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Sample records for hydrocarbon gravimetric method

  1. Downward continuation methods for gravimetric geoid modelling

    NASA Astrophysics Data System (ADS)

    Huang, J.; Véronneau, M.

    2003-04-01

    The determination of a gravimetric geoid model based on the Stokes integral requires that gravity anomalies must be on the geoid and that the anomalous potential must be harmonic above the geoid. To fulfill these requirements, gravity observations (or gravity anomalies) collected on the surface of the Earth need to be reduced to the geoid by a) removing the masses above the geoid and compensating for this removal; and b) continuing the gravity anomalies downward to the geoid. A well-known case is the determination of the Helmert gravity anomalies on the geoid in terms of Helmert's 2nd condensation method (e.g. Martinec et al. 1993). There are two procedures to follow for the evaluation of the Helmert gravity anomalies on the geoid: a) the Helmert gravity anomalies are evaluated on the irregular Earth surface, then are continued downward to the geoid, i.e., masses above the geoid are removed and restored as a condensed layer on the geoid prior to the downward continuation; b) alternatively the refined Bouguer anomalies on the surface of the Earth are downward-continued to the geoid, then the Helmert gravity anomalies are evaluated on the geoid, i.e., the condensed masses are restored after the downward continuation. Both procedures are theoretically equivalent (Huang et al. 2002a). In theory, the inclusion of the downward continuation should improve the geoid regardless of the approach chosen. However, different authors arrive at contradictory conclusions pertaining to its applications (e.g. Pavlis 1998; Ardalan 2000; Jekili and Serpas 2002; Véronneau and Huang 2002). This raises an open question as to how researchers should evaluate the downward continuation in order to improve geoid modeling. In this research, the two procedures described above are used to determine the geoid in Canada. The downward continuations are evaluated using the Poisson and Moritz methods (e.g. Moritz 1980; Sideris 1988; Vanícek et al. 1996; Martinec 1996; Sjöberg 1998; Nahavandchi 2000

  2. Gravimetric capillary method for kinematic viscosity measurements

    NASA Technical Reports Server (NTRS)

    Rosenberger, Franz; Iwan, J.; Alexander, D.; Jin, Wei-Qing

    1992-01-01

    A novel version of the capillary method for viscosity measurements of liquids is presented. Viscosity data can be deduced in a straightforward way from mass transfer data obtained by differential weighing during the gravity-induced flow of the liquid between two cylindrical chambers. Tests of this technique with water, carbon tetrachloride, and ethanol suggest that this arrangement provides an accuracy of about +/- 1 percent. The technique facilitates operation under sealed, isothermal conditions and, thus can readily be applied to reactive and/or high vapor pressure liquids.

  3. Gravimetric method for in vitro calibration of skin hydration measurements.

    PubMed

    Martinsen, Ørjan G; Grimnes, Sverre; Nilsen, Jon K; Tronstad, Christian; Jang, Wooyoung; Kim, Hongsig; Shin, Kunsoo; Naderi, Majid; Thielmann, Frank

    2008-02-01

    A novel method for in vitro calibration of skin hydration measurements is presented. The method combines gravimetric and electrical measurements and reveals an exponential dependency of measured electrical susceptance to absolute water content in the epidermal stratum corneum. The results also show that absorption of water into the stratum corneum exhibits three different phases with significant differences in absorption time constant. These phases probably correspond to bound, loosely bound, and bulk water. PMID:18270010

  4. Gravimetric method for the dynamic measurement of urine flow.

    PubMed

    Steele, J E; Skarlatos, S; Brand, P H; Metting, P J; Britton, S L

    1993-10-01

    The rate of urine formation is a primary index of renal function, but no techniques are currently available to accurately measure low rates of urine flow on a continuous basis, such as are normally found in rats. We developed a gravimetric method for the dynamic measurement of urine flow in anesthetized rats. Catheters were inserted directly into the ureters close to the renal pelves, and a siphon was created to collect all of the urine formed as rapidly as it was produced. Urine flow was determined by measuring the weight of the urine using a direct-reading analytical balance interfaced to a computer. Basal urine flow was measured at 2-sec intervals for 30 to 60 min. The dynamic response of urine flow to a rapid decrease in arterial pressure produced by a bolus intravenous injection of acetylcholine (0.5 micrograms) was also measured. Intrinsic drift, evaporative losses, and the responsiveness of the system to several fixed pump flows in the low physiologic range were evaluated in vitro. The gravimetric method described was able to continuously measure basal urine flows that averaged 37.3 +/- 12.4 microliters/min. Error due to drift and evaporation was negligible, totaling less than 1% of the measured urine flow. Acetylcholine-induced declines in arterial pressure were followed within 8 sec by a decline in urine flow. These data demonstrate that this new gravimetric method provides a simple, inexpensive, dynamic measurement of urine flow in the microliter/min range. PMID:8372099

  5. Comparison of Karl Fischer titrimetric and gravimetric methods for determination of moisture content in BCG vaccine.

    PubMed

    Shi, M; Klegerman, M E; Groves, M J

    1989-01-01

    A model 447 Coulomatic K-F titrimeter was used to determine the water content of seventeen lots of freeze-dried Tice-substrain BCG vaccine. The results were compared with corresponding moisture contents determined by a standard gravimetric method at the time of manufacture. The advantages of the titrimetric method include simplicity, rapidity, convenience, sensitivity, reproducibility and specificity, whereas the gravimetric method is tedious and time-consuming. Although moisture content determined by the K-F titrimeter tended to be higher than that determined by the gravimetric method, the results correlated significantly (r = 0.882, P less than 10(-5]. Alteration of national and international regulations to permit use of the K-F titrimeter is recommended. PMID:2770557

  6. Measuring intestinal fluid transport in vitro: Gravimetric method versus non-absorbable marker.

    PubMed

    Whittamore, Jonathan M; Genz, Janet; Grosell, Martin; Wilson, Rod W

    2016-04-01

    The gut sac is a long-standing, widely used in vitro preparation for studying solute and water transport, and calculation of these fluxes requires an accurate assessment of volume. This is commonly determined gravimetrically by measuring the change in mass over time. While convenient this likely under-estimates actual net water flux (Jv) due to tissue edema. We evaluated whether the popular in vivo volume marker [(14)C]-PEG 4000, offers a more representative measure of Jvin vitro. We directly compared these two methods in five teleost species (toadfish, flounder, rainbow trout, killifish and tilapia). Net fluid absorption by the toadfish intestine based on PEG was significantly higher, by almost 4-fold, compared to gravimetric measurements, compatible with the latter under-estimating Jv. Despite this, PEG proved inconsistent for all of the other species frequently resulting in calculation of net secretion, in contrast to absorption seen gravimetrically. Such poor parallelism could not be explained by the absorption of [(14)C]-PEG (typically <1%). We identified a number of factors impacting the effectiveness of PEG. One was adsorption to the surface of sample tubes. While it was possible to circumvent this using unlabelled PEG 4000, this had a deleterious effect on PEG-based Jv. We also found sequestration of PEG within the intestinal mucus. In conclusion, the short-comings associated with the accurate representation of Jv by gut sac preparations are not overcome by [(14)C]-PEG. The gravimetric method therefore remains the most reliable measure of Jv and we urge caution in the use of PEG as a volume marker. PMID:26794612

  7. Gravimetric water distribution assessment from geoelectrical methods (ERT and EMI) in municipal solid waste landfill.

    PubMed

    Dumont, Gaël; Pilawski, Tamara; Dzaomuho-Lenieregue, Phidias; Hiligsmann, Serge; Delvigne, Frank; Thonart, Philippe; Robert, Tanguy; Nguyen, Frédéric; Hermans, Thomas

    2016-09-01

    The gravimetric water content of the waste material is a key parameter in waste biodegradation. Previous studies suggest a correlation between changes in water content and modification of electrical resistivity. This study, based on field work in Mont-Saint-Guibert landfill (Belgium), aimed, on one hand, at characterizing the relationship between gravimetric water content and electrical resistivity and on the other hand, at assessing geoelectrical methods as tools to characterize the gravimetric water distribution in a landfill. Using excavated waste samples obtained after drilling, we investigated the influences of the temperature, the liquid phase conductivity, the compaction and the water content on the electrical resistivity. Our results demonstrate that Archie's law and Campbell's law accurately describe these relationships in municipal solid waste (MSW). Next, we conducted a geophysical survey in situ using two techniques: borehole electromagnetics (EM) and electrical resistivity tomography (ERT). First, in order to validate the use of EM, EM values obtained in situ were compared to electrical resistivity of excavated waste samples from corresponding depths. The petrophysical laws were used to account for the change of environmental parameters (temperature and compaction). A rather good correlation was obtained between direct measurement on waste samples and borehole electromagnetic data. Second, ERT and EM were used to acquire a spatial distribution of the electrical resistivity. Then, using the petrophysical laws, this information was used to estimate the water content distribution. In summary, our results demonstrate that geoelectrical methods represent a pertinent approach to characterize spatial distribution of water content in municipal landfills when properly interpreted using ground truth data. These methods might therefore prove to be valuable tools in waste biodegradation optimization projects. PMID:26926783

  8. Apparatus and methods for hydrocarbon extraction

    DOEpatents

    Bohnert, George W.; Verhulst, Galen G.

    2016-04-26

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

  9. The Uganda Gravimetric Geoid Model 2014 Computed by The KTH Method

    NASA Astrophysics Data System (ADS)

    Sjöberg, L. E.; Gidudu, A.; Ssengendo, R.

    2015-05-01

    For many developing countries such as Uganda, precise gravimetric geoid determination is hindered by the low quantity and quality of the terrestrial gravity data. With only one gravity data point per 65 km2, gravimetric geoid determination in Uganda appears an impossible task. However, recent advances in geoid modelling techniques coupled with the gravity-field anomalies from the Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) satellite mission have opened new avenues for geoid determination especially for areas with sparse terrestrial gravity. The present study therefore investigates the computation of a gravimetric geoid model overUganda (UGG2014) using the Least Squares Modification of Stokes formula with additive corrections. UGG2014 was derived from sparse terrestrial gravity data from the International Gravimetric Bureau, the 3 arc second SRTM ver4.1 Digital Elevation Model from CGIAR-CSI and the GOCE-only global geopotential model GO_CONS_GCF_2_TIM_R5. To compensate for the missing gravity data in the target area, we used the surface gravity anomalies extracted from the World Gravity Map 2012. Using 10 Global Navigation Satellite System (GNSS)/levelling data points distributed over Uganda, the RMS fit of the gravimetric geoid model before and after a 4-parameter fit is 11 cm and 7 cm respectively. These results show that UGG2014 agrees considerably better with GNSS/levelling than any other recent regional/ global gravimetric geoid model. The results also emphasize the significant contribution of the GOCE satellite mission to the gravity field recovery, especially for areas with very limited terrestrial gravity data.With an RMS of 7 cm, UGG2014 is a significant step forward in the modelling of a "1-cm geoid" over Uganda despite the poor quality and quantity of the terrestrial gravity data used for its computation.

  10. A simple, gravimetric method to quantify inorganic carbon in calcareous soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Total carbon (TC) in calcareous soils has two components: inorganic carbon (IC) as calcite and or dolomite and organic carbon (OC) in the soil organic matter. The IC must be measured and subtracted from TC to obtain OC. Our objective was to develop a simple gravimetric technique to quantify IC. Th...

  11. Method for producing viscous hydrocarbons

    DOEpatents

    Poston, Robert S.

    1982-01-01

    A method for recovering viscous hydrocarbons and synthetic fuels from a subterranean formation by drilling a well bore through the formation and completing the well by cementing a casing means in the upper part of the pay zone. The well is completed as an open hole completion and a superheated thermal vapor stream comprised of steam and combustion gases is injected into the lower part of the pay zone. The combustion gases migrate to the top of the pay zone and form a gas cap which provides formation pressure to produce the viscous hydrocarbons and synthetic fuels.

  12. Catalytic method for synthesizing hydrocarbons

    DOEpatents

    Sapienza, Richard S.; Sansone, Michael J.; Slegeir, William A. R.

    1984-01-01

    A method for synthesizing hydrocarbons from carbon monoxide and hydrogen by contacting said gases with a slurry of a catalyst composed of palladium or platinum and cobalt supported on a solid phase is disclosed. The catalyst is prepared by heating a heterogeneous component of the palladium or platinum deposited on the solid support in a solution of cobalt carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable product fractions even with dilute gaseous reactants.

  13. Catalytic method for synthesizing hydrocarbons

    DOEpatents

    Sapienza, R.S.; Sansone, M.J.; Slegeir, W.A.R.

    A method for synthesizing hydrocarbons from carbon monoxide and hydrogen by contacting said gases with a slurry of a catalyst composed of palladium or platinum and cobalt supported on a solid phase is disclosed. The catalyst is prepared by heating a heterogeneous component of the palladium or platinum deposited on the solid support in a solution of cobalt carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable product fractions even with dilute gaseous reactants.

  14. Investigations on vertical crustal movements in the Venezuelan Andes by gravimetric methods

    NASA Technical Reports Server (NTRS)

    Drewes, H.

    1978-01-01

    A precise gravimetric network has been installed in the Venezuelan Andes to study eventual gravity changes due to vertical tectonic movements. The design and the measurements of the network are described and the accuracy is estimated. In the center of the region a local gravity network has been reobserved three times. The detected variations are discussed. In order to obtain a genuine statement as far as possible about the significance of observed gravity changes, requirements for the procedure of monitoring precise gravity networks are pointed out.

  15. Comparison of the gravimetric, phenol red, and 14C-PEG-3350 methods to determine water absorption in the rat single-pass intestinal perfusion model.

    PubMed

    Sutton, S C; Rinaldi, M T; Vukovinsky, K E

    2001-01-01

    This study was undertaken to determine whether the gravimetric method provided an accurate measure of water flux correction and to compare the gravimetric method with methods that employ nonabsorbed markers (eg, phenol red and 14C-PEG-3350). Phenol red,14C-PEG-3350, and 4-[2-[[2-(6-amino-3-pyridinyl)-2-hydroxyethyl]amino]ethoxy]-, methyl ester, (R)-benzene acetic acid (Compound I) were co-perfused in situ through the jejunum of 9 anesthetized rats (single-pass intestinal perfusion [SPIP]). Water absorption was determined from the phenol red,14C-PEG-3350, and gravimetric methods. The absorption rate constant (ka) for Compound I was calculated. Both phenol red and 14C-PEG-3350 were appreciably absorbed, underestimating the extent of water flux in the SPIP model. The average +/- SD water flux microg/h/cm) for the 3 methods were 68.9 +/- 28.2 (gravimetric), 26.8 +/- 49.2 (phenol red), and 34.9 +/- 21.9 (14C-PEG-3350). The (average +/- SD) ka for Compound I (uncorrected for water flux) was 0.024 +/- 0.005 min(-1). For the corrected, gravimetric method, the average +/- SD was 0.031 +/- 0.001 min(-1). The gravimetric method for correcting water flux was as accurate as the 2 "nonabsorbed" marker methods. PMID:11741276

  16. Determination of total dietary fiber (CODEX definition) by enzymatic-gravimetric method and liquid chromatography: collaborative study.

    PubMed

    McCleary, Barry V; DeVries, Jonathan W; Rader, Jeanne I; Cohen, Gerald; Prosky, Leon; Mugford, David C; Champ, Martine; Okuma, Kazuhiro

    2010-01-01

    A method for the determination of total dietary fiber (TDF), as defined by the CODEX Alimentarius, was validated in foods. Based upon the principles of AOAC Official Methods 985.29, 991.43, 2001.03, and 2002.02, the method quantitates high- and low-molecular-weight dietary fiber (HMWDF and LMWDF, respectively). In 2007, McCleary described a method of extended enzymatic digestion at 37 degrees C to simulate human intestinal digestion followed by gravimetric isolation and quantitation of HMWDF and the use of LC to quantitate low-molecular-weight soluble dietary fiber (LMWSDF). The method thus quantitates the complete range of dietary fiber components from resistant starch (by utilizing the digestion conditions of AOAC Method 2002.02) to digestion resistant oligosaccharides (by incorporating the deionization and LC procedures of AOAC Method 2001.03). The method was evaluated through an AOAC collaborative study. Eighteen laboratories participated with 16 laboratories returning valid assay data for 16 test portions (eight blind duplicates) consisting of samples with a range of traditional dietary fiber, resistant starch, and nondigestible oligosaccharides. The dietary fiber content of the eight test pairs ranged from 11.57 to 47.83%. Digestion of samples under the conditions of AOAC Method 2002.02 followed by the isolation and gravimetric procedures of AOAC Methods 985.29 and 991.43 results in quantitation of HMWDF. The filtrate from the quantitation of HMWDF is concentrated, deionized, concentrated again, and analyzed by LC to determine the LMWSDF, i.e., all nondigestible oligosaccharides of degree of polymerization > or =3. TDF is calculated as the sum of HMWDF and LMWSDF. Repeatability standard deviations (Sr) ranged from 0.41 to 1.43, and reproducibility standard deviations (S(R)) ranged from 1.18 to 5.44. These results are comparable to other official dietary fiber methods, and the method is recommended for adoption as Official First Action. PMID:20334184

  17. Determination of insoluble, soluble, and total dietary fiber (CODEX definition) by enzymatic-gravimetric method and liquid chromatography: collaborative study.

    PubMed

    McCleary, Barry V; DeVries, Jonathan W; Rader, Jeanne I; Cohen, Gerald; Prosky, Leon; Mugford, David C; Okuma, Kazuhiro

    2012-01-01

    A method for the determination of insoluble (IDF), soluble (SDF), and total dietary fiber (TDF), as defined by the CODEX Alimentarius, was validated in foods. Based upon the principles of AOAC Official Methods 985.29, 991.43, 2001.03, and 2002.02, the method quantitates water-insoluble and water-soluble dietary fiber. This method extends the capabilities of the previously adopted AOAC Official Method 2009.01, Total Dietary Fiber in Foods, Enzymatic-Gravimetric-Liquid Chromatographic Method, applicable to plant material, foods, and food ingredients consistent with CODEX Definition 2009, including naturally occurring, isolated, modified, and synthetic polymers meeting that definition. The method was evaluated through an AOAC/AACC collaborative study. Twenty-two laboratories participated, with 19 laboratories returning valid assay data for 16 test portions (eight blind duplicates) consisting of samples with a range of traditional dietary fiber, resistant starch, and nondigestible oligosaccharides. The dietary fiber content of the eight test pairs ranged from 10.45 to 29.90%. Digestion of samples under the conditions of AOAC 2002.02 followed by the isolation, fractionation, and gravimetric procedures of AOAC 985.29 (and its extensions 991.42 and 993.19) and 991.43 results in quantitation of IDF and soluble dietary fiber that precipitates (SDFP). The filtrate from the quantitation of water-alcohol-insoluble dietary fiber is concentrated, deionized, concentrated again, and analyzed by LC to determine the SDF that remains soluble (SDFS), i.e., all dietary fiber polymers of degree of polymerization = 3 and higher, consisting primarily, but not exclusively, of oligosaccharides. SDF is calculated as the sum of SDFP and SDFS. TDF is calculated as the sum of IDF and SDF. The within-laboratory variability, repeatability SD (Sr), for IDF ranged from 0.13 to 0.71, and the between-laboratory variability, reproducibility SD (SR), for IDF ranged from 0.42 to 2.24. The within

  18. Quantitative Hydrocarbon Energies from the PMO Method.

    ERIC Educational Resources Information Center

    Cooper, Charles F.

    1979-01-01

    Details a procedure for accurately calculating the quantum mechanical energies of hydrocarbons using the perturbational molecular orbital (PMO) method, which does not require the use of a computer. (BT)

  19. Method for determining permeability in hydrocarbon wells

    SciTech Connect

    Boone, D.E.

    1990-10-09

    This patent describes a method of determining at the earth's surface the permeability of a subsurface earth formation having a known nominal hydrocarbon pore saturation value. The formation is tranversed by a borehole resulting from drilling with a drill bit.

  20. Economical difference methods for solving direct problems in gravimetric and magnetic prospecting

    NASA Astrophysics Data System (ADS)

    Vabishchevich, P. N.; Pulatov, P. A.

    1984-05-01

    A method is proposed for the solution of direct problems in gravimetry and magnetometry based on solution of Dirichlet difference problems for the Poisson equation in the selected region. An effective computation scheme is developed for solution of direct problems for bodies of an arbitrary configuration and variable density. The algorithm, given here in detail, was tested in solution of a number of model problems. Although the algorithm is written up for a plane (two dimensional) problem, it could easily be adapted to a three dimensional case, although the solution of the latter requires a far larger computer memory. The merits of the algorithm include the following: (1) possibility of finding both external and internal fields; (2) possibility of aolution of direct problems with arbitrary laws of density distribution in regions of arbitrary configuration. Accordingly, it is suggested that the proposed algorithm will have a broad field of applicability, particularly in the interpretation of data from surface and borehole (mine) observations in ore geophysics.

  1. Geochemical methods of prospecting for hydrocarbons

    SciTech Connect

    Duchscherer, W. Jr.

    1980-12-01

    Because the commonly used reflection-seismograph exploration technique misses many marginal low-relief structural prospects and regardless of its electronic computer sophistication, overlooks almost all stratigraphic traps, the hydrocarbon exploration industry should take a look at geochemical prospecting methods, which detect geochemical anomalies in the near-surface soils by measuring the thermal dissociation of the soil carbonates that are found overlying hydrocarbon accumulations. To promote understanding of such prospecting techniques, Geochemical Surveys reviews the methods used, the soil-alteration patterns, the lateral and vertical migration of hydrocarbon gases, the halo phenomenon (a ring or annual anomaly), the geochemical modification of sediments, and the data-interpretation and exploration procedures involved in a carbonate ..delta.. C analysis, which measures the residual, stable, cumulative effect of hydrocarbon migration.

  2. Methods for dispersing hydrocarbons using autoclaved bacteria

    DOEpatents

    Tyndall, Richard L.

    1996-01-01

    A method of dispersing a hydrocarbon includes the steps: providing a bacterium selected from the following group: ATCC 85527, ATCC 75529, and ATCC 55638, a mutant of any one of these bacteria possessing all the identifying characteristics of any one of these bacteria, and mixtures thereof; autoclaving the bacterium to derive a dispersant solution therefrom; and contacting the dispersant solution with a hydrocarbon to disperse the hydrocarbon. Moreover, a method for preparing a dispersant solution includes the following steps: providing a bacterium selected from the following group: ATCC 75527, ATCC 75529, and ATCC 55638, a mutant of any one of these bacteria possessing all the identifying characteristics of any one of these bacteria, and mixtures thereof; and autoclaving the bacterium to derive a dispersant solution therefrom.

  3. Methods for dispersing hydrocarbons using autoclaved bacteria

    DOEpatents

    Tyndall, R.L.

    1996-11-26

    A method of dispersing a hydrocarbon includes the following steps: providing a bacterium selected from the following group: ATCC 85527, ATCC 75529, and ATCC 55638, a mutant of any one of these bacteria possessing all the identifying characteristics of any one of these bacteria, and mixtures; autoclaving the bacterium to derive a dispersant solution; and contacting the dispersant solution with a hydrocarbon to disperse the hydrocarbon. Moreover, a method for preparing a dispersant solution includes the following steps: providing a bacterium selected from the following group: ATCC 75527, ATCC 75529, and ATCC 55638, a mutant of any one of these bacteria possessing all the identifying characteristics of any one of these bacteria, and mixtures; and autoclaving the bacterium to derive a dispersant solution.

  4. Method for collecting and analyzing hydrocarbons

    SciTech Connect

    Ouellette, G.P.; Larter, S.R.; Fox, J.R.

    1988-12-20

    This patent describes a method for separating and collecting hydrocarbons which include methane from a gas obtained from the vicinity of an earth formation and obtaining information from such a gas which is useful in predicting the hydrocarbon potential of such an earth formation, the method comprising the steps of: obtaining a sample of a gas from the vicinity of an earth formation, the sample including methane; removing any water, carbon dioxide, and carbon monoxide from the sample and passing the sample through a cryogenic trap to separate and collect any interfering gases and hydrocarbons having at least two carbon atoms from the sample into the cryogenic trap. The removing and passing steps produce a first gas which contains the methane from the sample but which is free of water, carbon dioxide, carbon monoxide, interfering gases, and hydrocarbons having at least two carbon atoms; converting the methane in the first gas to form a condensed carbon dioxide sample; carrying out the removing, passing, and converting steps under a continuous subatmospheric pressure in such a manner as to prevent condensation of any oxygen in the cryogenic trap and to prevent any atmospheric carbon dioxide from entering into the sample, the first gas, the cryogenic trap, and the condensed carbon dioxide sample; determining the stable carbon isotope ratio of the condensed carbon dioxide sample which can be then be used to predict the hydrocarbon potential of the earth formation.

  5. Method of dispersing a hydrocarbon using bacteria

    DOEpatents

    Tyndall, R.L.

    1996-09-24

    A new protozoan derived microbial consortia and method for their isolation are provided. The isolated consortia and bacteria are useful for treating wastes such as trichloroethylene and trinitrotoluene. The isolated consortia, bacteria, and dispersants are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.

  6. Method of dispersing a hydrocarbon using bacteria

    DOEpatents

    Tyndall, Richard L.

    1996-01-01

    New protozoan derived microbial consortia and method for their isolation are provided. Consortia and bacteria isolated therefrom are useful for treating wastes such as trichloroethylene and trinitrotoluene. Consortia, bacteria isolated therefrom, and dispersants isolated therefrom are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.

  7. Method and apparatus for synthesizing hydrocarbons

    DOEpatents

    Colmenares, C.A.; Somorjai, G.A.; Maj, J.J.

    1983-06-21

    A method and apparatus for synthesizing a mixture of hydrocarbons having five carbons or less is disclosed. An equal molar ratio of CO and H/sub 2/ gases is caused to pass through a ThO/sub 2/ catalyst having a surface area of about 80 to 125 m/sup 2//g. The catalyst further includes Na present as a substitutional cation in an amount of about 5 to 10 atom %. At a temperature of about 340 to 360/sup 0/C, and at pressures of about 20 to 50 atm, CH/sub 3/OH is produced in an amount of about 90 wt % of the total hydrocarbon mixture, and comprised 1 mole % of the effluent gas.

  8. Conversion method for gas streams containing hydrocarbons

    DOEpatents

    Mallinson, Richard G.; Lobban, Lance; Liu, Chang-jun

    2000-01-01

    An apparatus and a method of using the apparatus are provided for converting a gas stream containing hydrocarbons to a reaction product containing effluent molecules having at least one carbon atom, having at least one interior surface and at least one exterior surface, a first electrode and a second electrode with the first and second electrodes being selectively movable in relation to each other and positioned within the housing so as to be spatially disposed a predetermined distance from each other, a plasma discharge generator between the first and second electrodes, gas stream introducer and a collector for collecting the reaction product effluent produced by the reaction of the gas stream containing hydrocarbons with the plasma discharge between the first and second electrodes.

  9. The gravimetric geodesy investigation

    NASA Technical Reports Server (NTRS)

    Siry, J. W.

    1971-01-01

    The Gravimetric Geodesy Investigation which will utilize altimeter and satellite-to-satellite tracking data from GEOS-C, ATS-F, and other spacecraft as appropriate to improve our knowledge of the earth's gravitational field is discussed. This investigation is interrelated with the study of oceanographic phenomena such as those associated with tides and currents, hence the latter are considered together with gravitational effects in the analysis of the data. The oceanographic effects, each of the order of a meter or two in amplitude and with still smaller uncertainties does not seriously hamper the altimeter gravimetric studies at the five meter level. Laser and satellite-to-satellite tracking data, when combined with the altimeter results, should provide the basis for such studies over wide areas of the ocean surface. Laser and conventional geodetic tracking data from ISAGEX and succeeding campaigns will provide a valuable framework for these analyses.

  10. Method and apparatus for low temperature destruction of halogenated hydrocarbons

    DOEpatents

    Reagen, William Kevin; Janikowski, Stuart Kevin

    1999-01-01

    A method and apparatus for decomposing halogenated hydrocarbons are provided. The halogenated hydrocarbon is mixed with solvating agents and maintained in a predetermined atmosphere and at a predetermined temperature. The mixture is contacted with recyclable reactive material for chemically reacting with the recyclable material to create dehalogenated hydrocarbons and halogenated inorganic compounds. A feature of the invention is that the process enables low temperature destruction of halogenated hydrocarbons.

  11. Method and apparatus for synthesizing hydrocarbons

    DOEpatents

    Colmenares, C.A.; Somorjai, G.A.; Maj, J.J.

    1985-04-16

    A method and apparatus for synthesizing a mixture of aliphatic alcohols having five carbons or less is disclosed. An equal molar ratio of CO and H/sub 2/ gases is caused to pass through a ThO/sub 2/ catalyst having a surface area of about 80 to 125 m/sup 2//g. The catalyst further optionally includes Na ions present as substitutional cations in an amount of about 5 to 10 atom %. At a temperature of about 570 to 630/sup 0/K, and at pressures of about 20 to 50 atm, methanol and isobutanol are the predominant products and are produced in amounts of about 90 wt % of the total hydrocarbon mixture. 6 figs.

  12. Spatial distribution of soil moisture obtained from gravimetric and TDR methods for SMOS validation, at the Polesie test site SVRT 3275, in Poland

    NASA Astrophysics Data System (ADS)

    Usowicz, B.; Marczewski, W.; Lipiec, J.; Usowicz, J. B.; Sokolowska, Z.; Dabkowska-Naskret, H.; Hajnos, M.; Lukowski, M. I.

    2009-04-01

    The purpose is obtaining trustful ground based measurement data of SM (Soil Moisture) for validating SMOS, respectively to spatial and temporal distribution and variations. A use of Time Domain Reflectometric (TDR) method is fast, simple and less destructive, to the soil matter, than a usual standard gravimetric method. TDR tools operate efficiently, enable nearly instant measurements, and allow on collecting many measurements from numerous sites, even when operated manually in short time intervals. The method enables also very frequent sampling of SM at few selected fixed sites, when long terms of temporal variations are needed. In effect one obtains reasonably large data base for determining spatial and temporal distributions of SM. The study is devoted to determining a plan on collecting TDR data, in the scales of small and large field areas, and checking their relevance to those available from gravimetric methods. Finally, the ground based SM distributions are needed for validating other SM distributions, available remotely in larger scales, from the satellite data of ENVISAT-ASAR, and from SMOS (Soil Moisture and Ocean Salinity Mission) when it becomes operational. The ground based evaluations are served mainly by geo-statistical analysis. The space borne estimations are retrieved by image processing and physical models, proper to relevant Remote Sensing (RS) instruments on the orbit. Finally, validation must engage again the geo-statistical evaluations, to assess the agreement between direct and remote sensing means, and provide a measure of trust for extending the limited scales of the ground based data, on concluding the agreement in scales proper to the satellite data. The study is focused mainly on trustful evaluating data from the ground, provided independently on satellite data sources. SM ground based data are collected permanently at 2 selected tests sites, and temporary in areas around the tests sites, in one day sessions, repeated several times per

  13. Chromatographic method for determining fouling tendency of liquid hydrocarbons

    SciTech Connect

    Dickakian, G.B.

    1988-06-21

    A method is described for determining the tendency of a liquid hydrocarbon stream to foul equipment comprising the steps of: (a) depositing a sample of liquid hydrocarbon from a liquid hydrocarbon stream onto a surface of a thin film in the presence of an asphaltene antisolvent, wherein the thin film is made up of a chromatographic separation material; (b) letting the sample of liquid hydrocarbon migrate radially outward within the film for sufficient time so that hydrocarbon compatible fractions in the sample separate from any hydrocarbon-incompatible asphaltenes in the sample, wherein the hydrocarbon compatible fractions form a matrix portion in the film and any hydrocarbon-incompatible asphaltenes form a dark ring within the matrix portion and wherein any ring formed is disposed within a central region of the matrix portion and is distinguished from the matrix portion by a dark area having a boundary with respect to a lighter area; and (c) determining the tendency of the liquid hydrocarbon stream to fuel equipment by comparing the matrix portion with any dark ring formed from any hydrocarbon-incompatible asphaltenes in the sample, wherein the area and intensity of any ring formed in relation to the matrix portion provides an indication of the tendency of the liquid hydrocarbon stream to foul equipment.

  14. Methods for natural gas and heavy hydrocarbon co-conversion

    DOEpatents

    Kong, Peter C.; Nelson, Lee O.; Detering, Brent A.

    2009-02-24

    A reactor for reactive co-conversion of heavy hydrocarbons and hydrocarbon gases and includes a dielectric barrier discharge plasma cell having a pair of electrodes separated by a dielectric material and passageway therebetween. An inlet is provided for feeding heavy hydrocarbons and other reactive materials to the passageway of the discharge plasma cell, and an outlet is provided for discharging reaction products from the reactor. A packed bed catalyst may optionally be used in the reactor to increase efficiency of conversion. The reactor can be modified to allow use of a variety of light sources for providing ultraviolet light within the discharge plasma cell. Methods for upgrading heavy hydrocarbons are also disclosed.

  15. Method of increasing the efficiency of a liquid hydrocarbon fuel

    SciTech Connect

    Sakata, H.

    1986-02-11

    This patent describes a method of increasing the efficiency of a liquid hydrocarbon fuel. The method consists of the steps of repeatedly and alternately subjecting the fuel to a magnetic field and to radioactive rays.

  16. Comparison of a direct-reading device to gravimetric methods for evaluating organic dust aerosols in an enclosed swine production environment.

    PubMed

    Taylor, C D; Reynolds, S J

    2001-01-01

    The production of livestock in enclosed facilities has become an accepted practice, driven by the need for increased efficiency. Exposure to organic dusts, containing various bioactive components, has been identified an important risk factor for the high rate of lung disease found among workers in these environments. Assessment of organic dust exposure requires technical skills and instrumentation not readily available to most agricultural enterprises. Development of a simple, cost-effective method for measuring organic dust levels would be useful in evaluating and controlling exposures in these environments. The objective of this study was to evaluate the usefulness of the direct reading MIE PDM-3 Miniram for estimating organic dust concentrations in enclosed swine production facilities. Responses from the MIE PDM-3 Miniram were compared to gravimetric methods for total and inhalable dust. Total dust determinations were conducted in accordance with the National Institute for Occupational Safety and Health (NIOSH) method 0500. Inhalable particulate mass (IPM) sampling was conducted using SKC brand IOM (Institute of Occupational Medicine) sampling cassettes, which meet the American Conference of Governmental Industrial Hygienists ACGIH criteria for inhalable dust sampling. This study design also allowed for the comparison of traditional total dust method to the IPM method, in collecting organic dusts in an agricultural setting. Fifteen sets of side-by-side samples (Miniram, total dust, and IPM) were collected over a period of six months in a swine confinement building. There were statistically significant differences in the results provided by the three sampling methods. Measurements for inhalable dust exceeded those for total dust in eleven of fifteen samples. The Miniram time-weighted average (TWA) response to the organic dust was always the lower of the three methods. A high degree of correlation was found among all three methods. The Miniram performed well under

  17. Substantially self-powered method and apparatus for recovering hydrocarbons from hydrocarbon-containing solid hydrates

    DOEpatents

    Elliott, G.R.B.; Barraclough, B.L.; Vanderborgh, N.E.

