Sample records for benzene toluene xylene

  1. Detection of Benzene, Toluene, Ethyl Benzene, and Xylenes (BTEX) Using Toluene Dioxygenase-Peroxidase Coupling Reactions

    E-Print Network [OSTI]

    Chen, Wilfred

    Detection of Benzene, Toluene, Ethyl Benzene, and Xylenes (BTEX) Using Toluene Dioxygenase, whole-cell bioassay for the detection of bioavailable benzene, toluene, ethyl benzene, and xylenes (BTEX of the response obtained from the blank) of 10, 10, 20, and 50 µM was observed for benzene, toluene, ethyl benzene

  2. Primary and Secondary Glyoxal Formation from Aromatics: Experimental Evidence for the Bicycloalkyl-Radical Pathway from Benzene, Toluene, and p-Xylene

    E-Print Network [OSTI]

    -Radical Pathway from Benzene, Toluene, and p-Xylene R. Volkamer,*, U. Platt, and K. Wirtz Centro de Estudios Form: May 16, 2001 A new approach is presented to study the ring-cleavage process of benzene, toluene for the troposphere. The yield of glyoxal was determined to be 35% ( 10% for benzene and about 5% higher for toluene

  3. Genotoxicity and apoptosis in Drosophila melanogaster exposed to benzene, toluene and xylene: Attenuation by quercetin and curcumin

    SciTech Connect (OSTI)

    Singh, Mahendra P. [Embryotoxicology Section, Indian Institute of Toxicology Research (CSIR), Mahatma Gandhi Marg, Lucknow 226001, Uttar Pradesh (India); Mishra, M.; Sharma, A.; Shukla, A.K. [Embryotoxicology Section, Indian Institute of Toxicology Research (CSIR), Mahatma Gandhi Marg, Lucknow 226001, Uttar Pradesh (India); Council of Scientific and Industrial Research (CSIR), New Delhi (India); Mudiam, M.K.R.; Patel, D.K. [Analytical Chemistry Section, Indian Institute of Toxicology Research, Mahatma Gandhi Marg, Lucknow 226 001, Uttar Pradesh (India); Council of Scientific and Industrial Research (CSIR), New Delhi (India); Ram, K. Ravi [Embryotoxicology Section, Indian Institute of Toxicology Research (CSIR), Mahatma Gandhi Marg, Lucknow 226001, Uttar Pradesh (India); Council of Scientific and Industrial Research (CSIR), New Delhi (India); Chowdhuri, D. Kar, E-mail: dkarchowdhuri@rediffmail.com [Embryotoxicology Section, Indian Institute of Toxicology Research (CSIR), Mahatma Gandhi Marg, Lucknow 226001, Uttar Pradesh (India); Council of Scientific and Industrial Research (CSIR), New Delhi (India)

    2011-05-15T23:59:59.000Z

    Monocyclic aromatic hydrocarbons (MAHs) such as benzene, toluene and xylene are being extensively used for various industrial and household purposes. Exposure to these hydrocarbons, occupationally or non-occupationally, is harmful to organisms including human. Several studies tested for toxicity of benzene, toluene and xylene, and interestingly, only a few studies looked into the attenuation. We used Drosophila model to test the genotoxic and apoptotic potential of these compounds and subsequently evaluated the efficiency of two phytochemicals, namely, quercetin and curcumin in attenuating test chemical induced toxicity. We exposed third instar larvae of wild type Drosophila melanogaster (Oregon R{sup +}) to 1.0-100.0 mM benzene, toluene or xylene, individually, for 12, 24 and 48 h and examined their apoptotic and genotoxic potential. We observed significantly (P < 0.001) increased apoptotic markers and genotoxicity in a concentration- and time-dependent manner in organisms exposed to benzene, toluene or xylene. We also observed significantly (P < 0.001) increased cytochrome P450 activity in larvae exposed to test chemicals and this was significantly reduced in the presence of 3',4'-dimethoxyflavone, a known Aryl hydrocarbon receptor (AhR) blocker. Interestingly, we observed a significant reduction in cytochrome P450 activity, GST levels, oxidative stress parameters, genotoxic and apoptotic endpoints when organisms were exposed simultaneously to test chemical along with quercetin or curcumin. The study further suggests the suitability of D. melanogaster as an alternate animal model for toxicological studies involving benzene, toluene and xylene and its potential in studying the protective role(s) of phytochemicals.

  4. www.rsc.org/analyst The airliquid interface of benzene, toluene, m-xylene, and

    E-Print Network [OSTI]

    ANALYST FULLPAPER THE www.rsc.org/analyst The air­liquid interface of benzene, toluene, m as an Advance Article on the web 10th April 2003 The air­liquid interface and the liquid-phase of benzene-zero hyperpolarizabilities of benzene and 1,3,5-trimethylbenzene. The orientation of the aromatic rings of these compounds

  5. Liquid-liquid equilibria for the ternary systems sulfolane + octane + benzene, sulfolane + octane + toluene and sulfolane + octane + p-xylene

    SciTech Connect (OSTI)

    Lee, S.; Kim, H. [Seoul National Univ. (Korea, Republic of). Dept. of Chemical Engineering

    1995-03-01T23:59:59.000Z

    Sulfolane is widely used as a solvent for the extraction of aromatic hydrocarbons. Ternary phase equilibrium data are essential for the proper understanding of the solvent extraction process. Liquid-liquid equilibrium data for the systems sulfolane + octane + benzene, sulfolane + octane + toluene and sulfolane + octane + p-xylene were determined at 298.15, 308.15, and 318.15 K. Tie line data were satisfactorily correlated by the Othmer and Tobias method. The experimental data were compared with the values calculated by the UNIQUAC and NRTL models. Good quantitative agreement was obtained with these models. However, the calculated values based on the NRTL model were found to be better than those based on the UNIQUAC model.

  6. Reactions of the CN Radical with Benzene and Toluene: Product Detection and Low-Temperature Kinetics

    E-Print Network [OSTI]

    Trevitt, Adam J.

    2010-01-01T23:59:59.000Z

    of the CN Radical with Benzene and Toluene: Productare measured for the CN + benzene and CN + toluene reactionsdetection. The CN + benzene reaction rate coefficient at

  7. Quaternary liquid-liquid equilibrium of n-heptane-toluene-o-xylene-propylene carbonate

    SciTech Connect (OSTI)

    Salem, A.B.S.H.; Hamad, E.Z.; Al-Naafa, M.A. (King Fahd Univ. of Petroleum and Minerals, Dhahran (Saudi Arabia). Chemical Engineering Dept.)

    1994-03-01T23:59:59.000Z

    Liquid-liquid equilibrium data for the system n-heptane/toluene/o-xylene/propylene carbonate were obtained at 25 OC. Experimental tie line data were measured by gas chromatographic analysis. The UNIQUAC and NRTL models were used to predict the quaternary data from the corresponding ternary data. Agreement between the predictions and the experimental data was satisfactory.

  8. Low temperature oxidation of benzene and toluene in mixture with ndecane

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Low temperature oxidation of benzene and toluene in mixture with ndecane Olivier Herbinet Abstract The oxidation of two blends, benzene/ndecane and toluene/ndecane, was studied in a jetstirred of benzene, only phenol could be quantified. In the case of toluene, significant amounts

  9. Mechanistic Studies of Reactions of Peroxodiiron(III) Intermediates in T201 Variants of Toluene/o-Xylene Monooxygenase Hydroxylase

    E-Print Network [OSTI]

    Lippard, Stephen J.

    Site-directed mutagenesis studies of a strictly conserved T201 residue in the active site of toluene/o-xylene monooxygenase hydroxylase (ToMOH) revealed that a single mutation can facilitate kinetic isolation of two ...

  10. Assessment of dermal exposure to benzene and toluene in shoe manufacturing by activated carbon cloth patches

    E-Print Network [OSTI]

    California at Berkeley, University of

    Assessment of dermal exposure to benzene and toluene in shoe manufacturing by activated carbon activated carbon cloth (ACC) patches to study the probability and extent of dermal exposure to benzene for the contribution from the air through passive absorption of benzene and toluene on the ACC patches. Systemic

  11. Multiple Roles of Component Proteins in Bacterial Multicomponent Monooxygenases: Phenol Hydroxylase and Toluene/o-Xylene Monooxygenase from Pseudomonas sp. OX1

    E-Print Network [OSTI]

    Tinberg, Christine E.

    Phenol hydroxylase (PH) and toluene/o-xylene monooxygenase (ToMO) from Pseudomonas sp. OX1 require three or four protein components to activate dioxygen for the oxidation of aromatic substrates at a carboxylate-bridged ...

  12. Correlation of the phase equilibrium data for the heptane-toluene-sulfolane and heptane-xylene-sulfolane systems

    SciTech Connect (OSTI)

    Cassell, G.W.; Hassan, M.M.; Hines, A.L. (Univ. of Missouri, Dept. of Chemical Engineering, Columbia, MO (US))

    1989-10-01T23:59:59.000Z

    Liquid-liquid equilibrium data were measured for the heptane-toluene-sulfolane system at 25{sup 0}C and for the heptane-xylene-sulfolane system at 17, 25, and 50{sup 0}C. The NRTL and UNIQUAC equations are used to correlate the experimental data and to predict the phase compositions of the ternary systems. The agreement between the predicted and the experimental results was equally good with both equations.

  13. Autoignition of toluene and benzene at elevated pressures in a rapid compression machine

    SciTech Connect (OSTI)

    Mittal, Gaurav; Sung, Chih-Jen [Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH 44106 (United States)

    2007-09-15T23:59:59.000Z

    Autoignition of toluene and benzene is investigated in a rapid compression machine at conditions relevant to HCCI (homogeneous charge compression ignition) combustion. Experiments are conducted for homogeneous mixtures over a range of equivalence ratios at compressed pressures from 25 to 45 bar and compressed temperatures from 920 to 1100 K. Experiments varying oxygen concentration while keeping the mole fraction of toluene constant reveal a strong influence of oxygen in promoting ignition. Additional experiments varying fuel mole fraction at a fixed equivalence ratio show that ignition delay becomes shorter with increasing fuel concentration. Moreover, autoignition of benzene shows significantly higher activation energy than that of toluene. In addition, the experimental pressure traces for toluene show behavior of heat release significantly different from the results of Davidson et al. [D.F. Davidson, B.M. Gauthier, R.K. Hanson, Proc. Combust. Inst. 30 (2005) 1175-1182]. Predictability of various detailed kinetic mechanisms is also compared. Results demonstrate that the existing mechanisms for toluene and benzene fail to predict the experimental data with respect to ignition delay and heat release. Flux analysis is further conducted to identify the dominant reaction pathways and the reactions responsible for the mismatch of experimental and simulated data. (author)

  14. Characterization of a Peroxodiiron(III) Intermediate in the T201S Variant of Toluene/o-Xylene Monooxygenase Hydroxylase from Pseudomonas sp. OX1

    E-Print Network [OSTI]

    Song, Woon Ju

    We report the observation of a novel intermediate in the reaction of a reduced toluene/o-xylene monooxygenase hydroxylase (ToMOH[subscript red]) T201S variant, in the presence of a regulatory protein (ToMOD), with dioxygen. ...

  15. Reactions of the CN Radical with Benzene and Toluene: Product Detection and Low-Temperature Kinetics

    SciTech Connect (OSTI)

    Trevitt, Adam J.; Goulay, Fabien; Taatjes, Craig A.; Osborn, David L.; Leone, Stephen R.

    2009-12-23T23:59:59.000Z

    Low temperature rate coefficients are measured for the CN + benzene and CN + toluene reactions using the pulsed Laval nozzle expansion technique coupled with laser-induced fluorescence detection. The CN + benzene reaction rate coefficient at 105, 165 and 295 K is found to be relatively constant over this temperature range, 3.9 - 4.9 x 10-10 cm3 molecule-1 s-1. These rapid kinetics, along with the observed negligible temperature dependence, are consistent with a barrierless reaction entrance channel and reaction efficiencies approaching unity. The CN + toluene reaction is measured to have a slower rate coefficient of 1.3 x 10-10 cm3 molecule-1 s-1 at 105 K. At room temperature, non-exponential decay profiles are observed for this reaction that may suggest significant back-dissociation of intermediate complexes. In separate experiments, the products of these reactions are probed at room temperature using synchrotron VUV photoionization mass spectrometry. For CN + benzene, cyanobenzene (C6H5CN) is the only product recorded with no detectable evidence for a C6H5 + HCN product channel. In the case of CN + toluene, cyanotoluene (NCC6H4CH3) constitutes the only detected product. It is not possible to differentiate among the ortho, meta and para isomers of cyanotoluene because of their similar ionization energies and the ~;; 40 meV photon energy resolution of the experiment. There is no significant detection of benzyl radicals (C6H5CH2) that would suggest a H-abstraction or a HCN elimination channel is prominent at these conditions. As both reactions are measured to be rapid at 105 K, appearing to have barrierless entrance channels, it follows that they will proceed efficiently at the temperatures of Saturn?s moon Titan (~;;100 K) and are also likely to proceed at the temperature of interstellar clouds (10-20 K).

  16. The atmospheric release of benzene, toluene, ethylbenzene, and xylene from contaminated soils

    E-Print Network [OSTI]

    Ramsey, Ronald Roland

    1993-01-01T23:59:59.000Z

    ,000 sites will be reported leaking by 1997. The Environmental Protection Agency (EPA) estimates that it will take 20 to 30 years and an average of $ 1 00, 000 to $400, 000 per site to remediate all sites. Many techniques have been developed...

  17. Mobility of Supercooled liquid Toluene, Ethylbenzene, and Benzene near their Glass Transition Temperatures Investigated using Inert Gas Permeation

    SciTech Connect (OSTI)

    May, Robert A.; Smith, R. Scott; Kay, Bruce D.

    2013-11-21T23:59:59.000Z

    We investigate the mobility of supercooled liquid toluene, ethylbenzene, and benzene near their respective glass transition temperatures (Tg). The permeation rate of Ar, Kr, and Xe through the supercooled liquid created when initially amorphous overlayers heated above their glass transition temperature is used to determine the diffusivity. Amorphous benzene crystallizes at temperatures well below its Tg and as a result the inert gas underlayer remains trapped until the onset of benzene desorption. In contrast, for toluene and ethylbenzene the onset of inert gas permeation is observed at temperatues near Tg. The inert gas desorption peak temperature as a function of the heating rate and overlayer thickness is used to quantify the diffusivity of supercooled liquid toluene and ethylbenzene from 115 K to 135 K. In this temperature range, diffusivities are found to vary across five orders of magnitude (~10-14 to 10-9 cm2/s). These data are compared to viscosity measurements and used to determine the low temperature fractional Stokes-Einstein exponent. Efforts to determine the diffusivity of a mixture of benzene and ethylbenzene are detailed, and the effect of mixing these materials on benzene crystallization is explored using infrared spectroscopy.

  18. Degradative capacities and bioaugmentation potential of an anaerobic benzene-degrading bacterium strain DN11

    SciTech Connect (OSTI)

    Yuki Kasai; Yumiko Kodama; Yoh Takahata; Toshihiro Hoaki; Kazuya Watanabe [Marine Biotechnology Institute, Kamaishi (Japan)

    2007-09-15T23:59:59.000Z

    Azoarcus sp. strain DN11 is a denitrifying bacterium capable of benzene degradation under anaerobic conditions. The present study evaluated strain DN11 for its application to bioaugmentation of benzene-contaminated underground aquifers. Strain DN11 could grow on benzene, toluene, m-xylene, and benzoate as the sole carbon and energy sources under nitrate-reducing conditions, although o- and p-xylenes were transformed in the presence of toluene. Phenol was not utilized under anaerobic conditions. Kinetic analysis of anaerobic benzene degradation estimated its apparent affinity and inhibition constants to be 0.82 and 11 {mu}M, respectively. Benzene-contaminated groundwater taken from a former coal-distillation plant site in Aichi, Japan was anaerobically incubated in laboratory bottles and supplemented with either inorganic nutrients (nitrogen, phosphorus, and nitrate) alone, or the nutrients plus strain DN11, showing that benzene was significantly degraded only when DN11 was introduced. Denaturing gradient gel electrophoresis of PCR-amplified 16S rRNA gene fragments, and quantitative PCR revealed that DN11 decreased after benzene was degraded. Following the decrease in DN11 16S rRNA gene fragments corresponding to bacteria related to Owenweeksia hongkongensis and Pelotomaculum isophthalicum, appeared as strong bands, suggesting possible metabolic interactions in anaerobic benzene degradation. Results suggest that DN11 is potentially useful for degrading benzene that contaminates underground aquifers at relatively low concentrations. 50 refs., 6 figs., 1 tab.

  19. ForReview.Confidential-ACS Catalytic Transformation of 1,3,5 -Trimethyl Benzene over USY Zeolite

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    and trimethylbenzenes (TMB) coming from the reforming and pyrolysis of gasoline, into benzene and xylenes via

  20. Atmos. Chem. Phys., 13, 87978811, 2013 www.atmos-chem-phys.net/13/8797/2013/

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    , acrolein, benzene, toluene and xylenes are also emitted. Positive matrix factorization (PMF) was applied

  1. Exposure Evaluation for Benzene, Lead and Noise in Vehicle and Equipment Repair Shops

    SciTech Connect (OSTI)

    Sweeney, Lynn C.

    2013-04-10T23:59:59.000Z

    An exposure assessment was performed at the equipment and vehicle maintenance repair shops operating at the U. S. Department of Energy Hanford site, in Richland, Washington. The maintenance shops repair and maintain vehicles and equipment used in support of the Hanford cleanup mission. There are three general mechanic shops and one auto body repair shop. The mechanics work on heavy equipment used in construction, cranes, commercial motor vehicles, passenger-type vehicles in addition to air compressors, generators, and farm equipment. Services include part fabrication, installation of equipment, repair and maintenance work in the engine compartment, and tire and brake services. Work performed at the auto body shop includes painting and surface preparation which involves applying body filler and sanding. 8-hour time-weighted-average samples were collected for benzene and noise exposure and task-based samples were collected for lead dust work activities involving painted metal surfaces. Benzene samples were obtained using 3M™ 3520 sampling badges and were analyzed for additional volatile organic compounds. These compounds were selected based on material safety data sheet information for the aerosol products used by the mechanics for each day of sampling. The compounds included acetone, ethyl ether, toluene, xylene, VM&P naphtha, methyl ethyl ketone, and trichloroethylene. Laboratory data for benzene, VM&P naphtha, methyl ethyl ketone and trichloroethylene were all below the reporting detection limit. Airborne concentrations for acetone, ethyl ether, toluene and xylene were all less than 10% of their occupational exposure limit. The task-based samples obtained for lead dusts were submitted for a metal scan analysis to identify other metals that might be present. Laboratory results for lead dusts were all below the reporting detection limit and airborne concentration for the other metals observed in the samples were less than 10% of the occupational exposure limit. Noise dosimetry sampling was performed on a random basis and was representative of the different work activities within the four shops. Twenty three percent of the noise samples exceeded the occupational exposure limit of 85 decibels for an 8-hour time-weightedaverage. Work activities where noise levels were higher included use of impact wrenches and grinding wheels.

  2. Polyfunctional catalyst for processiing benzene fractions

    SciTech Connect (OSTI)

    G. Byakov; B.D. Zubitskii; B.G. Tryasunov; I.Ya. Petrov [Kuznetsk Basin State Technical University, Kemerovo (Russian Federation)

    2009-05-15T23:59:59.000Z

    A by-product of the coke industry is a raw benzene fraction benzene- 1 which may serve as for catalytic processes. The paper reports a study on the influence of the composition and temperatures on the activity and selectivity of NiO-V{sub 2}O{sub 6}-MoO{sub 3}/{gamma}-Al{sub 2}O{sub 3} catalysts and the corresponding binary and tertiary subsystems are studied by a pulse method in model reactions; the hydrodealkylating of toluene and the hydrodesulfurizing of thioprhene. The optimal catalyst composition is established. The new catalyst is compared with industrial catalysts.

  3. Remediation of overlapping benzene/MTBE and MTBE-only plumes: A case study

    SciTech Connect (OSTI)

    Carpenter, P.L. [TolTest, Inc., Pittsburgh, PA (United States); Vinch, C.A. [Ryder Transportation Services, Lawrenceville, NJ (United States)

    1997-12-31T23:59:59.000Z

    Two overlapping dissolved hydrocarbon plumes were identified in the shallow water-bearing zone at a commercial vehicle service and fueling facility. Plume 1 originated from a pre-1993 gasoline product line/dispenser leak. This plume contained a relatively common mix of benzene, toluene, ethylbenzene, xylenes (BTEX), and methyl tert-butyl ether (MTBE); benzene and MTBE were identified as the Plume 1 contaminants of concern based on their detection at approximately 200 {mu}g/l each, which exceeded regulatory guidance. Plume 2, which was detected in the tank cavity during UST removal, resulted from gasoline line leaks/underground storage tank overfills. Although the majority of impacted soils in both the dispenser and tank cavity areas were removed during UST excavation, rainfall during impacted soil removal mobilized the MTBE contained in the soils to groundwater. As a result, Plume 2 contained approximately 900 {mu}g/l MTBE while BTEX compounds were non-detect. Although the impacted zone sustained an approximate yield of only 0.3 gallon per minute, Pennsylvania regulations dictate that this zone must be treated as an aquifer. The failure of remediating gasoline plumes using pump-and-treat has been predominantly due to BTEX`s tendency to adsorb onto soil, creating a residual-phase product layer which acts as a continuing source of dissolved-phase BTEX. Based on this experience, most groundwater and remediation professionals reject pump-and-treat as a viable remedial option, except in situations where controlling groundwater movement is the predominant goal.

  4. Energy Efficiency Improvement and Cost Saving Opportunities for the Petrochemical Industry - An ENERGY STAR(R) Guide for Energy and Plant Managers

    E-Print Network [OSTI]

    Neelis, Maarten

    2008-01-01T23:59:59.000Z

    Ethylene dichloride 1 MTBE 2 Vinylchloride 3 Ethylbenzene 1Methyl- Tertiary-Butyl-Ether (MTBE) or Ethyl-Tertiary-Butyl-Styrene Vinylchloride MTBE Benzene, Toluene, Xylene Acetone

  5. Measurement and Characterization of Unregulated Emissions from...

    Broader source: Energy.gov (indexed) [DOE]

    Diesel PM Polycyclic organic Matter (POM) Formaldehyde Acetaldehyde 1,3-Butadiene Acrolein Benzene Toluene Ethylbenzene Xylene Polycyclic Aromatic Hydrocarbons (PAHs) Diesel...

  6. 1,2,4-Trimethylbenzene Transformation Reaction Compared with its Transalkylation Reaction with Toluene over USY Zeolite Catalyst

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    1,2,4-Trimethylbenzene Transformation Reaction Compared with its Transalkylation Reaction. This shows that toluene would rather accept a methyl group to transform to xylene than lose a methyl group for transformation of TMB. Cejka et al.3 studied the effect of the structure of large-pore zeolites of beta, Y, L

  7. Dissociation of Benzene Dication [C6H6]2+: Exploring the Potential Energy Surface Smriti Anand and H. Bernhard Schlegel*

    E-Print Network [OSTI]

    Schlegel, H. Bernhard

    Dissociation of Benzene Dication [C6H6]2+: Exploring the Potential Energy Surface Smriti Anand The singlet potential energy surface for the dissociation of benzene dication has been explored, and its three such as acetylene, cyclopropane, butadiene, cyclohexane, benzene, toluene, and naphthalene. The Coulomb explosion

  8. Photonic crystal slot waveguide for high sensitivity on-chip near-infrared optical absorption spectroscopy of xylene in water

    E-Print Network [OSTI]

    Chen, Ray

    of ethanol, despite clean air-saturated water flowing continuously through the tank at a relative high Oil & Gas Pollution Control, China University of Petroleum-Beijing, 18 Fuxue Rd., Beijing 102249-occurring or pre-existing toxic aromatic hydro- carbons such as benzene, toluene, ethylbenzene and xy- lenes (BTEX

  9. Mobility of Supercooled liquid Toluene, Ethylbenzene, and Benzene...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    across five orders of magnitude (10-14 to 10-9 cm2s). These data are compared to viscosity measurements and used to determine the low temperature fractional Stokes-Einstein...

  10. TRAFFIC-RELATED AIR POLLUTION. A PILOT EXPOSURE1 ASSESSMENT IN BEIRUT, LEBANON2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    the use of biomarkers of exposure to benzene and BD. Personal benzene, toluene,30 ethylbenzene, and xylene as biomarker of exposure to BD in humans. Traffic policemen, who are exposed to46 hal-00914713,version1-25Jan

  11. Understanding orchestrated chemical reactions in toluene/o-xylene monooxygenase from pseudomonas sporium OX1

    E-Print Network [OSTI]

    Song, Woon Ju

    2011-01-01T23:59:59.000Z

    Chapter 1. Geometric and Functional Versatility of Carboxylate-Bridged Nonheme- Diiron Motifs: sMMO and ToMO. Several metalloenzymes utilize a carboxylate-bridged non-heme diiron motif for dioxygen activation. Despite their ...

  12. Modeling theta-theta Interactions with the Effective Fragment Potential Method: The Benzene Dimer and Substituents

    SciTech Connect (OSTI)

    Toni Smithl; Lyudmila V. Slipchenko; Mark S. Gordon

    2008-02-27T23:59:59.000Z

    This study compares the results of the general effective fragment potential (EFP2) method to the results of a previous combined coupled cluster with single, double, and perturbative triple excitations [CCSD(T)] and symmetry-adapted perturbation theory (SAPT) study [Sinnokrot and Sherrill, J. Am. Chem. Soc., 2004, 126, 7690] on substituent effects in {pi}-{pi} interactions. EFP2 is found to accurately model the binding energies of the benzene-benzene, benzene-phenol, benzene-toluene, benzene-fluorobenzene, and benzene-benzonitrile dimers, as compared with high-level methods [Sinnokrot and Sherrill, J. Am. Chem. Soc., 2004, 126, 7690], but at a fraction of the computational cost of CCSD(T). In addition, an EFP-based Monte Carlo/simulated annealing study was undertaken to examine the potential energy surface of the substituted dimers.

  13. Isobaric vapor-liquid equilibria of p-xylene + o-xylene and m-xylene + o-xylene systems at 6. 66 and 26. 66 kPa

    SciTech Connect (OSTI)

    Llopis, F.J.; Monton, J.B. (Univ. de Valencia (Spain). Dept. de Ingenieria Quimica)

    1994-01-01T23:59:59.000Z

    Vapor-liquid equilibrium data were obtained for systems of o-xylene with p- and m-xylenes at 6.66 and 26.66 kPa. The activity coefficients were found to be thermodynamically consistent. They were equally well correlated with the Margules, Van Laar, Wilson, NRTL, and UNIQUAC equations. The parameters of these equations are given.

  14. Drinking Water Problems: Benzene

    E-Print Network [OSTI]

    Dozier, Monty; Lesikar, Bruce J.

    2009-04-16T23:59:59.000Z

    on their property, live within a half-mile of a gasoline station or petroleum storage or refining facility, or notice a sweet, chemical smell in their water should have their water wells tested for benzene. Benzene attacks the central nervous system; acute ex... of red and white blood cells and platelets. Breathing high levels of benzene for a long time can cause leukemia and/or disruptions of the bone marrow. Long-term exposures also can damage chromosomes, depress the immune system, reduce the size...

  15. Drinking Water Problems: Benzene 

    E-Print Network [OSTI]

    Dozier, Monty; Lesikar, Bruce J.

    2009-04-16T23:59:59.000Z

    Drinking water in Texas sometimes contains potentially harmful chemicals, including benzene. Well owners can learn how to treat their well water to remove these chemicals. 4 pages, 3 images...

  16. Soot precursor measurements in benzene and hexane diffusion flames

    SciTech Connect (OSTI)

    Kobayashi, Y.; Furuhata, T.; Amagai, K.; Arai, M. [Department of Mechanical System Engineering, Graduate School of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu-shi, Gunma 376-8515 (Japan)

    2008-08-15T23:59:59.000Z

    To clarify the mechanism of soot formation in diffusion flames of liquid fuels, measurements of soot and its precursors were carried out. Sooting diffusion flames formed by a small pool combustion equipment system were used for this purpose. Benzene and hexane were used as typical aromatic and paraffin fuels. A laser-induced fluorescence (LIF) method was used to obtain spatial distributions of polycyclic aromatic hydrocarbons (PAHs), which are considered as soot particles. Spatial distributions of soot in test flames were measured by a laser-induced incandescence (LII) method. Soot diameter was estimated from the temporal change of LII intensity. A region of transition from PAHs to soot was defined from the results of LIF and LII. Flame temperatures, PAH species, and soot diameters in this transition region were investigated for both benzene and hexane flames. The results show that though the flame structures of benzene and hexane were different, the temperature in the PAHs-soot transition region of the benzene flame was similar to that of the hexane flame. Furthermore, the relationship between the PAH concentrations measured by gas chromatography in both flames and the PAH distributions obtained from LIF are discussed. It was found that PAHs with smaller molecular mass, such as benzene and toluene, remained in both the PAHs-soot transition and sooting regions, and it is thought that molecules heavier than pyrene are the leading candidates for soot precursor formation. (author)

  17. HCCI experiments with toluene reference fuels modeled by a semidetailed chemical kinetic model

    SciTech Connect (OSTI)

    Andrae, J.C.G. [Department of Chemical Engineering and Technology, Royal Institute of Technology (KTH), SE-100 44 Stockholm (Sweden); Brinck, T. [Department of Physical Chemistry, Royal Institute of Technology (KTH), SE-100 44 Stockholm (Sweden); Kalghatgi, G.T. [Shell Global Solutions (UK), P.O. Box 1, Chester CH1 3SH (United Kingdom)

    2008-12-15T23:59:59.000Z

    A semidetailed mechanism (137 species and 633 reactions) and new experiments in a homogeneous charge compression ignition (HCCI) engine on the autoignition of toluene reference fuels are presented. Skeletal mechanisms for isooctane and n-heptane were added to a detailed toluene submechanism. The model shows generally good agreement with ignition delay times measured in a shock tube and a rapid compression machine and is sensitive to changes in temperature, pressure, and mixture strength. The addition of reactions involving the formation and destruction of benzylperoxide radical was crucial to modeling toluene shock tube data. Laminar burning velocities for benzene and toluene were well predicted by the model after some revision of the high-temperature chemistry. Moreover, laminar burning velocities of a real gasoline at 353 and 500 K could be predicted by the model using a toluene reference fuel as a surrogate. The model also captures the experimentally observed differences in combustion phasing of toluene/n-heptane mixtures, compared to a primary reference fuel of the same research octane number, in HCCI engines as the intake pressure and temperature are changed. For high intake pressures and low intake temperatures, a sensitivity analysis at the moment of maximum heat release rate shows that the consumption of phenoxy radicals is rate-limiting when a toluene/n-heptane fuel is used, which makes this fuel more resistant to autoignition than the primary reference fuel. Typical CPU times encountered in zero-dimensional calculations were on the order of seconds and minutes in laminar flame speed calculations. Cross reactions between benzylperoxy radicals and n-heptane improved the model predictions of shock tube experiments for {phi}=1.0 and temperatures lower than 800 K for an n-heptane/toluene fuel mixture, but cross reactions had no influence on HCCI simulations. (author)

  18. Enhancing P-xylene selectivity during m-xylene transformation using mildly pre-coked ZSM-5 catalyst

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    been investigated in detail by several workers [1-12]. Modifications of ZSM-5 by various compounds have-xylene theoretically obtainable from these aromatic compounds is very much limited by thermodynamics. Consequently

  19. Plasma desorption mass spectrometry of organics at low temperatures

    E-Print Network [OSTI]

    Shirey, Eldon Lynn

    1993-01-01T23:59:59.000Z

    , cyclohexane, cyclohexene, 1,3-cyclohexadiene, benzene, toluene, ortho- xylene, meta-xylene, and para-xylene. PDMS is best carried out on solids; accordingly, the samples were frozen. The experiments were run using a time-of-flight mass spectrometer with a 252...

  20. Quantum chromodynamics quark benzene

    E-Print Network [OSTI]

    Jialun Ping; Chengrong Deng; Fan Wang; T. Goldman

    2007-11-28T23:59:59.000Z

    A six-quark state with the benzene-like structure is proposed and studied based on color string model. The calculation with the quadratic confinement show that such structure has the lowest energy among the various hidden color six-quark structures proposed so far. Its possible effect on $NN$ scattering is discussed.

  1. Attenuation of dilute aromatic hydrocarbon transport by a block copolymer in a compacted vertisol

    E-Print Network [OSTI]

    Akin, James Browning

    2001-01-01T23:59:59.000Z

    with benzene, toluene, ethylbenzene, and xylenes. Leachate from permeameters packed with soil containing more than 1% (wt) polymer had BTEX concentrations below the drinking water standard for 3 or more pore volumes. The findings of this research were applied...

  2. Toluene pyrolysis studies and high temperature reactions of propargyl chloride

    SciTech Connect (OSTI)

    Kern, R.D.; Chen, H.; Qin, Z. [Univ. of New Orleans, LA (United States)

    1993-12-01T23:59:59.000Z

    The main focus of this program is to investigate the thermal decompositions of fuels that play an important role in the pre-particle soot formation process. It has been demonstrated that the condition of maximum soot yield is established when the reaction conditions of temperature and pressure are sufficient to establish a radical pool to support the production of polyaromatic hydrocarbon species and the subsequent formation of soot particles. However, elevated temperatures result in lower soot yields which are attributed to thermolyses of aromatic ring structures and result in the bell-shaped dependence of soot yield on temperature. The authors have selected several acyclic hydrocarbons to evaluate the chemical thermodynamic and kinetic effects attendant to benzene formation. To assess the thermal stability of the aromatic ring, the authors have studied the pyrolyses of benzene, toluene, ethylbenzene, chlorobenzene and pyridine. Time-of-flight mass spectrometry (TOF) is employed to analyze the reaction zone behind reflected shock waves. Reaction time histories of the reactants, products, and intermediates are constructed and mechanisms are formulated to model the experimental data. The TOF work is often performed with use of laser schlieren densitometry (LS) to measure density gradients resulting from the heats of various reactions involved in a particular pyrolytic system. The two techniques, TOF and LS, provide independent and complementary information about ring formation and ring rupture reactions.

  3. Fuel Dependence of Benzene Pathways

    SciTech Connect (OSTI)

    Zhang, H; Eddings, E; Sarofim, A; Westbrook, C

    2008-07-14T23:59:59.000Z

    The relative importance of formation pathways for benzene, an important precursor to soot formation, was determined from the simulation of 22 premixed flames for a wide range of equivalence ratios (1.0 to 3.06), fuels (C{sub 1}-C{sub 12}), and pressures (20 to 760 torr). The maximum benzene concentrations in 15 out of these flames were well reproduced within 30% of the experimental data. Fuel structural properties were found to be critical for benzene production. Cyclohexanes and C{sub 3} and C{sub 4} fuels were found to be among the most productive in benzene formation; and long-chain normal paraffins produce the least amount of benzene. Other properties, such as equivalence ratio and combustion temperatures, were also found to be important in determining the amount of benzene produced in flames. Reaction pathways for benzene formation were examined critically in four premixed flames of structurally different fuels of acetylene, n-decane, butadiene, and cyclohexane. Reactions involving precursors, such as C{sub 3} and C{sub 4} species, were examined. Combination reactions of C{sub 3} species were identified to be the major benzene formation routes with the exception of the cyclohexane flame, in which benzene is formed exclusively from cascading fuel dehydrogenation via cyclohexene and cyclohexadiene intermediates. Acetylene addition makes a minor contribution to benzene formation, except in the butadiene flame where C{sub 4}H{sub 5} radicals are produced directly from the fuel, and in the n-decane flame where C{sub 4}H{sub 5} radicals are produced from large alkyl radical decomposition and H atom abstraction from the resulting large olefins.

  4. Dioxygen activation and substrate hydroxylation by the hydroxylase component of toluene/O-xylene monooxygenase from pseudomonas sporium OX1

    E-Print Network [OSTI]

    Murray, Leslie Justin

    2007-01-01T23:59:59.000Z

    Non-heme carboxylate-bridged diiron centers in the hydroxylase components of the bacterial multicomponent monooxygenases activate dioxygen at structurally homologous active sites. Catalysis requires the management of four ...

  5. Baytown Xylene Fractionation Energy Reduction using Dynamic Matrix Control (DMC)

    E-Print Network [OSTI]

    Hokanson, D.

    2014-01-01T23:59:59.000Z

    Technology Conference New Orleans, LA. May 20-23, 2014 2Outline • Baytown Chemical Complex • Xylene Fractionation Overview • Dynamic Matrix Control • Results • Benefits/Wrap-Up ESL-IE-14-05-33 Proceedings of the Thrity-Sixth Industrial Energy Technology... Conference New Orleans, LA. May 20-23, 2014 3Baytown Chemical / Refining Complex ExxonMobil Baytown Refining & Chemical Complex • One of world’s largest integrated, most technologically advanced petroleum/petrochemical complexes, in operation since 1919...

  6. Collision lifetimes of polyatomic molecules at low temperatures: Benzene–benzene vs benzene–rare gas atom collisions

    SciTech Connect (OSTI)

    Cui, Jie; Krems, Roman V. [Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1 (Canada); Li, Zhiying [Department of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States)

    2014-10-28T23:59:59.000Z

    We use classical trajectory calculations to study the effects of the interaction strength and the geometry of rigid polyatomic molecules on the formation of long-lived collision complexes at low collision energies. We first compare the results of the calculations for collisions of benzene molecules with rare gas atoms He, Ne, Ar, Kr, and Xe. The comparison illustrates that the mean lifetimes of the collision complexes increase monotonically with the strength of the atom–molecule interaction. We then compare the results of the atom–benzene calculations with those for benzene–benzene collisions. The comparison illustrates that the mean lifetimes of the benzene–benzene collision complexes are significantly reduced due to non-ergodic effects prohibiting the molecules from sampling the entire configuration space. We find that the thermally averaged lifetimes of the benzene–benzene collisions are much shorter than those for Xe with benzene and similar to those for Ne with benzene.

  7. Process for the preparation of ethyl benzene

    DOE Patents [OSTI]

    Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

    1995-12-19T23:59:59.000Z

    Ethyl benzene is produced in a catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 50 C to 300 C, using as the catalyst a mole sieve characterized as acidic by feeding ethylene to the catalyst bed while benzene is conveniently added through the reflux to result in a molar excess present in the reactor to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene and diethyl benzene in the bottoms. The bottoms are fractionated, the ethyl benzene recovered and the bottoms are contacted with benzene in the liquid phase in a fixed bed straight pass reactor under conditions to transalkylate the benzene thereby converting most of the diethyl benzene to ethyl benzene which is again separated and recovered. 2 figs.

  8. Process for the preparation of ethyl benzene

    DOE Patents [OSTI]

    Smith, Jr., Lawrence A. (Houston, TX); Arganbright, Robert P. (Houston, TX); Hearn, Dennis (Houston, TX)

    1995-01-01T23:59:59.000Z

    Ethyl benzene is produced in a catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 50.degree. C. to 300.degree. C., using as the catalyst a mole sieve characterized as acidic by feeding ethylene to the catalyst bed while benzene is conveniently added through the reflux to result in a molar excess present in the reactor to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene and diethyl benzene in the bottoms. The bottoms are fractionated, the ethyl benzene recovered and the bottoms are contacted with benzene in the liquid phase in a fixed bed straight pass reactor under conditions to transalkylate the benzene thereby converting most of the diethyl benzene to ethyl benzene which is again separated and recovered.

  9. Modeling Xylene Reactions over ZSM-5 Zeolite in a Riser Simulator: 1,3 versus 1,2-Methyl Shift

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    -xylene p-xylene). The rate constants and activation energies are obtained from simplified kinetic models include solvent use, manufacture of di- paraxylene and herbicides. Total U.S. consumption of p

  10. Interphase Cytogenetics of Workers Exposed to Benzene

    E-Print Network [OSTI]

    California at Berkeley, University of

    Interphase Cytogenetics of Workers Exposed to Benzene Luoping Zhang,1 Nathaniel Rothman,2 Yunxia has been used to demonstrate that the benzene metabolites hydroquinone and 1,2,4-benzenetriol induce FISH procedure to perform cytogenetic analyses on the blood cells of 43 workers exposed to benzene

  11. Xylene Transformation over USY Zeolite: An Experimental and Kinetic Study Iliyas, A. and Al-Khattaf, S.*

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    Xylene Transformation over USY Zeolite: An Experimental and Kinetic Study Iliyas, A. and Al, and reactant type) on the selectivity of xylene transformation has been carried out over USY zeolite. Initial, mechanistic kinetic models, developed from the transformation of each xylene isomers. The parameters optimized

  12. Assessment of BTX Concentrations Near a Petrol Station Using Diffusive Samplers

    E-Print Network [OSTI]

    Boyer, Edmond

    Assessment of BTX Concentrations Near a Petrol Station Using Diffusive Samplers Norbert GONZALEZ to concentration levels of benzene, toluene and xylenes (BTX) at three different levels of proximity to a petrol polluted area. Keywords: Air quality, population exposure, benzene, service Station, petrol, vapour

  13. Xylenes Reactions and Diffusions in ZSM-5 Zeolite based Catalyst S. Al-Khattaf*

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    a great challenge to both the academic field and petrochemical industry. However, the introduction of ZSM-5 for xylene transformation process by Mobil workers in the early 1970s represented a clear

  14. Products of the Benzene + O(3P) Reaction

    E-Print Network [OSTI]

    Osborn, David L.

    2010-01-01T23:59:59.000Z

    Chemistry Products of the Benzene + O( 3 P) Reaction CraigThe gas-phase reaction of benzene with O( 3 P) is ofthe addition of the O atom to benzene, forming an initial

  15. Isobaric vapor-liquid equilibria of ethylbenzene + m-xylene and ethylbenzene + o-xylene systems at 6. 66 and 26. 66 kPa

    SciTech Connect (OSTI)

    Monton, J.B.; Llopis, F.J. (Univ. de Valencia (Spain). Dept. de Ingenieria Quimica)

    1994-01-01T23:59:59.000Z

    Vapor-liquid equilibrium data were obtained for systems of ethylbenzene with m- and o-xylenes at 6.66 and 26.66 kPa. The activity coefficients were found to be thermodynamically consistent. They were equally well correlated with the Margules, Van Laar, Wilson, NRTL, and UNIQUAC equations. The parameters of these equations are given.

  16. ON THE PURPORTED FISCHER-TROPSCH ALKYLATION OF BENZENE: THE REACTION OF BENZENE WITH ALUMINUM TRICHLORIDE REVISITED

    E-Print Network [OSTI]

    Benner, Linda S.

    2014-01-01T23:59:59.000Z

    ON THE PURPORTED FISCHER-TROPSCH ALKYLATION OF BENZENE: THEOn the Purported Fischer-Tropsch Alkylation of Benzene: TheAbstract The purported Fischer-Tropsch alkylation of benzene

  17. Benzene Dimer: Dynamic Structure and Thermodynamics Derived from...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Benzene Dimer: Dynamic Structure and Thermodynamics Derived from On-the-Fly ab initio DFT-D Molecular Dynamic Simulations. Benzene Dimer: Dynamic Structure and Thermodynamics...

  18. Development of Probabilistic Emission Inventories of Benzene, Formaldehyde

    E-Print Network [OSTI]

    Frey, H. Christopher

    Development of Probabilistic Emission Inventories of Benzene, Formaldehyde And Chromium emission inventories (EI) of benzene, formaldehyde and chromium for the Houston area. This project

  19. Comparative Investigation of Benzene Steam Reforming over Spinel...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Investigation of Benzene Steam Reforming over Spinel Supported Rh and Ir Catalysts. Comparative Investigation of Benzene Steam Reforming over Spinel Supported Rh and Ir Catalysts....

  20. LIGHT SCATTERING SPECTROSCOPY OF PULYDIMETHYLSILOXANE-TOLUENE GELS

    E-Print Network [OSTI]

    Boyer, Edmond

    1499 LIGHT SCATTERING SPECTROSCOPY OF PULYDIMETHYLSILOXANE-TOLUENE GELS J. P. MUNCH, P. LEMARÉCHAL varie avec la concentration en polymère selon une loi de puissance avec un exposant plus élevé que celui- siloxane-toluene gels formed either by swelling permanent networks or by dissolving linear macro- molecules

  1. Benzene Dimer DOI: 10.1002/anie.201300653

    E-Print Network [OSTI]

    Benzene Dimer DOI: 10.1002/anie.201300653 Structure of the Benzene Dimer--Governed by Dynamics van der Avoird* The benzene dimer is a prototypical system for studying noncovalent interactions in the structure and dynamic behavior of proteins and DNA. The first (1975) experimental study of the benzene dimer

  2. Original article 789 Genetic polymorphisms and benzene metabolism in humans

    E-Print Network [OSTI]

    California at Berkeley, University of

    Original article 789 Genetic polymorphisms and benzene metabolism in humans exposed to a wide Range on levels of benzene metabolites in 250 benzene-exposed and 136 control workers in Tianjin, China (for all, catechol, and hydroquinone) and nine polymorphisms in seven genes coding for key enzymes in benzene

  3. Formation and distribution of benzene on Titan V. Vuitton,1

    E-Print Network [OSTI]

    Yelle, Roger V.

    Formation and distribution of benzene on Titan V. Vuitton,1 R. V. Yelle,1 and J. Cui1 Received 29 a study of the formation and distribution of benzene (C6H6) on Titan. Analysis of the Cassini Mass Spectrometer (INMS) measurements of benzene densities on 12 Titan passes shows that the benzene signal exhibits

  4. Methods for the synthesis and polymerization of .alpha.,.alpha.'-dihalo-p-xylenes

    DOE Patents [OSTI]

    Ferraris, John P. (Coppell, TX); Neef, Charles J. (Garland, TX)

    2002-07-30T23:59:59.000Z

    The present invention describes an improved method for the polymerization of .alpha.,.alpha.-dihalo-p-xylene's such as the .alpha.,.alpha.'-dihalo-2-methoxy-5-(2-ethylhexyloxy)-xylene's. The procedure for synthesis is based on the specific order of addition of reagents and the use of an anionic initiator that allows control of the molecular weight of the polymer. The molecular weight control allows processability of the polymer which is important for its utility in applications including in light-emitting-diodes, field effect transistors and photovoltaic devices.

  5. Protein Adducts of 1,4-Benzoquinone and Benzene Oxide among Smokers and Nonsmokers Exposed to Benzene in China1

    E-Print Network [OSTI]

    California at Berkeley, University of

    Protein Adducts of 1,4-Benzoquinone and Benzene Oxide among Smokers and Nonsmokers Exposed to Benzene in China1 Karen Yeowell-O'Connell, Nathaniel Rothman, Suramya Waidyanatha, Martyn T. Smith [W. E. B.] Abstract Hemoglobin (Hb) and albumin (Alb) adducts of the benzene metabolites benzene

  6. Benzene waste NESHAP update and requirements

    SciTech Connect (OSTI)

    Bennett, C.D. (Ashland Petroleum Co., Russell, KY (United States))

    1993-01-01T23:59:59.000Z

    On January 7, 1993, USEPA promulgated the clarified National Emission Standard for Hazardous Air Pollutants (NESHAP) for Benzene Waste Operations, 40 CFR 61 Subpart FF. This rule limits benzene emissions from petroleum refinery wastewater systems and other waste management units. Since the time of initial promulgation, March 7, 1990, EPA admits that there has been widespread confusion among refiners concerning the key provisions of the rule. This paper provides clarifications of the new final rule and an overview of both the new alternative compliance options and the compliance waiver provisions.

  7. Pilot-Scale Benzene Retention and Release Demonstration

    SciTech Connect (OSTI)

    Marek, J.C.

    2003-11-10T23:59:59.000Z

    During the initial months of In-Tank Precipitation radioactive operation in 1995 the process experienced high rates of tetraphenylborate decomposition with assumed corresponding high rates of benzene generation. In March 1996 after a two month quiescent period, a water addition to Tank 48H resulted in an unexpected benzene release to the tank vapor phase. This was the first time a low energy input resulted in a significant release rate. This led to questions about how benzene, generated in-situ by TPB decomposition, was retained in the surrounding potassium tetraphenylborate slurry. It was postulated the retention mechanism may have changed during the quiescent period prior to March so the benzene present became readily releasable to the vapor phase with low energy input to the slurry or that enough benzene accumulated that some of it was in a different, more releasable form. Readily releasable is a qualitative term defined as a rapid release of benzene at a rate approaching evaporation of a free benzene layer. It is intended to distinguish between benzene in a form with high liquid phase resistance to mass transfer diffusion controlled from benzene in a form with minimal liquid phase resistance to mass transfer free benzene layer evaporation. If a readily releasable form of benzene was present, the vapor space profile during release tests was anticipated to have an initial benzene vapor space concentration peak followed by a lower vapor concentration, longer duration release.

  8. Modeling Human Metabolism of Benzene Following Occupational and Environmental Exposures

    E-Print Network [OSTI]

    California at Berkeley, University of

    Modeling Human Metabolism of Benzene Following Occupational and Environmental Exposures Sungkyoon) models to investigate nonlinear relationships between levels of benzene metabolites (E,E- muconic acid, S-phenylmercapturic acid, phenol, hydroqui- none, and catechol) and benzene exposure among 386 exposed and control workers

  9. BIOMARKERS IN THE MOLECULAR EPIDEMIOLOGY OF BENZENE-EXPOSED WORKERS

    E-Print Network [OSTI]

    California at Berkeley, University of

    BIOMARKERS IN THE MOLECULAR EPIDEMIOLOGY OF BENZENE-EXPOSED WORKERS Martyn T. Smith Division from workers exposed to high levels of benzene. The goal of these studies is to develop and validate (1) biomarkers of exposure to benzene, such as albumin or hemoglobin adducts; (2) molecular markers

  10. Products of the Benzene + O(3 P) Reaction

    E-Print Network [OSTI]

    Krylov, Anna I.

    Products of the Benzene + O(3 P) Reaction Craig A. Taatjes,*, David L. Osborn, Talitha M. Selby ReceiVed: January 7, 2010 The gas-phase reaction of benzene with O(3 P) is of considerable interest mainly through the addition of the O atom to benzene, forming an initial triplet diradical adduct, which

  11. Molecular dynamics of liquid benzene via femtosecond pulses laser excitation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1749 Molecular dynamics of liquid benzene via femtosecond pulses laser excitation J. Etchepare, G moléculaires. Abstract. 2014 We analyse the complex response of liquid benzene to the applied 45 fs FHWM new results obtained by the transient grating temporal behaviour analysis of benzene, a molecule

  12. Statement for the Committee on Health, Education, Labor, and Pensions United States Senate June 15, 2010

    E-Print Network [OSTI]

    Bandettini, Peter A.

    and exposed communities, and a report on NIEHS's early and ongoing role in helping to protect oil spill and more toxic components, such as benzene, toluene, and xylene. These and other volatile organic compounds effects such as cancer, birth defects, and neurological effects. Oil that has been exposed to air

  13. Statement for the Energy and Commerce Committee Subcommittee on Health United States House of Representatives

    E-Print Network [OSTI]

    Bandettini, Peter A.

    and exposed communities, and a report on NIEHS's early and ongoing role in helping to protect oil spill and more toxic components, such as benzene, toluene, and xylene. These and other volatile organic compounds effects such as cancer, birth defects, and neurological effects. Oil that has been exposed to air

  14. Review Paper/ Crude Oil at the Bemidji Site: 25 Years of

    E-Print Network [OSTI]

    and water flow, vapor diffusion, and the progression of biodegradation. Pore-scale capillary pressure large residual oil saturations. Hydrocarbon attenuation and plume extent was a function of groundwater of ground- water contamination by benzene, toluene, ethylbenzene, and xylenes (BTEX) (Council

  15. Liquid-liquid equilibria for ternary systems containing hydrocarbons and propylene carbonate

    SciTech Connect (OSTI)

    Annesini, M.C.; Gironi, F.; Marrelli, L.

    1985-04-01T23:59:59.000Z

    Experimental data of liquid-liquid equillibrium at 20/sup 0/C are reported for six ternary systems containing propylene carbonate with n-hexane-benzene, n-hexane-ethylbenzene, n-heptane-toluene, n-heptane-ethylbenzene, n-octane-o-xylene, and n-octane-ethylbenzene. The data are correlated by means of NRTL and UNIQUAC models and relative parameters are given.

  16. EuropeanCommunities,2007 First results from the new JRC greenhouse gas monitoring site at Ispra, Italy

    E-Print Network [OSTI]

    ) and the biomass burning tracer acetonitrile. Additional air quality measurements (e.g. carbon monoxide, N2O, CO and the biomass burning tracer acetonitrile (CH3CN) during the 2007/08 winter we are able on acetonitrile as a tracer for biofuel burning emissions and benzene, toluene, and xylenes as tracers for fossil

  17. Nonlinear diffusion in Acetone-Benzene Solution

    E-Print Network [OSTI]

    Obukhovsky, Vjacheslav V

    2010-01-01T23:59:59.000Z

    The nonlinear diffusion in multicomponent liquids under chemical reactions influence has been studied. The theory is applied to the analysis of mass transfer in a solution of acetone-benzene. It has been shown, that the creation of molecular complexes should be taken into account for the explanation of the experimental data on concentration dependence of diffusion coefficients. The matrix of mutual diffusivities has been found and effective parameters of the system have been computed.

  18. Catalytic Transformation of Toluene over High Acidity Y-Zeolite Based S. Al-Khattaf*

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    Catalytic Transformation of Toluene over High Acidity Y-Zeolite Based Catalyst S. Al Abstract Catalytic transformation of toluene has been investigated over Y-zeolite based catalysts in the temperature range of 400-500o C to understand the transformation of toluene over high acidity Y-based zeolite

  19. Continuous Operation of Foamed Emulsion Bioreactors Treating Toluene Vapors

    E-Print Network [OSTI]

    Continuous Operation of Foamed Emulsion Bioreactors Treating Toluene Vapors Eunsung Kan, Marc A.interscience.wiley.com). DOI: 10.1002/bit.20619 Abstract: Continuous operation of a new bioreactor for air pollution control called the foamed emulsion bioreactor (FEBR) has been investigated. The effect of several liquid feeding

  20. The determination of area source emission factors using whole air sampling

    E-Print Network [OSTI]

    Shannon, Harriet Patricia

    1992-01-01T23:59:59.000Z

    , Tedlar bags have been shown to be transparent to ground level radiation . They are also 18 difficult to clean and are subject to sample loss through permeation . Studies have shown that toluene and xylenes 14 show an appreciable loss if exposed... rates from a land treatment facility. The observed solvent concentrations ranged from 3. 2, to 0. 1 gg/m for benzene, 5. 0 to 1. 1 ug/m for toluene, and 9. 2 3 3 to 0. 7 pg/m for xylene. Monitoring results were compared 3 to concentrations predicted...

