an important effect on the epoxidation of propylene catalyzed by TS-1. The experimental results show that, in different solvents, the catalytic activity of epoxidation is in the following order: methanol > 2-propanol > 2-butanol > acetoni-trile > acetone > tetrahydrofuran. Based on the reaction mechanism, the effects of solvents on the epoxidation were studied from eight aspects, which included the electronic effect, the steric effect, the polarity of solvent, the effect of solvent on sorption and diffusion of reactant, the oxidation of alcohol, the etherification of PO, the deactivation of TS-1 and the solubility of propylene in the solvents. The electronic effect, steric effect and the polarity of solvent were considered to be the main aspects. This work may provide theoretical guidance for choosing solvents for these kinds of reactions and also may serve as basis for further industrialization.

  18. A solvent/non-solvent system for achieving solution-processed multilayer organic light-emitting devices

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Yue; Wu, Zhaoxin, E-mail: zhaoxinwu@mail.xjtu.edu.cn; He, Lin; Jiao, Bo; Hou, Xun

    2015-08-31

    We developed a solvent/non-solvent system to fabricate the multilayer organic light-emitting devices (OLEDs) based on poly(N-vinylcarbazole) (PVK) by solution-process. This solvent system consists of both the solvent and non-solvent of PVK, in which fluorescent small molecules could be fully dissolved and directly spin-coated on top of the PVK layer; it could effectively avoid the redissolution of PVK during the spin-coating process of small molecules emitting layer. In the further investigation of this system, we also demonstrated the three-component solvent system, and found out that the third component, a less volatile solvent of PVK, was crucial for preparing a smoother interface between PVK and emitting layer. Compared with OLEDs through the vacuum deposition, the devices fabricated by solution-process from the solvent/non-solvent system showed comparable efficiency, which indicate that the solvent/non-solvent system can be used as an alternative process to prepare the polymer and small molecule multilayer devices through all-solution-process. - Highlights: • We fabricate the multilayer OLEDs by solution-process using a novel system. • We develop a solvent/non-solvent system of polymer (PVK) to avoid redissolution. • Small molecules could be fully dissolved and directly spin-coated on PVK layer. • The devices fabricated by the system and vacuum deposition show comparable efficiency.

  19. Cuticular hydrocarbons and aggression in the termite Macrotermes subhyalinus.

    Science.gov (United States)

    Kaib, Manfred; Jmhasly, Patrick; Wilfert, Lena; Durka, Walter; Franke, Stephan; Francke, Wittko; Leuthold, Reinhard H; Brandl, Roland

    2004-02-01

    Cuticular hydrocarbons are among the prime candidates for nestmate recognition in social insects. We analyzed the variation of cuticular hydrocarbons in the termite species M. subhyalinus in West Africa (Comoë National Park) on a small spatial scale (recognition.

  20. NMR microscopy of tissue in organic and mixed solvents

    OpenAIRE

    Macura Slobodan; Mishra Prasanna K.; Gamez Jeffrey D.; Pirko Istvan

    2013-01-01

    We propose to use organic and mixed solvents for nuclear magnetic resonance microscopy of fixed tissue as a means for improving image information content. NMR properties of some standard solvents (methanol, acetone, DMSO) and solvents in use for tissue processing in pathology (xylenes, paraffin, ‘Clearify’) have been measured, reviewed, and analyzed. It was found that DMSO and paraffin are very useful solvents that provide images of better quality than thos...

  1. Functionalization of graphene using deep eutectic solvents

    Science.gov (United States)

    Hayyan, Maan; Abo-Hamad, Ali; AlSaadi, Mohammed AbdulHakim; Hashim, Mohd Ali

    2015-08-01

    Deep eutectic solvents (DESs) have received attention in various applications because of their distinctive properties. In this work, DESs were used as functionalizing agents for graphene due to their potential to introduce new functional groups and cause other surface modifications. Eighteen different types of ammonium- and phosphonium-salt-based DESs were prepared and characterized by FTIR. The graphene was characterized by FTIR, STA, Raman spectroscopy, XRD, SEM, and TEM. Additional experiments were performed to study the dispersion behavior of the functionalized graphene in different solvents. The DESs exhibited both reduction and functionalization effects on DES-treated graphene. Dispersion stability was investigated and then characterized by UV-vis spectroscopy and zeta potential. DES-modified graphene can be used in many applications, such as drug delivery, wastewater treatment, catalysts, composite materials, nanofluids, and biosensors. To the best of our knowledge, this is the first investigation on the use of DESs for graphene functionalization.