    1981-02-19

    A method and apparatus are provided for producing gaseous hydrocarbons from formations comprising solid hydrocarbon hydrates located under either a body of land or a body of water. The vast natural resources of such hydrocarbon hydrates can thus now be economically mined. Relatively warm brine or water is brought down from an elevation above that of the hydrates through a portion of the apparatus, and passes in contact with the hydrates, thus melting them. The liquid then continues up another portion of the apparatus carrying entrained hydrocarbon vapors in the form of bubbles, which can easily be separated from the liquid. After a short startup procedure, the process and apparatus are substantially self-powered.

  18. Substantially self-powered method and apparatus for recovering hydrocarbons from hydrocarbon-containing solid hydrates

    DOEpatents

    Elliott, Guy R. B.; Barraclough, Bruce L.; Vanderborgh, Nicholas E.

    1983-01-01

    A method and apparatus are provided for producing gaseous hydrocarbons from formations comprising solid hydrocarbon hydrates located under either a body of land or a body of water. The vast natural resources of such hydrocarbon hydrates can thus now be economically mined. Relatively warm brine or water is brought down from an elevation above that of the hydrates through a portion of the apparatus and passes in contact with the hydrates, thus melting them. The liquid then continues up another portion of the apparatus, carrying entrained hydrocarbon vapors in the form of bubbles, which can easily be separated from the liquid. After a short startup procedure, the process and apparatus are substantially self-powered.

  19. Catalysts for converting syngas into liquid hydrocarbons and methods thereof

    DOEpatents

    Yu, Fei; Yan, Qiangu; Batchelor, William

    2016-03-15

    The presently-disclosed subject matter includes methods for producing liquid hydrocarbons from syngas. In some embodiments the syngas is obtained from biomass and/or comprises a relatively high amount of nitrogen and/or carbon dioxide. In some embodiments the present methods can convert syngas into liquid hydrocarbons through a one-stage process. Also provided are catalysts for producing liquid hydrocarbons from syngas, wherein the catalysts include a base material, a transition metal, and a promoter. In some embodiments the base material includes a zeolite-iron material or a cobalt-molybdenum carbide material. In still further embodiments the promoter can include an alkali metal.

  20. Method and apparatus for detecting gem-polyhalogenated hydrocarbons

    DOEpatents

    Anderson, deceased, William G.; Anderson, legal representative, Johanna S.

    1990-01-01

    A method and optrode for detecting gem polyhalogenated hydrocarbons in a sample fluid based on a single phase Fujiwara reaction as provided. The method comprises contacting a reaction mixture with a sample fluid which contains the gem-polyhalogenated hydrocarbons. The reaction mixture comprises an aqueous solution of pyridine or derivative thereof and a hindered nitrogen base. Upon contact a fluorescent and/or chromgenic reaction product forms whose fluorescence and/or absorbance is related to the concentration of gem-polyhalogenated hydrocarbons in the sample fluid.

  1. Method for making hydrogen rich gas from hydrocarbon fuel

    DOEpatents

    Krumpelt, M.; Ahmed, S.; Kumar, R.; Doshi, R.

    1999-07-27

    A method of forming a hydrogen rich gas from a source of hydrocarbon fuel in which the hydrocarbon fuel contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion at a temperature not less than about 400 C for a time sufficient to generate the hydrogen rich gas while maintaining CO content less than about 5 volume percent. There is also disclosed a method of forming partially oxidized hydrocarbons from ethanes in which ethane gas contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion for a time and at a temperature sufficient to form an oxide. 4 figs.

  2. Method for making hydrogen rich gas from hydrocarbon fuel

    DOEpatents

    Krumpelt, Michael; Ahmed, Shabbir; Kumar, Romesh; Doshi, Rajiv

    1999-01-01

    A method of forming a hydrogen rich gas from a source of hydrocarbon fuel in which the hydrocarbon fuel contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion at a temperature not less than about 400.degree. C. for a time sufficient to generate the hydrogen rich gas while maintaining CO content less than about 5 volume percent. There is also disclosed a method of forming partially oxidized hydrocarbons from ethanes in which ethane gas contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion for a time and at a temperature sufficient to form an oxide.

  3. Hydrocarbons from plants: Analytical methods and observations

    SciTech Connect

    Calvin, Melvin

    1980-11-01

    We have suggested that certain plants rich in hydrocarbon-like materials might be cultivated for renewable photosynthetic products. Two species were selected for experimental plantations: Euphorbia lathyris, an annual from seed and Euphorbia tirucalli, a perennial from cuttings, The yield from each species is over 10 barrels of oil/acre/year without genetic or agronomic improvement. In addition to plants, there are trees, such as species of Copaifera in Brazil and other tropical areas, which produce a diesel-like oil upon tapping. Each tree produces approximately 40 liters of hydrocarbon per year, and this material can be used directly by a diesel-powered car. Further efforts to develop plants as alternate energy sources are underway, as well as a continuing search for additional plant species throughout the world which have a similar capability.

  4. Hydrocarbon synthesis catalyst and method of preparation

    DOEpatents

    Sapienza, R.S.; Sansone, M.J.; Slegeir, W.A.R.

    1983-08-02

    A catalyst for the synthesis of hydrocarbons from carbon monoxide and hydrogen composed of palladium or platinum and cobalt supported on a solid phase is disclosed. The catalyst is prepared by heating a heterogeneous component of the palladium or platinum deposited on the solid support in a solution of cobalt carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable product fractions even with dilute gaseous reactants. The catalyst is preferably used in dilute slurry form, which is desirable from a heat transfer standpoint. 9 figs.

  5. Hydrocarbon synthesis catalyst and method of preparation

    DOEpatents

    Sapienza, Richard S.; Sansone, Michael J.; Slegeir, William A. R.

    1983-08-02

    A catalyst for the synthesis of hydrocarbons from carbon monoxide and hydrogen composed of palladium or platinum and cobalt supported on a solid phase is disclosed. The catalyst is prepared by heating a heterogeneous component of the palladium or platinum deposited on the solid support in a solution of cobalt carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable product fractions even with dilute gaseous reactants. The catalyst is preferably used in dilute slurry form, which is desirable from a heat transfer standpoint.

  6. Method for coupling a hydrocarbon containing molecular species

    SciTech Connect

    Lingwood, C.A.

    1986-07-01

    A method is described of covalently coupling two molecular species comprising: (a) combining (i) a first molecular species having a functionality reactive with hydrocarbon when photo-activated; and (ii) a solution of at least one, hydrocarbon containing, molecular species in the absence of photo-radiation to which the functionality is sensitive; (b) removing the solvent; (c) irradiating the mixture with photo-radiation to which the functionality is photosensitive.

  7. Method and apparatus for detecting halogenated hydrocarbons

    DOEpatents

    Monagle, Matthew; Coogan, John J.

    1997-01-01

    A halogenated hydrocarbon (HHC) detector is formed from a silent discharge (also called a dielectric barrier discharge) plasma generator. A silent discharge plasma device receives a gas sample that may contain one or more HHCs and produces free radicals and excited electrons for oxidizing the HHCs in the gas sample to produce water, carbon dioxide, and an acid including halogens in the HHCs. A detector is used to sensitively detect the presence of the acid. A conductivity cell detector combines the oxidation products with a solvent where dissociation of the acid increases the conductivity of the solvent. The conductivity cell output signal is then functionally related to the presence of HHCs in the gas sample. Other detectors include electrochemical cells, infrared spectrometers, and negative ion mobility spectrometers.

  8. Gravimetric gas determinations for volume calibrations

    SciTech Connect

    Gibbs, P.W.

    1991-01-01

    Gravimetric measurement of gases is one of the methods available for calibrating gas volumes. By inputting a known quantity of gas and measuring the resulting pressure and temperature, the system volume can be calculated using gas law principles. Historically, this method has been less accurate due to the difficulty in the mass determination. This difficulty comes from several sources. Two examples are the large tare weight of the gas container relative to the weight of gas and the external volume of the gas container relative to the standards. The application of a gravimetric gas determination to tank volume calibrations at the Savannah River Site is discussed. Mass determinations on a 25,000 gram gas container were such that a 1500 gram quantity of gas was routinely determined to within {plus minus}0.2 gram at the 99% confidence level. The weighing design and the methods used to address the difficulties of the mass determination are detailed.

  9. Gravimetric gas determinations for volume calibrations

    SciTech Connect

    Gibbs, P.W.

    1991-12-31

    Gravimetric measurement of gases is one of the methods available for calibrating gas volumes. By inputting a known quantity of gas and measuring the resulting pressure and temperature, the system volume can be calculated using gas law principles. Historically, this method has been less accurate due to the difficulty in the mass determination. This difficulty comes from several sources. Two examples are the large tare weight of the gas container relative to the weight of gas and the external volume of the gas container relative to the standards. The application of a gravimetric gas determination to tank volume calibrations at the Savannah River Site is discussed. Mass determinations on a 25,000 gram gas container were such that a 1500 gram quantity of gas was routinely determined to within {plus_minus}0.2 gram at the 99% confidence level. The weighing design and the methods used to address the difficulties of the mass determination are detailed.

  10. Method for recovering light hydrocarbons from coal agglomerates

    DOEpatents

    Huettenhain, Horst; Benz, August D.; Getsoian, John

    1991-01-01

    A method and apparatus for removing light hydrocarbons, such as heptane, from coal agglomerates includes an enclosed chamber having a substantially horizontal perforate surface therein. The coal agglomerates are introduced into a water bath within the chamber. The agglomerates are advanced over the surface while steam is substantially continuously introduced through the surface into the water bath. Steam heats the water and causes volatilization of the light hydrocarbons, which may be collected from the overhead of the chamber. The resulting agglomerates may be collected at the opposite end from the surface and subjected to final draining processes prior to transportation or use.

  11. Method for determining processability of a hydrocarbon containing feedstock

    SciTech Connect

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

    2013-09-10

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

  12. Method and apparatus for producing oxygenates from hydrocarbons

    DOEpatents

    Kong, Peter C.; Lessing, Paul A.

    1995-01-01

    A chemical reactor for oxygenating hydrocarbons includes: a) a dielectric barrier discharge plasma cell, the plasma cell comprising a pair of electrodes having a dielectric material and void therebetween, the plasma cell comprising a hydrocarbon gas inlet feeding to the void; b) a solid oxide electrochemical cell, the electrochemical cell comprising a solid oxide electrolyte positioned between a porous cathode and a porous anode, an oxygen containing gas inlet stream feeding to the porous cathode side of the electrochemical cell; c) a first gas passageway feeding from the void to the anode side of the electrochemical cell; and d) a gas outlet feeding from the anode side of the electrochemical cell to expel reaction products from the chemical reactor. A method of oxygenating hydrocarbons is also disclosed.

  13. Method and apparatus for producing oxygenates from hydrocarbons

    DOEpatents

    Kong, P.C.; Lessing, P.A.

    1995-06-27

    A chemical reactor for oxygenating hydrocarbons includes: (a) a dielectric barrier discharge plasma cell, the plasma cell comprising a pair of electrodes having a dielectric material and void therebetween, the plasma cell comprising a hydrocarbon gas inlet feeding to the void; (b) a solid oxide electrochemical cell, the electrochemical cell comprising a solid oxide electrolyte positioned between a porous cathode and a porous anode, an oxygen containing gas inlet stream feeding to the porous cathode side of the electrochemical cell; (c) a first gas passageway feeding from the void to the anode side of the electrochemical cell; and (d) a gas outlet feeding from the anode side of the electrochemical cell to expel reaction products from the chemical reactor. A method of oxygenating hydrocarbons is also disclosed. 4 figs.

  14. Means and method for producing hydrocarbons from an earth formation during the RF retorting of a hydrocarbon stratum

    SciTech Connect

    Savage, K.D.

    1987-01-27

    A method is described for obtaining hydrocarbon liquid from a hydrocarbon strata of an earth formation traversed by a borehole, the hydrocarbon strata being subjected to RF electromagnetic energy retorting, comprising the steps of: (a) forming metal tubing so as to create a tubing coil having a predetermined electrical inductance, (b) connecting straight metal tubing with the metal tubing of step (a) so that the tubing of steps (a) and (b) form a production string, and (c) pumping the hydrocarbon liquid from the borehole through the production string to the surface of the earth formation.

  15. Method of hydrorefining asphaltenic hydrocarbon feedstocks

    SciTech Connect

    Gleim, W.K.

    1981-07-21

    A method of hydrorefining an asphaltenic charge stock is described which comprises effecting said reaction utilizing a titanium sulfide catalyst in a hydrogen sulfide-containing H2 atmosphere. The catalyst may be employed in slurry form or composited with a high surface area coke support. Preferably chloride is also present in the catalyst. The hydrogen sulfide suitably is present in the gas phase in an amount of from about 10 to about 25 mol percent based on the moles of H2 present.

  16. Method for production of hydrocarbons from hydrates

    DOEpatents

    McGuire, Patrick L.

    1984-01-01

    A method of recovering natural gas entrapped in frozen subsurface gas hydrate formations in arctic regions. A hot supersaturated solution of CaCl.sub.2 or CaBr.sub.2, or a mixture thereof, is pumped under pressure down a wellbore and into a subsurface hydrate formation so as to hydrostatically fracture the formation. The CaCl.sub.2 /CaBr.sub.2 solution dissolves the solid hydrates and thereby releases the gas entrapped therein. Additionally, the solution contains a polymeric viscosifier, which operates to maintain in suspension finely divided crystalline CaCl.sub.2 /CaBr.sub.2 that precipitates from the supersaturated solution as it is cooled during injection into the formation.

  17. Active geophysical monitoring of hydrocarbon reservoirs using EM methods

    NASA Astrophysics Data System (ADS)

    Gribenko, A.; Black, N.; Zhdanov, M. S.

    2008-12-01

    Marine controlled-source electromagnetic (MCSEM) technology has been successfully established as an effective tool for offshore hydrocarbon (HC) exploration. In this paper we consider another application of the MCSEM method for HC reservoir monitoring. We demonstrate that EM methods can be successfully used for the monitoring of producing wells in connection with the enhanced recovery of hydrocarbons. We have developed a new powerful EM modeling technique based on the integral equation method with an inhomogeneous background conductivity (IE IBC). This new method and the corresponding computer software make it possible to model the EM response over a realistic complex model of a sea-bottom HC reservoir. The numerical modeling results demonstrate that the MCSEM method has the ability to map changes in resistivity caused by the production of hydrocarbons over time. In addition, the EM data help to visualize the changes in the location of the oil-water contact within the reservoir. This result opens the possibility for practical application of the EM method in HC reservoir monitoring.

  18. EPA (ENVIONMENTAL PROTECTION AGENCY) METHOD STUDY 20, METHOD 610--PNA'S (POLYNUCLEAR AROMATIC HYDROCARBONS)

    EPA Science Inventory

    Sixteen laboratories participated in an interlaboratory study conducted to provide precision and accuracy statements for the proposed EPA Method 610 for 16 selected polynuclear aromatic hydrocarbons(PNA's) which may be present in municipal and industrial aqueous discharges. Metho...

  19. EPA (ENVIRONMENTAL PROTECTION AGENCY) METHOD STUDY 22. METHOD 612-CHLORINATED HYDROCARBONS

    EPA Science Inventory

    An interlaboratory study in which 20 laboratories participated was conducted to provide precision and accuracy statements for the proposed EPA Method 612 - Chlorinated Hydrocarbons for measuring concentrations of the Category 3 chemicals hexachloroethane, hexachlorobutadiene, 2-c...

  20. Future Directions of Electromagnetic Methods for Hydrocarbon Applications

    NASA Astrophysics Data System (ADS)

    Strack, K. M.

    2014-01-01

    For hydrocarbon applications, seismic exploration is the workhorse of the industry. Only in the borehole, electromagnetic (EM) methods play a dominant role, as they are mostly used to determine oil reserves and to distinguish water from oil-bearing zones. Throughout the past 60 years, we had several periods with an increased interest in EM. This increased with the success of the marine EM industry and now electromagnetics in general is considered for many new applications. The classic electromagnetic methods are borehole, onshore and offshore, and airborne EM methods. Airborne is covered elsewhere (see Smith, this issue). Marine EM material is readily available from the service company Web sites, and here I will only mention some future technical directions that are visible. The marine EM success is being carried back to the onshore market, fueled by geothermal and unconventional hydrocarbon applications. Oil companies are listening to pro-EM arguments, but still are hesitant to go through the learning exercises as early adopters. In particular, the huge business drivers of shale hydrocarbons and reservoir monitoring will bring markets many times bigger than the entire marine EM market. Additional applications include support for seismic operations, sub-salt, and sub-basalt, all areas where seismic exploration is costly and inefficient. Integration with EM will allow novel seismic methods to be applied. In the borehole, anisotropy measurements, now possible, form the missing link between surface measurements and ground truth. Three-dimensional (3D) induction measurements are readily available from several logging contractors. The trend to logging-while-drilling measurements will continue with many more EM technologies, and the effort of controlling the drill bit while drilling including look-ahead-and-around the drill bit is going on. Overall, the market for electromagnetics is increasing, and a demand for EM capable professionals will continue. The emphasis will

  1. Method for removing chlorine compounds from hydrocarbon mixtures

    DOEpatents

    Janoski, E.J.; Hollstein, E.J.

    1984-09-29

    A process for removing halide ions from a hydrocarbon feedstream containing halogenated hydrocarbons wherein the contaminated feedstock is contacted with a solution of a suitable oxidizing acid containing a lanthanide oxide, the acid being present in a concentration of at least about 50 weight percent for a time sufficient to remove substantially all of the halide ion from the hydrocarbon feedstock.

  2. Method for removing chlorine compounds from hydrocarbon mixtures

    DOEpatents

    Janoski, Edward J.; Hollstein, Elmer J.

    1985-12-31

    A process for removing halide ions from a hydrocarbon feedstream containing halogenated hydrocarbons wherein the contaminated feedstock is contacted with a solution of a suitable oxidizing acid containing a lanthanide oxide, the acid being present in a concentration of at least about 50 weight percent for a time sufficient to remove substantially all of the halide ion from the hydrocarbon feedstock.

  3. Method for recovering hydrocarbons from molten metal halides

    DOEpatents

    Pell, Melvyn B.

    1979-01-01

    In a process for hydrocracking heavy carbonaceous materials by contacting such carbonaceous materials with hydrogen in the presence of a molten metal halide catalyst to produce hydrocarbons having lower molecular weights and thereafter recovering the hydrocarbons so produced from the molten metal halide, an improvement comprising injecting into the spent molten metal halide, a liquid low-boiling hydrocarbon stream is disclosed.

  4. Combination Gravimetric/Volumetric Sorption Instrument for Energy Applications

    NASA Astrophysics Data System (ADS)

    Bethea, Donald; Burress, Jacob

    The use of gaseous fuels such as hydrogen and methane (natural gas) will reduce emissions. Unfortunately, the storage of hydrogen and methane at room temperature is difficult because they are both supercritical gases, making the adoption of these fuels cumbersome. One means of overcoming the storage problem is to use physisorption-based systems which exploit the van der Waals interaction between the gas and a nanoporous material to compress the gases to near liquid densities. To measure the amount of gas in these materials, gravimetric or volumetric methods are employed. Gravimetric weighs the amount of gas and volumetric uses differences in gas pressures. Gravimetric systems typically have problems with buoyancy corrections. Volumetric systems normally have larger uncertainties that propagate through the isotherm. A modified system will be presented which allows for both gravimetric and volumetric gas sorption measurements. Additionally, the buoyancy corrections for the gravimetric measurements are significantly small and less than the uncertainties in the measurement. This apparatus can take measurements of most gases at room temperature and up to 200 bar.

  5. Novel method for cleaning a vacuum chamber from hydrocarbon contamination

    SciTech Connect

    Wanzenboeck, H. D.; Roediger, P.; Hochleitner, G.; Bertagnolli, E.; Buehler, W.

    2010-11-15

    A novel method for cleaning a high vacuum chamber is presented. This method is based on concurrent in situ high-energetic UV light activation of contaminants located in the residual gas and at the vacuum chamber surfaces as well as the in situ generation of highly reactive ozone. Ozone oxidizes the contaminants to volatile species. Investigations by energy-dispersive x-ray analysis of residual gas depositions and mass-spectroscopy measurements of the residual gas in the vacuum chamber identify the contaminant species as hydrocarbons. After a cleaning period of 8 h, a decrease in measured chamber contamination by about 90% could be achieved according to atomic force microscope analysis. Mass spectroscopy measurements using a residual gas analyzer indicate the creation of volatile, carbonaceous species during the cleaning process.

  6. Solution mining systems and methods for treating hydrocarbon containing formations

    SciTech Connect

    Vinegar, Harold J.; de Rouffignac, Eric Pierre; Schoeling, Lanny Gene

    2009-07-14

    A method for treating an oil shale formation comprising nahcolite is disclosed. The method includes providing a first fluid to a portion of the formation through at least two injection wells. A second fluid is produced from the portion through at least one injection well until at least two injection wells are interconnected such that fluid can flow between the two injection wells. The second fluid includes at least some nahcolite dissolved in the first fluid. The first fluid is injected through one of the interconnected injection wells. The second fluid is produced from at least one of the interconnected injection wells. Heat is provided from one or more heaters to the formation to heat the formation. Hydrocarbon fluids are produced from the formation.

  7. Downhole fluid injection systems, CO2 sequestration methods, and hydrocarbon material recovery methods

    DOEpatents

    Schaef, Herbert T.; McGrail, B. Peter

    2015-07-28

    Downhole fluid injection systems are provided that can include a first well extending into a geological formation, and a fluid injector assembly located within the well. The fluid injector assembly can be configured to inject a liquid CO2/H2O-emulsion into the surrounding geological formation. CO2 sequestration methods are provided that can include exposing a geological formation to a liquid CO2/H2O-emulsion to sequester at least a portion of the CO2 from the emulsion within the formation. Hydrocarbon material recovery methods are provided that can include exposing a liquid CO2/H2O-emulsion to a geological formation having the hydrocarbon material therein. The methods can include recovering at least a portion of the hydrocarbon material from the formation.

  8. Method for producing hydrocarbon and alcohol mixtures. [Patent application

    DOEpatents

    Compere, A.L.; Googin, J.M.; Griffith, W.L.

    1980-12-01

    It is an object of this invention to provide an efficient process for extracting alcohols and ketones from an aqueous solution containing the same into hydrocarbon fuel mixtures, such as gasoline, diesel fuel and fuel oil. Another object of the invention is to provide a mixture consisting of hydrocarbon, alcohols or ketones, polyoxyalkylene polymer and water which can be directly added to fuels or further purified. The above stated objects are achieved in accordance with a preferred embodiment of the invention by contacting an aqueous fermentation liquor with a hydrocarbon or hydrocarbon mixture containing carbon compounds having 5 to 18 carbon atoms, which may include gasoline, diesel fuel or fuel oil. The hydrocarbon-aqueous alcohol solution is mixed in the presence or one or more of a group of polyoxyalkylene polymers described in detail hereinafter; the fermentation alcohol being extracted into the hydrocarbon fuel-polyoxyalkylene polymer mixture.

  9. Method and apparatus for hydrocarbon recovery from tar sands

    DOEpatents

    Westhoff, James D.; Harak, Arnold E.

    1989-01-01

    A method and apparatus for utilizing tar sands having a broad range of bitumen content is disclosed. More particularly, tar sands are pyrolyzed in a cyclone retort with high temperature gases recycled from the cyclone retort to produce oil and hydrocarbon products. The spent tar sands are then burned at 2000.degree. F. in a burner to remove residual char and produce a solid waste that is easily disposable. The process and apparatus have the advantages of being able to utilize tar sands having a broad range of bitumen content and the advantage of producing product gases that are free from combustion gases and thereby have a higher heating value. Another important advantage is rapid pyrolysis of the tar sands in the cyclone so as to effectively utilize smaller sized reactor vessels for reducing capitol and operating costs.

  10. Method and apparatus for hydrocarbon recovery from tar sands

    DOEpatents

    Westhoff, J.D.; Harak, A.E.

    1988-05-04

    A method and apparatus for utilizing tar sands having a broad range of bitumen content is disclosed. More particularly, tar sands are pyrolyzed in a cyclone retort with high temperature gases recycled from the cyclone retort to produce oil and hydrocarbon products. The spent tar sands are then burned at 2000/degree/F in a burner to remove residual char and produce a solid waste that is easily disposable. The process and apparatus have the advantages of being able to utilize tar sands having a broad range of bitumen content and the advantage of producing product gases that are free from combustion gases and thereby have a higher heating value. Another important advantage is rapid pyrolysis of the tar sands in the cyclone so as to effectively utilize smaller sized reactor vessels for reducing capitol and operating costs. 1 fig., 1 tab.

  11. Systems and methods for producing hydrocarbons from tar sands formations

    DOEpatents

    Li, Ruijian; Karanikas, John Michael

    2009-07-21

    A system for treating a tar sands formation is disclosed. A plurality of heaters are located in the formation. The heaters include at least partially horizontal heating sections at least partially in a hydrocarbon layer of the formation. The heating sections are at least partially arranged in a pattern in the hydrocarbon layer. The heaters are configured to provide heat to the hydrocarbon layer. The provided heat creates a plurality of drainage paths for mobilized fluids. At least two of the drainage paths converge. A production well is located to collect and produce mobilized fluids from at least one of the converged drainage paths in the hydrocarbon layer.

  12. Apparatus and method for rapid separation and detection of hydrocarbon fractions in a fluid stream

    SciTech Connect

    Sluder, Charles S.; Storey, John M.; Lewis, Sr., Samuel A.

    2013-01-22

    An apparatus and method for rapid fractionation of hydrocarbon phases in a sample fluid stream are disclosed. Examples of the disclosed apparatus and method include an assembly of elements in fluid communication with one another including one or more valves and at least one sorbent chamber for removing certain classifications of hydrocarbons and detecting the remaining fractions using a detector. The respective ratios of hydrocarbons are determined by comparison with a non separated fluid stream.

  13. Sample preparation for thermo-gravimetric determination and thermo-gravimetric characterization of refuse derived fuel.

    PubMed

    Robinson, T; Bronson, B; Gogolek, P; Mehrani, P

    2016-02-01

    Thermo-gravimetric analysis (TGA) is a useful method for characterizing fuels. In the past it has been applied to the study of refuse derived fuel (RDF) and related materials. However, the heterogeneity of RDF makes the preparation of small representative samples very difficult and this difficulty has limited the effectiveness of TGA for characterization of RDF. A TGA method was applied to a variety of materials prepared from a commercially available RDF using a variety of procedures. Applicability of TGA method to the determination of the renewable content of RDF was considered. Cryogenic ball milling was found to be an effective means of preparing RDF samples for TGA. When combined with an effective sample preparation, TGA could be used as an alternative method for assessing the renewable content of RDF. PMID:26611398

  14. Exploration method using electron spin resonance signals from hydrocarbon crude

    SciTech Connect

    Nicksic, S.W.; Starke, G.W.

    1986-08-19

    An exploration method is described for mapping the subsurface course of crude petroleum accumulated in a producible subsurface reservoir by distinguishing crude petroleum based electron spin resonance signals from electron spin resonance signals from other constituent materials in earth formation samples. The method consists of: (a) collecting samples of subsurface earth formation materials from known positions within a formation from wells having known locations; (b) subjecting the earth formation samples to suitable conditions for the establishment of electron spin resonance of electrons present in the samples, and detecting electron spin resonance from the samples; (c) selecting those earth formation samples from which the electron spin resonance signals were detected and contacting the selected samples with a solution containing iodine; (d) subjecting the selected and contacted samples to the suitable conditions for establishment of electron spin resonance of electrons present in the samples, and detecting electron spin resonance signals from the selected samples; (e) identifying from the first selected samples those earth formation samples from which enhanced electron spin resonance signals were detected attributable to the contacting with the solution containing iodine as samples containing electrons associated with crude petroleum; (f) mapping the presence of the crude petroleum materials; (g) producing a representation of potential migration paths of hydrocarbon crudes within the formation; and (h) locating the origin of the identified samples demonstrating the enhanced electron spin resonance signals in distance, direction and depth with respect to the subsurface reservoir by using the mapped potential migration paths.

  15. Method for direct production of carbon disulfide and hydrogen from hydrocarbons and hydrogen sulfide feedstock

    SciTech Connect

    Miao, Frank Q.; Erekson, Erek James

    1998-12-01

    A method for converting hydrocarbons and hydrogen sulfide to carbon disulfide and hydrogen is provided comprising contacting the hydrocarbons and hydrogen sulfide to a bi-functional catalyst residing in a controlled atmosphere for a time and at a temperature sufficient to produce carbon disulfide and hydrogen. Also provided is a catalyst for converting carbon sulfides and hydrogen sulfides to gasoline range hydrocarbons comprising a mixture containing a zeolite catalyst and a hydrogenating catalyst.

  16. Composition and method for coke retardant during hydrocarbon processing

    SciTech Connect

    Reid, D.K.

    1988-02-09

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

  17. Method and apparatus for monitoring a hydrocarbon-selective catalytic reduction device

    DOEpatents

    Schmieg, Steven J; Viola, Michael B; Cheng, Shi-Wai S; Mulawa, Patricia A; Hilden, David L; Sloane, Thompson M; Lee, Jong H

    2014-05-06

    A method for monitoring a hydrocarbon-selective catalytic reactor device of an exhaust aftertreatment system of an internal combustion engine operating lean of stoichiometry includes injecting a reductant into an exhaust gas feedstream upstream of the hydrocarbon-selective catalytic reactor device at a predetermined mass flowrate of the reductant, and determining a space velocity associated with a predetermined forward portion of the hydrocarbon-selective catalytic reactor device. When the space velocity exceeds a predetermined threshold space velocity, a temperature differential across the predetermined forward portion of the hydrocarbon-selective catalytic reactor device is determined, and a threshold temperature as a function of the space velocity and the mass flowrate of the reductant is determined. If the temperature differential across the predetermined forward portion of the hydrocarbon-selective catalytic reactor device is below the threshold temperature, operation of the engine is controlled to regenerate the hydrocarbon-selective catalytic reactor device.

  18. Nonthermal plasma systems and methods for natural gas and heavy hydrocarbon co-conversion

    DOEpatents

    Kong, Peter C.; Nelson, Lee O.; Detering, Brent A.

    2005-05-24

    A reactor for reactive co-conversion of heavy hydrocarbons and hydrocarbon gases and includes a dielectric barrier discharge plasma cell having a pair of electrodes separated by a dielectric material and passageway therebetween. An inlet is provided for feeding heavy hydrocarbons and other reactive materials to the passageway of the discharge plasma cell, and an outlet is provided for discharging reaction products from the reactor. A packed bed catalyst may optionally be used in the reactor to increase efficiency of conversion. The reactor can be modified to allow use of a variety of light sources for providing ultraviolet light within the discharge plasma cell. Methods for upgrading heavy hydrocarbons are also disclosed.

  19. The Nonmethane Hydrocarbon Intercomparison Experiment (NOMHICE): Tasks 1 and 2

    NASA Astrophysics Data System (ADS)

    Apel, Eric C.; Calvert, Jack G.; Fehsenfeld, Fred C.

    1994-08-01

    The NOMHICE program has been designed to evaluate current methods being used to determine the ambient levels of various atmospheric nonmethane hydrocarbons, to identify existing problems in these analyses, to correct these problems, and to help ensure quality control of hydrocarbon analyses made by atmospheric scientists throughout the world. To accomplish this, a series of planned experiments (tasks) is now under way which involves all the common classes of the atmospheric hydrocarbons: alkanes, alkenes, alkynes, aromatic hydrocarbons, and the terpenes. The various tasks of the study have been scheduled in order of increasing complexity so that problems can be addressed as they arise. Preliminary results are presented for task 1 and task 2 of a multitask program. Each laboratory used its own analysis and calibration procedures. The first task of NOMHICE involved the circulation of a two-component, gravimetrically prepared, hydrocarbon mixture of known composition and unknown concentration to 36 participating scientific groups from laboratories throughout the world. This experiment was planned to check on the reliability of the standards employed by each of the participating groups. Task 2 involved the circulation, to participant laboratories, of a more complex, gravimetrically prepared, 16-component hydrocarbon mixture (unknown composition and concentration) to determine whether suitable separation, identification, and quantification can be made of the individual hydrocarbons present in the mixture. Further tasks are described which will be carried out in the future.

  20. The Nonmethane Hydrocarbon Intercomparison Experiment (NOMHICE): Tasks 1 and 2

    SciTech Connect

    Apel, E.C.; Calvert, J.G.; Fehsenfeld, F.C.

    1994-08-20

    The NOMHICE program has been designed to evaluate current methods being used to determine the ambient levels of various atmospheric nonmethane hydrocarbons, to identify existing problems in these analyses, to correct these problems, and to help ensure quality control of hydrocarbon analyses made by atmospheric scientists throughout the world. To accomplish this, a series of planned experiments (tasks) is now under way which involves all the common classes of the atmospheric hydrocarbons: alkanes, alkenes, alkynes, aromatic hydrocarbons, and the terpenes. The various tasks of the study have been scheduled in order of increasing complexity so that problems can be addressed as they arise. Preliminary results are presented for task 1 and task 2 of a multitask program. Each laboratory used its own analysis and calibration procedures. The first task of NOMHICE involved the circulation of a two-component, gravimetrically prepared, hydrocarbon mixture of known composition and unknown concentration to 36 participating scientific groups from laboratories throughout the world. This experiment was planned to check on the reliability of the standards employed by each of the participating groups. Task 2 involved the circulation, to participant laboratories, of a more complex, gravimetrically prepared, 16-component hydrocarbon mixture (unknown composition and concentration) to determine whether suitable separation, identification, and quantification can be made of the individual hydrocarbons present in the mixture. Further tasks are described which will be carried out in the future. 16 refs., 12 figs., 3 tabs.

  1. Compounds and methods for the production of long chain hydrocarbons from biological sources

    DOEpatents

    Gordon, John Cameron; Silks, Louis A; Sutton, Andrew D; Wu, Ruilian; Schlaf, Marcel; Waldie, Fraser; West, Ryan; Collias, Dimitris Ioannis

    2016-08-23

    The present invention is directed to the preparation of oxygenated, unsaturated hydrocarbon compounds, such as derivatives of furfural or hydroxymethyl furfural produced by aldol condensation with a ketone or a ketoester, as well as methods of deoxidatively reducing those compounds with hydrogen under acidic conditions to provide saturated hydrocarbons useful as fuels.

  2. Method for producing hydrocarbon fuels from heavy polynuclear hydrocarbons by use of molten metal halide catalyst

    DOEpatents

    Gorin, Everett

    1979-01-01

    In a process for hydrocracking heavy polynuclear carbonaceous feedstocks to produce lighter hydrocarbon fuels by contacting the heavy feedstocks with hydrogen in the presence of a molten metal halide catalyst, thereafter separating at least a substantial portion of the carbonaceous material associated with the reaction mixture from the spent molten metal halide and thereafter regenerating the metal halide catalyst, an improvement comprising contacting the spent molten metal halide catalyst after removal of a major portion of the carbonaceous material therefrom with an additional quantity of hydrogen is disclosed.

  3. Method and apparatus for production of subsea hydrocarbon formations

    DOEpatents

    Blandford, J.W.