  1. Benzene-derived N2-(4-hydroxyphenyl)-deoxyguanosine adduct: UvrABC incision and its conformation in DNA

    E-Print Network [OSTI]

    Hang, Bo

    2010-01-01T23:59:59.000Z

    in a historical UK cohort of benzene exposed workers. OccupEnvironmental exposure to benzene: an update. Environ Health2004. Genotoxicity of benzene and its metabolites. Mutat Res

  2. Resonant ion-dip infrared spectroscopy of the S4 and D2d water octamers in benzene-,,water...8 and benzene2-,,water...8

    E-Print Network [OSTI]

    Zwier, Timothy S.

    Resonant ion-dip infrared spectroscopy of the S4 and D2d water octamers in benzene-,,water...8 and benzene2-,,water...8 Christopher J. Gruenloh, Joel R. Carney, Fredrick C. Hagemeister, Caleb A. Arrington the hydrogen-bonding topologies of two isomers each of the benzene- water)8 and (benzene 2 water)8 gas

  3. 28 VOLUME 115 | NUMBER 1 | January 2007 Environmental Health Perspectives Benzene is a ubiquitous environmental conta-

    E-Print Network [OSTI]

    California at Berkeley, University of

    28 VOLUME 115 | NUMBER 1 | January 2007 · Environmental Health Perspectives Research Benzene matter, including cigarette smoking. Air concentra- tions of benzene are typically environments but can exceed 10 ppm in industrial settings where benzene- containing products are used

  4. ENVIRONMENTAL BENZENE EXPOSURE ASSESSMENT FOR PARENT-CHILD PAIRS IN ROUEN, FRANCE

    E-Print Network [OSTI]

    Boyer, Edmond

    1 ENVIRONMENTAL BENZENE EXPOSURE ASSESSMENT FOR PARENT-CHILD PAIRS IN ROUEN, FRANCE Amin KOUNIALIa environmental benzene exposure. In this study we compared personal benzene exposure and inhalation uptake in a group of children to those of their parents. We also compared levels of urinary benzene metabolites

  5. Modeling the Pi-electrons of Benzene as Particles in a Ring Frank Rioux

    E-Print Network [OSTI]

    Rioux, Frank

    Modeling the Pi-electrons of Benzene as Particles in a Ring Frank Rioux In this exercise benzene circumference is approximated as six benzene carbon-carbon bond lengths. h 6.6260755 10 34 joule sec c 2 in the ultraviolet just outside the visible range of the electromagnetic spectrum and benzene is a colorless liquid

  6. Phenol-benzene complexation dynamics: Quantum chemistry calculation, molecular dynamics simulations, and two dimensional IR spectroscopy

    E-Print Network [OSTI]

    Fayer, Michael D.

    Phenol-benzene complexation dynamics: Quantum chemistry calculation, molecular dynamics simulations the nature and dynamics of the phenol-benzene complex in the mixed solvent, benzene/CCl4. Under thermal used for the phenol-benzene interaction in the MD simulations is in good accord with the highest level

  7. The water-benzene interaction: Insight from electronic structure theories Jie Ma,1,2,3

    E-Print Network [OSTI]

    Alfè, Dario

    The water-benzene interaction: Insight from electronic structure theories Jie Ma,1,2,3 Dario Alfè,2 theories is challenging. Here we assess the ability of a variety of theories to describe a water-benzene- tween water and benzene. Water benzene is an interesting model system because it is a reasonably small

  8. Benzene quadrupolarity and arene-arene interactions Zhengyu Wu and Rainer Glaser*

    E-Print Network [OSTI]

    Glaser, Rainer

    1 Benzene quadrupolarity and arene-arene interactions Zhengyu Wu and Rainer Glaser* Department in employing benzenes as lateral synthons in crystal engineering. We recently synthesized a series of perfectly organic NLO crystals. The benzene-benzene T-contact plays a critical role in stabilizing the crystal

  9. Hydrology Days 2014 Thermally Enhanced Attenuation of Substituted Benzenes

    E-Print Network [OSTI]

    at temperatures ranging from 10°C to 30°C, and biogas production has been monitored. Thus far, substituted benzene microcosms have produced less biogas than previous petroleum microcosm studies. This suggests

  10. Quantitative Measurement of Integrated Band Intensities of Benzene...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    cm-1. The spectra were recorded at a resolution of 0.112 cm-1 using a commercial Fourier transform spectrometer. The pressure of each benzene vapor sample was measured using...

  11. Atmosphere-Water Interaction of Chloroform, Toluene, and MTBE in Small Perennial Urban Streams

    E-Print Network [OSTI]

    Atmosphere-Water Interaction of Chloroform, Toluene, and MTBE in Small Perennial Urban Streams-butyl ether (MTBE) are frequently detected VOCs in the atmosphere, surface water, and ground water in urban not be the predominant source of chloroform and toluene in the two urban streams. In contrast, MTBE may be coming from

  12. Intermolecular CH bond activation of benzene and pyridines by a vanadium(III) alkylidene including a stepwise conversion of benzene to

    E-Print Network [OSTI]

    McQuade, D. Tyler

    Intermolecular C­H bond activation of benzene and pyridines by a vanadium(III) alkylidene including a stepwise conversion of benzene to a vanadium-benzyne complex Jose G. Andino,a Uriah J. Kilgore,a Maren Pink of benzene and pyridine is observed with (PNP)V(CH2tBu)2 (1), and in the case of benzene, the formation

  13. One-Photon Mass-Analyzed Threshold Ionization Spectroscopy of Bis(6-benzene)chromium and Its Benzene and Ar Clusters

    E-Print Network [OSTI]

    Kim, Sang Kyu

    One-Photon Mass-Analyzed Threshold Ionization Spectroscopy of Bis(6-benzene)chromium and Its Benzene and Ar Clusters Kyo-Won Choi and Sang Kyu Kim* Department of Chemistry and School of Molecular-analyzed threshold ionization (MATI) spectroscopy of bis(6-benzene)chromium is reported. The adiabatic ionization

  14. Microbial degradation of toluene under sulfate-reducing conditions and the influence of iron on the process

    SciTech Connect (OSTI)

    Beller, H.R.; Grbic-Galic, D.; Reinhard, M.

    1992-01-01T23:59:59.000Z

    Toluene degradation occurred concomitantly with sulfate reduction in anaerobic microcosms inoculated with contaminated subsurface soil from an aviation fuel storage facility near the Patuxent River (Md.). Similar results were obtained from enrichment cultures in which toluene was the sole carbon source. Several lines of evidence suggest that toluene degradation was directly coupled to sulfate reduction in Patuxent River microcosms and enrichment cultures: (1) the two processes were synchronous and highly correlated, (2) the observed stoichiometric ratios of moles of sulfate consumed per mole of toluene consumed were consistent with the theoretical ratio for the oxidation of toluene to CO2 coupled with the reduction of sulfate to hydrogen sulfide, and (3) toluene degradation ceased when sulfate was depleted, and conversely, sulfate reduction ceased when toluene was depleted. Mineralization of toluene was confirmed in experiments with (ring-U-14C)toluene. The addition of millimolar concentrations of amorphous Fe(OH)3 to Patuxent River microcosms and enrichment cultures either greatly facilitated the onset of toluene degradation or accelerated the rate once degradation had begun. In iron-amended microcosms and enrichment cultures, ferric iron reduction proceeded concurrently with toluene degradation and sulfate reduction. Stoichiometric data and other observations indicate that ferric iron reduction was not directly coupled to toluene oxidation but was a secondary, presumably abiotic, reaction between ferric iron and biogenic hydrogen sulfide. (Copyright (c) 1992, American Society for Microbiology.)

  15. Microbial degradation of toluene under sulfate-reducing conditions and the influence of iron on the process

    SciTech Connect (OSTI)

    Beller, H.R.; Grbic-Galic, D.; Reinhard, M. (Stanford Univ., CA (United States))

    1992-03-01T23:59:59.000Z

    Toluene degradation occurred concomitantly with sulfate reduction in anaerobic microcosms inoculated with contaminated subsurface soil from an aviation fuel storage facility near the Patuxent River (Md.). Similar results were obtained for enrichment cultures in which toluene was the sole carbon source. Several lines of evidence suggest that toluene degradation was directly coupled to sulfate reduction in Patuxent River microcosms and enrichment cultures: (1) the two processes were synchronous and highly correlated, (2) the observed stoichiometric ratios of moles of sulfate consumed per mole of toluene consumed were consistent with the theoretical ratio for the oxidation of toluene to CO{sub 2} coupled with the reduction of sulfate to hydrogen sulfide, and (3) toluene degradation ceased when sulfate was depleted, and conversely, sulfate reduction ceased when toluene was depleted. Mineralization of toluene was confirmed in experiments with (ring-U-{sup 14}C)toluene. The addition of millimolar concentrations of amorphous Fe(OH){sub 3} to Patuxent River microcosms and enrichment cultures either greatly facilitated the onset of toluene degradation or accelerated the rate once degradation had begun. In iron-amended microcosms and enrichment cultures, ferric iron reduction proceeded concurrently with toluene degradation and sulfate reduction. Stoichiometric data and other observations indicate that ferric iron reduction was not directly coupled to toluene oxidation but was a secondary, presumably abiotic, reaction between ferric iron and biogenic hydrogen sulfide.

  16. SYNTHESIS OF THE FULLY PROTECTED PHOSPHORAMIDITE OF THE BENZENE-DNA ADDUCT, N2- (4-HYDROXYPHENYL)-2'-DEOXYGUANOSINE AND INCORPORATION OF THE LATER INTO DNA OLIGOMERS

    E-Print Network [OSTI]

    Huang, Bo

    2008-01-01T23:59:59.000Z

    associated with low-level benzene exposure. EpidemiologyC. C. An overview of benzene metabolism. Environ. Healthstudies of human exposure to benzene in China and Europe An

  17. Products of the Benzene + O(3P) Reaction

    SciTech Connect (OSTI)

    Taatjes, Craig A.; Osborn, David L.; Selby, Talitha M.; Meloni, Giovanni; Trevitt, Adam J.; Epifanovsky, Evgeny; Krylov, Anna I.; Sirjean, Baptiste; Dames, Enoch; Wang, Hai

    2010-01-01T23:59:59.000Z

    The gas-phase reaction of benzene with O(3P) is of considerable interest for modeling of aromatic oxidation, and also because there exist fundamental questions concerning the prominence of intersystem crossing in the reaction. While its overall rate constant has been studied extensively, there are still significant uncertainties in the product distribution. The reaction proceeds mainly through the addition of the O atom to benzene, forming an initial triplet diradical adduct, which can either dissociate to form the phenoxy radical and H atom or undergo intersystem crossing onto a singlet surface, followed by a multiplicity of internal isomerizations, leading to several possible reaction products. In this work, we examined the product branching ratios of the reaction between benzene and O(3P) over the temperature range 300?1000 K and pressure range 1?10 Torr. The reactions were initiated by pulsed-laser photolysis of NO2 in the presence of benzene and helium buffer in a slow-flow reactor, and reaction products were identified by using the multiplexed chemical kinetics photoionization mass spectrometer operating at the Advanced Light Source (ALS) of Lawrence Berkeley National Laboratory. Phenol and phenoxy radical were detected and quantified. Cyclopentadiene and cyclopentadienyl radical were directly identified for the first time. Finally, ab initio calculations and master equation/RRKM modeling were used to reproduce the experimental branching ratios, yielding pressure-dependent rate expressions for the reaction channels, including phenoxy + H, phenol, cyclopentadiene + CO, which are proposed for kinetic modeling of benzene oxidation.

  18. Products of the Benzene + O(3P) Reaction

    SciTech Connect (OSTI)

    Taatjes, Craig A.; Osborn, David L.; Selby, Talitha M.; Meloni, Giovanni; Trevitt, Adam J.; Epifanovsky, Evgeny; Krylov, Anna I.; Sirjean, Baptiste; Dames, Enoch; Wang, Hai

    2009-12-21T23:59:59.000Z

    The gas-phase reaction of benzene with O(3P) is of considerable interest for modeling of aromatic oxidation, and also because there exist fundamental questions concerning the prominence of intersystem crossing in the reaction. While its overall rate constant has been studied extensively, there are still significant uncertainties in the product distribution. The reaction proceeds mainly through the addition of the O atom to benzene, forming an initial triplet diradical adduct, which can either dissociate to form the phenoxy radical and H atom, or undergo intersystem crossing onto a singlet surface, followed by a multiplicity of internal isomerizations, leading to several possible reaction products. In this work, we examined the product branching ratios of the reaction between benzene and O(3P) over the temperature range of 300 to 1000 K and pressure range of 1 to 10 Torr. The reactions were initiated by pulsed-laser photolysis of NO2 in the presence of benzene and helium buffer in a slow-flow reactor, and reaction products were identified by using the multiplexed chemical kinetics photoionization mass spectrometer operating at the Advanced Light Source (ALS) of Lawrence Berkeley National Laboratory. Phenol and phenoxy radical were detected and quantified. Cyclopentadiene and cyclopentadienyl radical were directly identified for the first time. Finally, ab initio calculations and master equation/RRKM modeling were used to reproduce the experimental branching ratios, yielding pressure-dependent rate expressions for the reaction channels, including phenoxy + H, phenol, cyclopentadiene + CO, which are proposed for kinetic modeling of benzene oxidation.

  19. Autoignition of toluene reference fuels at high pressures modeled with detailed chemical kinetics

    SciTech Connect (OSTI)

    Andrae, J.C.G. [Department of Chemical Engineering and Technology, Royal Institute of Technology, SE-100 44 Stockholm (Sweden); Shell Global Solutions, P.O. Box 1, Chester CH1 3SH (United Kingdom); Bjoernbom, P. [Department of Chemical Engineering and Technology, Royal Institute of Technology, SE-100 44 Stockholm (Sweden); Cracknell, R.F.; Kalghatgi, G.T. [Shell Global Solutions, P.O. Box 1, Chester CH1 3SH (United Kingdom)

    2007-04-15T23:59:59.000Z

    A detailed chemical kinetic model for the autoignition of toluene reference fuels (TRF) is presented. The toluene submechanism added to the Lawrence Livermore Primary Reference Fuel (PRF) mechanism was developed using recent shock tube autoignition delay time data under conditions relevant to HCCI combustion. For two-component fuels the model was validated against recent high-pressure shock tube autoignition delay time data for a mixture consisting of 35% n-heptane and 65% toluene by liquid volume. Important features of the autoignition of the mixture proved to be cross-acceleration effects, where hydroperoxy radicals produced during n-heptane oxidation dramatically increased the oxidation rate of toluene compared to the case when toluene alone was oxidized. Rate constants for the reaction of benzyl and hydroperoxyl radicals previously used in the modeling of the oxidation of toluene alone were untenably high for modeling of the mixture. To model both systems it was found necessary to use a lower rate and introduce an additional branching route in the reaction between benzyl radicals and O{sub 2}. Good agreement between experiments and predictions was found when the model was validated against shock tube autoignition delay data for gasoline surrogate fuels consisting of mixtures of 63-69% isooctane, 14-20% toluene, and 17% n-heptane by liquid volume. Cross reactions such as hydrogen abstractions between toluene and alkyl and alkylperoxy radicals and between the PRF were introduced for completion of chemical description. They were only of small importance for modeling autoignition delays from shock tube experiments, even at low temperatures. A single-zone engine model was used to evaluate how well the validated mechanism could capture autoignition behavior of toluene reference fuels in a homogeneous charge compression ignition (HCCI) engine. The model could qualitatively predict the experiments, except in the case with boosted intake pressure, where the initial temperature had to be increased significantly in order to predict the point of autoignition. (author)

  20. Changes in the peripheral blood transcriptome associated with occupational benzene exposure identified by cross-comparison on two microarray platforms

    E-Print Network [OSTI]

    Ajo-Franklin, Jonathan

    Changes in the peripheral blood transcriptome associated with occupational benzene exposure Available online 20 January 2009 Keywords: Benzene exposure Gene expression Human blood Toxicogenomics expression changes associated with well-characterized occupational benzene exposure in the peripheral blood

  1. THE JOURNAL OF CHEMICAL PHYSICS 134, 134701 (2011) Binding of hydrogen on benzene, coronene, and graphene from quantum

    E-Print Network [OSTI]

    Alfè, Dario

    2011-01-01T23:59:59.000Z

    THE JOURNAL OF CHEMICAL PHYSICS 134, 134701 (2011) Binding of hydrogen on benzene, coronene the binding energy curves of hydrogen on benzene, coronene, and graphene. The DMC results on benzene agree

  2. Benzene/nitrous oxide flammability in the precipitate hydrolysis process

    SciTech Connect (OSTI)

    Jacobs, R A [Du Pont de Nemours (E.I.) and Co., Aiken, SC (USA). Savannah River Lab.

    1989-09-18T23:59:59.000Z

    The HAN (hydroxylamine nitrate) process for destruction of nitrite in precipitate hydrolysis produces nitrous oxide (N2O) gas as one of the products. N2O can form flammable mixtures with benzene which is also present due to radiolysis and hydrolysis of tetraphenylborate. Extensive flame modeling and explosion testing was undertaken to define the minimum oxidant for combustion of N2O/benzene using both nitrogen and carbon dioxide as diluents. The attached memorandum interprets and documents the results of the studies.

  3. Benzene formation in the inner regions of protostellar disks

    E-Print Network [OSTI]

    Paul M. Woods; Karen Willacy

    2006-12-08T23:59:59.000Z

    Benzene (c-C6H6) formation in the inner 3 AU of a protostellar disk can be efficient, resulting in high abundances of benzene in the midplane region. The formation mechanism is different to that found in interstellar clouds and in protoplanetary nebulae, and proceeds mainly through the reaction between allene (C3H4) and its ion. This has implications for PAH formation, in that some fraction of PAHs seen in the solar system could be native rather than inherited from the interstellar medium.

  4. Synthesis of macroporous poly(styrene-divinyl benzene) microspheres by surfactant reverse micelles swelling method

    E-Print Network [OSTI]

    Gu, Tingyue

    Synthesis of macroporous poly(styrene-divinyl benzene) microspheres by surfactant reverse micelles poly(styrene-divinyl benzene) microspheres with pore size of about 500 nm were prepared by a new method

  5. Supramolecular assemblies of 1,4-benzene diboronic acid on KCl(001)

    E-Print Network [OSTI]

    Boyer, Edmond

    Supramolecular assemblies of 1,4-benzene diboronic acid on KCl(001) Rémy Pawlak, Laurent Nony The self-assembly of benzene diboronic acid molecules on KCl(001) is investigated at room temperature

  6. Sources and distribution of CuO-derived benzene carboxylic acids in soils and sediments

    E-Print Network [OSTI]

    Long, Bernard

    Sources and distribution of CuO-derived benzene carboxylic acids in soils and sediments Angela F vas- cular plant-derived OC, through the environment. The method produces a suite of benzene

  7. Insights into the different dioxygen activation pathways of methane and toluene monooxygenase hydroxylases

    E-Print Network [OSTI]

    Bochevarov, Arteum D.

    The methane and toluene monooxygenase hydroxylases (MMOH and TMOH, respectively) have almost identical active sites, yet the physical and chemical properties of their oxygenated intermediates, designated P*, H[subscript ...

  8. New packing in absorption systems for trapping benzene from coke-oven gas

    SciTech Connect (OSTI)

    V.V. Grabko; V.M. Li; T.A. Shevchenko; M.A. Solov'ev [Giprokoks, the State Institute for the Design of Coke-Industry Enterprises, Kharkov (Ukraine)

    2009-07-15T23:59:59.000Z

    The efficiency of benzene removal from coke-oven gas in absorption units OAO Alchevskkoks with new packing is assessed.

  9. Effect of ozonation on the composition of crude coal-tar benzene

    SciTech Connect (OSTI)

    Semenova, S.A.; Patrakov, Y.F. [Russian Academy of Sciences, Kemerovo (Russian Federation)

    2007-05-15T23:59:59.000Z

    The effect of ozonation on the composition of crude benzene produced by the coal-tar chemical industry was studied.

  10. Using urinary biomarkers to elucidate dose-related patterns of human benzene metabolism

    E-Print Network [OSTI]

    California at Berkeley, University of

    Using urinary biomarkers to elucidate dose-related patterns of human benzene metabolism Sungkyoon; Fax: þ1 919 966 0521; Email: stephen_rappaport@unc.edu Although the toxicity of benzene has been, particularly at low levels of exposure. We investigated unmetabolized benzene in urine (UBz) and all major

  11. Modeling benzene plume elongation mechanisms exerted by ethanol using RT3D with a general

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    Modeling benzene plume elongation mechanisms exerted by ethanol using RT3D with a general substrate ethanol on benzene fate and transport in fuel-contaminated groundwater and to discern the most influential benzene plume elongation mechanisms. The model, developed as a module for the Reactive Transport in 3

  12. Measurements of benzene concentration by difference-frequency laser absorption spectroscopy

    E-Print Network [OSTI]

    Measurements of benzene concentration by difference-frequency laser absorption spectroscopy Weidong Chen, Fabrice Cazier, Frank Tittel, and Daniel Boucher Measurements of benzene concentration based:sapphire lasers in a GaSe nonlinear optical crystal. A minimum benzene concentration detection of 11.5 parts

  13. The Mechanism of Benzene-induced Leukemia: A Hypothesis and Speculations on

    E-Print Network [OSTI]

    California at Berkeley, University of

    The Mechanism of Benzene-induced Leukemia: A Hypothesis and Speculations on the Causes of Leukemia hypothesis for benzene-induced leukemia is proposed. Key components of the hypothesis include a) activation of benzene in the liver to phenolic metabolites; b) transport of these metabo- lites to the bone marrow

  14. Carcinogenesis vol.19 no.9 pp.15651571, 1998 Hemoglobin and albumin adducts of benzene oxide among

    E-Print Network [OSTI]

    California at Berkeley, University of

    Carcinogenesis vol.19 no.9 pp.1565­1571, 1998 Hemoglobin and albumin adducts of benzene oxide among workers exposed to high levels of benzene Karen Yeowell-O'Connell, Nathaniel Rothman1, Martyn T.Smith2_rappaport@unc.edu Benzene oxide (BO) reacts with cysteinyl residues in hemo- globin (Hb) and albumin (Alb) to form protein

  15. Grain boundary premelting in crystalline benzene as studied by proton N.M.R.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    2489 Grain boundary premelting in crystalline benzene as studied by proton N.M.R. C. J. Craven. 2014 The phenomenon of premelting has been investigated by proton n.m.r. in polycrystalline benzene in the case of polycrystalline benzene in which the molecular dynamics feature is essentially analogous

  16. Kekule's Benzene Structure: A Case Study of Teaching Usefulness of Symmetry

    E-Print Network [OSTI]

    Kreinovich, Vladik

    Kekul´e's Benzene Structure: A Case Study of Teaching Usefulness of Symmetry Olga Kosheleva1 at El Paso 500 W. University El Paso, TX 79968, USA olgak@utep.edu, vladik@utep.edu Abstract Benzene is one of the basic building blocks of organic molecules. One of the reasons for benzene's ubiquity

  17. Response to Comment on "Adsorption and Electronic States of Benzene on Ordered MgO

    E-Print Network [OSTI]

    Goodman, Wayne

    Response to Comment on "Adsorption and Electronic States of Benzene on Ordered MgO and Al2O3 Thin on the electronic states of benzene adsorbed on two metal oxides,1 particularly for pointing out a reference to recent work on the vibronic spectra of solid benzene,2 the dearth of which we lamented

  18. 946 volume 117 | number 6 | June 2009 Environmental Health Perspectives Benzene is an important industrial chem-

    E-Print Network [OSTI]

    California at Berkeley, University of

    946 volume 117 | number 6 | June 2009 · Environmental Health Perspectives Research Benzene smoke [International Agency for Research on Cancer (IARC) 1989]. In fact, benzene is truly ubiq- uitous million in some workplaces (IARC 1989; Wallace 1996). This is worrisome because benzene causes leukemia

  19. Discovery of benzene cation in a very long-lived excited electronic state Myung Soo Kima)

    E-Print Network [OSTI]

    Kim, Myung Soo

    Discovery of benzene cation in a very long-lived excited electronic state Myung Soo Kima) and Chan, University of Suwon, Suwon 440-600, Korea Received 19 May 2000; accepted 8 September 2000 Presence of benzene chemistry. © 2000 American Institute of Physics. S0021-9606 00 01745-1 I. INTRODUCTION The benzene molecular

  20. Thermal decomposition of norbornane (bicyclo[2.2.1]heptane) dissolved in benzene.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Thermal decomposition of norbornane (bicyclo[2.2.1]heptane) dissolved in benzene. Experimental (dissolved in benzene) has been studied in a jet stirred reactor at temperatures between 873 and 973 K decomposition of the norbornane ­ benzene binary mixture has been performed. Reactions involved in the mechanism

  1. Population Toxicokinetics of Benzene Frederic Yves Bois,1 Elise T. Jackson,1 Kaija Pekari,2 and

    E-Print Network [OSTI]

    California at Berkeley, University of

    Population Toxicokinetics of Benzene Frederic Yves Bois,1 Elise T. Jackson,1 Kaija Pekari,2 these problems. As an example, we modeled the distribution and metabolism of benzene in humans. We derive statistical distributions for the parameters of a physiological model of benzene, on the basis of existing

  2. Electronvibration coupling in time-dependent density-functional theory: Application to benzene

    E-Print Network [OSTI]

    Bertsch George F.

    Electron­vibration coupling in time-dependent density-functional theory: Application to benzene G://jcp.aip.org/about/rights_and_permissions #12;Electron­vibration coupling in time-dependent density-functional theory: Application to benzene G for electron­vibration coupling, we apply it to the optical properties of the ­ * transitions in benzene

  3. Electronvibration coupling in time-dependent density-functional theory: Application to benzene

    E-Print Network [OSTI]

    Bertsch George F.

    Electron­vibration coupling in time-dependent density-functional theory: Application to benzene G for electron­vibration coupling, we apply it to the optical properties of the ­ * transitions in benzene with the electronic excitations. In this work, we have chosen the benzene model for an exploratory study

  4. Chemisorption of benzene and STM dehydrogenation products on Cu,,100... N. Lorente*

    E-Print Network [OSTI]

    Persson, Mats

    Chemisorption of benzene and STM dehydrogenation products on Cu,,100... N. Lorente* Laboratoire of individual chemisorbed benzene molecules on Cu 100 has recently been performed in atomic manipulation experiments J. Phys. Chem. A. 104, 2463 2000 ; Surf. Sci 451, 219 2000 . Benzene dissociates under controlled

  5. Electron Transfer Catalyzed [2 + 2] Cycloreversion of Benzene G. Devi Reddy and Olaf Wiest*

    E-Print Network [OSTI]

    Hudlicky, Tomas

    Electron Transfer Catalyzed [2 + 2] Cycloreversion of Benzene Dimers G. Devi Reddy and Olaf Wiest, Florida 32611-7200 Received December 8, 1998 The catalysis of the [2 + 2] cycloreversion of the anti-o,o-benzene dimer 1 and the syn-o,o- naphthalene-benzene dimer 2 through thermal and photoinduced electron transfer

  6. Anaerobic Benzene Oxidation in the Fe(III) Reduction Zone of

    E-Print Network [OSTI]

    Lovley, Derek

    Anaerobic Benzene Oxidation in the Fe(III) Reduction Zone of Petroleum-Contaminated Aquifers R O B North, University of Massachusetts, Amherst, Massachusetts 01003 The potential for anaerobic benzene. [14C]Benzene was not oxidized to 14CO2 at most sites examined, which is consistent with previous

  7. Benzene Increases Aneuploidy in the Lymphocytes of Exposed Workers: A Comparison of Data Obtained by

    E-Print Network [OSTI]

    California at Berkeley, University of

    Benzene Increases Aneuploidy in the Lymphocytes of Exposed Workers: A Comparison of Data Obtained Benzene is an established human leukemogen that increases the level of chromosome aberrations in lym and 8 in healthy benzene-exposed human subjects. Metaphase and interphase cells from the peripheral

  8. An Epidemiologic Study of Early Biologic Effects of Benzene in Chinese Workers

    E-Print Network [OSTI]

    California at Berkeley, University of

    An Epidemiologic Study of Early Biologic Effects of Benzene in Chinese Workers Nathaniel Rothman,1 and Anti-Epidemic Center, Shanghai, China Benzene is a recognized hematotoxin and leukemogen, but its a cross-sectional study of 44 healthy workers currently exposed to benzene (median 8-hr time

  9. Modulation of the Toxicity and Macromolecular Binding of Benzene Metabolites by NAD(P)H:Quinone

    E-Print Network [OSTI]

    California at Berkeley, University of

    Articles Modulation of the Toxicity and Macromolecular Binding of Benzene Metabolites by NAD, San Francisco, California 94143-0560 Received April 17, 1998 Benzene is oxidized in the liver of benzene metabolite toxicity. NQO1 expression reduced a class of hydroquinone- and benzenetriol-induced DNA

  10. Decreased levels of CXC-chemokines in serum of benzene-exposed workers identified by

    E-Print Network [OSTI]

    California at Berkeley, University of

    Decreased levels of CXC-chemokines in serum of benzene-exposed workers identified by array (received for review October 3, 2004) Benzene is an important industrial chemical and environmental contaminant that causes leukemia. To obtain mechanistic insight into benzene's mechanism of action, we

  11. Current Collapse in Tunneling Transport through Benzene M. H. Hettler,1

    E-Print Network [OSTI]

    Current Collapse in Tunneling Transport through Benzene M. H. Hettler,1 W. Wenzel,1 M. R. Wegewijs; published 20 February 2003) We investigate the electrical transport through a system of benzene coupled model for the electrons of the benzene is derived that includes general two-body interactions. After

  12. Mechanisms for the formation of benzene in the atmosphere of Titan E. H. Wilson1

    E-Print Network [OSTI]

    Atreya, Sushil

    Mechanisms for the formation of benzene in the atmosphere of Titan E. H. Wilson1 and S. K. Atreya (PAHs) are important interstellar species, and their precursor benzene (C6H6) has been detected in our solar system. In this study the possibility of benzene formation in the atmosphere of Titan

  13. Benzene is an important industrial chemical (> 2 billion gallons produced annually in the

    E-Print Network [OSTI]

    California at Berkeley, University of

    Benzene is an important industrial chemical (> 2 billion gallons produced annually in the United leukemia (Snyder 2002). However, the mechanisms of benzene-induced hematotoxicity and leukemo- genesis further light on these mechanisms and better understand the risk benzene poses, we examined the effects

  14. Negative Differential Conductance in a Benzene-Molecular Device Maarten R. Wegewijs1

    E-Print Network [OSTI]

    Negative Differential Conductance in a Benzene-Molecular Device Maarten R. Wegewijs1 , Matthias (Received August 14, 2002) KEYWORDS: molecular, tunneling, transport, benzene, blocking 1. Introduction of the molecular orbitals leads to nontrivial current voltage (I-V ) characteristics.6,7) Using benzene

  15. Evidence of a tilted columnar structure for mesomorphic phases of benzene-hexa-n-alkanoates

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1285 Evidence of a tilted columnar structure for mesomorphic phases of benzene-hexa-n-alkanoates F. 2014 Optical observations on the mesomorphs of benzene-hexa-n-alkanoates, and their admixtures with benzene, show that the planes of these discotic molecules are not perpendicular to the columns in which

  16. OH-initiated oxidation of benzene Part I. Phenol formation under atmospheric conditions

    E-Print Network [OSTI]

    OH-initiated oxidation of benzene Part I. Phenol formation under atmospheric conditions Rainer-radical initiated oxidation of benzene was studied in two simulation chambers: (1) the large-volume outdoor chamber-red spectroscopy (FTIR) were used to simultaneously measure phenol and benzene. The second study used only FTIR

  17. LETTER TO THE EDITOR Regarding ``Meta-analysis and Causal Inference: A Case Study of Benzene

    E-Print Network [OSTI]

    California at Berkeley, University of

    LETTER TO THE EDITOR Regarding ``Meta-analysis and Causal Inference: A Case Study of Benzene of a causal association between non-Hodgkin lymphoma (NHL) and benzene and between NHL and petroleum refinery identified provide ``further evidence that benzene exposure causes NHL.'' However, his review of each

  18. Molecular dynamics simulations of the effects of salts on the aggregation properties of benzene in water.

    SciTech Connect (OSTI)

    Smith, P. E.

    2003-07-16T23:59:59.000Z

    The specific aims of the project were: to provide an atomic level description of the interactions between benzene, water and ions in solutions. To determine the degree of association between two benzene molecules in aqueous and salt solutions. To investigate the structure and dynamics of the interface between benzene and water or salt solution.

  19. Group Theoretical Analysis of the Vibrational and Electronic Spectrum of Benzene Frank Rioux

    E-Print Network [OSTI]

    Rioux, Frank

    Group Theoretical Analysis of the Vibrational and Electronic Spectrum of Benzene Frank Rioux CSB|SJU This tutorial deals with the interpretation of the vibrational and electronic spectra of benzene using group benzene's electrons. The symmetry of the relevant -electron molecular orbitals is determined by examining

  20. Viscosity and reptation time in polystyrene-benzene semidilute solutions M. Adam and M. Delsanti

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    L-523 Viscosity and reptation time in polystyrene-benzene semidilute solutions M. Adam and M viscosity ~ and reptation time TR in semidilute polystyrene-benzene solutions. We have obtained, our aim is to study the viscoelastic properties of polystyrene-benzene systems in a well defined

  1. The benzene molecule as a molecular resonant-tunneling transistor M. Di Ventraa)

    E-Print Network [OSTI]

    Pantelides, Sokrates T.

    The benzene molecule as a molecular resonant-tunneling transistor M. Di Ventraa) and S. T of transport through a benzene-1, 4-dithiolate molecule with a third capacitive terminal gate . We find rectification was demonstrated in 1993.2 More recently, Reed et al. investigated the benzene-1, 4-dithiol rings

  2. Distorted benzene bearing two bulky substituents on adjacent positions: structure of

    E-Print Network [OSTI]

    Kaszynski, Piotr

    Distorted benzene bearing two bulky substituents on adjacent positions: structure of 1,2-bis(1,2-dicarba-closo-dodecaboran-1-yl)benzene Yasuyuki Endo,a,* Chalermkiat Songkram,b Kiminori Ohta,a Piotr analysis of 1,2-bis(o-carboranyl)benzene were performed to examine the steric effects of the two extremely

  3. EFFECTS OF BENZENE (A TOXIC COMPONENT OF PETROLEUM) ON SPAWNING PACIFIC HERRING, CLUPEA HARENGUS PALLASI

    E-Print Network [OSTI]

    EFFECTS OF BENZENE (A TOXIC COMPONENT OF PETROLEUM) ON SPAWNING PACIFIC HERRING, CLUPEA HARENGUS and larvae through yolk absorption, 43%. Exposure to benzene also induced premature spawning and resulted-labeled benzene and/or metabolites in ovarian eggs (14 times initial concentration in water in 24-48 h; 1.4 ILlig

  4. Resonant ion-dip infrared spectroscopy of benzene,,water...9: Expanding the cube

    E-Print Network [OSTI]

    Zwier, Timothy S.

    Resonant ion-dip infrared spectroscopy of benzene­,,water...9: Expanding the cube Christopher J the hydrogen-bonding topologies of three isomers of benzene­ water 9. Isomers I and II, with R2PI transitions shifted, respectively, by 77 and 63 cm 1 from the benzene monomer, have similar intensities in the R2PI

  5. Noncovalent interaction or chemical bonding between alkaline earth cations and benzene? A quantum chemistry study using

    E-Print Network [OSTI]

    Sussman, Joel L.

    Noncovalent interaction or chemical bonding between alkaline earth cations and benzene? A quantum earth metal ion±benzene complexes were performed using the density-functional theory (DFT) B3LYP and ab of the al- kaline earth metal ions to benzene may be attributed to s±p and p±p interactions, which are signi

  6. Two-dimensional 1,3,5-Tris(4-carboxyphenyl)benzene self-assembly at

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Two-dimensional 1,3,5-Tris(4-carboxyphenyl)benzene self-assembly at the 1-phenyloctane-assembly of star-shaped 1,3,5-Tris(4-carboxyphenyl)benzene molecules is investigated. Scanning tunneling microscopy.22 showed that 1,3,5-Tris(4-carboxyphenyl)benzene star-shaped molecules can form two distinc self

  7. UPTAKE, DISTRIBUTION, AND DEPURATION OF 14C-BENZENE IN NORTHERN ANCHOVY, ENGRAULIS MORDAX, AND

    E-Print Network [OSTI]

    UPTAKE, DISTRIBUTION, AND DEPURATION OF 14C-BENZENE IN NORTHERN ANCHOVY, ENGRAULIS MORDAX striped bass, Morone saxatilis, were exposed to sublethal concentra- tions of HC-benzene for 48 h exhibited a rapid uptake over a wide range of benzene concentrations in the water column. Accumulation

  8. Modeling and Optimal Regulation of Erythropoiesis Subject to Benzene Intoxication

    E-Print Network [OSTI]

    humans and laboratory animals [11, 16]. Increased incidence of acute myelogenous leukemia in humans obtained in vitro [5, 6]. Since in vitro metabolic parameters are also available for humans, the model could then be extrapolated to humans for risk assessment. Since benzene is a known human leukemogen

  9. Lithium-Mediated Benzene Adsorption on Graphene and Graphene Nanoribbons

    E-Print Network [OSTI]

    Hod, Oded

    Lithium-Mediated Benzene Adsorption on Graphene and Graphene Nanoribbons Dana Krepel and Oded Hod on lithium adsorption sites at the surface of graphene and nanoribbons thereof are investigated. The effects, bare lithium adsorption turns armchair graphene nanoribbons metallic and their zigzag counterparts half

  10. Process for hydrocracking carbonaceous material to provide fuels or chemical feed stock

    DOE Patents [OSTI]

    Duncan, Dennis A. (Downers Grove, IL)

    1980-01-01T23:59:59.000Z

    A process is disclosed for hydrocracking coal or other carbonaceous material to produce various aromatic hydrocarbons including benzene, toluene, xylene, ethylbenzene, phenol and cresols in variable relative concentrations while maintaining a near constant maximum temperature. Variations in relative aromatic concentrations are achieved by changing the kinetic severity of the hydrocracking reaction by altering the temperature profile up to and quenching from the final hydrocracking temperature. The relative concentration of benzene to the alkyl and hydroxyl aromatics is increased by imposing increased kinetic severity above that corresponding to constant heating rate followed by immediate quenching at about the same rate to below the temperature at which dehydroxylation and dealkylation reactions appreciably occur. Similarly phenols, cresols and xylenes are produced in enhanced concentrations by adjusting the temperature profile to provide a reduced kinetic severity relative to that employed when high benzene concentrations are desired. These variations in concentrations can be used to produce desired materials for chemical feed stocks or for fuels.

  11. Electronic structure of the benzene dimer cation Piotr A. Pieniazek, Anna I. Krylov, and Stephen E. Bradforth

    E-Print Network [OSTI]

    Krylov, Anna I.

    Electronic structure of the benzene dimer cation Piotr A. Pieniazek, Anna I. Krylov, and Stephen E-0482 Received 20 March 2007; accepted 22 May 2007; published online 31 July 2007 The benzene and benzene dimer benzene. Both sandwich and t-shaped structures feature intense charge resonance bands, whose location

  12. Synthesis, Structure, and Reactivity of O-Donor Ir(III) Complexes: C-H Activation Studies with Benzene

    E-Print Network [OSTI]

    Goddard III, William A.

    with Benzene Gaurav Bhalla, Xiang Yang Liu, Jonas Oxgaard, William A. Goddard, III, and Roy A. Periana. All the R-Ir-Py complexes undergo quantitative, intermolecular CH activation reactions with benzene to benzene to generate a discrete benzene complex, cis-R-Ir-PhH; and (D) rapid C-H cleavage. Kinetic isotope

  13. PHYSICAL REVIEW B 86, 245405 (2012) Benzene adsorbed on metals: Concerted effect of covalency and van der Waals bonding

    E-Print Network [OSTI]

    Alavi, Ali

    2012-01-01T23:59:59.000Z

    PHYSICAL REVIEW B 86, 245405 (2012) Benzene adsorbed on metals: Concerted effect of covalency, but the role of the vdW energy in chemisorbed systems remains unclear. Here we study the interaction of benzene of covalently bonded benzene than they do when benzene is physisorbed. Comparison to experimental data

  14. Molecular Dynamics Study of a Surfactant-Mediated Decane-Water Interface: Effect of Molecular Architecture of Alkyl Benzene Sulfonate

    E-Print Network [OSTI]

    Goddard III, William A.

    Architecture of Alkyl Benzene Sulfonate Seung Soon Jang, Shiang-Tai Lin, Prabal K. Maiti, Mario Blanco the attachment position of benzene sulfonate on the hexadecane backbone, at the decane-water interface benzene sulfonates, denoted by m-C16, indicating a benzene sulfonate group attached to the mth carbon

  15. Computer simulations of benzene in faujasite-type zeolites

    SciTech Connect (OSTI)

    Henson, N.J.; Cheetham, A.K. [California Univ., Santa Barbara, CA (United States). Dept. of Materials; Redondo, A. [Los Alamos National Lab., NM (United States); Levine, S.M.; Newsam, J.M. [Biosym Technologies Inc., San Diego, CA (United States)

    1994-03-01T23:59:59.000Z

    The exact nature of the cation-benzene ring interaction is not yet known. In order to remedy this, energy minimization and Monte Carlo methods were used to probe the location and energetics of benzene in sodium zeolite-X and -Y. Sorption energies for the six-ring binding site in each of the zeolite models with the two forcefields (cff91 and cvff) are tabulated as function of Si/Al ratio. Both forcefields predict similar binding sites for each system; however, the final energies are sensitive to form and parameterization of the forcefield. Further work is needed to refine the forcefield for zeolite-sorbate interactions. 5 figs, 21 refs, 2 tabs.

  16. Binding Energies in Benzene Dimers: Nonlocal Density Functional Calculations

    E-Print Network [OSTI]

    Aaron Puzder; Maxime Dion; David C. Langreth

    2005-09-15T23:59:59.000Z

    The interaction energy and minimum energy structure for different geometries of the benzene dimer has been calculated using the recently developed nonlocal correlation energy functional for calculating dispersion interactions. The comparison of this straightforward and relatively quick density functional based method with recent calculations can elucidate how the former, quicker method might be exploited in larger more complicated biological, organic, aromatic, and even infinite systems such as molecules physisorbed on surfaces, and van der Waals crystals.

  17. Tip-contact related low-bias negative differential resistance and rectifying effects in benzene–porphyrin–benzene molecular junctions

    SciTech Connect (OSTI)

    Cheng, Jue-Fei [College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China); School of Electronics and Information Engineering, Suzhou Vocational University, Suzhou 215104 (China); Zhou, Liping, E-mail: zhoulp@suda.edu.cn, E-mail: leigao@suda.edu.cn; Liu, Man; Yan, Qiang; Han, Qin; Gao, Lei, E-mail: zhoulp@suda.edu.cn, E-mail: leigao@suda.edu.cn [College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China)

    2014-11-07T23:59:59.000Z

    The electronic transport properties of benzene–porphyrin–benzene (BPB) molecules coupled to gold (Au) electrodes were investigated. By successively removing the front-end Au atoms, several BPB junctions with different molecule-electrode contact symmetries were constructed. The calculated current–voltage (I–V) curves depended strongly on the contact configurations between the BPB molecules and the Au electrodes. In particular, a significant low-voltage negative differential resistance effect appeared at ?0.3 V in the junctions with pyramidal electrodes on both sides. Along with the breaking of this tip-contact symmetry, the low-bias negative differential resistance effect gradually disappeared. This tip-contact may be ideal for use in the design of future molecular devices because of its similarity with experimental processes.

  18. Assessing the Exposure and Health Risks of Secondhand Smoke in Restaurants and Bars by Workers and Patrons & Evaluating the Efficacy of Different Smoking Policies in Beijing Restaurants and Bars

    E-Print Network [OSTI]

    Liu, Ruiling

    2012-01-01T23:59:59.000Z

    acetaldehyde, formaldehyde and acrolein), hydrocarbons (suchaldehydes, nitrous acid, acrolein, benzene, toluene,3-Ethenylpridine Acetonitrile Acrolein Acrylonitrile Benzene

  19. Chemical Engineering Journal 87 (2002) 101110 Co-treatment of H2S and toluene in a biotrickling filter

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    Chemical Engineering Journal 87 (2002) 101­110 Co-treatment of H2S and toluene in a biotrickling-gases contain H2S and a wide range of volatile organic compounds (VOCs). Since co-treatment of odors and VOCs in biotrickling filters is a relatively unexplored area, the simultaneous biotreatment of H2S and toluene (as

  20. Quantum/Classical Mechanical Comparison of Cation-Interactions between Tetramethylammonium and Benzene

    E-Print Network [OSTI]

    Sussman, Joel L.

    and Benzene Clifford Felder, Hua-Liang Jiang,,§,|, Wei-Liang Zhu,§,| Kai-Xian Chen,§ Israel Silman, Simone A-methyl groups with a benzene ring, by use of density-functional theory (DFT) methods B3LYP/6-31G* and B3LYP/6 profiles of the complex as benzene was moved away from TMA in 0.2 Å intervals. Hence it is possible to use

  1. Occupational Exposure to Benzene from Painting with Epoxy and Other High Performance Coatings

    SciTech Connect (OSTI)

    JAHN, STEVEN

    2005-04-20T23:59:59.000Z

    Following the discovery of trace benzene in paint products, an assessment was needed to determine potential for benzene exposures to exceed the established ACGIH Threshold Limit Value (TLV) during painting operations. Sample data was collected by area industrial hygienists for benzene during routine maintenance and construction activities at Savannah River Site. A set of available data from the IH database, Sentry, was analyzed to provide guidance to the industrial hygiene staff and draw conclusions on the exposure potential during typical painting operations.

  2. Palladium-Catalyzed Direct Functionalization of Aromatic C-H Bonds: Development of Methods for Direct Amination and Mechanistic Studies of Direct Arylation of Benzene and Pyridine N-Oxide

    E-Print Network [OSTI]

    Tan, Yichen

    2013-01-01T23:59:59.000Z

    barrier of the reactions of benzene with phosphine-ligatedStudy on Direct Arylation of Benzene ………………..95-142proposed, and reaction of benzene and phthalimide in the

  3. Kinetic effects of toluene blending on the extinction limit of n-decane diffusion flames

    E-Print Network [OSTI]

    Ju, Yiguang

    analyses of kinetic path ways and species transport on flame extinction were also conducted. The results and emission properties, such as the ignition delay times, extinction limits, flame speeds, species profilesKinetic effects of toluene blending on the extinction limit of n-decane diffusion flames Sang Hee

  4. Removal of Toluene in Air by Non Thermal Plasma-Catalysis Hybrid , H. T. Pham

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Removal of Toluene in Air by Non Thermal Plasma-Catalysis Hybrid System A. Khacef , H. T. Pham , A Orléans Cedex 02, France * Institute of Applied Material Science, VAST, 1 Mac Dinh Chi, HCMC, Vietnam with heterogeneous catalysts. This combination can be either single-stage (in-plasma catalysis, IPC) or two

  5. Applied Catalysis B: Environmental 29 (2001) 327336 Gas-phase photo-oxidation of toluene using

    E-Print Network [OSTI]

    2001-01-01T23:59:59.000Z

    Applied Catalysis B: Environmental 29 (2001) 327­336 Gas-phase photo-oxidation of toluene using reserved. PII: S0926-3373(00)00211-3 #12;328 A.J. Maira et al. / Applied Catalysis B: Environmental 29.V. All rights reserved. Keywords: Photo-catalysis; Titanium dioxide; Nanoparticles; Volatile organic

  6. Effect of Ethanol, Acetate, and Phenol on Toluene Degradation Activity and todlux

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    Effect of Ethanol, Acetate, and Phenol on Toluene Degradation Activity and tod­lux Expression with increasing influent concentrations of ethanol, acetate, or phenol. Three inhibitory mechanisms were) by acetate and ethanol, which was quantified by a decrease in specific bioluminescence; (2) competitive

  7. Benzene Generation Testing for Tank 48H Waste Disposition

    SciTech Connect (OSTI)

    Peters, T

    2005-05-13T23:59:59.000Z

    In support for the Aggregation option1, researchers performed a series of tests using actual Tank 48H slurries. The tests were designed to examine potential benzene generation issues if the Tank 48H slurry is disposed to Saltstone. Personnel used the archived Tank 48H sample (HTF-E-03-127, collected September 17, 2003) for the experiments. The tests included a series of three experiments (Tests A, B, and F) performed in duplicate, giving a total of six experiments. Test A used Tank 48H slurry mixed with {approx}20:1 with Defense Waste Processing Facility (DWPF) Recycle from Tanks 21H and 22H. Test B used Tank 48H slurry mixed with {approx}2.7:1 with DWPF Recycle from Tanks 21H and 22H, while Test F used Tank 48H slurry as-is. Tests A and B occurred at 45 C, while Test F occurred at 55 C. Over a period of 8 weeks, personnel collected samples for analysis, once per week. Each sample was tested with the in-cell gamma counter. The researchers noted a decline in the cesium activity in solution which is attributed to temperature dependence of the complex slurry equilibrium. Selected samples were sent to ADS for potassium, boron, and cesium analysis. The benzene generation rate was inferred from the TPB destruction which is indirectly measured by the in-growth of cesium, potassium or boron. The results of all the analyses reveal no discernible in-growth of radiocesium, potassium or boron, indicating no significant tetraphenylborate (TPB) decomposition in any of the experiments. From boron measurements, the inferred rate of TPB destruction remained less than 0.332 mg/(L-h) implying a maximum benzene generation rate of <0.325 mg/(L-h).

  8. Atomic Structure of Benzene Which Accounts for Resonance Energy

    E-Print Network [OSTI]

    Raji Heyrovska

    2008-07-09T23:59:59.000Z

    Benzene is a hexagonal molecule of six carbon atoms, each of which is bound to six hydrogen atoms. The equality of all six CC bond lengths, despite the alternating double and single bonds, and the surplus (resonance) energy, led to the suggestion of two resonanting structures. Here, the new atomic structure shows that the bond length equality is due to three carbon atoms with double bond radii bound to three other carbon atoms with resonance bond radii (as in graphene). Consequently, there are two kinds of CH bonds of slightly different lengths. The bond energies account for the resonance energy.

  9. The development of a passive dosimeter for airborne benzene vapors

    E-Print Network [OSTI]

    Hager, David William

    1978-01-01T23:59:59.000Z

    THE DEVELOPMENT OF A PASSIVE DOSIMETER FOR AIRBORNE BENZENE VAPORS A Thesis DAVID NII LIAM HAGER Submitted to the Graduate Colleqe of Texas ASM University in partial fulfillment of the requirement for the d"gree of MASTER OF SC. IENCE May IB...7B Major Subject: Indus t& ial Hyqiene THE DEVELOPMENT OF A PASSIVE DOSIMETER FOR AIRBORNE BFNZENE VAPORS A Thesis by DAVID NILLIAM HAGER Approved as to style and content by: Z Chairman of Commi t e~ ~'g C'S~ Head of Department~ Member...

  10. Ab initio investigation of intermolecular interactions in solid benzene

    E-Print Network [OSTI]

    O. Bludsky; M. Rubes; P. Soldan

    2008-01-04T23:59:59.000Z

    A computational strategy for the evaluation of the crystal lattice constants and cohesive energy of the weakly bound molecular solids is proposed. The strategy is based on the high level ab initio coupled-cluster determination of the pairwise additive contribution to the interaction energy. The zero-point-energy correction and non-additive contributions to the interaction energy are treated using density functional methods. The experimental crystal lattice constants of the solid benzene are reproduced, and the value of 480 meV/molecule is calculated for its cohesive energy.

  11. Internal degrees of freedom and transport of benzene on graphite

    E-Print Network [OSTI]

    Astrid S. de Wijn

    2011-07-13T23:59:59.000Z

    In this paper, the chaotic internal degrees of freedom of a benzene molecule adsorbed on a graphite substrate, their interplay with thermal noise, and their effects on the diffusion and drift are investigated analytically by making use of the presence of two different time scales as well as by molecular-dynamics simulations. The effects of thermal noise are investigated, and it is found that noise does not significantly alter the dynamics of the internal degrees of freedom, yet affects the friction and diffusion of the center of mass. Qualitative and quantitative theoretical predictions for the friction and diffusion of the molecule on the substrate are made and are compared to molecular-dynamics simulations. Contributions to the friction and diffusion from the finite heat bath as well as the slow dynamics of the center of mass are formally identified. It is shown that the torsion in benzene, which dominates the nonlinear coupling, significantly affects the friction of the molecule on the surface. The results compare favorably with recent results from He/neutron spin echo experiments on this system. Based on the analytical and numerical results, some suggestions are made for experimental conditions under which the effects of internal degrees of freedom might be observable.

  12. Intrinsic bioremediation of a BTEX and MTBE plume under mixed aerobic/denitrifying conditions

    SciTech Connect (OSTI)

    Borden, R.C.; Daniel, R.A. [North Carolina State Univ., Raleigh, NC (United States). Civil Engineering Dept.