  2. Alternative solvents for post combustion carbon capture

    Directory of Open Access Journals (Sweden)

    Udara S. P. R. Arachchige, Morten C. Melaaen

    2013-01-01

    Full Text Available The process model of post combustion chemical absorption is developed in Aspen Plus for both coal and gas fired power plant flue gas treating. The re-boiler energy requirement is considered as the most important factor to be optimized. Two types of solvents, mono-ethylamine (MEA and di-ethylamine (DEA, are used to implement the model for three different efficiencies. The re-boiler energy requirement for regeneration process is calculated. Temperature and concentration profiles in absorption column are analyzed to understand the model behavior. Re-boiler energy requirement is considerably lower for DEA than MEA as well as impact of corrosion also less in DEA. Therefore, DEA can be recommended as a better solvent for post combustion process for carbon capture plants in fossil fuel fired power industries.

  3. Myoglobin solvent structure at different temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, B.V.; Korszun, Z.R. [Brookhaven National Laboratory, Upton, NY (United States); Schoenborn, B.P. [Los Alamos National Laboratory, NM (United States)

    1994-12-31

    The structure of the solvent surrounding myoglobin crystals has been analyzed using neutron diffraction data, and the results indicate that the water around the protein is not disordered, but rather lies in well-defined hydration shells. We have analyzed the structure of the solvent surrounding the protein by collecting neutron diffraction data at four different temperatures, namely, 80, 130, 180, and 240K. Relative Wilson Statistics applied to low resolution data showed evidence of a phase transition in the region of 180K. A plot of the liquidity factor, B{sub sn}, versus distance from the protein surface begins with a high plateau near the surface of the protein and drops to two minima at distances from the protein surface of about 2.35{Angstrom} and 3.85{Angstrom}. Two distinct hydration shells are observed. Both hydration shells are observed to expand as the temperature is increased.

  4. Critical bubble radius in solvent sublation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The complex compound of dithizone-Co(Ⅱ) was separated and concentrated from the aqueous phase to n-octanol by solvent sublation. From the analysis of the coalescence behavior of bubbles on water-organic interface, the conception of critical bubble radius was proposed, and the value of the critical bubble radius in the water-octanol system was obtained: 1.196 × 10-3 m. The simulation of the mathematical model using CBR and experimental data is completed with perfect results, and the simulation of the mathematical model using CBR is very different with the classic one. The analytical results proved that the critical bubble radius should be adequately considered in mathematical model of solvent sublation.

  5. High performance hydrophobic solvent, carbon dioxide capture

    Energy Technology Data Exchange (ETDEWEB)

    Nulwala, Hunaid; Luebke, David

    2017-05-09

    Methods and compositions useful, for example, for physical solvent carbon capture. A method comprising: contacting at least one first composition comprising carbon dioxide with at least one second composition to at least partially dissolve the carbon dioxide of the first composition in the second composition, wherein the second composition comprises at least one siloxane compound which is covalently modified with at least one non-siloxane group comprising at least one heteroatom. Polydimethylsiloxane (PDMS) materials and ethylene-glycol based materials have high carbon dioxide solubility but suffer from various problems. PDMS is hydrophobic but suffers from low selectivity. Ethylene-glycol based systems have good solubility and selectivity, but suffer from high affinity to water. Solvents were developed which keep the desired combinations of properties, and result in a simplified, overall process for carbon dioxide removal from a mixed gas stream.