    1995-01-17

    A system for controlling, separating, processing and exporting well fluids produced from subsea hydrocarbon formations is disclosed. The subsea well tender system includes a surface buoy supporting one or more decks above the water surface for accommodating equipment to process oil, gas and water recovered from the subsea hydrocarbon formation. The surface buoy includes a surface-piercing central flotation column connected to one or more external flotation tanks located below the water surface. The surface buoy is secured to the sea bed by one or more tendons which are anchored to a foundation with piles imbedded in the sea bed. The system accommodates multiple versions on the surface buoy configuration. 20 figures.

  4. Method and apparatus for production of subsea hydrocarbon formations

    DOEpatents

    Blandford, Joseph W.

    1995-01-01

    A system for controlling, separating, processing and exporting well fluids produced from subsea hydrocarbon formations is disclosed. The subsea well tender system includes a surface buoy supporting one or more decks above the water surface for accommodating equipment to process oil, gas and water recovered from the subsea hydrocarbon formation. The surface buoy includes a surface-piercing central flotation column connected to one or more external floatation tanks located below the water surface. The surface buoy is secured to the seabed by one or more tendons which are anchored to a foundation with piles imbedded in the seabed. The system accommodates multiple versions on the surface buoy configuration.

  5. Method for silicon carbide production by reacting silica with hydrocarbon gas

    DOEpatents

    Glatzmaier, G.C.

    1994-06-28

    A method is described for producing silicon carbide particles using a silicon source material and a hydrocarbon. The method is efficient and is characterized by high yield. Finely divided silicon source material is contacted with hydrocarbon at a temperature of 400 C to 1000 C where the hydrocarbon pyrolyzes and coats the particles with carbon. The particles are then heated to 1100 C to 1600 C to cause a reaction between the ingredients to form silicon carbide of very small particle size. No grinding of silicon carbide is required to obtain small particles. The method may be carried out as a batch process or as a continuous process. 5 figures.

  6. Method for silicon carbide production by reacting silica with hydrocarbon gas

    DOEpatents

    Glatzmaier, Gregory C.

    1994-01-01

    A method is described for producing silicon carbide particles using a silicon source material and a hydrocarbon. The method is efficient and is characterized by high yield. Finely divided silicon source material is contacted with hydrocarbon at a temperature of 400.degree. C. to 1000.degree. C. where the hydrocarbon pyrolyzes and coats the particles with carbon. The particles are then heated to 1100.degree. C. to 1600.degree. C. to cause a reaction between the ingredients to form silicon carbide of very small particle size. No grinding of silicon carbide is required to obtain small particles. The method may be carried out as a batch process or as a continuous process.

  7. Apparatus for hydrocarbon extraction

    DOEpatents

    Bohnert, George W.; Verhulst, Galen G.

    2013-03-19

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

  8. Method for cracking hydrocarbon compositions using a submerged reactive plasma system

    DOEpatents

    Kong, P.C.

    1997-05-06

    A method is described for cracking a liquid hydrocarbon composition (e.g. crude oil) to produce a cracked hydrocarbon product. A liquid hydrocarbon composition is initially provided. An electrical arc is generated directly within the hydrocarbon composition so that the arc is entirely submerged in the composition. Arc generation is preferably accomplished using a primary and secondary electrode each having a first end submerged in the composition. The first ends of the electrodes are separated from each other to form a gap there between. An electrical potential is then applied to the electrodes to generate the arc within the gap. A reactive gas is thereafter delivered to the arc which forms a bubble around the arc. Gas delivery may be accomplished by providing a passageway through each electrode and delivering the gas through the passageways. The arc and gas cooperate to produce a plasma which efficiently cracks the hydrocarbon composition. 6 figs.

  9. Method for cracking hydrocarbon compositions using a submerged reactive plasma system

    DOEpatents

    Kong, Peter C.

    1997-01-01

    A method for cracking a liquid hydrocarbon composition (e.g. crude oil) to produce a cracked hydrocarbon product. A liquid hydrocarbon composition is initially provided. An electrical arc is generated directly within the hydrocarbon composition so that the arc is entirely submerged in the composition. Arc generation is preferably accomplished using a primary and secondary electrode each having a first end submerged in the composition. The first ends of the electrodes are separated from each other to form a gap therebetween. An electrical potential is then applied to the electrodes to generate the arc within the gap. A reactive gas is thereafter delivered to the arc which forms a bubble around the arc. Gas delivery may be accomplished by providing a passageway through each electrode and delivering the gas through the passageways. The arc and gas cooperate to produce a plasma which efficiently cracks the hydrocarbon composition.

  10. Flow Injection as a Teaching Tool for Gravimetric Analysis

    NASA Astrophysics Data System (ADS)

    Sartini, Raquel P.; Zagatto, Elias A. G.; Oliveira, Cláudio C.

    2000-06-01

    A flow-injection system to carry out gravimetric analysis is presented. Students are faced with an instrumental approach for gravimetric procedures. Crucibles, muffle furnaces, and desiccators are not required. A flowing suspension is established by simultaneously injecting an aqueous sample and a precipitating reagent into two merging carrier streams. The precipitate is accumulated on a minifilter hanging under the plate of an analytical balance and is weighed inside the main stream. Since Archimedes' principle holds, a drying step is not needed. After measurement, the precipitate is dissolved and disposed of. As an application, the determination of phosphate based on precipitation with ammonium and magnesium ions in slightly alkaline medium is chosen. The proposed system is very stable and well suited for demonstration. When applied to analysis of fertilizer extracts with 0.10-1.00% w/v P, it yields precise results (RSD < 0.042) in agreement with an official spectrophotometric method.

  11. Delineation of Hydrocarbon Contamination of Soils and Sediments With Environmental Magnetic Methods: Laboratory and Field Studies

    NASA Astrophysics Data System (ADS)

    Rijal, M. L.; Appel, E.; Porsch, K.; Kappler, A.; Blaha, U.; Petrovsky, E.

    2008-12-01

    Hydrocarbon contamination of soils and sediments is a worldwide environmental problem. The present research focuses on the study of magnetic properties of hydrocarbon contaminated soils and sediments using environmental magnetic methods both on field sites as well as in laboratory batch experiments. The main objectives of this research are i) to determine a possible application of magnetic proxies for the delineation of organic contamination in soils and sediments and ii) to examine the role of bacteria in changing soil magnetic properties after hydrocarbon contamination. A former oil field and a former military site which are heavily contaminated with hydrocarbons were studied. Additionally, three different types of natural clean soils were investigated in laboratory experiments by simulating hydrocarbon contamination in sterile and microbial active setups. Magnetic properties, soil properties, iron bioavailability, iron redox state and hydrocarbon content of samples were measured. Additionally, magnetic susceptibility (MS) was monitored weekly in laboratory batch set-ups during several months. Results from the field sites showed that there is an increase of MS and a good correlation between MS and hydrocarbon content. A weekly monitored MS result from the laboratory study clearly indicated~~10% change (increase as well as decrease) of initial MS of respective soils only in microbial active set-ups with saturation after a few weeks of experimental period. This depicts that there is a change of MS caused by microbial iron mineral transformation in presence of hydrocarbon contamination in soils. The results from the field study demonstrate that magnetic proxies can be used to localize hydrocarbon contamination. However, more field sites with hydrocarbon contaminated soils and sediments need to be investigated by using environmental magnetic methods for better understanding the factors driving such changes in magnetic properties.

  12. Gravimetric maps of the Central African Republic

    NASA Technical Reports Server (NTRS)

    Albouy, J.; Godivier, R. (Principal Investigator)

    1982-01-01

    Gravimetric maps of the Central African Republic are described including a map of Bouguer anomalies at 1/1,000,000 in two sections (eastern sheet, western sheet) and a map, in color, of Bouguer anomalies at 1/2,000,000. Instrumentation, data acquisition, calibration, and data correction procedures are discussed.

  13. COMPUTATIONAL METHODS FOR STUDYING THE INTERACTION BETWEEN POLYCYCLIC AROMATIC HYDROCARBONS AND BIOLOGICAL MACROMOLECULES

    EPA Science Inventory

    Computational Methods for Studying the Interaction between Polycyclic Aromatic Hydrocarbons and Biological Macromolecules .

    The mechanisms for the processes that result in significant biological activity of PAHs depend on the interaction of these molecules or their metabol...

  14. Method for direct conversion of gaseous hydrocarbons to liquids

    DOEpatents

    Kong, Peter C.; Lessing, Paul A.

    2006-03-07

    A chemical reactor for direct conversion of hydrocarbons includes a dielectric barrier discharge plasma cell and a solid oxide electrochemical cell in fluid communication therewith. The discharge plasma cell comprises a pair of electrodes separated by a dielectric material and passageway therebetween. The electrochemical cell comprises a mixed-conducting solid oxide electrolyte membrane tube positioned between a porous cathode and a porous anode, and a gas inlet tube for feeding oxygen containing gas to the porous cathode. An inlet is provided for feeding hydrocarbons to the passageway of the discharge plasma cell, and an outlet is provided for discharging reaction products from the reactor. A packed bed catalyst may optionally be used in the reactor to increase efficiency of conversion. The reactor can be modified to allow use of a light source for directing ultraviolet light into the discharge plasma cell and the electrochemical cell.

  15. Method for removing hydrocarbon contaminants from solid materials

    DOEpatents

    Bala, G.A.; Thomas, C.P.

    1995-10-03

    A system is described for removing hydrocarbons from solid materials. Contaminated solids are combined with a solvent (preferably terpene based) to produce a mixture. The mixture is washed with water to generate a purified solid product (which is removed from the system) and a drainage product. The drainage product is separated into a first fraction (consisting mostly of contaminated solvent) and a second fraction (containing solids and water). The first fraction is separated into a third fraction (consisting mostly of contaminated solvent) and a fourth fraction (containing residual solids and water). The fourth fraction is combined with the second fraction to produce a sludge which is separated into a fifth fraction (containing water which is ultimately reused) and a sixth fraction (containing solids). The third fraction is then separated into a seventh fraction (consisting of recovered solvent which is ultimately reused) and an eighth fraction (containing hydrocarbon waste). 4 figs.

  16. Method for removing hydrocarbon contaminants from solid materials

    DOEpatents

    Bala, Gregory A.; Thomas, Charles P.

    1995-01-01

    A system for removing hydrocarbons from solid materials. Contaminated solids are combined with a solvent (preferably terpene based) to produce a mixture. The mixture is washed with water to generate a purified solid product (which is removed from the system) and a drainage product. The drainage product is separated into a first fraction (consisting mostly of contaminated solvent) and a second fraction (containing solids and water). The first fraction is separated into a third fraction (consisting mostly of contaminated solvent) and a fourth fraction (containing residual solids and water). The fourth fraction is combined with the second fraction to produce a sludge which is separated into a fifth fraction (containing water which is ultimately reused) and a sixth fraction (containing solids). The third fraction is then separated into a seventh fraction (consisting of recovered solvent which is ultimately reused) and an eighth fraction (containing hydrocarbon waste).

  17. Method and apparatus for production of subsea hydrocarbon formations

    DOEpatents

    Blandford, Joseph W.

    1992-01-01

    A well tender system for controlling, separating, storing and offloading well fluids produced from subsea hydrocarbon formations. The system comprises a vertically aligned series of tethered cylindrical tanks which are torsionally stabilized by flexible catenary production riser and expert riser bundles, and serviced by separate catenary pipe bundles. Piles are secured to the seabed, each pile assembly being pivotally connected to a lower rigid tendon, which is in turn connected to tendons arranged about the periphery of the interconnected cylindrical tanks.

  18. Method and apparatus for production of subsea hydrocarbon formations

    DOEpatents

    Blandford, Joseph W.

    1994-01-01

    A well tender system for controlling, separating, storing and offloading well fluids produced from subsea hydrocarbon formations. The system comprises a vertically aligned series of tethered cylindrical tanks which are torsionally stabilized by flexible catenary production riser and export riser bundles, and serviced by separate catenary pipe bundles. Piles are secured to the seabed, each pile assembly being pivotally connected to a lower rigid tendon, which is in turn connected to tendons arranged about the periphery of the interconnected cylindrical tanks.

  19. Methods of producing alkylated hydrocarbons from an in situ heat treatment process liquid

    DOEpatents

    Roes, Augustinus Wilhelmus Maria; Mo, Weijian; Muylle, Michel Serge Marie; Mandema, Remco Hugo; Nair, Vijay

    2009-09-01

    A method for producing alkylated hydrocarbons is disclosed. Formation fluid is produced from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes olefins. The liquid stream is fractionated to produce at least a second gas stream including hydrocarbons having a carbon number of at least 3. The first gas stream and the second gas stream are introduced into an alkylation unit to produce alkylated hydrocarbons. At least a portion of the olefins in the first gas stream enhance alkylation.

  20. New method for determining heats of combustion of gaseous hydrocarbons

    NASA Technical Reports Server (NTRS)

    Singh, J. J.; Sprinkle, D. R.; Puster, R. L.

    1985-01-01

    As a spin off of a system developed for monitoring and controlling the oxygen concentration in the Langley 8-foot High Temperature Tunnel, a highly accurate on-line technique was developed for determining heats of combustion of natural gas samples. It is based on measuring the ratio m/n, where m is the (volumetric) flowrate of oxygen required to enrich the carrier air in which the test gas flowing at the rate n is burned, such that the mole fraction of oxygen in the combustion product gases equals that in the carrier air. The m/n ratio is directly related to the heats of combustion of the saturated hydrocarbons present in the natural gas. A measurement of the m/n ratio for the test gas can provide a direct means of determination of its heat of combustion by using the calibration graph relating the m/n values for pure saturated hydrocarbons with their heats of combustion. The accuracy of the technique is determine solely by the accuracy with which the flowrates m and n can be measured and is of the order of 2 percent in the present study. The theoretical principles and experimental results are discussed.

  1. Advances on Empirical Mode Decomposition-based Time-Frequency Analysis Methods in Hydrocarbon Detection

    NASA Astrophysics Data System (ADS)

    Chen, H. X.; Xue, Y. J.; Cao, J.

    2015-12-01

    Empirical mode decomposition (EMD), which is a data-driven adaptive decomposition method and is not limited by time-frequency uncertainty spreading, is proved to be more suitable for seismic signals which are nonlinear and non-stationary. Compared with other Fourier-based and wavelet-based time-frequency methods, EMD-based time-frequency methods have higher temporal and spatial resolution and yield hydrocarbon interpretations with more statistical significance. Empirical mode decomposition algorithm has now evolved from EMD to Ensemble EMD (EEMD) to Complete Ensemble EMD (CEEMD). Even though EMD-based time-frequency methods offer many promising features for analyzing and processing geophysical data, there are some limitations or defects in EMD-based time-frequency methods. This presentation will present a comparative study on hydrocarbon detection using seven EMD-based time-frequency analysis methods, which include: (1) first, EMD combined with Hilbert transform (HT) as a time-frequency analysis method is used for hydrocarbon detection; and (2) second, Normalized Hilbert transform (NHT) and HU Methods respectively combined with HT as improved time-frequency analysis methods are applied for hydrocarbon detection; and (3) three, EMD combined with Teager-Kaiser energy (EMD/TK) is investigated for hydrocarbon detection; and (4) four, EMD combined with wavelet transform (EMDWave) as a seismic attenuation estimation method is comparatively studied; and (5) EEMD- and CEEMD- based time-frequency analysis methods used as highlight volumes technology are studied. The differences between these methods in hydrocarbon detection will be discussed. The question of getting a meaningful instantaneous frequency by HT and mode-mixing issues in EMD will be analysed. The work was supported by NSFC under grant Nos. 41430323, 41404102 and 41274128.

  2. Method and apparatus for recovering fractions from hydrocarbon materials, facilitating the removal and cleansing of hydrocarbon fluids, insulating storage vessels, and cleansing storage vessels and pipelines

    SciTech Connect

    Klaila, W.J.

    1991-10-08

    This patent describes a method for sequentially recovering fractions from hydrocarbon material. It comprises: generating electromagnetic energy in the frequency range of from about 300 megahertz to abut 300 gigahertz; broadcasting the generated electromagnetic energy to a deflector, the deflector deflecting the electromagnetic energy towards a plurality of locations in the hydrocarbon material for exposure thereto; exposing the hydrocarbon material at the plurality of locations to the electromagnetic energy; sensing the temperature of the hydrocarbon material by means of sensors that are positioned at the plurality of locations; moving the deflector and deflecting the electromagnetic energy towards the hydrocarbon material as a function of the temperature sensed at the plurality of locations to control the temperature of the hydrocarbon material at the plurality of locations; continuously generating the electromagnetic energy while selectively changing the locations of the deflector relative to the hydrocarbon material in response to the temperature sensed by the sensors to concentrate the electromagnetic energy in different locations of the hydrocarbon material as a function of the temperature sensed at the plurality of locations.

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

    SciTech Connect

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

    2013-02-05

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

  4. Use of the Complex Conductivity Method to Monitor Hydrocarbon Degradation in Brackish Environments

    NASA Astrophysics Data System (ADS)

    Ntarlagiannis, D.; Beaver, C. L.; Kimak, C.; Slater, L. D.; Atekwana, E. A.; Rossbach, S.

    2015-12-01

    Hydrocarbon contamination of the subsurface is a global environmental problem. The size, location and recurrence rate of contamination very often inhibits active remediation strategies. When there is no direct threat to humans, and direct/invasive remediation methods are prohibited, monitored natural attenuation is often the remediation method of choice. Consequently, long-term monitoring of hydrocarbon degradation is needed to validate remediation. Geophysical methods, frequently utilized to characterize subsurface contamination, have the potential to be adopted for long term monitoring of contaminant degradation. Over the last decade, the complex conductivity method has shown promise as a method for monitoring hydrocarbon degradation processes in freshwater environments. We investigated the sensitivity of complex conductivity to natural attenuation of oil in a brackish setting, being more representative of the conditions where most oil spills occur such as in coastal environments. We performed a series of laboratory hydrocarbon biodegradation experiments whilst continuously monitoring complex conductivity. Sediments from a beach impacted by the Deepwater Horizon (DWH) spill were used to provide the hydrocarbon degraders, while fluids with three different salinities, ranging from fresh water to brackish water, were used as the supporting media. All experimental columns, including two abiotic controls, were run in duplicate. Early results show a dependence of the complex conductivity parameters (both electrolytic and interfacial) on biodegradation processes. Despite the small signals relative to freshwater conditions, the imaginary part of the complex conductivity appears to be sensitive to biodegradation processes. The columns with highest salinity fluids - similar to the salinites for the site where the sediments were collected - showed distinctive complex conductivity responses similar to microbial growth curves. Geochemical monitoring confirmed elevated rates

  5. Estimation of the gravimetric pole tide by stacking long time-series of GGP superconducting gravimeters

    NASA Astrophysics Data System (ADS)

    Ziegler, Yann; Hinderer, Jacques; Rogister, Yves; Rosat, Séverine

    2016-04-01

    We compute the gravimetric factor at the Chandler wobble (CW) frequency using time-series from superconducting gravimeters (SG) longer than a decade. We first individually process the polar motion and data at each individual gravity station to estimate the gravimetric factor amplitude and phase, then we make a global analysis by applying a stacking method to different subsets of up to seven SG stations. The stacking is an efficient way of getting rid of local effects and improving the signal-to-noise ratio of the combined data sets. Using the stacking method, we find a gravimetric factor amplitude and phase of 1.118 ± 0.016 and -0.45 ± 0.66 deg, respectively, which is smaller in amplitude than expected. The sources of error are then carefully considered. For both local and global analyses, the uncertainties on our results are reliably constrained by computing the standard deviation of the estimates of the gravimetric factor amplitude and phase for increasing length of the time-series. Constraints on the CW anelastic dissipation can be set since any departure of the gravimetric factor from its elastic value may provide some insights into the dissipative processes that occur at the CW period. In particular, assuming given rheological models for the Earth's mantle enables us to make the link between the gravimetric factor phase and the CW quality factor.

  6. Methods of reforming hydrocarbon fuels using hexaaluminate catalysts

    SciTech Connect

    Gardner, Todd H.; Berry, David A.; Shekhawat, Dushyant

    2012-03-27

    A metal substituted hexaaluminate catalyst for reforming hydrocarbon fuels to synthesis gas of the general formula AB.sub.yAl.sub.12-yO.sub.19-.delta., A being selected from alkali metals, alkaline earth metals and lanthanide metals or mixtures thereof. A dopant or surface modifier selected from a transitions metal, a spinel of an oxygen-ion conductor is incorporated. The dopant may be Ca, Cs, K, La, Sr, Ba, Li, Mg, Ce, Co, Fe, Ir, Rh, Ni, Ru, Cu, Pe, Os, Pd, Cr, Mn, W, Re, Sn, Gd, V, Ti, Ag, Au, and mixtures thereof. The oxygen-ion conductor may be a perovskite selected from M'RhO.sub.3, M'PtO.sub.3, M'PdO.sub.3, M'IrO.sub.3, M'RuO.sub.3 wherein M'=Mg, Sr, Ba, La, Ca; a spinel selected from MRh.sub.2O.sub.4, MPt.sub.2O.sub.4, MPd.sub.2O.sub.4, MIr.sub.2O.sub.4, MRu.sub.2O.sub.4 wherein M=Mg, Sr, Ba, La, Ca and mixtures thereof; a florite is selected from M''O.sub.2.

  7. Direct injection GC method for measuring light hydrocarbon emissions from cooling-tower water.

    PubMed

    Lee, Max M; Logan, Tim D; Sun, Kefu; Hurley, N Spencer; Swatloski, Robert A; Gluck, Steve J

    2003-12-15

    A Direct Injection GC method for quantifying low levels of light hydrocarbons (C6 and below) in cooling water has been developed. It is intended to overcome the limitations of the currently available technology. The principle of this method is to use a stripper column in a GC to strip waterfrom the hydrocarbons prior to entering the separation column. No sample preparation is required since the water sample is introduced directly into the GC. Method validation indicates that the Direct Injection GC method offers approximately 15 min analysis time with excellent precision and recovery. The calibration studies with ethylene and propylene show that both liquid and gas standards are suitable for routine calibration and calibration verification. The sampling method using zero headspace traditional VOA (Volatile Organic Analysis) vials and a sample chiller has also been validated. It is apparent that the sampling method is sufficient to minimize the potential for losses of light hydrocarbons, and samples can be held at 4 degrees C for up to 7 days with more than 93% recovery. The Direct Injection GC method also offers <1 ppb (w/v) level method detection limits for ethylene, propylene, and benzene. It is superior to the existing El Paso stripper method. In addition to lower detection limits for ethylene and propylene, the Direct Injection GC method quantifies individual light hydrocarbons in cooling water, provides better recoveries, and requires less maintenance and setup costs. Since the instrumentation and supplies are readily available, this technique could easily be established as a standard or alternative method for routine emission monitoring and leak detection of light hydrocarbons in cooling-tower water. PMID:14717185

  8. Rapid method for determination of content of unsaturated hydrocarbons in naphtha cuts

    SciTech Connect

    Mozhaiko, V.N.; Seleznev, V.D.

    1988-03-01

    The method to determine total content of unsaturated hydrocarbons in naphtha cuts from reforming, cracking, and pyrolysis consisted of exhaustive catalytic hydrogenation of the unsaturated hydrocarbons, with detection of the hydrogen consumed in the hydrogenation reaction. The analyses were performed in a KhL-4 chromatography; the gas flow plan is shown. Preliminary experiments with saturated hydrocarbons (hexane, octane, decane) were performed. Naphthene experiments (methylcyclopentane, cyclohexane) showed no peak to indicate an increase in hydrogen concentration. No hydrogenation was observed in experiments with benzene and toluene. A comparison was made from analyses using the GOST 2070-82 and the rapid method as applied to IBP-180/sup 0/C cuts from reformer naphthas produced under varying conditions of severity.

  9. Method of treating emissions of a hybrid vehicle with a hydrocarbon absorber and a catalyst bypass system

    DOEpatents

    Roos, Bryan Nathaniel; Gonze, Eugene V; Santoso, Halim G; Spohn, Brian L

    2014-01-14

    A method of treating emissions from an internal combustion engine of a hybrid vehicle includes directing a flow of air created by the internal combustion engine when the internal combustion engine is spinning but not being fueled through a hydrocarbon absorber to collect hydrocarbons within the flow of air. When the hydrocarbon absorber is full and unable to collect additional hydrocarbons, the flow of air is directed through an electrically heated catalyst to treat the flow of air and remove the hydrocarbons. When the hydrocarbon absorber is not full and able to collect additional hydrocarbons, the flow of air is directed through a bypass path that bypasses the electrically heated catalyst to conserve the thermal energy stored within the electrically heated catalyst.

  10. Groundwater storage change detection using micro-gravimetric technology

    NASA Astrophysics Data System (ADS)

    El-Diasty, Mohammed

    2016-06-01

    In this paper, new perspectives and developments in applying a ground-based micro-gravimetric method to detect groundwater storage change in Waterloo Moraine are investigated. Four epochs of gravity survey were conducted using absolute gravimeter (FG5), two relative gravity meters (CG5) and two geodetic global positioning systems (GPS) in the Waterloo Moraine in May and August of 2010 and 2011, respectively. Data were processed using the parametric least-squares method and integrated with geological and hydrological studies. The gravity differences between May and August for 2010 and 2011 epochs were inverted to provide the estimated total water storage changes. Changes in soil water content obtained from land surface models of Ecological Assimilation of Land and Climate Observations (EALCO) and the Global Land Data Assimilation System (GLDAS) program were employed to estimate the groundwater storage change. The ratios between the estimated groundwater storage changes and measured water table changes (specific yields) were determined at a local monitoring well located in the survey area. The results showed that the estimates of specific yields between May and August of 2010 and 2011 were consistent at a significant confidence level and are also within the range of the specific yield from geological and hydrological studies. Therefore, the micro-gravimetric (absolute and relative gravity meters) technology has demonstrated the great potential in detecting groundwater storage change and specific yield for local scale aquifers such as Waterloo Moraine.

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

    SciTech Connect

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

    2013-07-23

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

  12. Source apportionment of urban particulate aliphatic and polynuclear aromatic hydrocarbons (PAHs) using multivariate methods.

    PubMed

    Kavouras, I G; Koutrakis, P; Tsapakis, M; Lagoudaki, E; Stephanou, E G; Von Baer, D; Oyola, P

    2001-06-01

    Samples of organic aerosol were collected in Santiago de Chile. An activated-charcoal diffusion denuder was used to strip out organic vapors prior to particle collection. Both polynuclear aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons were determined using gas chromatography/mass spectrometry (GC/MS). Organic particle sources were resolved using both concentration diagnostic ratios and multivariate methods such as hierarchical cluster analysis (HCA) and factor analysis (FA). Four factors were identified based on the loadings of PAHs and n-alkanes and were attributed to the following sources: (1) high-temperature combustion of fuels; (2) fugitive emissions from oil residues; (3) biogenic sources; and (4) unburned fuels. Multilinear regression (MLR) analysis was used to determine emission profiles and contributions of the sources. The reconstructed concentrations of particle phase aliphatic and polynuclear aromatic hydrocarbons were in good agreement (R2 > 0.70) with those measured in Santiago de Chile. PMID:11414034

  13. Methods of using structures including catalytic materials disposed within porous zeolite materials to synthesize hydrocarbons

    DOEpatents

    Rollins, Harry W.; Petkovic, Lucia M.; Ginosar, Daniel M.

    2011-02-01

    Catalytic structures include a catalytic material disposed within a zeolite material. The catalytic material may be capable of catalyzing a formation of methanol from carbon monoxide and/or carbon dioxide, and the zeolite material may be capable of catalyzing a formation of hydrocarbon molecules from methanol. The catalytic material may include copper and zinc oxide. The zeolite material may include a first plurality of pores substantially defined by a crystal structure of the zeolite material and a second plurality of pores dispersed throughout the zeolite material. Systems for synthesizing hydrocarbon molecules also include catalytic structures. Methods for synthesizing hydrocarbon molecules include contacting hydrogen and at least one of carbon monoxide and carbon dioxide with such catalytic structures. Catalytic structures are fabricated by forming a zeolite material at least partially around a template structure, removing the template structure, and introducing a catalytic material into the zeolite material.

  14. COMPARISON OF QUANTUM MECHANICAL METHODS TO COMPUTE THE BIOLOGICALLY RELEVANT REACTIVITIES OF CYCLOPENTA POLYCYCLIC AROMATIC HYDROCARBONS

    EPA Science Inventory

    In computational studies to understand the interaction of polycyclic aromatic hydrocarbons (PAHS) with biomolecular systems, the semi-empirical method AM1 has been used to determine the geometry of the PAH, its metabolites and relevant intermediates. umber of studies have shown t...

  15. An interatomic potential for saturated hydrocarbons based on the modified embedded-atom method.

    PubMed

    Nouranian, S; Tschopp, M A; Gwaltney, S R; Baskes, M I; Horstemeyer, M F

    2014-04-01

    In this work, we developed an interatomic potential for saturated hydrocarbons using the modified embedded-atom method (MEAM), a reactive semi-empirical many-body potential based on density functional theory and pair potentials. We parameterized the potential by fitting to a large experimental and first-principles (FP) database consisting of (1) bond distances, bond angles, and atomization energies at 0 K of a homologous series of alkanes and their select isomers from methane to n-octane, (2) the potential energy curves of H2, CH, and C2 diatomics, (3) the potential energy curves of hydrogen, methane, ethane, and propane dimers, i.e., (H2)2, (CH4)2, (C2H6)2, and (C3H8)2, respectively, and (4) pressure-volume-temperature (PVT) data of a dense high-pressure methane system with the density of 0.5534 g cc(-1). We compared the atomization energies and geometries of a range of linear alkanes, cycloalkanes, and free radicals calculated from the MEAM potential to those calculated by other commonly used reactive potentials for hydrocarbons, i.e., second-generation reactive empirical bond order (REBO) and reactive force field (ReaxFF). MEAM reproduced the experimental and/or FP data with accuracy comparable to or better than REBO or ReaxFF. The experimental PVT data for a relatively large series of methane, ethane, propane, and butane systems with different densities were predicted reasonably well by the MEAM potential. Although the MEAM formalism has been applied to atomic systems with predominantly metallic bonding in the past, the current work demonstrates the promising extension of the MEAM potential to covalently bonded molecular systems, specifically saturated hydrocarbons and saturated hydrocarbon-based polymers. The MEAM potential has already been parameterized for a large number of metallic unary, binary, ternary, carbide, nitride, and hydride systems, and extending it to saturated hydrocarbons provides a reliable and transferable potential for atomistic

  16. METHOD DEVELOPMENT FOR DETERMINATION OF POLYCHLORINATED HYDROCARBONS IN MUNICIPAL SLUDGE

    EPA Science Inventory

    The method provides a procedure for analysis of pesticides and PCB's in municipal sludge. The method includes extraction by a centrifuge technique of the chlorinated compounds from the sludge matrix; clean-up of the extract to remove interferences by sulfur precipitation as mercu...

  17. Photocatalytic silver enhancement reaction for gravimetric immunosensors

    NASA Astrophysics Data System (ADS)

    Seo, Hyejung; Joo, Jinmyoung; Ko, Wooree; Jung, Namchul; Jeon, Sangmin

    2010-12-01

    A novel microgravimetric immunosensor has been developed using TiO2 nanoparticle-modified immunoassay and silver enhancement reaction. An antibody-conjugated TiO2 nanoparticle is bound to the AFP antigen immobilized on a quartz resonator. When the nanoparticles are exposed to UV light in a silver nitrate solution, the photocatalytic reduction of silver ions results in the formation of metallic silver onto the nanoparticles and induces a decrease in the resonance frequency. The frequency change by this photocatalytic reduction reaction is three orders of magnitude larger than the change by antigen binding alone. The efficiency of the photocatalytic reaction has been found to increase with the fraction of anatase crystallites in the nanoparticles and the concentration of the AgNO3 solution. The results highlight the potential of the photocatalytic nanoparticles for the detection of low concentrations of target molecules using gravimetric sensors.

  18. Gravimetric examination of Hagia Sophia's subsurface structure

    NASA Astrophysics Data System (ADS)

    Friedrich, Jürgen; Gerstenecker, Carl; Gürkan, Onur

    1996-10-01

    The subsurface structure of Hagia Sophia, one of the oldest sacred monuments in the world built between 532 537 under the reign of Justinian in today's Istanbul, has been investigated by using two relative LaCoste-Romberg gravimeters in order to detect hidden cavities which have also served as earthquake dampers in similar constructions. On the building's ground floor a grid of 100 points with a grid size of about 4.m was measured. The mean gravimetric point error was ± 3.10-8 ms-2. The result of the examination is that cavities were not detected in the inner central part of Hagia Sophia with a larger diameter than 8.m down to a depth of about 20.m, and Hagia Sophia's foundation was found to be a slope of natural rock with a downward inclination to the East that has a small crest symmetrical to the building's East-West axis.

  19. DNA-based stable isotope probing coupled with cultivation methods implicates Methylophaga in hydrocarbon degradation

    PubMed Central

    Mishamandani, Sara; Gutierrez, Tony; Aitken, Michael D.

    2014-01-01

    Marine hydrocarbon-degrading bacteria perform a fundamental role in the oxidation and ultimate removal of crude oil and its petrochemical derivatives in coastal and open ocean environments. Those with an almost exclusive ability to utilize hydrocarbons as a sole carbon and energy source have been found confined to just a few genera. Here we used stable isotope probing (SIP), a valuable tool to link the phylogeny and function of targeted microbial groups, to investigate hydrocarbon-degrading bacteria in coastal North Carolina sea water (Beaufort Inlet, USA) with uniformly labeled [13C]n-hexadecane. The dominant sequences in clone libraries constructed from 13C-enriched bacterial DNA (from n-hexadecane enrichments) were identified to belong to the genus Alcanivorax, with ≤98% sequence identity to the closest type strain—thus representing a putative novel phylogenetic taxon within this genus. Unexpectedly, we also identified 13C-enriched sequences in heavy DNA fractions that were affiliated to the genus Methylophaga. This is a contentious group since, though some of its members have been proposed to degrade hydrocarbons, substantive evidence has not previously confirmed this. We used quantitative PCR primers targeting the 16S rRNA gene of the SIP-identified Alcanivorax and Methylophaga to determine their abundance in incubations amended with unlabeled n-hexadecane. Both showed substantial increases in gene copy number during the experiments. Subsequently, we isolated a strain representing the SIP-identified Methylophaga sequences (99.9% 16S rRNA gene sequence identity) and used it to show, for the first time, direct evidence of hydrocarbon degradation by a cultured Methylophaga sp. This study demonstrates the value of coupling SIP with cultivation methods to identify and expand on the known diversity of hydrocarbon-degrading bacteria in the marine environment. PMID:24578702

  20. Methods for treating hydrocarbon recovery operations and industrial waters

    SciTech Connect

    Thompson, N.E.S.; Asperger, R.G.

    1989-05-02

    This patent describes a method for consisting adding to the emulsion an effective demulsifying amount of a composition comprising a compound containing: an alkane triyl group of 1 to 30 carbon atoms; an alkylene group of 1 to 30 carbon atoms; and an alkali or alkaline earth metal group or an ammonium group.