    1995-09-01T23:59:59.000Z

    A shallow Coastal Plain aquifer in rural Sampson Country, North Carolina, has been contaminated with petroleum hydrocarbon from a leaking underground storage tank containing gasoline.An extensive field characterization has been performed to define the horizontal and vertical distribution of soluble gasoline components and indicator parameters. A plume of dissolved methyl tert-butyl ether (MTBE) and the aromatic hydrocarbons benzene, toluene, ethylbenzene, and xylene isomers (BTEX) is present in the aquifer and has migrated over 600 ft from the source area. Background dissolved oxygen concentrations range from 7 to 8 mg/L, and nitrate concentrations range from 5 to 22 mg/L as N due to extensive fertilization of fields surrounding the spill. In the center of the BTEX plume, oxygen concentrations decline to less than 1 mg/L while nitrate concentrations remain high. The total mass flux of MTBE and all BTEX components decline with distance downgradient relative to a conservative tracer (chloride). At the source, the total BTEX concentration exceeds 75 mg/L while 130 ft downgradient, total BTEX concentrations are less than 4.9 mg/L, a 15-fold reduction. Toluene and ethylbenzene decline most rapidly followed by m-p-xylene, o-xylene and finally benzene. Biodegradation of TEX appears to be enhanced by the excess nitrate present in the aquifer while benzene biodegradation appears to be due to strictly aerobic processes.

  13. Femtosecond Near-Infrared Laser Desorption of Multilayer Benzene on Pt{111}: A Molecular Newton's Cradle?

    E-Print Network [OSTI]

    Levis, Robert J.

    Femtosecond Near-Infrared Laser Desorption of Multilayer Benzene on Pt{111}: A Molecular Newton Recently, the intense near-infrared laser desorption of intact benzene molecules has been reported.1 Three to alter the pure thermal distribution to one having a stream velocity.4 The high heating rates achievable

  14. Hydrologic and geochemical controls on soluble benzene migration in sedimentary basins

    E-Print Network [OSTI]

    Polly, David

    , a coupled ground- water flow and heat transfer model computes the hydraulic head, stream function, and temperature in the basin. A coupled mass transport model simulates water washing of benzene from an oil reservoir and its miscible, advective/dispersive transport by groundwater. Benzene mass transfer at the oil­water

  15. Adsorption of Benzene, Fluorobenzene and Meta-di-Fluorobenzene on Cu(110): A Computational Study

    E-Print Network [OSTI]

    Gao, Hongjun

    Adsorption of Benzene, Fluorobenzene and Meta-di-Fluorobenzene on Cu(110): A Computational Study L.interscience.wiley.com). Abstract: We modelled the adsorption of benzene, fluorobenzene and meta-di-fluorobenzene on Cu(110) by Den- sity Functional Theory. We found that the adsorption configuration depends on the coverage. At high

  16. Impact of Ethanol on Benzene Plume Lengths: Microbial and Modeling Studies

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    Impact of Ethanol on Benzene Plume Lengths: Microbial and Modeling Studies Rula A. Deeb1 ; Jonathan with Federal Clean Air Act requirements for carbon monoxide and ozone attainment, ethanol is being considered as a replacement for MTBE. The objective of this study is to evaluate the potential impact of ethanol on benzene

  17. A Multicompartment LiverBased Pharmacokinetic Model for Benzene and Its Metabolites in Mice

    E-Print Network [OSTI]

    extrapolated to predict in vivo data for benzene metabolism and dosimetry. 1 Introduction and Problem in a variety of blood and bone marrow disorders in both humans and laboratory animals [9, 18]. IncreasedA Multicompartment Liver­Based Pharmacokinetic Model for Benzene and Its Metabolites in Mice Cammey

  18. A Multicompartment Liver-Based Pharmacokinetic Model for Benzene and Its Metabolites in Mice

    E-Print Network [OSTI]

    extrapolated to predict in vivo data for benzene metabolism and dosimetry. 1 Introduction and Problem in a variety of blood and bone marrow disorders in both humans and laboratory animals [9, 18]. IncreasedA Multicompartment Liver-Based Pharmacokinetic Model for Benzene and Its Metabolites in Mice Cammey

  19. Physiologically Based Pharmacokinetic Modeling of Benzene Metabolism in Mice through Extrapolation

    E-Print Network [OSTI]

    metabolic constants for humans can subsequently be extrapolated to predict the dosimetry of benzene and itsPhysiologically Based Pharmacokinetic Modeling of Benzene Metabolism in Mice through Extrapolation parameters are also available for humans. Unknown parameters were estimated by fitting the model to published

  20. Analytical solution of electronic transport through a benzene molecule using lattice Green's functions

    E-Print Network [OSTI]

    E. J. C. Dias; N. M. R. Peres

    2015-02-25T23:59:59.000Z

    Using a Green's function formalism we derive analytical expressions for the electronic transmittance through a benzene ring. To motivate the approach we first solve the resonant level system and then extend the method to the benzene case. These results can be used to validate numerical methods.

  1. Intermolecular C?H bond activation of benzene and pyridines by a vanadium(III) alkylidene including a stepwise conversion of benzene to a vanadium-benzyne complex

    SciTech Connect (OSTI)

    Andino, José G.; Kilgore, Uriah J.; Pink, Maren; Ozarowski, Andrew; Krzystek, J.; Telser, Joshua; Baik, Mu-Hyun; Mindiola, Daniel J. (Roosevelt); (FSU); (Indiana)

    2012-01-20T23:59:59.000Z

    Breaking of the carbon-hydrogen bond of benzene and pyridine is observed with (PNP)V(CH{sub 2}tBu){sub 2} (1), and in the case of benzene, the formation of an intermediate benzyne complex (C) is proposed, and indirect proof of its intermediacy is provided by identification of (PNP)VO({eta}{sup 2}-C{sub 6}H{sub 4}) in combination with DFT calculations.

  2. Tuning the oxide/organic interface: Benzene on SnO2,,101... Matthias Batzill,a)

    E-Print Network [OSTI]

    Diebold, Ulrike

    Tuning the oxide/organic interface: Benzene on SnO2,,101... Matthias Batzill,a) Khabibulakh Katsiev,16 As a model molecule for simulating an organic semiconductor film benzene was chosen as a simple -conjugated

  3. Catalytic Transformation of C7-C9 Methyl Benzenes over USY-based FCC Zeolite Catalyst

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    in the petrochemical market. Most of the currently working isomerization plants are using zeolite based catalysts. One) and the diphenyl methane mechanism. It was shown that toluene disproportionation does not require Brönsted acid

  4. Aromatic hydrocarbons associated with brines from geopressured wells. Annual report, fiscal 1985

    SciTech Connect (OSTI)

    Keeley, D.F.; Meriwether, J.R.

    1985-01-01T23:59:59.000Z

    Samples of cryocondensates - materials condensed at - 78.5/sup 0/C were taken on a regular basis from the gas stream for the USDOE geopressured wells. Most of the data has been taken from the Gladys McCall well as it has flowed on a regular and almost continous basis. The cryocondensates, not the ''condensate'' from gas wells, are almost exclusively aromatic hydrocarbons, primarily benzene, toluene, ethylbenzene, and the xylenes, but contain over 95 compounds, characterized using gas chromatographic-mass spectroscopy. The solubility in water and brine of benezene, toluene, ethylbenzene and o-xylene, some of the components of the cryocondensate, as well as distribution coefficients between water or brine and a standard oil have been measured. 25 refs.

  5. Clustering Dynamics of the Metal-Benzene Sandwich Complex: The Role of Microscopic Structure of the Solute In the Bis(6-benzene)chromium Arn Clusters (n ) 1-15)

    E-Print Network [OSTI]

    Kim, Sang Kyu

    Clustering Dynamics of the Metal-Benzene Sandwich Complex: The Role of Microscopic Structure of the Solute In the Bis(6-benzene)chromium ·Arn Clusters (n ) 1-15) Kyo-Won Choi, Sunyoung Choi, Doo-Sik AhnVised Manuscript ReceiVed: June 25, 2008 Ar clustering dynamics around the metal-benzene sandwich complex, bis(6

  6. Benzene Exposure and Risk of Non-Hodgkin Lymphoma Martyn T. Smith, Rachael M. Jones, and Allan H. Smith

    E-Print Network [OSTI]

    California at Berkeley, University of

    Benzene Exposure and Risk of Non-Hodgkin Lymphoma Martyn T. Smith, Rachael M. Jones, and Allan H of California, Berkeley, California Abstract Exposure to benzene, an important industrial chemical and component studies that identified probable occupational exposures to benzene and NHL morbidity or mortality. We

  7. Electronic structure of benzene adsorbed on single-domain Si,,001...-,,2 1...: A combined experimental and theoretical study

    E-Print Network [OSTI]

    Birkenheuer, Uwe

    Electronic structure of benzene adsorbed on single-domain Si,,001...-,,2 1...: A combined Received 20 October 1997; accepted 31 December 1997 Benzene adsorption on a single-domain Si 001 -(2 1 for the saturated benzene layer exhibit well-defined polarization and azimuthal dependencies compatible with a flat

  8. (CANCER RESEARCH 50, 393-399. January 15. 1990] Characterization of Micronuclei Induced in Human Lymphocytes by Benzene

    E-Print Network [OSTI]

    California at Berkeley, University of

    Lymphocytes by Benzene Metabolites1 Janice W. Yager, David A. Eastmond,2 Moire L. Robertson, William M Division, Lawrence Livermore National Laboratory, Livermore, California 94550 fD. A. E.] ABSTRACT Benzene is an established human leukemogen. Workers occupational!) exposed to benzene exhibit increased frequencies of both

  9. J. Am. Chem. SOC. The m ( b 2 u ) Mode of Benzene in SOand SI and the

    E-Print Network [OSTI]

    Haas, Yehuda

    J. Am. Chem. SOC. The m ( b 2 u ) Mode of Benzene in SOand SI and the Distortive Nature of the z structure. The symmetry analysis of the vibrational modes of benzene by Wilson4was one of the first and assigned of vibrational spectra of benzene and its derivatives. Early on it was noticed that b2u modes

  10. Electronic Structure and Properties of Transition Metal-Benzene Ravindra Pandey, Bijan K. Rao,*, Purusottam Jena, and Miguel Alvarez Blanco

    E-Print Network [OSTI]

    Pandey, Ravi

    Electronic Structure and Properties of Transition Metal-Benzene Complexes Ravindra Pandey, Bijan Kd transition metal atoms (M) interacting with benzene molecules (Bz) is carried out using density. The variation of the metal-benzene distances, dissociation energies, ionization potentials, electron affinities

  11. Polymorphisms in genes involved in DNA double-strand break repair pathway and susceptibility to benzene-induced hematotoxicity

    E-Print Network [OSTI]

    California at Berkeley, University of

    to benzene-induced hematotoxicity Min Shen1,Ã, Qing Lan1 , Luoping Zhang2 , Stephen Chanock1,3 , Guilan Li4; Email: shenmi@mail.nih.gov Benzene is a recognized hematotoxicant and carcinogen that produces genotoxic and indirectly by benzene metabolites. DSB may lead to chromosome aberrations, apoptosis and hematopoietic

  12. Electronic Transitions of Protonated Benzene and Fulvene, and of C6H7 Isomers in Neon Matrices

    E-Print Network [OSTI]

    Maier, John Paul

    Electronic Transitions of Protonated Benzene and Fulvene, and of C6H7 Isomers in Neon Matrices: Electronic transitions of protonated benzene (A~ 1 B2rX~ 1 A1, origin at 325 nm) and R-protonated fulvene (A) with simple atomic and molecular species was investigated.3,4 It was found, for example, that benzene cations

  13. Charge localization and JahnTeller distortions in the benzene dimer cation Piotr A. Pieniazek, Stephen E. Bradforth,a

    E-Print Network [OSTI]

    Krylov, Anna I.

    Charge localization and Jahn­Teller distortions in the benzene dimer cation Piotr A. Pieniazek August 2008 Jahn­Teller JT distortions and charge localization in the benzene dimer cation are analyzed.1063/1.2969107 I. INTRODUCTION The benzene dimer cation is an important model system for radiation

  14. Detailed Hydration Maps of Benzene and Cyclohexane Reveal Distinct Water Structures Tanya M. Raschke* and Michael Levitt

    E-Print Network [OSTI]

    Raschke, Tanya M.

    Detailed Hydration Maps of Benzene and Cyclohexane Reveal Distinct Water Structures Tanya M of the hydrophobic solutes benzene and cyclohexane were investigated using molecular dynamics (MD) simulations O and H atoms surrounding either benzene or cyclohexane were generated from the simulation data. MD

  15. The nature of the exalted Kekule vibration of styrene and other benzene derivatives in the S1 state

    E-Print Network [OSTI]

    Haas, Yehuda

    The nature of the exalted Kekule vibration of styrene and other benzene derivatives in the S1 state vibrational frequency of several benzene derivatives in the ®rst excited state S1. It is found of benzene are treated as `twin states'. The physical nature of this vibration is discussed in view

  16. Fully ab initio atomization energy of benzene via Weizmann-2 theory Srinivasan Parthiban and Jan M. L. Martina)

    E-Print Network [OSTI]

    Martin, Jan M.L.

    Fully ab initio atomization energy of benzene via Weizmann-2 theory Srinivasan Parthiban and Jan M at absolute zero, (TAE0) of benzene, C6H6, was computed fully ab initio by means of W2h theory as 1306.6 kcal for systems the size of benzene, chemically accurate molecular atomization energies can be obtained from fully

  17. 2590 J. Am. Chem. SOC.1995,117, 2590-2599 The C-H Bond Energy of Benzene

    E-Print Network [OSTI]

    Ellison, Barney

    2590 J. Am. Chem. SOC.1995,117, 2590-2599 The C-H Bond Energy of Benzene Gustavo E. Davico ion with benzene and phenide ion with ammonia: c&6 +NH2- C6H5- +NH3. The ratio of these rate constants for derived. The enthalpy of deprotonationof benzene, the C-H bond dissociationenergy, and the electron

  18. Vacuum ultraviolet mass-analyzed threshold ionization spectroscopy of benzene: Vibrational analysis of C6H6

    E-Print Network [OSTI]

    Kim, Myung Soo

    Vacuum ultraviolet mass-analyzed threshold ionization spectroscopy of benzene: Vibrational analysis-photon spectra agrees with the previous suggestion that the geometry of benzene cation in the ground electronic. INTRODUCTION Benzene cation has been the focus of an intensive re- search effort, both experimental1

  19. Location of MTBE and toluene in the channel system of the zeolite mordenite: Adsorption and host-guest interactions

    SciTech Connect (OSTI)

    Arletti, Rossella, E-mail: rossella.arletti@unito.it [Department of Earth Sciences, University of Torino Via Valperga Caluso 35, I-10125, Torino (Italy)] [Department of Earth Sciences, University of Torino Via Valperga Caluso 35, I-10125, Torino (Italy); Martucci, Annalisa; Alberti, Alberto [Department of Earth Sciences, University of Ferrara, Via G. Saragat 1, I-44100, Ferrara (Italy)] [Department of Earth Sciences, University of Ferrara, Via G. Saragat 1, I-44100, Ferrara (Italy); Pasti, Luisa; Nassi, Marianna [Department of Chemistry, University of Ferrara, Via L. Borsari 26, I-44100 Ferrara (Italy)] [Department of Chemistry, University of Ferrara, Via L. Borsari 26, I-44100 Ferrara (Italy); Bagatin, Roberto [Research Centre for Non-Conventional Energy-Istituto ENI Donegani, Environmental Technologies, Via Fauser 4, I-28100 Novara (Italy)] [Research Centre for Non-Conventional Energy-Istituto ENI Donegani, Environmental Technologies, Via Fauser 4, I-28100 Novara (Italy)

    2012-10-15T23:59:59.000Z

    This paper reports a study of the location of Methyl Tertiary Butyl Ether (MTBE) and toluene molecules adsorbed in the pores of the organophylic zeolite mordenite from an aqueous solution. The presence of these organic molecules in the zeolite channels was revealed by structure refinement performed by the Rietveld method. About 3 molecules of MTBE and 3.6 molecules of toluene per unit cell were incorporated into the cavities of mordenite, representing 75% and 80% of the total absorption capacity of this zeolite. In both cases a water molecule was localized inside the side pocket of mordenite. The saturation capacity determined by the adsorption isotherms, obtained by batch experiments, and the weight loss given by thermogravimetric (TG) analyses were in very good agreement with these values. The interatomic distances obtained after the structural refinements suggest MTBE could be connected to the framework through a water molecule, while toluene could be bonded to framework oxygen atoms. The rapid and high adsorption of these hydrocarbons into the organophylic mordenite zeolite makes this cheap and environmental friendly material a suitable candidate for the removal of these pollutants from water. - graphical abstract: Location of MTBE (a) and toluene (b) in mordenite channels (projection along the [001] direction). Highlights: Black-Right-Pointing-Pointer We investigated the MTBE and toluene adsorption process into an organophilic zeolite mordenite. Black-Right-Pointing-Pointer The presence of MTBE and toluene in mordenite was determined by X-ray diffraction studies. Black-Right-Pointing-Pointer About 3 molecules of MTBE and 3.6 molecules of toluene per unit cell were incorporated into the zeolite cavities. Black-Right-Pointing-Pointer MTBE is connected to the framework through a water molecule. Black-Right-Pointing-Pointer Toluene is directly bonded to framework oxygen atoms.

  20. J. Am. Chem. SOC.1987, 109, 6825-6836 6825 `H NMR (22 O C , benzene-d6): 6 3.26 (s, OSCMe), 3.03 (s, 2JwH=

    E-Print Network [OSTI]

    Prentiss, Mara

    J. Am. Chem. SOC.1987, 109, 6825-6836 6825 `H NMR (22 O C , benzene-d6): 6 3.26 (s, OSCMe), 3.03 (s to yield a yellow powder (0.35 g, 92%). `H NMR (22 O C , benzene-d6): 6 2.66 (s, bridge 02CNMe2),2.59 (s of C 0 2was reacted with W,Bz;(NMe,),. `H NMR (22 OC. benzene-dr): 6 3.79 (s, CH,Ph), 2.67, 2.28 S, 02

  1. Isothermal vapor-liquid equilibria for benzene + cyclohexane + 1-propanol and for three constituent binary systems

    SciTech Connect (OSTI)

    Kurihara, Kiyofumi; Uchiyama, Masanori; Kojima, Kazuo [Nihon Univ., Tokyo (Japan). Dept. of Industrial Chemistry] [Nihon Univ., Tokyo (Japan). Dept. of Industrial Chemistry

    1997-01-01T23:59:59.000Z

    Isothermal vapor-liquid equilibria were measured for the ternary system of benzene + cyclohexane + 1-propanol and its constituent binary systems of benzene + cyclohexane, cyclohexane + 1-propanol, and benzene + 1-propanol at 323.15 and 333.15 K, using the apparatus proposed in a previous study. The experimental binary data were correlated using the NRTL equation. The ternary system was predicted using the binary NRTL parameters. The average absolute percent deviations between the predicted and experimental ternary total pressures are 0.5% at 323.15 K and 0.4% at 333.15 K.

  2. Bond Energy Sums in Benzene, Cyclohexatriene and Cyclohexane Prove Resonance Unnecessary

    E-Print Network [OSTI]

    Raji Heyrovska

    2008-07-27T23:59:59.000Z

    The recent new structure of benzene shows that it consists of three C atoms of radii as in graphite alternating with three C atoms with double bond radii. This is different from the hypothetical cyclohexatriene (Kekule structure) involving alternate double and single bonds. It was shown that the difference in the bond energy sum of the atomic structure of benzene from that of the Kekule structure is the energy (erroneously) assumed to be due to resonance. Here it is shown that the present structure of benzene also explains the energy of hydrogenation into cyclohexane and its difference from that of cyclohexatriene.

  3. Resonant ion-dip infrared spectroscopy of benzene(methanol)m clusters R. Nathaniel Pribble, Fredrick C. Hagemeister, and Timothy S. Zwiera)

    E-Print Network [OSTI]

    Zwier, Timothy S.

    Resonant ion-dip infrared spectroscopy of benzene­(methanol)m clusters with m 1­6 R. Nathaniel bonding between benzene and methanol. The m 2 spectrum features two strong transitions at 3506 and 3605 cm in the absence of benzene, is redshifted by 76 cm 1 due to a strengthened hydrogen bond. In benzene­ CH3OH 3

  4. COSMIC-RAY-MEDIATED FORMATION OF BENZENE ON THE SURFACE OF SATURN'S MOON TITAN

    SciTech Connect (OSTI)

    Zhou Li; Zheng Weijun; Kaiser, Ralf I. [Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI (United States); Landera, Alexander; Mebel, Alexander M. [Department of Chemistry and Biochemistry, Florida International University, Miami, FL (United States); Liang, Mao-Chang [Research Center for Environmental Changes, Academia Sinica, Taipei, Taiwan (China); Yung, Yuk L. [Division of Geological and Planetary Sciences, Caltech, Pasadena, CA (United States)

    2010-08-01T23:59:59.000Z

    The aromatic benzene molecule (C{sub 6}H{sub 6})-a central building block of polycyclic aromatic hydrocarbon molecules-is of crucial importance for the understanding of the organic chemistry of Saturn's largest moon, Titan. Here, we show via laboratory experiments and electronic structure calculations that the benzene molecule can be formed on Titan's surface in situ via non-equilibrium chemistry by cosmic-ray processing of low-temperature acetylene (C{sub 2}H{sub 2}) ices. The actual yield of benzene depends strongly on the surface coverage. We suggest that the cosmic-ray-mediated chemistry on Titan's surface could be the dominant source of benzene, i.e., a factor of at least two orders of magnitude higher compared to previously modeled precipitation rates, in those regions of the surface which have a high surface coverage of acetylene.

  5. DYNAMIC MODELING AND CONTROL OF REACTIVE DISTILLATION FOR HYDROGENATION OF BENZENE 

    E-Print Network [OSTI]

    Aluko, Obanifemi

    2010-01-16T23:59:59.000Z

    This work presents a modeling and control study of a reactive distillation column used for hydrogenation of benzene. A steady state and a dynamic model have been developed to investigate control structures for the column. The most important aspects...

  6. Numerical analysis of the effect of acetylene and benzene addition to low-pressure benzene-rich flat flames on polycyclic aromatic hydrocarbon formation

    SciTech Connect (OSTI)

    Kunioshi, Nilson [Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Komori, Seisaku [6th Group, Central Research Laboratory, Hamamatsu Photonics K. K. 500 Hirakuchi, Hamakita City, Shizuoka 434-8601 (Japan); Fukutani, Seishiro [Department of System Engineering, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197 (Japan)

    2006-10-15T23:59:59.000Z

    A modification of the CHEMKIN II package has been proposed for modeling addition of an arbitrary species at an arbitrary temperature to an arbitrary distance from the burner along a flat flame. The modified program was applied to the problem of addition of acetylene or benzene to different positions of a 40-Torr, {phi}=2.4 benzene/O{sub 2}/40%-N{sub 2} premixed flame to reach final equivalence ratios of {phi}=2.5 and 2.681. The results obtained showed that acetylene addition to early positions of the flame led to significant increase in pyrene production rates, but pyrene concentrations were lower in the flames with acetylene addition in both the {phi}=2.5 and 2.681 cases. Addition of benzene to the flame did not alter pyrene production rates in either the {phi}=2.5 or 2.681 cases; however, for {phi}=2.5, pyrene concentrations increased with benzene addition, while for {phi}=2.681, pyrene contents decreased in comparison to the correspondent flames with no addition. Acetylene addition led to a significant increase in pyrene production rates, but the pyrene levels dropped due to increase in the flow velocity. Pyrene production rates were not sensitive to benzene addition, but pyrene contents increased with benzene addition when the flow velocity decreased. These results show that PAH concentration changes accompanying species addition to flames should be interpreted carefully, because an increase or decrease in the content of a PAH species does not necessarily reflect an effect on its formation rate or mechanism. (author)

  7. Diffusion of benzene confined in the oriented nanochannels of chrysotile asbestos fibers

    SciTech Connect (OSTI)

    Mamontov, E. [NIST Center for Neutron Research, National Institute of Standards and Technology, 100 Bureau Dr., MS 8562, Gaithersburg, Maryland 20899-8562 (United States); Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742-2115 (United States); Kumzerov, Yu.A.; Vakhrushev, S.B. [Ioffe Physico-Technical Institute, 194021 St. Petersburg (Russian Federation)

    2005-11-01T23:59:59.000Z

    We used quasielastic neutron scattering to study the dynamics of benzene that completely fills the nanochannels of chrysotile asbestos fibers with a characteristic diameter of about 5 nm. The macroscopical alignment of the nanochannels in fibers provided an interesting opportunity to study anisotropy of the dynamics of confined benzene by means of collecting the data with the scattering vector either parallel or perpendicular to the fibers axes. The translational diffusive motion of benzene molecules was found to be isotropic. While bulk benzene freezes at 278.5 K, we observed the translational dynamics of the supercooled confined benzene on the time scale of hundreds of picoseconds even below 200 K, until at about 160 K its dynamics becomes too slow for the {mu}eV resolution of the neutron backscattering spectrometer. The residence time between jumps for the benzene molecules measured in the temperature range of 260 K to 320 K demonstrated low activation energy of 2.8 kJ/mol.

  8. Multiple solutions of CCD equations for PPP model of benzene

    E-Print Network [OSTI]

    Podeszwa, R; Jankowski, K; Rubiniec, K; Podeszwa, Rafa{\\l}; Stolarczyk, Leszek Z.; Jankowski, Karol; Rubiniec, Krzysztof

    2002-01-01T23:59:59.000Z

    To gain some insight into the structure and physical significance of the multiple solutions to the coupled-cluster doubles (CCD) equations corresponding to the Pariser-Parr-Pople (PPP) model of cyclic polyenes, complete solutions to the CCD equations for the A^{-}_{1g} states of benzene are obtained by means of the homotopy method. By varying the value of the resonance integral beta from -5.0 eV to -0.5 eV, we cover the so-called weakly, moderately, and strongly correlated regimes of the model. For each value of beta 230 CCD solutions are obtained. It turned out, however, that only for a few solutions a correspondence with some physical states can be established. It has also been demonstrated that, unlike for the standard methods of solving CCD equations, some of the multiple solutions to the CCD equations can be attained by means of the iterative process based on Pulay's direct inversion in the iterative subspace (DIIS) approach.

  9. Test of electron beam technology on Savannah River Laboratory low-activity aqueous waste for destruction of benzene, benzene derivatives, and bacteria

    SciTech Connect (OSTI)

    Dougal, R.A. [Univ. of South Carolina, Columbia, SC (United States). Dept. of Electrical and Computer Engineering

    1993-08-01T23:59:59.000Z

    High energy radiation was studied as a means for destroying hazardous organic chemical wastes. Tests were conducted at bench scale with a {sup 60}Co source, and at full scale (387 l/min) with a 1.5 MV electron beam source. Bench scale tests for both benzene and phenol included 32 permutations of water quality factors. For some water qualities, as much as 99.99% of benzene or 90% of phenol were removed by 775 krads of {sup 60}Co irradiation. Full scale testing for destruction of benzene in a simulated waste-water mix showed loss of 97% of benzene following an 800 krad dose and 88% following a 500 krad dose. At these loss rates, approximately 5 Mrad of electron beam irradiation is required to reduce concentrations from 100 g/l to drinking water quality (5 {mu}g/l). Since many waste streams are also inhabited by bacterial populations which may affect filtering operations, the effect of irradiation on those populations was also studied. {sup 60}Co and electron beam irradiation were both lethal to the bacteria studied at irradiation levels far lower than were necessary to remove organic contaminants.

  10. Interaction of toluene with two-color asymmetric laser fields: Controlling the directional emission of molecular hydrogen fragments

    SciTech Connect (OSTI)

    Kaziannis, S.; Kotsina, N.; Kosmidis, C. [Department of Physics, Atomic and Molecular Physics Laboratory, University of Ioannina, University Campus, Ioannina GR-45110 (Greece)

    2014-09-14T23:59:59.000Z

    The interaction of toluene with strong asymmetric two-color laser irradiation of 40 fs duration is studied by means of Time of flight mass spectrometry. Highly energetic H{sub 2}{sup +} and H{sub 3}{sup +} fragment ions are produced through an isomerization process taking place within transient multiply charged parent ions. Comparative study of deuterium labeled toluene isotopes enables the discrimination between molecular hydrogen fragments formed exclusively within the CH{sub 3}- part from those that require hydrogen atom exchange between the former and the phenyl moiety. It is demonstrated that by manipulating the relative phase of the ?/2? field components the selective ionization of oriented toluene molecules can be used as a tool to control the directional emission of the H{sub 2}{sup +}, H{sub 3}{sup +} species.

  11. Low Energy Barrier Proton Transfer in Protonated Benzene-Water Complex Eugene S. Kryachko and Minh Tho Nguyen*

    E-Print Network [OSTI]

    Nguyen, Minh Tho

    Low Energy Barrier Proton Transfer in Protonated Benzene-Water Complex Eugene S. Kryachko and Minh-bonded benzene-water complex is studied at the MP2/6-31+G(d,p) computational level. It is shown that, contrary to the fact that benzene is more basic than water by 13.5 kcal/mol, the excess proton favors to reside

  12. In utero exposure to benzene increases embryonic c-Myb and Pim-1 protein levels in CD-1 mice

    SciTech Connect (OSTI)

    Wan, Joanne [Department of Pharmacology and Toxicology, Queen's University, Kingston, Ontario, K7L 3N6 (Canada); Winn, Louise M. [Department of Pharmacology and Toxicology, Queen's University, Kingston, Ontario, K7L 3N6 (Canada); School of Environmental Studies, Queen's University, Kingston, Ontario, K7L 3N6 (Canada)], E-mail: winnl@queensu.ca

    2008-05-01T23:59:59.000Z

    Benzene is a known human leukemogen, but its role as an in utero leukemogen remains controversial. Epidemiological studies have correlated parental exposure to benzene with an increased incidence of childhood leukemias. We hypothesize that in utero exposure to benzene may cause leukemogenesis by affecting the embryonic c-Myb/Pim-1 signaling pathway and that this is mediated by oxidative stress. To investigate this hypothesis, pregnant CD-1 mice were treated with either 800 mg/kg of benzene or corn oil (i.p.) on days 10 and 11 of gestation and in some cases pretreated with 25 kU/kg of PEG-catalase. Phosphorylated and total embryonic c-Myb and Pim-1 protein levels were assessed using Western blotting and maternal and embryonic oxidative stress were assessed by measuring reduced to oxidized glutathione ratios. Our results show increased oxidative stress at 4 and 24 h after exposure, increased phosphorylated Pim-1 protein levels 4 h after benzene exposure, and increased Pim-1 levels at 24 and 48 h after benzene exposure. Embryonic c-Myb levels were elevated at 24 h after exposure. PEG-catalase pretreatment prevented benzene-mediated increases in embryonic c-Myb and Pim-1 protein levels, and benzene-induced oxidative stress. These results support a role for ROS in c-Myb and Pim-1 alterations after in utero benzene exposure.

  13. Dissociation of the benzene molecule by UV and soft X-rays in circumstellar environment

    E-Print Network [OSTI]

    H. M. Boechat-Roberty; R. Neves; S. Pilling; A. F. Lago; G. G. B. de Souza

    2008-11-30T23:59:59.000Z

    Benzene molecules, present in the proto-planetary nebula CRL 618, are ionized and dissociated by UV and X-ray photons originated from the hot central star and by its fast wind. Ionic species and free radicals produced by these processes can lead to the formation of new organic molecules. The aim of this work is to study the photoionization and photodissociation processes of the benzene molecule, using synchrotron radiation and time of flight mass spectrometry. Mass spectra were recorded at different energies corresponding to the vacuum ultraviolet (21.21 eV) and soft X-ray (282-310 eV) spectral regions. The production of ions from the benzene dissociative photoionization is here quantified, indicating that C6H6 is more efficiently fragmented by soft X-ray than UV radiation, where 50% of the ionized benzene molecules survive to UV dissociation while only about 4% resist to X-rays. Partial ion yields of H+ and small hydrocarbons such as C2H2+, C3H3+ and C4H2+ are determined as a function of photon energy. Absolute photoionization and dissociative photoionization cross sections have also been determined. From these values, half-life of benzene molecule due to UV and X-ray photon fluxes in CRL 618 were obtained.

  14. Hydrogen-terminated silicon nanowire photocatalysis: Benzene oxidation and methyl red decomposition

    SciTech Connect (OSTI)

    Lian, Suoyuan [Institute of Functional Nano and Soft Materials and Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123 (China) [Institute of Functional Nano and Soft Materials and Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123 (China); School of Chemical Engineering and Materials, Dalian Polytechnic University, Dalian 116034 (China); Tsang, Chi Him A. [Institute of Functional Nano and Soft Materials and Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123 (China) [Institute of Functional Nano and Soft Materials and Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123 (China); Centre of Super Diamond and Advanced Films, City University of Hong Kong, Hong Kong (China); Kang, Zhenhui, E-mail: zhkang@suda.edu.cn [Institute of Functional Nano and Soft Materials and Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123 (China)] [Institute of Functional Nano and Soft Materials and Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123 (China); Liu, Yang, E-mail: yangl@suda.edu.cn [Institute of Functional Nano and Soft Materials and Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123 (China)] [Institute of Functional Nano and Soft Materials and Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123 (China); Wong, Ningbew [Centre of Super Diamond and Advanced Films, City University of Hong Kong, Hong Kong (China)] [Centre of Super Diamond and Advanced Films, City University of Hong Kong, Hong Kong (China); Lee, Shuit-Tong [Institute of Functional Nano and Soft Materials and Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123 (China) [Institute of Functional Nano and Soft Materials and Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123 (China); Centre of Super Diamond and Advanced Films, City University of Hong Kong, Hong Kong (China)

    2011-12-15T23:59:59.000Z

    Graphical abstract: H-SiNWs can catalyze hydroxylation of benzene and degradation of methyl red under visible light irradiation. Highlights: Black-Right-Pointing-Pointer Hydrogen-terminated silicon nanowires were active photocatalyst in the hydroxylation of benzene under light. Black-Right-Pointing-Pointer Hydrogen-terminated silicon nanowires were also effective in the decomposition of methyl red dye. Black-Right-Pointing-Pointer The Si/SiO{sub x} core-shell structure is the main reason of the obtained high selectivity during the hydroxylation. -- Abstract: Hydrogen-terminated silicon nanowires (H-SiNWs) were used as heterogeneous photocatalysts for the hydroxylation of benzene and for the decomposition of methyl red under visible light irradiation. The above reactions were monitored by GC-MS and UV-Vis spectrophotometry, respectively, which shows 100% selectivity for the transformation of benzene to phenol. A complete decomposition of a 2 Multiplication-Sign 10{sup -4} M methyl red solution was achieved within 30 min. The high selectivity for the hydroxylation of benzene and the photodecomposition demonstrate the catalytic activity of ultrafine H-SiNWs during nanocatalysis.

  15. Total cross sections for positron scattering from benzene, cyclohexane, and aniline

    SciTech Connect (OSTI)

    Zecca, Antonio; Moser, Norberto; Perazzolli, Chiara; Salemi, Alessandro [Department of Physics, University of Trento, I-38050 Povo (Trento) (Italy); Brunger, Michael J. [ARC Centre for Antimatter-Matter Studies, School of Chemistry, Physics and Earth Sciences, Flinders University, G.P.O. Box 2100, Adelaide, South Australia 5001 (Australia)

    2007-08-15T23:59:59.000Z

    We use a linear transmission technique to measure total cross sections for positron scattering from benzene, cyclohexane, and aniline. In the case of cyclohexane, the energy range of the present study is 0.1-20 eV, while for benzene and aniline it is 0.2-20 eV. With respect to benzene and cyclohexane, comparison is made to the only other existing results we know of [Makochekanwa and co-workers, Phys. Rev. A 68, 032707 (2003); 72, 042705 (2005)]. Agreement with those data is only marginal, being particularly poor at the overlap lower energies. Unlike Kimura et al. [J. Phys. B 37, 1461 (2004)], we find the low-energy dependence of the positron-benzene total cross sections to be qualitatively similar to those found in the electron channel [Gulley et al., J. Phys. B 31, 2735 (1998)]. We believe that the present positron-aniline total cross sections represent the first time such data have been measured. These cross sections are almost identical to those we found for benzene, suggesting that substitution of hydrogen by the amine group on the aromatic ring is largely irrelevant to the scattering process in the energy regimes considered.

  16. THE INFLUENCE OF BENZENE AS A TRACE REACTANT IN TITAN AEROSOL ANALOGS

    SciTech Connect (OSTI)

    Trainer, Melissa G. [Planetary Environments Laboratory, Code 699, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Sebree, Joshua A. [NASA Postdoctoral Program Fellow, Code 699, Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Heidi Yoon, Y.; Tolbert, Margaret A., E-mail: melissa.trainer@nasa.gov [Cooperative Institute for Research in Environmental Sciences, University of Colorado at Boulder, Box 216 UCB, Boulder, CO 80309 (United States)

    2013-03-20T23:59:59.000Z

    Benzene has been detected in Titan's atmosphere by Cassini instruments, with concentrations ranging from sub-ppb in the stratosphere to ppm in the ionosphere. Sustained levels of benzene in the haze formation region could signify that it is an important reactant in the formation of Titan's organic aerosol. To date, there have not been laboratory investigations to assess the influence of benzene on aerosol properties. We report a laboratory study on the chemical composition of organic aerosol formed from C{sub 6}H{sub 6}/CH{sub 4}/N{sub 2} via far ultraviolet irradiation (120-200 nm). The compositional results are compared to those from aerosol generated by a more ''traditional Titan'' mixture of CH{sub 4}/N{sub 2}. Our results show that even a trace amount of C{sub 6}H{sub 6} (10 ppm) has significant impact on the chemical composition and production rates of organic aerosol. There are several pathways by which photolyzed benzene may react to form larger molecules, both with and without the presence of CH{sub 4}, but many of these reaction mechanisms are only beginning to be explored for the conditions at Titan. Continued work investigating the influence of benzene in aerosol growth will advance understanding of this previously unstudied reaction system.

  17. Economic analysis: impact of CS/R process on benzene market

    SciTech Connect (OSTI)

    Spielberger, L.; Klein, J.

    1981-05-01T23:59:59.000Z

    Contract No. DE-AC01-78ET10159 (formerly ET-78-C-01-3117) between UOP/SDC and the United States Department of Energy (DOE) requires UOP/SDC to provide specific engineering and technical services to the DOE Office of Coal Processing in support of the Coal Gasification Program. This report covers an economic study on the projected price of benzene through the next decade based on the market factors and production costs. The impact of the CS/R process on the benzene market was evaluated. In addition, the cost of gas from the CS/R process was determined as a function of the byproduct credit for benzene.

  18. Vapor-liquid equilibria for the system benzene-thiophene-methanol

    SciTech Connect (OSTI)

    Triday, J.O.; Rodriguez, P.

    1985-01-01T23:59:59.000Z

    Isothermal vapor pressure data over the whole range of composition were obtained for the system benzene-thiophene-methanol. Data were taken at temperatures of 35, 40, and 45 /sup 0/C by using a static equilibrium cell. The systems benzene-methanol and thiophene-methanol are highly nonideal, while the system benzene-thiophene shows a very small deviation from ideality. The models suggested by Wilson and by Renon and Prausnitz (NRTL) and the modified equation of Abrams and Prausnitz (UNIQUAC) were used in the reduction of data. Physical parameters of these equations obtained from the binary data were used to predict the ternary system. The Wilson equation gives the best fit for the binary as well as the ternary data. Also, this equation gives the best prediction for the ternary system.

  19. Benzene Adsorbed on Metals: Concerted Effect of Covalency and van der Waals Bonding

    E-Print Network [OSTI]

    Liu, Wei; Santra, Biswajit; Michaelides, Angelos; Scheffler, Matthias; Tkatchenko, Alexandre

    2012-01-01T23:59:59.000Z

    The adsorption of aromatic molecules on metal surfaces plays a key role in condensed matter physics and functional materials. Depending on the strength of the interaction between the molecule and the surface, the binding is typically classified as either physisorption or chemisorption. Van der Waals (vdW) interactions contribute significantly to the binding in physisorbed systems, but the role of the vdW energy in chemisorbed systems remains unclear. Here we study the interaction of benzene with the (111) surface of transition metals, ranging from weak adsorption (Ag and Au) to strong adsorption (Pt, Pd, Ir, and Rh). When vdW interactions are accurately accounted for, the barrier to adsorption predicted by standard density functional calculations essentially vanishes, producing a metastable precursor state on Pt and Ir surfaces. Notably, vdW forces contribute more to the binding of covalently bonded benzene than they do when benzene is physisorbed.

  20. Theoretical study of reactions of HO{sub 2} in low-temperature oxidation of benzene

    SciTech Connect (OSTI)

    Altarawneh, Mohammednoor [Chemical Engineering Department, Al-Hussein Bin Talal University, Ma'an (Jordan); Dlugogorski, Bogdan Z.; Kennedy, Eric M.; Mackie, John C. [Process Safety and Environment Protection Research Group, School of Engineering, The University of Newcastle, Callaghan, NSW 2308 (Australia)

    2010-07-15T23:59:59.000Z

    We have generated a set of thermodynamic and kinetic parameters for the reactions involving HO{sub 2} in the very early stages of benzene oxidation at low temperatures using density functional theory (DFT). In particular, we report the rate constants for the reactions of HO{sub 2} with benzene and phenyl. The calculated reaction rate constant for the abstraction of H-C{sub 6}H{sub 5} by HO{sub 2} is found to be in good agreement with the limited experimental values. HO{sub 2} addition to benzene is found to be more important than direct abstraction. We show that the reactions of HO{sub 2} with the phenyl radical generate the propagating radical OH in a highly exoergic reaction. The results presented herein should be useful in modeling the oxidation of aromatic compounds at low temperatures. (author)

  1. In utero and in vitro effects of benzene and its metabolites on erythroid differentiation and the role of reactive oxygen species

    SciTech Connect (OSTI)

    Badham, Helen J. [Department of Pharmacology and Toxicology. Queen's University, Kingston, Ontario, K7L 3N6 (Canada); Winn, Louise M., E-mail: winnl@queensu.c [Department of Pharmacology and Toxicology. Queen's University, Kingston, Ontario, K7L 3N6 (Canada); School of Environmental Studies, Queen's University, Kingston, Ontario, K7L 3N6 (Canada)

    2010-05-01T23:59:59.000Z

    Benzene is a ubiquitous occupational and environmental toxicant. Exposures to benzene both prenatally and during adulthood are associated with the development of disorders such as aplastic anemia and leukemia. Mechanisms of benzene toxicity are unknown; however, generation of reactive oxygen species (ROS) by benzene metabolites may play a role. Little is known regarding the effects of benzene metabolites on erythropoiesis. Therefore, to determine the effects of in utero exposure to benzene on the growth and differentiation of fetal erythroid progenitor cells (CFU-E), pregnant CD-1 mice were exposed to benzene and CFU-E numbers were assessed in fetal liver (hematopoietic) tissue. In addition, to determine the effect of benzene metabolite-induced ROS generation on erythropoiesis, HD3 chicken erythroblast cells were exposed to benzene, phenol, or hydroquinone followed by stimulation of erythrocyte differentiation. Our results show that in utero exposure to benzene caused significant alterations in female offspring CFU-E numbers. In addition, exposure to hydroquinone, but not benzene or phenol, significantly reduced the percentage of differentiated HD3 cells, which was associated with an increase in ROS. Pretreatment of HD3 cells with polyethylene glycol-conjugated superoxide dismutase (PEG-SOD) prevented hydroquinone-induced inhibition of erythropoiesis, supporting the hypothesis that ROS generation is involved in the development of benzene erythrotoxicity. In conclusion, this study provided evidence that ROS generated as a result of benzene metabolism may significantly alter erythroid differentiation, potentially leading to the development of Blood Disorders.

  2. Catalytic and stoichiometric bromination of aromatic compounds in aqueous trifluoroacetic acid in the presence of nitrogen-containing oxidizing agents

    SciTech Connect (OSTI)

    Cheprakov, A.V.; Makhon'kov, D.I.; Rodkin, M.A.; Beletskaya, I.P.

    1988-07-10T23:59:59.000Z

    The mono- and polybromination of benzene, halogenobenzenes, toluene, p-xylene, anisole, biphenyl, benzotrifluoride, benzoic acid, p-nitro- and p-carboxytoluene, p-methoxybenzonitrile, tetralin, and naphthalene were studied in trifluoroacetic acid and its aqueous solutions in systems containing stoichiometric amounts of bromine or alkali-metal bromide and stoichiometric or catalytic (in the presence of oxygen or air) amounts of nitrogen-containing oxidizing agent (nitrogen(IV) oxide, alkali-metal nitrate or nitrite). It is suggested that the brominating agent under the investigated conditions is nitryl bromide NO/sub 2/Br. Under the conditions of catalytic bromination anthracene is oxidized to anthraquinone with a preparative yield.

  3. Evaluation and Optimization of MTBE Biodegradation in Aquifers, Final Report

    SciTech Connect (OSTI)

    Legler, T; Balser, L; Koester, C; Wilson, W

    2004-02-13T23:59:59.000Z

    This study was focused on meeting the following objectives concerning the process of methyl tertiary butyl ether (MTBE) biodegradation, with the goal of optimizing this process in situ: 1. Assess whether intrinsic bioattenuation of MTBE is feasible under aerobic conditions across several contaminated sites. 2. Determine the effect of co-contaminants, specifically water-soluble gasoline components (most notably benzene, toluene, ethylbenzene and xylenes [BTEX]) on MTBE biodegradation. 3. Determine whether microbial and/or chemical factors contribute to different MTBE degradative activities. 4. Isolate and characterize MTBE-degrading microorganisms from sediments in which MTBE biodegradation was observed.

  4. Secondary battery containing zinc electrode with modified separator and method

    DOE Patents [OSTI]

    Poa, D.S.

    1984-02-16T23:59:59.000Z

    A battery containing a zinc electrode with a porous separator between the anode and cathode. The separator is a microporous substrate carrying therewith an organic solvent of benzene, toluene or xylene with a tertiary organic amine therein, wherein the tertiary amine has three carbon chains each containing from six to eight carbon atoms. The separator reduces the rate of zinc dentrite growth in the separator during battery operation prolonging battery life by preventing short circuits. A method of making the separator is also disclosed.

  5. Secondary battery containing zinc electrode with modified separator and method

    DOE Patents [OSTI]

    Poa, David S. (Naperville, IL); Yao, Neng-Ping (Clarendon Hills, IL)

    1985-01-01T23:59:59.000Z

    A battery containing a zinc electrode with a porous separator between the anode and cathode. The separator is a microporous substrate carrying therewith an organic solvent of benzene, toluene or xylene with a tertiary organic amine therein, wherein the tertiary amine has three carbon chains each containing from six to eight carbon atoms. The separator reduces the rate of zinc dentrite growth in the separator during battery operation prolonging battery life by preventing short circuits. A method of making the separator is also disclosed.

  6. 2003 NaturePublishing Group GC/MSD after extraction of the 3-ml cultures with toluene, gentle concentration and

    E-Print Network [OSTI]

    Pilastro, Andrea

    © 2003 NaturePublishing Group GC/MSD after extraction of the 3-ml cultures with toluene, gentle. Dehalococcoides sp. strain CBDB1 was cultivated under anaerobic conditions with a gas phase of 20% CO2/80% N2% and 76% with the coats. The cultures were supplied with 5 mM acetate and hydrogen (2.5 ml injected

  7. Surfactant loss control in chemical flooding: Spectroscopic and calorimetric study of adsorption and precipitation on reservoir minerals. [Alkyl phenoxy polyoxyether type nonionic surfactants and anionic meta xylene sulfonates

    SciTech Connect (OSTI)

    Somasundaran, P.

    1993-02-01T23:59:59.000Z

    The aim of this project is to elucidate the mechanisms of adsorption and surface precipitation of flooding surfactants on reservoir minerals. Effect of surfactant structure, surfactant combinations and other inorganic and polymeric species will also be determined using solids of relevant mineralogy. A multi-pronged approach consisting of micro nano spectroscopy, microcalorimetry, electrokinetics, surface tension and wettability will be used to achieve the goals. The results of this study should help in controlling surfactant loss in chemical flooding and also in developing optimum structures and conditions for efficient chemical flooding processes. Adsorption of selected individual surfactants on oxide minerals was determined. The aim was to characterize the microstructure of the adsorbed layers. Work was began with alkyl phenoxy polyoxyether type nonionic surfactants and anionic meta xylene sulfonates.

  8. Mechanism reduction for multicomponent surrogates: a case study using toluene reference fuels

    E-Print Network [OSTI]

    Niemeyer, Kyle E

    2014-01-01T23:59:59.000Z

    Strategies and recommendations for performing skeletal reductions of multicomponent surrogate fuels are presented, through the generation and validation of skeletal mechanisms for a three-component toluene reference fuel. Using the directed relation graph with error propagation and sensitivity analysis method followed by a further unimportant reaction elimination stage, skeletal mechanisms valid over comprehensive and high-temperature ranges of conditions were developed at varying levels of detail. These skeletal mechanisms were generated based on autoignition simulations, and validation using ignition delay predictions showed good agreement with the detailed mechanism in the target range of conditions. When validated using phenomena other than autoignition, such as perfectly stirred reactor and laminar flame propagation, tight error control or more restrictions on the reduction during the sensitivity analysis stage were needed to ensure good agreement. In addition, tight error limits were needed for close pr...

  9. The conductivity and dielectric behavior of solutions of bitumen in toluene

    SciTech Connect (OSTI)

    Chow, R.S.; Tse, D.L.; Takamura, K.

    1988-06-01T23:59:59.000Z

    Previous work on the conductivity and dielectric behavior of residual oil (the fraction remaining in the distillation tower) has suggested that the asphaltene fraction (pentane insolubles) was responsible for the conductivity behavior of solutions of this oil in organic solvents. In this work it is shown that the asphaltenes in heavy crude oils determine the conductivity behavior of solutions of the bulk oil in toluene, while the dielectric behavior is influenced by each component of the oil. The strong dependence of the conductivity on the asphaltene fraction makes it possible to determine the asphaltene content of a heavy crude oil by a conductimetric technique. The conductivity and dielectric behavior of crude oils and fractions of the crude oils, as well as the technique for determining the asphaltene content by conductivity will be presented.

  10. Determination of a peak benzene exposure to consumers at typical self-service gasoline stations

    E-Print Network [OSTI]

    Carapezza, Ted

    1977-01-01T23:59:59.000Z

    the public exposure to benzene at the self-serv1ce gas pump seems of paramount importance dur1ng this time of the highly publicized benzene hazard and increased gasoline consumption. These factors produced the amtivating effect for th1s research effort wh... Table ~Pa e I. HUMAN INHALATION EXPOSURE TO GASOLINE VAPOR. I I. SELF-SERVICE GASOLINE STATIONS . III. SAMPLING RESULTS IV. FIELD DATA: STATION I V. FIELD DATA: STATION II VI. FIEI D DATA: STATION III. VI I. FIELD DATA: STATION IV . VIII...

  11. Modeling the natural attenuation of benzene in groundwater impacted by ethanol-blended fuels: Effect of ethanol content

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    Modeling the natural attenuation of benzene in groundwater impacted by ethanol-blended fuels: Effect of ethanol content on the lifespan and maximum length of benzene plumes Diego E. Gomez1 and Pedro 10 March 2009. [1] A numerical model was used to evaluate how the concentration of ethanol

  12. 40 CFR Ch. I (7105 Edition)Pt. 194 1,2,4-Trichlorobenzene (Benzene, 1,2,4-

    E-Print Network [OSTI]

    36 40 CFR Ch. I (7­1­05 Edition)Pt. 194 Toxaphene 1,2,4-Trichlorobenzene (Benzene, 1,2,4- trichloro (Benzene, 1,3,5-trinitro-) Tris(1-aziridinyl)phosphine sulfide (Aziridine, 1,1,1phosphinothioylidyne

  13. Anhydrous aluminum chloride as an alkylation catalyst: identification of mono- and dialkyl-benzenes from the condensation of tertiary butyl alcohol with benzene.

    E-Print Network [OSTI]

    Scoggins, Lacey E

    1959-01-01T23:59:59.000Z

    LIBRARY a a w c"I. I. SI - O~ TI:YAf ANHYDROUS ALUMINUM CHLORIDE AS AN ALKYLATION CATALYST: IDENTIFICATION OF MONO- AND DIALKYIZENZENES FROM THE CONDENSATION QF TERTIARY BUTYL ALCOHOL WITH BENKENE IACEY EUGENE SCOGGINS 4 A Thesis Submitted...: IDENTIFICATION OF MONO- AND DI~NZZNES FROM THE CONDENSATION OF TERTIARY BUTYL ALCOHOL WITH BENZENE A Thesis By LACEY EUGENE SCOGGINS Approved as to style and content hy: Chairman of Committee Head of Chemistry Department 1959 ACKNOWLEDGME1VTS The author...

  14. Kinetics and modeling of mixture effects during complete catalytic oxidation of benzene and methyl tert-butyl ether

    SciTech Connect (OSTI)

    Dangi, S.; Abraham, M.A. [Univ. of Tulsa, OK (United States). Dept. of Chemical Engineering] [Univ. of Tulsa, OK (United States). Dept. of Chemical Engineering

    1997-06-01T23:59:59.000Z

    The performance of a catalytic incinerator depends on the nature of the compounds being oxidized and cannot be predicted simply by knowing the performance of the incinerator with pure-component model compounds. Considering the importance of mixture effects, an attempt was made to develop a combined model to predict the conversion when benzene and methyl tert-butyl ether (MTBE) are simultaneously oxidized. Complete catalytic oxidation of benzene and MTBE, singly and in mixtures, was investigated over a platinum catalyst. No inhibition effects were seen with benzene, but MTBE conversion was distinctly inhibited by benzene. A Mars-van Krevelen rate model was used to explain the results. Model parameters were obtained from pure-component experiments and then incorporated into a multicomponent model without any adjustment or additional rate parameters. The multicomponent model was able to predict the conversion of benzene and MTBE oxidation in the binary mixture using the pure-component data without adjustable parameters.

  15. Microbial degradation of alkylbenzenes under sulfate-reducing and methanogenic conditions. Final report, May 89-Apr 91

    SciTech Connect (OSTI)

    Beller, H.R.; Edwards, E.A.; Grbic-Galic, D.; Reinhard, M.