  6. Alternative solvents for post combustion carbon capture

    Energy Technology Data Exchange (ETDEWEB)

    Arachchige, Udara S.P.R. [Telemark University College, Porsgrunn (Norway); Melaaen, Morten C. [Telemark University College, Porsgrunn (Norway); Tel-Tek, Porsgrunn (Norway)

    2013-07-01

    The process model of post combustion chemical absorption is developed in Aspen Plus for both coal and gas fired power plant flue gas treating. The re-boiler energy requirement is considered as the most important factor to be optimized. Two types of solvents, mono-ethylamine (MEA) and di-ethylamine (DEA), are used to implement the model for three different efficiencies. The re-boiler energy requirement for regeneration process is calculated. Temperature and concentration profiles in absorption column are analyzed to understand the model behavior. Re-boiler energy requirement is considerably lower for DEA than MEA as well as impact of corrosion also less in DEA. Therefore, DEA can be recommended as a better solvent for post combustion process for carbon capture plants in fossil fuel fired power industries.

  7. Effect of water droplet in solvent sublation

    Institute of Scientific and Technical Information of China (English)

    Peng Yu Bi; Hui Ru Dong; Nan Nan Wang

    2008-01-01

    Aqueous phase layer around bubble and water droplet are two additional processes in solvent sublation. In the dynamic processof mass transfer, they are always neglected, but they are very important in the investigation of thermodynamic equilibrium. In thispaper, the effect of water droplet in solvent sublation was discussed in detail, and the previous mathematical model of solventsubaltion was improved. Matlab 6.5 was used to simulate the process of water droplets, and the comparison between the previoushypothesis and the improvement in this paper showed the superiority, especially in the investigation of thermodynamic equilibrium.Moreover, the separation and concentration of the complex compound dithizone-Co(Ⅱ) from aqueous phase to n-octanol by solventsublation also proved the improved mathematical model was reasonable.2008 Hui Ru Dong. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

  8. Development of a solvent processed insensitive propellant

    Science.gov (United States)

    Trask, R.; Costa, E.; Beardell, A. J.

    1980-01-01

    Two types of low vulnerability propellants are studied which are distinguished by whether the binder is a rubber, such as polyurethane or CTBN, or a plasticizable polymer such as ethyl cellulose or cellulose acetate. The former propellants are made by a partial cure extrusion process while the latter are made by the conventional solvent process. Emphasis is given to a cellulose binder (plasticizer) RDX composition. The type of binder used, the particle size of the RDX and the presence of small quantities of nitrocellulose in the solvent processed compositions have important influences on the mechanical and combustion characteristics of the propellant. The low temperature combustion is of particular concern because of potential breakup of the grains that can lead to instability.

  9. Solvent extraction of Southern US tar sands

    Energy Technology Data Exchange (ETDEWEB)

    Penney, W.R.

    1990-01-01

    The Department of Chemical Engineering at the University of Arkansas, in association with Diversified Petroleum Recovery, Inc. (DPR) of Little Rock, Arkansas, has been developing a solvent extraction process for the recovery of bitumen from tar sands for the past five years. The unique feature of the process is that the bitumen is recovered from the solvent by contacting with a co-solvent, which causes the bitumen to precipitate. The overall purpose of this project is to study both the technical and economic feasibility of applying this technology for recovery of bitumen from tar sands by (1) investigating the socioeconmic factors which affect (a) plant siting and (b) the market value of recovered bitumen; (2) operating a process demonstration unit at the rate of 1 lb/hr recovered bitumen while producing clean sand and recyclable solvents; and (3) determine the economic conditions which will make a bitumen recovery project economical. DPR has analyzed the historical trends of domestic production, consumption, discoveries and reserves of crude oil. They have started an investigation of the volatility in the price of crude oil and of gasoline prices and of the differential between gasoline and crude oil. DPR continues to analyze the geographical movement and demand for asphalt products. Utah does not appear economically attractive as a site for a bitumen from tar sands asphalt plant. Oklahoma sites are now being studied. This report also contains the quarterly progress report from a University of Nevada study to determine bitumen composition, oxygen uptake rates, and viscosities of Alabama and Utah bitumens. Both reports have been indexed separately for inclusion on the data base.