  1. ASSESSMENT OF HYDROCARBON SEEPAGE DETECTION METHODS ON THE FORT PECK RESERVATION, NORTHEAST MONTANA

    SciTech Connect

    Lawrence M. Monson

    2003-06-30

    Surface exploration techniques have been employed in separate study areas on the Fort Peck Reservation in northeastern Montana. Anomalies associated with hydrocarbon seepage are documented in all three areas and a variety of surface exploration techniques can be compared. In a small area with established production, Head Gas and Thermal Desorption methods best match production; other methods also map depletion. In a moderate-size area that has prospects defined by 3D seismic data, Head Gas along with Microbial, Iodine, and Eh soil anomalies are all associated with the best hydrocarbon prospect. In a large area that contains many curvilinear patterns observed on Landsat images, that could represent micro-seepage chimneys, results are inconclusive. Reconnaissance mapping using Magnetic Susceptibility has identified a potential prospect; subsequent Soil Gas and Head Gas surveys suggest hydrocarbon potential. In the final year of this project the principle contractor, the Fort Peck Tribes, completed a second survey in the Wicape 3D Seismic Prospect Area (also known as Area 6 in Phase I of the project) and sampled several Landsat image features contained in the Smoke Creek Aeromag Anomaly Area (also known as Area 1 in Phase II of the project). Methods determined to be most useful in Phases I and II, were employed in this final Phase III of the study. The Southwest Wicape seismic anomaly was only partially confirmed. The abundant curvilinears proposed to be possible hydrocarbon micro-seepage chimneys in the Smoke Creek Area were not conclusively verified as such. Insufficient sampling of background data precludes affirmative identification of these mostly topographic Landsat features as gas induced soil and vegetation anomalies. However relatively higher light gas concentrations were found associated with some of the curvilinears. Based on the findings of this work the Assiniboine & Sioux Tribes of the Fort Peck Reservation intend to utilize surface hydrocarbon

  2. Long life hydrocarbon conversion catalyst and method of making

    DOEpatents

    Tonkovich, Anna Lee Y [Pasco, WA; Wang, Yong [Richland, WA; Gao, Yufei [Kennewick, WA

    2002-11-12

    The present invention includes a catalyst that has at least four layers, (1) porous support, (2) buffer layer, (3) interfacial layer, and optionally (4) catalyst layer. The buffer layer provides a transition of thermal expansion coefficient from the porous support to the interfacial layer thereby reducing thermal expansion stress as the catalyst is heated to high operating temperatures. The method of the present invention for making the at least three layer catalyst has the steps of (1) selecting a porous support, (2) solution depositing an interfacial layer thereon, and optionally (3) depositing a catalyst material onto the interfacial layer; wherein the improvement comprises (4) depositing a buffer layer between the porous support and the interfacial layer.

  3. Method And Apparatus For Converting Hydrocarbon Fuel Into Hydrogen Gas And Carbon Dioxide

    DOEpatents

    Clawson, Lawrence G.; Mitchell, William L.; Bentley, Jeffrey M.; Thijssen, Johannes H. J.

    2001-03-27

    A hydrocarbon fuel reforming method is disclosed suitable for producing synthesis hydrogen gas from reactions with hydrocarbons fuels, oxygen, and steam. A first mixture of an oxygen-containing gas and a first fuel is directed into a first tube 108 to produce a first reaction reformate. A second mixture of steam and a second fuel is directed into a second tube 116 annularly disposed about the first tube 108 to produce a second reaction reformate. The first and second reaction reformates are then directed into a reforming zone 144 and subject to a catalytic reforming reaction. In another aspect of the method, a first fuel is combusted with an oxygen-containing gas in a first zone 108 to produce a reformate stream, while a second fuel under steam reforming in a second zone 116. Heat energy from the first zone 108 is transferred to the second zone 116.

  4. Method for simultaneous recovery of hydrogen from water and from hydrocarbons

    DOEpatents

    Willms, R. Scott

    1996-01-01

    Method for simultaneous recovery of hydrogen and hydrogen isotopes from water and from hydrocarbons. A palladium membrane, when utilized in cooperation with a nickel catalyst in a reactor, has been found to drive reactions such as water gas shift, steam reforming and methane cracking to substantial completion by removing the product hydrogen from the reacting mixture. In addition, ultrapure hydrogen is produced, thereby eliminating the need for an additional processing step.

  5. Method for producing hydrocarbon fuels and fuel gas from heavy polynuclear hydrocarbons by the use of molten metal halide catalysts

    DOEpatents

    Gorin, Everett

    1979-01-01

    In a process for hydrocracking heavy polynuclear carbonaceous feedstocks to produce lighter hydrocarbon fuels by contacting the heavy feedstocks with hydrogen in the presence of a molten metal halide catalyst in a hydrocracking zone, thereafter separating at least a major portion of the lighter hydrocarbon fuels from the spent molten metal halide and thereafter regenerating the spent molten metal halide by incinerating the spent molten metal halide by combustion of carbon and sulfur compounds in the spent molten metal halide in an incineration zone, the improvement comprising: (a) contacting the heavy feedstocks and hydrogen in the presence of the molten metal halide in the hydrocracking zone at reaction conditions effective to convert from about 60 to about 90 weight percent of the feedstock to lighter hydrocarbon fuels; (b) separating at least a major portion of the lighter hydrocarbon fuels from the spent molten metal halide; (c) contacting the spent molten metal halide with oxygen in a liquid phase gasification zone at a temperature and pressure sufficient to vaporize from about 25 to about 75 weight percent of the spent metal halide, the oxygen being introduced in an amount sufficient to remove from about 60 to about 90 weight percent of the carbon contained in the spent molten metal halide to produce a fuel gas and regenerated metal halide; and (d) incinerating the spent molten metal halide by combusting carbon and sulfur compounds contained therein.

  6. The hydrocarbon accumulations mapping in crystalline rocks by mobile geophysical methods

    NASA Astrophysics Data System (ADS)

    Nesterenko, A.

    2013-05-01

    Sedimentary-migration origin theory of hydrocarbons dominates nowadays. However, a significant amount of hydrocarbon deposits were discovered in the crystalline rocks, which corroborates the theory of non-organic origin of hydrocarbons. During the solving of problems of oil and gas exploration in crystalline rocks and arrays so-called "direct" methods can be used. These methods include geoelectric methods of forming short-pulsed electromagnetic field (FSPEF) and vertical electric-resonance sounding (VERS) (FSPEF-VERS express-technology). Use of remote Earth sounding (RES) methods is also actual. These mobile technologies are extensively used during the exploration of hydrocarbon accumulations in crystalline rocks, including those within the Ukrainian crystalline shield. The results of explorations Four anomalous geoelectric zones of "gas condensate reservoir" type were quickly revealed as a result of reconnaissance prospecting works (Fig. 1). DTA "Obukhovychi". Anomaly was traced over a distance of 4 km. Approximate area is 12.0 km2. DTA"Korolevskaya". Preliminary established size of anomalous zone is 10.0 km2. The anomalous polarized layers of gas and gas-condensate type were determined. DTA "Olizarovskaya". Approximate size of anomaly is about 56.0 km2. This anomaly is the largest and the most intense. DTA "Druzhba". Preliminary estimated size of anomaly is 16.0 km2. Conclusions Long experience of a successful application of non-classical geoelectric methods for the solving of variety of practical tasks allow one to state their contribution to the development of a new paradigm of geophysical researches. Simultaneous usage of the remote sensing data processing and interpretation method and FSPEF and VERS technologies can essentially optimize and speed up geophysical work. References 1. S.P. Levashov. Detection and mapping of anomalies of "hydrocarbon deposit" type in the fault zones of crystalline arrays by geoelectric methods. / S.P. Levashov, N.A. Yakymchuk, I

  7. Precision gravimetric survey at the conditions of urban agglomerations

    NASA Astrophysics Data System (ADS)

    Sokolova, Tatiana; Lygin, Ivan; Fadeev, Alexander

    2014-05-01

    Large cities growth and aging lead to the irreversible negative changes of underground. The study of these changes at the urban area mainly based on the shallow methods of Geophysics, which extensive usage restricted by technogenic noise. Among others, precision gravimetry is allocated as method with good resistance to the urban noises. The main the objects of urban gravimetric survey are the soil decompaction, leaded to the rocks strength violation and the karst formation. Their gravity effects are too small, therefore investigation requires the modern high-precision equipment and special methods of measurements. The Gravimetry division of Lomonosov Moscow State University examin of modern precision gravimeters Scintrex CG-5 Autograv since 2006. The main performance characteristics of over 20 precision gravimeters were examined in various operational modes. Stationary mode. Long-term gravimetric measurements were carried at a base station. It shows that records obtained differ by high-frequency and mid-frequency (period 5 - 12 hours) components. The high-frequency component, determined as a standard deviation of measurement, characterizes the level of the system sensitivity to external noise and varies for different devices from 2 to 5-7 μGals. Midrange component, which closely meet to the rest of nonlinearity gravimeter drifts, is partially compensated by the equipment. This factor is very important in the case of gravimetric monitoring or observations, when midrange anomalies are the target ones. For the examined gravimeters, amplitudes' deviations, associated with this parameter may reach 10 μGals. Various transportation modes - were performed by walking (softest mode), lift (vertical overload), vehicle (horizontal overloads), boat (vertical plus horizontal overloads) and helicopter. The survey quality was compared by the variance of the measurement results and internal convergence of series. The measurement results variance (from ±2 to ±4 μGals) and its

  8. Method for recovery of viscous hydrocarbons by electromagnetic heating in situ

    SciTech Connect

    Sresty, G.C.; Bridges, J.E.; Dev, H.; Snow, R.H.

    1984-12-04

    A method of electromagnetic heating in situ recovers liquid hydrocarbons from an earth formation containing viscous hydrocarbonaceous liquid and water in an inorganic matrix where the formation is substantially impermeable to fluids under native conditions. A block of earth formation is substantially uniformly heated with electromagnetic power to a temperature at which the viscous hydrocarbonaceous liquid is relatively fluid and a portion of the water vaporizes to water vapor at a pressure sufficient to overcome the capillary pressure of the liquid in the matrix. Water vapor thereupon escaping from the block under such pressure is recovered with hydrocarbonaceous liquid driven thereby. The magnitude of the electromagnetic power is controlled to limit the current recovery ratio of water vapor to hydrocarboneous liquid below a predetermined limit assuring substantial recovery of the hydrocarbonaceous liquid prior to the driving off of substantially all the water.

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

    SciTech Connect

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

    2014-01-14

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

  10. Method of upgrading oils containing hydroxyaromatic hydrocarbon compounds to highly aromatic gasoline

    DOEpatents

    Baker, E.G.; Elliott, D.C.

    1993-01-19

    The present invention is a multi-stepped method of converting an oil which is produced by various biomass and coal conversion processes and contains primarily single and multiple ring hydroxyaromatic hydrocarbon compounds to highly aromatic gasoline. The single and multiple ring hydroxyaromatic hydrocarbon compounds in a raw oil material are first deoxygenated to produce a deoxygenated oil material containing single and multiple ring aromatic compounds. Then, water is removed from the deoxygenated oil material. The next step is distillation to remove the single ring aromatic compounds as gasoline. In the third step, the multiple ring aromatics remaining in the deoxygenated oil material are cracked in the presence of hydrogen to produce a cracked oil material containing single ring aromatic compounds. Finally, the cracked oil material is then distilled to remove the single ring aromatics as gasoline.

  11. Method of upgrading oils containing hydroxyaromatic hydrocarbon compounds to highly aromatic gasoline

    DOEpatents

    Baker, Eddie G.; Elliott, Douglas C.

    1993-01-01

    The present invention is a multi-stepped method of converting an oil which is produced by various biomass and coal conversion processes and contains primarily single and multiple ring hydroxyaromatic hydrocarbon compounds to highly aromatic gasoline. The single and multiple ring hydroxyaromatic hydrocarbon compounds in a raw oil material are first deoxygenated to produce a deoxygenated oil material containing single and multiple ring aromatic compounds. Then, water is removed from the deoxygenated oil material. The next step is distillation to remove the single ring aromatic compouns as gasoline. In the third step, the multiple ring aromatics remaining in the deoxygenated oil material are cracked in the presence of hydrogen to produce a cracked oil material containing single ring aromatic compounds. Finally, the cracked oil material is then distilled to remove the single ring aromatics as gasoline.

  12. Comparison of gravimetric and spectroscopic approaches to quantify stratum corneum removed by tape-stripping.

    PubMed

    Mohammed, D; Yang, Q; Guy, R H; Matts, P J; Hadgraft, J; Lane, M E

    2012-09-01

    Skin surface tape-stripping is an extensively used technique to examine the distribution profile, penetration and safety of various active compounds. It is also a widely accepted method to probe skin barrier properties and more specifically, those of the stratum corneum (SC). The amount of SC removed by tape-stripping is generally determined either gravimetrically or by extraction and measurement of SC proteins. A novel infra-red densitometry (IRD) technique has recently been introduced to measure SC protein content. In the present study, IRD was investigated as an alternative method to measure the mass of SC removed by tape-stripping. Tape-stripping experiments were conducted on human volunteers. The weight of the stratum corneum removed was assessed by the gravimetric approach and by IRD. Transepidermal water loss (TEWL) was also measured before and after each tape-strip. A linear correlation coefficient was obtained for the data from the gravimetric and IRD measurements (r(2)=0.65; n=240). IRD is therefore proposed as a rapid, non-destructive alternative to the gravimetric approach to estimate the amount of SC removed by tape-stripping in vivo. PMID:22713518

  13. Gravimetric Determination of Calcium as Calcium Carbonate Hydrate.

    ERIC Educational Resources Information Center

    Henrickson, Charles H.; Robinson, Paul R.

    1979-01-01

    The gravimetric determination of calcium as calcium carbonate is described. This experiment is suitable for undergraduate quantitative analysis laboratories. It is less expensive than determination of chloride as silver chloride. (BB)

  14. Oxygenated hydrocarbons in ambient air: Methods and measurements using solid-phase microextraction

    SciTech Connect

    Zhou, J.; McLaren, R.

    1999-07-01

    A method is described for the measurement of oxygenated and aromatic hydrocarbons in ambient air that combines the use of solid-phase microextraction with GC-MS. The method has proven to be sensitive enough to measure a range of species above the detection limit at urban and rural locations. Advantages and disadvantages of the method are discussed following the discussion of calibration and measurement methods. Measured mixing ratios are reported for oxygenated and aromatic hydrocarbons in the urban city of Toronto and at a rural forested site in Borden, Ontario. Correlations between different species are used to identify possible sources. At the Borden site, measurements at two levels on a tower through the forest canopy are used to discuss possible sources of species at that site. A unifying theme for both sites is the observation of similar and high median levels of methanol, acetone and acetaldehyde. The comparison of data from the urban and forested sites in this study do not provide evidence for a significant biogenic source of methanol as seen in the southern USA, although it is not discounted.

  15. Description of heat flux measurement methods used in hydrocarbon and propellant fuel fires at Sandia.

    SciTech Connect

    Nakos, James Thomas

    2010-12-01

    The purpose of this report is to describe the methods commonly used to measure heat flux in fire applications at Sandia National Laboratories in both hydrocarbon (JP-8 jet fuel, diesel fuel, etc.) and propellant fires. Because these environments are very severe, many commercially available heat flux gauges do not survive the test, so alternative methods had to be developed. Specially built sensors include 'calorimeters' that use a temperature measurement to infer heat flux by use of a model (heat balance on the sensing surface) or by using an inverse heat conduction method. These specialty-built sensors are made rugged so they will survive the environment, so are not optimally designed for ease of use or accuracy. Other methods include radiometers, co-axial thermocouples, directional flame thermometers (DFTs), Sandia 'heat flux gauges', transpiration radiometers, and transverse Seebeck coefficient heat flux gauges. Typical applications are described and pros and cons of each method are listed.

  16. Reaction Mechanism of Oxygen Atoms with Unsaturated Hydrocarbons by the Crossed-Molecular-Beams Method

    DOE R&D Accomplishments Database

    Buss, R. J.; Baseman, R. J.; Guozhong, H.; Lee, Y. T.

    1982-04-01

    From a series of studies of the reaction of oxygen atoms with unsaturated hydrocarbons using the crossed molecular beam method, the dominant reaction mechanisms were found to be the simple substitution reactions with oxygen atoms replacing H, Cl, Br atom or alkyl groups. Complication due to secondary reaction was avoided by carrying out experiments under single collisions and observing primary products directly. Primary products were identified by measuring the angular and velocity distributions of products at all the mass numbers which could be detected by the mass spectrometer, and from comparison of these distributions, applying the requirement of energy and momentum conservation.

  17. A simple method for calculating growth rates of petroleum hydrocarbon plumes.

    PubMed

    Bekins, Barbara A; Cozzarelli, Isabelle M; Curtis, Gary P

    2005-01-01

    Consumption of aquifer Fe(III) during biodegradation of ground water contaminants may result in expansion of a contaminant plume, changing the outlook for monitored natural attenuation. Data from two research sites contaminated with petroleum hydrocarbons show that toluene and xylenes degrade under methanogenic conditions, but the benzene and ethylbenzene plumes grow as aquifer Fe(III) supplies are depleted. By considering a one-dimensional reaction front in a constant unidirectional flow field, it is possible to derive a simple expression for the growth rate of a benzene plume. The method balances the mass flux of benzene with the Fe(III) content of the aquifer, assuming that the biodegradation reaction is instantaneous. The resulting expression shows that the benzene front migration is retarded relative to the ground water velocity by a factor that depends on the concentrations of hydrocarbon and bioavailable Fe(III). The method provides good agreement with benzene plumes at a crude oil study site in Minnesota and a gasoline site in South Carolina. Compared to the South Carolina site, the Minnesota site has 25% higher benzene flux but eight times the Fe(III), leading to about one-sixth the expansion rate. Although it was developed for benzene, toluene, ethylbenzene, and xylenes, the growth-rate estimation method may have applications to contaminant plumes from other persistent contaminant sources. PMID:16324003

  18. A simple method for calculating growth rates of petroleum hydrocarbon plumes

    USGS Publications Warehouse

    Bekins, B.A.; Cozzarelli, I.M.; Curtis, G.P.

    2005-01-01

    Consumption of aquifer Fe(III) during biodegradation of ground water contaminants may result in expansion of a contaminant plume, changing the outlook for monitored natural attenuation. Data from two research sites contaminated with petroleum hydrocarbons show that toluene and xylenes degrade under methanogenic conditions, but the benzene and ethylbenzene plumes grow as aquifer Fe(III) supplies are depleted. By considering a one-dimensional reaction front in a constant unidirectional flow field, it is possible to derive a simple expression for the growth rate of a benzene plume. The method balances the mass flux of benzene with the Fe(III) content of the aquifer, assuming that the biodegradation reaction is instantaneous. The resulting expression shows that the benzene front migration is retarded relative to the ground water velocity by a factor that depends on the concentrations of hydrocarbon and bioavailable Fe(III). The method provides good agreement with benzene plumes at a crude oil study site in Minnesota and a gasoline site in South Carolina. Compared to the South Carolina site, the Minnesota site has 25% higher benzene flux but eight times the Fe(III), leading to about one-sixth the expansion rate. Although it was developed for benzene, toluene, ethylbenzene, and xylenes, the growth-rate estimation method may have applications to contaminant plumes from other persistent contaminant sources. Copyright ?? 2005 National Ground Water Association.

  19. Matrix solid phase dispersion method for determination of polycyclic aromatic hydrocarbons in moss.

    PubMed

    Concha-Graña, Estefanía; Muniategui-Lorenzo, Soledad; De Nicola, Flavia; Aboal, Jesús R; Rey-Asensio, Ana Isabel; Giordano, Simonetta; Reski, Ralf; López-Mahía, Purificación; Prada-Rodríguez, Darío

    2015-08-01

    In this work a matrix solid-phase dispersion extraction method, followed by programmed temperature vaporization-gas chromatography-tandem mass spectrometry determination is proposed for the analysis of polycyclic aromatic hydrocarbons (PAHs) in moss samples. A devitalized, cultivated Sphagnum palustre L. moss clone obtained from the "Mossclone" EU-FP7 Project was used for the optimization and validation of the proposed method. Good trueness (84-116%), precision (intermediate precision lower than 11%) and sensitivity (quantitation limits lower than 1.7ngg(-1)) were obtained. The proposed method was compared with other procedures applied for this complex matrix, achieving a considerable reduction of sample amount, solvent volume and time consumption. The procedure was successfully tested for the analysis of PAHs in exposed moss clone samples for the monitoring of air pollution. Finally, the method was also tested for its suitability in the analysis of PAHs in other moss species as well as a lichen species. PMID:26105781

  20. Does mode mixing matter in EMD-based highlight volume methods for hydrocarbon detection? Experimental evidence

    NASA Astrophysics Data System (ADS)

    Xue, Ya-juan; Cao, Jun-xing; Du, Hao-kun; Zhang, Gu-lan; Yao, Yao

    2016-09-01

    Empirical mode decomposition (EMD)-based spectral decomposition methods have been successfully used for hydrocarbon detection. However, mode mixing that occurs during the sifting process of EMD causes the 'true' intrinsic mode function (IMF) to be extracted incorrectly and blurs the physical meaning of the IMF. We address the issue of how the mode mixing influences the EMD-based methods for hydrocarbon detection by introducing mode-mixing elimination methods, specifically ensemble EMD (EEMD) and complete ensemble EMD (CEEMD)-based highlight volumes, as feasible tools that can identify the peak amplitude above average volume and the peak frequency volume. Three schemes, that is, using all IMFs, selected IMFs or weighted IMFs, are employed in the EMD-, EEMD- and CEEMD-based highlight volume methods. When these methods were applied to seismic data from a tight sandstone gas field in Central Sichuan, China, the results demonstrated that the amplitude anomaly in the peak amplitude above average volume captured by EMD, EEMD and CEEMD combined with Hilbert transforms, whether using all IMFs, selected IMFs or weighted IMFs, are almost identical to each other. However, clear distinctions can be found in the peak frequency volume when comparing results generated using all IMFs, selected IMFs, or weighted IMFs. If all IMFs are used, the influence of mode mixing on the peak frequency volume is not readily discernable. However, using selected IMFs or a weighted IMFs' scheme affects the peak frequency in relation to the reservoir thickness in the EMD-based method. Significant improvement in the peak frequency volume can be achieved in EEMD-based highlight volumes using selected IMFs. However, if the weighted IMFs' scheme is adopted (i.e., if the undesired IMFs are included with reduced weights rather than excluded from the analysis entirely), the CEEMD-based peak frequency volume provides a more accurate reservoir thickness estimate compared with the other two methods. This

  1. Culture-Dependent and -Independent Methods Capture Different Microbial Community Fractions in Hydrocarbon-Contaminated Soils

    PubMed Central

    Stefani, Franck O. P.; Bell, Terrence H.; Marchand, Charlotte; de la Providencia, Ivan E.; El Yassimi, Abdel; St-Arnaud, Marc; Hijri, Mohamed

    2015-01-01

    Bioremediation is a cost-effective and sustainable approach for treating polluted soils, but our ability to improve on current bioremediation strategies depends on our ability to isolate microorganisms from these soils. Although culturing is widely used in bioremediation research and applications, it is unknown whether the composition of cultured isolates closely mirrors the indigenous microbial community from contaminated soils. To assess this, we paired culture-independent (454-pyrosequencing of total soil DNA) with culture-dependent (isolation using seven different growth media) techniques to analyse the bacterial and fungal communities from hydrocarbon-contaminated soils. Although bacterial and fungal rarefaction curves were saturated for both methods, only 2.4% and 8.2% of the bacterial and fungal OTUs, respectively, were shared between datasets. Isolated taxa increased the total recovered species richness by only 2% for bacteria and 5% for fungi. Interestingly, none of the bacteria that we isolated were representative of the major bacterial OTUs recovered by 454-pyrosequencing. Isolation of fungi was moderately more effective at capturing the dominant OTUs observed by culture-independent analysis, as 3 of 31 cultured fungal strains ranked among the 20 most abundant fungal OTUs in the 454-pyrosequencing dataset. This study is one of the most comprehensive comparisons of microbial communities from hydrocarbon-contaminated soils using both isolation and high-throughput sequencing methods. PMID:26053848

  2. Aromatic hydrocarbons of mineral oil origin in foods: method for determining the total concentration and first results.

    PubMed

    Biedermann, Maurus; Fiselier, Katell; Grob, Koni

    2009-10-14

    An online normal phase high-performance liquid chromatography (HPLC)-gas chromatography (GC)-flame ionization detection (FID) method was developed for the determination of the total concentration of the aromatic hydrocarbons of mineral oil origin with up to at least five rings in edible oils and other foods. For some samples, the olefins in the food matrix were epoxidized to increase their polarity and remove them from the fraction of the aromatic hydrocarbons. This reaction was carefully optimized, because also some aromatics tend to react. To reach a detection limit of around 1 mg kg(-1) in edible oils, an off-line enrichment was introduced. Some foods contained elevated concentrations of white paraffin oils (free of aromatics), but the majority of the mineral oils detected in foods were of technical grade with 20-30% aromatic hydrocarbons. Many foods contained mineral aromatic hydrocarbons in excess of 1 mg kg(-1). PMID:19728727

  3. Interpretation of Gravimetric and Aeromagnetic Data of the Tecoripa Chart in Southeast Sonora, Mexico.

    NASA Astrophysics Data System (ADS)

    Martínez-Retama, S.; Montaño-Del Cid, M. A.

    2015-12-01

    The Tecoripa chart H12-D64 is located southeast of the state of Sonora, México, south of Arizona. The geology is represented by sedimentary rocks of the Ordovician and Triassic, volcanic rocks of the Upper Cretaceous and Tertiary, intrusive rocks from the Upper Cretaceous- Tertiary and sedimentary rocks of the Cenozoic. In this paper a gravimetric study was conducted to determine the configuration and depth of the basement and to develop a structural model of the subsurface. For this purpose a consistent gravimetric survey in 3 profiles was conducted. To complement this study, gravimetric data obtained by INEGI (96 gravimetric stations spaced every 4000 m) that correspond to a regional survey was also used. The two sets of data were corrected and processed with the WinGLink software. The profiles were then modeled using the Talwani method. 4 Profiles corresponding to the gravimetric survey and 5 data profiles from INEGI were modeled. Aeromagnetic data from the total field of Tecoripa chart were also processed. The digital information was integrated and processed by generating a data grid. Processes applied to data consisted of reduction to the pole, regional-residual separation and upward continuations. In general, the obtained structural models show intrusive bodies associated with well-defined high gravimetric and magnetic and low gravimetric and magnetic are associated with basins and sedimentary rocks. The obtained geological models show the basement represented by volcanic rocks of the Tarahumara Formation from the Upper Cretaceous which are in contact with sedimentary rocks from the Barranca Group from Upper Cretaceous and limestones from the Middle Ordovician. Both volcanic and sedimentary rocks are intruded by granodiorite- granite with ages of the Tertiary-Oligocene. Based on the superficial geology as well as in the configuration of the basement and the obtained structural model the existence of faults with NW-SE orientation that originate Horst and

  4. A Review on Prediction Methods for Molar Enthalpies of Vaporization of Hydrocarbons: The ELBA Method as the Best Answer

    NASA Astrophysics Data System (ADS)

    Santos, Rui C.; Leal, João P.

    2012-12-01

    A review on prediction methods for molar enthalpies of vaporization at T = 298.15 K of hydrocarbons is presented. A new method is proposed and compared with six of the most common used ones from the literature. This new method, the extended Laidler bond additivity (ELBA), was applied to the prediction of standard molar enthalpies of vaporization of hydrocarbons (alkanes, alkenes, alkynes, polyenes, poly-ynes, cycloalkanes, cycloalkenes, benzene compounds, biphenyl compounds, and polyphenyl compounds) at T = 298.15 K. A total of 260 experimental standard molar enthalpies of vaporization at T = 298.15 K were used for the parameters optimization. Comparison between the experimental values and those calculated using ELBA led to an average absolute difference of 0.35 kJ mol-1, corresponding to an average relative error of 0.92%. In addition, this new method proves to be better than the ones used for comparison with an independent set of 83 experimental standard molar enthalpies of vaporization at T = 298.15 K.

  5. Field studies: Test method for on-line continuous measurement of total hydrocarbons (THC) and non-methane hydrocarbons (NMHC) in stack gas

    SciTech Connect

    Hsiao, H.H.; Lai, C.C.; Chu, H.W.; Cheng, H.

    1999-07-01

    A new method for on-line monitoring of total hydrocarbons and non-methane hydrocarbons in stack gas simultaneously was developed in this study. Based on the principle of on-line GC/FID, the method was developed and can be considered as a new modification of the Method 25 and 25A of US EPA. Major advantages of the method included (1) capability of distinguishing methane as Method 25; (2) near-real-time results; (3) broad species coverage; (4) monitoring methane in straightforward manner; (5) low operation and maintenance costs. In the proposed method, test samples were continuously pumped from detection sources and loaded with a two-loop sampling valve. The samples were then injected into two GC columns-empty and molecular sieve columns. The empty column was used for detection of THC, and the molecular sieve column was for methane. The detector in this GC was FID. NMHC concentration was obtained by subtracting methane from THC. The tests were carried out to measure the THC and methane in waste gas in various industries, including surface coating, semiconductor manufacturing, synthetic leather industries. Recovery rates of THC in the samples were between 86% to 114% for about 100 m of transfer line of samples. For the standard gas, the recovery rate was about 101%, 6.6 % of measurement precision, and 88%--114% of accuracy. The results showed the promising and reliable measurement of the test method for THC and methane in waste gas.

  6. An analytical method of predicting Lee-Kesler-Ploecker binary interaction coefficients: Part 1, For non-polar hydrocarbon mixtures

    SciTech Connect

    Sand, J.R.

    1994-12-31

    An analytical method is proposed for finding numerical values of binary interaction coefficients for non-polar hydrocarbon mixtures when the Lee-Kesler (LK) equation of state is applied. The method is based on solving simultaneous equations, which are Ploecker`s mixing rules for pseudocritical parameters of a mixture, and the Lee-Kesler equation for the saturation line. For a hydrocarbon mixture, the method allows prediction of {kappa}{sub ij} interaction coefficients (ICs) which are close to values obtained by processing experimental p-v-t data on the saturation line and subsequent averaging. For mixtures of hydrocarbon molecules containing from 2 to 9 carbon atoms, the divergence between calculated and experimentally based ICs is no more than {plus_minus}0.4%. The possibility of extending application of this method to other non-polar substances is discussed.

  7. Systems and methods for optically measuring properties of hydrocarbon fuel gases

    DOEpatents

    Adler-Golden, Steven; Bernstein, Lawrence S.; Bien, Fritz; Gersh, Michael E.; Goldstein, Neil

    1998-10-13

    A system and method for optical interrogation and measurement of a hydrocarbon fuel gas includes a light source generating light at near-visible wavelengths. A cell containing the gas is optically coupled to the light source which is in turn partially transmitted by the sample. A spectrometer disperses the transmitted light and captures an image thereof. The image is captured by a low-cost silicon-based two-dimensional CCD array. The captured spectral image is processed by electronics for determining energy or BTU content and composition of the gas. The innovative optical approach provides a relatively inexpensive, durable, maintenance-free sensor and method which is reliable in the field and relatively simple to calibrate. In view of the above, accurate monitoring is possible at a plurality of locations along the distribution chain leading to more efficient distribution.

  8. Systems and methods for optically measuring properties of hydrocarbon fuel gases

    DOEpatents

    Adler-Golden, S.; Bernstein, L.S.; Bien, F.; Gersh, M.E.; Goldstein, N.

    1998-10-13

    A system and method for optical interrogation and measurement of a hydrocarbon fuel gas includes a light source generating light at near-visible wavelengths. A cell containing the gas is optically coupled to the light source which is in turn partially transmitted by the sample. A spectrometer disperses the transmitted light and captures an image thereof. The image is captured by a low-cost silicon-based two-dimensional CCD array. The captured spectral image is processed by electronics for determining energy or BTU content and composition of the gas. The innovative optical approach provides a relatively inexpensive, durable, maintenance-free sensor and method which is reliable in the field and relatively simple to calibrate. In view of the above, accurate monitoring is possible at a plurality of locations along the distribution chain leading to more efficient distribution. 14 figs.

  9. Development of an Efficient Bacterial Consortium for the Potential Remediation of Hydrocarbons from Contaminated Sites

    PubMed Central

    Patowary, Kaustuvmani; Patowary, Rupshikha; Kalita, Mohan C.; Deka, Suresh

    2016-01-01

    The intrinsic biodegradability of hydrocarbons and the distribution of proficient degrading microorganisms in the environment are very crucial for the implementation of bioremediation practices. Among others, one of the most favorable methods that can enhance the effectiveness of bioremediation of hydrocarbon-contaminated environment is the application of biosurfactant producing microbes. In the present study, the biodegradation capacities of native bacterial consortia toward total petroleum hydrocarbons (TPH) with special emphasis to poly aromatic hydrocarbons were determined. The purpose of the study was to isolate TPH degrading bacterial strains from various petroleum contaminated soil of Assam, India and develop a robust bacterial consortium for bioremediation of crude oil of this native land. From a total of 23 bacterial isolates obtained from three different hydrocarbons contaminated samples five isolates, namely KS2, PG1, PG5, R1, and R2 were selected as efficient crude oil degraders with respect to their growth on crude oil enriched samples. Isolates KS2, PG1, and R2 are biosurfactant producers and PG5, R1 are non-producers. Fourteen different consortia were designed involving both biosurfactant producing and non-producing isolates. Consortium 10, which comprises two Bacillus strains namely, Bacillus pumilus KS2 and B. cereus R2 (identified by 16s rRNA sequencing) has shown the best result in the desired degradation of crude oil. The consortium showed degradation up to 84.15% of TPH after 5 weeks of incubation, as revealed from gravimetric analysis. FTIR (Fourier transform infrared) and GCMS (Gas chromatography-mass spectrometer) analyses were correlated with gravimetric data which reveals that the consortium has removed a wide range of petroleum hydrocarbons in comparison with abiotic control including different aliphatic and aromatic hydrocarbons. PMID:27471499

  10. Development of an Efficient Bacterial Consortium for the Potential Remediation of Hydrocarbons from Contaminated Sites.

    PubMed

    Patowary, Kaustuvmani; Patowary, Rupshikha; Kalita, Mohan C; Deka, Suresh

    2016-01-01

    The intrinsic biodegradability of hydrocarbons and the distribution of proficient degrading microorganisms in the environment are very crucial for the implementation of bioremediation practices. Among others, one of the most favorable methods that can enhance the effectiveness of bioremediation of hydrocarbon-contaminated environment is the application of biosurfactant producing microbes. In the present study, the biodegradation capacities of native bacterial consortia toward total petroleum hydrocarbons (TPH) with special emphasis to poly aromatic hydrocarbons were determined. The purpose of the study was to isolate TPH degrading bacterial strains from various petroleum contaminated soil of Assam, India and develop a robust bacterial consortium for bioremediation of crude oil of this native land. From a total of 23 bacterial isolates obtained from three different hydrocarbons contaminated samples five isolates, namely KS2, PG1, PG5, R1, and R2 were selected as efficient crude oil degraders with respect to their growth on crude oil enriched samples. Isolates KS2, PG1, and R2 are biosurfactant producers and PG5, R1 are non-producers. Fourteen different consortia were designed involving both biosurfactant producing and non-producing isolates. Consortium 10, which comprises two Bacillus strains namely, Bacillus pumilus KS2 and B. cereus R2 (identified by 16s rRNA sequencing) has shown the best result in the desired degradation of crude oil. The consortium showed degradation up to 84.15% of TPH after 5 weeks of incubation, as revealed from gravimetric analysis. FTIR (Fourier transform infrared) and GCMS (Gas chromatography-mass spectrometer) analyses were correlated with gravimetric data which reveals that the consortium has removed a wide range of petroleum hydrocarbons in comparison with abiotic control including different aliphatic and aromatic hydrocarbons. PMID:27471499

  11. A detailed gravimetric geoid from North America to Eurasia

    NASA Technical Reports Server (NTRS)

    Vincent, S. F.; Strange, W. E.; Marsh, J. G.