    1991-07-01T23:59:59.000Z

    Aquifer solids and soils obtained from various hydrocarbon-contaminated sites were used to investigate the ability of indigenous microorganisms to degrade monoaromatic hydrocarbons under strictly anaerobic conditions. In anaerobic microcosms inoculated with fuel-contaminated soil from the Patuxent River site, toluene degradation occurred concomitantly with sulfate reduction and ferric iron reduction. Similar results were obtained with suspended enrichments derived from the microcosms. Stoichiometric data and other observations suggested that sulfate reduction was closely linked to toluene degradation, whereas iron reduction was a secondary, potentially abiotic, reaction between ferric iron and biogenic hydrogen sulfide. The presence of millimolar concentrations of amorphous Fe(OH)3 in Patuxent River microcosms and enrichments either greatly facilitated the onset of toluene degradation or accelerated the rate once degradation had begun. Fermentative/methanogenic microcosms and enrichments that degraded toluene and o-xylene without added exogenous electron acceptors (except CO2) were developed from creosote-contaminated Pensacola samples. The microcosms initially underwent an acclimation lag of several months; however, once the degradation of aromatic hydrocarbons was initiated, it proceeded at a relatively rapid rate, and it was complete (resulting in mineralization to CO2 and CH4). Benzene, ethylbenzene, and p-xylene were not degraded.

  16. (CANCER RESEARCH 53. I02.VI026. March I. 1993] Benzene and Its Phenolic Metabolites Produce Oxidative DNA Damage in HL60

    E-Print Network [OSTI]

    California at Berkeley, University of

    (CANCER RESEARCH 53. I02.VI026. March I. 1993] Benzene and Its Phenolic Metabolites Produce ABSTRACT Benzene, an important industrial chemical, is myelotoxic and leuke- mogenic in humans effects. Here we report the induction of oxida- tive DNA damage by benzene and its phenolic metabolites

  17. Theoretical Investigation of Benzene Alkylation with Ethene over H-ZSM-5 Niels Hansen,*, Till Bruggemann, Alexis T. Bell,*, and Frerich J. Keil

    E-Print Network [OSTI]

    Bell, Alexis T.

    Theoretical Investigation of Benzene Alkylation with Ethene over H-ZSM-5 Niels Hansen,*, Till Bru Benzene alkylation with ethene over zeolite H-ZSM-5 has been investigated using density functional theory with the formation of a stable ethoxide intermediate which subsequently reacts with benzene to form the reaction

  18. Water on BN doped benzene: A hard test for exchange-correlation functionals and the impact of exact exchange on weak binding

    E-Print Network [OSTI]

    Alavi, Ali

    Water on BN doped benzene: A hard test for exchange-correlation functionals and the impact of exact on benzene, coronene, and graphene from quantum Monte Carlo calculations J. Chem. Phys. 134, 134701 (2011); 10.1063/1.3569134 The water-benzene interaction: Insight from electronic structure theories J. Chem

  19. Identification of Adsorbed Phenyl (C6H5) Groups on Metal Surfaces: Electron-Induced Dissociation of Benzene on Au(111)

    E-Print Network [OSTI]

    Ellison, Barney

    of Benzene on Au(111) Denis Syomin, Jooho Kim, and Bruce E. Koel* Department of Chemistry, Uni thermal and electron-induced chemistry of benzene (C6H6) adsorbed on a Au(111) surface. Thermal desorption of benzene occurs in three desorption peaks: monolayer at 239 K, bilayer at 155 K, and multilayer films

  20. Modeling the -lectrons of Benzene as Particles on a Ring Calculate the wavelength of the photon required for the first allowed (HOMO-LUMO) electronic

    E-Print Network [OSTI]

    Rioux, Frank

    Modeling the -lectrons of Benzene as Particles on a Ring Calculate the wavelength of the photon required for the first allowed (HOMO-LUMO) electronic transition involving the -electrons of benzene. Energy Level Diagram for Benzene's Electrons _______ _______4 h 2 2 m C 2 n = +/- 2 LUMO h 2 2 m C 2

  1. Charge transfer from TiO2 into adsorbed benzene diazonium compounds Tel-Aviv University, School of Electrical Engineering, Ramat-Aviv 69978, Israel

    E-Print Network [OSTI]

    Shapira, Yoram

    Charge transfer from TiO2 into adsorbed benzene diazonium compounds A. Merson Tel-Aviv University benzene diazonium compounds has been investigated using cyclic voltammetry, x-ray photoelectron that the potential of maximum electron transfer depends strongly on the dipole moment of the benzene compound. Two

  2. Spatial variation in ambient benzene concentrations over a city park1 Samantha Fridh, MSPH, and Amy L. Stuart, MS, PhD2

    E-Print Network [OSTI]

    Stuart, Amy L.

    1 Spatial variation in ambient benzene concentrations over a city park1 Samantha Fridh of South Florida3 4 Abstract5 Passive diffusive samplers were used to collect ambient benzene, passive sampling18 19 Introduction20 Benzene is a known human carcinogen (e.g. it is classified

  3. Supplement for "AMS and LC/MS analyses of SOA from the photooxidation of benzene and 1,3,5-trimethylbenzene in

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    1 Supplement for "AMS and LC/MS analyses of SOA from the photooxidation of benzene and 1@nies.go.jp) #12;2 Fig. S1: Time profiles (a) benzene concentration and HROrg and HRNO3 particulate product during the photooxidation of benzene (run 3). #12;3 Fig. S2. Yield curves for SOA formed from

  4. Hematotoxicity in Workers Exposed to Low Levels of Benzene Qing Lan1,*, Luoping Zhang2,*, Guilan Li3, Roel Vermeulen1, Rona S. Weinberg4, Mustafa

    E-Print Network [OSTI]

    California at Berkeley, University of

    Hematotoxicity in Workers Exposed to Low Levels of Benzene Qing Lan1,*, Luoping Zhang2,*, Guilan Li for Cancer Research, NCI, NIH, DHHS, Bethesda, MD 20892, USA. Abstract Benzene is known to have toxic effects million (ppm) remains uncertain. In a study of 250 workers exposed to benzene, white blood cell

  5. The Nature of the Intramolecular Charge Transfer Excited State in p-Pyrrolocyanobenzene (PBN) and Other Derivatives of Benzene Substituted by Electron Donor and Acceptor

    E-Print Network [OSTI]

    Haas, Yehuda

    -Pyrrolocyanobenzene (PBN) and Other Derivatives of Benzene Substituted by Electron Donor and Acceptor Groups Shmuel Zilberg analysis of these compounds, in which benzene is substituted by an electron withdrawing group of benzene and is of a covalent nature. Light emission from this state is due to local excitation

  6. Mesomorphic properties and molecular structure. II. Structure of the smectic A phase in the 4-propionyl-4' -n-alkanoyloxy-azo-benzene series

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    -propionyl-4' -n-alkanoyloxy-azo-benzene series G. Albertini (*), E. Fanelli (**), D. Guillon (***), S dilatométrie et par diffraction des rayons X. La comparaison avec les données de la série 4-acetyl-4'-n-alkanoyloxy-azo-benzene-alka- noyloxy-azo-benzene series have been obtained by using dilatometry and X-ray diffraction techniques

  7. Study of the Thermal Diffusion Behavior of Alkane/Benzene Mixtures by Thermal Diffusion Forced Rayleigh Scattering Experiments and Lattice Model Calculations

    E-Print Network [OSTI]

    Luettmer-Strathmann, Jutta

    Study of the Thermal Diffusion Behavior of Alkane/Benzene Mixtures by Thermal Diffusion Forced mixtures of linear alkanes (heptane, nonane, undecane, tridecane, pentadecane, heptadecane) in benzene has and temperatures. The Soret coefficient ST of the alkane was found to be negative for these n-alkane/benzene

  8. Structure of hydrophobic hydration of benzene and hexafluorobenzene from first principles

    SciTech Connect (OSTI)

    Allesch, M; Schwegler, E; Galli, G

    2006-10-23T23:59:59.000Z

    We report on the aqueous hydration of benzene and hexafluorobenzene, as obtained by carrying out extensive (>100 ps) first principles molecular dynamics simulations. Our results show that benzene and hexafluorobenzene do not behave as ordinary hydrophobic solutes, but rather present two distinct regions, one equatorial and the other axial, that exhibit different solvation properties. While in both cases the equatorial regions behave as typical hydrophobic solutes, the solvation properties of the axial regions depend strongly on the nature of the {pi}-water interaction. In particular, {pi}-hydrogen and {pi}-lone pair interactions are found to dominate in benzene and hexafluorobenzene, respectively, which leads to substantially different orientations of water near the two solutes. We present atomic and electronic structure results (in terms of Maximally Localized Wannier Functions) providing a microscopic description of benzene- and hexafluorobenzene-water interfaces, as well as a comparative study of the two solutes. Our results point at the importance of an accurate description of interfacial water in order to characterize hydration properties of apolar molecules, as these are strongly influenced by subtle charge rearrangements and dipole moment redistributions in interfacial regions.

  9. Process Biochemistry 36 (2001) 765772 Benzene degradation in a two-phase partitioning bioreactor by

    E-Print Network [OSTI]

    Daugulis, Andrew J.

    2001-01-01T23:59:59.000Z

    Process Biochemistry 36 (2001) 765­772 Benzene degradation in a two-phase partitioning bioreactor November 2000; accepted 22 November 2000 Abstract An aqueous-organic, two-phase bioreactor system was used into the aqueous phase of the two-phase partitioning bioreactor, which consisted of a 1 l aqueous phase and 500 ml

  10. Physiologically Based Pharmacokinetic (PBPK) Modeling of Benzene in Humans: A Bayesian Approach

    E-Print Network [OSTI]

    that are now often used in risk assessment to better extrapolate from experimental animals to humans and from hPhysiologically Based Pharmacokinetic (PBPK) Modeling of Benzene in Humans: A Bayesian Approach for variability among humans, the mathematical model must be integrated into a statistical framework

  11. Antiferromagnetic Exchange Interaction between Electrons on Degenerate LUMOs in Benzene Dianion

    E-Print Network [OSTI]

    Matsuura, Hiroyasu; Fukuyama, Hidetoshi

    2012-01-01T23:59:59.000Z

    We discuss the ground state of Benzene dianion (Bz$^{2-}$) on the basis of the numerical diagonalization method of an effective model of $\\pi$ orbitals. It is found that the ground state can be the spin singlet state, and the exchange coupling between LUMOs can be antiferromagnetic.

  12. Formation of the diphenyl molecule in the crossed beam reaction of phenyl radicals with benzene

    SciTech Connect (OSTI)

    Zhang Fangtong; Gu Xibin; Kaiser, Ralf I. [Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822 (United States)

    2008-02-28T23:59:59.000Z

    The chemical dynamics to form the D5-diphenyl molecule, C{sub 6}H{sub 5}C{sub 6}D{sub 5}, via the neutral-neutral reaction of phenyl radicals (C{sub 6}H{sub 5}) with D6-benzene (C{sub 6}D{sub 6}), was investigated in a crossed molecular beams experiment at a collision energy of 185 kJ mol{sup -1}. The laboratory angular distribution and time-of-flight spectra of the C{sub 6}H{sub 5}C{sub 6}D{sub 5} product were recorded at mass to charge m/z of 159. Forward-convolution fitting of our data reveals that the reaction dynamics are governed by an initial addition of the phenyl radical to the {pi} electron density of the D6-benzene molecule yielding a short-lived C{sub 6}H{sub 5}C{sub 6}D{sub 6} collision complex. The latter undergoes atomic deuterium elimination via a tight exit transition state located about 30 kJ mol{sup -1} above the separated reactants; the overall reaction to form D5-diphenyl from phenyl and D6-benzene was found to be weakly exoergic. The explicit identification of the D5-biphenyl molecules suggests that in high temperature combustion flames, a diphenyl molecule can be formed via a single collision event between a phenyl radical and a benzene molecule.

  13. Reactor simulation of benzene ethylation and ethane dehydrogenation catalyzed by ZSM-5: A multiscale approach

    E-Print Network [OSTI]

    Bell, Alexis

    Reactor simulation of benzene ethylation and ethane dehydrogenation catalyzed by ZSM-5 Dehydrogenation a b s t r a c t Rate expressions are vital for analysis, design and operation of chemical reactors used the extended continuum model in the design equation of a fixed bed reactor and simulated

  14. Comparative Investigation of Benzene Steam Reforming over Spinel Supported Rh and Ir Catalysts

    SciTech Connect (OSTI)

    Mei, Donghai; Lebarbier, Vanessa MC; Rousseau, Roger J.; Glezakou, Vassiliki Alexandra; Albrecht, Karl O.; Kovarik, Libor; Flake, Matthew D.; Dagle, Robert A.

    2013-06-01T23:59:59.000Z

    In a combined experimental and first-principles density functional theory (DFT) study, benzene steam reforming (BSR) over MgAl2O4 supported Rh and Ir catalysts was investigated. Experimentally, it has been found that both highly dispersed Rh and Ir clusters (1-2 nm) on the MgAl2O4 spinel support are stable during the BSR in the temperature range of 700-850?C. Compared to the Ir/MgAl2O4 catalyst, the Rh/MgAl2O4 catalyst is more active with higher benzene turnover frequency and conversion. At typical steam conditions with the steam-to-carbon ratio > 12, the benzene conversion is only a weak function of the H2O concentration in the feed. This suggests that the initial benzene decomposition step rather than the benzene adsorption is most likely the rate-determined step in BSR over supported Rh and Ir catalysts. In order to understand the differences between the two catalysts, we followed with a comparative DFT study of initial benzene decomposition pathways over two representative model systems for each supported metal (Rh and Ir) catalysts. A periodic terrace (111) surface and an amorphous 50-atom metal cluster with a diameter of 1.0 nm were used to represent the two supported model catalysts under low and high dispersion conditions. Our DFT results show that the decreasing catalyst particle size enhances the benzene decomposition on supported Rh catalysts by lowering both C-C and C-H bond scission. The activation barriers of the C-C and the C-H bond scission decrease from 1.60 and 1.61 eV on the Rh(111) surface to 1.34 and 1.26 eV on the Rh50 cluster. For supported Ir catalysts, the decreasing particle size only affects the C-C scission. The activation barrier of the C-C scission of benzene decreases from 1.60 eV on the Ir(111) surface to 1.35 eV on the Ir50 cluster while the barriers of the C-H scission are practically the same. The experimentally measured higher BSR activity on the supported highly dispersed Rh catalyst can be rationalized by the thermodynamic limitation for the very first C-C bond scission of benzene on the small Ir50 catalyst. The C-C bond scission of benzene on the small Ir50 catalyst is highly endothermic although the barrier is competitive with the barriers of both the C-C and the C-H bond-breakings on the small Rh50 catalyst. The calculations also imply that, for the supported Rh catalysts the C-C and C-H bond scissions are competitive, independently of the Rh cluster sizes. After the initial dissociation step via either the C-C or the C-H bond scission, the C-H bond breaking seems to be more favorable rather than the C-C bond breaking on the larger Rh terrace surface. This work was financially supported by the United States Department of Energy’s Office of Biomass Program’s. Computing time was granted by a user project at the Molecular Science Computing Facility in the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory.

  15. On the role of delocalization in benzene: Theoretical and experimental investigation of the effects of strained ring fusion

    SciTech Connect (OSTI)

    Faust, R. [Lawrence Berkeley Lab., CA (United States). Chemical Sciences Div.; [California Univ., Berkeley, CA (United States). Dept. of Chemistry

    1993-04-01T23:59:59.000Z

    When an important compound`s discovery dates back as far as 1825, one would imagine that every facet of its chemical and physical properties has been illuminated in the meantime. Benzene, however, has not ceased to challenge the chemist`s notion of structure and bonding since its first isolation by Michael Faraday. This report is divided into the following six chapters: 1. Aromaticity -- Criteria, manifestations, structural limitations; 2. The role of delocalization in benzene; 3. The thermochemical properties of benzocyclobutadienologs; 4. Ab initio study of benzenes fused to four-membered rings; 5. Non-planar polycyclic aromatic hydrocarbons; and 6. Experimental details and input decks. 210 Refs.

  16. Mechanism reduction for multicomponent surrogates: A case study using toluene reference fuels

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Niemeyer, Kyle E.; Sung, Chih-Jen

    2014-11-01T23:59:59.000Z

    Strategies and recommendations for performing skeletal reductions of multicomponent surrogate fuels are presented, through the generation and validation of skeletal mechanisms for a three-component toluene reference fuel. Using the directed relation graph with error propagation and sensitivity analysis method followed by a further unimportant reaction elimination stage, skeletal mechanisms valid over comprehensive and high-temperature ranges of conditions were developed at varying levels of detail. These skeletal mechanisms were generated based on autoignition simulations, and validation using ignition delay predictions showed good agreement with the detailed mechanism in the target range of conditions. When validated using phenomena other than autoignition, such as perfectly stirred reactor and laminar flame propagation, tight error control or more restrictions on the reduction during the sensitivity analysis stage were needed to ensure good agreement. In addition, tight error limits were needed for close prediction of ignition delay when varying the mixture composition away from that used for the reduction. In homogeneous compression-ignition engine simulations, the skeletal mechanisms closely matched the point of ignition and accurately predicted species profiles for lean to stoichiometric conditions. Furthermore, the efficacy of generating a multicomponent skeletal mechanism was compared to combining skeletal mechanisms produced separately for neat fuel components; using the same error limits, the latter resulted in a larger skeletal mechanism size that also lacked important cross reactions between fuel components. Based on the present results, general guidelines for reducing detailed mechanisms for multicomponent fuels are discussed.

  17. Mechanism reduction for multicomponent surrogates: A case study using toluene reference fuels

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Niemeyer, Kyle E.; Sung, Chih-Jen

    2014-11-01T23:59:59.000Z

    Strategies and recommendations for performing skeletal reductions of multicomponent surrogate fuels are presented, through the generation and validation of skeletal mechanisms for a three-component toluene reference fuel. Using the directed relation graph with error propagation and sensitivity analysis method followed by a further unimportant reaction elimination stage, skeletal mechanisms valid over comprehensive and high-temperature ranges of conditions were developed at varying levels of detail. These skeletal mechanisms were generated based on autoignition simulations, and validation using ignition delay predictions showed good agreement with the detailed mechanism in the target range of conditions. When validated using phenomena other than autoignition, suchmore »as perfectly stirred reactor and laminar flame propagation, tight error control or more restrictions on the reduction during the sensitivity analysis stage were needed to ensure good agreement. In addition, tight error limits were needed for close prediction of ignition delay when varying the mixture composition away from that used for the reduction. In homogeneous compression-ignition engine simulations, the skeletal mechanisms closely matched the point of ignition and accurately predicted species profiles for lean to stoichiometric conditions. Furthermore, the efficacy of generating a multicomponent skeletal mechanism was compared to combining skeletal mechanisms produced separately for neat fuel components; using the same error limits, the latter resulted in a larger skeletal mechanism size that also lacked important cross reactions between fuel components. Based on the present results, general guidelines for reducing detailed mechanisms for multicomponent fuels are discussed.« less

  18. Modeling Studies on the Transport of Benzene and H2S in CO2-Water Systems

    SciTech Connect (OSTI)

    Zheng, L.; Spycher, N.; Xu, T.; Apps, J.; Kharaka, Y.; Birkholzer, J.T.

    2010-11-05T23:59:59.000Z

    In this study, reactive transport simulations were used to assess the mobilization and transport of organics with supercritical CO{sub 2} (SCC), and the co-injection and transport of H{sub 2}S with SCC. These processes were evaluated at conditions of typical storage reservoirs, and for cases of hypothetical leakage from a reservoir to an overlying shallower fresh water aquifer. Modeling capabilities were developed to allow the simulation of multiphase flow and transport of H{sub 2}O, CO{sub 2}, H{sub 2}S, as well as specific organic compounds (benzene), coupled with multicomponent geochemical reaction and transport. This included the development of a new simulator, TMVOC-REACT, starting from existing modules of the TOUGH2 family of codes. This work also included an extensive literature review, calculation, and testing of phase-partitioning properties for mixtures of the phases considered. The reactive transport simulations presented in this report are primarily intended to illustrate the capabilities of the new simulator. They are also intended to help evaluate and understand various processes at play, in a more qualitative than quantitative manner, and only for hypothetical scenarios. Therefore, model results are not intended as realistic assessments of groundwater quality changes for specific locations, and they certainly do not provide an exhaustive evaluation of all possible site conditions, especially given the large variability and uncertainty in hydrogeologic and geochemical parameter input into simulations. The first step in evaluating the potential mobilization and transport of organics was the identification of compounds likely to be present in deep storage formations, and likely to negatively impact freshwater aquifers if mobilized by SCC. On the basis of a literature review related to the occurrence of these organic compounds, their solubility in water and SCC, and their toxicity (as reflected by their maximum contaminant levels MCL), benzene was selected as a key compound for inclusion into numerical simulations. Note that considering additional organic compounds and/or mixtures of such compounds in the simulations was beyond the scope of this study, because of the effort required to research, calculate, and validate the phase-partitioning data necessary for simulations. The injection of CO{sub 2} into a deep saline aquifer was simulated, followed by modeling the leaching of benzene by SCC and transport of benzene to an overlying aquifer along a hypothetical leakage pathway. One- and two-dimensional models were set up for this purpose. The target storage formation was assumed to initially contain about 10{sup -4} ppm benzene. Model results indicate that: (1) SCC efficiently extracts benzene from the storage formation. (2) Assuming equilibrium, the content of benzene in SCC is roportional to the concentration of benzene in the aqueous and solid phases. (3) Benzene may co-migrate with CO{sub 2} into overlying aquifers if a leakage pathway is present. Because the aqueous solubility of benzene in contact with CO{sub 2} is lower than the aqueous solubility of CO{sub 2}, benzene is actually enriched in the CO{sub 2} phase as the plume advances. (4) For the case studied here, the resulting aqueous benzene concentration in the overlying aquifer is on the same order of magnitude as the initial concentration in the storage formation. This generic modeling study illustrates, in a semi-quantitative manner, the possible mobilization of benzene by SCC. The extent to which the mobilization of this organic compound evolves temporally and spatially depends on a large number of controlling parameters and is largely site specific. Therefore, for more 'truly' predictive work, further sensitivity studies should be conducted, and further modeling should be integrated with site-specific laboratory and/or field experimental data. The co-injection of H{sub 2}S with CO{sub 2} into a deep saline aquifer was also simulated. In addition, the model considered leakage of the supercritical CO{sub 2}+H{sub 2}S mixture along a preferential p

  19. Interaction energies of monosubstituted benzene dimers via nonlocal density functional theory

    E-Print Network [OSTI]

    T. Thonhauser; Aaron Puzder; David C. Langreth

    2005-09-15T23:59:59.000Z

    We present density-functional calculations for the interaction energy of monosubstituted benzene dimers. Our approach utilizes a recently developed fully nonlocal correlation energy functional, which has been applied to the pure benzene dimer and several other systems with promising results. The interaction energy as a function of monomer distance was calculated for four different substituents in a sandwich and two T-shaped configurations. In addition, we considered two methods for dealing with exchange, namely using the revPBE generalized gradient functional as well as full Hartree-Fock. Our results are compared with other methods, such as Moller-Plesset and coupled-cluster calculations, thereby establishing the usefulness of our approach. Since our density-functional based method is considerably faster than other standard methods, it provides a computational inexpensive alternative, which is of particular interest for larger systems where standard calculations are too expensive or infeasible.

  20. Correlating benzene, total hydrocarbon and carbon monoxide emissions from wood-fired boilers

    SciTech Connect (OSTI)

    Hubbard, A.J.; Grande, D.E.; Berens, J.R. [Wisconsin Dept. of Natural Resources, Madison, WI (United States); Piotrowski, J. [Tenneco Packaging, Inc., Tomahawk, WI (United States)

    1997-12-31T23:59:59.000Z

    Hazardous air pollutants, including benzene, are generated by the incomplete combustion of fuels. Organic compound emissions, which are generally products of incomplete combustion, are reduced by promoting high quality combustion, for example by controlling furnace exit temperatures and establishing minimum residence times. Monitoring carbon monoxide (CO) emissions is important since the amount of carbon monoxide emitted represents the quality of combustion which in turn represents the amount of hazardous air pollutants being generated. Total hydrocarbon (THC) emissions are also related to the quality of combustion. Recently the Wisconsin Department of Natural Resources (DNR) measured the benzene and total hydrocarbon emissions from two large industrial wood fired boilers. These boilers are located at Tenneco Packaging, a container board manufacturing facility in northern Wisconsin. Temperature, oxygen and carbon monoxide concentrations were sampled continuously by Tenneco Packaging`s emission monitoring system. The Department`s team used an organic vapor analyzer to continuously measure concentrations of total hydrocarbons (THC). The Department`s team also used a modified USEPA Method 18 sampling train to capture organic vapors for subsequent analysis by gas chromatography. The data show correlations between benzene and carbon monoxide, and between benzene and THC concentrations. The emissions sampling occurred both upstream of the particulate emissions control system as well as at the stack. The CO variations during actual boiler operation appeared to be well correlated with changes in boiler steam load. That is, increases in CO generally accompanied a change, either up or down, in boiler load. Lower concentrations of CO were associated with stable combustion, as indicated by periods of constant or nearly constant boiler load.

  1. Ab initio study of the kinetics of hydrogen abstraction reactions on toluene and tetralin

    SciTech Connect (OSTI)

    Beste, Ariana [ORNL; Britt, Phillip F [ORNL; Buchanan III, A C [ORNL; Harrison, Robert J [ORNL; Hathorn, Bryan C [ORNL

    2008-01-01T23:59:59.000Z

    Hydrogen abstraction reactions play a key role in many thermal and catalytic processes involved in the production of fuels and chemicals. In this paper, the reaction barriers and rate constants for the hydrogen abstraction reactions on toluene and tetralin by the benzyl radical are calculated by ab initio methods. These reactions are representatives of similar reactions occurring in the thermolysis of lignin model compounds containing the phenethyl phenyl ether (PPE) structural moiety. Thermolysis of PPE occurs by a free radical chain mechanism in which the product selectivity arises from competitive hydrogen abstraction at the benzylic and nonbenzylic methylen sites by chain carrying benzyl and phenoxyl radicals. The title reactions serve to calibrate the theoretical methods to be used in the study of PPE through comparison of the rate constants and the reaction enthalpies with reliable experimental values. In this study, we used two different hybrid density functionals (BHandHLYP, B3LYP) and second-order perturbation theory to obtain equilibrium and transition state geometries. Multiple transition states were found for both reactions. BHandHLYP underestimates and second-order perturbation theory overestimates the reaction barriers; B3LYP energy barriers agree well with experiment. Absolute and relative rate constants were calculated using transition state theory. We found that the relative rate constant using the B3LYP functional agrees within a factor of 2.0 with experiment at the experimental temperature of 333 K, indicating that the B3LYP functional will be successful in predicting relative rate constants for hydrogen abstraction reactions participating in the pyrolysis of PPE.

  2. Determination of phase equilibria for the binary systems polystyrene/cyclohexane and polystyrene/toluene and for the ternary system polystyrene/cyclohexane/toluene at 423 K, 433 K, and 448 K using perturbation gas chromatography / cby Kathryn Rion Hanneman

    E-Print Network [OSTI]

    Hanneman, Kathryn Rion

    1984-01-01T23:59:59.000Z

    -of-state model, and the lattice-fluid model of Sanchez and Lacombe. The vapor-liquid equilibrium data were found to be insensitive to the cyclohexane/toluene fit parameter in the Flory's equation-of-state model, the Flory-Huggins (volume and segment fraction...) model and the Sanchez and Lacombe model. However, the vapor-liquid equilibrium data's sensitivity to the CH/T parameter in Bonner and Brockmeier's simplified Flory's model was not determined. At the temperatures and solvent partial pressures studied...

  3. Benzene under High Pressure: a Story of Molecular Crystals Transforming to Saturated Networks, with a Possible Intermediate Metallic Phase

    SciTech Connect (OSTI)

    Wen, Xiao-Dong [Cornell Univ., Ithaca, NY (United States). Lab. of Atomic and Solid State Physics (LASSP) and Cornell Center for Materials Research (CCMR); Hoffmann, Roald [Cornell Univ., Ithaca, NY (United States). Lab. of Atomic and Solid State Physics (LASSP) and Cornell Center for Materials Research (CCMR); Ashcroft, N. W. [Cornell Univ., Ithaca, NY (United States). Lab. of Atomic and Solid State Physics (LASSP) and Cornell Center for Materials Research (CCMR)

    2011-06-15T23:59:59.000Z

    In a theoretical study, benzene is compressed up to 300 GPa. The transformations found between molecular phases generally match the experimental findings in the moderate pressure regime (<20 GPa): phase I (Pbca) is found to be stable up to 4 GPa, while phase II (P43212) is preferred in a narrow pressure range of 4–7 GPa. Phase III (P21/c) is at lowest enthalpy at higher pressures. Above 50 GPa, phase V (P21 at 0 GPa; P21/c at high pressure) comes into play, slightly more stable than phase III in the range of 50–80 GP, but unstable to rearrangement to a saturated, four-coordinate (at C), one-dimensional polymer. Actually, throughout the entire pressure range, crystals of graphane possess lower enthalpy than molecular benzene structures; a simple thermochemical argument is given for why this is so. In several of the benzene phases there nevertheless are substantial barriers to rearranging the molecules to a saturated polymer, especially at low temperatures. Even at room temperature these barriers should allow one to study the effect of pressure on the metastable molecular phases. Molecular phase III (P21/c) is one such; it remains metastable to higher pressures up to ?200 GPa, at which point it too rearranges spontaneously to a saturated, tetracoordinate CH polymer. At 300 K the isomerization transition occurs at a lower pressure. Nevertheless, there may be a narrow region of pressure, between P = 180 and 200 GPa, where one could find a metallic, molecular benzene state. We explore several lower dimensional models for such a metallic benzene. We also probe the possible first steps in a localized, nucleated benzene polymerization by studying the dimerization of benzene molecules. Several new (C6H6)2 dimers are predicted.

  4. Adsorption of Benzene on a Mo(112)-c(2 2)-[SiO4] Surface M. S. Chen, A. K. Santra, and D. W. Goodman*

    E-Print Network [OSTI]

    Goodman, Wayne

    Adsorption of Benzene on a Mo(112)-c(2 × 2)-[SiO4] Surface M. S. Chen, A. K. Santra, and D. W-3012 ReceiVed: May 21, 2004; In Final Form: August 13, 2004 The orientation and growth of benzene). Benzene on the c(2 × 2)-[SiO4] surface is bound with its molecular plane parallel to the surface plane

  5. DownloadedBy:[CanadianResearchKnowledgeNetwork]At:16:1617June2008 Journal of Toxicology and Environmental Health, Part A, 71: 11001108, 2008

    E-Print Network [OSTI]

    Bortolotti, Gary R.

    exposed to the rodent LOAEL for combined benzene and toluene. This study indicates that American kestrels of Benzene and Toluene on Vitamin A Status and Humoral and Cell-Mediated Immunity in Wild and Captive American Kestrels Toxicity of benzene and toluene in kestrels Mandy L. Olsgard1 , Gary R. Bortolotti3

  6. The benzene metabolite trans,trans-muconaldehyde blocks gap junction intercellular communication by cross-linking connexin43

    SciTech Connect (OSTI)

    Rivedal, Edgar [Department of Cancer Prevention, Institute for Cancer Research, Norwegian Radium Hospital, Montebello, N-0310 Oslo (Norway)], E-mail: edgarr@rr-research.no; Leithe, Edward [Department of Cancer Prevention, Institute for Cancer Research, Norwegian Radium Hospital, Montebello, N-0310 Oslo (Norway)

    2008-11-01T23:59:59.000Z

    Benzene is used at large volumes in many different human activities. Hematotoxicity and cancer-causation as a result of benzene exposure was recognized many years ago, but the mechanisms involved remain unclear. Aberrant regulation of gap junction intercellular communication (GJIC) has been linked to both cancer induction and interference with normal hematopoietic development. We have previously suggested that inhibition of GJIC may play a role in benzene toxicity since benzene metabolites were found to block GJIC, the ring-opened trans,trans-muconaldehyde (MUC) being the most potent metabolite. In the present work we have studied the molecular mechanisms underlying the MUC-induced inhibition of gap junctional communication. We show that MUC induces cross-linking of the gap junction protein connexin43 and that this is likely to be responsible for the induced inhibition of GJIC, as well as the loss of connexin43 observed in Western blots. We also show that glutaraldehyde possesses similar effects as MUC, and we compare the effects to that of formaldehyde. The fact that glutaraldehyde and formaldehyde have been associated with induction of leukemia as well as disturbance of hematopoiesis, strengthens the possible link between the effect of MUC on gap junctions, and the toxic effects of benzene.

  7. Aggregation of hexylammonium propionate in DMSO-benzene and DMSO-D?O solvent systems

    E-Print Network [OSTI]

    Constein, Vernon George

    1974-01-01T23:59:59.000Z

    Fig. 18. Aggregation number plots for HAP in 75@a DpO/25$ DMSO-de ~ 72 3. 0 CHg (CH p ) 4CH pNH 3 2. 00 1. 00 ~ 0. 00 I A U 0 i 3. 00 + CHp (CHg) 4CHpNH3 0 0 2. 00 1. 00 0. 0 1. 00 1. 20 1. 40 1. 60 1. 80 2. 00 2 + log tS] 73 Fig... The relationships between a micelle forming surfactant, hexylammonium propionate (1), and the overlapping mixed solvent systems of benzene/dimethyl- sulfoxide/water have been investigated using 'H nuclear magnetic resonance techniques. The changes in t' he...

  8. Approved for public release; distribution is unlimited. ERDC/TN APCRP-CC-15

    E-Print Network [OSTI]

    US Army Corps of Engineers

    ) and will provide an alternative to acrolein (2-propenal) and xylene (1,2-, 1,3-, and 1,4-dimethyl benzene), which

  9. JV Task 86 - Identifying the Source of Benzene in Indoor Air Using Different Compound Classes from TO-15 Data

    SciTech Connect (OSTI)

    Steven B. Hawthorne

    2007-04-15T23:59:59.000Z

    Volatile organic compound (VOC) data that had already been collected using EPA method TO-15 at four different sites under regulatory scrutiny (a school, strip mall, apartment complex, and business/residential neighborhood) were evaluated to determine whether the source of indoor air benzene was outdoor air or vapor intrusion from contaminated soil. Both the use of tracer organics characteristic of different sources and principal component statistical analysis demonstrated that the source of indoor air at virtually all indoor sampling locations was a result of outdoor air, and not contaminated soil in and near the indoor air-sampling locations. These results show that proposed remediation activities to remove benzene-contaminated soil are highly unlikely to reduce indoor air benzene concentrations. A manuscript describing these results is presently being prepared for submission to a peer-reviewed journal.

  10. Exposure to methyl tert-butyl ether, benzene, and total hydrocarbons at the Singapore-Malaysia causeway immigration checkpoint

    SciTech Connect (OSTI)

    Tan, C.; Ong, H.Y.; Kok, P.W. [and others

    1996-12-31T23:59:59.000Z

    The primary aim of this study was to determine the extent and levels of exposure to volatile organic compounds (VOCs) from automobile emissions in a group of immigration officers at a busy cross-border checkpoint. A majority (80%) of the workers monitored were exposed to benzene at levels between 0.01 and 0.5 ppm, with only 1.2% exceeding the current Occupational Safety and Health Administration occupational exposure limit of 1 ppm. The geometric mean (GM) concentrations of 8-hr time-weighted average exposure were 0.03 ppm, 0.9 ppm, and 2.46 ppm for methyl-tert-butyl ether (MTBE), benzene, and total hydrocarbons (THC), respectively. The highest time-weighted average concentrations measured were 1.05 ppm for MTBE, 2.01 ppm for benzene, and 34 ppm for THC. It was found that motorbikes emitted a more significant amount of pollutants compared with motor cars. On average, officers at the motorcycle booths were exposed to four to five times higher levels of VOCs (GMs of 0.07 ppm, 0.23 ppm, and 4.7 ppm for MTBE, benzene, and THC) than their counterparts at the motor car booths (GMs of 0.01 ppm, 0.05 ppm, and 1.5 ppm). The airborne concentrations of all three pollutants correlated with the flow of vehicle traffic. Close correlations were also noted for the concentrations in ambient air for the three pollutants measured. Benzene and MTBE had a correlation coefficient of 0.97. The overall findings showed that the concentrations of various VOCs were closely related to the traffic density, suggesting that they were from a common source, such as exhaust emissions from the vehicles. The results also indicated that although benzene, MTBE, and THC are known to be volatile, a significant amount could still be detected in the ambient environment, thus contributing to our exposure to these compounds. 4 refs., 6 figs.

  11. Evolution of soot size distribution in premixed ethylene/air and ethylene/benzene/air flames: Experimental and modeling study

    SciTech Connect (OSTI)

    Echavarria, Carlos A.; Sarofim, Adel F.; Lighty, JoAnn S. [Department of Chemical Engineering, University of Utah, Salt Lake City, UT (United States); D'Anna, Andrea [Dipartimento di Ingegneria Chimica, Universita ''Federico II'' di Napoli, Naples (Italy)

    2011-01-15T23:59:59.000Z

    The effect of benzene concentration in the initial fuel on the evolution of soot size distribution in ethylene/air and ethylene/benzene/air flat flames was characterized by experimental measurements and model predictions of size and number concentration within the flames. Experimentally, a scanning mobility particle sizer was used to allow spatially resolved and online measurements of particle concentration and sizes in the nanometer-size range. The model couples a detailed kinetic scheme with a discrete-sectional approach to follow the transition from gas-phase to nascent particles and their coagulation to larger soot particles. The evolution of soot size distribution (experimental and modeled) in pure ethylene and ethylene flames doped with benzene showed a typical nucleation-sized (since particles do not actually nucleate in the classical sense particle inception is often used in place of nucleation) mode close to the burner surface, and a bimodal behavior at greater height above burner (HAB). However, major features were distinguished between the data sets. The growth of nucleation and agglomeration-sized particles was faster for ethylene/benzene/air flames, evidenced by the earlier presence of bimodality in these flames. The most significant changes in size distribution were attributed to an increase in benzene concentration in the initial fuel. However, these changes were more evident for high temperature flames. In agreement with the experimental data, the model also predicted the decrease of nucleation-sized particles in the postflame region for ethylene flames doped with benzene. This behavior was associated with the decrease of soot precursors after the main oxidation zone of the flames. (author)

  12. Multiple activation pathways of benzene leading to products with varying genotoxic characteristics

    SciTech Connect (OSTI)

    Glatt, H.; Ludewig, G.; Platt, K.L.; Klein, J.; Oesch, F. (Univ. of Mainz (West Germany)); Padykula, R.; Berchtold, G.A. (Massachusetts Institute of Technology, Cambridge (USA))

    1989-07-01T23:59:59.000Z

    Benzene and 13 potential metabolites were investigated for genotoxicity in Salmonella typhimurium and V79 Chinese hamster cells. In the presence of NADPH-fortified hepatic postmitochondrial fraction (S9 mix), benzene reverted his S. typhimurium strains. The effect was strongest in strain TA1535. Among the potential metabolites, only the trans-1,2-dihydrodiol, in the presence of S9 mix, and the diol epoxides, in the presence and absence of S9 mix, proved mutagenic in this strain. The anti-diol epoxide was more potent than the syndiastereomer. Both enantiomers of the anti-diastereomer showed similar activities. S9 mix did not appreciably affect the mutagenicity of the anti-diol epoxide. However, detoxification was observed when purified rat liver dihydrodiol dehydrogenase was used at concentrations comparable to that present in the liver. Elevated frequencies of micronucleated cells were observed after treatment with hydroquinone, 1,2,4-trihydroxybenzene, catechol, phenol, 1,2,3-trihydroxybenzene, and quinone. By far the most prominent effect in the whole study was the potent induction of gene mutations by quinone and hydroquinone. This unique and narrow spectrum of genotoxic activities differs from the broad spectrum observed with the antidiol epoxide, suggesting qualitative differences in their interaction with genetic material.

  13. CH-{\\pi} interaction-induced deep orbital deformation in a benzene-methane weak binding system

    E-Print Network [OSTI]

    Li, Jianfu

    2015-01-01T23:59:59.000Z

    The nonbonding interaction between benzene and methane, called CH-{\\pi} interaction, plays an important role in physical, chemical, and biological fields. CH-{\\pi} interaction can decrease the system total energy and promote the formation of special geometric configurations. This work investigates systemically the orbital distribution and composition of the benzene-methane complex for the first time using ab initio calculation based on different methods and basis sets. Surprisingly, we find strong deformation in HOMO-4 and LUMO+2 induced by CH-{\\pi} interaction, extending the general view that nonbonding interaction does not cause orbital change of molecules.

  14. Phase Behaviour of Carbon Dioxide + Benzene + Water Ternary Mixtures at High Pressures and Temperatures up to 300 MPa and 600 K

    E-Print Network [OSTI]

    1 Phase Behaviour of Carbon Dioxide + Benzene + Water Ternary Mixtures at High Pressures for the phase coexistence of carbon dioxide + benzene + water ternary mixtures. Phase coexistence was observed exceptions are the systematic studies6-9 of ternary mixtures containing carbon dioxide with large alkanes

  15. Adsorption, Desorption, and Dissociation of Benzene on TiO2(110) and Pd/TiO2(110)

    SciTech Connect (OSTI)

    Zhou, Jing [ORNL; Dag, Sefa [ORNL; Senanayake, Sanjaya D [ORNL; Hathorn, Bryan C [ORNL; Kalinin, Sergei V [ORNL; Meunier, Vincent [ORNL; Mullins, David R [ORNL; Overbury, Steven {Steve} H [ORNL; Baddorf, Arthur P [ORNL

    2006-01-01T23:59:59.000Z

    Adsorption and reaction of benzene molecules on clean TiO{sub 2}(110) and on TiO{sub 2}(110) with deposited Pd nanoparticles are investigated using a combination of scanning tunneling microscopy (STM), temperature-programmed desorption, and first-principles calculations. Above {approx}50 K, the one-dimensional motion of benzene between bridging oxygen rows is shown to be too fast for STM imaging. At 40 K benzene molecules form chains on top of titanium rows, with calculations indicating every other benzene is rotated 30{sup o}. Both experimental and theoretical studies find no dissociative reactivity of benzene on the clean TiO{sub 2}(110) surface, due to little hybridization between TiO{sub 2} and benzene electronic states. After deposition of Pd nanoparticles, molecular benzene is observed with STM both on the substrate and adjacent to metallic particles. Upon heating to 800 K, benzene fully breaks down into its atomic constituents in a multistep decomposition process.

  16. Reaction network and kinetics for the catalytic oxidation of toluene over V sub 2 O sub 5

    SciTech Connect (OSTI)

    Zhu, J.; Andersson, L.T. (Univ. of Lund (Sweden))

    1990-11-01T23:59:59.000Z

    The oxidation of three methyl-diphenylmethane isomers and of bibenzyl, benzyl alcohol, and benzaldehyde, which are intermediates in the catalytic oxidation of toluene over V{sub 2}O{sub 5}, has been studied to elucidate the reaction network and relative importance of various reactions. Selectivity dependences reveal that the network is composed mainly of three parallel reaction routes: (1) side-chain oxidation with consecutive reactions, (2) oxidative coupling with both parallel and consecutive reactions, and (3) carbon oxide formation. Coupling products are not negligible, with an initial selectivity of 29% (400{degree}C). Anthraquinone is produced mainly from o-methyl-diphenylmethane conditions and catalyst used. Selectivity dependences suggested product lumping and a simplified network. Kinetic analysis of this reaction network indicates that higher temperatures favor route 2 over route 1. The same initial intermediates for route 1 of side-chain oxidation and for route 2 of oxidative coupling are suggested.

  17. Theoretical Insight into the Interactions of TMA-Benzene and TMA-Pyrrole with B3LYP Density-Functional Theory (DFT) and ab Initio Second Order Mller-Plesset Perturbation

    E-Print Network [OSTI]

    Sussman, Joel L.

    Theoretical Insight into the Interactions of TMA-Benzene and TMA-Pyrrole with B3LYP Density theoretical investigation of the tetramethylammonium(TMA)-benzene and TMA-pyrrole complexes has been performed density in the 5 6 aromatic system of pyrrole is larger than that in the 6 6 system of benzene

  18. Comparing the effects of various fuel alcohols on the natural attenuation of Benzene Plumes using a general substrate interaction model

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    and Environmental Engineering, Rice University, MS-317, 6100 Main St., Houston, TX 77005, USA a r t i c l e i n f o a b s t r a c t Article history: Received 30 October 2009 Received in revised form 26 January 2010 generalizations about the level of impact of specific fuel alcohols on benzene plume dynamics. © 2010 Elsevier B

  19. Diffusion and Catalytic Cracking of 1,3,5 Tri-iso-propyl-benzene in FCC Catalysts

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    1 Diffusion and Catalytic Cracking of 1,3,5 Tri-iso- propyl-benzene in FCC Catalysts S.Al-Khattaf1 describes catalytic cracking experiments developed in a novel CREC Riser Simulator using 1,3,5-Tri-iso

  20. Some new progress on the light absorption properties of linear alkyl benzene solvent

    E-Print Network [OSTI]

    Yu, Guang-You; Huang, Ai-Zhong; Yu, Lei; Loh, Chang-Wei; Wang, Wen-Wen; Qian, Zhi-Qiang; Yang, Hai-Bo; Huang, Huang; Xu, Zong-Qiang; Zhu, Xue-Yuan; Xu, Bin; Qi, Ming

    2015-01-01T23:59:59.000Z

    Linear alkyl benzene (LAB) will be used as the solvent of a liquid scintillator mixture for the JUNO antineutrino experiment in the near future. Its light absorption property should therefore be understood prior to its effective use in the experiment. Attenuation length measurements at a light wavelength of 430 nm have been performed on samples of LAB prepared for the purpose of the JUNO experiment. Inorganic impurities in LAB have also been studied for their possibilities of light absorption in our wavelength of interest. In view of a tentative plan by the JUNO collaboration to utilize neutron capture with hydrogen in the detector, we have also presented in this work, a study on the carbon-hydrogen ratio and the relationship thereof with the attenuation length of the samples.

  1. Some new progress on the light absorption properties of linear alkyl benzene solvent

    E-Print Network [OSTI]

    Guang-You Yu; De-Wen Cao; Ai-Zhong Huang; Lei Yu; Chang-Wei Loh; Wen-Wen Wang; Zhi-Qiang Qian; Hai-Bo Yang; Huang Huang; Zong-Qiang Xu; Xue-Yuan Zhu; Bin Xu; Ming Qi

    2015-04-22T23:59:59.000Z

    Linear alkyl benzene (LAB) will be used as the solvent of a liquid scintillator mixture for the JUNO antineutrino experiment in the near future. Its light absorption property should therefore be understood prior to its effective use in the experiment. Attenuation length measurements at a light wavelength of 430 nm have been performed on samples of LAB prepared for the purpose of the JUNO experiment. Inorganic impurities in LAB have also been studied for their possibilities of light absorption in our wavelength of interest. In view of a tentative plan by the JUNO collaboration to utilize neutron capture with hydrogen in the detector, we have also presented in this work, a study on the carbon-hydrogen ratio and the relationship thereof with the attenuation length of the samples.

  2. Thermodynamic Features of Benzene-1,2-Diphosphonic Acid Complexes with Several Metal Ions

    SciTech Connect (OSTI)

    Syouhei Nishihama; Ryan P. Witty; Leigh R Martin; Kenneth L. Nash

    2013-08-01T23:59:59.000Z

    Among his many contributions to the advancement of f-element chemistry and separation science, Professor Gregory R. Choppin’s research group completed numerous investigations featuring the application of distribution techniques to the determination of metal complexation equilibrium quotients. Most of these studies focused on the chemistry of lanthanide and actinide complexes. In keeping with that tradition, this report discusses the complex formation equilibrium constants for complexes of trivalent europium (Eu3+) with benzene-1,2-diphosphonic acid (H4BzDP) determined using solvent extraction distribution experiments in 0.2 M (Na,H)ClO4 media in the temperature range of 5 – 45 degrees C. Protonation constants for HnBzDP4-n and stoichiometry and stability of BzDP4- complexes with Zn2+, Ni2+, and Cu2+ have also been determined using potentiometric titration (at I = 0.1 M) and 31P NMR spectroscopy. Heats of protonation of HnBzDPn-4 species have been determined by titration calorimetry. From the temperature dependence of the complex Eu3+-HnBzDPn-4 equilibrium constant, a composite enthalpy (?H = -15.1 (+/-1.0) kJ mol-1) of complexation has been computed. Comparing these thermodynamic parameters with literature reports on other diphosphonic acids and structurally similar carboxylic acids indicates that exothermic heats of complexation are unique to the Eu-BzDP system. Comparisons with thermodynamic data from the literature indicate that the fixed geometry imposed by the benzene ring enhances complex stability.

  3. Changes in the peripheral blood transcriptome associated with occupational benzene exposure identified by cross-comparison on two microarray platforms

    SciTech Connect (OSTI)

    McHale, Cliona M.; Zhang, Luoping; Lan, Qing; Li, Guilan; Hubbard, Alan E.; Forrest, Matthew S.; Vermeulen, Roel; Chen, Jinsong; Shen, Min; Rappaport, Stephen M.; Yin, Songnian; Smith, Martyn T.; Rothman, Nathaniel

    2009-03-01T23:59:59.000Z

    Benzene is an established cause of leukemia and a possible cause of lymphoma in humans but the molecular pathways underlying this remain largely undetermined. This study sought to determine if the use of two different microarray platforms could identify robust global gene expression and pathway changes associated with occupational benzene exposure in the peripheral blood mononuclear cell (PBMC) gene expression of a population of shoe-factory workers with well-characterized occupational exposures to benzene. Microarray data was analyzed by a robust t-test using a Quantile Transformation (QT) approach. Differential expression of 2692 genes using the Affymetrix platform and 1828 genes using the Illumina platform was found. While the overall concordance in genes identified as significantly associated with benzene exposure between the two platforms was 26% (475 genes), the most significant genes identified by either array were more likely to be ranked as significant by the other platform (Illumina = 64%, Affymetrix = 58%). Expression ratios were similar among the concordant genes (mean difference in expression ratio = 0.04, standard deviation = 0.17). Four genes (CXCL16, ZNF331, JUN and PF4), which we previously identified by microarray and confirmed by real-time PCR, were identified by both platforms in the current study and were among the top 100 genes. Gene Ontology analysis showed over representation of genes involved in apoptosis among the concordant genes while Ingenuity{reg_sign} Pathway Analysis (IPA) identified pathways related to lipid metabolism. Using a two-platform approach allows for robust changes in the PBMC transcriptome of benzene-exposed individuals to be identified.

  4. Ex 7.6(a) The vapor pressure of benzene is 400 Torr at 60.6C, but it fell to 386 Torr when 19.0 g of an involatile organic compound was dissolved in 500 g of benzene. Calculate the

    E-Print Network [OSTI]

    Findley, Gary L.

    Ex 7.6(a) The vapor pressure of benzene is 400 Torr at 60.6°C, but it fell to 386 Torr when 19.0 g of an involatile organic compound was dissolved in 500 g of benzene. Calculate the molar mass of the involatile

  5. Phytoremediation of hydrocarbon-contaminated soils: principles and applications

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    Toluene Ethylbenzene CH2CH3 ii) Common Oxygenates MTBE O C CH3CH3 CH3 m-Xylene CH3 CH3 p-Xylene CH3 CH3 CH Ethylbenzene CH2CH3CH2CH3CH2CH3 ii) Common Oxygenates MTBE O C CH3CH3 CH3 m-Xylene CH3 CH3 CH3 CH3 p-Xylene CH3 Ethylbenzene CH2CH3 ii) Common Oxygenates MTBE O C CH3CH3 CH3 m-Xylene CH3 CH3 p-Xylene CH3 CH3 CH3CH2OH

  6. Sodium dodecyl benzene sulfonate-assisted synthesis through a hydrothermal reaction

    SciTech Connect (OSTI)

    Sobhani, Azam [Department of Inorganic Chemistry, Faculty of Chemistry, University of Kashan, Kashan, P.O. Box 87317–51167, Islamic Republic of Iran (Iran, Islamic Republic of)] [Department of Inorganic Chemistry, Faculty of Chemistry, University of Kashan, Kashan, P.O. Box 87317–51167, Islamic Republic of Iran (Iran, Islamic Republic of); Salavati-Niasari, Masoud, E-mail: salavati@kashanu.ac.ir [Department of Inorganic Chemistry, Faculty of Chemistry, University of Kashan, Kashan, P.O. Box 87317–51167, Islamic Republic of Iran (Iran, Islamic Republic of) [Department of Inorganic Chemistry, Faculty of Chemistry, University of Kashan, Kashan, P.O. Box 87317–51167, Islamic Republic of Iran (Iran, Islamic Republic of); Institute of Nano Science and Nano Technology, University of Kashan, Kashan, P.O. Box 87317–51167, Islamic Republic of Iran (Iran, Islamic Republic of)

    2012-08-15T23:59:59.000Z

    Graphical abstract: Reaction of a SeCl{sub 4} aqueous solution with a NiCl{sub 2}·6H{sub 2}O aqueous solution in presence of sodium dodecyl benzene sulfonate (SDBS) as capping agent and hydrazine (N{sub 2}H{sub 4}·H{sub 2}O) as reductant, produces nanosized nickel selenide through a hydrothermal method. The effect of temperature, reaction time and amounts of reductant on the morphology, particle sizes of NiSe nanostructures has been investigated. Highlights: ? NiSe nanostructures were synthesized by hydrothermal method. ? A novel Se source was used to synthesize NiSe. ? SDBS as capping agent plays a crucial role on the morphology of products. ? A mixture of Ni{sub 3}Se{sub 2} and NiSe was prepared in the presence of 2 ml hydrazine. ? A pure phase of NiSe was prepared in the presence of 4 or 6 ml hydrazine. -- Abstract: The effects of the anionic surfactant on the morphology, size and crystallization of NiSe precipitated from NiCl{sub 2}·6H{sub 2}O and SeCl{sub 4} in presence of hydrazine (N{sub 2}H{sub 4}·H{sub 2}O) as reductant were investigated. The products have been successfully synthesized in presence of sodium dodecyl benzene sulfonate (SDBS) as surfactant via an improved hydrothermal route. A variety of synthesis parameters, such as reaction time and temperature, capping agent and amount of reducing agent have a significant effect on the particle size, phase purity and morphology of the obtained products. The sample size became bigger with decreasing reaction temperature and increasing reaction time. In the presence of 2 ml hydrazine, the samples were found to be the mixture of Ni{sub 3}Se{sub 2} and NiSe. With increasing the reaction time and amount of hydrazine a pure phase of hexagonal NiSe was obtained. X-ray diffraction analysis (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM) images indicate phase, particle size and morphology of the products. Chemical composition and purity of the products were characterized by X-ray energy dispersive spectroscopy (EDS). Photoluminescence (PL) was used to study the optical properties of NiSe samples.