  10. Solvent extraction of Southern US tar sands

    Energy Technology Data Exchange (ETDEWEB)

    Penney, W.R.

    1990-01-01

    The Department of Chemical Engineering at the University of Arkansas, in association with Diversified Petroleum Recovery, Inc. (DPR) of Little Rock, Arkansas, has been developing a solvent extraction process for the recovery of bitumen from tar sands for the past five years. The unique feature of the process is that the bitumen is recovered from the solvent by contacting with a co-solvent, which causes the bitumen to precipitate. The overall purpose of this project is to study both the technical and economic feasibility of applying this technology for recovery of bitumen from tar sands by (1) investigating the socioeconmic factors which affect (a) plant siting and (b) the market value of recovered bitumen; (2) operating a process demonstration unit at the rate of 1 lb/hr recovered bitumen while producing clean sand and recyclable solvents; and (3) determine the economic conditions which will make a bitumen recovery project economical. DPR has analyzed the historical trends of domestic production, consumption, discoveries and reserves of crude oil. They have started an investigation of the volatility in the price of crude oil and of gasoline prices and of the differential between gasoline and crude oil. DPR continues to analyze the geographical movement and demand for asphalt products. Utah does not appear economically attractive as a site for a bitumen from tar sands asphalt plant. Oklahoma sites are now being studied. This report also contains the quarterly progress report from a University of Nevada study to determine bitumen composition, oxygen uptake rates, and viscosities of Alabama and Utah bitumens. Both reports have been indexed separately for inclusion on the data base.

  11. Solvent Retention Capacities of Oat Flour

    Directory of Open Access Journals (Sweden)

    Qianwen Niu

    2017-03-01

    Full Text Available This study measured the solvent retention capacities (SRCs of flours from eight oat varieties and one wheat variety against different solvents to explore the swelling volume of oat flour with different solvents, and thus provide a theoretical basis for quick β-glucan analysis. The SRC profile consists of water SRC (WSRC, 50% sucrose SRC (SSRC, 5% lactic acid SRC (LASRC, 5% Na2CO3 SRC (SCASRC, NaCl SRC (SCSRC, CaCl2 SRC (CCSRC, FeCl3 SRC (FCSRC, sodium cholate SRC (SCHSRC, NaOH (pH 10 SRC (SHSRC, Na2CO3 (pH 10 SRC (SCABSRC and SDS (pH 10 SRC (SDSSRC values, and a Chopin SRC kit was used to measure the SRC value. SRCs of the oat flours increased when the solvents turned from neutral (water and NaCl to acidic (5% lactic acid or alkaline (5% Na2CO3, CaCl2, FeCl3, NaOH and pH 10 Na2CO3, and rose as the metal ion valencies of the metal salts (NaCl, CaCl2 and FeCl3 increased. The β-glucan contents were significantly positively correlated with the SCSRC (0.83**, CCSRC (0.82**, SCHSRC (0.80** and FCSRC (0.78*. SRC measurements of β-glucan in oat flours revealed that the CCSRC values were related with β-glucan (0.64* but not related with protein and starch. CaCl2 could therefore potentially be exploited as a reagent for β-glucan assay.

  12. Indentation of polydimethylsiloxane submerged in organic solvents

    OpenAIRE

    Hu, Yuhang; Chen, Xin; Whitesides, George McClelland; Vlassak, Joost J.; Suo, Zhigang

    2011-01-01

    This work uses a method based on indentation to characterize a polydimethylsiloxane (PDMS) elastomer submerged in an organic solvent (decane, heptane, pentane, or cyclohexane). An indenter is pressed into a disk of a swollen elastomer to a fixed depth, and the force on the indenter is recorded as a function of time. By examining how the relaxation time scales with the radius of contact, one can differentiate the poroelastic behavior from the viscoelastic behavior. By matching the relaxation c...