    1972-01-01

    A detailed gravimetric geoid of the United States, North Atlantic, and Eurasia, which was computed from a combination of satellite derived and surface gravity data, is presented. The precision of this detailed geoid is + or - 2 to + or - 3 m in the continents but may be in the range of 5 to 7 m in those areas where data is sparse. Comparisons of the detailed gravimetric geoid with results of Rapp, Fischer, and Rice for the United States, Bomford in Europe, and Heiskanen and Fischer in India are presented. Comparisons are also presented with geoid heights from satellite solutions for geocentric station coordinates in North America, the Caribbean, and Europe.

  12. Seismic and gravimetric monitoring of deep creep in rock slopes

    NASA Astrophysics Data System (ADS)

    Brückl, E.; Pregesbauer, M.; Ullrich, C.

    2003-04-01

    Deep creep of rock slopes is frequently observed in high mountain areas. Over a time span of some thousand years many of these slopes developed according the pattern of a "Sackung" and obtained a stable equilibrium at present. However, there are also examples of deep creep changing unexpectedly to a rapid and catastrophic sliding motion. The intention of the seismic and gravimetric monitoring presented here is dedicated to the prediction of this change from deep creep to rapid sliding. During IDNDR several mass movements were investigated in Austria by geodetic (Brunner et. al., 2000), geophysical (Brückl, 2001) and remote sensing methods (Rott et. al., 2000). For the monitoring program we selected two of these rock slopes, which represent deep creep in an active and rather early state (Gradenbach, Carinthia and Hochmais-Atemskopf, Tyrol). Even there is no imminent danger, we cannot exclude a transition to a rapid and catastrophic rock slide for these slopes in future time. The two rock slopes are also monitored by geodetic methods by other organizations. Deep creep in rock slopes is accompanied by the development of cracks and may generate low magnitude earthquakes. The monitoring of these events supplies significant and unique information about the state and process of deep creep. The monitoring time we realized on the two rock slopes (Gradenbach and Hochmais-Atemskopf) comprises a total of 30 d with up to 10 seismic stations. At an average about one event per day was detected and localized. Magnitudes and seismic moments of the events and their pattern in space-time will be shown. Irreversible displacements associated with the seismic events are compared with the displacements measured by geodetic methods and the seismic efficiency is estimated. The ground water level belongs to the most important factors influencing the process of deep creep in rock slopes. Although it can be measured in boreholes, there are good reasons to develop and apply appropriate

  13. Hydrocarbon pneumonia

    MedlinePlus

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

  14. Evaluation of gravimetric techniques to estimate the microvascular filtration coefficient.

    PubMed

    Dongaonkar, R M; Laine, G A; Stewart, R H; Quick, C M

    2011-06-01

    Microvascular permeability to water is characterized by the microvascular filtration coefficient (K(f)). Conventional gravimetric techniques to estimate K(f) rely on data obtained from either transient or steady-state increases in organ weight in response to increases in microvascular pressure. Both techniques result in considerably different estimates and neither account for interstitial fluid storage and lymphatic return. We therefore developed a theoretical framework to evaluate K(f) estimation techniques by 1) comparing conventional techniques to a novel technique that includes effects of interstitial fluid storage and lymphatic return, 2) evaluating the ability of conventional techniques to reproduce K(f) from simulated gravimetric data generated by a realistic interstitial fluid balance model, 3) analyzing new data collected from rat intestine, and 4) analyzing previously reported data. These approaches revealed that the steady-state gravimetric technique yields estimates that are not directly related to K(f) and are in some cases directly proportional to interstitial compliance. However, the transient gravimetric technique yields accurate estimates in some organs, because the typical experimental duration minimizes the effects of interstitial fluid storage and lymphatic return. Furthermore, our analytical framework reveals that the supposed requirement of tying off all draining lymphatic vessels for the transient technique is unnecessary. Finally, our numerical simulations indicate that our comprehensive technique accurately reproduces the value of K(f) in all organs, is not confounded by interstitial storage and lymphatic return, and provides corroboration of the estimate from the transient technique. PMID:21346245

  15. Determination of Phosphates by the Gravimetric Quimociac Technique

    ERIC Educational Resources Information Center

    Shaver, Lee Alan

    2008-01-01

    The determination of phosphates by the classic quimociac gravimetric technique was used successfully as a laboratory experiment in our undergraduate analytical chemistry course. Phosphate-containing compounds are dissolved in acid and converted to soluble orthophosphate ion (PO[subscript 4][superscript 3-]). The soluble phosphate is easily…

  16. 40 CFR 1065.290 - PM gravimetric balance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false PM gravimetric balance. 1065.290 Section 1065.290 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Pm Measurements § 1065.290 PM...

  17. 40 CFR 1065.290 - PM gravimetric balance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false PM gravimetric balance. 1065.290 Section 1065.290 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Pm Measurements § 1065.290 PM...

  18. 40 CFR 1065.290 - PM gravimetric balance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false PM gravimetric balance. 1065.290 Section 1065.290 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Pm Measurements § 1065.290 PM...

  19. 40 CFR 1065.290 - PM gravimetric balance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false PM gravimetric balance. 1065.290 Section 1065.290 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Pm Measurements § 1065.290 PM...

  20. 40 CFR 1065.290 - PM gravimetric balance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false PM gravimetric balance. 1065.290 Section 1065.290 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Pm Measurements § 1065.290 PM...

  1. Decomposition of Copper (II) Sulfate Pentahydrate: A Sequential Gravimetric Analysis.

    ERIC Educational Resources Information Center

    Harris, Arlo D.; Kalbus, Lee H.

    1979-01-01

    Describes an improved experiment of the thermal dehydration of copper (II) sulfate pentahydrate. The improvements described here are control of the temperature environment and a quantitative study of the decomposition reaction to a thermally stable oxide. Data will suffice to show sequential gravimetric analysis. (Author/SA)

  2. Method of preparing and utilizing a catalyst system for an oxidation process on a gaseous hydrocarbon stream

    DOEpatents

    Berry, David A; Shekhawat, Dushyant; Smith, Mark; Haynes, Daniel

    2013-07-16

    The disclosure relates to a method of utilizing a catalyst system for an oxidation process on a gaseous hydrocarbon stream with a mitigation of carbon accumulation. The system is comprised of a catalytically active phase deposited onto an oxygen conducting phase, with or without supplemental support. The catalytically active phase has a specified crystal structure where at least one catalytically active metal is a cation within the crystal structure and coordinated with oxygen atoms within the crystal structure. The catalyst system employs an optimum coverage ratio for a given set of oxidation conditions, based on a specified hydrocarbon conversion and a carbon deposition limit. Specific embodiments of the catalyst system are disclosed.

  3. Sensitive method for the determination of nitrated polycyclic aromatic hydrocarbons in the human diet.

    PubMed

    Siegmund, Barbara; Weiss, Richard; Pfannhauser, Werner

    2003-01-01

    The presence of nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) as contaminants in foods is nowadays a legitimate cause of concern, as they are reported to be strong direct-acting mutagens and carcinogens that may pose a risk to human health. Nevertheless, their concentrations in foods are in the ultra-trace region. In this study, we present a very sensitive analytical method for the determination of this compound class in complex food matrices. Special emphasis was put on sample extraction and clean up. Recoveries of 75% could be obtained for 1- and 2-nitronaphthalene; for all other compounds investigated the recoveries were >/=94%. The determination of the compounds was performed by gas chromatography-mass spectrometry. The results show that the use of negative chemical ionization (NCI) increases the sensitivity by one order of magnitude in comparison to electron impact ionization (EI) (limits of detection 0.07-0.25 micro g kg(-1) for EI and 0.01-0.02 micro g kg(-1) for NCI). The influence of the sample matrix on the sensitivity of the method is demonstrated with extracts of a sample from a duplicate diet study. Due to the lack of a certified reference material the suitability of the method is demonstrated with pumpkin seed oil that was spiked with nitro-PAHs at two different concentration levels. PMID:12520455

  4. Characterization of polycyclic aromatic hydrocarbons (PAHs) on lime spray dryer (LSD) ash using different extraction methods.

    PubMed

    Sun, Ping; Weavers, Linda K; Taerakul, Panuwat; Walker, Harold W

    2006-01-01

    In this study, traditional Soxhlet, automatic Soxhlet and ultrasonic extraction techniques were employed to determine the speciation and concentration of polycyclic aromatic hydrocarbons (PAHs) on lime spray dryer (LSD) ash samples collected from the baghouse of a spreader stoker boiler. To test the efficiencies of different extraction methods, LSD ash samples were doped with a mixture of 16 US EPA specified PAHs to measure the matrix spike recoveries. The results showed that the spike recoveries of PAHs were different using these three extraction methods with dichloromethane (DCM) as the solvent. Traditional Soxhlet extraction achieved slightly higher recoveries than automatic Soxhlet and ultrasonic extraction. Different solvents including toluene, DCM:acetone (1:1 V/V) and hexane:acetone (1:1 V/V) were further examined to optimize the recovery using ultrasonic extraction. Toluene achieved the highest spike recoveries of PAHs at a spike level of 10 microg kg(-1). When the spike level was increased to 50 microg kg(-1), the spike recoveries of PAHs also correspondingly increased. Although the type and concentration of PAHs detected on LSD ash samples by different extraction methods varied, the concentration of each detected PAH was consistently low, at microg kg(-1) levels. PMID:15990154

  5. EVALUATION OF A METHOD FOR SAMPLING AND ANALYSIS OF NICOTINE AND POLYNUCLEAR AROMATIC HYDROCARBONS IN INDOOR AIR

    EPA Science Inventory

    A study was performed to determine whether one sampling system and one analytical method can be used to measure both polynuclear aromatic hydrocarbons (PAH) and nicotine. he PAH collection efficiencies for both XAD-2 and XAD-4 adsorbents are very similar, but the nicotine collect...

  6. Method for reducing the sulfur content of a sulfur-containing hydrocarbon stream

    DOEpatents

    Mahajan, Devinder

    2004-12-28

    The sulfur content of a liquid hydrocarbon stream is reduced under mild conditions by contracting a sulfur-containing liquid hydrocarbon stream with transition metal particles containing the transition metal in a zero oxidation state under conditions sufficient to provide a hydrocarbon product having a reduced sulfur content and metal sulfide particles. The transition metal particles can be produced in situ by adding a transition metal precursor, e.g., a transition metal carbonyl compound, to the sulfur-containing liquid feed stream and sonicating the feed steam/transition metal precursor combination under conditions sufficient to produce the transition metal particles.

  7. Investigations into a novel method for atmospheric polycyclic aromatic hydrocarbon monitoring.

    PubMed

    Forbes, Patricia B C; Rohwer, Egmont R

    2009-01-01

    A novel analytical method for atmospheric polycyclic aromatic hydrocarbons (PAHs) was developed based on laser induced fluorescence (LIF) of samples on quartz multi-channel polydimethylsiloxane traps. A tunable dye laser with a frequency doubling crystal provided the excitation radiation, and a double monochromator with a photomultiplier tube detected emitted fluorescence. The method allowed for the rapid (<5 min), cost effective analysis of samples. Those yielding interesting results could be further analysed by direct thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS, with limits of detection of approximately 0.3 ng m(-3)), as photodegradation was minimal (<10% over 5 min irradiation). Small amounts of naphthalene photodegradation products identified by TD-GC-MS after >15 min irradiation, included phenol, benzyl alcohol and phthalic anhydride. Without any signal optimization, a LIF detection limit of approximately 1 microg m(-3) was established for naphthalene using a diffusion tube (diffusion rate of 2 ng s(-1)) and 292 nm excitation. PMID:19345458

  8. Method for converting hydrocarbon fuel into hydrogen gas and carbon dioxide

    SciTech Connect

    Clawson, L.G.; Mitchell, W.L.; Bentley, J.M.; Thijssen, J.H.J.

    2000-07-04

    A method for converting hydrocarbon fuel into hydrogen gas and carbon dioxide within a reformer is disclosed. According to the method, a stream including an oxygen-containing gas is directed adjacent to a first vessel and the oxygen-containing gas is heated. A stream including unburned fuel is introduced into the oxygen-containing gas stream to form a mixture including oxygen-containing gas and fuel. The mixture of oxygen-containing gas and unburned fuel is directed tangentially into a partial oxidation reaction zone within the first vessel. The mixture of oxygen-containing gas and fuel is further directed through the partial oxidation reaction zone to produce a heated reformate stream including hydrogen gas and carbon monoxide. Steam may also be mixed with the oxygen-containing gas and fuel, and the reformate stream from the partial oxidation reaction zone directed into a steam reforming zone. High- and low-temperature shift reaction zones may be employed for further fuel processing.

  9. Method for converting hydrocarbon fuel into hydrogen gas and carbon dioxide

    SciTech Connect

    Clawson, Lawrence G.; Mitchell, William L.; Bentley, Jeffrey M.; Thijssen, Johannes H. J.

    2000-01-01

    A method for converting hydrocarbon fuel into hydrogen gas and carbon dioxide within a reformer 10 is disclosed. According to the method, a stream including an oxygen-containing gas is directed adjacent to a first vessel 18 and the oxygen-containing gas is heated. A stream including unburned fuel is introduced into the oxygen-containing gas stream to form a mixture including oxygen-containing gas and fuel. The mixture of oxygen-containing gas and unburned fuel is directed tangentially into a partial oxidation reaction zone 24 within the first vessel 18. The mixture of oxygen-containing gas and fuel is further directed through the partial oxidation reaction zone 24 to produce a heated reformate stream including hydrogen gas and carbon monoxide. Steam may also be mixed with the oxygen-containing gas and fuel, and the reformate stream from the partial oxidation reaction zone 24 directed into a steam reforming zone 26. High- and low-temperature shift reaction zones 64,76 may be employed for further fuel processing.

  10. A comprehensive two-dimensional gas chromatography method for analyzing extractable petroleum hydrocarbons in water and soil.

    PubMed

    Seeley, Stacy K; Bandurski, Steven V; Brown, Robert G; McCurry, James D; Seeley, John V

    2007-01-01

    A flow-switching two-dimensional gas chromatography (GCxGC) apparatus has been constructed that can operate at temperatures as high as 340 degrees C. This system is employed to analyze complex hydrocarbon mixtures such as diesel fuel, gas-oil, motor oil, and petroleum contaminated environmental samples. The GCxGC system generates two-dimensional chromatograms with minimal overlap between the aliphatic and aromatic regions This allows these compound classes to be independently quantitated without prior fractionation. The GCxGC system is used to analyze extracts of spiked water samples, wastewater, and soil. The accuracy of the method is compared to that of the Massachusetts Extractable Petroleum Hydrocarbons (MA EPH) method. The GCxGC system generates a quantitative accuracy similar to the MA EPH method for the analysis of spiked water samples. The GCxGC method and the MA EPH method generate comparable levels of total hydrocarbons when wastewater is analyzed, but the GCxGC method detects a significantly higher aromatic content and lower aliphatic content. Both the GCxGC method and MA EPH method measure comparable levels of aromatics in the soil samples. PMID:18078573

  11. Study of the profile of polycyclic aromatic hydrocarbons in atmospheric particles (PM 10) using multivariate methods

    NASA Astrophysics Data System (ADS)

    Dallarosa, Juliana Braga; Teixeira, Elba Calesso; Pires, Marçal; Fachel, Jandyra

    The scope of the present study is to identify and quantify the main sources of polycyclic aromatic hydrocarbons (PAHs) in the Candiota region, Rio Grande do Sul, Brazil. Four sampling sites at a distance of 50 km from the emission source were selected: Aceguá, Aeroporto, 8 de Agosto and Pedras Altas. Samples were collected from February 2001 to October 2001, using an HV PM 10 sampler for high volumes during a continuous period of 24 h every 15 days. The filters containing the particulate matter were extracted with dichloromethane in soxhlet and later analyzed by gas chromatography/mass spectrometry (GC/MS). The average concentrations of PAHs varied from 0.051 to 1.791 ng m -3. The analysis of their distribution amongst the main emission sources was done through the diagnosis of concentration ratios of PAHs, as well as using statistical methods like factor analysis. The statistical analysis separated the 13 compounds studied in 3 Factors, grouping under Factor 1 emissions from the combustion of coal and wood, under Factor 2 vehicular emissions from the combustion of diesel oil and gasoline and under Factor 3 emissions from unburned diesel oil and gasoline.

  12. Method and apparatus for converting hydrocarbon fuel into hydrogen gas and carbon dioxide

    DOEpatents

    Clawson, Lawrence G.; Mitchell, William L.; Bentley, Jeffrey M.; Thijssen, Johannes H.J.

    2000-01-01

    An apparatus and a method are disclosed for converting hydrocarbon fuel or an alcohol into hydrogen gas and carbon dioxide. The apparatus includes a first vessel having a partial oxidation reaction zone and a separate steam reforming reaction zone that is distinct from the partial oxidation reaction zone. The first vessel has a first vessel inlet at the partial oxidation reaction zone and a first vessel outlet at the steam reforming zone. The reformer also includes a helical tube extending about the first vessel. The helical tube has a first end connected to an oxygen-containing source and a second end connected to the first vessel at the partial oxidation reaction zone. Oxygen gas from an oxygen-containing source can be directed through the helical tube to the first vessel. A second vessel having a second vessel inlet and second vessel outlet is annularly disposed about the first vessel. The helical tube is disposed between the first vessel and the second vessel and gases from the first vessel can be directed through second vessel.

  13. Method And Apparatus For Converting Hydrocarbon Fuel Into Hydrogen Gas And Carbon Dioxide

    DOEpatents

    Clawson, Lawrence G.; Mitchell, William L.; Bentley, Jeffrey M.; Thijssen, Johannes H. J.

    2000-09-26

    A method is disclosed for synthesizing hydrogen gas from hydrocarbon fuel. A first mixture of steam and a first fuel is directed into a first tube 208 to subject the first mixture to a first steam reforming reaction in the presence of a first catalyst 214. A stream of oxygen-containing gas is pre-heated by transferring heat energy from product gases. A second mixture of the pre-heated oxygen-containing gas and a second fuel is directed into a second tube 218 disposed about the first tube 208 to subject the second mixture to a partial oxidation reaction and to provide heat energy for transfer to the first tube 208. A first reaction reformate from the first tube 208 and a second reaction reformate from the second tube 218 are directed into a third tube 224 disposed about the second tube 218 to subject the first and second reaction reformates to a second steam reforming reaction, wherein heat energy is transferred to the third tube 224 from the second tube 218.

  14. Detection of polycyclic aromatic hydrocarbons (PAHs) in raw menhaden fish oil using fluorescence spectroscopy: Method development.

    PubMed

    Pena, Edwin A; Ridley, Lauren M; Murphy, Wyatt R; Sowa, John R; Bentivegna, Carolyn S

    2015-09-01

    Raw menhaden fish oil was developed for biomonitoring polycyclic aromatic hydrocarbons (PAHs) using fluorescence spectroscopy. Menhaden (Genus Brevoortia) were collected in 2010 and/or 2011 from Delaware Bay, New Jersey, USA; James River, Virginia, USA; Vermillion Bay, Louisiana, USA (VBLA); and Barataria Bay, Louisiana, USA (BBLA). Barataria Bay, Louisiana received heavy oiling from the Deepwater Horizon oil spill. Method development included determining optimal wavelengths for PAH detection, fish oil matrix interferences, and influence of solvent concentration on extraction. Results showed that some fish oils contained high molecular weight PAH-like compounds in addition to other fluorescent compounds such as albumin and vitamin A and vitamin E. None of these naturally occurring compounds interfered with detection of high molecular weight PAHs. However, data suggested that the lipid component of fish oil was altering fluorescence spectra by supporting the formation of PAH excimers. For example, the most intense excitation wavelength for hydroxypyrene shifted from Ex285/Em430 to Ex340/Em430. Comparison of Deepwater Horizon crude oil and fish oil spectra indicated that some fish oils contained crude oil-like PAHs. Using wavelengths of Ex360/Em430, fish oil concentrations were calculated as 3.92 μg/g, 0.61 μg/g, and 0.14 μg/g for a Delaware Bay sample, BBLA 2011, and VBLA 2011, respectively. Overall, these results supported using menhaden fish oil to track PAH exposures spatially and temporally. PMID:25867932

  15. Correction factors for gravimetric measurement of peritumoural oedema in man.

    PubMed

    Bell, B A; Smith, M A; Tocher, J L; Miller, J D

    1987-01-01

    The water content of samples of normal and oedematous brain in lobectomy specimens from 16 patients with cerebral tumours has been measured by gravimetry and by wet and dry weighing. Uncorrected gravimetry underestimated the water content of oedematous peritumoural cortex by a mean of 1.17%, and of oedematous peritumoural white matter by a mean of 2.52%. Gravimetric correction equations calculated theoretically and from an animal model of serum infusion white matter oedema overestimate peritumoural white matter oedema in man, and empirical gravimetric error correction factors for oedematous peritumoural human white matter and cortex have therefore been derived. These enable gravimetry to be used to accurately determine peritumoural oedema in man. PMID:3268140

  16. A detailed gravimetric geoid of North America, Eurasia, and Australia

    NASA Technical Reports Server (NTRS)

    Vincent, S.; Strange, W. E.

    1972-01-01

    A detailed gravimetric geoid of North America, the North Atlantic, Eurasia, and Australia computed from a combination of satellite-derived and surface 1 x 1 gravity data, is presented. Using a consistent set of parameters, this geoid is referenced to an absolute datum. The precision of this detailed geoid is + or - 2 meters in the continents but may be in the range of 5 to 7 meters in those areas where data was sparse. Comparisons of the detailed gravimetric geoid with results of Rice for the United States, Bomford and Fischer in Eurasia, and Mather in Australia are presented. Comparisons are also presented with geoid heights from satellite solutions for geocentric station coordinates in North America, the Caribbean, Europe, and Australia.

  17. A New, Rapid, Precise and Sensitive Method for Chlorine Stable Isotope Analysis of Chlorinated Aliphatic Hydrocarbons

    NASA Astrophysics Data System (ADS)

    van Acker, M. R.; Shahar, A.; Young, E. D.; Coleman, M. L.

    2005-12-01

    Chlorinated aliphatic hydrocarbons (CAH) are recognized common groundwater contaminants. Because of their physico-chemical properties, their lifespan in groundwater is in the order of decades (Pankow and Cherry, 1996). Stable isotopes can play a role in determining the rate and extent of CAH attenuation (Slater, 2003). The use of chlorine has been hampered by the current time consuming and insensitive analytical methods. We present a new analytical procedure to measure chlorine stable isotope values using a gas chromatograph coupled to a multi-collector inductively coupled mass spectrometer (GC-MC-ICP-MS). The GC has a Porapack Q packed column. The carrier gas was helium and the temperature was constant at 160°C. The GC was coupled to the MC-ICP-MS by heated stainless steel tubing. Our high resolution spectra showed that 37Cl is free of its main interference 36Ar-H over a range of 0.004 amu. Two pure CAH, trichloroethene (TCE) and tetrachloroethene (PCE), were used for zero enrichment (sample relative to itself) and standard-sample difference measurements. Integrations and background corrections of transient signals were performed using Microsoft Excel after import of the raw data from the MC-ICPMS acquisition software. Zero enrichment tests with TCE and PCE yielded δ37Cl of -0.04±0.16‰ and -0.03±0.17‰, respectively, results for sample injections of 0.12 to 0.02 microliters. Accuracy was tested by injecting 0.24 microliters of a 50/50 mixture of TCE and PCE of known isotopic compositions as the difference between the two solvents was of paramount interest. The δ37Cl(TCE) value of PCE was -1.99±0.16‰. A highly satisfactory comparison with the conventional method is shown by published values for TCE and PCE, -2.04±0.12‰ and -0.30±0.14‰, respectively (Jendrzejewski et al., 2001), giving a δ37Cl(TCE) value for PCE of -2.34±0.18‰. These tests of the GC-MC-ICP-MS method showed that we can obtain reproducible and accurate Cl isotope values using an

  18. Removal of surfactants from hydrocarbons with alcohol

    SciTech Connect

    Aiello, R.P.; Poling, D.E.; Stefanidakis, G.

    1984-02-07

    A method is disclosed for removing hydrocarbon-soluble anionic surfactants from gasoline or kerosene boiling range hydrocarbons. The method comprises (a) contacting a hydrocarbon mixture containing surfactants with a lower alcohol which is miscible with the hydrocarbon mixture to extract the surfactants; (b) contacting the mixture with water or caustic solution to extract the lower alcohol and surfactants from the hydrocarbon mixture; (c) separating the water or caustic solution from the hydrocarbons; and (d) removing the hydrocarbons.

  19. A Simple Method for Estimation of Dielectric Constants and Polarizabilities of Nonpolar and Slightly Polar Hydrocarbons

    NASA Astrophysics Data System (ADS)

    Panuganti, Sai R.; Wang, Fei; Chapman, Walter G.; Vargas, Francisco M.

    2016-07-01

    Many of the liquids that are used as electrical insulators are nonpolar or slightly polar petroleum-derived hydrocarbons, such as the ones used for cable and/or transformer oils. In this work, semi-empirical expressions with no adjustable parameters for the dielectric constant and the polarizability of nonpolar and slightly polar hydrocarbons and their mixtures are proposed and validated. The expressions that were derived using the Vargas-Chapman One-Third rule require the mass density and the molecular weight of the substance of interest. The equations were successfully tested for various hydrocarbons and polymers with dipole moments <0.23 and densities from 500 to 1200 kg\\cdot hbox {m}^{-3}. The predictions are in good agreement with the experimental data in a wide range of temperatures and pressures. The proposed expressions eliminate the need of extensive experimental data and require less input parameters compared to existing correlations.

  20. Lidar differential method of sulphur-containing hydrocarbon ultralow-concentration detection

    NASA Astrophysics Data System (ADS)

    Charty, Pavel V.; Privalov, Vadim E.; Shemanin, Valery G.

    2002-02-01

    The detailed study of the influence degree of different pollutants on an environment requires differential pollution monitoring that nowadays becomes possible due to development of measuring instruments such as laser systems for remote sensing. Until recently pollution exhaust monitoring from petroleum sources was reduced to the hydrocarbons sum quantity. The hydrocarbons with the small contents of sulphur low permissible level (LPL) is equal to 5 mg/m3. Such approach did not reflect the real situation, since the chemical composition of exhaust was not taken into account.

  1. Sampling and analytical method development and hand wipe measurements of dermal exposures to polycyclic aromatic hydrocarbons.

    PubMed

    Boeniger, Mark; Neumeister, Charles; Booth-Jones, Angela

    2008-07-01

    This article describes the laboratory assessment of a hand and surface wipe sampling method for polycyclic aromatic hydrocarbons (PAHs). The analytical method employed extraction of the wipe samples into dimethyl sulfoxide (DMSO) and high-performance liquid chromatography (HPLC) flourometric detection of pyrene, a predominant PAH in used gasoline engine oils (UGEO). Recovery of pyrene was evaluated for two different sampling media by first contaminating the hands of a small number of volunteers with UGEO, followed by applying a small amount of corn oil to the palms, and by wiping the skin with a Whatman cellulostic filter paper or a polyester fabric wipe (i.e., Alpha wipes). In summary, using either Whatman or Alpha wipes, the mean recovery of pyrene from the UGEO that was applied to the hands and contained within three consecutive wipes was 69% and 54%, respectively. However, the relative recovery of the first to second wipe was on average 47% and 75% for the two media, respectively. These results indicate that the Alpha wipes were more efficient at recovering pyrene in the first wipe but less efficient overall when all three consecutive samples were included. Even though this sampling was performed in a controlled laboratory environment, the minimum and maximum amount of pyrene recovered in the individual composite samples using either method spanned a range of twofold. Overall, intra-and interpersonal variability, as measured by coefficient of variation, were 22% and 19%, respectively, and were not statistically different by type of media used. This method was used in a pilot field survey to sample the hands of 18 automotive repair technicians and 18 office workers. Detectable amounts of pyrene (>0.2 microg/sample) were found on the hands of 61% and 0% of these two groups, respectively, with the highest measured quantity equal to 1.06 microg. Samples from the upper surfaces of automobile motors were generally low to nondetectable (<0.027 microg/sample), while

  2. Apparatus and method for simultaneous recovery of hydrogen from water and from hydrocarbons

    DOEpatents

    Willms, R. Scott; Birdsell, Stephen A.

    2000-01-01

    Apparatus and method for simultaneous recovery of hydrogen from water and from hydrocarbon feed material. The feed material is caused to flow over a heated catalyst which fosters the water-gas shift reaction (H.sub.2 O+COH.sub.2 +CO.sub.2) and the methane steam reforming reaction (CH.sub.4 +H.sub.2 O3 H.sub.2 +CO). Both of these reactions proceed only to partial completion. However, by use of a Pd/Ag membrane which is exclusively permeable to hydrogen isotopes in the vicinity of the above reactions and by maintaining a vacuum on the permeate side of the membrane, product hydrogen isotopes are removed and the reactions are caused to proceed further toward completion. A two-stage palladium membrane reactor was tested with a feed composition of 28% CQ.sub.4, 35% Q.sub.2 O (where Q=H, D, or T), and 31% Ar in 31 hours of continuous operation during which 4.5 g of tritium were processed. Decontamination factors were found to increase with decreasing inlet rate. The first stage was observed to have a decontamination factor of approximately 200, while the second stage had a decontamination factor of 2.9.times.10.sup.6. The overall decontamination factor was 5.8.times.10.sup.8. When a Pt/.alpha.-Al.sub.2 O.sub.3 catalyst is employed, decoking could be performed without catalyst degradation. However, by adjusting the carbon to oxygen ratio of the feed material with the addition of oxygen, coking could be altogether avoided.

  3. A Monte Carlo simulation method for assessing biotransformation effects on groundwater fuel hydrocarbon plume lengths

    NASA Astrophysics Data System (ADS)

    McNab, Walt W.

    2001-02-01

    Biotransformation of dissolved groundwater hydrocarbon plumes emanating from leaking underground fuel tanks should, in principle, result in plume length stabilization over relatively short distances, thus diminishing the environmental risk. However, because the behavior of hydrocarbon plumes is usually poorly constrained at most leaking underground fuel tank sites in terms of release history, groundwater velocity, dispersion, as well as the biotransformation rate, demonstrating such a limitation in plume length is problematic. Biotransformation signatures in the aquifer geochemistry, most notably elevated bicarbonate, may offer a means of constraining the relationship between plume length and the mean biotransformation rate. In this study, modeled plume lengths and spatial bicarbonate differences among a population of synthetic hydrocarbon plumes, generated through Monte Carlo simulation of an analytical solute transport model, are compared to field observations from six underground storage tank (UST) sites at military bases in California. Simulation results indicate that the relationship between plume length and the distribution of bicarbonate is best explained by biotransformation rates that are consistent with ranges commonly reported in the literature. This finding suggests that bicarbonate can indeed provide an independent means for evaluating limitations in hydrocarbon plume length resulting from biotransformation.

  4. MODELS AND METHODS FOR PETROLEUM HYDROCARBON RISK ASSESSMENT: ONSITE, LUSTRISK, AND HSSM

    EPA Science Inventory

    U.S. EPA has developed three tiers of models for analysis of fuel releases from underground storage tank (UST) systems: 1) OnSite; 2) LUSTRisk, and 3) the Hydrocarbon Spill Screening Model (HSSM). The tiered approach to modeling allows users to select a model based upon the amoun...

  5. VEHICLE-RELATED HYDROCARBON SOURCE COMPOSITIONS FROM AMBIENT DATA: THE GRACE/SAFER METHOD

    EPA Science Inventory

    The composition of three volatile hydrocarbon sources (emissions from vehicles in motion, evaporation of whole gasoline, and gasoline headspace vapor) have been derived from 550 ambient, hourly concentration measurements of 37 C2 - C9 volatile organic compounds (VOC). he measurem...

  6. Subtask 1.20 - Development of Methods to Determine the Environmental Availability of PAHs, PCBs, and Petroleum Hydrocarbons

    SciTech Connect

    Steven Hawthorne

    2007-06-30

    Three methods to determine the bioavailability of polycyclic aromatic hydrocarbons were modified and developed for application to polychlorinated biphenyls (PCBs). Water/XAD desorption and selective supercritical fluid extraction methods were developed to determine the rapidly-released fraction of PCBs from contaminated soils and sediments. A method to determine PCBs in sediment pore water based on solid-phase microextraction was also developed that is capable of determining low pg/mL concentrations with water samples as small as 1.5 mL.

  7. EVALUATION OF EMISSION TEST METHODS FOR HALOGENATED HYDROCARBONS. VOLUME II. CH2CL2, CH3CCL3, CF2CLCFCL2, AND CH2BRCH2BR

    EPA Science Inventory

    A test method for halogenated hydrocarbons has been evaluated and information is provided for the user. Four compounds were investigated, methylene chloride, methyl chloroform, Freon 113 and ethylene dibromide. Cylinder gases used for calibration and auditing were tested for stab...

  8. BOREAS HYD-8 1994 Gravimetric Moss Moisture Data

    NASA Technical Reports Server (NTRS)

    Wang, Xuewen; Hall, Forrest G. (Editor); Knapp, David E. (Editor); Smith, David E. (Technical Monitor)

    2000-01-01

    The Boreal Ecosystem-Atmosphere Study (BOREAS) Hydrology (HYD)-8 team made measurements of surface hydrological processes that were collected at the Northern Study Area-Old Black Spruce (NSA-OBS) Tower Flux site in 1994 and at Joey Lake, Manitoba, to support its research into point hydrological processes and the spatial variation of these processes. The data collected may be useful in characterizing canopy interception, drip, throughfall, moss interception, drainage, evaporation, and capacity during the growing season at daily temporal resolution. This particular data set contains the gravimetric moss moisture measurements from June to September 1994. A nested spatial sampling plan was implemented to support research into spatial variations of the measured hydrological processes and ultimately the impact of these variations on modeled carbon and water budgets. These data are stored in tabular ASCII files. The HYD-08 1994 gravimetric moss moisture data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).