  7. An evaluation of the Gilian TRACEAIR Organic Vapor Monitoring Diffusive Badge in measuring short-term exposure levels of benzene under field conditions 

    E-Print Network [OSTI]

    Pierce, Mark Edward

    1996-01-01T23:59:59.000Z

    The objective of this research is to evaluate the performance of the Gilian TRACEAIR Organic Vapor Monitoring I (OVMI) Diffusive Badge in measuring short-term benzene exposures under field conditions. In general, a diffusive badge is a device which...

  8. Adsorption calorimetry and enhanced oil recovery: Three component systems, topical report. [Decyltrimethylammonium bromide/water/sodium bromide methanol/toluene/n-heptane

    SciTech Connect (OSTI)

    Noll, L.A.

    1988-03-01T23:59:59.000Z

    One objective of this project is to determine the adsorptive losses of EOR chemicals on minerals in a systematic manner and expand adsorption models for incorporation as an adsorption module into chemical flooding simulators. The Woodbury-Noll adsorption model was developed which fits both amount and heat of adsorption simultaneously. Two ternary systems were selected with a view to extending the Woodbury-Noll adsorption model to these systems. In the first of these systems, DTAB/NaBr/H20/silica, competitive effects are not present. In the second system, methanol/toluene/heptane/silica, competitive adsoprtion is present. Flow adsorption calorimetry was carried out on these ternary systems and on their respective binaries. Adsorption calorimetry of DTAB from solutions with added electrolyte showed that the heat and the amount of adsorption increased when the salt content was raised to 3 percent, being approximately constant thereafter. However, the increase in salinity above this amount moved the plateau region to lower surfactant concentrations. Adsorption of DTAB at 45)degree)C resulted in lower adsorption than at 25)degree)C, but the heat release was only slightly lower. The heat and amount of adsorption of methanol from heptane onto silica are both markedly reduced by the presence of toluene in the solution. Densities of the surfactant solutions and of the binaries of methanol/toluene/heptane system are reported. 6 refs., 20 figs., 13 tabs.

  9. Photocatalytic degradation of gaseous toluene over TiO{sub 2}-SiO{sub 2} composite nanotubes synthesized by sol-gel with template technique

    SciTech Connect (OSTI)

    Zou, Xuejun [State Key Laboratory of Fine Chemical and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian, 116024 (China)] [State Key Laboratory of Fine Chemical and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian, 116024 (China); Li, Xinyong, E-mail: xyli@dlut.edu.cn [State Key Laboratory of Fine Chemical and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian, 116024 (China) [State Key Laboratory of Fine Chemical and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian, 116024 (China); Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia); Qu, Zhenping; Zhao, Qidong; Shi, Yong; Chen, Yongying [State Key Laboratory of Fine Chemical and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian, 116024 (China)] [State Key Laboratory of Fine Chemical and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian, 116024 (China); Tade, Moses [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia)] [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia); Liu, Shaomin, E-mail: shaomin.liu@curtin.edu.au [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia)] [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia)

    2012-02-15T23:59:59.000Z

    Graphical abstract: TiO{sub 2}-SiO{sub 2} nanotubes (b) were fabricated by sol-gel method using ZnO nanowires (a) as template. Highlights: Black-Right-Pointing-Pointer A simple method to prepare TiO{sub 2}-SiO{sub 2} nanotubes for photocatalytic toluene removal. Black-Right-Pointing-Pointer The TiO{sub 2}-SiO{sub 2} nanotubes have a small blue shift and higher absorption intensity. Black-Right-Pointing-Pointer The TiO{sub 2}-SiO{sub 2} nanotubes have an enhanced photoactivity in degrading gaseous toluene. -- Abstract: TiO{sub 2}-SiO{sub 2} composite nanotubes were successfully synthesized by a facile sol-gel technique utilizing ZnO nanowires as template. The nanotubes were well characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, N{sub 2} adsorption-desorption analysis and UV-vis diffuse reflectance spectroscopy. The nanotubular TiO{sub 2}-SiO{sub 2} composite photocatalysts showed diameter of 300-325 nm, fine mesoporous structure and high specific surface area. The results indicated that the degradation efficiency of gaseous toluene could get 65% after 4 h reaction using the TiO{sub 2}-SiO{sub 2} composite as the photocatalyst under UV light illumination, which was higher than that of P25.

  10. Exposure to methyl tert-butyl ether and benzene among service station attendants and operators

    SciTech Connect (OSTI)

    Hartle, R. [National Inst. for Occupational Safety and Health, Cincinnati, OH (United States)

    1993-12-01T23:59:59.000Z

    Concerns for atmospheric pollution from auto exhaust have led to the blending of {open_quotes}oxygenates{close_quotes} with motor fuels. The most common oxygenate, methyl tert-butyl ether (MTBE) is currently required within several metropolitan areas (Denver and Phoenix) in the range of 12% of the motor fuel. Amendments to the Clean Air Act may expand this requirement to as many as 44 other areas of the United States in the near future. In consideration of the magnitude of potential uncontrolled exposures from its extensive use and a related concern involving the potential influence of MTBE blending on exposures to other constituents of gasoline (particularly benzene), an evaluation of exposures among service station attendants and operators was undertaken at the request, and in cooperation with, the American Petroleum Institute during the latter part of 1990. For application of the survey results to a broad audience, three categories or types of service stations were identified with regard to MTBE use and exposure potential: (a) service stations that do not use MTBE or use it only as an octane enhancer, (b) service stations with seasonal requirements to use 12-15% MTBE (the Denver, Colorado, and Phoenix, Arizona, metropolitan areas), and (c) service stations equipped with stage II (active) vapor recovery systems (several coastal areas, most notably Southern California). 4 refs., 4 tabs.

  11. Benchmark Theoretical Study of the ?–? Binding Energy in the Benzene Dimer

    SciTech Connect (OSTI)

    Miliordos, Evangelos; Apra, Edoardo; Xantheas, Sotiris S.

    2014-09-04T23:59:59.000Z

    We establish a new estimate for the interaction energy between two benzene molecules in the parallel displaced (PD) conformation by systematically converging (i) the intra- and intermolecular geometry at the minimum geometry, (ii) the expansion of the orbital basis set and (iii) the level of electron correlation. The calculations were performed at the second order Møller - Plesset perturbation (MP2) and the Coupled Cluster including Singles, Doubles and a perturbative estimate of Triples replacements [CCSD(T)] levels of electronic structure theory. At both levels of theory, by including results corrected for Basis Set Superposition Error (BSSE), we have estimated the Complete Basis Set (CBS) limit by employing the family of Dunning’s correlation consistent polarized valence basis sets. The largest MP2 calculation was performed with the cc-pV6Z basis set (2,772 basis functions), whereas the largest CCSD(T) calculation with the cc-pV5Z basis set (1,752 basis functions). The cluster geometries were optimized with basis sets up to quadruple-? quality, observing that both its intra- and inter-molecular parts have practically converged with the triple-? quality sets. The use of converged geometries was found to play an important role for obtaining accurate estimates for the CBS limits. Our results demonstrate that the binding energies with the families of the plain (cc-pVnZ) and augmented (aug-cc-pVnZ) sets converge [to within < 0.01 kcal/mol for MP2 and < 0.15 kcal/mol for CCSD(T)] to the same CBS limit. In addition, the average of the uncorrected and BSSEcorrected binding energies was found to converge to the same CBS limit must faster than either of the two constituents (uncorrected or BSSE-corrected binding energies). Due to the fact that the family of augmented basis sets (especially for the larger sets) causes serious linear dependency problems, the plain basis sets (for which no linear dependencies were found) are deemed as a more efficient and straightforward path for obtaining an accurate CBS limit. We considered extrapolations of the uncorrected (?𝐸) and BSSE-corrected (?𝐸!") binding energies, their average value (?𝐸!"#) as well as the average of the latter over the plain and augmented sets (?𝐸!"#) with the cardinal number of the basis set n. Our best estimate of the CCSD(T)/CBS limit for the ?-? interaction energy in the PD benzene dimer is De = 2.65 ± 0.02 kcal/mol. The best CCSD(T)/cc-pV5Z calculated value is 2.62 kcal/mol, just 0.03 kcal/mol away from the CBS limit. For comparison, the MP2/CBS limit estimate is 5.00 ± 0.01 kcal/mol, demonstrating a 90% overbinding with respect to CCSD(T). The Spin-Component-Scaled (SCS) MP2 variant was found to closely reproduce the CCSD(T) results for each basis set, while Scaled-Opposite-Spin (SOS) yielded results that are too low when compared to CCSD(T).

  12. Laboratory investigations of the interaction between benzene and bare silicate grain surfaces

    E-Print Network [OSTI]

    J. D. Thrower; M. P. Collings; F. J. M. Rutten; M. R. S. McCoustra

    2008-12-17T23:59:59.000Z

    Experimental results on the thermal desorption of benzene (C6H6) from amorphous silica (SiO2) are presented. The amorphous SiO2 substrate was imaged using atomic force microscopy (AFM), revealing a surface morphology reminiscent of that of interplanetary dust particles (IDPs). Temperature programmed desorption (TPD) experiments were conducted for a wide range of C6H6 exposures, yielding information on both C6H6-SiO2 interactions and the C6H6-C6H6 interactions present in the bulk C6H6 ice. The low coverage experiments reveal complicated desorption behaviour that results both from porosity and roughness in the SiO2 substrate, and repulsive interactions between C6H6 molecules. Kinetic parameters were obtained through a combination of direct analysis of the TPD traces and kinetic modelling, demonstrating the coverage dependence of both desorption energy and pre-exponential factor. Experiments were also performed whereby the pores were blocked by pre-exposure of the SiO2 to water vapour. C6H6 was observed to be adsorbed preferentially on the SiO2 film not covered by H2O at the temperature at which these experiments were performed. This observation means that intermolecular repulsion likely becomes important at smaller C6H6 exposures on grains with a H2O mantle. Kinetic modelling of C6H6 multilayer desorption yields kinetic parameters in good agreement with previous studies, with the SiO2 having little impact on the desorption beyond the first few layers.

  13. Effect of Ethanol and Methyl-tert-Butyl Ether on Monoaromatic Hydrocarbon Biodegradation: Response Variability for Different Aquifer Materials Under Various Electron-Accepting Conditions

    SciTech Connect (OSTI)

    Ruiz-Aguilar, G L; Fernandez-Sanchez, J M; Kane, S R; Kim, D; Alvarez, P J

    2003-10-06T23:59:59.000Z

    Aquifer microcosms were used to determine how ethanol and methyl-tert-butyl ether (MtBE) affect monoaromatic hydrocarbon degradation under different electron-accepting conditions commonly found in contaminated sites experiencing natural attenuation. Response variability was investigated by using aquifer material from four sites with different exposure history. The lag phase prior to BTEX (benzene, toluene, ethylbenzene, and xylenes) and ethanol degradation was typically shorter in microcosms with previously contaminated aquifer material, although previous exposure did not always result in high degradation activity. Toluene was degraded in all aquifer materials and generally under a broader range of electron-accepting conditions compared to benzene, which was degraded only under aerobic conditions. MtBE was not degraded within 100 days under any condition, and it did not affect BTEX or ethanol degradation patterns. Ethanol was often degraded before BTEX compounds, and had a variable effect on BTEX degradation as a function of electron-accepting conditions and aquifer material source. An occasional enhancement of toluene degradation by ethanol occurred in denitrifying microcosms with unlimited nitrate; this may be attributable to the fortuitous growth of toluene-degrading bacteria during ethanol degradation. Nevertheless, experiments with flow-through aquifer columns showed that this beneficial effect could be eclipsed by an ethanol-driven depletion of electron acceptors, which significantly inhibited BTEX degradation and is probably the most important mechanism by which ethanol could hinder BTEX natural attenuation. A decrease in natural attenuation could increase the likelihood that BTEX compounds reach a receptor as well as the potential duration of exposure.

  14. Ground rubber: Reactive permeable barrier sorption media

    SciTech Connect (OSTI)

    Kershaw, D.S.; Pamukcu, S. [Lehigh Univ., Bethlehem, PA (United States)

    1997-12-31T23:59:59.000Z

    The objective of this research was to examine the feasibility of using ground tire rubber as a sorbent media in reactive permeable barrier systems. Previous research by the current authors has demonstrated that tire rubber can sorb significant quantities of benzene, toluene, ethylbenzene and O-xylene from aqueous solutions. The current research was run to examine the usage rate of ground rubber in a packed bed reactor under specific contact times. In addition, desorption and repetitive sorption tests were run to determine the reversibility of the sorption process for ground tire rubber. These tests were run to determine the regeneration capacity of ground tire rubber. Results of the study show that the usage rates are greater than 50% with an empty bed contact times of 37 minutes, and minimal amounts of energy are needed to regenerate the tire rubber after use.

  15. Reduce emissions and operating costs with appropriate glycol selection

    SciTech Connect (OSTI)

    Covington, K.; Lyddon, L. [Bryan Research and Engineering, Inc., TX (United States); Ebeling, H. [Latoka Engineering L.L.C., Tulsa, OK (United States)

    1998-12-31T23:59:59.000Z

    Benzene, toluene, ethylbenzene and xylene (BTEX) emissions from glycol dehydration units have become a major concern and some form of control is necessary in many cases. One method of reducing BTEX emissions that is often overlooked is in the selection of the proper dehydrating agent. BTEX compounds are less soluble in diethylene glycol (DEG) than triethylene glycol (TEG) and considerably less soluble in ethylene glycol (EG). If the use of DEG or EG achieves the required gas dew point in cases where BTEX emissions are a concern, a significant savings in both operating costs and the cost of treating still vent gases may be achieved. This paper compares plant operations using TEG, DEG and EG from the viewpoint of BTEX emissions, circulating rates, utilities and dehydration capabilities.

  16. Eielson Air Force Base Operable Unit 2 baseline risk assessment

    SciTech Connect (OSTI)

    Lewis, R.E.; Jarvis, T.T.; Jarvis, M.R.; Whelan, G.

    1994-10-01T23:59:59.000Z

    Operable Unit 2 at Eielson Air Force Base (AFB) near Fairbanks, is one of several operable units characterized by petroleum, oil, and lubricant contamination, and by the presence of organic products floating at the water table, as a result of Air Force operations since the 1940s. The base is approximately 19,270 acres in size, and comprises the areas for military operations and a residential neighborhood for military dependents. Within Operable Unit 2, there are seven source areas. These source areas were grouped together primarily because of the contaminants released and hence are not necessarily in geographical proximity. Source area ST10 includes a surface water body (Hardfill Lake) next to a fuel spill area. The primary constituents of concern for human health include benzene, toluene, ethylbenzene, and xylenes (BTEX). Monitored data showed these volatile constituents to be present in groundwater wells. The data also showed an elevated level of trace metals in groundwater.

  17. In situ thermally enhanced biodegradation of petroleum fuel hydrocarbons and halogenated organic solvents

    DOE Patents [OSTI]

    Taylor, Robert T. (Livermore, CA); Jackson, Kenneth J. (San Leandro, CA); Duba, Alfred G. (Livermore, CA); Chen, Ching-I (Danville, CA)

    1998-01-01T23:59:59.000Z

    An in situ thermally enhanced microbial remediation strategy and a method for the biodegradation of toxic petroleum fuel hydrocarbon and halogenated organic solvent contaminants. The method utilizes nonpathogenic, thermophilic bacteria for the thermal biodegradation of toxic and carcinogenic contaminants, such as benzene, toluene, ethylbenzene and xylenes, from fuel leaks and the chlorinated ethenes, such as trichloroethylene, chlorinated ethanes, such as 1,1,1-trichloroethane, and chlorinated methanes, such as chloroform, from past solvent cleaning practices. The method relies on and takes advantage of the pre-existing heated conditions and the array of delivery/recovery wells that are created and in place following primary subsurface contaminant volatilization efforts via thermal approaches, such as dynamic underground steam-electrical heating.

  18. In situ thermally enhanced biodegradation of petroleum fuel hydrocarbons and halogenated organic solvents

    DOE Patents [OSTI]

    Taylor, R.T.; Jackson, K.J.; Duba, A.G.; Chen, C.I.

    1998-05-19T23:59:59.000Z

    An in situ thermally enhanced microbial remediation strategy and a method for the biodegradation of toxic petroleum fuel hydrocarbon and halogenated organic solvent contaminants are described. The method utilizes nonpathogenic, thermophilic bacteria for the thermal biodegradation of toxic and carcinogenic contaminants, such as benzene, toluene, ethylbenzene and xylenes, from fuel leaks and the chlorinated ethenes, such as trichloroethylene, chlorinated ethanes, such as 1,1,1-trichloroethane, and chlorinated methanes, such as chloroform, from past solvent cleaning practices. The method relies on and takes advantage of the pre-existing heated conditions and the array of delivery/recovery wells that are created and in place following primary subsurface contaminant volatilization efforts via thermal approaches, such as dynamic underground steam-electrical heating. 21 figs.

  19. Superfund Record of Decision (EPA Region 2): Hertel Landfill, town of Plattekill, Ulster County, NY. (First remedial action), September 1991. Final report

    SciTech Connect (OSTI)

    Not Available

    1991-09-27T23:59:59.000Z

    The 80-acre Hertel Landfill site consists of a 13-acre former municipal landfill and adjacent land in Plattekill, Ulster County, New York. The site overlies two natural aquifers. In 1976, the site was shut down for a variety of violations, including illegal dumping of industrial wastes and violating a town ordinance prohibiting the disposal of non-local waste. As a result of these improper disposal practices, a number of State investigations were conducted, which identified contamination by various organic compounds and metals in the onsite soil and ground water. The Record of Decision (ROD) addresses soil contaminated by landfill wastes, and ground water contaminated by landfill leachate. The primary contaminants of concern affecting the soil, sediment, debris, and ground water are VOCs including benzene, toluene, and xylenes; other organics including phenols; and metals including arsenic, chromium, and lead. The selected remedial action for the site is included.

  20. Photocatalytic degradation of gaseous toluene over hollow “spindle-like” ?-Fe{sub 2}O{sub 3} loaded with Ag

    SciTech Connect (OSTI)

    Li, Hong [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China) [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China); Department of Basic, Dalian Naval Academy, Dalian 116018 (China); Zhao, Qidong [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China)] [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China); Li, Xinyong, E-mail: xyli@dlut.edu.cn [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China) [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China); Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia); Shi, Yong [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China)] [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China); Zhu, Zhengru [Research Center of Hydrology and Engineering, Academy of City and Environment, Liaoning Normal University, Dalian 116029 (China)] [Research Center of Hydrology and Engineering, Academy of City and Environment, Liaoning Normal University, Dalian 116029 (China); Tade, Moses [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia)] [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia); Liu, Shaomin, E-mail: shaomin.liu@curtin.edu.au [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia)] [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia)

    2012-06-15T23:59:59.000Z

    Highlights: ? Hollow ?-Fe{sub 2}O{sub 3} spindle-shaped microparticles were prepared for Ag support. ? The hollow ?-Fe{sub 2}O{sub 3} and Ag/?-Fe{sub 2}O{sub 3} materials were used to degrade gaseous toluene. ? Complete degradation of toluene occurred on the Ag/?-Fe{sub 2}O{sub 3} surface. -- Abstract: In this work, hollow “spindle-like” ?-Fe{sub 2}O{sub 3} nanoparticles were synthesized by a hydrothermal route. The Ag/?-Fe{sub 2}O{sub 3} catalyst was prepared based on the spindle-shaped ?-Fe{sub 2}O{sub 3} with CTAB as the surfactant, which showed excellent photoelectric property and photocatalytic activity. The structural properties of these samples were systematically investigated by X-ray powder diffraction, scanning electronic microscopy, transmission electronic microscopy, energy-dispersive X-ray spectra, and UV–Vis diffuse reflectance spectroscopy techniques. The photo-induced charge separation in the samples was demonstrated by surface photovoltage measurement. The photocatalytic performances of the Ag/?-Fe{sub 2}O{sub 3} and ?-Fe{sub 2}O{sub 3} samples were comparatively studied in the degradation of toluene under xenon lamp irradiation by in situ FTIR spectroscopy. Benzaldehyde and benzoic acid species could be observed on the ?-Fe{sub 2}O{sub 3} surface rather than Ag/?-Fe{sub 2}O{sub 3} surface. The results indicate that the Ag/?-Fe{sub 2}O{sub 3} sample exhibited higher photocatalytic efficiency.

  1. Raman Spectroscopy of the Reaction of Thin Films of Solid-State Benzene with Vapor-Deposited Ag, Mg, and Al

    SciTech Connect (OSTI)

    Schalnat, Matthew C. [Univ. of Arizona, Tucson, AZ (United States). Dept. of Chemistry and Biochemistry; Hawkridge, Adam M. [Univ. of Arizona, Tucson, AZ (United States). Dept. of Chemistry and Biochemistry; Pemberton, Jeanne E. [Univ. of Arizona, Tucson, AZ (United States). Dept. of Chemistry and Biochemistry

    2011-07-21T23:59:59.000Z

    Thin films of solid-state benzene at 30 K were reacted with small quantities of vapor-deposited Ag, Mg, and Al under ultrahigh vacuum, and products were monitored using surface Raman spectroscopy. Although Ag and Mg produce small amounts of metal–benzene adduct products, the resulting Raman spectra are dominated by surface enhancement of the normal benzene modes from metallic nanoparticles suggesting rapid Ag or Mg metallization of the film. In contrast, large quantities of Al adduct products are observed. Vibrational modes of the products in all three systems suggest adducts that are formed through a pathway initiated by an electron transfer reaction. The difference in reactivity between these metals is ascribed to differences in ionization potential of the metal atoms; ionization potential values for Ag and Mg are similar but larger than that for Al. These studies demonstrate the importance of atomic parameters, such as ionization potential, in solid-state metal–organic reaction chemistry.

  2. Multielectron effects in high harmonic generation in N_2 and benzene: simulation using a non-adiabatic quantum molecular dynamics approach for laser-molecule interactions

    E-Print Network [OSTI]

    Dundas, Daniel

    2012-01-01T23:59:59.000Z

    A mixed quantum-classical approach is introduced which allows the dynamically response of molecules driven far from equilibrium to be modeled. This method is applied here to the interaction of molecules with intense, short-duration laser pulses. The electronic response of the molecule is described using time-dependent density functional theory (TDDFT) and the resulting Kohn-Sham equations are solved numerically using finite difference techniques in conjunction with local and global adaptations of an underlying grid in curvilinear coordinates. Using this approach, simulations can be carried out for a wide range of molecules and both all-electron and pseudopotential calculations can be performed. The approach is applied to the study of high harmonic generation in N_2 and benzene using linearly-polarized laser pulses and to the best of our knowledge, the results for benzene represent the first TDDFT calculations of high harmonic generation in benzene using linearly polarized laser pulses. For N_2 an enhancement ...

  3. Facile preparation of sphere-like copper ferrite nanostructures and their enhanced visible-light-induced photocatalytic conversion of benzene

    SciTech Connect (OSTI)

    Shen, Yu, E-mail: shenyuqing0322@gmail.com [School of Environmental and Chemical Engineering, Dalian Jiaotong University, Dalian 116028 (China); Key Laboratory of Industrial Ecology and Environmental Engineering and State Key Laboratory of Fine Chemical, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China); Wu, Yanbo; Xu, Hongfeng; Fu, Jie [School of Environmental and Chemical Engineering, Dalian Jiaotong University, Dalian 116028 (China); Li, Xinyong; Zhao, Qidong; Hou, Yang [Key Laboratory of Industrial Ecology and Environmental Engineering and State Key Laboratory of Fine Chemical, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China)

    2013-10-15T23:59:59.000Z

    Graphical abstract: - Highlights: • Spinel CuFe{sub 2}O{sub 4} nanospheres were successfully synthesized via a facile method. • CuFe{sub 2}O{sub 4} nanospheres showed high photocatalytic activity toward benzene. • Ethyl acetate, carboxylic acid and aldehyde were the intermediate products. - Abstract: Spinel copper ferrite nanospheres with diameters of about 116 nm were synthesized in high yield via a facile solvothermal route. The prepared nanospheres had cubic spinel structure and exhibited good size uniformity and regularity. The band-gap energy of CuFe{sub 2}O{sub 4} nanospheres was calculated to be about 1.69 eV, indicating their potential visible-light-induced photocatalytic activity. The dramatically enhanced photocatalytic activity of the CuFe{sub 2}O{sub 4} nanospheres was evaluated via the photocatalytic conversion of benzene under Xe lamp irradiation. By using the in situ FTIR technique, ethyl acetate, carboxylic acid and aldehyde could be regarded as the intermediate products, and CO{sub 2} was produced as the final product during the reaction process. This study provided new insight into the design and preparation of functional nanomaterials with sphere structure in high yield, and the as-grown architectures demonstrated an excellent ability to remove organic pollutants in the atmosphere.

  4. Broad specificity dioxygenase enzymes and the bioremediation of hazardous aromatic pollutants

    SciTech Connect (OSTI)

    Bonus, P.A.; Nies, L. [Purdue Univ., West Lafayette, IN (United States)

    1996-11-01T23:59:59.000Z

    The release of aromatic compounds to the environment is a major source of global pollution. In particular, the contamination of soil and groundwater with benzene, toluene, and xylenes (BTX) is the most ubiquitous form of aromatic pollution. The major source of BTX contamination is the release of gasoline and other petroleum products. This research focused on the improvement of bioremediation of BTX through a better understanding of broad specificity dioxygenase enzymes produced by soil and sediment bacteria. The investigation utilized pure bacterial strains isolated on biphenyl, naphthalene, or toluene. These isolated aerobic bacteria were then used to investigate the specificity of the initial enzymatic attack on aromatic compounds including BTX and polychlorinated biphenyls (PCBs). The enzymatic specificity and competency of the five isolates selected for study were determined through the use of growth tests and two rapid assay techniques. The growth tests were conducted on mineral agar plates or in liquid cultures, and they were used to determine substrate specificity. In addition, rapid assays for both BTX and PCBs were carried out using various growth substrates. These assays allowed further clarification of the specificity of the dioxygenase enzymes involved in aromatic degradation. Preliminary results of the PCB assay show that biphenyl and naphthalene isolated organisms grown on biphenyl, benzoate, naphthalene, and succinate maintain production of broad specificity dioxygenase enzymes able to degrade PCBs. Likewise, the BTX assay confirms that biphenyl and naphthalene selected organisms grown on their respective selection substrates completely degrade BTX including all three xylene isomers. In comparison, the toluene selected organism that was studied was unable to degrade PCBs, but it was able to degrade all BTX constituents.

  5. aux interfaces liquide: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (81 C), its relative safety (compared to liquids such as benzene and toluene of graphite under water and under cyclohexane will be discussed. From the results of this...

  6. aux interfaces solide-liquide: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (81 C), its relative safety (compared to liquids such as benzene and toluene of graphite under water and under cyclohexane will be discussed. From the results of this...

  7. Hanna, S.R., D. Heinold, R. Paine, H.C. Frey, D. Baker, R. Karp, and H. Feldman, "A Monte Carlo Study of the Uncertainties in Predictions by ISC3ST and AERMOD of Annual Average Benzene and 1,3-Butadiene Concentrations

    E-Print Network [OSTI]

    Frey, H. Christopher

    Study of the Uncertainties in Predictions by ISC3ST and AERMOD of Annual Average Benzene and 1 of Annual Average Benzene and 1,3-Butadiene Concentrations around the Houston Ship Channel Control # 735 is on uncertainties in ISC3ST and AERMOD predictions of annual averaged concentrations of benzene and 1,3-butadiene

  8. SIGMA-ALDRICH MATERIAL SAFETY DATA SHEET

    E-Print Network [OSTI]

    Choi, Kyu Yong

    (Polish) * Methyl toluene * NCI-C55232 * RCRA waste number U239 * Violet 3 * Xiloli (Italian) * Xylene fumes under fire conditions. Specific Method(s) of Fire Fighting: Use water spray to cool fire-exposed

  9. Tracking a defined route for O2 migration in a dioxygen-activating diiron enzyme

    E-Print Network [OSTI]

    Song, Woon Ju

    For numerous enzymes reactive toward small gaseous compounds, growing evidence indicates that these substrates diffuse into active site pockets through defined pathways in the protein matrix. Toluene/o-xylene monooxygenase ...

  10. Structural investigations of hydroxylase proteins and complexes in bacterial multicomponent monooxygenase systems

    E-Print Network [OSTI]

    McCormick, Michael S. (Michael Scott)

    2008-01-01T23:59:59.000Z

    Bacterial multicomponent monooxgenases (BMMs) such as toluene/o-xylene monooxygenase (ToMO), phenol hydroxylase (PH), and soluble methane monooxygenase (sMMO) catalyze hydrocarbon oxidation reactions at a carboxylatebridged ...

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

    SciTech Connect (OSTI)

    Zhong, Lirong; Cantrell, Kirk J.; Mitroshkov, Alexandre V.; Shewell, Jesse L.

    2014-05-06T23:59:59.000Z

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

  12. Superfund innovative technology evaluation (site) program evaluation report for antox BTX water screen (BTX immunoassay)

    SciTech Connect (OSTI)

    Gerlach, R.W.; White, R.J.; O'Leary, N.F.; Van Emon, J.M.

    1993-06-01T23:59:59.000Z

    The results of a demonstration of a portable immunoassay for the detection of benzene, toluene, and xylene(s) (BTX) are described in the report. Seventy-nine field samples were obtained from monitoring wells at several sites with gasoline contaminated ground water. Sample splits were analyzed on-site by the BTX immunoassay and in the laboratory by gas chromatography (GC) using EPA Method 8020. The BTX immunoassay was rapid and simple to use. It performed well in identifying high level contamination and gasoline contaminated samples having BTX concentrations greater than 100 ppb. It did not fully meet the claims of the developer of identifying contamination levels down to 25 ppb BTX. Two field samples determined by GC to have between 25 and 100 ppb BTX failed to be classified correctly by the immunoassay. Results from quality assurance samples with BTX concentrations of 2.5, 25, and 100 ppb also showed that false negative results would be expected at higher than a 5 percent rate when BTX contamination levels were between 25 and 100 ppb. However, for samples with higher BTX levels, the immunoassay gave excellent results. Two field samples yielded false positive results compared to GC values, but these samples showed signs of low-level gasoline contamination.

  13. A density functional theory study of magneto-electric Jones birefringence of noble gases, furan homologues, and mono-substituted benzenes

    SciTech Connect (OSTI)

    Fahleson, Tobias; Norman, Patrick, E-mail: panor@ifm.liu.se [Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping (Sweden); Coriani, Sonia, E-mail: coriani@units.it [Dipartimento di Scienze Chimiche e Farmaceutiche, Università degli Studi di Trieste, I-34127 Trieste (Italy); Rizzo, Antonio, E-mail: rizzo@ipcf.cnr.it [CNR - Consiglio Nazionale delle Ricerche, Istituto per i Processi Chimico Fisici (IPCF-CNR), UOS di Pisa, I-56124 Pisa (Italy); Rikken, Geert L. J. A., E-mail: geert.rikken@lncmi.cnrs.fr [Laboratoire National des Champs Magnétiques Intenses, UPR3228, CNRS/INSA/UJF/UPS, Toulouse and Grenoble (France)

    2013-11-21T23:59:59.000Z

    We report on the results of a systematic ab initio study of the Jones birefringence of noble gases, of furan homologues, and of monosubstituted benzenes, in the gas phase, with the aim of analyzing the behavior and the trends within a list of systems of varying size and complexity, and of identifying candidates for a combined experimental/theoretical study of the effect. We resort here to analytic linear and nonlinear response functions in the framework of time-dependent density functional theory. A correlation is made between the observable (the Jones constant) and the atomic radius for noble gases, or the permanent electric dipole and a structure/chemical reactivity descriptor as the para Hammett constant for substituted benzenes.

  14. Electrical conductivity and equation of state of liquid nitrogen, oxygen, benzene, and 1-butene shocked to 60 GPa

    SciTech Connect (OSTI)

    Hamilton, D.C.

    1986-10-08T23:59:59.000Z

    Measurements are reported for the electrical conductivity of liquid nitrogen (N/sub 2/), oxygen (O/sub 2/) and benzene (C/sub 6/H/sub 6/), and Hugoniot equation of state of liquid 1-butene (C/sub 4/H/sub 8/) under shock compressed conditions. The conductivity data span 7 x 10/sup -4/ to 7 x 10/sup 1/ ..cap omega../sup -1/cm/sup -1/ over a dynamic pressure range 18.1 to 61.5 GPa and are discussed in terms of amorphous semiconduction models which include such transport phenomena as hopping, percolation, pseudogaps, and metallization. Excellent agreement is found between the equation-of-state measurements, which span a dynamic pressure range 12.3 to 53.8 GPa, and Ree's calculated values which assume a 2-phase mixture consisting of molecular hydrogen and carbon in a dense diamond-like phase. There is a 2-1/2 fold increase in the thermal pressure contribution over a less dense, stoichiometrically equivalent liquid. 90 refs., 48 figs., 8 tabs.

  15. A carbon foam with a bimodal micro–mesoporous structure prepared from larch sawdust for the gas-phase toluene adsorption

    SciTech Connect (OSTI)

    Liu, Shouxin, E-mail: liushouxin@126.com [Key Laboratory of Bio-Based Material Science and Technology of The Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Huang, Zhanhua; Wang, Rui [Key Laboratory of Bio-Based Material Science and Technology of The Ministry of Education, Northeast Forestry University, Harbin 150040 (China)

    2013-07-15T23:59:59.000Z

    Highlights: ? Network carbon foam containing a bimodal pore distribution was prepared from Larch. ? Liquefaction route was used for the preparation of morphology controllable carbon. ? Pore structure of carbon foam was controlled through KOH activation. - Abstract: A carbon foam with a bimodal micro–mesopore distribution, was prepared by submitting larch sawdust to liquefaction, resinification, foaming, carbonization and KOH activation. The morphology, pore texture and crystal microstructure was characterized by scanning and transmission electron microscopy, nitrogen adsorption analysis and X-ray powder diffraction. A honeycomb structure with adjacent cells was observed for the precursor of carbon foam. After KOH activation, the cell wall of precursor shrunk and broke. This lead to the formation of a well-connected 3D network and developed ligament pore structure (surface area of 554–1918 m{sup 2}/g) containing bimodal pores, 2.1 and 3.9 nm in diameter. The porous carbon foam prepared at 700 °C exhibited a much higher gas-phase toluene removal than commercial activated carbon fiber owing to the 3D network and bimodal pore structure.

  16. Biodegradation 10: 331340, 1999. 2000 Kluwer Academic Publishers. Printed in the Netherlands.

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    patterns when microbes are exposed to different BTEXN mix- tures. For example, toluene, which is generally. Abstract This work investigated the biodegradation capabilities of indigenous microorganisms exposed specificity of 55 strains. Toluene was the most commonly degraded compound, followed by p-xylene, m

  17. Indoor Air Quality Survey of Boston Nail Salons

    E-Print Network [OSTI]

    Fraden, Seth

    ) suggest that spontaneous abortion in workers exposed to toluene may occur nearly 3 times more than salon owners and workers Nail salon employees are of reproductive age and are exposed to chemicals and Health Xylene, toluene, acetone, and methyl ethyl ketone in nail polishes and hardeners are neurological

  18. Benzene-derived N2-(4-hydroxyphenyl)-deoxyguanosine adduct: UvrABC incision and its conformation in DNA

    SciTech Connect (OSTI)

    Hang, Bo; Rodriguez, Ben; Yang, Yanu; Guliaev, Anton B.; Chenna, Ahmed

    2010-06-14T23:59:59.000Z

    Benzene, a ubiquitous human carcinogen, forms DNA adducts through its metabolites such as p-benzoquinone (p-BQ) and hydroquinone (HQ). N(2)-(4-Hydroxyphenyl)-2'-deoxyguanosine (N(2)-4-HOPh-dG) is the principal adduct identified in vivo by (32)P-postlabeling in cells or animals treated with p-BQ or HQ. To study its effect on repair specificity and replication fidelity, we recently synthesized defined oligonucleotides containing a site-specific adduct using phosphoramidite chemistry. We here report the repair of this adduct by Escherichia coli UvrABC complex, which performs the initial damage recognition and incision steps in the nucleotide excision repair (NER) pathway. We first showed that the p-BQ-treated plasmid was efficiently cleaved by the complex, indicating the formation of DNA lesions that are substrates for NER. Using a 40-mer substrate, we found that UvrABC incises the DNA strand containing N(2)-4-HOPh-dG in a dose- and time-dependent manner. The specificity of such repair was also compared with that of DNA glycosylases and damage-specific endonucleases of E. coli, both of which were found to have no detectable activity toward N(2)-4-HOPh-dG. To understand why this adduct is specifically recognized and processed by UvrABC, molecular modeling studies were performed. Analysis of molecular dynamics trajectories showed that stable G:C-like hydrogen bonding patterns of all three Watson-Crick hydrogen bonds are present within the N(2)-4-HOPh-G:C base pair, with the hydroxyphenyl ring at an almost planar position. In addition, N(2)-4-HOPh-dG has a tendency to form more stable stacking interactions than a normal G in B-type DNA. These conformational properties may be critical in differential recognition of this adduct by specific repair enzymes.

  19. Interdisciplinary investigation of subsurface contaminant transport and fate at point-source releases of gasoline containing MTBE

    SciTech Connect (OSTI)

    Buxton, H.T.; Baehr, A.L. [Geological Survey, West Trenton, NJ (United States); Landmeyer, J.E. [Geological Survey, Columbia, SC (United States)] [and others

    1997-12-31T23:59:59.000Z

    Methyl tert-butyl ether (MTBE) is commonly found at concentrations above the current U.S. Environmental Protection Agency draft lifetime health advisory for drinking water (20 to 200 micrograms per liter) at many point-source gasoline release sites. MTBE is significantly more persistent than benzene, toluene, ethyl-benzene and xylenes (BTEX) in the subsurface. Therefore, evaluation of the implications of its presence in gasoline to monitored natural attenuation and engineered bioremediation alternatives is warranted. An interdisciplinary, field-based investigation of the subsurface transport and fate of MTBE and petroleum hydrocarbons is being conducted by the U.S. Geological Survey (USGS) Toxic Substances Hydrology Program at the site of an underground gasoline storage-tank release near Beaufort, South Carolina. The objective of the investigation is to provide a systematic evaluation of natural attenuation of MTBE compared to BTEX. Results of the field and laboratory studies at this site will be generalized to a broader range of hydrogeochemical conditions through experiments at other sites. Furthermore, newly developed methods of analysis can be applied to sites across the Nation. This investigation of MTBE at point-source release sites is coordinated with investigations of the occurrence of MTBE in shallow ground water, surface water, precipitation, and the atmosphere being conducted by the USGS National Water-Quality Assessment Program.

  20. Introducing constricted variational density functional theory in its relaxed self-consistent formulation (RSCF-CV-DFT) as an alternative to adiabatic time dependent density functional theory for studies of charge transfer transitions

    SciTech Connect (OSTI)

    Krykunov, Mykhaylo; Seth, Mike; Ziegler, Tom [Department of Chemistry, University of Calgary, University Drive 2500, Calgary, Alberta T2N 1N4 (Canada)] [Department of Chemistry, University of Calgary, University Drive 2500, Calgary, Alberta T2N 1N4 (Canada)

    2014-05-14T23:59:59.000Z

    We have applied the relaxed and self-consistent extension of constricted variational density functional theory (RSCF-CV-DFT) for the calculation of the lowest charge transfer transitions in the molecular complex X-TCNE between X = benzene and TCNE = tetracyanoethylene. Use was made of functionals with a fixed fraction (?) of Hartree-Fock exchange ranging from ? = 0 to ? = 0.5 as well as functionals with a long range correction (LC) that introduces Hartree-Fock exchange for longer inter-electronic distances. A detailed comparison and analysis is given for each functional between the performance of RSCF-CV-DFT and adiabatic time-dependent density functional theory (TDDFT) within the Tamm-Dancoff approximation. It is shown that in this particular case, all functionals afford the same reasonable agreement with experiment for RSCF-CV-DFT whereas only the LC-functionals afford a fair agreement with experiment using TDDFT. We have in addition calculated the CT transition energy for X-TCNE with X = toluene, o-xylene, and naphthalene employing the same functionals as for X = benzene. It is shown that the calculated charge transfer excitation energies are in as good agreement with experiment as those obtained from highly optimized LC-functionals using adiabatic TDDFT. We finally discuss the relation between the optimization of length separation parameters and orbital relaxation in the RSCF-CV-DFT scheme.

  1. Qualitative vs. quantitative data: Controls on the accuracy of PID field screening in petroleum contamination assessment applications

    SciTech Connect (OSTI)

    Luessen, M.J.; Allex, M.K.; Holzel, F.R. [ATEC Associates Inc., Cincinnati, OH (United States)

    1995-09-01T23:59:59.000Z

    The use of photoionization detectors (PIDs) for field screening of soils for volatile organic contaminants has become a standard industry practice. PID screening data is generally utilized as a qualitative basis for selection of samples for laboratory analysis to quantify concentrations of specific contaminants of concern. Both qualitative field screening data and quantitative laboratory analytical data were reviewed for more than 100 hydrogeologic assessment sites in Ohio to evaluate controls on the effectiveness of field screening data. Assessment data evaluated was limited to sites at which the suspected contaminant source was a gasoline underground storage tanks system. In each case, a 10.0 eV (or greater) PID calibrated for benzene was used to screen soils which were analyzed for benzene, toluene, ethylbenzene and xylene (BTEX) by SW 846 method 8020. Controls on field screening which were evaluated for each site included (1) soil classification, (2) soil moisture, (3) weather conditions, (4) background levels, (5) equipment quality, (6) screening methodology, and (7) laboratory QA/QC. Statistical data analysis predictably indicated a general overestimate of total BTEX levels based on field screening (gasoline is approximately 25 weight percent BTEX). However, data locally indicated cases of both significant (i.e., more than an order of magnitude difference) over- and under-estimation of actual BTEX concentrations (i.e., quantitative laboratory data) by field screening data.

  2. Baytown Energy Project

    E-Print Network [OSTI]

    Porter, J.

    2006-01-01T23:59:59.000Z

    which maximize the yield of saleable products. Distillation towers consume most of the energy required for aromatics separation. BEP reconfigured the existing towers in the product recovery section to a new fractionation scheme. The new... and toluene sidestream from the primary benzene recovery tower. The result was a 30% reduction in energy in the benzene/toluene fractionation area. The project also debottlenecked the toluene disproportionation unit by 20%. The project was completed...

  3. Atomic Structures of Graphene, Benzene and Methane with Bond Lengths as Sums of the Single, Double and Resonance Bond Radii of Carbon

    E-Print Network [OSTI]

    Raji Heyrovska

    2008-04-25T23:59:59.000Z

    Two dimensional layers of graphene are currently drawing a great attention in fundamental and applied nanoscience. Graphene consists of interconnected hexagons of carbon atoms as in graphite. This article presents for the first time the structures of graphene at the atomic level and shows how it differs from that of benzene, due to the difference in the double bond and resonance bond based radii of carbon. The carbon atom of an aliphatic compound such as methane has a longer covalent single bond radius as in diamond. All the atomic structures presented here have been drawn to scale.

  4. Characterization Of The Hydrogenation Products Of Bix (phenylethynyl) Benzene (DEB) Getter Using Combined GC/FTIR/MS, FT-Raman, and ATR Spectroscopies (U)

    SciTech Connect (OSTI)

    Smyrl, N. R.; Powell, G. L.

    2011-06-09T23:59:59.000Z

    Organic hydrogen getters are utilized to minimize hydrogen accumulation in sealed systems where such build up could produce either a safety problem from pressure build up or corrosion problem due the hydriding of metals contained in the sealed vessel. DEB (1,4 bis (phenyl ethynyl) benzene) is a hydrogen getter that is based on the palladium catalyzed hydrogenation of triple bonds to single bonds in aromatic aryl compound. DEB is a getter mixed with 25% carbon and 1% Pd and pressed into pellets with some porosity. The reaction mechanisms are complex involving solid state reactions with a heterogeneous catalyst leading to the many intermediates.

  5. An analysis of van der Waals density functional components: Binding and corrugation of benzene and C60 on boron nitride and graphene

    E-Print Network [OSTI]

    Berland, Kristian

    2013-01-01T23:59:59.000Z

    The adsorption of benzene and C60 on graphene and boron nitride (BN) is studied using density functional theory with the non-local correlation functional vdW-DF. By comparing these systems we can systematically investigate their adsorption nature and differences between the two functional versions vdW-DF1 and vdW-DF2. The bigger size of the C60 molecule makes it bind stronger to the surface than benzene, yet the interface between the molecules and the sheets are similar in nature. The binding separation is more sensitive to the exchange variant used in vdW-DF than to the correlation version. This result is related to the exchange and correlation components of the potential energy curve (PEC). We show that a moderate dipole forms for C60 on graphene, unlike for the other adsorption systems. We find that the corrugation is very sensitive to the variant or version of vdW-DF used, in particular the exchange. Further, we show that this sensitivity arise indirectly through the shift in binding separation caused by ...

  6. Assessing electronic structure approaches for gas-ligand interactions in metal-organic frameworks: The CO{sub 2}-benzene complex

    SciTech Connect (OSTI)

    Witte, Jonathon [Department of Chemistry, University of California, Berkeley, California 94720 (United States) [Department of Chemistry, University of California, Berkeley, California 94720 (United States); Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Neaton, Jeffrey B., E-mail: jbneaton@lbl.gov [Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Department of Physics, University of California, Berkeley, California 94720 (United States); Head-Gordon, Martin, E-mail: mhg@cchem.berkeley.edu [Department of Chemistry, University of California, Berkeley, California 94720 (United States) [Department of Chemistry, University of California, Berkeley, California 94720 (United States); Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2014-03-14T23:59:59.000Z

    Adsorption of gas molecules in metal-organic frameworks is governed by many factors, the most dominant of which are the interaction of the gas with open metal sites, and the interaction of the gas with the ligands. Herein, we examine the latter class of interaction in the context of CO{sub 2} binding to benzene. We begin by clarifying the geometry of the CO{sub 2}–benzene complex. We then generate a benchmark binding curve using a coupled-cluster approach with single, double, and perturbative triple excitations [CCSD(T)] at the complete basis set (CBS) limit. Against this ?CCSD(T)/CBS standard, we evaluate a plethora of electronic structure approximations: Hartree-Fock, second-order Møller-Plesset perturbation theory (MP2) with the resolution-of-the-identity approximation, attenuated MP2, and a number of density functionals with and without different empirical and nonempirical van der Waals corrections. We find that finite-basis MP2 significantly overbinds the complex. On the other hand, even the simplest empirical correction to standard density functionals is sufficient to bring the binding energies to well within 1 kJ/mol of the benchmark, corresponding to an error of less than 10%; PBE-D in particular performs well. Methods that explicitly include nonlocal correlation kernels, such as VV10, vdW-DF2, and ?B97X-V, perform with similar accuracy for this system, as do ?B97X and M06-L.

  7. Correlating Extent of Pt–Ni Bond Formation with Low-temperature Hydrogenation of Benzene and 1,3-butadiene over Supported Pt/Ni Bimetallic Catalysts

    SciTech Connect (OSTI)

    Lonergan, W.; Vlachos, D; Chen, J

    2010-01-01T23:59:59.000Z

    Low-temperature hydrogenation of benzene and 1,3-butadiene on supported Pt/Ni catalysts have been used as probe reactions to correlate hydrogenation activity with the extent of Pt-Ni bimetallic bond formation. Pt/Ni bimetallic and Pt and Ni monometallic catalysts were supported on {gamma}-Al{sub 2}O{sub 3} using incipient wetness impregnation. Two sets of bimetallic catalysts were synthesized: one set to study the effect of metal atomic ratio and the other to study the effect of impregnation sequence. Fourier transform infrared spectroscopy (FTIR) CO adsorption studies were performed to characterize the surface composition of the bimetallic nanoparticles, and transmission electron microscopy (TEM) was utilized to characterize the particle size distribution. Batch reactor studies with FTIR demonstrated that all bimetallic catalysts outperformed monometallic catalysts for both benzene and 1,3-butadiene hydrogenation. Within the two sets of bimetallic catalysts, it was found that catalysts with a smaller Pt:Ni ratio possessed higher hydrogenation activity and that catalysts synthesized using co-impregnation had greater activity than sequentially impregnated catalysts. Extended X-ray absorption fine structure (EXAFS) measurements were performed in order to verify the extent of Pt-Ni bimetallic bond formation, which was found to correlate with the hydrogenation activity.

  8. doi: 10.1136/oem.2008.044024 2009 66: 848-853 originally published online SeptemberOccup Environ Med

    E-Print Network [OSTI]

    California at Berkeley, University of

    and occupational exposure to benzene and toluene among exposed workers. The minp test assessed the association, leukaemia and lymphoma among 250 workers exposed to benzene and 140 unexposed controls in a cross regions with altered WBC counts among benzene- exposed workers, after accounting for multiple compar

  9. Synthesis and characterization of d{sup 10} metal complexes with mixed 1,3-di(1H-imidazol-4-yl)benzene and multicarboxylate ligands

    SciTech Connect (OSTI)

    Chen, Zhi-Hao; Zhao, Yue; Chen, Shui-Sheng; Wang, Peng; Sun, Wei-Yin, E-mail: sunwy@nju.edu.cn

    2013-06-15T23:59:59.000Z

    Seven new coordination polymers [Zn(H{sub 2}L)(mbdc)] (1), [Zn(H{sub 3}L)(btc)] (2), [Zn(H{sub 2}L)(Hbtc)] (3), [Zn(H{sub 2}L)(Hbtc)]·H{sub 2}O (4), [Zn{sub 2}(H{sub 2}L)(btc)(?{sub 2}-OH)] (5), [Cd(H{sub 2}L)(mbdc)] (6) and [Cd{sub 3}(H{sub 2}L){sub 2}(btc){sub 2}(H{sub 2}O)]·5H{sub 2}O (7) were synthesized by reactions of the corresponding metal salt with rigid ligand 1,3-di(1H-imidazol-4-yl)benzene (H{sub 2}L) and different carboxylic acids of 1,3-benzenedicarboxylic acid (H{sub 2}mbdc) and benzene-1,3,5-tricarboxylic acid (H{sub 3}btc), respectively. The results of X-ray crystallographic analysis indicate that complex 1 is 1D chain while 2 is a (3,3)-connected 2D network with Point (Schläfli) symbol of (4,8{sup 2}). Complexes 3 and 6 are 2D networks, 4 is a 3-fold interpenetrating 3D framework with Point (Schläfli) symbol of (6{sup 5},8) and 5 is a (3,8)-connected 2D network with Point (Schläfli) symbol of (3,4{sup 2}){sub 2}(3{sup 4},4{sup 6},5{sup 6},6{sup 8},7{sup 3},8), while 7 is a (3,10)-connected 3D net with Schläfli symbol of (3,4,5){sub 2}(3{sup 4},4{sup 8},5{sup 18},6{sup 12},7{sup 2},8). The thermal stability and photoluminescence of the complexes were investigated. Furthermore, DFT calculations were performed for 2–4 to discuss the temperature controlled self-assembly of the complexes. - Graphical abstract: Seven new coordination polymers with multicarboxylate and rigid ditopic 4-imidazole containing ligands have been obtained and found to show different structures and topologies. - Highlights: • Metal complexes with diverse structures of 1D chain, 2D network and 3D framework. • Mixed ligands of 1,3-di(1H-imidazol-4-yl)benzene and multicarboxylate. • Photoluminescence property.

  10. Adsorption and Electronic States of Benzene on Ordered MgO and Al2O3 Thin Films S. C. Street, Q. Guo, C. Xu, and D. W. Goodman*

    E-Print Network [OSTI]

    Goodman, Wayne

    Adsorption and Electronic States of Benzene on Ordered MgO and Al2O3 Thin Films S. C. Street, Q 77843-3255 ReceiVed: June 4, 1996; In Final Form: August 20, 1996X The adsorption and electronic to adsorption of the aromatic ring plane parallel to the surface at low coverages (e1 ML). Intermediate

  11. In-situ air injection, soil vacuum extraction and enhanced biodegradation: A case study in a JP-4 jet fuel contaminated site

    SciTech Connect (OSTI)

    Cho, Jong Soo; DiGiulio, D.C.; Wilson, J.T. [National Risk Management Lab., Ada, OK (United States)

    1997-12-31T23:59:59.000Z

    The US Environmental Protection Agency (US EPA) and the US Coast Guard (USCG) conducted a joint demonstration of in situ remediation of a JP-4 jet fuel spill at the USCG Support Center in Elizabeth City, North Carolina. The jet fuel was trapped beneath a clay layer that extended from the surface to a depth of 1.5 in. The water table was 2.0 in below land surface, and jet fuel extended from a depth of 1.0 to 3.5 in. Air was injected under pressure to depress the water table and bring the entire spill into the unsaturated zone, where hydrocarbons could be removed by volatilization and biodegradation. The injected air was recovered through soil vacuum extraction (SVE) at the treatment area. To document actual removal of hydrocarbons, core samples were acquired in August 1992 before air injection, and September 1994 at the end of the demonstration. The spill originally contained 3600 kg of JP-4. Between the core sampling events, only 55 % of the total petroleum hydrocarbons were removed, but more than 98% of benzene was removed. The initial goal was to reduce the concentration of total petroleum hydrocarbons (TPH) to concentrations less than 100 mg/kg soil. This was not accomplished within 18 months of operation. During the period of operation, ground water was monitored for the concentration of benzene, toluene, ethylbenzene, and the xylene isomers (BTEX), and methyl tertiary butyl ether (MTBE). The concentration of BTEX and MTBE in the subsurface was reduced to a very low level, but concentrations of benzene and MTBE in ground water did not meet the EPA drinking water standards in the most heavily impacted wells. The effluent gas from SVE was monitored for the concentration of total hydrocarbon vapors. 12 refs., 7 figs., 5 tabs.