  13. Coupling of protein dynamics with the solvent

    Science.gov (United States)

    Caliskan, Gokhan; Sauzan, Azzam; Mehtani, Disha; Sokolov, Alexei

    2003-03-01

    Glycerol and trehalose are among the many viscous solvents that are widely used for biostabilization and controlling the dynamics of proteins. It is believed that the suppression of the structural relaxations by high viscosity of solvent is responsible for improved stability in proteins. However, results of [1] and [2] demonstrate stronger suppression of biochemical activity and dynamics of proteins by liquid glycerol than by solid trehalose in a wide temperature range. The authors tried to explain the counterintuitive observations by a possible decoupling of the dynamics of the protein from trehalose. In order to test the validity of this assumption and to investigate the influence of the fast dynamics in proteins, the low frequency Raman scattering spectroscopy technique is used. Both relaxational and vibrational dynamics of glycerol, trehalose, and lysozyme in glycerol and in trehalose are studied in a wide temperature range. Dynamics of lysozyme in glycerol follows the strong temperature dependence of relaxational and vibrational dynamics of the bulk glycerol. On the other hand, the weak temperature dependence of dynamics of lysozyme in trehalose follows exactly the behavior of pure trehalose. This proves that there is a strong dynamic coupling between the protein and the solvents used. Interestingly, stronger relaxations in solid trehalose as compared to liquid glycerol are observed in the GHz region at low temperatures. This could be the reason for the enhanced protein activity observed in trehalose, compared to that in glycerol in this temperature range. Suppression of these fast relaxations should be the key for providing long-term stability to proteins. 1. Sastry, G.M. and N. Agmon, Trehalose prevents myoglobin collapse and preserves its internal mobility. BIOCHEMISTRY, 1997, 36(23): p. 7097-108. 2. Caliskan, G., et al., Influence of solvent on dynamics and stability of a protein. Journal of Non-Crystalline Solids, 2002, 307-310: p. 887-893.

  14. Solvent Retention Capacities of Oat Flour

    Science.gov (United States)

    Niu, Qianwen; Pu, Yu; Li, Xiaoping; Ma, Zhen; Hu, Xinzhong

    2017-01-01

    This study measured the solvent retention capacities (SRCs) of flours from eight oat varieties and one wheat variety against different solvents to explore the swelling volume of oat flour with different solvents, and thus provide a theoretical basis for quick β-glucan analysis. The SRC profile consists of water SRC (WSRC), 50% sucrose SRC (SSRC), 5% lactic acid SRC (LASRC), 5% Na2CO3 SRC (SCASRC), NaCl SRC (SCSRC), CaCl2 SRC (CCSRC), FeCl3 SRC (FCSRC), sodium cholate SRC (SCHSRC), NaOH (pH 10) SRC (SHSRC), Na2CO3 (pH 10) SRC (SCABSRC) and SDS (pH 10) SRC (SDSSRC) values, and a Chopin SRC kit was used to measure the SRC value. SRCs of the oat flours increased when the solvents turned from neutral (water and NaCl) to acidic (5% lactic acid) or alkaline (5% Na2CO3, CaCl2, FeCl3, NaOH and pH 10 Na2CO3), and rose as the metal ion valencies of the metal salts (NaCl, CaCl2 and FeCl3) increased. The β-glucan contents were significantly positively correlated with the SCSRC (0.83**), CCSRC (0.82**), SCHSRC (0.80**) and FCSRC (0.78*). SRC measurements of β-glucan in oat flours revealed that the CCSRC values were related with β-glucan (0.64*) but not related with protein and starch. CaCl2 could therefore potentially be exploited as a reagent for β-glucan assay. PMID:28335393

  15. Green solvents and technologies for oil extraction from oilseeds.

    Science.gov (United States)

    Kumar, S P Jeevan; Prasad, S Rajendra; Banerjee, Rintu; Agarwal, Dinesh K; Kulkarni, Kalyani S; Ramesh, K V