  9. BOREAS HYD-8 1996 Gravimetric Moss Moisture Data

    NASA Technical Reports Server (NTRS)

    Fernandes, Richard; Hall, Forrest G. (Editor); Knapp, David E. (Editor); Smith, David E. (Technical Monitor)

    2000-01-01

    The Boreal Ecosystem-Atmosphere Study (BOREAS) Hydrology (HYD)-8 team made measurements of surface hydrological processes that were collected at the southern study area-Old Black Spruce (SSA-OBS) Tower Flux site in 1996 to support its research into point hydrological processes and the spatial variation of these processes. Data collected may be useful in characterizing canopy interception, drip, throughfall, moss interception, drainage, evaporation, and capacity during the growing season at daily temporal resolution. This particular data set contains the gravimetric moss moisture measurements from July to August 1996. To collect these data, a nested spatial sampling plan was implemented to support research into spatial variations of the measured hydrological processes and ultimately the impact of these variations on modeled carbon and water budgets. These data are stored in ASCII text files. The HYD-08 1996 gravimetric moss moisture data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).

  10. Apparatus and methods for direct conversion of gaseous hydrocarbons to liquids

    DOEpatents

    Kong, Peter C.; Lessing, Paul A.

    2006-04-25

    A chemical reactor for direct conversion of hydrocarbons includes a dielectric barrier discharge plasma cell and a solid oxide electrochemical cell in fluid communication therewith. The discharge plasma cell comprises a pair of electrodes separated by a dielectric material and passageway therebetween. The electrochemical cell comprises a mixed-conducting solid oxide electrolyte membrane tube positioned between a porous cathode and a porous anode, and a gas inlet tube for feeding oxygen containing gas to the porous cathode. An inlet is provided for feeding hydrocarbons to the passageway of the discharge plasma cell, and an outlet is provided for discharging reaction products from the reactor. A packed bed catalyst may optionally be used in the reactor to increase efficiency of conversion. The reactor can be modified to allow use of a light source for directing ultraviolet light into the discharge plasma cell and the electrochemical cell.

  11. Method for forming a potential hydrocarbon sensor with low sensitivity to methane and CO

    DOEpatents

    Mukundan, Rangachary; Brosha, Eric L.; Garzon, Fernando

    2003-12-02

    A hydrocarbon sensor is formed with an electrolyte body having a first electrolyte surface with a reference electrode depending therefrom and a metal oxide electrode body contained within the electrolyte body and having a first electrode surface coplanar with the first electrolyte surface. The sensor was formed by forming a sintered metal-oxide electrode body and placing the metal-oxide electrode body within an electrolyte powder. The electrolyte powder with the metal-oxide electrode body was pressed to form a pressed electrolyte body containing the metal-oxide electrode body. The electrolyte was removed from an electrolyte surface above the metal-oxide electrode body to expose a metal-oxide electrode surface that is coplanar with the electrolyte surface. The electrolyte body and the metal-oxide electrode body were then sintered to form the hydrocarbon sensor.

  12. A method for measuring electrokinetic coefficients of porous media and its potential application in hydrocarbon exploration

    NASA Astrophysics Data System (ADS)

    Jiang, Y. G.; Shan, F. K.; Jin, H. M.; Zhou, L. W.; Sheng, Ping

    We have designed and constructed a compact cell to measure the electrokinetic coefficients in the frequency range of interest to hydrocarbon exploration, 20 to 100 Hz. Experimental results are presented on the frequency dependence of the electrokinetic coefficients, and dynamic permeability of a porous rock saturated with either 0.1 mole brine or transformer oil. In particular, the brine-saturated electro-osmosis coefficient is found to be two orders of magnitude larger than that saturated with transformer oil; whereas for the streaming potential the ratio of the two cases is in the reverse. These results, when combined with viscosity and electrical conductivity values, lead consistently to the fact that the electrokinetic Onsager coefficient of brine-saturated samples is three orders of magnitude larger than that of oil-saturated samples. This difference provides a strong motivation to further explore the potential application of electrokinetic Onsager coefficient as a hydrocarbon indicator.

  13. Novel Approach for Evaluating Secondary Organic Aerosol from Aromatic Hydrocarbons: Unified Method for Predicting Aerosol Composition and Formation.

    PubMed

    Li, Lijie; Tang, Ping; Nakao, Shunsuke; Kacarab, Mary; Cocker, David R

    2016-06-21

    Innovative secondary organic aerosol (SOA) composition analysis methods normalizing aerosol yield and chemical composition on an aromatic ring basis are developed and utilized to explore aerosol formation from oxidation of aromatic hydrocarbons. SOA yield and chemical composition are revisited using 15 years of University of California, Riverside/CE-CERT environmental chamber data on 17 aromatic hydrocarbons with HC:NO ranging from 11.1 to 171 ppbC:ppb. SOA yield is redefined in this work by normalizing the molecular weight of all aromatic precursors to the molecular weight of the aromatic ring [Formula: see text], where i is the aromatic hydrocarbon precursor. The yield normalization process demonstrates that the amount of aromatic rings present is a more significant driver of aerosol formation than the vapor pressure of the precursor aromatic. Yield normalization also provided a basis to evaluate isomer impacts on SOA formation. Further, SOA elemental composition is explored relative to the aromatic ring rather than on a classical mole basis. Generally, four oxygens per aromatic ring are observed in SOA, regardless of the alkyl substitutes attached to the ring. Besides the observed SOA oxygen to ring ratio (O/R ∼ 4), a hydrogen to ring ratio (H/R) of 6 + 2n is observed, where n is the number of nonaromatic carbons. Normalization of yield and composition to the aromatic ring clearly demonstrates the greater significance of aromatic ring carbons compared with alkyl carbon substituents in determining SOA formation and composition. PMID:27177154

  14. Method of generating hydrocarbon reagents from diesel, natural gas and other logistical fuels

    DOEpatents

    Herling, Darrell R.; Aardahl, Chris L.; Rozmiarek, Robert T.; Rappe, Kenneth G.; Wang, Yong; Holladay, Jamelyn D.

    2010-06-29

    The present invention provides a process for producing reagents for a chemical reaction by introducing a fuel containing hydrocarbons into a flash distillation process wherein the fuel is separated into a first component having a lower average molecular weight and a second component having a higher average molecular weight. The first component is then reformed to produce synthesis gas wherein the synthesis gas is reacted catalytically to produce the desire reagent.

  15. Method of Generating Hydrocarbon Reagents from Diesel, Natural Gas and Other Logistical Fuels

    DOEpatents

    Herling, Darrell R [Richland, WA; Aardahl, Chris L [Richland, WA; Rozmiarek, Robert T [Middleton, WI; Rappe, Kenneth G [Richland, WA; Wang, Yong [Richland, WA; Holladay, Jamelyn D [Kennewick, WA

    2008-10-14

    The present invention provides a process for producing reagents for a chemical reaction by introducing a fuel containing hydrocarbons into a flash distillation process wherein the fuel is separated into a first component having a lower average molecular weight and a second component having a higher average molecular weight. The first component is then reformed to produce synthesis gas wherein the synthesis gas is reacted catalytically to produce the desire reagent.

  16. Modelling of the density inhomogeneities with the geoid data (Gravimetric Tomography)

    NASA Astrophysics Data System (ADS)

    Greku, Rudolf

    2010-05-01

    models after procedure of the isostatic compensation are coordinated with the available seismic tomography models. Density inhomogeneities in the crust body and the sedimentary layers are discovered on the tomographic images. At the same time, a low radial resolution at large depths in the gravimetric tomography method does not allow to identify low velocity anomalous heterogeneity on the core-mantle boundary. However, there is a quite high lateral and radial resolution at the smaller depths. The EGM2008 geoid model shows more detail density distribution than the EGM96 geoid for the Ukrainian territory. Therefore, joint modelling of seismic and gravimetric tomography data may be fruitful. 1. Greku, R. Kh. and Greku, T. R. (2006), Mantle and crustal structure of Antarctic along 170°W and 44°E meridians with the gravimetric tomography technique, in: Terra Antarctica Reports, No. 12, pp 145-154, Terra Antarctica Publication, Siena, Italy; 2. Moritz H. 1990. The Figure of the Earth. Theoretical Geodesy and the Earth's Interior. Wichmann, Karlsruhe; 3. Ishii M. and J.Tromp (2001), Even-degree lateral variations in the Earth's mantle constrained by free oscillations and the free-air gravity anomaly, Geophys. J. Int., 145, 77-96; 5. Ishii M. and J.Tromp (2004), Constraining large-scale mantle heterogeneity using mantle and inner-core sensitive normal modes, Physics of the Earth and Planetary Interiors, 146, 113-124; 5. Ritzwoller, M. H., N. M. Shapiro, A. L. Levshin and G. M. Leahy (2001), Crustal and upper mantle structure beneath Antarctica and surrounding oceans, J. Geophys. Res., 106, 12, 30645-30670. 6. Turcotte, D. L. & Schubert, G. 2002. Geodynamics, 2nd ed. Pp. 456.

  17. Prediction of ecotoxicity of hydrocarbon-contaminated soils using physicochemical parameters

    SciTech Connect

    Wong, D.C.L.; Chai, E.Y.; Chu, K.K.; Dorn, P.B.

    1999-11-01

    The physicochemical properties of eight hydrocarbon-contaminated soils were used to predict toxicity to earthworms (Eisenia fetida) and plants. The toxicity of these preremediated soils was assessed using earthworm avoidance, survival, and reproduction and seed germination and root growth in four plant species. No-observed-effect and 25% inhibitory concentrations were determined from the earthworm and plant assays. Physical property measurements and metals analyses of the soils were conducted. Hydrocarbon contamination was characterized by total petroleum hydrocarbons, oil and grease, and GC boiling-point distribution. Univariate and multivariate statistical methods were used to examine relationships between physical and chemical properties and biological endpoints. Soil groupings based on physicochemical properties and toxicity from cluster and principal component analyses were generally similar. Correlation analysis identified a number of significant relationships between soil parameters and toxicity that were used in univariate model development. Total petroleum hydrocarbons by gas chromatography and polars were identified as predictors of earthworm avoidance and survival and seed germination, explaining 65 to 75% of the variation in the data. Asphaltenes also explained 83% of the variation in seed germination. Gravimetric total petroleum hydrocarbons explained 40% of the variation in earthworm reproduction, whereas 43% of the variation in plant root growth was explained by asphaltenes. Multivariate one-component partial least squares models, which identified predictors similar to those identified by the univariate models, were also developed for worm avoidance and survival and seed germination and had predictive powers of 42 and 29%, respectively.

  18. A rapid column technique for trapping and collecting of volatile fungal hydrocarbons and hydrocarbon derivatives.

    PubMed

    Booth, Eric; Strobel, Gary; Knighton, Berk; Sears, Joe; Geary, Brad; Avci, Recep

    2011-10-01

    A custom-made stainless steel column was designed to contain various materials that would trap the hydrocarbons and hydrocarbon derivatives during the processes of fungal fermentation ultimately yielding preparative amounts of volatile organic substances (VOCs). Trapping materials tested in the column were Carbotrap materials A and B (Supelco) as well as bentonite-shale from the oil bearing areas of Eastern Montana, the former allowed for the effective and efficient trapping of VOCs from purged cultures of Hypoxylon sp. Trapping efficiencies of various materials were measured by both gravimetric as well as proton transfer reaction mass spectroscopy with the Carbotraps A and B being 99% efficient when tested with known amounts of 1,8-cineole. Trapped fungal VOCs could effectively be removed and recovered via controlled heating of the stainless steel column followed by passage of the gases through a liquid nitrogen trap at a recovery rate of ca 65-70%. This method provides for the recovery of mg quantities of compounds normally present in the gas phase that may be needed for spectroscopy, bioassays and further separation and analysis and may have wide applicability for many other biological systems involving VOCs. Other available Carbotraps could be used for other applications. PMID:21660573

  19. Gravimetric Analysis of Particulate Matter using Air Samplers Housing Internal Filtration Capsules

    PubMed Central

    O'Connor, Sean; O'Connor, Paula Fey; Feng, H. Amy

    2015-01-01

    Summary An evaluation was carried out to investigate the suitability of polyvinyl chloride (PVC) internal capsules, housed within air sampling devices, for gravimetric analysis of airborne particles collected in workplaces. Experiments were carried out using blank PVC capsules and PVC capsules spiked with 0,1 – 4 mg of National Institute of Standards and Technology Standard Reference Material® (NIST SRM) 1648 (Urban Particulate Matter) and Arizona Road Dust (Air Cleaner Test Dust). The capsules were housed within plastic closed-face cassette samplers (CFCs). A method detection limit (MDL) of 0,075 mg per sample was estimated. Precision Sr at 0,5 - 4 mg per sample was 0,031 and the estimated bias was 0,058. Weight stability over 28 days was verified for both blanks and spiked capsules. Independent laboratory testing on blanks and field samples verified long-term weight stability as well as sampling and analysis precision and bias estimates. An overall precision estimate Ŝrt of 0,059 was obtained. An accuracy measure of ±15,5% was found for the gravimetric method using PVC internal capsules. PMID:26435581

  20. Combustion of viscous hydrocarbons

    SciTech Connect

    Hayes, M.E.; Hrebenar, K.R.; Murphy, P.L.; Futch, L.E. Jr.; Deal, J.F. III; Bolden, P.L. Jr.

    1987-08-04

    A method is described for utilizing viscous hydrocarbons as combustible pre-atomized fuels, comprising: (A) forming a hydrocarbon-in-water emulsion using an effective amount of a surfactant package comprising at least one water-soluble surfactant, the hydrocarbon-in-water emulsion (1) comprising a hydrocarbon characterized by API gravity of about 20/sup 0/ API or less, viscosity of about 1000 centipoise or greater at 212/sup 0/F., a paraffin content of about 50% by weight or less and, an aromatic content of about 15% by weight or greater, and (2) having a hydrocarbon water ratio from about 60:40 to about 90:10 by volume; and (B) burning the resultant hydrocarbon-in-water emulsion.

  1. A street deposit sampling method for metal and hydrocarbon contamination assessment.

    PubMed

    Bris, F J; Garnaud, S; Apperry, N; Gonzalez, A; Mouchel, J M; Chebbo, G; Thévenot, D R

    1999-09-01

    Urban surface contamination, by atmospheric deposits as well as human activities, is a major concern for urban pollution management. Besides coarse street deposits which are clearly perceived and easily removed, suspended solid (SS) surface loads and contamination by heavy metals and hydrocarbons are rarely assessed although they could be of major importance with regards to combined or separate server overflow (CSO and SSO) impacts. Both dry and wet vacuum sampling procedures have been first compared, in the laboratory, using dry and sieved clay or street deposits. Then the wet vacuum sampling procedure has been refined, coupling the injection of water and the hand-brushing of the surface prior to its vacuum cleaning, and evaluated on a car parking area close to the University. Finally this procedure has been assessed in Béarn Street within the 'Le Marais' district in Paris centre, and 34 samples have been analysed for metal and eight for aromatic hydrocarbon contamination. Heavy metal concentrations (0.1-1.7 g kg-1 dry wt. Cu, 0.9-6.1 g kg-1 dry wt. Pb and 1.5-4.6 g kg-1 dry wt. Zn) within street deposit samples collected in Paris centre, indicate a high contamination, especially for copper and zinc, as compared to reported data. Total polyaromatic hydrocarbons (PAHs) are in the 3-11 mg kg-1 dry wt. range, thus approximately 10 times less contaminated than dry atmospheric deposits. This paper presents data obtained and discusses the difficulties encountered when sampling street deposits in busy areas of a city like Paris. The water jet street cleaning procedure used by Paris city workers was tested for its efficiency, by comparison of surface loads before and after the cleaning procedure. Although solids cleaning efficiency is highly variable (20-65%) and somewhat higher for particles larger than 100 microns, particulate metal cleaning efficiency is even more variable (0-75%) and particulate PAHs appear not to be significantly removed. PMID:10535121

  2. Method and apparatus for separating wax/water from hydrocarbon mixture boiling in the lubricating oil range

    SciTech Connect

    Mintz, D.J.; Gleason, A.M.

    1986-04-08

    A method is described of separating wax particles and/or water droplets from a hydrocarbon oil mixture boiling in the lubricating oil range, in which mixture the wax/water forms a dispersion. The free excess electric charge which is net unipolar is introduced into the wax/water-containing oil mixture and the charged wax/water-containing oil mixture and at least one collector surface are brought into contact with one another so that the wax/water collects, due to the electrophoretic migration of the wax/water caused by the introduced electric charge, and accumulates on the collector surface(s).

  3. Development and validation of a cleanup method for hydrocarbon containing samples for the analysis of semivolatile organic compounds

    SciTech Connect

    Hoppe, E.W.; Stromatt, R.W.; Campbell, J.A.; Steele, M.J.; Jones, J.E.

    1992-04-01

    Samples obtained from the Hanford single shell tanks (SSTs) are contaminated with normal paraffin hydrocarbon (NPH) as hydrostatic fluid from the sampling process or can be native to the tank waste. The contamination is usually high enough that a dilution of up to several orders of magnitude may be required before the sample can be analyzed by the conventional gas chromatography/mass spectrometry methodology. This can prevent detection and measurement of organic constituents that are present at lower concentration levels. To eliminate or minimize the problem, a sample cleanup method has been developed and validated and is presented in this document.

  4. Use of two SPE-GC/MS methods for field isolation and quantitation of polycyclic aromatic hydrocarbons

    SciTech Connect

    Furlong, E.T.; Koleis, J.C.; Gates, P.M.

    1995-12-31

    Increasing sensitivity and subsequently improving method-detection limits for a variety of organic contaminant compounds is an ongoing effort in environmental analytical chemistry. Several field-deployable isolation techniques have been developed for concentrating hydrophobic organic contaminants from large (> 1 liter) volumes of aqueous samples. The capacity of large-volume solid-phase extraction (LV-SPE) was used as part of a simple, efficient, field-operable technique for isolating microgram-per-liter to nanogram-per-liter quantities of polycyclic aromatic hydrocarbons (PAH) in 4- to 8-liter ground-water samples from a petroleum- contaminated aquifer near Bemidji, Minn.

  5. Machine method for determining the presence and location of hydrocarbon deposits within a subsurface earth formation

    SciTech Connect

    Clavier, C.M.; Khatchikian, A.

    1983-09-06

    In accordance with illustrative embodiments of the present invention, techniques are shown for processing well logging data to provide improved results. More particularly, a technique is disclosed for determining the reliability of well logging computations. Another technique is disclosed for making a preliminary pass of the well logging data to automatically select certain input parameter. Still another technique is disclosed for automatically determining the minimum possible hydrocarbon density for each formation level. This last technique is contrasted with the prior art technique with set one minimum value for the entire length of a borehole.

  6. Hydrocarbon synthesis catalyst and method of preparation and use thereof. [DOE patent application

    SciTech Connect

    Sapienza, R.S.; Sansone, M.J.; Slegeir, W.A.R.

    1981-08-14

    A catalyst for the synthesis of hydrocarbons from carbon monoxide and hydrogen composed of palladium or platinum and cobalt supported on a solid phase is disclosed. The catalyst is prepared by heating a heterogeneous component of the palladium or platinum deposited on the solid support in a solution of cobalt carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable product fractions even with dilute gaseous reactants. The catalyst is preferably used in dilute slurry form, which is desirable from a heat transfer standpoint.

  7. BOREAS HYD-6 Ground Gravimetric Soil Moisture Data

    NASA Technical Reports Server (NTRS)

    Carroll, Thomas; Knapp, David E. (Editor); Hall, Forrest G. (Editor); Peck, Eugene L.; Smith, David E. (Technical Monitor)

    2000-01-01

    The Boreal Ecosystem-Atmosphere Study (BOREAS) Hydrology (HYD)-6 team collected several data sets related to the moisture content of soil and overlying humus layers. This data set contains percent soil moisture ground measurements. These data were collected on the ground along the various flight lines flown in the Southern Study Area (SSA) and Northern Study Area (NSA) during 1994 by the gamma ray instrument. The data are available in tabular ASCII files. The HYD-06 ground gravimetric soil moisture data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).

  8. Determination of soil moisture distribution from impedance and gravimetric measurements

    NASA Technical Reports Server (NTRS)

    Ungar, Stephen G.; Layman, Robert; Campbell, Jeffrey E.; Walsh, John; Mckim, Harlan J.

    1992-01-01

    Daily measurements of the soil dielectric properties at 5 and 10 cm were obtained at five locations throughout the First ISLSCP Field Experiment (FIFE) test site during the 1987 intensive field campaigns (IFCs). An automated vector voltmeter was used to monitor the complex electrical impedance, at 10 MHz, of cylindrical volumes of soil delineated by specially designed soil moisture probes buried at these locations. The objective of this exercise was to test the hypothesis that the soil impedance is sensitive to the moisture content of the soil and that the imaginary part (that is, capacitive reactance) can be used to calculate the volumetric water content of the soil. These measurements were compared with gravimetric samples collected at these locations by the FIFE staff science team.

  9. The gravimetric boundary value problem in spheroidal approximation

    NASA Astrophysics Data System (ADS)

    Panou, Georgios

    2015-04-01

    In this presentation the linear gravimetric boundary value problem is discussed in spheroidal approximation. The input to the problem is gravity disturbances, using the known Earth's topography as boundary and corresponds to an oblique derivative problem. From the physical viewpoint, it has many advantages and can serve as the basis in establishing a world vertical datum. Adopting the spheroidal approximation in this boundary value problem, an integral equation results which can be solved analytically using successive approximations. However, the mathematical model becomes simpler and can be solved more easily by applying certain permissible approximations: neglecting the Earth's topography, a spheroidal normal derivative (Neumann) problem is obtained. Under the spherical approximation, the result is a normal derivative problem plus suitable corrections. In this case, neglecting the Earth's topography, the solution corresponds to the well-known spherical Hotine integral. Finally, the relative errors in the above approximations and derivations are quantitatively estimated.

  10. A principal-component and least-squares method for allocating polycyclic aromatic hydrocarbons in sediment to multiple sources

    SciTech Connect

    Burns, W.A.; Mankiewicz, P.J.; Bence, A.E.; Page, D.S.; Parker, K.R.

    1997-06-01

    A method was developed to allocate polycyclic aromatic hydrocarbons (PAHs) in sediment samples to the PAH sources from which they came. The method uses principal-component analysis to identify possible sources and a least-squares model to find the source mix that gives the best fit of 36 PAH analytes in each sample. The method identified 18 possible PAH sources in a large set of field data collected in Prince William Sound, Alaska, USA, after the 1989 Exxon Valdez oil spill, including diesel oil, diesel soot, spilled crude oil in various weathering states, natural background, creosote, and combustion products from human activities and forest fires. Spill oil was generally found to be a small increment of the natural background in subtidal sediments, whereas combustion products were often the predominant sources for subtidal PAHs near sites of past or present human activity. The method appears to be applicable to other situations, including other spills.

  11. Evaluation of methods for simultaneous collection and determination of nicotine and polynuclear aromatic hydrocarbons in indoor air

    SciTech Connect

    Chuang, J.C.; Kuhlman, M.R.; Wilson, N.K.

    1990-01-01

    A study was performed to determine whether one sampling system and one analytical method can be used to measure both polynuclear aromatic hydrocarbons (PAH) and nicotine. The PAH collection efficiencies for both XAD-2 and XAD-4 adsorbents are very similar, but the nicotine collection efficiency was greater for XAD-4. The spiked perdeuterated PAH were retained well in both adsorbents after exposure to more than 300 cu m of air. A two-step Soxhlet extraction, dichloromethane followed by ethylacetate, was used to remove nicotine and PAH from XAD-4. The extract was analyzed by positive chemical ionization or electron impact gas chromatography/mass spectrometry (GC/MS) to determine nicotine and PAH. It is shown that one sampling system (quartz fiber filter and XAD-4 in series) and one analytical method (Soxhlet extraction and GC/MS) can be used to measure both nicotine and PAH in indoor air.

  12. Evaluation of methods for simultaneous collection and determination of nicotine and polynuclear aromatic hydrocarbons in indoor air

    SciTech Connect

    Chuang, J.C.; Kuhlman, M.R. ); Wilson, N.K. )

    1990-05-01

    A study was performed to determine whether one sampling system and one analytical method can be used to collect and measure both polynuclear aromatic hydrocarbons (PAHs) and nicotine. PAH collection efficiencies for both XAD-2 and XAD-4 adsorbents were very similar, but nicotine collection efficiency was greater for XAD-4. Spiked perdeuterated PAHs were retained well in both adsorbents after exposure to more than 300 m{sup 3} of air. A two-step Soxhlet extraction, dichloromethane followed by ethyl acetate, was used to remove nicotine and PAHs from XAD-4. The extract was analyzed by positive chemical ionization or electron impact gas chromatography/mass spectrometry (GC/MS) to determine nicotine and PAHs. It is shown that one sampling system (quartz fiber filter and XAD-4 in series) and one analytical method (Soxhlet extraction and GC/MS) can be used for both nicotine and PAHs in indoor.

  13. Airborne Gravity Data Enhances NGS Experimental Gravimetric Geoid in Alaska

    NASA Astrophysics Data System (ADS)

    Holmes, S. A.; Childers, V. A.; Li, X.; Roman, D. R.

    2014-12-01

    The U.S. National Geodetic Survey [NGS], through their Gravity for the Redefinition of the American Vertical Datum [GRAV-D] program, continues to update its gravimetry holdings by flying new airborne gravity surveys over a large fraction of the USA and its territories. By 2022, NGS intends that all orthometric heights in the USA will be determined in the field by using a reliable national gravimetric geoid model to transform from geodetic heights obtained from GPS. Several airborne campaigns have already been flown over Alaska and its coastline. Some of this Alaskan coastal data have been incorporated into a new NGS experimental geoid model - xGEOID14. The xGEOID14 model is the first in a series of annual experimental geoid models that will incorporate NGS GRAV-D airborne data. This series provides a useful benchmark for assessing and improving current techniques by which the airborne and land-survey data are filtered and cleaned, and then combined with satellite gravity models, elevation data (etc.) with the ultimate aim of computing a geoid model that can support a national physical height system by 2022. Here we will examine the NGS GRAV-D airborne data in Alaska, and assess its contribution to xGEOID14. Future prospects for xGEOID15 will also be considered.

  14. Gravimetric determination of the continental-oceanic boundary of the Argentine continental margin (from 36°S to 50°S)

    NASA Astrophysics Data System (ADS)

    Arecco, María Alejandra; Ruiz, Francisco; Pizarro, Guillermo; Giménez, Mario; Martínez, Patricia; Ramos, Víctor A.

    2016-01-01

    This paper presents the gravimetric analysis together with seismic data as an integral application in order to identify the continental-oceanic crust boundary (COB) of the Argentine continental margin from 36°S to 50°S in a continuous way. The gravimetric and seismic data are made up of large grids of data obtained from satellite altimetry and marine research. The methodology consists of three distinct methods: (i) the application of enhancement techniques to gravimetric anomalies, (ii) the calculation of crustal thinning from 3-D gravity inversion modelling of the crust-mantle discontinuity and (iii) 2-D gravimetric modelling supported by multichannel reflection and refraction seismic profiles. In the first method, the analytic signal, Theta map, and tilt angle and its horizontal derivative were applied. In the second method, crustal thickness was obtained as the difference in the depths of the crystalline basement and the crust-mantle discontinuity; the latter was obtained via gravimetric inversion. Finally, 2-D modelling was performed from free-air anomalies in two representative sections by considering as restriction surfaces those coming from the interpretation of seismic data. The results of the joint application of enhancement techniques and 2-D and 3-D modelling have enabled continuous interpretation of the COB. In this study, the COB was determined continuously from the integration of 2-D profiles of the enhancement techniques, taking account of crustal thickness and performing 2-D gravimetric modelling. The modelling technique was complemented by regional studies integrated with multichannel seismic reflection and seismic refraction lines, resulting in consistent enhancement techniques.

  15. Availability and leaching of polycyclic aromatic hydrocarbons: Controlling processes and comparison of testing methods.

    PubMed

    Roskam, Gerlinde D; Comans, Rob N J

    2009-01-01

    We have studied the availability and leaching of polycyclic aromatic hydrocarbons (PAHs) from two contaminated materials, a tar-containing asphalt granulate (Sigma16 US-EPA PAHs 3412mg/kg) and gasworks soil (SigmaPAHs 900mg/kg), by comparing results from three typical types of leaching tests: a column, sequential batch, and two different availability tests. The sequential batch test was found to largely resemble the column test. However, the leaching of particularly the larger PAHs (>5 aromatic rings) was found to be enhanced in the batch test by up to an order of magnitude, probably due to their association with large DOC (dissolved organic carbon) molecules generated by the vigorous mixing. The release of PAHs in the two availability tests, in which the leaching is facilitated by either a high concentration of DOC or Tenax resin, was similar, although the latter test was easier to perform and yielded more repeatable results. The availability was much higher than the amount leached in the column and sequential batch tests. However, biodegradation had apparently occurred in the column test and the total amount of PAHs released by either leaching or biodegradation, 9% and 26% for asphalt granulate and gasworks soil, respectively, did equal the amount leached in the availability tests. Therefore, the availability was found to provide a relevant measure of the PAH fraction that can be released from the solid phase. These results stress the importance of using the available instead of the total amount of contaminant in the risk analysis of solid materials in utilization or disposal. PMID:18554897

  16. A real-time polymerase chain reaction method for monitoring anaerobic, hydrocarbon-degrading bacteria based on a catabolic gene.

    PubMed

    Beller, Harry R; Kane, Staci R; Legler, Tina C; Alvarez, Pedro J J

    2002-09-15

    We have developed a real-time polymerase chain reaction (PCR) method that can quantify hydrocarbon-degrading bacteria in sediment samples based on a catabolic gene associated with the first step of anaerobic toluene and xylene degradation. The target gene, bssA, codes for the alpha-subunit of benzylsuccinate synthase. The primer-probe set for real-time PCR was based on consensus regions of bssA from four denitrifying bacterial strains; bssA sequences for two of these strains were determined during this study. The method proved to be sensitive (detection limit ca. 5 gene copies) and had a linear range of >7 orders of magnitude. We used the method to investigate how gasohol releases from leaking underground storage tanks could affect indigenous toluene-degrading bacteria. Microcosms inoculated with aquifer sediments from four different sites were incubated anaerobically with BTEX (benzene, toluene, ethylbenzene, and xylenes) and nitrate in the presence and absence of ethanol. Overall, population trends were consistent with observed toluene degradation activity: the microcosms with the most rapid toluene degradation also had the largest numbers of bssA copies. In the microcosms with the most rapid toluene degradation, numbers of bssA copies increased 100-to 1000-fold over the first 4 days of incubation, during which time most of the toluene had been consumed. These results were supported by slot blot analyses with unamplified DNA and by cloning and sequencing of putative bssA amplicons, which confirmed the real-time PCR method's specificity for bssA. Use of a companion real-time PCR method for estimating total eubacterial populations (based on 16S rDNA) indicated that, in some cases, ethanol disproportionately supported the growth of bacteria that did not contain bssA. The real-time PCR method for bssA could be a powerful tool for monitored natural attenuation of BTEX in fuel-contaminated groundwater. To our knowledge, this is the first reported molecular method that

  17. A High Throughput Method for Measuring Polycyclic Aromatic Hydrocarbons in Seafood Using QuEChERS Extraction and SBSE.

    PubMed

    Pfannkoch, Edward A; Stuff, John R; Whitecavage, Jacqueline A; Blevins, John M; Seely, Kathryn A; Moran, Jeffery H

    2015-01-01

    National Oceanic and Atmospheric Administration (NOAA) Method NMFS-NWFSC-59 2004 is currently used to quantitatively analyze seafood for polycyclic aromatic hydrocarbon (PAH) contamination, especially following events such as the Deepwater Horizon oil rig explosion that released millions of barrels of crude oil into the Gulf of Mexico. This method has limited throughput capacity; hence, alternative methods are necessary to meet analytical demands after such events. Stir bar sorptive extraction (SBSE) is an effective technique to extract trace PAHs in water and the quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction strategy effectively extracts PAHs from complex food matrices. This study uses SBSE to concentrate PAHs and eliminate matrix interference from QuEChERS extracts of seafood, specifically oysters, fish, and shrimp. This method provides acceptable recovery (65-138%) linear calibrations and is sensitive (LOD = 0.02 ppb, LOQ = 0.06 ppb) while providing higher throughput and maintaining equivalency between NOAA 2004 as determined by analysis of NIST SRM 1974b mussel tissue. PMID:25873967

  18. A High Throughput Method for Measuring Polycyclic Aromatic Hydrocarbons in Seafood Using QuEChERS Extraction and SBSE

    PubMed Central

    Pfannkoch, Edward A.; Stuff, John R.; Whitecavage, Jacqueline A.; Blevins, John M.; Seely, Kathryn A.; Moran, Jeffery H.

    2015-01-01

    National Oceanic and Atmospheric Administration (NOAA) Method NMFS-NWFSC-59 2004 is currently used to quantitatively analyze seafood for polycyclic aromatic hydrocarbon (PAH) contamination, especially following events such as the Deepwater Horizon oil rig explosion that released millions of barrels of crude oil into the Gulf of Mexico. This method has limited throughput capacity; hence, alternative methods are necessary to meet analytical demands after such events. Stir bar sorptive extraction (SBSE) is an effective technique to extract trace PAHs in water and the quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction strategy effectively extracts PAHs from complex food matrices. This study uses SBSE to concentrate PAHs and eliminate matrix interference from QuEChERS extracts of seafood, specifically oysters, fish, and shrimp. This method provides acceptable recovery (65–138%) linear calibrations and is sensitive (LOD = 0.02 ppb, LOQ = 0.06 ppb) while providing higher throughput and maintaining equivalency between NOAA 2004 as determined by analysis of NIST SRM 1974b mussel tissue. PMID:25873967

  19. Development of Hydrocarbon Flow Calibration Facility as a National Standard

    NASA Astrophysics Data System (ADS)

    Shimada, Takashi; Doihara, Ryouji; Terao, Yoshiya; Takamoto, Masaki

    A new primary standard for hydrocarbon flow measurements has been constructed at National Metrology Institute of Japan (NMIJ). The facility was designed for the calibration of hydrocarbon flowmeters in the flow rate range between 3 and 300 m3/h. The expanded uncertainty is estimated to be 0.03 % for volumetric flow rate and 0.02 % for mass flow rate (coverage factor: k = 2). The primary standard is based on a static and gravimetric method with a flying start and finish. The facility consists of two test rigs using kerosene and light oil as working fluids. The test lines for the flowmeters are 50, 100 and 150 mm in diameter and three servo positive displacement meters are used as working standards. To verify the calibration performance, a Coriolis flowmeter, a turbine meter and a positive displacement flowmeter have been calibrated at both test rigs. Furthermore, an international comparison with SP, Swedish National Testing Research Institute, was carried out. A screw-type positive displacement flowmeter was selected as the transfer standard and was calibrated at NMIJ and SP. The result shows that the two national standards at the two institutes agree within the quoted expanded uncertainties.

  20. Magnetic solid phase extraction and static headspace gas chromatography-mass spectrometry method for the analysis of polycyclic aromatic hydrocarbons.