  12. Benzene analogues of (quasi-)planar M@B{sub n}H{sub n} compounds (M = V{sup ?}, Cr, Mn{sup +}): A theoretical investigation

    SciTech Connect (OSTI)

    Li, Lifen; Xu, Chang; Jin, Baokang; Cheng, Longjiu, E-mail: clj@ustc.edu [Department of Chemistry, Anhui University, Hefei, Anhui 230039 (China)] [Department of Chemistry, Anhui University, Hefei, Anhui 230039 (China)

    2013-11-07T23:59:59.000Z

    The stability of M@B{sub n}H{sub n} (M = V{sup ?}, Cr, Mn{sup +}; n = 5–8) is investigated by density functional theory. For n = 6–8, the isomers possess (quasi-)planar local minima showed by geometry optimization at TPSSh/6-311+G{sup **} level. All the optimized structures are thermodynamics stable according to the large HOMO-LUMO gap, binding energy, vertical ionization potential, and vertical electron affinity analysis. The peripheral and central atomic radius fit each other best at n = 7 confirmed by the variation of the binding energy values. The availability of d atom orbitals in M for participation in the ?-delocalized bonding with the peripheral ring leads to the aromaticity of the (quasi-)planar structures and makes them the benzene analogues. This work establishes firmly the metal-doped borane rings as a new type of aromatic molecule.

  13. Quantum effects and anharmonicity in the H{sub 2}-Li{sup +}-benzene complex: A model for hydrogen storage materials

    SciTech Connect (OSTI)

    Kolmann, Stephen J.; D'Arcy, Jordan H.; Jordan, Meredith J. T., E-mail: m.jordan@chem.usyd.edu.au [School of Chemistry, The University of Sydney, NSW 2006 (Australia)] [School of Chemistry, The University of Sydney, NSW 2006 (Australia)

    2013-12-21T23:59:59.000Z

    Quantum and anharmonic effects are investigated in H{sub 2}-Li{sup +}-benzene, a model for hydrogen adsorption in metal-organic frameworks and carbon-based materials. Three- and 8-dimensional quantum diffusion Monte Carlo (QDMC) and rigid-body diffusion Monte Carlo (RBDMC) simulations are performed on potential energy surfaces interpolated from electronic structure calculations at the M05-2X/6-31+G(d,p) and M05-2X/6-311+G(2df,p) levels of theory using a three-dimensional spline or a modified Shepard interpolation. These calculations investigate the intermolecular interactions in this system, with three- and 8-dimensional 0 K H{sub 2} binding enthalpy estimates, ?H{sub bind} (0 K), being 16.5 kJ mol{sup ?1} and 12.4 kJ mol{sup ?1}, respectively: 0.1 and 0.6 kJ mol{sup ?1} higher than harmonic values. Zero-point energy effects are 35% of the value of ?H{sub bind} (0 K) at M05-2X/6-311+G(2df,p) and cannot be neglected; uncorrected electronic binding energies overestimate ?H{sub bind} (0 K) by at least 6 kJ mol{sup ?1}. Harmonic intermolecular binding enthalpies can be corrected by treating the H{sub 2} “helicopter” and “ferris wheel” rotations as free and hindered rotations, respectively. These simple corrections yield results within 2% of the 8-dimensional anharmonic calculations. Nuclear ground state probability density histograms obtained from the QDMC and RBDMC simulations indicate the H{sub 2} molecule is delocalized above the Li{sup +}-benzene system at 0 K.

  14. Analysis of dissolved benzene plumes and methyl tertiary butyl ether (MTBE) plumes in ground water at leaking underground fuel tank (LUFT) sites

    SciTech Connect (OSTI)

    Happel, A.M.; Rice, D. [Lawrence Livermore National Lab., CA (United States); Beckenbach, E. [California Univ., Berkeley, CA (United States); Savalin, L.; Temko, H.; Rempel, R. [California State Water Resources Control Board, Sacramento, CA (United States); Dooher, B. [California Univ., Los Angeles, CA (United States)

    1996-11-01T23:59:59.000Z

    The 1990 Clean Air Act Amendments mandate the addition of oxygenates to gasoline products to abate air pollution. Currently, many areas of the country utilize oxygenated or reformulated fuel containing 15- percent and I I-percent MTBE by volume, respectively. This increased use of MTBE in gasoline products has resulted in accidental point source releases of MTBE containing gasoline products to ground water. Recent studies have shown MTBE to be frequently detected in samples of shallow ground water from urban areas throughout the United States (Squillace et al., 1995). Knowledge of the subsurface fate and transport of MTBE in ground water at leaking underground fuel tank (LUFT) sites and the spatial extent of MTBE plumes is needed to address these releases. The goal of this research is to utilize data from a large number of LUFT sites to gain insights into the fate, transport, and spatial extent of MTBE plumes. Specific goals include defining the spatial configuration of dissolved MTBE plumes, evaluating plume stability or degradation over time, evaluating the impact of point source releases of MTBE to ground water, and attempting to identify the controlling factors influencing the magnitude and extent of the MTBE plumes. We are examining the relationships between dissolved TPH, BTEX, and MTBE plumes at LUFT sites using parallel approaches of best professional judgment and a computer-aided plume model fitting procedure to determine plume parameters. Here we present our initial results comparing dissolved benzene and MTBE plumes lengths, the statistical significance of these results, and configuration of benzene and MTBE plumes at individual LUFT sites.

  15. Identification and separation of the organic compounds in coal-gasification condensate waters. [5,5 dimethyl hydantoin, dihydroxy benzenes, acetonitrile

    SciTech Connect (OSTI)

    Mohr, D.H. Jr.; King, C.J.

    1983-08-01T23:59:59.000Z

    A substantial fraction of the organic solutes in condensate waters from low-temperature coal-gasification processes are not identified by commonly employed analytical techniques, have low distriution coefficients (K/sub C/) into diisopropyl ether (DIPE) or methyl isobutyl ketone (MIBK), and are resistant to biological oxidation. These compounds represent an important wastewater-treatment problem. Analytical techniques were developed to detect these polar compounds, and the liquid-liquid phase equilibria were measured with several solvents. A high-performance liquid - chromatography (HPLC) technique was employed to analyze four condensate-water samples from a slagging fixed-bed gasifier. A novel sample-preparation technique, consisting of an azeotropic distillation with isopropanol, allowed identification of compounds in the HPLC eluant by combined gas chromatography and mass spectrometry. 5,5-dimethyl hydantoin and related compounds were identified in condensate waters for the first time, and they account for 1 to 6% of the chemical oxygen demand (COD). Dimethyl hydatoin has a K/sub D/ of 2.6 into tributyl phosphate (TBP) and much lower K/sub D/ values into six other solvents. It is also resistant to biological oxidation. Phenols (59 to 76% of the COD), dihydroxy benzenes (0.02 to 9.5% of the COD), and methanol, acetonitrile, and acetone (15% of the COD in one sample) were also detected. Extraction with MIBK removed about 90% of the COD. MIBK has much higher K/sub D/ values than DIPE for dihydroxy benzenes. Chemical reactions occurred during storage of condensate-water samples. The reaction products had low K/sub D/ values into MIBK. About 10% of the COD had a K/sub D/ of nearly zero into MIBK. These compounds were not extracted by MIBK over a wide range of pH. 73 references, 6 figures, 35 tables.

  16. Water on BN doped benzene: A hard test for exchange-correlation functionals and the impact of exact exchange on weak binding

    SciTech Connect (OSTI)

    Al-Hamdani, Yasmine S.; Michaelides, Angelos, E-mail: angelos.michaelides@ucl.ac.uk [Thomas Young Centre and London Centre for Nanotechnology, 17–19 Gordon Street, London WC1H 0AH (United Kingdom); Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom); Alfè, Dario [Thomas Young Centre and London Centre for Nanotechnology, 17–19 Gordon Street, London WC1H 0AH (United Kingdom); Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT (United Kingdom); Lilienfeld, O. Anatole von [Institute of Physical Chemistry, Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel (Switzerland); Argonne National Laboratories, 9700 S. Cass Avenue, Lemont, Illinois 60439 (United States)

    2014-11-14T23:59:59.000Z

    Density functional theory (DFT) studies of weakly interacting complexes have recently focused on the importance of van der Waals dispersion forces, whereas the role of exchange has received far less attention. Here, by exploiting the subtle binding between water and a boron and nitrogen doped benzene derivative (1,2-azaborine) we show how exact exchange can alter the binding conformation within a complex. Benchmark values have been calculated for three orientations of the water monomer on 1,2-azaborine from explicitly correlated quantum chemical methods, and we have also used diffusion quantum Monte Carlo. For a host of popular DFT exchange-correlation functionals we show that the lack of exact exchange leads to the wrong lowest energy orientation of water on 1,2-azaborine. As such, we suggest that a high proportion of exact exchange and the associated improvement in the electronic structure could be needed for the accurate prediction of physisorption sites on doped surfaces and in complex organic molecules. Meanwhile to predict correct absolute interaction energies an accurate description of exchange needs to be augmented by dispersion inclusive functionals, and certain non-local van der Waals functionals (optB88- and optB86b-vdW) perform very well for absolute interaction energies. Through a comparison with water on benzene and borazine (B{sub 3}N{sub 3}H{sub 6}) we show that these results could have implications for the interaction of water with doped graphene surfaces, and suggest a possible way of tuning the interaction energy.

  17. The use of acetylene and 1,3-butadiene as tracers for vehicular combustion in urban air and the estimation of the contributions of vehicular emissions to benzene, and alkane concentrations in the Edmonton industrial area

    SciTech Connect (OSTI)

    Bailey, R. [Environment Canada, Edmonton, Alberta (Canada). Prairie and Northern Region; Wong, R. [Alberta Environmental Protection, Edmonton, Alberta (Canada); Dann, T.; Wang, D. [Environment Canada, Gloucester, Ontario (Canada). Environmental Protection Service

    1998-12-31T23:59:59.000Z

    Acetylene, propylene and 1,3-butadiene concentrations at two downtown urban sites in Alberta, Canada were used to characterize an area dominated by vehicular emissions. The relationship of acetylene with 1,3-butadiene at the Edmonton industrial site was similar to that observed for the two downtown sites. This suggesting that these volatile organic compounds, VOCs, can be used as tracers for vehicular emissions for the Edmonton industrial area. The tracer VOCs were found to correlate with benzene, n-butane, iso-butane, n-pentane, iso-pentane, n-heptane and n-octane concentrations for the two Alberta downtown sites. The best fit lines from the downtown sites were used to predict daily concentrations of benzene and alkanes at the Edmonton industrial site. During the winter, when benzene levels are predicted to reach a maximum of 4.5 to 6.5 m g/m{sup 3}, it is estimated that industrial sources contribute < 1 m g/m{sup 3} to ambient levels at the Edmonton industrial site. During the summer, when predicted benzene levels are at a minimum of 1 to 2 m g/m{sup 3}, industrial area sources dominate the ambient benzene levels at the Edmonton industrial site, and can contribute up to 6 m g/m{sup 3}. For alkanes, such as butane and pentane, industrial area sources or evaporative storage tank emissions dominate throughout the year. This dominance of industrial sources is also observed for n-heptane and n-octane during summer months. During the winter when predicted n-heptane and n-octane concentrations reach a maximum, 11 to 100% of ambient daily levels can be attributed to vehicular emissions.

  18. Adequacy of benzo(a)pyrene and benzene soluble materials as indicators of exposure to polycyclic aromatic hydrocarbons in a Sderberg aluminum smelter

    SciTech Connect (OSTI)

    Friesen, M.C.; Demers, P.A.; Spinelli, J.J.; Le, N.D. [University of British Columbia, Vancouver, BC (Canada). School of Occupational & Environmental Hygiene

    2008-07-01T23:59:59.000Z

    Occupational and environmental exposure to polycyclic aromatic hydrocarbons (PAHs) occurs as a complex mixture that is evaluated using specific components, such as benzo(a)pyrene (BaP) and benzene soluble materials (BSM). Factors that influence the relationship between BaP, BSM, and other PAHs within an aluminum smelter were investigated. Personal samples collected from 1978 to 2001 were used. Differences in the log-transformed ratios (PAH/BaP, BaP/BSM) due to anode paste composition, pot group, season, and job were examined using linear regression. In linear regression, 27% of the variability in the log-transformed BaP/BSM ratio was explained by coal tar pitch, work area, and job; no seasonal or pot group differences were observed. Within the potrooms, BaP was very strongly correlated with other PAHs (majority 0.9). Depending on the PAH, between 23% and 89% of the variability in the log-transformed PAH/BSM was explained by season, coal tar pitch, pot group, and job. The BaP toxic equivalency factors of the mixture varied more across job (2.1-3.5) than across coal tar pitch source (1.8-2.8) or pot group (2.3-2.5). Seasonal and work area differences in the relationship between BaP and other PAHs have not been reported previously.

  19. Supplementary Figure 1. Time trace of background mixing current reveals a 3 noise floor of ~0.12 nA for our proof-of-principle graphene heterodyne

    E-Print Network [OSTI]

    Zhong, Zhaohui

    ) Concentration at minimum injected mass (ppm) Pentane 0 36 - - - Hexane 0 69 - - - Benzene 0 80 - - - Toluene 0 concentration in the GC channel that the graphene sensor is exposed to. The concentration, C, in ppm or ppb

  20. Radical anionic versus neutral 2,2'-bipyridyl coordination in uranium complexes supported by amide and ketimide ligands.

    E-Print Network [OSTI]

    Diaconescu, PL; Cummins, CC

    2015-01-01T23:59:59.000Z

    the organometallic chemistry of uranium. The radical anionicof Chemistry 2012 Journal Name present 2.4(9) at the uraniumChemistry 2013 Since our initial examples, others have also reported bridging benzene or toluene uranium

  1. THE COORDINATION CHEMISTRY OF METAL SURFACES

    E-Print Network [OSTI]

    Muetterties, Earl L.

    2013-01-01T23:59:59.000Z

    of methyl isocyanide, acetonitrile 1 benzene and toluene.desorb from tn1s sur f ace. 11 Acetonitrile forms an orderedNi(.l00) respectively. Acetonitrile thermal desorption from

  2. Activated carbon cleanup of the acid gas feed to Claus sulfur plants

    SciTech Connect (OSTI)

    Harruff, L.G.; Bushkuhl, S.J. [Saudi Aramco, Dhahran (Saudi Arabia)

    1996-12-31T23:59:59.000Z

    This paper presents the details of a recently developed novel process using activated carbon to remove hydrocarbon contaminants from the acid gas feed to Claus sulfur recovery units. Heavy hydrocarbons, particularly benzene, toluene and xylene (BTX) have been linked to coke formation and catalyst deactivation in Claus converters. This deactivation results in reduced sulfur recovery and increased sulfur emissions from these plants. This effect is especially evident in split flow Claus plants which bypass some of the acid gas feed stream around the initial combustion step because of a low hydrogen sulfide concentration. This new clean-up process was proven to be capable of removing 95% of the BTX and other C{sub 6}{sup +} hydrocarbons from acid gas over a wide range of actual plant conditions. Following the adsorption step, the activated carbon was easily regenerated using low pressure steam. A post regeneration drying step using plant fuel gas also proved beneficial. This technology was extensively pilot tested in Saudi Aramco`s facilities in Saudi Arabia. Full scale commercial units are planned for two plants in the near future with the first coming on-line in 1997. The process described here represents the first application of activated carbon in this service, and a patent has been applied for. The paper will discuss the pilot plant results and the issues involved in scale-up to commercial size.

  3. Trip Report-Produced-Water Field Testing

    SciTech Connect (OSTI)

    Sullivan, Enid J. [Los Alamos National Laboratory

    2012-05-25T23:59:59.000Z

    Los Alamos National Laboratory (LANL) conducted field testing of a produced-water pretreatment apparatus with assistance from faculty at the Texas A&M University (TAMU) protein separation sciences laboratory located on the TAMU main campus. The following report details all of the logistics surrounding the testing. The purpose of the test was to use a new, commercially-available filter media housing containing modified zeolite (surfactant-modified zeolite or SMZ) porous medium for use in pretreatment of oil and gas produced water (PW) and frac-flowback waters. The SMZ was tested previously in October, 2010 in a lab-constructed configuration ('old multicolumn system'), and performed well for removal of benzene, toluene, ethylbenzene, and xylenes (BTEX) from PW. However, a less-expensive, modular configuration is needed for field use. A modular system will allow the field operator to add or subtract SMZ filters as needed to accommodate site specific conditions, and to swap out used filters easily in a multi-unit system. This test demonstrated the use of a commercial filter housing with a simple flow modification and packed with SMZ for removing BTEX from a PW source in College Station, Texas. The system will be tested in June 2012 at a field site in Pennsylvania for treating frac-flowback waters. The goals of this test are: (1) to determine sorption efficiency of BTEX in the new configuration; and (2) to observe the range of flow rates, backpressures, and total volume treated at a given flow rate.

  4. Innovative coke oven gas cleaning system for retrofit applications

    SciTech Connect (OSTI)

    Not Available

    1992-08-24T23:59:59.000Z

    The coke plant at the Sparrows Point Plant consist of three coke oven batteries and two coal chemical plants. The by-product coke oven gas (COG) consists primarily of hydrogen, methane, carbon monoxide, nitrogen and contaminants consisting of tars, light oils (benzene, toluene, and xylene) hydrogen sulfide, ammonia, water vapor and other hydrocarbons. This raw coke oven gas needs to be cleaned of most of its contaminants before it can be used as a fuel at other operations at the Sparrows Point Plant. In response to environmental concerns, BSC decided to replace much of the existing coke oven gas treatment facilities in the two coal chemical Plants (A and B) with a group of technologies consisting of: Secondary Cooling of the Coke oven Gas; Hydrogen Sulfide Removal; Ammonia Removal; Deacification of Acid Gases Removed; Ammonia Distillation and Destruction; and, Sulfur Recovery. This combination of technologies will replace the existing ammonia removal system, the final coolers, hydrogen sulfide removal system and the sulfur recovery system. The existing wastewater treatment, tar recovery and one of the three light oil recovery systems will continue to be used to support the new innovative combination of COG treatment technologies.

  5. Innovative coke oven gas cleaning system for retrofit applications. Quarterly environmental monitoring report No. 1, January 1, 1991--June 30, 1991

    SciTech Connect (OSTI)

    Not Available

    1992-08-24T23:59:59.000Z

    The coke plant at the Sparrows Point Plant consist of three coke oven batteries and two coal chemical plants. The by-product coke oven gas (COG) consists primarily of hydrogen, methane, carbon monoxide, nitrogen and contaminants consisting of tars, light oils (benzene, toluene, and xylene) hydrogen sulfide, ammonia, water vapor and other hydrocarbons. This raw coke oven gas needs to be cleaned of most of its contaminants before it can be used as a fuel at other operations at the Sparrows Point Plant. In response to environmental concerns, BSC decided to replace much of the existing coke oven gas treatment facilities in the two coal chemical Plants (A and B) with a group of technologies consisting of: Secondary Cooling of the Coke oven Gas; Hydrogen Sulfide Removal; Ammonia Removal; Deacification of Acid Gases Removed; Ammonia Distillation and Destruction; and, Sulfur Recovery. This combination of technologies will replace the existing ammonia removal system, the final coolers, hydrogen sulfide removal system and the sulfur recovery system. The existing wastewater treatment, tar recovery and one of the three light oil recovery systems will continue to be used to support the new innovative combination of COG treatment technologies.

  6. A Lean Methane Prelixed Laminar Flame Doped witg Components of Diesel Fuel. Part I: n)Butylbenzene

    E-Print Network [OSTI]

    Pousse, Emir; Fournet, René; Battin-Leclerc, Frédérique; 10.1016/j.combustflame.2008.09.012

    2009-01-01T23:59:59.000Z

    To better understand the chemistry involved during the combustion of components of diesel fuel, the structure of a laminar lean premixed methane flame doped with n-butylbenzene has been investigated. The inlet gases contained 7.1% (molar) of methane, 36.8% of oxygen and 0.96% of n-butylbenzene corresponding to an equivalence ratio of 0.74 and a ratio C10H14 / CH4 of 13.5%. The flame has been stabilized on a burner at a pressure of 6.7 kPa using argon as diluent, with a gas velocity at the burner of 49.2 cm/s at 333 K. Quantified species included the usual methane C0-C2 combustion products, but also 16 C3-C5 hydrocarbons, 7 C1-C3 oxygenated compounds, as well as 20 aromatic products, namely benzene, toluene, phenylacetylene, styrene, ethylbenzene, xylenes, allylbenzene, propylbenzene, cumene, methylstyrenes, butenylbenzenes, indene, indane, naphthalene, phenol, benzaldehyde, anisole, benzylalcohol, benzofuran, and isomers of C10H10 (1-methylindene, dihydronaphtalene, butadienylbenzene). A new mechanism for the...

  7. Thermochemical conversion of waste materials to valuable products

    SciTech Connect (OSTI)

    Saraf, S. [Engineering Technologies, Lombard, IL (United States)

    1997-12-31T23:59:59.000Z

    The potential offered by a large variety of solid and liquid wastes for generating value added products is widely recognized. Extensive research and development has focused on developing technologies to recover energy and valuable products from waste materials. These treatment technologies include use of waste materials for direct combustion, upgrading the waste materials into useful fuel such as fuel gas or fuel oil, and conversion of waste materials into higher value products for the chemical industry. Thermal treatment in aerobic (with oxygen) conditions or direct combustion of waste materials in most cases results in generating air pollution and thereby requiring installation of expensive control devices. Thermochemical conversion in aerobic (without oxygen) conditions, referred to as thermal decomposition (destructive distillation) results in formation of usable liquid, solid, and gaseous products. Thermochemical conversion includes gasification, liquefaction, and thermal decomposition (pyrolysis). Each thermochemical conversion process yields a different range of products and this paper will discuss thermal decomposition in detail. This paper will also present results of a case study for recovering value added products, in the form of a liquid, solid, and gas, from thermal decomposition of waste oil and scrap tires. The product has a high concentration of benzene, xylene, and toluene. The solid product has significant amounts of carbon black and can be used as an asphalt modifier for road construction. The gas product is primarily composed of methane and is used for heating the reactor.

  8. Pyrolysis of scrap tires: Can it be profitable?

    SciTech Connect (OSTI)

    Wojtowicz, M.A.; Serio, M.A.

    1996-10-01T23:59:59.000Z

    Pyrolysis--the thermal degradation in the absence of oxygen--is one way to reprocess scrap tires. The products are fuel gas, oils, and a solid residue (char), which contains appreciable quantities of mineral matter and low-grade carbon black. The three products have comparable yields by weight. The two most important factors affecting process economics are the tipping fees charged for tire disposal and the selling prices of the products. Selling prices of the products yield low returns because of the low market value of the fuels and the low quality of the recovered char or carbon black. Therefore, to obtain a positive cash flow, it would be desirable to develop a process based on the recovery of value-added products such as high-grade carbon black, activated carbon, or valuable chemicals (e.g., benzene, toluene, and xylene). The authors believe that significant improvement in the economics can be accomplished by upgrading the primary pyrolysis products to secondary products of higher value.

  9. Superfund Record of Decision (EPA Region 2): FAA (Federal Aviation Administration) Technical Center, Atlantic County, New Jersey (First remedial action), September 1989

    SciTech Connect (OSTI)

    Not Available

    1989-09-26T23:59:59.000Z

    The 5,000-acre multipurpose FAA Technical Center site is a Federal Facility eight miles northwest of Atlantic City, in Atlantic County, New Jersey. Atlantic City's municipal water supply is provided by nine ground-water supply wells located just north of the reservoir on FAA property as well as by water drawn directly from the reservoir. Land use in the site vicinity includes forested land and commercial and residential areas. There are 25 known areas of contamination at the FAA Technical Center. Further areas of contamination will be addressed in future Records of Decision. Soil and ground water at the site are contaminated with VOCs apparently attributable to the jet fuel farm. Subsurface jet fuel contamination is probably the result of leaking pipes, storage tanks, and spills associated with above-ground and underground storage tanks, associated valves, piping, and dry wells, or a truck loading stand. As an interim remedial measure, free product recovery pumps were installed in 1988-89 in three onsite wells to recover the hydrocarbon plume floating on the water table. The primary contaminants of concern affecting the soil and ground water are VOCs including benzene, toluene, and xylenes; and other organics including PAHs (naphthalene) and phenols.

  10. High Btu gas from peat. A feasibility study. Part 3. Market analysis. Task 8. Final report

    SciTech Connect (OSTI)

    Not Available

    1982-01-01T23:59:59.000Z

    The primary objective of this task, which was the responsibility of the Minnesota Gas Company, was to identify and characterize the market potential for the plant by-products - BTX (mixture of benzene, toluene and xylene), phenol, ammonia, sulfur, and sodium sulfate - and to assign value to them. Although traditionally a growth industry, the chemicals market has been generally weakened by the recession, and is experiencing back to back years of declining production. This is due to bad health of specific end uses, such as fertilizer from ammonia. In the long run, this trend is expected to moderate. It is felt that the proposed peat plant has a favorable position in the markets of each of its by-products. This is due to the synergism with nearby industries which are major consumers of these by-products. In the case of sulfur and ammonia, the Red River agricultural area is a large potential market. For sodium sulfate, phenols and perhaps BTX, the nearby paper and timber products industries are large potential markets. The values for these by-products used in the financial analysis were intentionally conservative. This is because of the uncertainty in the quantity and quality. More tests are needed in an integrated facility in order to determine these factors and the variability of each. This is particularly true of the by-product oils which could vary significantly with operating conditions and may even require alternate processing schemes. 18 references, 9 figures, 14 tables.

  11. Mobile Source Air Toxics (MSATs) from High Efficiency Clean Combustion: Catalytic Exhaust Treatment Effects

    SciTech Connect (OSTI)

    Storey, John Morse [ORNL; Lewis Sr, Samuel Arthur [ORNL; Parks, II, James E [ORNL; Barone, Teresa L [ORNL; Prikhodko, Vitaly Y [ORNL

    2008-01-01T23:59:59.000Z

    High Efficiency Clean Combustion (HECC) strategies such as homogenous charge compression ignition (HCCI) and pre-mixed charge compression ignition (PCCI) offer much promise for the reduction of NOx and PM from diesel engines. While delivering low PM and low NOx, these combustion modes often produce much higher levels of CO and HC than conventional diesel combustion modes. In addition, partially oxygenated species such as formaldehyde (an MSAT) and other aldehydes increase with HECC modes. The higher levels of CO and HCs have the potential to compromise the performance of the catalytic aftertreatment, specifically at low load operating points. As HECC strategies become incorporated into vehicle calibrations, manufacturers need to avoid producing MSATs in higher quantities than found in conventional combustion modes. This paper describes research on two different HECC strategies, HCCI and PCCI. Engine-out data for several MSAT species (formaldehyde, acetaldehyde, benzene, toluene, ethylbenzene, xylenes, naphthalene, PAHs, diesel PM) as well as other HC species are presented and compared when possible with conventional operation. In addition, catalyst-out values were measured to assess the destruction of individual MSATs over the catalyst. At low engine loads, MSATs were higher and catalyst performance was poorer. Particle sizing results identify large differences between PM from conventional and HECC operation.

  12. Operable Unit 1 remedial investigation report, Eielson Air Force Base, Alaska

    SciTech Connect (OSTI)

    Gilmore, T.J.; Fruland, R.M.; Liikala, T.L. [and others

    1994-06-01T23:59:59.000Z

    This remedial investigation report for operable Unit 1 (OU-1) at Eielson Air Force Base presents data, calculations, and conclusions as to the nature and extent of surface and subsurface contamination at the eight source areas that make up OU-1. The information is based on the 1993 field investigation result and previous investigations. This report is the first in a set of three for OU-1. The other reports are the baseline risk assessment and feasibility study. The information in these reports will lead to a Record of Decision that will guide and conclude the environmental restoration effort for OU-1 at Eielson Air Force Base. The primary contaminants of concern include fuels and fuel-related contaminants (diesel; benzene, toluene, ethylbenzene, and xylene; total petroleum hydrocarbon; polycyclic aromatic hydrocarbons), maintenance-related solvents and cleaners (volatile chlorinated hydrocarbons such as trichloroothylene), polychlorinated biphenyls, and dichlorodiphenyltrichloroethane (DDT). The origins of contaminants of concern include leaks from storage tanks, drums and piping, and spills. Ongoing operations and past sitewide practices also contribute to contaminants of concern at OU-1 source areas. These include spraying mixed oil and solvent wastes on unpaved roads and aerial spraying of DDT.

  13. Superfund Record of Decision (EPA Region 3): Kane and Lombard Site, Baltimore, Maryland (first remedial action), September 1987. Final report

    SciTech Connect (OSTI)

    Not Available

    1987-09-30T23:59:59.000Z

    The Kane and Lombard site is an 8.4-acre parcel of undeveloped land in Baltimore, Maryland. Dumping and burning of construction debris, domestic trash, and drums occurred at the site from 1962 until 1967 when the city passed an ordinance prohibiting the open burning of refuse. Illegal dumping continued from 1967 until approximately 1984, during which time many citations were issued for illegal burning on the property. In 1980, Maryland State inspectors observed between 400 and 500 drums, the majority of which were rusted, damaged and contained holes. Following an onsite property assessment, EPA authorized the immediate removal of 1,163 drums in 1984. Of those, 822 drums were classified as empty and 341 drums contained contaminants which included: benzene, toluene, xylene, PAHs, PCBs, and heavy metals. Approximately six inches of soil below the drums were removed and disposed offsite. The site was stabilized by regrading, capping and revegetation. Currently, soil and ground water are contaminated with these prior drum contaminants.

  14. Ambient concentrations, sources, emission rates, and photochemical reactivity of C{sub 2}-C{sub 10} hydrocarbons in Porto Alegre, Brazil

    SciTech Connect (OSTI)

    Grosjean, E.; Grosjean, D. [DGA, Inc., Ventura, CA (United States)] [DGA, Inc., Ventura, CA (United States); Rasmussen, R.A. [Oregon Graduate Inst. of Science and Technology, Portland, OR (United States). Dept. of Environmental Science and Engineering] [Oregon Graduate Inst. of Science and Technology, Portland, OR (United States). Dept. of Environmental Science and Engineering

    1998-07-15T23:59:59.000Z

    The combination of vehicle fuels used in Porto Alegre, Brazil, is unique in the world. As a result, air pollution control strategies for Porto Alegre, where vehicles account for ca. 99% and ca. 86% of total city wide CO and hydrocarbons emissions, respectively, must make use of air quality data specific to the Porto Alegre area. In this study, ambient concentrations of 66 C{sub 2}-C{sub 10} hydrocarbons have been measured for ca. 1 year (March 1996--April 1997) at downtown Porto Alegre locations. On the average, the 10 most abundant hydrocarbons on a mass concentration basis were, in decreasing order, as follows: acetylene, ethylene, propane, toluene, isopentane, (m+p)-xylene, propene, n-butane, benzene, and n-pentane. Scatterplots of ambient concentrations showed a high degree of correlation among hydrocarbon classes (e.g., alkenes, isobutene vs 1-pentene), between hydrocarbons (alkanes, alkenes, and aromatics) and acetylene, and between hydrocarbons and carbon monoxide. Mid-1996 hydrocarbon emissions rates (e.g., 3,274 {+-} 828 and 1,418 {+-} 369 t per year for acetylene and isopentane, respectively) are estimated from regression analysis of ambient hydrocarbon vs ambient CO. Reactivity rankings are presented, one involving reaction with OH (using hydrocarbon-OH reaction rate constants) and the other involving the production of ozone (using maximum incremental reactivity coefficients).

  15. A case report of motor neuron disease in a patient showing significant level of DDTs, HCHs and organophosphate metabolites in hair as well as levels of hexane and toluene in blood

    SciTech Connect (OSTI)

    Kanavouras, Konstantinos [Department of Neurology, Medical School, University of Crete, Heraklion, Crete (Greece)] [Department of Neurology, Medical School, University of Crete, Heraklion, Crete (Greece); Tzatzarakis, Manolis N. [Center of Toxicology Science and Research, University of Crete, Heraklion, Crete (Greece)] [Center of Toxicology Science and Research, University of Crete, Heraklion, Crete (Greece); Mastorodemos, Vasileios; Plaitakis, Andreas [Department of Neurology, Medical School, University of Crete, Heraklion, Crete (Greece)] [Department of Neurology, Medical School, University of Crete, Heraklion, Crete (Greece); Tsatsakis, Aristidis M., E-mail: aris@med.uoc.gr [Center of Toxicology Science and Research, University of Crete, Heraklion, Crete (Greece)

    2011-11-15T23:59:59.000Z

    Motor neuron disease is a devastating neurodegenerative condition, with the majority of sporadic, non-familial cases being of unknown etiology. Several epidemiological studies have suggested that occupational exposure to chemicals may be associated with disease pathogenesis. We report the case of a patient developing progressive motor neuron disease, who was chronically exposed to pesticides and organic solvents. The patient presented with leg spasticity and developed gradually clinical signs suggestive of amyotrophic lateral sclerosis, which was supported by the neurophysiologic and radiological findings. Our report is an evidence based case of combined exposure to organochlorine (DDTs), organophosphate pesticides (OPs) and organic solvents as confirmed by laboratory analysis in samples of blood and hair confirming systematic exposure. The concentration of non-specific dialkylphosphates metabolites (DAPs) of OPs in hair (dimethyphopshate (DMP) 1289.4 pg/mg and diethylphosphate (DEP) 709.4 pg/mg) and of DDTs (opDDE 484.0 pg/mg, ppDDE 526.6 pg/mg, opDDD 448.4 pg/mg, ppDDD + opDDT 259.9 pg/mg and ppDDT 573.7 pg/mg) were considerably significant. Toluene and n-hexane were also detected in blood on admission at hospital and quantified (1.23 and 0.87 {mu}g/l, respectively), while 3 months after hospitalization blood testing was found negative for toluene and n-hexane and hair analysis was provided decrease levels of HCHs, DDTs and DAPs. -- Highlights: Black-Right-Pointing-Pointer Exposure to pesticides and organic solvents might be a risk factor for sporadic MND. Black-Right-Pointing-Pointer We report a patient who developed progressive upper and lower motor neuron disease. Black-Right-Pointing-Pointer The patient had a history of occupational exposure to pesticides and solvents. Black-Right-Pointing-Pointer High DDTs' levels and increased levels of DMP and DEP were measured in his hair. Black-Right-Pointing-Pointer The patients' exposure to chemicals might have played a role in MND development.

  16. Process for the production of ethylene and other hydrocarbons from coal

    DOE Patents [OSTI]

    Steinberg, M.; Fallon, P.

    1984-02-15T23:59:59.000Z

    The subject invention comprises the steps of first reacting particulate coal with methane at a temperature in the approximate range of 500/sup 0/C to 1100/sup 0/C and at a partial pressure of methane of less than about 200 psig for a period of less than 10 seconds. More preferably, the method of the subject invention is carried out at a temperature of approximately 850/sup 0/C to 1000/sup 0/C and a pressure of 50 psig for a period of approximately 1.5 seconds. Surprisingly, it has been found that in the practice of the subject invention not only are commercially significant quantities of ethylene produced, namely yields in excess of 10% (percent carbon converted to product), along with economically significant quantities of-benzene and light oils, namely toluene and xylene, but also that there is little, if any, net consumption of methane in the reaction and possibly even a small net production. Since it is apparent that the carbonaceous solids or char remaining after the reaction is carried out may be burned to provide the necessary energy to carry out the process of the subject invention, it is apparent that the subject invention advantageously provides a method for the conversion of coal to economically significant quantities of ethylene, benzene and light oils while requiring only coal and, possibly, small amounts of make-up methane. Other objects and advantages of the subject invention will be apparent to those skilled in the art from a consideration of the attached drawings, the detailed description of the invention, and the experimental examples set forth below.

  17. Functionalization/passivation of porous graphitic carbon with di-tert-amylperoxide

    SciTech Connect (OSTI)

    Jensen, David S.; Gupta, Vipul; Olsen, Rebecca E.; Miller, Alex T.; Davis, Robert C.; Ess, Daniel; Zhu, Zihua; Vail, Michael A.; Dadson, Andrew; Linford, Matthew R.

    2011-11-18T23:59:59.000Z

    Porous graphitic carbon (PGC) particles were functionalized/passivated in situ in packed beds at elevated temperature with neat di-tert-amylperoxide (DTAP) in a column oven. The performance of these particles for high performance liquid chromatography (HPLC) was assayed before and after this chemistry with the following analytes: benzene, toluene, ethyl benzene, n-propyl benzene, n-butyl benzene, p-xylene, phenol, 4-methylphenol, phenetole, 3,5-xylenol, and anisole. After the first functionalization/passivation, the retention factors, k, of these compounds decreased by about 5% and the number of theoretical plates (N) increased by ca. 15%. These values of k then remained roughly constant after a second functionalization/ passivation but a further increase in N was noticed. In addition, after each of the reactions, the peak asymmetries decreased by ca. 15%, for a total of ca. 30%. The columns were then subjected twice to methanol at 100 C for 5 h at 1 mL/min. After these stability tests, the values of k remained roughly constant, the number of plates increased, which is favorable, and the asymmetries rose and then declined, where they remained below the initial values for the unfunctionalized columns. Functionalized and unfunctionalized particles were characterized by scanning electron microscopy and BET measurements, which showed no difference between the functionalized and unfunctionalized materials, and X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry (ToF-SIMS), where ToF-SIMS suggested some chemical differences between the functionalized and unfunctionalized materials. In particular ToF-SIMS suggested that the expected five-carbon fragments from DTAP exist at higher concentrations on DTAP-functionalized PGC. First principle calculations on model graphitic surfaces suggest that the first addition of a DTAP radical to the surface proceeds in an approximately isothermal or slightly favorable fashion, but that subsequent DTAP additions are then increasingly thermodynamically favorable. Thus, this analysis suggests that the direct functionalization/passivation of PGC with DTAP is plausible. Chemometric analyses of the chromatographic and ToF-SIMS data are also presented.

  18. Enthalpies of Vaporization and Vapor Pressures of Some Deuterated Hydrocarbons. Liquid-Vapor Pressure Isotope Effects

    E-Print Network [OSTI]

    Chickos, James S.

    Enthalpies of Vaporization and Vapor Pressures of Some Deuterated Hydrocarbons. Liquid hydrocarbons and their perdeuterated analogues have been determined by correlation-gas chromatography of cyclohexane-d12 and benzene-d6. Other hydrocarbons studied include the perdeuterated forms of hexane, toluene

  19. Environmental Toxicology and Chemistry, Vol. 25, No. 2, pp. 386391, 2006 Printed in the USA

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    . Microcosms simulating contaminated planted soil were exposed to carbon at 20 mg/L/week of mulberry root-free mineral medium to discern the effect of rhizodeposition. Uncontaminated soil controls also were exposed for toluene/benzene/chloro- benzene dioxygenase), bmoA (coding for hydroxylating monooxygenases), and dmp

  20. When benzene's bonds break | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    are infrastructure ready. In the syngas upgrading to hydrocarbon fuels pathway, biomass feedstocks are gasified to produce a syngas, which is used as a feedstock for hydrocarbon...

  1. Treatment of Produced Water Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System

    SciTech Connect (OSTI)

    Lynn E. Katz; Kerry A. Kinney; Robert S. Bowman; Enid J. Sullivan; Soondong Kwon; Elaine B. Darby; Li-Jung Chen; Craig R. Altare

    2006-01-31T23:59:59.000Z

    Co-produced water from the oil and gas industry accounts for a significant waste stream in the United States. Produced waters typically contain a high total dissolved solids content, dissolved organic constituents such as benzene and toluene, an oil and grease component as well as chemicals added during the oil-production process. It has been estimated that a total of 14 billion barrels of produced water were generated in 2002 from onshore operations (Veil, 2004). Although much of this produced water is disposed via reinjection, environmental and cost considerations can make surface discharge of this water a more practical means of disposal. In addition, reinjection is not always a feasible option because of geographic, economic, or regulatory considerations. In these situations, it may be desirable, and often necessary from a regulatory viewpoint, to treat produced water before discharge. It may also be feasible to treat waters that slightly exceed regulatory limits for re-use in arid or drought-prone areas, rather than losing them to reinjection. A previous project conducted under DOE Contract DE-AC26-99BC15221 demonstrated that surfactant modified zeolite (SMZ) represents a potential treatment technology for produced water containing BTEX. Laboratory and field experiments suggest that: (1) sorption of benzene, toluene, ethylbenzene and xylenes (BTEX) to SMZ follows linear isotherms in which sorption increases with increasing solute hydrophobicity; (2) the presence of high salt concentrations substantially increases the capacity of the SMZ for BTEX; (3) competitive sorption among the BTEX compounds is negligible; and, (4) complete recovery of the SMZ sorption capacity for BTEX can be achieved by air sparging the SMZ. This report summarizes research for a follow on project to optimize the regeneration process for multiple sorption/regeneration cycles, and to develop and incorporate a vapor phase bioreactor (VPB) system for treatment of the off-gas generated during air sparging. To this end, we conducted batch and column laboratory SMZ and VPB experiments with synthetic and actual produced waters. Based on the results of the laboratory testing, a pilot scale study was designed and conducted to evaluate the combined SMZ/VPB process. An economic and regulatory feasibility analysis was also completed as part of the current study to assess the viability of the process for various water re-use options.

  2. Demonstrating the efficacy of bioventing using radiotracers

    SciTech Connect (OSTI)

    Baker, R.S. [ENSR Consulting and Engineering, Acton, MA (United States); Ghaemghami, J.; Simkins, S.; Mallory, L.M. [Univ. of Massachusetts, Amherst, MA (United States)

    1994-12-31T23:59:59.000Z

    Direct evidence to support the effectiveness of bioventing was obtained in columns simulating unsaturated zone dynamics. Fine sandy loam from the capillary fringe of a site contaminated with toluene and xylenes was packed into glass columns. Radiolabeled [U-ring-{sup 14}C] toluene and [U-ring-{sup 14}C] m-xylene were separately added to gamma-irradiated control columns and identical nonsterile columns. Toluene (or m-xylene) and CO{sub 2} present in air drawn through the soil were continuously captured in organic vapor and NaOH traps, respectively. The addition of a radiotracer to all columns permitted an accounting of the contaminant mass balance among volatilized, biodegraded, residual, and leached fractions. During two trials involving {sup 14}C-toluene and {sup 14}C-m-xylene, 46 to 57% and 40 to 46%, respectively, of the added {sup 14}C was oxidized to {sup 14}CO{sub 2} in the nonsterile columns, demonstrating that bioremediation had been effective. Volatilization of 75% of added {sup 14}C-toluene and 54% of added {sup 14}C-m-xylene occurred in the sterile controls, whereas the nonsterile columns experienced volatile losses of less than 0.4% and 0.7%, respectively. As virtually no volatile hydrocarbons were detected in the offgas over the course of the bioventing tests from the nonsterile columns, despite the high airflow rate (15 to 20 pore volumes d{sup {minus}1}), offgas treatment may prove unnecessary during bioventing of some field sites.

  3. Is It Homogeneous or Heterogeneous Catalysis Derived from [RhCp*Cl2]2? In Operando-XAFS, Kinetic and Crucial Kinetic Poisoning Evidence for Subnanometer Rh4 Cluster-Based Benzene Hydrogenation Catalysis

    SciTech Connect (OSTI)

    Bayram, Ercan; Linehan, John C.; Fulton, John L.; Roberts, John A.; Szymczak, Nathaniel; Smurthwaite, Tricia D.; Ozkar, Saim; Balasubramanian, Mahalingam; Finke, Richard G.

    2011-11-23T23:59:59.000Z

    Determining the true, kinetically dominant catalytically active species, in the classic benzene hydrogenation system pioneered by Maitlis and co-workers 34 years ago starting with [RhCp*Cl2]2 (Cp* = [{eta}5-C5(CH3)5]), has proven to be one of the most challenging case studies in the quest to distinguish single-metal-based 'homogeneous' from polymetallic, 'heterogeneous' catalysis. The reason, this study will show, is the previous failure to use the proper combination of (i) operando spectroscopy to determine the dominant form(s) of the precatalyst's mass under catalysis (i.e., operating) conditions, plus then and crucially also (ii) the previous lack of the necessary kinetic studies, catalysis being a 'wholly kinetic phenomenon' as J. Halpern long ago noted. An important contribution from this study will be to reveal the power of quantitiative kinetic poisoning experiments for distinguishing single-metal, or in this case subnanometer Rh4 cluster-based catalysis from larger, polymetallic Rh(0)n nanoparticle catalysis, at least under favorable conditions. The combined operando-XAFS (X-ray absorption fine structure) spectroscopy and kinetic evidences provide a compelling case for Rh4-based, with average stoichiometry 'Rh4Cp*2.4Cl4Hc', benzene hydrogenation catalysis in 2-propanol with added Et3N and at 100 C and 50 atm initial H2 pressure. The results also reveal, however, that if even ca. 1.4% of the total soluble Rh(0)n had formed nanoparticles, then those Rh(0)n nanoparticles would have been able to account for all the observed benzene hydrogenation catalytic rate (using commercial, ca. 2 nm, polyethyleneglycol-dodecylether hydrosol stabilized Rh(0)n nanoparticles as a model system). The results 'especially the poisoning methodology developed and employed' are of significant, broader interest since determining the nature of the true catalyst continues to be a central, often vexing issue in any and all catalytic reactions. The results are also of fundamental interest in that they add to a growing body of evidence indicating that certain, appropriately ligated, coordinatively unsaturated, subnanometer M4 transition-metal clusters can be relatively robust catalysts. Also demonstrated herein is that Rh4 clusters are poisoned by Hg(0), demonstrating for the first time that the classic Hg(0) poisoning test of 'homogeneous' vs 'heterogeneous'catalysts cannot distinguish Rh4-based subnanometer catalysts from Rh(0)n nanoparticle catalysts, at least for the present examples of these two specific, Rh-based catalysts.

  4. Method of uranium reclamation from aqueous systems by reactive ion exchange. [US DOE patent application; anion exchange resin of copolymerized divinyl-benzene and styrene having quarternary ammonium groups and bicarbonate ligands

    DOE Patents [OSTI]

    Maya, L.

    1981-11-05T23:59:59.000Z

    A reactive ion exchange method for separation and recovery of values of uranium, neptunium, plutonium, or americium from substantially neutral aqueous systems of said metals comprises contacting said system with an effective amount of a basic anion exchange resin of copolymerized divinyl-benzene and styrene having quarternary ammonium groups and bicarbonate ligands to achieve nearly 100% sorption of said actinyl ion onto said resin and an aqueous system practically free of said actinyl ions. The method is operational over an extensive range of concentrations from about 10/sup -6/ M to 1.0 M actinyl ion and a pH range of about 4 to 7. The method has particulr application to treatment of waste streams from Purex-type nuclear fuel reprocessing facilities and hydrometallurgical processes involving U, Np, P, or Am.

  5. Distribution, Magnitudes, Reactivities, Ratios and Diurnal Patterns of Volatile Organic Compounds in the Valley of Mexico During the MCMA 2002 & 2003 Field Campaigns

    SciTech Connect (OSTI)

    Velasco, E.; Lamb, Brian K.; Westberg, Halvor; Allwine, Eugene J.; Sosa, G.; Arriaga-Colina, J. L.; Jobson, B. T.; Alexander, M. Lizabeth; Prazeller, Peter; Knighton, Walter B.; Rogers, T.; Grutter, M.; Herndon, S.; Kolb, C. E.; Zavala, Mary A.; de Foy, B.; Volkamer, Rainer M.; Molina, Luisa; Molina, Mario J.

    2007-01-23T23:59:59.000Z

    A wide array of volatile organic compound (VOC) measurements was conducted in the Valley of Mexico during the MCMA-2002 and 2003 field campaigns. Study sites included locations in the urban core, in a heavily industrial area and at boundary sites in rural landscapes. In addition, a novel mobile-laboratory-based conditional sampling method was used to collect samples dominated by fresh on-road vehicle exhaust to identify those VOCs whose ambient concentrations were primarily due to vehicle emissions. Four distinct analytical techniques were used: whole air canister samples with Gas Chromatography/Flame Ionization Detection (GC-FID), on-line chemical ionization using a Proton Transfer Reaction Mass Spectrometer (PTR-MS), continuous real-time detection of olefins using a Fast Olefin Sensor (FOS), and long path measurements using UV Differential Optical Absorption Spectrometers (DOAS). The simultaneous use of these techniques provided a wide range of individual VOC measurements with different spatial and temporal scales. The VOC data were analyzed to understand concentration and spatial distributions, diurnal patterns, origin and reactivity in the atmosphere of Mexico City. The VOC burden (in ppbC) was dominated by alkanes (60%), followed by aromatics (15%) and olefins (5%). The remaining 20% was a mix of alkynes, halogenated hydrocarbons, oxygenated species (esters, ethers, etc.) and other unidentified VOCs. However, in terms of ozone production, olefins were the most relevant hydrocarbons. Elevated levels of toxic hydrocarbons, such as 1, 3-butadiene, benzene, toluene and xylenes, were also observed. Results from these various analytical techniques showed that vehicle exhaust is the main source of VOCs in Mexico City and that diurnal patterns depend on vehicular traffic in addition to meteorological processes. Finally, examination of the VOC data in terms of lumped modeling VOC classes and its comparison to the VOC lumped emissions reported in other photochemical air quality modeling studies suggests that some alkanes are underestimated in the emissions inventory, while some olefins and aromatics are overestimated.

  6. Metagenomics, metatranscriptomics and single cell genomics reveal functional response of active Oceanospirillales to Gulf oil spill

    SciTech Connect (OSTI)

    Mason, Olivia U.; Hazen, Terry C.; Borglin, Sharon; Chain, Patrick S. G.; Dubinsky, Eric A.; Fortney, Julian L.; Han, James; Holman, Hoi-Ying N.; Hultman, Jenni; Lamendella, Regina; Mackelprang, Rachel; Malfatti, Stephanie; Tom, Lauren M.; Tringe, Susannah G.; Woyke, Tanja; Zhou, Jizhong; Rubin, Edward M.; Jansson, Janet K.

    2012-06-12T23:59:59.000Z

    The Deepwater Horizon oil spill in the Gulf of Mexico resulted in a deep-sea hydrocarbon plume that caused a shift in the indigenous microbial community composition with unknown ecological consequences. Early in the spill history, a bloom of uncultured, thus uncharacterized, members of the Oceanospirillales was previously detected, but their role in oil disposition was unknown. Here our aim was to determine the functional role of the Oceanospirillales and other active members of the indigenous microbial community using deep sequencing of community DNA and RNA, as well as single-cell genomics. Shotgun metagenomic and metatranscriptomic sequencing revealed that genes for motility, chemotaxis and aliphatic hydrocarbon degradation were significantly enriched and expressed in the hydrocarbon plume samples compared with uncontaminated seawater collected from plume depth. In contrast, although genes coding for degradation of more recalcitrant compounds, such as benzene, toluene, ethylbenzene, total xylenes and polycyclic aromatic hydrocarbons, were identified in the metagenomes, they were expressed at low levels, or not at all based on analysis of the metatranscriptomes. Isolation and sequencing of two Oceanospirillales single cells revealed that both cells possessed genes coding for n-alkane and cycloalkane degradation. Specifically, the near-complete pathway for cyclohexane oxidation in the Oceanospirillales single cells was elucidated and supported by both metagenome and metatranscriptome data. The draft genome also included genes for chemotaxis, motility and nutrient acquisition strategies that were also identified in the metagenomes and metatranscriptomes. These data point towards a rapid response of members of the Oceanospirillales to aliphatic hydrocarbons in the deep sea.

  7. Whole-genorne analysis of the methyl tert-butyl ether-degrading beta-proteobacterium Methylibium petroleiphilum PM1

    SciTech Connect (OSTI)

    Kane, Staci R. [Lawrence Livermore National Laboratory (LLNL); Chakicherla, Anu Y. [Lawrence Livermore National Laboratory (LLNL); Chain, Patrick S. G. [Lawrence Livermore National Laboratory (LLNL); Schmidt, Radomir [University of California, Davis; Shin, M [U.S. Department of Energy, Joint Genome Institute; Legler, Tina C. [Lawrence Livermore National Laboratory (LLNL); Scow, Kate M. [University of California, Davis; Larimer, Frank W [ORNL; Lucas, Susan [Joint Genome Institute, Walnut Creek, California; Richardson, P M [U.S. Department of Energy, Joint Genome Institute; Hristova, Krassimira R. [University of California, Davis

    2007-03-01T23:59:59.000Z

    Methylibium petroleiphilum PM1 is a methylotroph distinguished by its ability to completely metabolize the fuel oxygenate methyl tert-butyl ether (MTBE). Strain PM1 also degrades aromatic (benzene, toluene, and xylene) and straight-chain (C, to C,,) hydrocarbons present in petroleum products. Whole-genome analysis of PM1 revealed an similar to 4-Mb circular chromosome and an similar to 600-kb megaplasmid, containing 3,831 and 646 genes, respectively. Aromatic hydrocarbon and alkane degradation, metal resistance, and methylotrophy are encoded on the chromosome. The megaplasmid contains an unusual t-RNA island, numerous insertion sequences, and large repeated elements, including a 40-kb region also present on the chromosome and a 29-kb tandem repeat encoding phosphonate transport and cobalamin biosynthesis. The megaplasmid also codes for alkane degradation and was shown to play an essential role in MTBE degradation through plasmid-curing experiments. Discrepancies between the insertion sequence element distribution patterns, the distributions of best BLASTP hits among major phylogenetic groups, and the G+C contents of the chromosome (69.2%) and plasmid (66%), together with comparative genome hybridization experiments, suggest that the plasmid was recently acquired and apparently carries the genetic information responsible for PM1's ability to degrade MTBE. Comparative genomic hybridization analysis with two PM1-like MTBE-degrading environmental isolates (similar to 99% identical 16S rRNA gene sequences) showed that the plasmid was highly conserved (ca. 99% identical), whereas the chromosomes were too diverse to conduct resequencing analysis. PM1's genome sequence provides a foundation for investigating MTBE biodegradation and exploring the genetic regulation of multiple biodegradation pathways in M. petroleiphilum and other MTBE-degrading beta-proteobacteria.