    2017-01-01

    Oilseeds are crucial for the nutritional security of the global population. The conventional technology used for oil extraction from oilseeds is by solvent extraction. In solvent extraction, n-hexane is used as a solvent for its attributes such as simple recovery, non-polar nature, low latent heat of vaporization (330 kJ/kg) and high selectivity to solvents. However, usage of hexane as a solvent has lead to several repercussions such as air pollution, toxicity and harmfulness that prompted to look for alternative options. To circumvent the problem, green solvents could be a promising approach to replace solvent extraction. In this review, green solvents and technology like aqueous assisted enzyme extraction are better solution for oil extraction from oilseeds. Enzyme mediated extraction is eco-friendly, can obtain higher yields, cost-effective and aids in obtaining co-products without any damage. Enzyme technology has great potential for oil extraction in oilseed industry. Similarly, green solvents such as terpenes and ionic liquids have tremendous solvent properties that enable to extract the oil in eco-friendly manner. These green solvents and technologies are considered green owing to the attributes of energy reduction, eco-friendliness, non-toxicity and non-harmfulness. Hence, the review is mainly focussed on the prospects and challenges of green solvents and technology as the best option to replace the conventional methods without compromising the quality of the extracted products.

  16. Kinetic simulating experiment on the secondary hydrocarbon generation of kerogen

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The kinetic parameters of generation have been obtained for different hydrocarbon classes, including methane, C2-C5 gas hydrocarbons, C6-C13 light hydrocarbons and C13+ heavy hydrocarbons, and vitrinite reflectance (Ro) by the kinetic simulating experiment of kerogen cracking. Then, combined with the detailed geology of Sichuan Basin, the effective gas-generating intensity of the Lower Cambrian source rock is approximately estimated by applying these parameters.

  17. Dynamics of solvent-free grafted nanoparticles

    KAUST Repository

    Chremos, Alexandros

    2012-01-01

    The diffusivity and structural relaxation characteristics of oligomer-grafted nanoparticles have been investigated with simulations of a previously proposed coarse-grained model at atmospheric pressure. Solvent-free, polymer-grafted nanoparticles as well as grafted nanoparticles in a melt were compared to a reference system of bare (ungrafted) particles in a melt. Whereas longer chains lead to a larger hydrodynamic radius and lower relative diffusivity for grafted particles in a melt, bulk solvent-free nanoparticles with longer chains have higher relative diffusivities than their short chain counterparts. Solvent-free nanoparticles with short chains undergo a glass transition as indicated by a vanishing diffusivity, diverging structural relaxation time and the formation of body-centered-cubic-like order. Nanoparticles with longer chains exhibit a more gradual increase in the structural relaxation time with decreasing temperature and concomitantly increasing particle volume fraction. The diffusivity of the long chain nanoparticles exhibits a minimum at an intermediate temperature and volume fraction where the polymer brushes of neighboring particles overlap, but must stretch to fill the interparticle space. © 2012 American Institute of Physics.

  18. Solubility of C60 in solvent mixtures.

    Science.gov (United States)

    Kulkarni, Pradnya P; Jafvert, Chad T

    2008-02-01

    The potential large-scale production of fullerene C60 and its widespread use in consumer products may translate into occupational and public exposure and in long-term environmental exposure. To assess the risk and fate of C60 in the environment, it is important to understand its solvate formation in common industrial solvents as the solvates may affect various properties of C60 including reactivity and toxicity, particularly when solvates occur in C60 clusters. In this study, the solubility measurements in mixed solvent system can provide useful information about solvate formation. The solubility of C60 was measured in pure toluene, tetrahydrofuran, ethanol, and acetonitrile to be 3000, 11, 1.4, and 0.04 mg/L, respectively. Additionally, the solubility of C60 was measured in mixtures of toluene-acetonitrile, toluene-ethanol, toluene-tetrahydrofuran, and acetonitrile-tetrahydrofuran. The solubility data were modeled with some accuracy using Wohl's equation. The estimated crystal energy term for C60 in tetrahydrofuran was different than that in the other solvents, indicating that the C60 solid phase in equilibrium with tetrahydrofuran solution may be a solvated crystal.