    PubMed

    Cai, Ying; Yan, Zhihong; Wang, Lijia; NguyenVan, Manh; Cai, Qingyun

    2016-01-15

    A magnetic solid phase extraction (MSPE) protocol combining a static headspace gas chromatography coupled to mass spectrometry (HS-GC-MS) method has been developed for extraction, and determination of 16 polycyclic aromatic hydrocarbons (PAHs) in drinking water samples. Magnetic nanoparticles (MNPs) were coated with 3-aminopropyltriethoxysilane and modified by cholesterol chloroformate. Transmission electron microscope, vibrating sample magnetometer, Fourier transform infrared spectrometry and X-ray photoelectron spectroscopy were used to characterize the cholesterol-functionalized sorbents, and the main parameters affecting the extraction as well as HS sampling, such as sorbent amount, extraction time, oven temperature and equilibration time have been investigated and established. Combination with HS sampling, the MSPE procedure was simple, fast and environmentally friendly, without need of any organic solvent. Method validation proved the feasibility of the developed sorbents for the quantitation of the investigated analytes at trace levels obtaining the limit of detection (S/N=3) ranging from 0.20 to 7.8 ng/L. Good values for intra and inter-day precision were obtained (RSDs ≤ 9.9%). The proposed method was successfully applied to drinking water samples. PMID:26724892

  1. A new spectral deconvolution - selected ion monitoring method for the analysis of alkylated polycyclic aromatic hydrocarbons in complex mixtures.

    PubMed

    Robbat, Albert; Wilton, Nicholas M

    2014-07-01

    A new gas chromatography/mass spectrometry (GC/MS) method is proffered for the analysis of polycyclic aromatic hydrocarbons (PAH) and their alkylated homologs in complex samples. Recent work elucidated the fragmentation pathways of alkylated PAH, concluding that multiple fragmentation patterns per homolog (MFPPH) are needed to correctly identify all isomers. Programming the MS in selected ion monitoring (SIM) mode to detect homolog-specific MFPPH ions delivers the selectivity and sensitivity that the conventional SIM and/or full scan mass spectrometry methods fail to provide. New spectral deconvolution software eliminates the practice of assigning alkylated homolog peaks via pattern recognition within laboratory-defined retention windows. Findings show that differences in concentration by SIM/molecular ion detection of C1-C4 PAH, now the standard, yield concentration differences compared to SIM/MFPPH of thousands of percent for some homologs. The SIM/MFPPH methodology is also amenable to the analysis of polycyclic aromatic sulfur heterocycles (PASH) and their alkylated homologs, since many PASH have the same m/z ions as those of PAH and, thus, are false positives in SIM/1-ion PAH detection methods. PMID:24840423

  2. EVALUATION OF EPA METHOD 8120 FOR DETERMINATION OF CHLORINATED HYDROCARBONS IN ENVIRONMENTAL SAMPLES

    EPA Science Inventory

    Method 8120 of EPA Manual SW-846 has been evaluated in a single-laboratory study. Modifications made to the current method invlude expansion of the list of target compounds from 15 to 22; replacement of the packed gas chromatographic columns with 2 megabore fused-silica open tubu...

  3. Field test of a generic method for halogenated hydrocarbons. Report for September 1992-September 1993

    SciTech Connect

    Bursey, J.T.; Merrill, R.G.; McAllister, R.A.; McGaughey, J.F.

    1993-07-07

    The objective of the program was to perform a field validation of the VOST and SemiVOST methods as written at a coal fired power plant in a manner that will allow the collection of sufficient valid data to be able to establish the bias and precision of the methods for the halogenated organic compounds listed in Title III of the Clean Air Act Amendments of 1990. Pesticides, polychlorinated biphenyls, 2,3,7,8-tetrachloro-p-dibenzodioxin, and dibenzofurans were excluded from the study because EPA specific methods already exist for these compounds. To achieve this objective, a field test site was selected to allow access for the quadruple sampling trains required for testing. Collection and evaluation of the data followed one of the acceptable approaches detailed in the EPA Method 301.

  4. Remote detection of hydrocarbon seeps

    SciTech Connect

    Barringer, A. R.

    1985-05-14

    A method of detecting hydrocarbon seeps in a sea or in earth is disclosed. The method involves interrogating aerosols formed above the sea or earth surface with an intense beam of primary light radiation generated aboard an aircraft or other vehicle. The spectral composition of the beam is selected to induce secondary light radiation in certain hydrocarbon materials contained in aerosols generated by hydrocarbon seeps rising to the sea or earth surface. The secondary light radiation is detected aboard the aircraft and subjected to spectral analysis to determine whether the composition of the aerosols is characteristic of aerosols generated by hydrocarbon seeps. Apparatus for implementing the method is also disclosed.

  5. Oil and gas exploration system and method for detecting trace amounts of hydrocarbon gases in the atmosphere

    DOEpatents

    Wamsley, Paula R.; Weimer, Carl S.; Nelson, Loren D.; O'Brien, Martin J.

    2003-01-01

    An oil and gas exploration system and method for land and airborne operations, the system and method used for locating subsurface hydrocarbon deposits based upon a remote detection of trace amounts of gases in the atmosphere. The detection of one or more target gases in the atmosphere is used to indicate a possible subsurface oil and gas deposit. By mapping a plurality of gas targets over a selected survey area, the survey area can be analyzed for measurable concentration anomalies. The anomalies are interpreted along with other exploration data to evaluate the value of an underground deposit. The system includes a differential absorption lidar (DIAL) system with a spectroscopic grade laser light and a light detector. The laser light is continuously tunable in a mid-infrared range, 2 to 5 micrometers, for choosing appropriate wavelengths to measure different gases and avoid absorption bands of interference gases. The laser light has sufficient optical energy to measure atmospheric concentrations of a gas over a path as long as a mile and greater. The detection of the gas is based on optical absorption measurements at specific wavelengths in the open atmosphere. Light that is detected using the light detector contains an absorption signature acquired as the light travels through the atmosphere from the laser source and back to the light detector. The absorption signature of each gas is processed and then analyzed to determine if a potential anomaly exists.

  6. A novel and cost-effective method for the determination of fifteen polycyclic aromatic hydrocarbons in low volume rainwater samples.

    PubMed

    Fernández-Amado, M; Prieto-Blanco, M C; López-Mahía, P; Muniategui-Lorenzo, S; Prada-Rodríguez, D

    2016-08-01

    A novel single-step method was developed for the determination of 15 polycyclic aromatic hydrocarbons (PAHs) at ultratrace levels in rainwater by on-line in-tube solid-phase microextraction (IT-SPME) coupled to high-performance liquid chromatography-photodiode array-fluorescence detection. This paper is focused on a study of the IT-SPME coupling and optimization, its application to rainwater and other environmental waters and the stability of PAH rainwater solutions. In order to solve the different extractive behavior of PAHs, several IT-SPME parameters were optimized, with the type and percentage of organic modifier playing a decisive role. In the kinetic study on stability of PAH solutions, the organic modifier has proven to be effective as a preservative, avoiding the loss of the higher-molecular weight PAHs. The proposed method presents a wide interval of linearity (10-1500ngL(-1)) and a good relative standard deviation between 3.4% and 14.6% for the PAHs analyzed. Detection and quantification limits between 2.3 and 28ngL(-1) and 5.7 and 65ngL(-1) were obtained respectively, taking into account the values of the procedure blanks. Recoveries for different kinds of real water samples were within the range of 72-110%. Low and medium-molecular weight PAHs predominate in daily and monthly rainwater samples analyzed. In comparison with other methods reported, the proposed method achieves a significant reduction of the sample volume, the organic solvent consumption and time of sample treatment, allowing a cost-effective analysis of environmental waters. The method is especially suitable for samples from the precipitation events of low intensity or short duration for which sample volume is limiting. PMID:27216671

  7. Comparison of photoacoustic radiometry to gas chromatography/mass spectrometry methods for monitoring chlorinated hydrocarbons

    SciTech Connect

    Sollid, J.E.; Trujillo, V.L.; Limback, S.P.; Woloshun, K.A.

    1996-03-01

    A comparison of two methods of gas chromatography mass spectrometry (GCMS) and a nondispersive infrared technique, photoacoustic radiometry (PAR), is presented in the context of field monitoring a disposal site. First is presented an historical account describing the site and early monitoring to provide an overview. The intent and nature of the monitoring program changed when it was proposed to expand the Radiological Waste Site close to the Hazardous Waste Site. Both the sampling methods and analysis techniques were refined in the course of this exercise.

  8. Preparation of gravimetric standards for measurements of atmospheric oxygen and reevaluation of atmospheric oxygen concentration

    NASA Astrophysics Data System (ADS)

    Tohjima, Yasunori; Machida, Toshinobu; Watai, Tomonori; Akama, Isao; Amari, Taketo; Moriwaki, Yasushi

    2005-06-01

    Fourteen standard mixtures composed of ambient levels of CO2, Ar, O2, and N2 have been prepared in 10-L high-pressure aluminum cylinders by a gravimetric technique for atmospheric O2 measurements. A highly precise balance with a precision of 2.5 mg is used to determine the masses of individual components in the cylinders. To balance the buoyant forces on both sides of the balance beam during weighing the gravimetric standard cylinder, a same sized cylinder is placed on a pan on the opposite side of the beam. In addition, the cylinders of the gravimetric standards and a tare cylinder are alternately weighed to compensate for the drift of the zero-point of the balance. To determine the mole fractions accurately, the mass of each component is corrected for the buoyancy changes caused by the expansion of the cylinder, and the molecular masses of the source O2 and N2 gases are corrected for their isotopic compositions. The differences in the O2 mole fractions of the 14 gravimetric standards range about 100 ppm (μmol mol-1). The gravimetric mole fractions are compared with the analyzed values of CO2, Ar, O2 + Ar, and (O2 + Ar)/N2. The reproducibility of the gravimetric technique is determined from the standard deviations of the differences between the gravimetric and analyzed values, and is quantified as 15.5 per meg for the O2/N2 ratio and 2.9 ppm for the O2 mole fraction. The gravimetric scale is applied to the measurements from air samples collected at Hateruma Island, Japan. The average Ar mole fraction for the air samples collected from June 2003 through June 2004 is 9333 ± 2 ppm. On the basis of this Ar mole fraction, the annual average mole fractions of O2 and N2 in 2000 are evaluated to be 209392 ± 3 ppm and 780876 ± 2 ppm, respectively.

  9. DELINEATION OF SUBSURFACE HYDROCARBON CONTAMINANT DISTRIBUTION USING A DIRECT PUSH RESISTIVITY METHOD

    EPA Science Inventory

    A direct push resistivity method was evaluated as a complementary screening tool to provide rapid in-situ contaminant detection to aid in better defining locations for drilling, sampling, and monitoring well installation at hazardous waste sites. Nine continuous direct push resi...

  10. Method of viscosifying aqueous fluids and process for recovery of hydrocarbons from subterranean formations

    SciTech Connect

    Borchardt, J.K.

    1985-04-02

    The present invention relates to a method of viscosifying aqueous fluids and a viscosifying composition which when admixed with an aqueous fluid produces a viscosity increase in the fluid in excess of the additive viscosity of the individual composition components. The viscosifying composition comprises xanthan gum and at least one memeber selected from the group consisting of the ammonium, hydrogen or alkali metal salts of polystyrene sulfonate, polyvinyl sulfonate and hydrolyzed copolymers of styrene sulfonate and maleic anhydride.

  11. System and method for controlling hydrogen elimination during carbon nanotube synthesis from hydrocarbons

    DOEpatents

    Reilly, Peter T. A.

    2010-03-23

    A system and method for producing carbon nanotubes by chemical vapor deposition includes a catalyst support having first and second surfaces. The catalyst support is capable of hydrogen transport from the first to the second surface. A catalyst is provided on the first surface of the catalyst support. The catalyst is selected to catalyze the chemical vapor deposition formation of carbon nanotubes. A fuel source is provided for supplying fuel to the catalyst.

  12. A cost effective, sensitive, and environmentally friendly sample preparation method for determination of Polycyclic Aromatic Hydrocarbons in solid samples

    PubMed Central

    Yamaguchi, Chika; Lee, Wen-Yee

    2010-01-01

    A simple, cost effective, and yet sensitive sample preparation technique was investigated for determining polycyclic aromatic hydrocarbons (PAHs) in solid samples. The method comprises ultrasonic extraction, Stir Bar Sorptive Extraction (SBSE), and thermal desorption-gas chromatography-mass spectrometry (TD – GC/MS) to increase analytical capacity in laboratories. This method required no clean-up and satisfied PAHs recovery and significantly advances cost performance over conventional extraction methods, such as Soxhlet and Microwave Assisted Extraction (MAE). This study evaluated three operational parameters for ultrasonic extraction: solvent composition, extraction time, and sample load. A standard material, SRM 1649 a (urban dust), was used as the solid sample matrix, and 12 priority PAHs on the US Environmental Protection Agency (US EPA) list were analyzed. Combination of non-polar and polar solvents ameliorated extraction efficiency. Acetone/hexane mixtures of 2:3 and 1:1 (v/v) gave the most satisfactory results: recoveries ranged from 63.3 % to 122 %. Single composition solvents (methanol, hexane, and dichloromethane) showed fewer recoveries. Comparing 20 minutes with 60 minutes sonication, longer sonication diminished extraction efficiencies in general. Furthermore, sample load became a critical factor in certain solvent systems, such as MeOH. MAE was also compared to the ultrasonic extraction, and results determined that the 20-minutes ultrasonic extraction using acetone / hexane (2:3 v/v) was as potent as MAE. The SBSE method using 20 mL of 30 % alcohol-fortified solution rendered a limit of detection ranging from 1.7 to 32 ng L−1 and a limit of quantitation ranging from 5.8 to 110 ng L−1 for the 16 US EPA PAHs. PMID:20851399

  13. Application of InSAR and gravimetric surveys for developing construction codes in zones of land subsidence induced by groundwater extraction: case study of Aguascalientes, Mexico

    NASA Astrophysics Data System (ADS)

    Pacheco-Martínez, J.; Wdowinski, S.; Cabral-Cano, E.; Hernández-Marín, M.; Ortiz-Lozano, J. A.; Oliver-Cabrera, T.; Solano-Rojas, D.; Havazli, E.

    2015-11-01

    Interferometric Synthetic Aperture Radar (InSAR) has become a valuable tool for surface deformation monitoring, including land subsidence associated with groundwater extraction. Another useful tools for studying Earth's surface processes are geophysical methods such as Gravimetry. In this work we present the application of InSAR analysis and gravimetric surveying to generate valuable information for risk management related to land subsidence and surface faulting. Subsidence of the city of Aguascalientes, Mexico is presented as study case. Aguascalientes local governments have addressed land subsidence issues by including new requirements for new constructions projects in the State Urban Construction Code. Nevertheless, the resulting zoning proposed in the code is still subjective and not clearly defined. Our work based on gravimetric and InSAR surveys is aimed for improving the subsidence hazard zoning proposed in the State Urban Code in a more comprehensive way. The study includes a 2007-2011 ALOS InSAR time-series analysis of the Aguascalientes valley, an interpretation of the compete Bouguer gravimetric anomaly of the Aguascalientes urban area, and the application of time series and gravimetric anomaly maps for improve the subsidence hazard zoning of Aguascalientes City.

  14. Machine method for determining the presence and location of hydrocarbon deposits within a subsurface earth formation

    SciTech Connect

    Clavier, Ch. M.; Dumanoir, J. L.; Dumestre, A. C.

    1985-02-26

    In accordance with illustrative embodiments of the present invention, methods for processing well logging data comprises deriving measurements of a plurality of earth formations parameters and combining these measurements in a new manner to enable interpretation of shales and shaly sand type formations. More particularly, measurements of a plurality of the hydrogen index, bulk density, radially deep and shallow resistivity, spontaneous potential, acoustic travel time and natural formation radioactivity content are made and combined in a manner to produce data useful in evaluating shales and shaly sand type formations.

  15. Method of viscosifying aqueous fluids and process for recovery of hydrocarbons from subterranean formations

    SciTech Connect

    Borchardt, J. K.

    1985-06-18

    The present invention relates to a method of viscosifying aqueous fluids and a viscosifying composition which when admixed with an aqueous fluid produces a viscosity increase in the fluid in excess of the additive viscosity of the individual composition components. The viscosifying composition comprises at least one member selected from the group consisting of sulfonated guar and a compound comprising at least one member selected from the group consisting of xanthan gum, guar, hydroxypropyl guar, hydroxypropyl guar derivatives, hydroxyethyl cellulose and hydroxyethyl cellulose derivatives and cationic guar and a compound comprising at least one member selected from the group consisting of hydroxypropyl guar, hydroxypropyl guar derivatives, hydroxyethyl cellulose and hydroxyethyl cellulose derivatives.

  16. Evaluation of field methods for estimating exposure of children in low-income families to polycyclic aromatic hydrocarbons

    SciTech Connect

    Wilson, N.K.; Chuang, J.C.; Lyu, C.

    1996-12-31

    Children in low-income families may have higher exposures to polycyclic aromatic hydrocarbons (PAH) and related compounds than children in higher-income families. These higher exposures could result from the location of their homes, nearer to industrial sites and traffic; from poorer diet; from environmental tobacco smoke; or other causes. The study was designed to evaluate methods and estimate the range of total exposures of low-income children to PAH through various pathways. Nonsmoking participants with preschool children, incomes at or below the official US poverty level, and space heating in their homes were recruited. The PAH concentrations were measured in the household indoor and outdoor air, house dust, and yard soil, and in the diet of both an adult and a preschool child living in the home. An initial study in two homes and an additional study of nine homes, four urban and five rural, during the heating season were completed. The problems and successes encountered in the recruitment process and selected results of the heating season measurements are summarized in the paper.

  17. Evaluation of Chemical Analysis Method and Determination of Polycyclic Aromatic Hydrocarbons Content from Seafood and Dairy Products

    PubMed Central

    Lee, So-Young; Lee, Jee-Yeon

    2015-01-01

    This study was carried out to investigate contents of 8 polycyclic aromatic hydrocarbons (PAHs) from frequently consumed seafood and dairy products and to evaluate their chemical analysis methods. Samples were collected from markets of 9 cities in Korea chosen as the population reference and evaluated. The methodology involved saponification, extraction with n-hexane, clean-up on Sep-Pak silica cartridges and gas chromatograph-mass spectrometry analysis. Validation proceeded on 2 matrices. Recoveries for 8 PAHs ranged from 86.87 to 103.57%. The limit of detection (LOD) 8 PAHs was 0.04~0.20 µg/kg, and limit of quantification (LOQ) of 8 PAHs was 0.12~0.60 µg/kg. The mean concentration of benzo[a]pyrene (BaP) was 0.34 µg/kg from seafood and 0.34 µg/kg from dairy products. The total PAHs concentration was 1.06 µg/kg in seafood and 1.52 µg/kg in dairy products. PMID:26483885

  18. Studies on the dissolution of polycyclic aromatic hydrocarbons from contaminated materials using a novel dialysis tubing experimental method

    SciTech Connect

    Woolgar, P.J. Scottish Environment Protection Agency, Stirling ); Jones, K.C. )

    1999-06-15

    Assessment of risk and remediation strategies at contaminated sites requires that both the amounts of contaminants present and their potential for release from materials and soils be evaluated. The release, or dissolution, of polycyclic aromatic hydrocarbons (PAHs) from contaminated materials to water was therefore investigated. To facilitate investigations of PAH dissolution from physically disparate materials such as solid coal tars, creosote, oil, and spent oxide, an experimental method for measuring dissolved PAHs was developed employing dialysis tubing in batch-type system. This was validated and compared to aqueous-phase PAH concentrations measured using more traditional techniques and also predicted using Raoult's law. The experimental procedure was successfully used to determine near equilibrium aqueous concentrations of PAHs, but it could only be used to determine relative rates of approach to equilibrium as the dialysis tubing effected the rate constants. It was found that the contaminant materials influenced dissolution, in particular the close to equilibrium concentrations. For materials chemically similar to PAHs, such as nonaqueous-phase liquids (NAPLs), the concentrations could be predicted using Raoult's law. For materials that were chemically dissimilar to PAHs, such as spent oxide, release was more thermodynamically favorable than for NAPLs.

  19. Identifying sources of chlorinated aliphatic hydrocarbons in a residential area in Italy using the integral pumping test method

    NASA Astrophysics Data System (ADS)

    Alberti, Luca; Lombi, Silvia; Zanini, Andrea

    2011-09-01

    The results of integral pumping tests (IPTs) performed in the city of Fabriano, Italy, are presented. The IPT methodology was developed by the European Union project INCORE, as a tool for groundwater investigation and source localization in contaminated areas. This methodology consists of a multiple-well pumping test in which the wells are positioned along a control plane downstream of suspected contaminant source zones and perpendicular to the mean groundwater flow direction. During the pumping, concentration time series of target contaminants are measured. In Fabriano, two control planes were realized to identify a chlorinated aliphatic hydrocarbon plume, to estimate the mass fluxes and draw up a ranked list of the main contamination sources. A numerical flow model was implemented to support the IPT design and to interpret the results. This study revealed low-level trichloroethylene contamination (concentration below 8 μg/l), tetrachloroethylene contamination (mean concentration up to 500 μg/l) and a mass flow rate of about 300 g/day. Through the application of the IPT method, the mean contaminant concentrations, the spatial distribution of concentration values along the control planes, and the total contaminant mass flow rates were evaluated, and the investigation area was reduced for further and deeper investigation activities.

  20. The potential of solvent-minimized extraction methods in the determination of polycyclic aromatic hydrocarbons in fish oils.

    PubMed

    Yebra-Pimentel, Iria; Martínez-Carballo, Elena; Regueiro, Jorge; Simal-Gándara, Jesús

    2013-08-15

    Fish oil has been identified as one of the most important contributors to the level of Persistent Organic Pollutants (POPs) in feed products. The determination of polycyclic aromatic hydrocarbons (PAHs) in fish oils is complicated due to the fat matrix, which affects both extraction efficiency and analytical quality. This article reviews and addresses two of the most relevant analytical methods for determining 11 mutagenic and carcinogenic PAHs, as well as two EPA indicator PAHs in fish oils. We discuss and critically evaluate two different extraction procedures, such as ultrasound-assisted solvent extraction (USAE) and ultrasound-assisted emulsification-microextraction (USAEME). Clean-up of extracts was performed by solid-phase extraction using C18 and glass columns containing silica gel and florisil for USAE or only C18 for USAEME. Detection of the selected PAHs was carried out by high-performance liquid chromatography coupled with fluorescence detection for determination. Optimization of the variables affecting extraction by the selected extraction techniques was conducted and recoveries ranged from 70% to 100% by USAE and from 70% to 108% by USAEME with estimated quantification limits between 0.020 and 2.6 μg/kg were achieved. Moreover, the applicability of the selected methods was evaluated by the analysis of real samples. To our knowledge, this is the first time that USAEME has been applied to the determination of PAHs in food matrices, such as oil fish samples. The methods proposed were applied to the determination of the target PAHs in fish samples from different countries, and it was found that the low PAH contamination of the selected fish oils could mainly occur by atmospheric sources. PMID:23561207

  1. Method for recovery of hydrocarbons form contaminated soil or refuse materials

    DOEpatents

    Ignasiak, Teresa; Turak, Ali A.; Pawlak, Wanda; Ignasiak, Boleslaw L.; Guerra, Carlos R.; Zwillenberg, Melvin L.

    1991-01-01

    A method is provided for separating an inert solid substantially inorganic fraction comprising sand or soil from a tarry or oily organic matter in a feedstock. The feedstock may be contaminated soil or tarry waste. The feedstock is combined with pulverized coal and water. The ratio (oil or tar to dry weight of coal) of about 1.0:10 to about 4.0:10 at a temperature in the range of 60.degree.-95.degree. C. The mixture is agitated, the coarse particles are removed, and up to about 0.10% by weight (based on weight of coal) of a frothing agent is added. The mixture is then subjected to flotation, and the froth is removed from the mixture.

  2. Decontamination of produced water containing petroleum hydrocarbons by electrochemical methods: a minireview.

    PubMed

    dos Santos, Elisama Vieira; Bezerra Rocha, Jessica Horacina; de Araújo, Danyelle Medeiros; de Moura, Dayanne Chianca; Martínez-Huitle, Carlos Alberto

    2014-01-01

    Produced water (PW) is the largest waste stream generated in oil and gas industries. The drilling and extraction operations that are aimed to maximize the production of oil may be counterbalanced by the huge production of contaminated water (called PW) with pollutants, such as heavy metals, dissolved/suspended solids, and organic compounds. PW is conventionally treated through different physical, chemical, and biological methods. In offshore platforms, because of space constraints, compact physical and chemical systems are used. However, major research efforts are being developed with innovative technologies for treating PW in order to comply with reuse and discharge limits. Among them, electrochemical technologies have been proposed as a promising alternative for the treatment of this kind of wastewaters. Then, this paper presents a minireview of efficient electrochemical technologies used until now for treating PW generated by petrochemical industry. PMID:24671399

  3. A Study on Gravimetric Geoid Determination Using Analytical Downward Continuation Technique

    NASA Astrophysics Data System (ADS)

    Sezen, Erdinç; Doǧan, Uǧur; Yıldız, Hasan

    2016-04-01

    The Stokes' formula requires the gravity anomaly on the Earth's surface be downward continued to the geoid and the mass above the geoid be removed. Although the Earth Gravity Field Models (EGMs) are used to compute quasi geoid models, gravimetric geoid determination is possible taking into account the topographic effects. Analytical or harmonic downward continuation of external gravity potential of the Earth into the topographic masses results in "analytical downward continuation error" or "topographic bias". One of the alternatives to compute topographic bias is spherical harmonic expansion of reciprocal distance including functional coefficients of Earth's radius and topographic height depending on the position. Spherical harmonic coefficients are then expanded into binomial series to compute the difference between the topographical potential and its downward continuation. On any coordinates on the Earth, topographic bias can easily be computed using these coefficients. Topographic bias provides a practical way to compute a regional geoid model transforming height anomalies computed from EGMs to geoid undulations. Using this technique, regional geoid models are determined in two test areas, the Auvergne, France and New Mexico, U.S.A, and compared with the GNSS/levelling geoid undulations and the regional geoid models computed using Least Squares Modification of Stokes' Formula (KTH method). Keywords: Analytical downward continuation, topographic bias, geoid determination, Earth Gravity Model, Least Squares Modification of Stokes' Formula (KTH method).

  4. First Release of Gravimetric Geoid Model over Saudi Arabia Based on Terrestrial Gravity and GOCE Satellite Data: KSAG01

    NASA Astrophysics Data System (ADS)

    Alothman, Abdulaziz; Elsaka, Basem

    2016-04-01

    A new gravimetric quasi-geoid, known as KSAG0, has been developed recently by Remove-Compute-Restore techniques (RCR), provided by the GRAVSOFT software, using gravimetric free air anomalies. The terrestrial gravity data used in this computations are: 1145 gravity field anomalies observed by ARAMCO (Saudi Arabian Oil Company) and 2470 Gravity measurements from BGI (Bureau Gravimétrique International). The computations were carried out implementing the least squares collocation method through the RCR techniques. The KSAG01 is based on merging in addition to the terrestrial gravity observations, GOCE satellite model (Eigen-6C4) and global gravity model (EGM2008) have been utilized in the computations. The long, medium and short wavelength spectrum of the height anomalies were compensated from Eigen-6C4 and EGM2008 geoid models truncated up to Degree and order (d/o) up to 2190. KSAG01 geoid covers 100 per cent of the kingdom, with geoid heights range from - 37.513 m in the southeast to 23.183 m in the northwest of the country. The accuracy of the geoid is governed by the accuracy, distribution, and spacing of the observations. The standard deviation of the predicted geoid heights is 0.115 m, with maximum errors of about 0.612 m. The RMS of geoid noise ranges from 0.019 m to 0.04 m. Comparison of the predicted gravimetric geoid with EGM, GOCE, and GPS/Levelling geoids, reveals a considerable improvements of the quasi-geoid heights over Saudi Arabia.

  5. Physically constrained source apportionment (PCSA) for polycyclic aromatic hydrocarbon using the Multilinear Engine 2-species ratios (ME2-SR) method.

    PubMed

    Liu, Gui-Rong; Shi, Guo-Liang; Tian, Ying-Ze; Wang, Yi-Nan; Zhang, Cai-Yan; Feng, Yin-Chang

    2015-01-01

    An improved physically constrained source apportionment (PCSA) technology using the Multilinear Engine 2-species ratios (ME2-SR) method was proposed and applied to quantify the sources of PM10- and PM2.5-associated polycyclic aromatic hydrocarbons (PAHs) from Chengdu in winter time. Sixteen priority PAH compounds were detected with mean ΣPAH concentrations (sum of 16 PAHs) ranging from 70.65 ng/m(3) to 209.58 ng/m(3) and from 59.17 ng/m(3) to 170.64 ng/m(3) for the PM10 and PM2.5 samples, respectively. The ME2-SR and positive matrix factorization (PMF) models were employed to estimate the source contributions of PAHs, and these estimates agreed with the experimental results. For the PMF model, the highest contributor to the ΣPAHs was vehicular emission (81.69% for PM10, 82.06% for PM2.5), followed by coal combustion (12.68%, 12.11%), wood combustion (5.65%, 4.45%) and oil combustion (0.72%, 0.88%). For the ME2-SR method, the highest contributions were from diesel (43.19% for PM10, 47.17% for PM2.5) and gasoline exhaust (34.94%, 32.44%), followed by wood combustion (8.79%, 6.37%), coal combustion (12.46%, 12.37%) and oil combustion (0.80%, 1.22%). However, the PAH ratios calculated for the factors extracted by ME2-SR were closer to the values from actual source profiles, implying that the results obtained from ME2-SR might be physically constrained and satisfactory. PMID:25240101

  6. THE PHOTOTOXICITY OF POLYCYCLIC AROMATIC HYDROCARBONS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) continues to be interested in developing methods for the detection of polycyclic aromatic hydrocarbons (PAHS) in the environment. Polycyclic aromatic hydrocarbons (PAHS) are common contaminants in our environment. Being major product...

  7. QuEChERS Method Followed by Solid Phase Extraction Method for Gas Chromatographic-Mass Spectrometric Determination of Polycyclic Aromatic Hydrocarbons in Fish.

    PubMed

    Khorshid, Mona; Souaya, Eglal R; Hamzawy, Ahmed H; Mohammed, Moustapha N

    2015-01-01

    A gas chromatography equipped with mass spectrometer (GCMS) method was developed and validated for determination of 16 polycyclic aromatic hydrocarbons (PAHs) in fish using modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for extraction and solid phase extraction for sample cleanup to remove most of the coextract combined with GCMS for determination of low concentration of selected group of PAHs in homogenized fish samples. PAHs were separated on a GCMS with HP-5ms Ultra Inert GC Column (30 m, 0.25 mm, and 0.25 µm). Mean recovery ranged from 56 to 115%. The extraction efficiency was consistent over the entire range where indeno(1,2,3-cd)pyrene and benzo(g,h,i)perylene showed recovery (65, 69%), respectively, at 2 µg/kg. No significant dispersion of results was observed for the other remaining PAHs and recovery did not differ substantially, and at the lowest and the highest concentrations mean recovery and RSD% showed that most of PAHs were between 70% and 120% with RSD less than 10%. The measurement uncertainty is expressed as expanded uncertainty and in terms of relative standard deviation (at 95% confidence level) is ±12%. This method is suitable for laboratories engaged daily in routine analysis of a large number of samples. PMID:25873966

  8. QuEChERS Method Followed by Solid Phase Extraction Method for Gas Chromatographic-Mass Spectrometric Determination of Polycyclic Aromatic Hydrocarbons in Fish

    PubMed Central

    Khorshid, Mona; Souaya, Eglal R.; Hamzawy, Ahmed H.; Mohammed, Moustapha N.

    2015-01-01

    A gas chromatography equipped with mass spectrometer (GCMS) method was developed and validated for determination of 16 polycyclic aromatic hydrocarbons (PAHs) in fish using modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for extraction and solid phase extraction for sample cleanup to remove most of the coextract combined with GCMS for determination of low concentration of selected group of PAHs in homogenized fish samples. PAHs were separated on a GCMS with HP-5ms Ultra Inert GC Column (30 m, 0.25 mm, and 0.25 µm). Mean recovery ranged from 56 to 115%. The extraction efficiency was consistent over the entire range where indeno(1,2,3-cd)pyrene and benzo(g,h,i)perylene showed recovery (65, 69%), respectively, at 2 µg/kg. No significant dispersion of results was observed for the other remaining PAHs and recovery did not differ substantially, and at the lowest and the highest concentrations mean recovery and RSD% showed that most of PAHs were between 70% and 120% with RSD less than 10%. The measurement uncertainty is expressed as expanded uncertainty and in terms of relative standard deviation (at 95% confidence level) is ±12%. This method is suitable for laboratories engaged daily in routine analysis of a large number of samples. PMID:25873966

  9. Method of using an aqueous chemical system to recover hydrocarbon and minimize wastes from sludge deposits in oil storage tanks

    SciTech Connect

    Goss, M.L.

    1992-02-04

    This patent describes a process for separating and removing a hydrocarbon, water and solid components of sludge deposited in an oil storage tank. It comprises: introducing a sufficient amount of a nonionic surfactant in an aqueous solution to form a layer of the solution above the sludge layer; the nonionic surfactant comprising: C{sub 8}-C{sub 12} alkylphenol-ethylene oxide adducts of about 55%-75% by weight ethylene oxide, and at least one castor oil-ethylene oxide adduct of about 55%-75% by weight ethylene oxide; the nonionic surfactant being present in a quantity sufficient to separate hydrocarbon component from the sludge without forming an emulsion, adding a diluent, immiscible with the aqueous layer, for extracting the hydrocarbons, and separately draining the diluent layer and aqueous layer from the tank.

  10. Advanced Nanoporous Materials for Micro-Gravimetric Sensing to Trace-Level Bio/Chemical Molecules

    PubMed Central

    Xu, Pengcheng; Li, Xinxin; Yu, Haitao; Xu, Tiegang

    2014-01-01

    Functionalized nanoporous materials have been developed recently as bio/chemical sensing materials. Due to the huge specific surface of the nano-materials for molecular adsorption, high hopes have been placed on gravimetric detection with micro/nano resonant cantilevers for ultra-sensitive sensing of low-concentration bio/chemical substances. In order to enhance selectivity of the gravimetric resonant sensors to the target molecules, it is crucial to modify specific groups onto the pore-surface of the nano-materials. By loading the nanoporous sensing material onto the desired region of the mass-type transducers like resonant cantilevers, the micro-gravimetric bio/chemical sensors can be formed. Recently, such micro-gravimetric bio/chemical sensors have been successfully applied for rapid or on-the-spot detection of various bio/chemical molecules at the trace-concentration level. The applicable nanoporous sensing materials include mesoporous silica, zeolite, nanoporous graphene oxide (GO) and so on. This review article focuses on the recent achievements in design, preparation, functionalization and characterization of advanced nanoporous sensing materials for micro-gravimetric bio/chemical sensing. PMID:25313499

  11. THE APPLICATION OF COMPUTATIONAL MOLECULAR METHODS TO UNDERSTAND THE HEALTH EFFECTS OF ENVIRONMENTAL CHEMICALS-POLYCYCLIC AROMATIC HYDROCARBONS

    EPA Science Inventory

    In evaluating the risk posed by chemicals introduced into the environment, information
    about their molecular mechanism of action provides a basis for extrapolating from the
    laboratory to the environment. Polycyclic aromatic hydrocarbons (PAH) are a large class
    of...