  8. Microbial Diversity and Bioremediation of aHydrocarbon-Contaminated Aquifer (Vega Baja, Puerto Rico)

    SciTech Connect (OSTI)

    Rodriguez-Martinez, E.M.; Perez, Ernie X.; Schadt, ChristopherW.; Zhou, Jizhong; Massol-Deya, Arturo A.

    2006-09-30T23:59:59.000Z

    Hydrocarbon contamination of groundwater resources hasbecome a major environmental and human health concern in many parts ofthe world. Our objectives were to employ both culture andculture-independent techniques to characterize the dynamics of microbialcommunity structure within a fluidized bed reactor used to bioremediate adiesel-contaminated groundwater in a tropical environment. Under normaloperating conditions, 97 to 99 percent of total hydrocarbons were removedwith only 14 min hydraulic retention time. Over 25 different cultureswere isolated from the treatment unit (96 percent which utilized dieselconstituents as sole carbon source). Approximately 20 percent of theisolates were also capable of complete denitrification to nitrogen gas.Sequence analysis of 16S rDNA demonstrated ample diversity with mostbelonging to the infinity, beta and gamma subdivision of theProteobacteria, Bacilli, and Actinobacteria groups. Moreover, the geneticconstitution of the microbial community was examined at multiple timepoints with a Functional Gene Array (FGA) containing over 12,000 probesfor genes involved in organic degradation and major biogeochemicalcycles. Total community DNA was extracted and amplified using anisothermal phi29 polymerase-based technique, labeled with Cy5 dye, andhybridized to the arrays in 50 percent formimide overnight at 50 degreesC. Cluster analysis revealed comparable profiles over the course oftreatment suggesting the early selection of a very stable microbialcommunity. A total of 270 genes for organic contaminant degradation(including naphthalene, toluene [aerobic and anaerobic], octane,biphenyl, pyrene, xylene, phenanthrene, and benzene); and 333 genesinvolved in metabolic activities (nitrite and nitrous oxide reductases[nirS, nirK, and nosZ], dissimilatory sulfite reductases [dsrAB],potential metal reducing C-type cytochromes, and methane monooxygenase[pmoA]) were repeatedly detected. Genes for degradation of MTBE,nitroaromatics and chlorinated compounds werealso present, indicating abroad catabolic potential of the treatment unit. FGA's demonstrated theearly establishment of a diverse community with concurrent aerobic andanaerobic processes contributing to the bioremediationprocess.

  9. Thermal Decomposition of Radiation-Damaged Polystyrene

    SciTech Connect (OSTI)

    Abrefah, John; Klinger, George S.

    2000-09-26T23:59:59.000Z

    The radiation-damaged polystyrene (given the identification name of 'polycube') was fabricated by mixing high-density polystyrene material ("Dylene Fines # 100") with plutonium and uranium oxides. The polycubes were used in the 1960s for criticality studies during processing of spent nuclear fuel. The polycubes have since been stored for almost 40 years at the Hanford Plutonium Finishing Plant (PFP) after failure of two processes to reclaim the plutonium and uranium oxides from the polystyrene matrix. Thermal decomposition products from this highly cross-linked polystyrene matrix were characterized using Gas Chromatograph/Mass Spectroscopy (GC/MS) system coupled to a horizontal furnace. The decomposition studies were performed in air and helium atmospheres at about 773 K. The volatile and semi-volatile organic products for the radiation-damaged polystyrene were different compared to virgin polystyrene. The differences were in the number of organic species generated and their concentrations. In the inert (i.e., helium) atmosphere, the major volatile organic products identified (in order of decreasing concentrations) were styrene, benzene, toluene, ethylbenzene, xylene, nathphalene, propane, .alpha.-methylbenzene, indene and 1,2,3-trimethylbenzene. But in air, the major volatile organic species identified changed slightly. Concentrations of the organic species in the inert atmosphere were significantly higher than those for the air atmosphere processing. Overall, 38 volatile organic species were identified in the inert atmosphere compared to 49 species in air. Twenty of the 38 species in the inert conditions were also products in the air atmosphere. Twenty-two oxidized organic products were identified during thermal processing in air.

  10. Metabolic analysis of the soil microbe Dechloromonas aromatica str. RCB: indications of a surprisingly complex life-style and cryptic anaerobic pathways for aromatic degradation

    SciTech Connect (OSTI)

    Salinero, Kennan Kellaris; Keller, Keith; Feil, William S.; Feil, Helene; Trong, Stephan; Di Bartolo, Genevieve; Lapidus, Alla

    2008-11-17T23:59:59.000Z

    Initial interest in Dechloromonas aromatica strain RCB arose from its ability to anaerobically degrade benzene. It is also able to reduce perchlorate and oxidize chlorobenzoate, toluene, and xylene, creating interest in using this organism for bioremediation. Little physiological data has been published for this microbe. It is considered to be a free-living organism. The a priori prediction that the D. aromatica genome would contain previously characterized 'central' enzymes involved in anaerobic aromatic degradation proved to be false, suggesting the presence of novel anaerobic aromatic degradation pathways in this species. These missing pathways include the benzyl succinyl synthase (bssABC) genes (responsible for formate addition to toluene) and the central benzoylCoA pathway for monoaromatics. In depth analyses using existing TIGRfam, COG, and InterPro models, and the creation of de novo HMM models, indicate a highly complex lifestyle with a large number of environmental sensors and signaling pathways, including a relatively large number of GGDEF domain signal receptors and multiple quorum sensors. A number of proteins indicate interactions with an as yet unknown host, as indicated by the presence of predicted cell host remodeling enzymes, effector enzymes, hemolysin-like proteins, adhesins, NO reductase, and both type III and type VI secretory complexes. Evidence of biofilm formation including a proposed exopolysaccharide complex with the somewhat rare exosortase (epsH), is also present. Annotation described in this paper also reveals evidence for several metabolic pathways that have yet to be observed experimentally, including a sulphur oxidation (soxFCDYZAXB) gene cluster, Calvin cycle enzymes, and nitrogen fixation (including RubisCo, ribulose-phosphate 3-epimerase, and nif gene families, respectively). Analysis of the D. aromatica genome indicates there is much to be learned regarding the metabolic capabilities, and life-style, for this microbial species. Examples of recent gene duplication events in signaling as well as dioxygenase clusters are present, indicating selective gene family expansion as a relatively recent event in D. aromatica's evolutionary history. Gene families that constitute metabolic cycles presumed to create D. aromatica's environmental 'foot-print' indicate a high level of diversification between its predicted capabilities and those of its close relatives, A. aromaticum str EbN1 and Azoarcus BH72.

  11. Infrared identification of the {sigma}-complex of Cl-C{sub 6}H{sub 6} in the reaction of chlorine atom and benzene in solid para-hydrogen

    SciTech Connect (OSTI)

    Bahou, Mohammed; Witek, Henryk [Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan (China); Lee, Yuan-Pern [Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan (China)

    2013-02-21T23:59:59.000Z

    The reaction of a chlorine atom with benzene (C{sub 6}H{sub 6}) is important in organic chemistry, especially in site-selective chlorination reactions, but its product has been a subject of debate for five decades. Previous experimental and theoretical studies provide no concrete conclusion on whether the product is a {pi}- or {sigma}-form of the Cl-C{sub 6}H{sub 6} complex. We took advantage of the diminished cage effect of para-hydrogen (p-H{sub 2}) to produce Cl in situ to react with C{sub 6}H{sub 6} (or C{sub 6}D{sub 6}) upon photolysis of a Cl{sub 2}/C{sub 6}H{sub 6} (or C{sub 6}D{sub 6})/p-H{sub 2} matrix at 3.2 K. The infrared spectrum, showing intense lines at 1430.5, 833.6, 719.8, 617.0, and 577.4 cm{sup -1}, and several weaker ones for Cl-C{sub 6}H{sub 6}, and the deuterium shifts of observed new lines unambiguously indicate that the product is a 6-chlorocyclohexadienyl radical, i.e., the {sigma}-complex of Cl-C{sub 6}H{sub 6}. Observation of the {sigma}-complex rather than the {pi}-complex indicates that the {sigma}-complex is more stable in solid p-H{sub 2} at 3.2 K. The spectral information is crucial for further investigations of the Cl + C{sub 6}H{sub 6} reaction either in the gaseous or solution phase.

  12. UNCORRECTEDPROOF Assessment of anaerobic benzene degradation

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    in the USA that are contaminated with gasoline leaks from underground storage tanks (UST) (USEPA, 2005 to remediate more than 50% of the existing gasoline-contaminated UST sites (USEPA, 2000). However

  13. Density functional theory study of the interaction of vinyl radical, ethyne, and ethene with benzene, aimed to define an affordable computational level to investigate stability trends in large van der Waals complexes

    SciTech Connect (OSTI)

    Maranzana, Andrea, E-mail: andrea.maranzana@unito.it, E-mail: anna.giordana@hotmail.com, E-mail: vincenzo.barone@sns.it, E-mail: mauro.causa@unina.it, E-mail: mipavone@unina.it; Giordana, Anna, E-mail: andrea.maranzana@unito.it, E-mail: anna.giordana@hotmail.com, E-mail: vincenzo.barone@sns.it, E-mail: mauro.causa@unina.it, E-mail: mipavone@unina.it; Indarto, Antonius, E-mail: antonius.indarto@che.itb.ac.id; Tonachini, Glauco, E-mail: glauco.tonachini@unito.it [Dipartimento di Chimica, Università di Torino, Corso Massimo D’Azeglio 48, I-10125 Torino (Italy)] [Dipartimento di Chimica, Università di Torino, Corso Massimo D’Azeglio 48, I-10125 Torino (Italy); Barone, Vincenzo, E-mail: andrea.maranzana@unito.it, E-mail: anna.giordana@hotmail.com, E-mail: vincenzo.barone@sns.it, E-mail: mauro.causa@unina.it, E-mail: mipavone@unina.it [Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126, Pisa (Italy)] [Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126, Pisa (Italy); Causà, Mauro, E-mail: andrea.maranzana@unito.it, E-mail: anna.giordana@hotmail.com, E-mail: vincenzo.barone@sns.it, E-mail: mauro.causa@unina.it, E-mail: mipavone@unina.it [Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Università di Napoli “Federico II,” Via Cintia, 80126 Napoli (Italy)] [Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Università di Napoli “Federico II,” Via Cintia, 80126 Napoli (Italy); Pavone, Michele, E-mail: andrea.maranzana@unito.it, E-mail: anna.giordana@hotmail.com, E-mail: vincenzo.barone@sns.it, E-mail: mauro.causa@unina.it, E-mail: mipavone@unina.it [Dipartimento di Scienze Chimiche, Università di Napoli “Federico II,” Complesso Universitario di Monte Sant’Angelo, Via Cintia, I-80126 Napoli (Italy)] [Dipartimento di Scienze Chimiche, Università di Napoli “Federico II,” Complesso Universitario di Monte Sant’Angelo, Via Cintia, I-80126 Napoli (Italy)

    2013-12-28T23:59:59.000Z

    Our purpose is to identify a computational level sufficiently dependable and affordable to assess trends in the interaction of a variety of radical or closed shell unsaturated hydro-carbons A adsorbed on soot platelet models B. These systems, of environmental interest, would unavoidably have rather large sizes, thus prompting to explore in this paper the performances of relatively low-level computational methods and compare them with higher-level reference results. To this end, the interaction of three complexes between non-polar species, vinyl radical, ethyne, or ethene (A) with benzene (B) is studied, since these species, involved themselves in growth processes of polycyclic aromatic hydrocarbons (PAHs) and soot particles, are small enough to allow high-level reference calculations of the interaction energy ?E{sub AB}. Counterpoise-corrected interaction energies ?E{sub AB} are used at all stages. (1) Density Functional Theory (DFT) unconstrained optimizations of the A?B complexes are carried out, using the B3LYP-D, ?B97X-D, and M06-2X functionals, with six basis sets: 6-31G(d), 6-311 (2d,p), and 6-311++G(3df,3pd); aug-cc-pVDZ and aug-cc-pVTZ; N07T. (2) Then, unconstrained optimizations by Møller-Plesset second order Perturbation Theory (MP2), with each basis set, allow subsequent single point Coupled Cluster Singles Doubles and perturbative estimate of the Triples energy computations with the same basis sets [CCSD(T)//MP2]. (3) Based on an additivity assumption of (i) the estimated MP2 energy at the complete basis set limit [E{sub MP2/CBS}] and (ii) the higher-order correlation energy effects in passing from MP2 to CCSD(T) at the aug-cc-pVTZ basis set, ?E{sub CC-MP}, a CCSD(T)/CBS estimate is obtained and taken as a computational energy reference. At DFT, variations in ?E{sub AB} with basis set are not large for the title molecules, and the three functionals perform rather satisfactorily even with rather small basis sets [6-31G(d) and N07T], exhibiting deviation from the computational reference of less than 1 kcal mol{sup ?1}. The zero-point vibrational energy corrected estimates ?(E{sub AB}+ZPE), obtained with the three functionals and the 6-31G(d) and N07T basis sets, are compared with experimental D{sub 0} measures, when available. In particular, this comparison is finally extended to the naphthalene and coronene dimers and to three ??? associations of different PAHs (R, made by 10, 16, or 24 C atoms) and P (80 C atoms)

  14. August 2010 EPL, 91 (2010) 38001 www.epljournal.org

    E-Print Network [OSTI]

    Sharma, Vivek

    2010-01-01T23:59:59.000Z

    in volatile organic solvents are exposed to moist air. After solvent evaporation is complete on an evaporating polymer solu- tion, exposed to a stream of moist air, and once the solvent evaporation is complete-like, rod-coil, star-shaped) and solvents (chloro- form, toluene, carbon disulfide, dichloromethane, benzene

  15. AMERICAN JOURNAL OF INDUSTRIAL MEDICINE 29:236-246 (1 996) Hematotoxocity Among Chinese Workers

    E-Print Network [OSTI]

    California at Berkeley, University of

    Heavily Exposed to Benzene Nathaniel Rothman, MD, MPH, MHS, Gui-Lin Li, MD, Mustafa Dosemeci, PhD, William to variation in the method of measuring blood cells, exposure to additional compounds such as toluene [Andrews. As part of a large cohort study of cancer and hemato- toxicity among approximately 75,000 workers exposed

  16. SERS of molecules that do not adsorb on Ag surfaces: a metalorganic framework-based

    E-Print Network [OSTI]

    previously been shown to enhance Raman signals of surface adsorbates by a factor of 107 . Upon exposing the MOF-coated FON to benzene, toluene, nitrobenzene, or 2,6-di-tert-butylpyridine, the MOF film traps nanocrystals exposed at grain boundaries. This represents a generalized approach for confining aromatic

  17. R. D. Bennett, 2006 Safety Topic Personal Protective

    E-Print Network [OSTI]

    Cohen, Robert E.

    (MEK), nitrobenzene, benzene, toluene, styrene, or THF) ­ For high levels of contamination and glove resistant suit may be appropriate ­ Be aware of loose clothing which could inadvertently be exposed Protective Equipment · Hearing protection ­ People exposed to time weighted average of 85 dbA threshold

  18. Stereoselective Synthesis of the ABC Ring System of Norzoanthamine

    E-Print Network [OSTI]

    Theodorakis, Emmanuel

    commercial quality and used without further purification except where noted. Air- and moisture2Cl2), toluene (PhCH3) and benzene (PhH) were purified by passage through a bed of activated alumina) carried out on 0.25 mm E. Merck silica gel plates (60F-254) using UV light as the visualizing agent and 10

  19. Supporting Information Table of Contents

    E-Print Network [OSTI]

    Theodorakis, Emmanuel

    without further purification except where noted. Air- and moisture- sensitive liquids and solutions were), dichloromethane (DCM), toluene (PhCH3) and benzene (PhH) were purified by passage through a bed of activated) carried out on 0.25 mm E. Merck silica gel plates (60F-254) and visualized under UV light and/or developed

  20. Total Synthesis of Norcembrenolide B and Scabrolide D Alec Saitman, Pauline Rulliere, Steven D. E. Sullivan and Emmanuel A.

    E-Print Network [OSTI]

    Theodorakis, Emmanuel

    ) at highest commercial quality and used without further purification except where noted. Air- and moisture), dichloromethane (CH2Cl2), toluene (PhCH3) and benzene (PhH) were purified by passage through a bed of activated-layer chromatography (TLC) carried out on 0.25 mm E. Merck silica gel plates (60F-254) using UV light

  1. A Strategy Toward the Synthesis of C13-Oxidized

    E-Print Network [OSTI]

    Theodorakis, Emmanuel

    and used without further purification except where noted. Air- and moisture- sensitive liquids), toluene (PhCH3) and benzene (PhH) were purified by passage through a bed of activated alumina.1) carried out on 0.25 mm E. Merck silica gel plates (60F-254) using UV light as the visualizing agent and 10

  2. Regioselective Synthesis of the Tricyclic Core of Lateriflorone

    E-Print Network [OSTI]

    Theodorakis, Emmanuel

    , Acros) at highest commercial quality and used without further purification except where noted. Air), dichloromethane (CH2Cl2), toluene (PhCH3) and benzene (PhH) were purified by passage through a bed of activated) carried out on 0.25 mm E. Merck silica gel plates (60F-254) using UV light as the visualizing agent and 10

  3. Synthetic Studies on Borrelidin: Enantioselective Synthesis of the C1-C12 Fragment.

    E-Print Network [OSTI]

    Theodorakis, Emmanuel

    ) at highest commercial quality and used without further purification except where noted. Air- and moisture), dichloromethane (CH2Cl2), toluene (PhCH3) and benzene (PhH) were purified by passage through a bed of activated by thin-layer chromatography (TLC) carried out on 0.25 mm E. Merck silica gel plates (60F-254) using UV

  4. Introduction The use of ethanol as a gasoline additive is likely to

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    Introduction The use of ethanol as a gasoline additive is likely to increase in the near future will also lead to additional ethanol use. There- fore, it is important to understand how ethanol affects that the presence of ethanol could have undesirable effects on the biodegradation of BTEX (i.e., benzene, toluene

  5. Rana Novini ATOC 3500 Open-air pits are used to burn garbage and other wastes at bases in Iraq and Afghanistan that lack

    E-Print Network [OSTI]

    Toohey, Darin W.

    found in the study: Acetone, Acrolein**, Benzene, Carbon Disulfide, Chlorodifluoromethane, Chloromethane, Toluene Acrolein and Hexachlorobutadiene were occasionally detected far above the MEG ratio--over 1800 percent above the MEG for Acrolein and over 500 percent above the MEG for Hexachlorobutadiene. Plaintiffs

  6. NGWA.org Ground Water Monitoring & Remediation 31, no. 3/ Summer 2011/pages 4754 47 2011, The Author(s)

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    contaminated with fuel ethanol blends. Introduction Ethanol is increasingly being used as a blending agent of an Ethanol Blend by Jie Ma, Zongming Xiu, Amy L. Monier, Irina Mamonkina, Yi Zhang, Yongzhi He, Brent P release of 10% v:v ethanol solution in water mixed with benzene and toluene (50 mg/L each

  7. Cey. J. Sci. (Bio. Sci.) 35 (1): 25-39, 2006 PHYTOREMEDIATION: AN AFFORDABLE GREEN TECHNOLOGY FOR THE

    E-Print Network [OSTI]

    Rajakaruna, Nishanta

    for remediating contaminated bodies of soils and water in developing countries like Sri Lanka, where clean-up can such as trichloroethylene (TCE), a common ground-water pollutant (Newman et al., 1997), herbicides such as atrazine (Burken, gasoline, benzene, toluene, and polycyclic aromatic hydrocarbons (PAHs) (Schnoor et al., 1995, Aprill

  8. ARTICLE IN PRESS S0019-1035(05)00115-6/FLA AID:7629 Vol.() [DTD5] P.1 (1-10)

    E-Print Network [OSTI]

    Ferris, James P.

    of products were determined. Photolysis of ethylene yields mainly saturated compounds (ethane, propane, and butane) while photolysis of acetylene yields the same saturated compounds as well as ethylene with much smaller amounts of aromatic compounds like benzene, toluene and phenylacetylene. The reaction

  9. Naphthalene and o-Xylene Adsorption onto High Carbon Fly Ash

    E-Print Network [OSTI]

    Aydilek, Ahmet

    electricity, resulting in the generation of vast quantities of coal combustion by-products. One of these by for the treatment of groundwater con- taining both organic and inorganic pollutants (Guerin et al. 2002; Jenk et al. 2003; Long et al. 2008). Approximately 90% of the coal used in the United States is burned to produce

  10. Optimal synthesis of p-xylene separation processes based on crystallization technology

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    that arises in hybrid designs where the first step is commonly performed by adsorption. A novel superstructure) adsorption, or (3) a hybrid crystallization/adsorption process.1 Distillation is not a competitive technology) resulting in columns with high reflux ratios and a large number of trays. Table 1 Adsorption

  11. altering toluene 4-monooxygenase: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in chronic human spinal cord injury Katherine M. Deutscha, b, T. George Hornbya, c, Brian D joint torques at the ankle, knee and hip. The results showed that SCI individuals...

  12. anaerobic toluene mineralization: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and found in nature as the mineral tincal. Boric acid, also known as orthoboric acid boric acid. The most common minerals of commercial importance in the United States were...

  13. Development of a Hydrogasification Process for Co-Production of Substitute Natural Gas (SNG) and Electric Power from Western Coals

    SciTech Connect (OSTI)

    Sun, Xiaolei; Rink, Nancy

    2011-04-30T23:59:59.000Z

    This report presents the results of the research and development conducted on an Advanced Hydrogasification Process (AHP) conceived and developed by Arizona Public Service Company (APS) under U.S. Department of Energy (DOE) contract: DE-FC26-06NT42759 for Substitute Natural Gas (SNG) production from western coal. A double-wall (i.e., a hydrogasification contained within a pressure shell) down-flow hydrogasification reactor was designed, engineered, constructed, commissioned and operated by APS, Phoenix, AZ. The reactor is ASME-certified under Section VIII with a rating of 1150 pounds per square inch gage (psig) maximum allowable working pressure at 1950 degrees Fahrenheit ({degrees}F). The reaction zone had a 1.75 inch inner diameter and 13 feet length. The initial testing of a sub-bituminous coal demonstrated ~ 50% carbon conversion and ~10% methane yield in the product gas under 1625{degrees}F, 1000 psig pressure, with a 11 seconds (s) residence time, and 0.4 hydrogen-to-coal mass ratio. Liquid by-products mainly contained Benzene, Toluene, Xylene (BTX) and tar. Char collected from the bottom of the reactor had 9000-British thermal units per pound (Btu/lb) heating value. A three-dimensional (3D) computational fluid dynamic model simulation of the hydrodynamics around the reactor head was utilized to design the nozzles for injecting the hydrogen into the gasifier to optimize gas-solid mixing to achieve improved carbon conversion. The report also presents the evaluation of using algae for carbon dioxide (CO{sub 2}) management and biofuel production. Nannochloropsis, Selenastrum and Scenedesmus were determined to be the best algae strains for the project purpose and were studied in an outdoor system which included a 6-meter (6M) radius cultivator with a total surface area of 113 square meters (m{sup 2}) and a total culture volume between 10,000 to 15,000 liters (L); a CO{sub 2} on-demand feeding system; an on-line data collection system for temperature, pH, Photosynthetically Activate Radiation (PAR) and dissolved oxygen (DO); and a ~2 gallons per minute (gpm) algae culture dewatering system. Among the three algae strains, Scenedesmus showed the most tolerance to temperature and irradiance conditions in Phoenix and the best self-settling characteristics. Experimental findings and operational strategies determined through these tests guided the operation of the algae cultivation system for the scale-up study. Effect of power plant flue gas, especially heavy metals, on algae growth and biomass adsorption were evaluated as well.

  14. Corrective Action Investigation Plan for Corrective Action Unit 405: Area 3 Septic Systems, Tonopah Test Range, Nevada(April 2001, Rev. 0) with Record of Technical Change No. 1

    SciTech Connect (OSTI)

    DOE /NV

    2001-04-26T23:59:59.000Z

    This Corrective Action Investigation Plan contains the U.S. Department of Energy, Nevada Operations Office's (DOE/NV's) approach to collect the data necessary to evaluate corrective action alternatives appropriate for the closure of Corrective Action Unit (CAU) 405, Area 3 Septic Systems, Tonopah Test Range (TTR), under the Federal Facility Agreement and Consent Order. Corrective Action Unit 405 consists of Corrective Action Sites 03-05-002-SW03, 03-05-002-SW04, and 03-05-002-SW07 (also collectively known as: Septic Waste Systems [SWSs] 3, 4, and 7). Located in Area 3 in the northwest section of the TTR, approximately 140 miles northwest of Las Vegas, this location was historically (between 1960 and 1990) used as a research facility with the mission to perform defense-related projects, and whose operations generated sanitary and industrial wastewaters potentially contaminated with COPCs and disposed of in septic tanks and leachfields. Though Septic Waste Systems 3, 4, and 7 were origin ally constructed to receive sanitary sewage, they may have inadvertently received effluent containing potentially hazardous and radiological constituents containing acetone, benzene, ethylbenzene, 4-methyl-2-pentanone, toluene, xylenes, volatile organic compound constituents, phenols, arsenic, barium, lead, mercury, hydrocarbons of oil and grease, and uranium-234, -235, and -238. The Area 3 septic systems were documented in a DOE/NV 1996 report as being included in the septic tank abandonment program conducted by Sandia National Laboratories in 1993; however, this program was not completed and the possibility exists that some of the Area 3 septic tanks may not have been abandoned. Even though all of the SWSs addressed in this CAIP are inactive, geophysical surveys conducted in 1993 were generally inconclusive and did not provide useful data for the purposes of this investigation. The scope of this current investigation, therefore, will be to determine the existence of the identified CO PCs and excavation will be the primary investigation method employed for these leachfield systems, but this effort may be limited by existing facilities and utilities. The results of this field investigation will support a defensible evaluation of corrective action alternatives in the subsequent corrective action decision document.

  15. Process to recycle shredder residue

    DOE Patents [OSTI]

    Jody, Bassam J. (Chicago, IL); Daniels, Edward J. (Oak Lawn, IL); Bonsignore, Patrick V. (Channahon, IL)

    2001-01-01T23:59:59.000Z

    A system and process for recycling shredder residue, in which separating any polyurethane foam materials are first separated. Then separate a fines fraction of less than about 1/4 inch leaving a plastics-rich fraction. Thereafter, the plastics rich fraction is sequentially contacted with a series of solvents beginning with one or more of hexane or an alcohol to remove automotive fluids; acetone to remove ABS; one or more of EDC, THF or a ketone having a boiling point of not greater than about 125.degree. C. to remove PVC; and one or more of xylene or toluene to remove polypropylene and polyethylene. The solvents are recovered and recycled.

  16. Hoe Creek groundwater restoration, 1989

    SciTech Connect (OSTI)

    Renk, R.R.; Crader, S.E.; Lindblom, S.R.; Covell, J.R.

    1990-01-01T23:59:59.000Z

    During the summer of 1989, approximately 6.5 million gallons of contaminated groundwater were pumped from 23 wells at the Hoe Creek underground coal gasification site, near Gillette, Wyoming. The organic contaminants were removed using activated carbon before the water was sprayed on 15.4 acres at the sites. Approximately 2647 g (5.8 lb) of phenols and 10,714 g (23.6 lb) of benzene were removed from the site aquifers. Phenols, benzene, toluene, ethylbenzene, and naphthalene concentrations were measured in 43 wells. Benzene is the only contaminant at the site exceeds the federal standard for drinking water (5 {mu}g/L). Benzene leaches into the groundwater and is slow to biologically degrade; therefore, the benzene concentration has remained high in the groundwater at the site. The pumping operation affected groundwater elevations across the entire 80-acre site. The water levels rebounded quickly when the pumping operation was stopped on October 1, 1989. Removing contaminated groundwater by pumping is not an effective way to clean up the site because the continuous release of benzene from coal tars is slow. Benzene will continue to leach of the tars for a long time unless its source is removed or the leaching rate retarded through mitigation techniques. The application of the treated groundwater to the surface stimulated plant growth. No adverse effects were noted or recorded from some 60 soil samples taken from twenty locations in the spray field area. 20 refs., 52 figs., 8 tabs.

  17. Chemistry of Furan Conversion into Aromatics and Olefins over HZSM-5: A Model Biomass Conversion Reaction

    SciTech Connect (OSTI)

    Cheng, Yu-Ting [Univ. of Massachusetts, Amherst, MA (United States); Huber, George W. [Univ. of Massachusetts, Amherst, MA (United States)

    2011-06-03T23:59:59.000Z

    The conversion of furan (a model of cellulosic biomass) over HZSM-5 was investigated in a thermogravimetric analysis–mass spectrometry system, in situ Fourier transform infrared analysis, and in a continuous-flow fixed-bed reactor. Furan adsorbed as oligomers at room temperature with a 1.73 of adsorbed furan/Al ratio. These oligomers were polycyclic aromatic compounds that were converted to CO, CO?, aromatics, and olefins at temperatures from 400 to 600 °C. Aromatics (e.g., benzene, toluene, and naphthalene), oligomer isomers (e.g., benzofuran, 2,2-methylenebisfuran, and benzodioxane), and heavy oxygenates (C??{sub +} oligomers) were identified as intermediates formed inside HZSM-5 at different reaction temperatures. During furan conversion, graphite-type coke formed on the catalyst surface, which caused the aromatics and olefins formation to deactivate within the first 30 min of time on-stream. We have measured the effects of space velocity and temperature for furan conversion to help us understand the chemistry of biomass conversion inside zeolite catalysts. The major products for furan conversion included CO, CO?, allene, C?–C? olefins, benzene, toluene, styrene, benzofuran, indene, and naphthalene. The aromatics (benzene and toluene) and olefins (ethylene and propylene) selectivity decreased with increasing space velocity. Unsaturated hydrocarbons such as allene, cyclopentadiene, and aromatics selectivity increased with increasing space velocity. The product distribution was selective to olefins and CO at high temperatures (650 °C) but was selective to aromatics (benzene and toluene) at intermediate temperatures (450–600 °C). At low temperatures (450 °C), benzofuran and coke contributed 60% of the carbon selectivity. Several different reactions were occurring for furan conversion over zeolites. Some important reactions that we have identified in this study include Diels–Alder condensation (e.g., two furans form benzofuran and water), decarbonylation (e.g., furan forms CO and allene), oligomerization (allene forms olefins and aromatics plus hydrogen), and alkylation (e.g., furan plus olefins). The product distribution was far from thermodynamic equilibrium.

  18. anaerobic benzene communities: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and government. Forest Renewal BC funding- from stumpage fees and royalties that forest companies pay for the right to harvest timber on Crown lands- is reinvested in the forest,...

  19. Recovery of benzene in an organic vapor monitor

    E-Print Network [OSTI]

    Krenek, Gregory Joel

    1980-01-01T23:59:59.000Z

    solid adsorbents available (silica gel, activated alumina, etc. ), activated charcoal is most frequently utilized. Activated charcoal has retentivity for sorbed vapors several times that of silica gel and it displays a selectivity for organic vapors... (diffusion rate) of the vapor molecules to the sur- face of the adsorbent. The adsorption process determine how effective the adsorbent collects and holds the contam- inant on the surface of the activated charcoal. Recovery of the contaminant from...

  20. anaerobic benzene degradation: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hb, hemoglobin; MS, mass spectrometry; PBPK, physiologically based pharmacokinetic; SPC, S-phenylcysteine. Andrew B. Lindstrom; Suramya Waidyanatha; Rogelio Tonero-velez;...

  1. alkyl benzene sulfonate: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hb, hemoglobin; MS, mass spectrometry; PBPK, physiologically based pharmacokinetic; SPC, S-phenylcysteine. Andrew B. Lindstrom; Suramya Waidyanatha; Rogelio Tonero-velez;...

  2. alkyl benzene sulphonates: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hb, hemoglobin; MS, mass spectrometry; PBPK, physiologically based pharmacokinetic; SPC, S-phenylcysteine. Andrew B. Lindstrom; Suramya Waidyanatha; Rogelio Tonero-velez;...

  3. alkyl benzene sulfonates: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hb, hemoglobin; MS, mass spectrometry; PBPK, physiologically based pharmacokinetic; SPC, S-phenylcysteine. Andrew B. Lindstrom; Suramya Waidyanatha; Rogelio Tonero-velez;...

  4. aqueous benzene solutions: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and alternating current polarography of nitrobenzene in aqueous solutions and in acetonitrile. Open Access Theses and Dissertations Summary: ??The polarographic reduction of...

  5. Oxoanion Recognition by Benzene-based Tripodal Pyrrolic Receptors

    SciTech Connect (OSTI)

    Bill, Nathan [University of Texas at Austin; Kim, Dae-Sik [University of Texas at Austin; Kim, Sung Kuk [University of Texas at Austin; Park, Jung Su [University of Texas at Austin; Lynch, Vincent M. [University of Texas at Austin; Young, Neil J [ORNL; Hay, Benjamin [ORNL; Yang, Youjun [University of Texas at Austin; Anslyn, Eric [University of Texas at Austin; Sessler, Jonathan L. [University of Texas

    2012-01-01T23:59:59.000Z

    Two new tripodal receptors based on pyrrole- and dipyrromethane-functionalised derivatives of a sterically geared precursor, 1,3,5-tris(aminomethyl)-2,4,6-triethylbenzene, are reported; these systems, compounds 1 and 2, display high affinity and selectivity for tetrahedral anionic guests, in particular dihydrogen phosphate, pyrophosphate and hydrogen sulphate, in acetonitrile as inferred from isothermal titration calorimetry measurements. Support for the anion-binding ability of these systems comes from theoretical calculations and a single-crystal X-ray diffraction structure of the 2:2 (host:guest) dihydrogen phosphate complex is obtained in the case of the pyrrole-based receptor system, 1. Keywords anion receptors, dihydrogen phosphate, hydrogen sulphate, X-ray structure, theoretical calculations.

  6. Journal of Alloys and Compounds 449 (2008) 191195 Effects of plasma polymerized para-xylene intermediate layers

    E-Print Network [OSTI]

    Boo, Jin-Hyo

    2008-01-01T23:59:59.000Z

    terephthalate substrates Sunyoung Sohna, Kyuhyung Kima, Samil Khoa, Donggeun Junga,, Jin-hyo Boob a Department

  7. The Effect of Y-zeolite Acidity on m-Xylene Transformation Reactions S. Al-Khattaf*

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    of these aromatic hydrocarbons are the reforming and pyrolysis gasoline, which have a higher ratio of low-valued m

  8. A SPRAY REACTOR CONCEPT FOR CATALYTIC OXIDATION OF P-XYLENE TO PRODUCE HIGH-PURITY TEREPHTHALIC ACID

    E-Print Network [OSTI]

    LI, MENG

    2013-08-31T23:59:59.000Z

    analyzing and solving problems, about perseverance and staying positive when research hits a snag. Prof. Subramaniam has been and will always be a great mentor and an invaluable asset to me. Special thanks are also due to Prof. Daryle Busch, Prof. Raghunath...: T = 200 °C, P = 15 bar; Initial pX = 25 mM, Co = 12.5 mM, Mn = 12.5 mM, Br = 32.5 mM; O2:CO2 (mol:mol) = 1:1) ....................................42 Figure 2.9 Figure 2.9: Color changes of the reaction solution due to the formation of various cobalt...

  9. Waste properties of a strippable coating used for the TMI-2 reactor building decontamination

    SciTech Connect (OSTI)

    Dougherty, D.R.; Adams, J.W.; Barletta, R.E.

    1982-01-01T23:59:59.000Z

    Strippable coating material considered for use in the TMI-2 reactor building decontamination has been tested for Sr, Cs, and Co leachability, for radiation stability, and for resistance to biodegradation. It was also immersion tested in water, a water solution saturated with toluene and xylene, toluene, xylene, and liquid scintillation counting (LSC) cocktail. Leach testing, performed using a modified IAEA procedure, resulted in all of the Cs and Co activity and most of the Sr activity being released from the coating in just a few days. Immersion resulted in swelling of the coating in all of the liquids tested. Gamma irradiation of the coating did not produce any apparent physical changes in the coating to a dose of 1 x 10/sup 8/ rad, however, radiolytic gas generation of H/sub 2/, CO, and CO/sub 2/ was observed. Biodegradation testing was performed in soil samples from the Barnwell, South Carolina, and Hanford, Washington, low-level waste disposal sites. These test results indicate that strippable coating radwaste of itself will not meet the requirements for stabilized Class B waste outlined in 10 CFR 61 (proposed) and the NRC Draft Branch Technical Position on Waste Form.

  10. Strippable coating used for the TMI-2 reactor building decontamination

    SciTech Connect (OSTI)

    Adams, J.W.; Dougherty, D.R.; Barletta, R.E.

    1984-01-01T23:59:59.000Z

    Strippable coating material used in the TMI-2 reactor building decontamination has been tested for Sr, Cs, and Co leachability, for radiation stability, thermal stability, and for resistance to biodegradation. It was also immersion tested in water, a water solution saturated with toluene and xylene, toluene, xylene, and liquid scintillation counting (LSC) cocktail. Leach testing resulted in all of the Cs and Co activity and most of the Sr activity being released from the coating in just a few days. Immersion resulted in swelling of the coating in all of the liquids tested. Gamma irradiation and heating of the coating did not produce any apparent physical changes in the coating to 1 x 10/sup 8/ rad and 100/sup 0/C; however, gas generation of H/sub 2/, CO, CO/sub 2/ was observed in both cases. Biodegradation of the coating occurred readily in soils as indicated by monitoring CO/sub 2/ produced from microbial respiration. These test results indicate that strippable coating radwaste would have to be stabilized to meet the requirements for Class B waste outlined in 10 CFR Part 61 and the NRC Draft Technical Position on Waste Form.

  11. Selected Abstracts & Bibliography of International Oil Spill Research, through 1998

    E-Print Network [OSTI]

    Louisiana Applied Oil Spill Research & Development Program Electronic Bibliography

    1998-01-01T23:59:59.000Z

    to steady state on toluene were exposed to 50% toluene-50%grown JS6 cultures exposed to toluene. These results

  12. Characterization of the molecular structure and mechanical properties of polymer surfaces and protein/polymer interfaces by sum frequency generation vibrational spectroscopy and atomic force microscopy

    E-Print Network [OSTI]

    Koffas, Telly Stelianos

    2004-01-01T23:59:59.000Z

    polystyrene exposed to toluene vapor, and polystyrenethe case of polystyrene exposed to toluene. 26 Toluene is ainterface, (b) polystyrene exposed to toluene vapor, and (c)

  13. Photoluminescence characterization of polythiophene films incorporated with highly functional molecules such as metallophthalocyanine

    SciTech Connect (OSTI)

    Kobe, Hiroaki; Ohnaka, Kazumasa; Kato, Hitoshi; Takemura, Susumu; Shimada, Kazuhiro; Hiramatsu, Tomoyasu; Matsui, Kazunori [Department of Electrical, Electronic and Information Engineering, College of Engineering, Kanto Gakuin University, 1-50-1 Mutsuurahigashi, Kanazawa-ku, Yokohama 236-8501 (Japan); Department of Material and Life Science, College of Engineering, Kanto Gakuin University, 1-50-1 Mutsuurahigashi, Kanazawa-ku, Yokohama 236-8501 (Japan)

    2013-01-15T23:59:59.000Z

    The photoluminescence (PL) of conducting polymer polythiophene (PT) films incorporated with metallophthalocyanines (PcMs) such as CuPc, MgPc, FePc, Li{sub 2}Pc, and CoPc was studied by PL and time-correlated single photon counting (TCSPC) measurements. Polymer films were prepared by electrochemical polymerization and PcMs migrated into the polymer films by a diffusion method using acetonitrile or toluene as a solvent to dissolve the PcMs. The wavelength of PL emission peaks changed significantly depending on the solvent used in the doping process. Using acetonitrile, the observed PL emission peaks originated from the Q band, whereas they were assigned to the Soret band in the case of toluene. TCSPC measurements showed that PL emission took place through a ligand-ligand transition process when using acetonitrile because the average lifetimes were comparable and independent of the central metal ions for CoPc-, Li{sub 2}Pc-, and MgPc-doped polymer films. Conversely, using toluene, it was found that ligand-ligand emission occurred for Li{sub 2}Pc-, MgPc-, and FePc-doped films. To identify the cause of the drastic change in PL emission pattern, x-ray photoelectron spectroscopy measurements were obtained. A lower binding energy component appeared in the C 1s core-level spectra of acetonitrile-processed PcM-doped PT films, whereas this component shifted to higher energy and overlapped with the main peak for toluene-processed PcM-doped PT films. The lower binding energy component corresponded to photoelectrons due to the C atoms in the benzene rings of the ligand. Lower binding energy components also appeared in the N 1s core-level spectra of acetonitrile-processed PcM-doped PT films, and this component shifted to higher energy for toluene-processed PcM-doped PT films. These lower energy components were assigned to the core-level peaks due to the N atoms at the meso position bridging between pyrrole rings. This suggests that the electron charge at the N sites of the meso positions in toluene-processed films was smaller than in acetonitrile-processed ones. The changes in energy at benzene C sites and meso N sites suggest that the electronic states of the phthalocyanine in the toluene-processed films were porphyrin-like, so the Soret band became dominant in the PL emission spectrum.

  14. Processing of cyclopropylarenes by toluene dioxygenase: isolation and absolute configuration of metabolites

    E-Print Network [OSTI]

    Hudlicky, Tomas

    of fermentation were isolated by extrac- tion of the fermentation broth with base-washed ethyl acetate synthesis of natural products.1c,2 Reliable procedures have been published for the whole-cell fermentation the cyclopropylarenes6 listed in Table 1 and subjected them to the whole-cell fermentation protocol. The products

  15. Toluene dioxygenase-mediated oxidation of dibromobenzenes. Absolute stereochemistry of new metabolites

    E-Print Network [OSTI]

    Hudlicky, Tomas

    as optically pure material in total synthesis of natural products.2,3 The whole-cell fermentation of aromatic yields of the corresponding diols, which are easily extracted from the fermentation broth using base-washed ethyl acetate.3a The mechanism of the enzymatic oxidation remains un- known although some predictive

  16. A study of thermal diffusion in dilute solutions of polystyrene in toluene

    E-Print Network [OSTI]

    Herren, Cecil LeRoy

    1961-01-01T23:59:59.000Z

    . Tf then the rate of mctIcn cf molecule. . In the t?ro segments are determined from Fipure 4 usInp t'heir relative concentrations, It is seen that there is an over-runninp of r -. lymer solecules from the lever concentration rapists Into the h...

  17. Pyrolysis and Isomerization of Quadricyclane, Norbornadiene, and Toluene Zhi Li and Scott L. Anderson*

    E-Print Network [OSTI]

    Anderson, Scott L.

    class of molecules, both from a fundamental perspective and because they have potential as high-energy density materials. The high volumetric energy density arises mostly from the fact that these molecules tandem mass spectrometry. The methodology permits pyrolysis studies with product isomer identification

  18. Desorption efficiencies of toluene and n-butanol in an organic vapor monitor

    E-Print Network [OSTI]

    Heaney, Mary Ann

    1979-01-01T23:59:59.000Z

    ) ~ ~ ? Experimental Volume versus Theoretical Volume for n-Butanol (liquid phase). . . . . . . 13. Conceptual Adsorption of Vapor Molecules;. . . . 41 IXI'RODDCTI 019 In 1970, the Occupational Safety and Health Adminj- strstion adopted permissible human exposure...&jards has become one of the most important industrial hygiene f unct i one e The levei of exposure to many organic vapor;=, is det r- mined by co' lecting the chemical on some type o solid sor- bent. Of the various adsorbents available {silica gel...

  19. Experiment on TiO2/AC Photocatalysis Technique to Eliminate Toluene in Air Conditioning Systems

    E-Print Network [OSTI]

    Hu, Y.; Feng, G.; Yuan, Q.

    2006-01-01T23:59:59.000Z

    at present, the article proposes that new-type purification technique and hopes to promote the upgrading of the product about purification. 2. INTRODUTION ON THE STRURE AND STUFF OF ACTIVE CARBON AND NANO- TITANIUM DIOXIDE PHOTOCATALYSIS PURIFICATION... WEB What is called active carbon and nano-titanium dioxide photocatalysis technique is to utilize the method of compounding active carbon and nanometer photocatalyst to firstly form absorption layer on supporting body surface by gluing, which...

  20. A system for calibration of long term sampling with toluene detector tubes

    E-Print Network [OSTI]

    Yalcinkaya, Ayse Perihan

    1976-01-01T23:59:59.000Z

    is 9 the catalized reaction of some gaseous contaminants with each other arising from the closer molecular contact provided by the active sur- face of the substrate in the detector tube. B Since in most cases, a fixed volume of air sample... in magnitude compared to the other error sources in diffusion cells. 29 The temperature dependence of the diffusion coefficient is expressed as n D2 T2 Pl ? =( ? ) Dl Tl P2 (6) 2 where 0 and D are diffusion coefficients in ? at room temperatures cm 1...

  1. Desorption efficiencies of toluene and n-butanol in an organic vapor monitor 

    E-Print Network [OSTI]

    Heaney, Mary Ann

    1979-01-01T23:59:59.000Z

    (contained within the quiescent layer inside the dosimeter); that the collection effic'ency of the adsorbent is unity, and; that the effects of the monitor wa' ls are negligible. (~~ ~ ~-) The term D(A/L) i. , tho samplin- rate for the contaminant...

  2. Final Technical Report - Autothermal Styrene Manufacturing Process with Net Export of Energy

    SciTech Connect (OSTI)

    Trubac, Robert , E.; Lin, Feng; Ghosh, Ruma: Greene, Marvin

    2011-11-29T23:59:59.000Z

    The overall objectives of the project were to: (a) develop an economically competitive processing technology for styrene monomer (SM) that would reduce process energy requirements by a minimum 25% relative to those of conventional technology while achieving a minimum 10% ROI; and (b) advance the technology towards commercial readiness. This technology is referred to as OMT (Oxymethylation of Toluene). The unique energy savings feature of the OMT technology would be replacement of the conventional benzene and ethylene feedstocks with toluene, methane in natural gas and air or oxygen, the latter of which have much lower specific energy of production values. As an oxidative technology, OMT is a net energy exporter rather than a net energy consumer like the conventional ethylbenzene/styrene (EB/SM) process. OMT plants would ultimately reduce the cost of styrene monomer which in turn will decrease the costs of polystyrene making it perhaps more cost competitive with competing polymers such as polypropylene.

  3. University of Kansas Graduate School theses, 1888-1947

    E-Print Network [OSTI]

    Wilder, Bessie E.

    1949-01-01T23:59:59.000Z

    compes. M.A. Zool. 1927. The effect of temperature and the critical thermal increment for several species of amebas. Ph. D. Zool. 1933. Allen, Herman C. Instantaneous chemical reactions in benzene and toluene. M. A. Chem. 1905. Allis, Frank Howard... 1, 1927. M. A. Ed. 1928. Baldwin, Katrina. A study of the probable influence of the work of F. Hop- kinson Smith as painter and illustrator on his writings. M.A. Eng. 1933. Baldwin, Onias Barber. The maturation of the college student as evidenced...

  4. The stereochemistry and steric requirement of phosphonate Wittig reaction

    E-Print Network [OSTI]

    Tsen, Chung-Ye

    1973-01-01T23:59:59.000Z

    ) -activated olefin synthesis can be carried out under quite mild conditions in a suitable solvent (dimethyl formamide, 1, 2-dimethoxyethane, cyclo- hexane, benzene, toluene) . It has been found that in ether and anisole the olefin yields are low.... The ketones used in this study were 2 ? (3-butenyl)cyclohexanone (34), 2, 4, 4-trimethyl- cyclohexanone (35), 2-methyl-4-t-butylcyclohexanone (36), cis-cis-2, 6-dimethyl-4-t-butylcyclohexanone (37a), cis-trans-2, 6-dimethyl-4-t-butylcyclohexanone (37b...

  5. Comparison of advanced distillation control methods. Third annual report

    SciTech Connect (OSTI)

    Riggs, J.B.

    1997-07-01T23:59:59.000Z

    Detailed dynamic simulations of three industrial distillation columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to study the issue of configuration selection for diagonal PI dual composition controls, feedforward from a feed composition analyzer, and decouplers. Auto Tune Variation (ATV) identification with on-line detuning for setpoint changes was used for tuning the diagonal proportional integral (PI) composition controls. In addition, robustness tests were conducted by inducting reboiler duty upsets. For single composition control, the (L, V) configuration was found to be best. For dual composition control, the optimum configuration changes from one column to another. Moreover, the use of analysis tools, such as RGA, appears to be of little value in identifying the optimum configuration for dual composition control. Using feedforward from a feed composition analyzer and using decouplers are shown to offer significant advantages for certain specific cases.

  6. Superfund Record of Decision (EPA Region 2): Industrial Latex, Bergen County, Wallington, NJ. (First remedial action), September 1992

    SciTech Connect (OSTI)

    Not Available

    1992-09-30T23:59:59.000Z

    The 9.67-acre Industrial Latex site is a chemical adhesives and natural and synthetic rubber compounds manufacturer in Wallington, Bergen County, New Jersey. From 1951 to 1980, the Industrial Latex Corporation manufactured both chemical adhesives and natural and synthetic rubber compounds. Adhesives were initially formmulated using vegetable protein in a solvent base. The ROD addresses the final remedy for the contamination present in the soil, sediment, buildings and equipment, drums, sludge, septic system, and hardened latex, as the first of two operable units. The primary contaminants of concern affecting the soil, sediment, sludge, and debris are VOCs including PCE, TCE, toluene, and xylenes; other organics, including PAHs, PCBs, pesticides, and phenols; and metals, including arsenic and lead.

  7. Superfund record of decision (EPA Region 2): Imperial Oil/Champion Chemicals, Monmouth County, NJ. (Second remedial action), September 1992

    SciTech Connect (OSTI)

    Not Available

    1992-09-01T23:59:59.000Z

    The 9.67-acre Industrial Latex site is a chemical adhesives and natural and synthetic rubber compounds manufacturer in Wallington, Bergen County, New Jersey. From 1951 to 1980, the Industrial Latex Corporation manufactured both chemical adhesives and natural and synthetic rubber compounds. Adhesives were initially formulated using vegetable protein in a solvent base. The ROD addresses the final remedy for the contamination present in the soil, sediment, buildings and equipment, drums, sludge, septic system, and hardened latex, as the first of two operable units. The primary contaminants of concern affecting the soil, sediment, sludge, and debris are VOCs including PCE, TCE, toluene, and xylenes; other organics, including PAHs, PCBs, pesticides, and phenols; and metals, including arsenic and lead.

  8. Aerosol characterization study using multi-spectrum remote sensing measurement techniques.

    SciTech Connect (OSTI)

    Glen, Crystal Chanea; Sanchez, Andres L.; Lucero, Gabriel Anthony; Schmitt, Randal L.; Johnson, Mark S.; Tezak, Matthew Stephen; Servantes, Brandon Lee

    2013-09-01T23:59:59.000Z

    A unique aerosol flow chamber coupled with a bistatic LIDAR system was implemented to measure the optical scattering cross sections and depolarization ratio of common atmospheric particulates. Each of seven particle types (ammonium sulfate, ammonium nitrate, sodium chloride, potassium chloride, black carbon and Arizona road dust) was aged by three anthropogenically relevant mechanisms: 1. Sulfuric acid deposition, 2. Toluene ozonolysis reactions, and 3. m-Xylene ozonolysis reactions. The results of pure particle scattering properties were compared with their aged equivalents. Results show that as most particles age under industrial plume conditions, their scattering cross sections are similar to pure black carbon, which has significant impacts to our understanding of aerosol impacts on climate. In addition, evidence emerges that suggest chloride-containing aerosols are chemically altered during the organic aging process. Here we present the direct measured scattering cross section and depolarization ratios for pure and aged atmospheric particulates.

  9. Recovery of propylene glycol from dilute aqueous solutions by reversible chemical complexation with organoboronates

    SciTech Connect (OSTI)

    Broekhuis, R.R.; Lynn, S.; King, C.J.

    1995-05-01T23:59:59.000Z

    Extractants consisting of an ion-pair of Aliquat 336 with phenylboronate or 3-nitrophenylboronate were prepared in various diluents (2-ethylhexanol, toluene, o-xylene or diisobutylketone). In batch experiments propyleneglycol (1,2-PD) was effectively extracted even at low concentrations. Heterogeneous complexation constants {beta}{sub 11} calculated at 25 C were 45-120 (mol/1){sup {minus}1} in 2-ethylhexanol, 34.8 (mol/l){sup {minus}1} in toluene, 37.6 (mol/l){sup {minus}1} in o-xylene and 14.4 (mol/l){sup {minus}1} in diisobutylketone. In 2-ethythexanol, there was no significant effect of extractant concentration on the complexation constant. Equilibrium water concentration in the extractants was 8-12 wt %, decreasing with 1,2-PD uptake. Nearly all extractant/diluent systems exhibited overloading (more than stoichiometric uptake of 1,2-PD). Evidence for aggregation of the ion-pair extractant in organic phase was found from water solubilization studies (molar solubilization ratios up to 10) and {sup 1}H NMR spectroscopy studies. Solubilization of 1,2-PD within hydrophilic aggregate interiors may explain the observed overloading. The complexation constant decreased with increasing temperature, but not enough to make back extraction after a temperature change attractive. Back extraction may be achieved after acidification with carbon dioxide to convert the organoboronate anion to the corresponding organoboronic acid. Up to 80% of the extracted 1,2-PD was backextracted in a batch extraction using C0{sub 2}. The extractant could then be regenerated by stripping carbon dioxide from solution at temperatures exceeding 110 C. However, at these temperatures the extractant appears to undergo a transformation in which color changes and extraction capacity is reduced to about 60% of original value.