  19. Use of soluble humic substances as solubilisers in the in situ rehabilitation of sites contaminated with PAH or longchain hydrocarbons from crude oil. Final report; Einsatz von loeslichen Huminstoffen als Loesungsvermittler bei der In-situ-Sanierung von PAK- und laengerkettigen Mineraloelkohlenwasserstoff-Schadensfaellen. Endbericht

    Energy Technology Data Exchange (ETDEWEB)

    Koerdel, W.; Kloeppel, H. [Fraunhofer-Institut fuer Umweltchemie und Oekotoxikologie, Schmallenberg (Germany); Gohlke, U. [Fraunhofer-Institut fuer Angewandte Polymerforschung, Teltow (Germany); Schulz-Berendt, V.; Koopmann [Umweltschutz Nord GmbH, Ganderkesee (Germany)

    1999-12-14

    The purpose of the present project was to demonstrate in example model experiments the suitability of DOM solutions, which can easily be derived from composts, for in situ rehabilitation and to compare the success achieved with remediation results obtained using surfactants and coffeein. The model experiments were carried out according to the DECHEMA guide to ''Laboratory methods for assessing biological soil rehabilitation'' using glass columns (of 14 cm dia. and 60 cm length) containing one of two different PAH-contaminated soils (PAH I and PAH II) or a soil contaminated with crude oil hydrocarbons (CHC). Altogether a markedly enhanced leaching of pollutants (PAH and CHC) from the soils as well as an increased degradation of contaminants was observed during the experiments, and there were no negative accompanying processes such as excessive bacterial growth, occlusion of soil pores or excessive accumulation of DOM in the soil. In terms of posing a hazard to groundwater natural humic substances are certainly to be viewed as less critical than synthetic detergents. [German] Ziel des Vorhabens war es, die Eignung von DOM-Loesungen, die aus Komposten leicht gewonnen werden koennen, in der In-situ-Sanierung exemplarisch anhand von Modellversuchen aufzuzeigen und den erzielten Sanierungserfolg mit dem von Tensiden und Coffein zu vergleichen. Die Modelluntersuchungen erfolgten gemaess DECHEMA-Leitfaden 'Labormethoden zur Beurteilung der biologischen Bodensanierung' unter Verwendung von Glassaeulen (14 cm diameter, 60 cm Laenge) mit zwei PAK-belasteten Boeden (PAK I und PAK II) sowie einem mit Mineraloelkohlenwasserstoffen belasteten Boden (MKW-Boden). Insgesamt konnte mit natuerlichen DOM-Loesungen eine deutlich gesteigerte Auswaschung der Schadstoffe (PAK und MKW) aus den Boeden waehrend des Versuchs als auch ein gesteigerter Abbau der Kontaminanten erreicht werden, ohne dass negative Begleitprozesse wie zu starkes Bakterienwachstum und

  20. Development of an improved analytical method for the determination of carcinogenic polycyclic aromatic hydrocarbons in transformer oil.

    Science.gov (United States)

    Pillai, I; Ritchie, L; Heywood, R; Wilson, G; Pahlavanpour, B; Setford, S; Saini, S

    2005-02-04

    Polynuclear aromatic hydrocarbons (PAHs) are natural constituents of transformer oils and are essential in prolonging transformer in-service lifetime. Issues concerning PAH carcinogenicity demand methods that provide qualitative and quantitative information on the PAH composition of new and in-service oils to allow informed operational decisions to be made. However, current analytical methods focus on PAH fingerprinting, as opposed to quantitative analysis and are also cumbersome, relying on the use of large (>100 ml) volumes of organic solvents, some of which are hazardous. This paper reports a method for the improved quantification of carcinogenic PAHs in transformer oils that is both simple and repeatable. The method uses commercially available solid-phase extraction columns and millilitre volumes of relatively non-hazardous solvents. Extraction efficiencies of > or =74% were obtained for the Environmental Protection Agency priority PAHs. The method has potential for automation and high-throughput analysis and thus is of interest to industries that use transformer oils.