  10. Investigation of optical limiting properties of Aluminium nanoparticles prepared by pulsed laser ablation in different carrier media

    SciTech Connect (OSTI)

    Kuladeep, Rajamudili; Jyothi, L.; Narayana Rao, D. [School of Physics, University of Hyderabad, Prof. C. R. Rao Road, Hyderabad 500046 (India)] [School of Physics, University of Hyderabad, Prof. C. R. Rao Road, Hyderabad 500046 (India); Prakash, P.; Mayank Shekhar, S. [Center of Excellence in Lasers and Optoelectronic Sciences, International School of Photonics, Cochin University of Science and Technology, Kochi (India)] [Center of Excellence in Lasers and Optoelectronic Sciences, International School of Photonics, Cochin University of Science and Technology, Kochi (India); Durga Prasad, M. [Center for Nanotechnology, University of Hyderabad, Prof. C. R. Rao Road, Hyderabad 500046 (India)] [Center for Nanotechnology, University of Hyderabad, Prof. C. R. Rao Road, Hyderabad 500046 (India)

    2013-12-28T23:59:59.000Z

    In this communication, we carried out the systematic investigation of nonlinear absorption and scattering properties of Aluminium nanoparticles (Al NPs) in various polar and non-polar solvents. Al NPs were synthesized with pulsed Nd:YAG laser operated at 1064 nm by ablating Al target in polar and non-polar liquid environment like chloroform, chlorobenzene, toluene, benzene, and carbon tetrachloride. Synthesized Al NPs colloids of various solvents differ in appearance and UV-Vis extinction spectra exhibit absorption in the UV region. The characterization of Al NPs performed by Transmission electron microscopy (TEM) studies reveal that NPs are made up of a well crystallized Al inner part (bright zone) embedded with an amorphous metal Al shell (dark region). Growth, aggregation, and precipitation mechanisms which influence the optical properties and stability of NPs are found to be related to the dipole moment of the surrounding liquid environment. The nonlinear absorption and scattering studies are performed by open aperture Z-scan technique with 532 nm under nanosecond pulse excitation. The Z-scan measurements are fitted theoretically to estimate both two-photon absorption (TPA) and nonlinear scattering (NLS) coefficients. In polar solvents like chlorobenzene, chloroform synthesized Al NPs exhibited higher TPA, NLS coefficient values, and lower optical limiting threshold values in comparison with partially polar solvent like toluene and non-polar solvents like benzene and carbontetrachloride. These results indicate the potential use of Al NPs as a versatile optical limiting material.

  11. Carbon-Supported bimetallic Pd-Fe catalysts for vapor-phase hydrodeoxygenation of guaiacol

    SciTech Connect (OSTI)

    Sun, Junming; Karim, Ayman M.; Zhang, He; Kovarik, Libor; Li, Xiaohong S.; Hensley, Alyssa; McEwen, Jean-Sabin; Wang, Yong

    2013-10-01T23:59:59.000Z

    Abstract Carbon supported metal catalysts (Cu/C, Fe/C, Pd/C, Pt/C, PdFe/C and Ru/C) have been prepared, characterized and tested for vapor-phase hydrodeoxygenation (HDO) of guaiacol (GUA) at atmospheric pressure. Phenol was the major intermediate on all catalysts. Over the noble metal catalysts saturation of the aromatic ring was the major pathway observed at low temperature (250 °C), forming predominantly cyclohexanone and cyclohexanol. Substantial ring opening reaction was observed on Pt/C and Ru/C at higher reaction temperatures (e.g., 350 °C). Base metal catalysts, especially Fe/C, were found to exhibit high HDO activity without ring-saturation or ring-opening with the main products being benzene, phenol along with small amounts of cresol, toluene and trimethylbenzene (TMB). A substantial enhancement in HDO activity was observed on the PdFe/C catalysts. Compared with Fe/C, the yield to oxygen-free aromatic products (i.e., benzene/toluene/TMB) on PdFe/C increased by a factor of four at 350 °C, and by approximately a factor of two (83.2% versus 43.3%) at 450 °C. The enhanced activity of PdFe/C is attributed to the formation of PdFe alloy as evidenced by STEM, EDS and TPR.

  12. Rings sliding on a honeycomb network: Adsorption contours, interactions, and assembly of benzene on Cu(111)

    E-Print Network [OSTI]

    Einstein, Theodore L.

    by anthraquinone AQ on Cu 111 .3 The pore diameter is unprecedentally large, over 5 nm, and each cell encloses over

  13. Biomarkers of Leukemia Risk: Benzene Martyn T. Smith and Luoping Zhang

    E-Print Network [OSTI]

    California at Berkeley, University of

    Classification of Leukemia Leukemia is a cancer of the blood-forming further designated as acute or chronic system and has been defined as the uncon- leukemias. Acute leukemia is characterized trolled lineage affected, and can be leukemias: acute lymphocytic (ALL), This paper is based on a presentation

  14. Modeling Studies on the Transport of Benzene and H2S in CO2-Water Systems

    E-Print Network [OSTI]

    Zheng, L.

    2011-01-01T23:59:59.000Z

    Germann, 1969. Physical properties of hydrogen sulfide waterequilibrium properties of system carbon dioxide-hydrogenA thermodynamic property model for fluid phase hydrogen

  15. Comparison of benzene hexachloride formulated from high and low gamma concentrates for cotton aphid control 

    E-Print Network [OSTI]

    Raven, Klaus Gustav

    1957-01-01T23:59:59.000Z

    by KLAUS GUSTAV RAVEN Approved as to style and content by: (Chairman of Committee) (Head f Department) May 1957 ACKNOWLEDGEMENTS The writer would like to express his sincere appreciation to Dr. D. F. Martin for his constant encouragement and aid... technical material. Several processes have bees developed to soncentrate the gamsa isomer, Host processes are based on tha differential solubility of the ismsars in organic solvents. The solubility may be increased by vary- ing tha temperature...

  16. Novel Cholesteric Glassy Liquid Crystals Comprising Benzene Functionalized with Hybrid Chiral-Nematic Mesogens

    E-Print Network [OSTI]

    Chen, Shaw H.

    of Chemical Engineering, UniVersity of Rochester, Rochester, New York 14623-1212, and Laboratory for Laser reported herein. Films of the 1,3,5-trisubstituted and meta-disubstituted systems show a selective, including liquid crystals, tend to crystallize upon cooling through the melting point, Tm. Crystallization

  17. Evaluation of the pathways of tropospheric nitrophenol formation from benzene and phenol using a multiphase model 

    E-Print Network [OSTI]

    Heal, Mathew R; Harrison, Mark A J; Cape, Neil

    2005-01-01T23:59:59.000Z

    Phenols are a major class of volatile organic compounds (VOC) whose reaction within, and partitioning between, the gas and liquid phases affects their lifetime within the atmosphere, the local oxidising capacity, and the ...

  18. Assessment of Potential Benzene Contamination of the Ogallala Aquifer at the Pantex Plant, Texas

    E-Print Network [OSTI]

    Hazen, Terry

    National Laboratory Brian Looney, Savannah River Site Background and Objectives: In 1999 the Pantex Plant. A number of parallel investigations were initiated at the Pantex Plant, the Savannah River Technology Center, and the Pacific Northwest National Laboratory. The objective of this Independent Review

  19. DYNAMIC MODELING AND CONTROL OF REACTIVE DISTILLATION FOR HYDROGENATION OF BENZENE

    E-Print Network [OSTI]

    Aluko, Obanifemi

    2010-01-16T23:59:59.000Z

    . Otherwise, a rate-based mechanism is employed to describe the material and enrgy transfer between the liquid and vapor phases. The chemical reactions also introduce a structural difference between the models. Indeed, the chemical reactions can be either...

  20. Modeling Studies on the Transport of Benzene and H2S in CO2-Water Systems

    E-Print Network [OSTI]

    Zheng, L.

    2011-01-01T23:59:59.000Z

    Journal of Chemical and Engineering Data, 22(4): 399-401.Journal of Chemical and Engineering data, 11(1): 13-16.dioxide. Journal of Chemical and Engineering Data, 25(3):

  1. Modeling Studies on the Transport of Benzene and H2S in CO2-Water Systems

    E-Print Network [OSTI]

    Zheng, L.

    2011-01-01T23:59:59.000Z

    PAHs), and (4) its high partition coefficient between SCC and water.in production waters RøeUtvik (1999) BTEX PAHs Phenols TablePAHs and phenols concentration (mg/L) in production waters

  2. Modeling Studies on the Transport of Benzene and H2S in CO2-Water Systems

    E-Print Network [OSTI]

    Zheng, L.

    2011-01-01T23:59:59.000Z

    potential effects of carbon capture and geologic storage (CCS)CCS and groundwater resources (Birkholzer et al. , 2008), we evaluated the potentialCCS operations. Therefore, TMVOC_REACT was used to assess the potential

  3. The synthesis of benzene in the protoplanetary nebula CRL618 Paul M. Woods

    E-Print Network [OSTI]

    Millar, Tom

    . It is abundant on Earth (in petrol, plastics, detergents, etc.), and also more widely in the Solar System (in

  4. Non-Incineration Treatment to Reduce Benzene and VOC Emissions from Green Sand Molding Systems

    SciTech Connect (OSTI)

    Fred S. Cannon; Robert C. Voigt

    2002-06-28T23:59:59.000Z

    Final report describing laboratory, pilot scale and production scale evaluation of advanced oxidation systems for emissions and cost reduction in metal casting green sand systems.

  5. Modeling Studies on the Transport of Benzene and H2S in CO2-Water Systems

    E-Print Network [OSTI]

    Zheng, L.

    2011-01-01T23:59:59.000Z

    reservoir to shallower formations, for example through fault or fracture zones, or poorly plugged abandoned

  6. Comparison of benzene hexachloride formulated from high and low gamma concentrates for cotton aphid control

    E-Print Network [OSTI]

    Raven, Klaus Gustav

    1957-01-01T23:59:59.000Z

    in laboratory toxicity tests conducted during susaer 1955. 26 Median lethal doses snd average fiducial 1inits at the 5 psr cent level, calculated fran dosage- nortality curves, for ten fornulstions of BHC and parathion, twenty-four hours after treatneat... of the cotton aphid obtained during sussaer and tall 19S5 with BHC fornulstions as indicated. 39 9. Analysis of variaace of per cent control of the cotton aphid in toxicity tests conducted during sunner and fall 1955. 40 10. Average per cent control...

  7. Modeling Studies on the Transport of Benzene and H2S in CO2-Water Systems

    E-Print Network [OSTI]

    Zheng, L.

    2011-01-01T23:59:59.000Z

    Gu and Evans, 2007) (Bradbury and Baeyens, 2005) Sme s _OPb + Sme w _OPb + Sme s _OPb + + H + = Sme s _OH + Pb +2 Sme w _OPb + +

  8. The effect of benzene hexachloride-DDT spray on the insect population and the cotton plant

    E-Print Network [OSTI]

    Lloyd, Edwin Phillips

    1952-01-01T23:59:59.000Z

    IOXSMI) ~ oatteeasoeoe ~ sasooaaeeo?eeosotap ~ of ~~ ~ed ~ INK ~IILX%4 @5+ W N@l@+~)tasaosesagfoat' ~ aaO3ya9u of T~ ~) (T3O38 E~+mA)ya. . . t a3ao fcneQ 4o he ~ effeet4ve Se ooutraQ5ng the hgt waepLl g@@gcigg @~i~ Bobcat?aul 4hs oottou a~ ~ ~gggg ~? X... pears Caro haa heeu cL yuMcraX 4zemk Rn menp areas frau the uae of Gusts 4o %he uae of ~ fouuuhrhious or cdl ema1sious Ln cotton Sxreo4 eoutaeX. $5s usa 4he msem uaeL to so%vs the geohbe of vol em%4 Beck~ 9e 4he spgf;oe4tou ef e chN4 8ytzya seu ha ep...

  9. Modeling Studies on the Transport of Benzene and H2S in CO2-Water Systems

    E-Print Network [OSTI]

    Zheng, L.

    2011-01-01T23:59:59.000Z

    synthetic aluminous goethite before and after transformationAdsorption of lead(ll) on the goethite surface: voltammetric5.35.   Profile of the goethite volume fraction change (

  10. Batch polymerization of styrene initiated by n-butyllithium in benzene

    E-Print Network [OSTI]

    Tanlak, Tayfun

    1975-01-01T23:59:59.000Z

    with Hamilton 1LFl inert valves were used. The syringes, needles and valves were washed w1th detergent and water, rinsed with d1stilled water and dried in heated vacuum ovens. After drying, the equipment was e1ther immediately used or was stored in glass... was first purged with PPN to strip any dissolved gases. The stripped styrene was forced, by PPN overpressure, through a column of silica gel and into the evacuated pot of a vacuum st111. In order to prevent thermal polymerizat1on due to excess1ve...

  11. Carbon Nanothreads from Compressed Benzene | U.S. DOE Office of Science

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurTheBrookhaven National Laboratory Laboratory Policy (LP) LPCMSNF

  12. A quantitative relationship between structure and reactivity for the reactions between diphenyldiazomethanes and benzoic acids in toluene at 25° C

    E-Print Network [OSTI]

    Westmoreland, John Sherman

    1958-01-01T23:59:59.000Z

    is directly proportional to its concentration equation (11) may be written 27S. Glasstone, "Textbook of Physical Chemistry," 2nd ed., D. Van Nostrand Company, Inc., New York, N. Y., 19^ -6, P? 1051. 20 kr C = f r f ^ 7 (log 0DX - log 0D2) (12... is independent of the effect of m- or ?-substituents on the benzoic acid. 29 BIBLIOGRAPHY E. D. Barnett and M. A. Matthews, J. Chem* Soc., 125, 767 (1924). F. K. Beilstein, "Handbuch der Organischen Chemie", 4th Ed., J* Springer, Berlin, 1929* S. Glasstone...

  13. Phase Transitions and Phase Miscibility of Mixed Particles of Ammonium Sulfate, Toluene-Derived Secondary Organic Material,

    E-Print Network [OSTI]

    related to air quality and climate. The phases of particles containing secondary organic materials (SOMs humidity (RH), and temperature.2-5 Phase transitions of crystalline inorganic materials commonly found-8 These materials change from a crystalline solid to a saturated aqueous solution at the deliquescence relative

  14. Methods for chemical recovery of non-carrier-added radioactive tin from irradiated intermetallic Ti-Sb targets

    DOE Patents [OSTI]

    Lapshina, Elena V. (Troitsk, RU); Zhuikov, Boris L. (Troitsk, RU); Srivastava, Suresh C. (Setauket, NY); Ermolaev, Stanislav V. (Obninsk, RU); Togaeva, Natalia R. (Obninsk, RU)

    2012-01-17T23:59:59.000Z

    The invention provides a method of chemical recovery of no-carrier-added radioactive tin (NCA radiotin) from intermetallide TiSb irradiated with accelerated charged particles. An irradiated sample of TiSb can be dissolved in acidic solutions. Antimony can be removed from the solution by extraction with dibutyl ether. Titanium in the form of peroxide can be separated from tin using chromatography on strong anion-exchange resin. In another embodiment NCA radiotin can be separated from iodide solution containing titanium by extraction with benzene, toluene or chloroform. NCA radiotin can be finally purified from the remaining antimony and other impurities using chromatography on silica gel. NCA tin-117m can be obtained from this process. NCA tin-117m can be used for labeling organic compounds and biological objects to be applied in medicine for imaging and therapy of various diseases.

  15. Fossil fuel and hydrocarbon conversion using hydrogen-rich plasmas. Topical report February 1994--February 1995

    SciTech Connect (OSTI)

    NONE

    1995-02-01T23:59:59.000Z

    Experiments were made on use of H and CH plasmas for converting waste materials and heavy oils to H-rich transportation fuels. Batch and continuous experiments were conducted with an industrial microwave generator and a commercial microwave oven. A continuously circulating reactor was constructed for conducting experiments on flowing oils. Experiments on decomposition of scrap tires showed that microwave plasmas can be used to decompose scrap tires into potentially useful liquid products. In a batch experiment using a commercial microwave oven, about 20% of the tire was converted to liquid products in about 9 minutes. Methane was decomposed in a microwave plasma to yield a liquid products composed of various compound types; GC/MS analyses identified unsaturated compounds including benzene, toluene, ethyl benzene, methyl and ethyl naphthalene, small amounts of larger aromatic rings, and olefinic compounds. Experiments on a crude oil in a continuously flowing reactor showed that distillate materials are produced using H and CH plasmas. Also, the recycle oils had an overall carbon aromaticity lower than that of starting feed material, indicating that some hydrogenation and methanation had taken place in the recycle oils.

  16. Interfacial Synthesis of Dendritic Platinum Nanoshells Templated on Benzene Nanodroplets Stabilized in Water by a Photocatalytic Lipoporphyrin

    E-Print Network [OSTI]

    Shelnutt, John A.

    nano- particles, nanorods, nanowires, nanotubes, nanodendrites, and shape- controlled nanoparticles have been reported.2 Pt nanostructures with hollow interiors (nanoshells) are rare,3 even though Emulsion droplets have long been used as templates for synthesizing hollow nanostructures composed of glass

  17. Anhydrous ferric chloride as an alkylation catalyst: The condensation of 2-methylpropene and benzene, preparation and identification of several fractions.

    E-Print Network [OSTI]

    Mommessin, Pierre Robert

    1950-01-01T23:59:59.000Z

    Lg T: I snoop /~qua ep ? polio mn'[IunIp snoop. &qua 'op:zonI. xzg uo'oq 'oppxc+uad snzoqdsoqd 'pgoa o-?zngIos 'ap-=onIg ue3ozpZq sa qons 'sos. . Ie'=- plo'-' 1 c acTTa e Jd aqua uQ suoqgT oogppq ot )gmo Te qf~ $ese J IIT+ sane&Ia g&qq. emI~ amos... -uesezo. Qq~ , T eosazuao, qq. . ~ aueguq Pua . ue~::nod ~o uotgus -ueP too ev", PetPuq s Pixatsvnoty, Puu 'B?og 'Butuatip Q' "g J. elQ J euagnq-u erg qgtsp. Qe. ~-. aqqa eZV. SgtuSa Zattmtg Ouasueo. -tfiouo--. , see-tap pu- euez, :aqtfi. ?nq...

  18. Application of binary parameters to the ternary cyclohexane/polybutadiene/benzene system using open tubular columns in gas chromatography 

    E-Print Network [OSTI]

    Tsotsis, Thomas Karl

    1986-01-01T23:59:59.000Z

    Analysis of Multicomponent Systems by Chromatography . Polymer-Polymer Interaction Present State of the Application of Polymer . 'iolution Theories SOLUTION THEORIES . 1 2 3 4 5 6 7 8 F lory-I I uggins Flory-Prigogine Equation of State... measurements by showing good agreement. between glc and equilibriuin sorption (static) data. This work also established guidelines for the useful application of the glc method to polymer solution thermodynamics. In contrast to the work of Schreiber, et al...

  19. Displacement of oil by carbon dioxide. Annual report, October 1, 1980-September 30, 1981. [Ethyl benzene, ethylbutyrate, isopropanol

    SciTech Connect (OSTI)

    Orr, F.M. Jr.; Taber, J.J.

    1982-03-01T23:59:59.000Z

    Progress of a comprehensive research program to quantify factors affecting CO/sub 2/ flood displacement efficiency is described. Experimental and theoretical investigations of the interactions of factors such as phase behavior and fluid properties of CO/sub 2/-crude oil mixtures, and heterogeneities in reservoir rocks are discussed. Literature on the interpretation of miscible displacements in one- and two-phase systems is reviewed. Simple displacement experiments to evaluate effects of core heterogeneities and high mobile water saturations are described. Results of miscible displacement experiments with fluids of matched density and viscosity are presented and compared with results of a few displacements in which fluid properties were not matched. Those comparisons clearly indicate that control of viscous fingering is required if short core floods are to be interpreted with reasonable certainty. Detailed results of investigations of the phase behavior of CO/sub 2/-crude oil mixtures are presented. The volumetric behavior of mixtures of CO/sub 2/ with dead oils from the Wasson and Maljamar fields are compared with that of a Maljamar recombined reservoir fluid. The results provide the basis for a qualitative analysis of the effects of the presence of solution gas on CO/sub 2/ flood performance. Modifications to improve the continuous multiple contact experiment, which efficiently measures phase compositions and fluid properties, are described. An analysis of the operation of the apparatus is given for binary systems. The theory is compared with experimental results for CO/sub 2/-decane displacements, with excellent agreement. Extensive results of experiments to measure compositions and densities of phases present for CO/sub 2/-crude oil mixtures are reported.

  20. Quantification of black carbon in marine systems using the benzene polycarboxylic acid method: a mechanistic and yield study

    E-Print Network [OSTI]

    Ziolkowski, Lori A; Chamberlin, A.R.; Greaves, John; Druffel, Ellen R.M.

    2011-01-01T23:59:59.000Z

    GC/MS and NMR as 100% anthraquinone. Oxidation of anthracenehas been found to produce anthraquinone (Cho 1995).We hypothesize that the anthraquinone gener- ated was then

  1. Numerical Model Investigation for Potential Methane Explosion and Benzene Vapor Intrusion Associated with High-Ethanol Blend

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    ABSTRACT: Ethanol-blended fuel releases usually stimulate methanogenesis in the subsurface, which could conditions exist. Ethanol- derived methane may also increase the vapor intrusion potential of toxic fuel to be modified when dealing with some high ethanol blend fuel (i.e., E20 up to E95) releases. INTRODUCTION

  2. Catalytic cracking of n-Dodecane and Alkyl benzenes over FCC Zeolite Catalysts: Time on Stream and Reactant Converted Models

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    hydrocarbon model compounds (n-dodecane, 1,3,5- triisopropylbenzene, and 1,4-diisopropylbenzene) has been investigated over two FCC zeolite catalysts in a novel riser simulator that resembles closely the operating compounds. This can be due to the smaller ZSM-5 pore diameter (in the range of 5-6 Å) that restricts alkyl

  3. 8480 J. Am. Chem. SOC.1995,117, 8480-8481 A Boron Analogue of Benzene: Synthesis,

    E-Print Network [OSTI]

    Fu, Gregory C.

    ).6-9 Crystallization of 1 (1) For reviews of aromaticity and heteroaromaticity, see: (a) Simkin, B. Y.; Glukhovtsev, M. N.; Simkin, B. Y. Aromaticity and Antiaromaticity: Electronic and Structural Aspects; Wiley

  4. A study of the condensation of propene and isobutene with benzene in the presence of anhydrous ferric chloride

    E-Print Network [OSTI]

    Carpenter, Louis Linden

    1938-01-01T23:59:59.000Z

    . Distillsdioa of Csadeasaiioa Products osiag Porrio Chlosido aa4 JGaajaaa Chlox'ido ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ IC II. Kssillatioa of Polyaorkxaaioa Pzodue1s asiad Povris Chio&do sad Aloaiaaa Chlos ido ~ e ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ e l... (lygs) ~ due te the higher parity ef the slhoao whish was eeadeaood with tho areastio hfdrsearboa. lsobatsae pr?yare4 bf the dehydratiea ef tertiarf batrl sloohel is reported te have a parity greater thea 99 yer coat Qsiag oqaiaelsr ssswats...

  5. Reduction of perturbation gas chromatographic data to equilibrium sorption isotherms with application to the ternary benzene / polybutadiene / cyclohexane system

    E-Print Network [OSTI]

    Ruff, William Arthur

    1984-01-01T23:59:59.000Z

    on volume or segment fractions, the Flory equation-of-state theory and its simplication by Bonner and Prausnitz, and the lattice fluid theory of Sanchez and Lacombe. The determination involves a parameter estimation technique which simultaneously fits a... OF TABLES . LIST OF FIGURES . INTRODUCTION THEORY PERTURBATION GAS CHROMATOG~ THEORY POLYMER SOLUTION THEORY Flory-Huggins Lattice Theory Flory Equations-State Theory Simplified Flory Theory Sanchez and Lacombe Lattice Fluid Theory Brief Comparison...

  6. Application of binary parameters to the ternary cyclohexane/polybutadiene/benzene system using open tubular columns in gas chromatography

    E-Print Network [OSTI]

    Tsotsis, Thomas Karl

    1986-01-01T23:59:59.000Z

    Sanchez-Lacombe Lattice Fluid Model PERTURBATION CHROMATOGRAPHY 10 13 17 Application and Theory Open Tubular Column Comparison with Static Methods 17 19 19 vu TABLE OF CONTENTS (Continued) Page EXPERIMENTAL METHODS Static Measurement.../solvent behavior. Later workers made modifications to Flory's theory and, in the late 1970's, Sanchez and Lacombe'" ' developed a. La& tie&i Flu ?I &nodcl & o pr&dict poly&ner & s&ilvcni behavior. A more detailed discussion of' these ih&ori&s is presented later...

  7. Assessment of anaerobic benzene degradation potential using 16S rRNA gene-targeted real-time PCR

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    in the USA that are contaminated with gasoline leaks from underground storage tanks (UST) (USEPA, 2005 to remediate more than 50% of the existing gasoline-contaminated UST sites (USEPA, 2000). However

  8. An investigation of the thermal degradation mechanisms of a waste tire through chemical analysis including hydrocarbons, benzene derivatives, and Polycyclic

    E-Print Network [OSTI]

    to that of coal[2, 3]. However, their heterogeneity creates issues with regard to complete burnout and emissions, such as gasification and oxy-fuel combustion. Considerable study has been done investigating the overall gasification has been focused on pyrolysis/gasification and combustion at various oxygen concentrations

  9. Benzene-derived N2-(4-hydroxyphenyl)-deoxyguanosine adduct: UvrABC incision and its conformation in DNA

    E-Print Network [OSTI]

    Hang, Bo

    2010-01-01T23:59:59.000Z

    P-postlabeling. Carcinogenesis Malta, E. , Moolenaar, G.F. ,J Biol Chem 281, 2184-2194. Malta, E. , Verhagen, C.P. ,interactions with damaged DNA (Malta et al. , 2006; Malta et

  10. Comparison of advanced distillation control methods. Fourth annual report

    SciTech Connect (OSTI)

    Riggs, J.B.

    1998-09-01T23:59:59.000Z

    Detailed dynamic simulations of three industrial columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to evaluate configuration selection for single-ended and dual-composition control as well as compare conventional and advanced control approaches. For each case considered, the controllers were tuned by using setpoint changes and tested using feed composition upsets. Proportional Integral (PI) control performance was used to evaluate the configuration selection problem. For single ended control, the energy balance configuration was found to yield the best performance. For dual composition control, nine configurations were considered. It was determined that in order to identify the optimum configuration, detailed testing using dynamic simulation is required. The optimum configurations were used to evaluate the control performance of conventional PI controllers, DMC (Dynamic Matrix Control), PMBC (Process Model Based Control), and ANN (Artificial Neural Networks) control. It was determined that DMC works best when one product is much more important than the other while PI was superior when both products were equally important. PMBC and ANN were not found to offer significant advantages over PI and DMC.

  11. Comparison of advanced distillation control methods. Second annual report

    SciTech Connect (OSTI)

    NONE

    1996-11-01T23:59:59.000Z

    Detailed dynamic simulations of three industrial distillation columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to study the issue of configuration selection for diagonal PI dual composition controls. ATV identification with on-line detuning was used for tuning the diagonal PI composition controllers. Each configuration was evaluated with respect to steady-state RGA values, sensitivity to feed composition changes, and open loop dynamic performance. Each configuration was tuned using setpoint changes over a wider range of operation for robustness and tested for feed composition upsets. Overall, configuration selection was shown to have a dominant effect upon control performance. Configuration analysis tools (e.g., RGA, condition number, disturbance sensitivity), were found to reject configuration choices that are obviously poor choices, but were unable to critically differentiate between the remaining viable choices. Configuration selection guidelines are given although it is demonstrated that the most reliable configuration selection approach is based upon testing the viable configurations using dynamic column simulators.

  12. Comparison of advanced distillation control methods. Second annual report

    SciTech Connect (OSTI)

    Riggs, J.B.

    1996-11-01T23:59:59.000Z

    Detailed dynamic simulations of two industrial distillation columns (a propylene/propane splitter and a xylene/toluene column) have been used to study the issue of configuration selection for diagonal PI dual composition controls. Auto Tune Variation (ATV) identification with on-line detuning was used for tuning the diagonal proportional integral (PI) composition controls. Each configuration was evaluated with respect to steady-state relative gain array (RGA) values, sensitivity to feed composition changes, and open loop dynamic performance. Each configuration was tuned using setpoint changes over a wider range of operation for robustness and tested for feed composition upsets. Overall, configuration selection was shown to have a dominant effect upon control performance. Configuration analysis tools (e.g., RGA, condition number, disturbance sensitivity) were found to reject configuration choices that are obviously poor choices, but were unable to critically differentiate between the remaining viable choices. Configuration selection guidelines are given although it is demonstrated that the most reliable configuration selection approach is based upon testing the viable configurations using dynamic column simulators.

  13. Studies of Immobilized Homogeneous Metal Catalysts on Silica Supports

    SciTech Connect (OSTI)

    Keith James Stanger

    2003-05-31T23:59:59.000Z

    The tethered, chiral, chelating diphosphine rhodium complex, which catalyzes the enantioselective hydrogenation of methyl-{alpha}-acetamidocinnamate (MAC), has the illustrated structure as established by {sup 31}P NMR and IR studies. Spectral and catalytic investigations also suggest that the mechanism of action of the tethered complex is the same as that of the untethered complex in solution. The rhodium complexes, [Rh(COD)H]{sub 4}, [Rh(COD){sub 2}]{sup +}BF{sub 4}{sup -}, [Rh(COD)Cl]{sub 2}, and RhCl{sub 3} {center_dot} 3H{sub 2}O, adsorbed on SiO{sub 2} are optimally activated for toluene hydrogenation by pretreatment with H{sub 2} at 200 C. The same complexes on Pd-SiO{sub 2} are equally active without pretreatments. The active species in all cases is rhodium metal. The catalysts were characterized by XPS, TEM, DRIFTS, and mercury poisoning experiments. Rhodium on silica catalyzes the hydrogenation of fluorobenzene to produce predominantly fluorocyclohexane in heptane and 1,2-dichloroethane solvents. In heptane/methanol and heptane/water solvents, hydrodefluorination to benzene and subsequent hydrogenation to cyclohexane occurs exclusively. Benzene inhibits the hydrodefluorination of fluorobenzene. In DCE or heptane solvents, fluorocyclohexane reacts with hydrogen fluoride to form cyclohexene. Reaction conditions can be chosen to selectively yield fluorocyclohexane, cyclohexene, benzene, or cyclohexane. The oxorhenium(V) dithiolate catalyst [-S(CH{sub 2}){sub 3}s-]Re(O)(Me)(PPh{sub 3}) was modified by linking it to a tether that could be attached to a silica support. Spectroscopic investigation and catalytic oxidation reactivity showed the heterogenized catalyst's structure and reactivity to be similar to its homogeneous analog. However, the immobilized catalyst offered additional advantages of recyclability, extended stability, and increased resistance to deactivation.

  14. Bioinformatic characterization of the 4-Toluene Sulfonate Uptake Permease (TSUP) family of transmembrane proteins : identification of the microbial rhodopsin superfamily and evidence for an ancestral transmembrane hairpin structure

    E-Print Network [OSTI]

    Shlykov, Maksim Aleksandrovich

    2011-01-01T23:59:59.000Z

    synthesis: Co 2+ , Ni 2+ and riboflavin transport Transportmost likely transports riboflavin, seeing as FMN, FAD and

  15. Real refractive indices and volatility of secondary organic aerosol generated from photooxidation and ozonolysis of limonene, -pinene and toluene upon heating

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    C to approximately 20% at 95 ºC due to additional thermophoretic forces [Burtscher et al., 2001]. Above 50 nm

  16. doi:10.1016/j.gca.2005.06.029 Solubility of metallic mercury in octane, dodecane and toluene at temperatures between

    E-Print Network [OSTI]

    Long, Bernard

    Hg in natural systems, which may explain the high concentrations of metallic mercury in some crude oils, as well as the common occurrence of petroleum in epithermal mercury deposits. Copyright © 2005 of appreciable concentrations of Hg in crude oils (up to several 10's of ppm, Wilhelm and Bloom, 2000), little

  17. Supplement for "Wavelength-and NOx-dependent complex refractive index of1 SOA generated from photooxidation of toluene" by T. Nakayama et al.2

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    ) was also calibrated using gaseous light absorption by NO2. Gaseous mixtures of44 NO2/air (1-6 ppmv) were with polydisperse33 propane soot particles. Calibration factors for the babs() were estimated by comparing the bsca prepared by diluting 10 ppmv NO2 (Japan Fine Products) in air with synthetic45 air and then supplied

  18. Effect of Key Parameters on the Photocatalytic Oxidation of Toluene at Low Concentrations in Air under 254 + 185 nm UV Irradiation

    E-Print Network [OSTI]

    Quici, Natalia

    2010-01-01T23:59:59.000Z

    by heterogeneous photocatalysis, in Waste gas treatment forCincinnati, Ohio, USA d Photocatalysis and PhotoreactionCincinnati, Ohio, USA. d Photocatalysis and Photoreaction

  19. DIVALENT LANTHANIDE CHEMISTRY; BIS (PENTAMETHYLCYCLOPENTADIENYL) EUROPIUM(II) AND YTTERBIUM(II) DERIVATIVES: CRYSTAL STRUCTURE OF BIS(PENTAMETHYLCYCLOPENTADIENYL) YTTERBIUM (II)TETRAHYDROFURAN HEMI (TOLUENE) AT 176K

    E-Print Network [OSTI]

    Tilley, T.Don

    2012-01-01T23:59:59.000Z

    PENTAMETHYL CYCLOPENTADIENYL)EUROPIUM(II) AND YTTERBIUM(II)pentamethylcyclopentadienide and europium trichloride inbiscyclopentadienyl- europium and ~ytterbium, respectively,

  20. Design and optimization of polymeric silole and boronate photoluminescent probes for improved explosives detection applications

    E-Print Network [OSTI]

    Sanchez, Jason C.

    2008-01-01T23:59:59.000Z

    exposed to common organic solvents such as THF, toluene, andare exposed to common organic solvents such as THF, toluene,toluene to observe the spectral effects of different explosive analytes when exposed

  1. Tuning surface chemistry and nanostructure in porous silicon for molecular separation, detection and delivery /

    E-Print Network [OSTI]

    Wu, Chia-Chen

    2013-01-01T23:59:59.000Z

    humidity. (A) Sample exposed to 490 ppm toluene vapor afterRH; (B) sample exposed to 490 ppm toluene vapor after pre-from a sensor exposed to a stream of toluene vapor; the

  2. Manipulation of surface chemistry and nanostructure in porous silicon-based chemical sensors

    E-Print Network [OSTI]

    Ruminski, Anne Marie

    2009-01-01T23:59:59.000Z

    represents double stacks exposed to toluene (black squares),Sample was exposed to three concentrations of toluene (510,of Toluene with a Double Stack The double stack was exposed

  3. Superfund Record of Decision (EPA Region 2): Higgins Farm, Franklin Township, Somerset County, NJ. (First remedial action), September 1990

    SciTech Connect (OSTI)

    Not Available

    1990-09-24T23:59:59.000Z

    The 75-acre Higgins Farm site is a cattle farm in Franklin Township, Somerset County, New Jersey. The site is primarily pasture land with poor onsite drainage. Approximately 3,200 residents living within a three-mile radius of the site rely on ground water as their drinking water source. In 1985, after receiving reports of ground water contamination near the farm, the State investigated the area and found a drum burial area. In 1986, the site owner began to remove the drums from the site, and ten drums were removed, crushed and placed in a roll-off container. Later in 1986, another 50 drums were excavated, and during the excavation the drums were punctured and their contents spilled onto the ground. In late 1986, State site inspections revealed ground water and soil contamination by VOCs, pesticides, metals, and dioxins. The Record of Decision (ROD) provides a permanent safe drinking water supply source for affected residents as part of an interim remedy. A future ROD will address remediation of final ground water and all remaining onsite contamination including soil, sediment, surface water, and ground water. The primary contaminants of concern affecting the ground water are VOCs including benzene, PCE, TCE, and xylenes; other organics; and metals including lead.

  4. Surface Area and Microporosity of Carbon Aerogels from Gas Adsorption and Small- and Wide-Angle X-ray Scattering Measurements

    E-Print Network [OSTI]

    David Fairén-jiménez; Francisco Carrasco-marín; David Djurado; Françoise Bley; Françoise Ehrburger-dolle; Carlos Moreno-castilla

    2005-01-01T23:59:59.000Z

    A carbon aerogel was obtained by carbonization of an organic aerogel prepared by sol-gel polymerization of resorcinol and formaldehyde in water. The carbon aerogel was then CO2 activated at 800 °C to increase its surface area and widen its microporosity. Evolution of these parameters was followed by gas adsorption and small- and wide-angle X-ray scattering (SAXS and WAXS, respectively) with contrast variation by using dry and wet (immersion in benzene and m-xylene) samples. For the original carbon aerogel, the surface area, SSAXS, obtained by SAXS, is larger than that obtained by gas adsorption (Sads). The values become nearly the same as the degree of activation of the carbon aerogel increases. This feature is due to the widening of the narrow microporosity in the carbon aerogel as the degree of activation is increased. In addition, WAXS results show that the short-range spatial correlations into the assemblies of hydrocarbon molecules confined inside the micropores are different from those existing in the liquid phase. 1.

  5. Electrocatalytic reduction of carbon dioxide to carbon monoxide by rhenium and manganese polypyridyl catalysts

    E-Print Network [OSTI]

    Smieja, Jonathan Mark

    2012-01-01T23:59:59.000Z

    Si surface was exposed to Re(CO) 5 Cl in toluene at elevatedexposed to solution. Those vials were placed in a flask that also contained toluene and

  6. Responses of the L51781Y tk/sup +//tk/sup -/ mouse lymphoma cell forward mutation assay: III. 72 coded chemicals

    SciTech Connect (OSTI)

    McGregor, D.B.; Brown, A.; Cattanach, P.; Edwards, I.; McBride, D.; Riach, C.; Caspary, W.J.

    1988-01-01T23:59:59.000Z

    Seventy-two chemicals were tested for their mutagenic potential in the L51781Y tk/sup +///sup -/ mouse lymphoma cell forward mutation assay, using procedures based upon those described previously. Cultures were exposed to the chemicals for 4 hr, then cultured for 2 days before planting in soft agar with or without trifluorothymidine (TFT), 3 ..mu..g/ml. The chemicals were tested at least twice. Significant responses were obtained with allyl isothiocyanate, p-benzoquinone dioxime, benzyl acetate, 2-biphenylamine HCl, bis(2-chloro-1-methylethyl)ether, cadmium chloride, chlordane, chlorobenzene, chlorobenzilate, 2-chloroethanol, chlorothalonil, cytarabine x HCl, p,p'-DDE, diazinon, 2,6-dichloro-p-phenylenediamine, N,N-diethylthiourea, diglycidylresorcinol ether, 2,4-dimethoxy aniline x HCl, disperse yellow 3, endosulfan, 1,2-epoxyhexadecane, ethyl acrylate, ethyl benzene, ethylene thiourea, F D and C yellow Number 6, furan, heptachlor, isophorone, mercuric chloride, 4,4'-methylenedianiline x 2 HCl, methyl viologen, nickel sulfate x 6H/sub 2/O, 4,4'-oxydianiline, pentachloroethane, piperonyl butoxide, propyl gallate, quinoline, rotenone, 2,4,5,6-tetrachloro-4-nitro-anisole, 1,1,1,2-tetrachloroethane, trichlorfon, 2,4,6-trichlorophenol, 2,4,5-trimethoxybenzaldehyde, 1,1,3-trimethyl-2-thiourea, 1-vinyl-3-cyclopetene dioxide, vinyl toluene, and ziram. The assay was incapable of providing a clear indication of whether some chemicals were mutagens; these benzyl alcohol, 1,4-dichlorobenzene, phenol, succinic acid-2,2-dimethyl hydrazide, and toluene.

  7. Source Term Modeling for Evaluating the Potential Impacts to Groundwater of Fluids Escaping from a Depleted Oil Reservoir Used for Carbon Sequestration

    SciTech Connect (OSTI)

    Cantrell, Kirk J.; Brown, Christopher F.

    2014-06-13T23:59:59.000Z

    In recent years depleted oil reservoirs have received special interest as carbon storage reservoirs because of their potential to offset costs through collaboration with enhanced oil recovery projects. Modeling is currently being conducted to evaluate potential risks to groundwater associated with leakage of fluids from depleted oil reservoirs used for storage of CO2. Modeling results reported here focused on understanding how toxic organic compounds found in oil will distribute between the various phases within a storage reservoir after introduction of CO2, understanding the migration potential of these compounds, and assessing potential groundwater impacts should leakage occur. Two model scenarios were conducted to evaluate how organic components in oil will distribute among the phases of interest (oil, CO2, and brine). The first case consisted of 50 wt.% oil and 50 wt.% water; the second case was 90 wt.% CO2 and 10 wt.% oil. Several key organic compounds were selected for special attention in this study based upon their occurrence in oil at significant concentrations, relative toxicity, or because they can serve as surrogate compounds for other more highly toxic compounds for which required input data are not available. The organic contaminants of interest (COI) selected for this study were benzene, toluene, naphthalene, phenanthrene, and anthracene. Partitioning of organic compounds between crude oil and supercritical CO2 was modeled using the Peng-Robinson equation of state over temperature and pressure conditions that represent the entire subsurface system (from those relevant to deep geologic carbon storage environments to near surface conditions). Results indicate that for a typical set of oil reservoir conditions (75°C, and 21,520 kPa) negligible amounts of the COI dissolve into the aqueous phase. When CO2 is introduced into the reservoir such that the final composition of the reservoir is 90 wt.% CO2 and 10 wt.% oil, a significant fraction of the oil dissolves into the vapor phase. As the vapor phase moves up through the stratigraphic column, pressures and temperatures decrease, resulting in significant condensation of oil components. The heaviest organic components condense early in this process (at higher pressures and temperatures), while the lighter components tend to remain in the vapor phase until much lower pressures and temperatures are reached. Based on the model assumptions, the final concentrations of COI to reach an aquifer at 1,520 kPa and 25°C were quite significant for benzene and toluene, whereas the concentrations of polynuclear aromatic hydrocarbons that reach the aquifer were very small. This work demonstrates a methodology that can provide COI source term concentrations in CO2 leaking from a reservoir and entering an overlying aquifer for use in risk assessments.

  8. This study focuses on the methodology of generating and measuring HONO to study its potential formation from self-cleaning surfaces such as TiO2.

    E-Print Network [OSTI]

    Collins, Gary S.

    and also HONO and toluene and exposed to blacklight illumination. HONO photolyzed to produce the HO radical that oxidizes toluene. A proton-transfer-reactor mass spectrometer was used to measure the decay of toluene and Toluene in Photoreaction Chamber ·Since there is a decrease in the NO2 signal and an increase

  9. Calcium dynamics in astrocytes : from oscillations to Alzheimer's

    E-Print Network [OSTI]

    MacDonald, Christopher Lloyd

    2011-01-01T23:59:59.000Z

    exposed silicon inactivated with silanated PEG groups by the following steps: • Sonicate samples in anhydrous toluene,

  10. Comparison of Advanced Distillation Control Methods, Final Technical Report

    SciTech Connect (OSTI)

    Dr. James B. Riggs

    2000-11-30T23:59:59.000Z

    Detailed dynamic simulations of three industrial distillation columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to evaluate configuration selections for single-ended and dual-composition control, as well as to compare conventional and advanced control approaches. In addition, a simulator of a main fractionator was used to compare the control performance of conventional and advanced control. For each case considered, the controllers were tuned by using setpoint changes and tested using feed composition upsets. Proportional Integral (PI) control performance was used to evaluate the configuration selection problem. For single ended control, the energy balance configuration was found to yield the best performance. For dual composition control, nine configurations were considered. It was determined that the use of dynamic simulations is required in order to identify the optimum configuration from among the nine possible choices. The optimum configurations were used to evaluate the relative control performance of conventional PI controllers, MPC (Model Predictive Control), PMBC (Process Model-Based Control), and ANN (Artificial Neural Networks) control. It was determined that MPC works best when one product is much more important than the other, while PI was superior when both products were equally important. PMBC and ANN were not found to offer significant advantages over PI and MPC. MPC was found to outperform conventional PI control for the main fractionator. MPC was applied to three industrial columns: one at Phillips Petroleum and two at Union Carbide. In each case, MPC was found to significantly outperform PI controls. The major advantage of the MPC controller is its ability to effectively handle a complex set of constraints and control objectives.

  11. Growth and properties of Lithium Salicylate single crystals

    SciTech Connect (OSTI)

    Zaitseva, N; Newby, J; Hull, G; Saw, C; Carman, L; Cherepy, N; Payne, S

    2009-02-13T23:59:59.000Z

    An attractive feature of {sup 6}Li containing fluorescence materials that determines their potential application in radiation detection is the capture reaction with slow ({approx}< 100 keV) neutrons: {sup 6}Li + n = {sup 4}He + {sup 3}H + 4.8MeV. The use of {sup 6}Li-salicylate (LiSal, LiC{sub 6}H{sub 5}O{sub 3}) for thermal neutron detection was previously studied in liquid and polycrystalline scintillators. The studies showed that both liquid and polycrystalline LiSal scintillators could be utilized in pulse shape discrimination (PSD) techniques that enable separation of neutrons from the background gamma radiation. However, it was found that the efficiency of neutron detection using LiSal in liquid solutions was severely limited by its low solubility in commonly used organic solvents like, for example, toluene or xylene. Better results were obtained with neutron detectors containing the compound in its crystalline form, such as pressed pellets, or microscopic-scale (7-14 micron) crystals dispersed in various media. The expectation drown from these studies was that further improvement of pulse height, PSD, and efficiency characteristics could be reached with larger and more transparent LiSal crystals, growth of which has not been reported so far. In this paper, we present the first results on growth and characterization of relatively large, a cm-scale size, single crystals of LiSal with good optical quality. The crystals were grown both from aqueous and anhydrous (methanol) media, mainly for neutron detection studies. However, the results on growth and structural characterization may be interesting for other fields where LiSal, together with other alkali metal salicylates, is used for biological, medical, and chemical (as catalyst) applications.

  12. Ring effect on helical twisting power of optically active mesogenic esters derived from benzene, bicyclo[2.2.2]octane and p-carborane carboxylic

    E-Print Network [OSTI]

    Kaszynski, Piotr

    additive to generate a helical phase is defined as helical twisting power (HTP) or bM (yp21 factors that affect the value of HTP. The emerging picture suggests that the most effective dopants'' for induction of a helical structure, and that higher ``biaxiality'' leads to a higher HTP.11 Further

  13. An evaluation of the Gilian TRACEAIR Organic Vapor Monitoring Diffusive Badge in measuring short-term exposure levels of benzene under field conditions

    E-Print Network [OSTI]

    Pierce, Mark Edward

    1996-01-01T23:59:59.000Z

    that the monitoring system places on the workers who are being sampled. The wide range of drawbacks associated with active sampling necessitated an alternative means of monitoring breathable air in the work environment; namely, a less costly and more user... time-weighted average (TWA) concentrations of airborne organic vapors. This badge was researched, developed, and patented by DuPont under the name of Pro-Tek~ G-AA Organic Vapor Air Monitoring Badge in 1985. Under this trade name, the monitor never...

  14. A study of the condensation of primary, secondary, and tertiary butyl alcohols with benzene in the presence of anhydrous ferric chloride

    E-Print Network [OSTI]

    Dodson, Ralph Jordan

    1939-01-01T23:59:59.000Z

    A PKDT Qt THE COND%SATION QE PRECUT, SSQGNDART~ AND T~ NOTCL ALCOHOLS NITH SEEZEEE IN THE ~E GF ANBIINKU8 mRIQ CHLORIDE Asm 1959 4 et Chea1stxy and 0 A STOSX Gf THE OQtGRWSATIOR Of PRXRARX, SWOORBARX ARRI TCBTXARX WTXL ALQOBOLB WITH 8%%ESSE IR... THS F58XWOR Of AWHXQREUS FERRIC CBLORISR A STUART OF TBR CNRRGATTGR OF PIIRSGKo SROOP~e ARD TRRTZART RDTTL ALCOHOLS RITE ~R ZN TKR FRRSRBCR OP ARBTDROUS PRIBKC OHLORTDR A Theete Parttal Palfileaat cf the ReRNLreewate Ter the aeggso cf Rse4e et...

  15. Electrolytes for power sources

    DOE Patents [OSTI]

    Doddapaneni, N.; Ingersoll, D.

    1995-01-03T23:59:59.000Z

    Electrolytes are disclosed for power sources, particularly alkaline and acidic power sources, comprising benzene polysulfonic acids and benzene polyphosphonic acids or salts of such acids. 7 figures.

  16. Electrolytes for power sources

    DOE Patents [OSTI]

    Doddapaneni, Narayan (Albuquerque, NM); Ingersoll, David (Albuquerque, NM)

    1995-01-01T23:59:59.000Z

    Electrolytes for power sources, particularly alkaline and acidic power sources, comprising benzene polysulfonic acids and benzene polyphosphonic acids or salts of such acids.

  17. Lewis acid–base interactions enhance explosives sensing in silacycle polymers

    E-Print Network [OSTI]

    Sanchez, Jason C.; DiPasquale, Antonio G.; Mrse, Anthony A.; Trogler, William C.

    2009-01-01T23:59:59.000Z

    basic analyte studied was acetonitrile and an associationfor the methyl protons of acetonitrile in benzene-d 6 at 20°a binding event between acetonitrile and the silafluorene

  18. Liquid chromatographic analysis of coal surface properties

    SciTech Connect (OSTI)

    Kwon, K.C.

    1991-01-01T23:59:59.000Z

    The main objectives of this proposed research are to refine further the inverse liquid chromatography technique for the study of surface properties of raw coals, treated coals and coal minerals in water, to evaluate relatively surface properties of raw coals, treated coals and coal minerals by inverse liquid chromatography, and to evaluate floatability of various treated coals in conjunction with surface properties of coals. Alcohols such as methanol, ethanol, isopropanol, isobutanol, tert-butanol, heptanol, 1-hexadecanol, 2-methyl-pentanol, 4-methyl-2-penthanol (methylisobutyl carbinol), n-octanol, s-octanol, and cyclohexanol as probe compounds are utilized to evaluate hydrophilicity of coals and coal minerals. N-alkanes such as hexane, heptane and octane, and stearic acid are employed as probe compounds to evaluate hydrophobicity of coals and coal minerals. Aromatic compounds such as benzene and toluene as probe compounds are used to examine aromaticity of coal surface. Aromatic acids such as o-cresol, m-cresol, p-cresol, phenol and B-naphthol are used to detect aromatic acidic sites of coal surface. Hydrophilicity, hydrophobicity and aromaticity of surfaces for either raw coals or treated coals in water are relatively determined by evaluating both equilibrium physical/chemical adsorption and dynamic adsorption of probe compounds on various raw coals and treated coals to compare affinities of coals for water.

  19. Liquid chromatographic analysis of coal surface properties. Quarterly progress report, September--December 1991

    SciTech Connect (OSTI)

    Kwon, K.C.

    1991-12-31T23:59:59.000Z

    The main objectives of this proposed research are to refine further the inverse liquid chromatography technique for the study of surface properties of raw coals, treated coals and coal minerals in water, to evaluate relatively surface properties of raw coals, treated coals and coal minerals by inverse liquid chromatography, and to evaluate floatability of various treated coals in conjunction with surface properties of coals. Alcohols such as methanol, ethanol, isopropanol, isobutanol, tert-butanol, heptanol, 1-hexadecanol, 2-methyl-pentanol, 4-methyl-2-penthanol (methylisobutyl carbinol), n-octanol, s-octanol, and cyclohexanol as probe compounds are utilized to evaluate hydrophilicity of coals and coal minerals. N-alkanes such as hexane, heptane and octane, and stearic acid are employed as probe compounds to evaluate hydrophobicity of coals and coal minerals. Aromatic compounds such as benzene and toluene as probe compounds are used to examine aromaticity of coal surface. Aromatic acids such as o-cresol, m-cresol, p-cresol, phenol and B-naphthol are used to detect aromatic acidic sites of coal surface. Hydrophilicity, hydrophobicity and aromaticity of surfaces for either raw coals or treated coals in water are relatively determined by evaluating both equilibrium physical/chemical adsorption and dynamic adsorption of probe compounds on various raw coals and treated coals to compare affinities of coals for water.

  20. Vapor Sensing Using Conjugated Molecule-Linked Au Nanoparticles in a Silica Matrix

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Dirk, Shawn M.; Howell, Stephen W.; Price, B. Katherine; Fan, Hongyou; Washburn, Cody; Wheeler, David R.; Tour, James M.; Whiting, Joshua; Simonson, R. Joseph

    2009-01-01T23:59:59.000Z

    Cross-linked assemblies of nanoparticles are of great value as chemiresistor-type sensors. Herein, we report a simple method to fabricate a chemiresistor-type sensor that minimizes the swelling transduction mechanism while optimizing the change in dielectric response. Sensors prepared with this methodology showed enhanced chemoselectivity for phosphonates which are useful surrogates for chemical weapons. Chemoselective sensors were fabricated using an aqueous solution of gold nanoparticles that were then cross-linked in the presence of the silica precursor, tetraethyl orthosilicate with the?-,?-dithiolate (which is derived from the in situ deprotection of 1,4-di(Phenylethynyl-4?,4?-diacetylthio)-benzene (1) with wet triethylamine). The cross-linked nanoparticles and silica matrix were dropmore »coated onto interdigitated electrodes having 8??m spacing. Samples were exposed to a series of analytes including dimethyl methylphosphonate (DMMP), octane, and toluene. A limit of detection was obtained for each analyte. Sensors assembled in this fashion were more sensitive to dimethyl methylphosphonate than to octane by a factor of 1000.« less