  12. Gravity effects obtained from global hydrology models in comparison with high precision gravimetric time series

    NASA Astrophysics Data System (ADS)

    Wziontek, Hartmut; Wilmes, Herbert; Güntner, Andreas; Creutzfeldt, Benjamin

    2010-05-01

    Water mass changes are a major source of variations in residual gravimetric time series obtained from the combination of observations with superconducting and absolute gravimeters. Changes in the local water storage are the main influence, but global variations contribute to the signal significantly. For three European gravity stations, Bad Homburg, Wettzell and Medicina, different global hydrology models are compared. The influence of topographic effects is discussed and due to the long-term stability of the combined gravity time series, inter-annual signals in model data and gravimetric observations are compared. Two sources of influence are discriminated, i.e., the effect of a local zone with an extent of a few kilometers around the gravimetric station and the global contribution beyond 50km. Considering their coarse resolution and uncertainties, local effects calculated from global hydrological models are compared with the in-situ gravity observations and, for the station Wettzell, with local hydrological monitoring data.

  13. QUANTIFICATION AND INTERPRETATION OF TOTAL PETROLEUM HYDROCARBONS IN SEDIMENT SAMPLES BY A GC/MS METHOD AND COMPARISON WITH EPA 418.1 AND A RAPID FIELD METHOD

    EPA Science Inventory

    ABSTRACT: Total Petroleum hydrocarbons (TPH) as a lumped parameter can be easily and rapidly measured or monitored. Despite interpretational problems, it has become an accepted regulatory benchmark used widely to evaluate the extent of petroleum product contamination. Three cu...

  14. Polynuclear aromatic hydrocarbons for fullerene synthesis in flames

    DOEpatents

    Alford, J. Michael; Diener, Michael D.

    2006-12-19

    This invention provides improved methods for combustion synthesis of carbon nanomaterials, including fullerenes, employing multiple-ring aromatic hydrocarbon fuels selected for high carbon conversion to extractable fullerenes. The multiple-ring aromatic hydrocarbon fuels include those that contain polynuclear aromatic hydrocarbons. More specifically, multiple-ring aromatic hydrocarbon fuels contain a substantial amount of indene, methylnapthalenes or mixtures thereof. Coal tar and petroleum distillate fractions provide low cost hydrocarbon fuels containing polynuclear aromatic hydrocarbons, including without limitation, indene, methylnapthalenes or mixtures thereof.

  15. Density variations between the southern and northern hemisphere of Mars: Implications from gravimetric inversion

    NASA Astrophysics Data System (ADS)

    Breuer, D.; Pauer, M.

    2008-12-01

    One remarkable feature of Mars is the crustal dichotomy which divides the surface into an old southern highland hemisphere rising several kilometers above the zero level and a superficially younger northern lowlands hemisphere well below the datum. Whether this crustal dichotomy is also reflected in composition, density, and thickness is not known -- although, a crustal thickness variation is generally suggested based on the assumption of a constant crustal density. We used gravimetric methods to place constraints on the maximum crustal density of the southern highlands. Gravimetric methods are ambiguous with a noted trade- off between the crustal thickness and density. However, combining two different methods, the geoid- topography ratio and Bouguer inversion, helps to constrain a maximum density of the crust for regions that show a homogeneous unit with respect to lateral density variations and compensation state. For the Martian Noachian southern highlands a combination of these methods suggests a maximum crustal density of 3020 ± 70 kgm-3, assuming a single-layer crustal structure. Two-layer crustal structures show similar results: the upper crustal density is also limited to ~ 3000 kgm-3, but a denser uniformly thick lower crust is possible. The obtained results together with the findings on crustal densities (and composition) of other regions on Mars are consistent with various scenarios of crustal evolution: 1) A 'temporal' evolution in the densities with low densities of the ancient crust and comparatively higher densities of the young (Amazonian-era) volcanic material. Such a 'temporal' increase may result from different formation mechanisms or possibly from a change in composition of the basaltic magmas over time. 2) The density variation is already manifested in the early evolution during the formation of the crustal dichotomy, i.e. the Noachian crust of the northern lowlands has a different density than the Noachian southern highland crust. The ancient

  16. A rapid method for the measurement and estimation of CO2 diffusivity in liquid hydrocarbon-saturated porous media using MRI.

    PubMed

    Zhao, Yuechao; Chen, Junlin; Yang, Mingjun; Liu, Yu; Song, Yongchen

    2016-05-01

    In this study, magnetic resonance imaging (MRI) was used to dynamically visualize the diffusion process of CO2 in porous media saturated with liquid hydrocarbon. Based on the assumption of semi-infinite media, effective CO2 diffusivity was obtained directly by the nonlinear fitting of one MR profile during the diffusion process. These experimental findings obtained based on MRI method showed a close agreement with the conventional pressure-volume-temperature method. The novel MRI-based technique is a time-saving approach that can reduce the duration of CO2 diffusivity measurement more than 90%, and realize rapid and accurate measurement and estimation of CO2 diffusivity. PMID:26707850

  17. Process for recovering hydrocarbons from a hydrocarbon-bearing formation

    SciTech Connect

    Alston, R.B.; Braden, W.B.; Flournoy, K.H.

    1980-03-11

    A method is described for transporting heavy crude oil through a pipeline which involves introducing into a pipeline or well-bore with the viscous hydrocarbons an aqueous solution containing (1) a sulfonate surfactant, (2) a rosin soap or a naphthenic acid soap and, optionally (3) coupling agent whereby there is spontaneously formed a low viscosity, salt tolerant, oil-in-water emulsion. Also disclosed is a method of recovery of hydrocarbons from a hydrocarbon bearing formation employing an aqueous solution containing (1) a sulfonate surfactant, (2) a rosin soap or a naphthenic acid soap and, optionally (3) a coupling agent.

  18. Gravimetric excitation function of polar motion from the GRACE RL05 solution

    NASA Astrophysics Data System (ADS)

    Nastula, Y.

    2014-12-01

    Impact of land hydrosphere on polar motion excitation is still not as well known as the impact of the angular momentum of the atmosphere and ocean. Satellite mission Gravity Recovery and Climate Experiment (GRACE) from 2002 provides additional information about mass distribution of the land hydrosphere. However, despite the use of similar computational procedures, the differences between GRACE data series made available by the various centers of computations are still considerable. In the paper we compare three series of gravimetric excitation functions of polar motion determined from Rl05 GRACE solution from the Center for Space Research (CSR), the Jet Propulsion Laboratory (JPL) and the GeoForschungsZentrum (GFZ). These data are used to determine the gravimetric polar motion excitation function. Gravimetric signal is compared also with the geodetic residuals computed by subtracting atmospheric and oceanic signals from geodetic excitation functions of polar motion. Gravimetric excitation functions obtained on the basis of JPL data differ significantly from the geodetic residuals while and the series obtained from CSR and GFZ are more compatible.

  19. Comparing Gravimetric and Real-Time Sampling of PM2.5 Concentrations Inside Truck Cabins

    PubMed Central

    Zhu, Ying; Smith, Thomas J.; Davis, Mary E.; Levy, Jonathan I.; Herrick, Robert; Jiang, Hongyu

    2012-01-01

    As part of a study on truck drivers’ exposure and health risk, pickup and delivery (P&D) truck drivers’ on-road exposure patterns to PM2.5 were assessed in five weeklong sampling trips in metropolitan areas of five U.S. cities from April to August of 2006. Drivers were sampled with real-time (DustTrak) and gravimetric samplers to measure average in-cabin PM2.5 concentrations and to compare their correspondence in moving trucks. In addition, GPS measurements of truck locations, meteorological data, and driver behavioral data were collected throughout the day to determine which factors influence the relationship between real-time and gravimetric samplers. Results indicate that the association between average real-time and gravimetric PM2.5 measurements on moving trucks was fairly consistent (Spearman rank correlation of 0.63), with DustTrak measurements exceeding gravimetric measurements by approximately a factor of 2. This ratio differed significantly only between the industrial Midwest cities and the other three sampled cities scattered in the South and West. There was also limited evidence of an effect of truck age. Filter samples collected concurrently with DustTrak measurements can be used to calibrate average mass concentration responses for the DustTrak, allowing for real-time measurements to be integrated into longer-term studies of inter-city and intra-urban exposure patterns for truck drivers. PMID:21991940

  20. Gravimetric Analysis of Bismuth in Bismuth Subsalicylate Tablets: A Versatile Quantitative Experiment for Undergraduate Laboratories

    ERIC Educational Resources Information Center

    Davis, Eric; Cheung, Ken; Pauls, Steve; Dick, Jonathan; Roth, Elijah; Zalewski, Nicole; Veldhuizen, Christopher; Coeler, Joel

    2015-01-01

    In this laboratory experiment, lower- and upper-division students dissolved bismuth subsalicylate tablets in acid and precipitated the resultant Bi[superscript 3+] in solution with sodium phosphate for a gravimetric determination of bismuth subsalicylate in the tablets. With a labeled concentration of 262 mg/tablet, the combined data from three…

  1. On-chip temperature-compensated Love mode surface acoustic wave device for gravimetric sensing

    NASA Astrophysics Data System (ADS)

    Liu, Q.; Flewitt, A. J.

    2014-11-01

    Love mode surface acoustic wave (SAW) sensors have been recognized as one of the most sensitive devices for gravimetric sensors in liquid environments such as bio sensors. Device operation is based upon measuring changes in the transmitted (S21) frequency and phase of the first-order Love wave resonance associated with the device upon on attachment of mass. However, temperature variations also cause a change in the first order S21 parameters. In this work, shallow grooved reflectors and a "dotted" single phase unidirectional interdigitated transducer (D-SPUDT) have been added to the basic SAW structure, which promote unidirectional Love wave propagation from the device's input interdigitated transducers. Not only does this enhance the first-order S21 signal but also it allows propagation of a third-order Love wave. The attenuation coefficient of the third-order wave is sufficiently great that, whilst there is a clear reflected S11 signal, the third-order wave does not propagate into the gravimetric sensing area of the device. As a result, whilst the third-order S11 signal is affected by temperature changes, it is unaffected by mass attachment in the sensing area. It is shown that this signal can be used to remove temperature effects from the first-order S21 signal in real time. This allows gravimetric sensing to take place in an environment without the need for any other temperature measurement or temperature control; this is a particular requirement of gravimetric biosensors.

  2. Comparing gravimetric and real-time sampling of PM(2.5) concentrations inside truck cabins.

    PubMed

    Zhu, Ying; Smith, Thomas J; Davis, Mary E; Levy, Jonathan I; Herrick, Robert; Jiang, Hongyu

    2011-11-01

    As part of a study on truck drivers' exposure and health risk, pickup and delivery (P&D) truck drivers' on-road exposure patterns to PM(2.5) were assessed in five, weeklong sampling trips in metropolitan areas of five U.S. cities from April to August of 2006. Drivers were sampled with real-time (DustTrak) and gravimetric samplers to measure average in-cabin PM(2.5) concentrations and to compare their correspondence in moving trucks. In addition, GPS measurements of truck locations, meteorological data, and driver behavioral data were collected throughout the day to determine which factors influence the relationship between real-time and gravimetric samplers. Results indicate that the association between average real-time and gravimetric PM(2.5) measurements on moving trucks was fairly consistent (Spearman rank correlation of 0.63), with DustTrak measurements exceeding gravimetric measurements by approximately a factor of 2. This ratio differed significantly only between the industrial Midwest cities and the other three sampled cities scattered in the South and West. There was also limited evidence of an effect of truck age. Filter samples collected concurrently with DustTrak measurements can be used to calibrate average mass concentration responses for the DustTrak, allowing for real-time measurements to be integrated into longer-term studies of inter-city and intra-urban exposure patterns for truck drivers. PMID:21991940

  3. Geopotential coefficient determination and the gravimetric boundary value problem: A new approach

    NASA Technical Reports Server (NTRS)

    Sjoeberg, Lars E.

    1989-01-01

    New integral formulas to determine geopotential coefficients from terrestrial gravity and satellite altimetry data are given. The formulas are based on the integration of data over the non-spherical surface of the Earth. The effect of the topography to low degrees and orders of coefficients is estimated numerically. Formulas for the solution of the gravimetric boundary value problem are derived.

  4. Gravimetric Determination of Inorganic Carbon in Calcareous Soils Using the Carbonate-Meter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic carbon affects many important physical, chemical and microbiological soil properties. In calcareous soils, the inorganic carbon has to be measured and subtracted from the total carbon to obtain organic carbon. Our objective was to develop a gravimetric technique to quantify inorganic carbon ...

  5. Modelling Gravimetric Fluctuations due to Hydrological Processes in Active Volcanic Settings

    NASA Astrophysics Data System (ADS)

    Hemmings, B.; Gottsmann, J.; Whitaker, F.

    2014-12-01

    Both static and dynamic gravimetric surveys are widely used to monitor magmatic processes in active volcanic settings. However, attributing residual gravimetric signals solely to magma movement can result in misdiagnosis of a volcano's pre-eruptive state and incorrect assessment of hazard. The relative contribution of magmatic and aqueous fluids to integrated gravimetric and geodetic data has become an important topic for debate, particularly in restless caldera systems. Groundwater migration driven by volcanically-induced pressure changes, and groundwater mass fluctuations associated with seasonal and inter-annual variations in recharge may also contribute to measured gravity changes. Here we use numerical models to explore potential gravimetric signals associated with fundamental hydrological processes, focusing on variations in recharge and hydrogeological properties. TOUGH2 simulations demonstrate the significance of groundwater storage within a thick unsaturated zone (up to 100 m). Changes are dominantly in response to inter-annual recharge variations and can produce measurable absolute gravity variations of several 10s of μgal. Vadose zone storage and the rate of response to recharge changes depend on the hydrological properties. Porosity, relative and absolute permeability and capillary pressure conditions all affect the amplitude and frequency of modelled gravity time series. Spatial variations in hydrologic properties and importantly, hydrological recharge, can significantly affect the phase and amplitude of recorded gravity signals. Our models demonstrate the potential for an appreciable hydrological component within gravimetric measurements on volcanic islands. Characterisation of hydrological processes within a survey area may be necessary to robustly interpret gravity signals in settings with significant recharge fluctuations, a thick vadose zone and spatially variable hydrological properties. Such modelling enables further exploration of feedbacks

  6. Gravimetric measurements of materials outgassing applied to graphite-epoxy laminates

    NASA Technical Reports Server (NTRS)

    Scialdone, John J.

    1989-01-01

    The outgassing rates of two graphite-epoxy laminates, American Cyanamide 985B-626 and HST-7B-112, were obtained using a gravimetric method. The rates as a function of time and temperature were derived from the measurements of their mass losses at temperatures varying from 25 to 150 C and for a time span of up to 400 hours in a vacuum. The data from those measurements were reduced to obtain the outgassing activation energies, the mass losses per unit mass or area, and the corresponding outgassing rates. The rates are expressed in closed-form equations and are directly usable for medling computations. The procedures to obtain these parameters are shown and may be used for the evaluation of other materials. The results of the tests show that the activation energies of the two materials are: 4630 cal/mole for the 985B-626 materials and 4791 cal/mole for the HST-7B-112 sample no. 10 Graphite Exoxy. The outgassing rates of these materials are in the 10E-5 g/sq cm/hr range and they decay according to a power of time of 0.60 at 25 C, indicating that the outgassing process is mainly a diffusion at that temperature. The normalized mass losses versus time obtained from these tests were compared to the discrete results obtained from the ASTM-E595 tests. The comparison provides general indications on the effects of temperature and time in relation to the ASTM test values obtained at 125 C for a 24-hour test duration.

  7. Analysis of gravimetric anomalies in Furnas caldera (São Miguel, Azores)

    NASA Astrophysics Data System (ADS)

    Montesinos, F. G.; Camacho, A. G.; Vieira, R.

    1999-09-01

    Furnas Volcano (São Miguel Island, Azores) is a steep-sided caldera complex resulting from several collapses. In this paper, we analyse and interpret the gravity survey carried out by the Instituto de Astronomı´a y Geodesia (Spain) and the gravity data published by the Instituto Nacional de Meteorologia e Geofisica (Portugal). The resulting Bouguer anomaly reveals the presence of a regional trend, several local features and a component of noise. In separating the regional trend we use a robust polynomial fitting. Further, a covariance analysis and a least squares prediction are applied to filter the noise and to model the local anomaly. A first signal map represents the main local anomaly, while the secondary signal map shows superficial anomalies. This distribution reveals a local main minimum close to the 1630 A.D. and Gaspar craters. Several possible alignments are shown that lead to a model, mainly with SW-NE and SE-NW orientations, of the negative anomaly, with the pattern of the low density zones showing a relationship with the volcanic features. Applying a stabilized linear method of gravimetric inversion, we obtain a density contrast distribution of the sources of the filtered local Bouguer anomaly, considering as unknowns the anomalous densities of a fixed discrete distribution of rectangular prisms which represents the subsoil volume. A mixed minimization criteria for the weighted residuals and the weighted density contrast allow us to obtain a solution as a discrete three-dimensional density contrast model. The obtained anomalous densities model shows a clear relation with the structure of the caldera complex and tectonic trends, with the principal body of negative contrast density being associated with the subsurface structure of the caldera.

  8. Gravimetric investigations on the North American Datum (1972 - 1973)

    NASA Technical Reports Server (NTRS)

    Mather, R. S.

    1975-01-01

    All the available unclassified gravity data on the North American Datum (NAD) and in the surrounding oceans was assembled late in 1972 for the investigation of the gravity field in North America and its relation to North American Datum 1927 (NAD 27). The gravity data in Canada and the United States was compiled on a common datum compatible with the International Gravity Standardization Network 1971 (IGSN 71). The variation in the error of representation in the region is studied along with the correlation characteristics of gravity anomalies with elevation. A free air geoid (FAG 73) was computed from a combination of surface gravity data and Goddard Earth Model (GEM) 4 and this was used as the basis for the computation of the non-Stokesian contributions to the height anomaly. The geocentric orientation parameters obtained by this astrogravimetric method are compared with those obtained by satellite techniques. The differences are found to be no greater than those between individual satellite solutions. The differences between the astrogravimetric solution and satellite solutions GSFC 73 and GEM 6 are studied in detail with a view to obtaining a better understanding of these discrepancies.

  9. Thermal device and method for production of carbon monoxide and hydrogen by thermal dissociation of hydrocarbon gases

    DOEpatents

    Detering, Brent A.; Kong, Peter C.

    2001-01-01

    Carbon monoxide is produced in a fast quench reactor. The production of carbon monoxide includes injecting carbon dioxide and some air into a reactor chamber having a high temperature at its inlet and a rapidly expanding a reactant stream, such as a restrictive convergent-divergent nozzle at its outlet end. Carbon dioxide and other reactants such as methane and other low molecular weight hydrocarbons are injected into the reactor chamber. Other gas may be added at different stages in the process to form a desired end product and prevent back reactions. The resulting heated gaseous stream is then rapidly cooled by expansion of the gaseous stream.

  10. Flexible supercapacitor based on polyaniline nanowires/carbon cloth with both high gravimetric and area-normalized capacitance

    NASA Astrophysics Data System (ADS)

    Horng, Ying-Ying; Lu, Yi-Chen; Hsu, Yu-Kuei; Chen, Chia-Chun; Chen, Li-Chyong; Chen, Kuei-Hsien

    Flexible supercapacitor is successfully fabricated using polyaniline nanowires/carbon cloth (PANI-NWs/CC) nanocomposite. High gravimetric capacitance of 1079 F g -1 at a specific energy of 100.9 Wh kg -1 and a specific power of 12.1 kW kg -1 is obtained. Moreover, this approach also offers an exceptionally high area-normalized capacitance of 1.8 F cm -2. The diffusion length of protons within the PANI-NWs is estimated to be about 60 nm by electrochemical impedance analysis, which indicates that the electrochemical performance of the electrode is not limited by the thickness of PANI-NWs. The electrochemical performance of PANI-NWS/CC remains without any deterioration, even when the cell is bent under high curvature. These results clearly present a cost-effective and simple method of fabrication of the nanostructured polymers with enormous potential in flexible energy storage device applications.

  11. A method for the speciation of diesel fuel and the semi-volatile hydrocarbon fraction of diesel-fueled vehicle exhaust emissions

    SciTech Connect

    Hammerle, R.H.; Siegl, W.O.; Herrmann, H.M.; Wenclawiak, B.W.

    1995-12-31

    Although much has been learned in recent years about the atmospheric reactivity of the hydrocarbon (HC) emissions from gasoline-fueled vehicles, there is only a limited database of corresponding information for exhaust emissions from diesel-fueled vehicles. An assessment of exhaust reactivity requires speciation, or measurement of the individual species of the HC fraction. The HC exhaust emissions are a complex mixture of unburned and partially burned fuel components. Because diesel fuel contains a much higher molecular weight range (typically C{sub 9}-C{sub 26}) than gasoline (typically C{sub 5}-C{sub 12}), new methodology was required to accommodate the collection and analysis of the >C{sub 12} fraction of the HC exhaust. As part of a study of the effects of fuel and other factors on the chemical nature of diesel emissions, the authors have developed a method for the collection and analysis of the semi-volatile or heavy HC (>C{sub 12}) fraction of the exhaust. The method has a sensitivity for individual HC species of 0.2 ng/L of dilute exhaust. In this report they describe the method and its application to fuel and exhaust analysis. Speciation results are presented for two fuels and for the heavy hydrocarbon fraction of the exhaust from selected vehicle tests.

  12. Development, optimization, validation and application of faster gas chromatography - flame ionization detector method for the analysis of total petroleum hydrocarbons in contaminated soils.

    PubMed

    Zubair, Abdulrazaq; Pappoe, Michael; James, Lesley A; Hawboldt, Kelly

    2015-12-18

    This paper presents an important new approach to improving the timeliness of Total Petroleum Hydrocarbon (TPH) analysis in the soil by Gas Chromatography - Flame Ionization Detector (GC-FID) using the CCME Canada-Wide Standard reference method. The Canada-Wide Standard (CWS) method is used for the analysis of petroleum hydrocarbon compounds across Canada. However, inter-laboratory application of this method for the analysis of TPH in the soil has often shown considerable variability in the results. This could be due, in part, to the different gas chromatography (GC) conditions, other steps involved in the method, as well as the soil properties. In addition, there are differences in the interpretation of the GC results, which impacts the determination of the effectiveness of remediation at hydrocarbon-contaminated sites. In this work, multivariate experimental design approach was used to develop and validate the analytical method for a faster quantitative analysis of TPH in (contaminated) soil. A fractional factorial design (fFD) was used to screen six factors to identify the most significant factors impacting the analysis. These factors included: injection volume (μL), injection temperature (°C), oven program (°C/min), detector temperature (°C), carrier gas flow rate (mL/min) and solvent ratio (v/v hexane/dichloromethane). The most important factors (carrier gas flow rate and oven program) were then optimized using a central composite response surface design. Robustness testing and validation of model compares favourably with the experimental results with percentage difference of 2.78% for the analysis time. This research successfully reduced the method's standard analytical time from 20 to 8min with all the carbon fractions eluting. The method was successfully applied for fast TPH analysis of Bunker C oil contaminated soil. A reduced analytical time would offer many benefits including an improved laboratory reporting times, and overall improved clean up

  13. Integrated analysis of seismological, gravimetric and structural data for identification of active faults geometries in Abruzzo and Molise areas (Italy)

    NASA Astrophysics Data System (ADS)

    Gaudiosi, Germana; Nappi, Rosa; Alessio, Giuliana; Porfido, Sabina; Cella, Federico; Fedi, Maurizio; Florio, Giovanni

    2015-04-01

    detected. The main results of our integrated analysis show a strong correlation among faults, hypocentral location of earthquakes and MDA lineaments from gravity data. Furthermore 2D seismic hypocentral locations together with high-resolution analysis of gravity anomalies have been correlated to estimate the fault systems parameters (strike, dip direction and dip angle) of some structures of the areas, through the application of the DEXP method (Fedi M. and M. Pilkington, 2012). References Fedi M., Cella F., Florio G., Rapolla A.; 2005: Multiscale Derivative Analysis of the gravity and magnetic fields of the Southern Apennines (Italy). In: Finetti I.R. (ed), CROP PROJECT: Deep Seismic Exploration of the Central Mediterranean and Italy, pp. 281-318. Fedi M., Pilkington M.; 2012: Understanding imaging methods for potential field data. Geophysics, 77: G13-G24. Gaudiosi G., Alessio G., Cella F., Fedi M., Florio G., Nappi, R.; 2012: Multiparametric data analysis for seismic sources identification in the Campanian area: merging of seismological, structural and gravimetric data. BGTA,. Vol. 53, n. 3, pp. 283-298.

  14. Uncertainties in PM2.5 gravimetric and speciation measurements and what we can learn from them.

    PubMed

    Malm, William C; Schichtel, Bret A; Pitchford, Marc L

    2011-11-01

    The U.S. Environmental Protection Agency (EPA) and the federal land management community (National Park Service, United States Fish and Wildlife Service, United States Forest Service, and Bureau of Land Management) operate extensive particle speciation monitoring networks that are similar in design but are operated for different objectives. Compliance (mass only) monitoring is also carried out using federal reference method (FRM) criteria at approximately 1000 sites. The Chemical Speciation Network (CSN) consists of approximately 50 long-term-trend sites, with about another 250 sites that have been or are currently operated by state and local agencies. The sites are located in urban or suburban settings. The Interagency Monitoring of Protected Visual Environments (IMPROVE) monitoring network consists of about 181 sites, approximately 170 of which are in nonurban areas. Each monitoring approach has its own inherent monitoring limitations and biases. Determination of gravimetric mass has both negative and positive artifacts. Ammonium nitrate and other semivolatiles are lost during sampling, whereas, on the other hand, measured mass includes particle-bound water. Furthermore, some species may react with atmospheric gases, further increasing the positive mass artifact. Estimating aerosol species concentrations requires assumptions concerning the chemical form of various molecular compounds, such as nitrates and sulfates, and organic material and soil composition. Comparing data collected in the various monitoring networks allows for assessing uncertainties and biases associated with both negative and positive artifacts of gravimetric mass determinations, assumptions of chemical composition, and biases between different sampler technologies. All these biases are shown to have systematic seasonal characteristics. Unaccounted-for particle-bound water tends to be higher in the summer, as does nitrate volatilization. The ratio of particle organic mass divided by organic

  15. Simultaneously high gravimetric and volumetric methane uptake characteristics of the metal-organic framework NU-111

    SciTech Connect

    Peng, Y; Srinivas, G; Wilmer, CE; Eryazici, I; Snurr, RQ; Hupp, JT; Yildirim, T; Farha, OK

    2013-01-01

    We show that the MOF NU-111 exhibits equally high volumetric and gravimetric methane uptake values, both within approximate to 75% of the DOE targets at 300 K. Upon reducing the temperature to 270 K, the uptake increases to 0.5 g g(-1) and 284 cc(STP) per cc at 65 bar. Adsorption of CO2 and H-2 is also reported. Simulated isotherms are in excellent agreement with those obtained from experiments.

  16. Preliminary estimates of Gulf Stream characteristics from TOPEX data and a precise gravimetric geoid

    NASA Technical Reports Server (NTRS)

    Rapp, Richard H.; Smith, Dru A.

    1994-01-01

    TOPEX sea surface height data has been used, with a gravimetric geoid, to calculate sea surface topography across the Gulf Stream. This topography was initially computed for nine tracks on cycles 21 to 29. Due to inaccurate geoid undulations on one track, results for eight tracks are reported. The sea surface topography estimates were used to calculate parameters that describe Gulf Stream characteristics from two models of the Gulf Stream. One model was based on a Gaussian representation of the velocity while the other was a hyperbolic representation of velocity or the sea surface topography. The parameters of the Gaussian velocity model fit were a width parameter, a maximum velocity value, and the location of the maximum velocity. The parameters of the hyperbolic sea surface topography model were the width, the height jump, position, and sea surface topography at the center of the stream. Both models were used for the eight tracks and nine cycles studied. Comparisons were made between the width parameters, the maximum velocities, and the height jumps. Some of the parameter estimates were found to be highly (0.9) correlated when the hyperbolic sea surface topography fit was carried out, but such correlations were reduced for either the Gaussian velocity fits or the hyperbolic velocity model fit. A comparison of the parameters derived from 1-year TOPEX data showed good agreement with values derived by Kelly (1991) using 2.5 years of Geosat data near 38 deg N, 66 deg W longitude. Accuracy of the geoid undulations used in the calculations was of order of +/- 16 cm with the accuracy of a geoid undulation difference equal to +/- 15 cm over a 100-km line in areas with good terrestrial data coverage. This paper demonstrates that our knowledge or geoid undulations and undulation differences, in a portion of the Gulf Stream region, is sufficiently accurate to determine characteristics of the jet when used with TOPEX altimeter data. The method used here has not been shown to

  17. Crumpled Nitrogen-Doped Graphene for Supercapacitors with High Gravimetric and Volumetric Performances.

    PubMed

    Wang, Jie; Ding, Bing; Xu, Yunling; Shen, Laifa; Dou, Hui; Zhang, Xiaogang

    2015-10-14

    Graphene is considered a promising electrochemical capacitors electrode material due to its high surface area and high electrical conductivity. However, restacking interactions between graphene nanosheets significantly decrease the ion-accessible surface area and impede electronic and ionic transfer. This would, in turn, severely hinder the realization of high energy density. Herein, we report a strategy for preparation of few-layer graphene material with abundant crumples and high-level nitrogen doping. The two-dimensional graphene nanosheets (CNG) feature high ion-available surface area, excellent electronic and ion transfer properties, and high packing density, permitting the CNG electrode to exhibit excellent electrochemical performance. In ionic liquid electrolyte, the CNG electrode exhibits gravimetric and volumetric capacitances of 128 F g(-1) and 98 F cm(-3), respectively, achieving gravimetric and volumetric energy densities of 56 Wh kg(-1) and 43 Wh L(-1). The preparation strategy described here provides a new approach for developing a graphene-based supercapacitor with high gravimetric and volumetric energy densities. PMID:26399912

  18. TRACE ANALYSIS FOR AROMATIC HYDROCARBONS IN NATURAL WATERS

    EPA Science Inventory

    A method of trace analysis of volatile aromatic hydrocarbons in natural water is described. The method is based on sparging water samples with nitrogen, adsorption of hydrocarbons on activated charcoal, followed by desorption into carbon disulfide and gas chromatographic analysis...

  19. Sulfur removal from hydrocarbons

    SciTech Connect

    Pearce, R.L.; Wolcott, R.A.

    1989-02-28

    A method is described for treating liquid and gaseous hydrocarbon streams containing H/sub 2/S, CO/sub 2/ and COS to remove a substantial portion of the H/sub 2/S and COS, and slip a substantial portion of the CO/sub 2/ which comprises: contacting the hydrocarbon stream containing H/sub 2/S, CO/sub 2/ and COS with a solution of methyldiethanolamine, which is a selective absorbent for H/sub 2/S with respect to CO/sub 2/, and which solution also contains diisopropanolamine, an organic liquid COS absorbent which absorbent converts by hydrolysis the COS to H/sub 2/S and CO/sub 2/.

  20. THERMOCHEMISTRY OF HYDROCARBON RADICALS

    SciTech Connect

    Kent M. Ervin, Principal Investigator

    2004-08-17

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

  1. H-H, C-H, and C-C NMR spin-spin coupling constants calculated by the FP-INDO method for aromatic hydrocarbons

    NASA Technical Reports Server (NTRS)

    Long, S. A. T.; Memory, J. D.

    1978-01-01

    The FP-INDO (finite perturbation-intermediate neglect of differential overlap) method is used to calculate the H-H, C-H, and C-C coupling constants in hertz for molecules of six different benzenoid hydrocarbons: benzene, naphthalene, biphenyl, anthracene, phenanthrene, and pyrene. The calculations are based on both the actual and the average molecular geometries. It is found that only the actual molecular geometries can always yield the correct relative order of values for the H-H coupling constants. For the calculated C-C coupling constants, as for the calculated C-H coupling constants, the signs are positive (negative) for an odd (even) number of bonds connecting the two nuclei. Agreements between the calculated and experimental values of the coupling constants for all six molecules are comparable to those reported previously for other molecules.

  2. Carbonaceous species methods comparison study at Citrus College. Task: analysis for trace hydrocarbons and related halocarbons in urban ambient air samples. Final report

    SciTech Connect

    Rasmussen, R.A.

    1987-10-01

    As part of the ARB-sponsored Carbonaceous Species Methods Comparison Study (CSMCS) in Glendora, CA, from August 11-21, 1986, time-integrated, ambient samples were collected in stainless steel canisters. Five samples per day were collected, ranging from 4 to 8 hours according to the CSMCS protocol. The species measured included CO, CH/sub 4/, CO/sub 2/, H/sub 2/, and the C/sub 2/ through C10 hydrocarbons. In addition, N/sub 2/O, the halocarbons F-12, F-11, F-113, CHCl/sub 3/, CH/sub 3/CCl/sub 3/, CCl/sub 4/, C/sub 2/HCl/sub 3/ and C/sub 2/Cl/sub 4/ were measured. Four gas-chromatograph systems were used to quantify these species. The report contains tables of concentrations of the species measured at the South Coast Air Basin site during smoggy summer conditions.

  3. Biogeochemistry of Halogenated Hydrocarbons

    NASA Astrophysics Data System (ADS)

    Adriaens, P.; Gruden, C.; McCormick, M. L.

    2003-12-01

    Halogenated hydrocarbons originate from both natural and industrial sources. Whereas direct anthropogenic emissions to the atmosphere and biosphere are often easy to assess, particularly when they are tied to major industrial activities, the attribution of emissions to other human activities (e.g., biomass burning), diffuse sources (e.g., atmospheric discharge, run off), and natural production (e.g., soils, fungi, algae, microorganisms) are difficult to quantify. The widespread occurrence of both alkyl and aryl halides in groundwater, surface water, soils, and various trophic food chains, even those not affected by known point sources, suggests a substantial biogeochemical cycling of these compounds (Wania and Mackay, 1996; Adriaens et al., 1999; Gruden et al., 2003). The transport and reactive fate mechanisms controlling their reactivity are compounded by the differences in sources of alkyl-, aryl-, and complex organic halides, and the largely unknown impact of biogenic processes, such as enzymatically mediated halogenation of organic matter, fungal production of halogenated hydrocarbons, and microbial or abiotic transformation reactions (e.g., Asplund and Grimvall, 1991; Gribble, 1996; Watling and Harper, 1998; Oberg, 2002). The largest source may be the natural halogenation processes in the terrestrial environment, as the quantities detected often exceed the amount that can be explained by human activities in the surrounding areas ( Oberg, 1998). Since biogeochemical processes result in the distribution of a wide range of halogenated hydrocarbon profiles, altered chemical structures, and isomer distributions in natural systems, source apportionment (or environmental forensics) can often only be resolved using multivariate statistical methods (e.g., Goovaerts, 1998; Barabas et al., 2003; Murphy and Morrison, 2002).This chapter will describe the widespread occurrence of halogenated hydrocarbons, interpret their distribution and biogeochemical cycling in light of

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

    PubMed

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

    2006-12-01

    As a preliminary step to evaluating the acute neurobehavioral effects of hydrocarbon solvents and to establish a working model for extrapolating animal test data to humans, joint neurobehavioral/toxicokinetic studies were conducted which involved administering ethanol to rats and volunteers. The specific objectives of the present studies were to evaluate the acute central nervous system (CNS) effects of ethanol in rats and humans and to assess relationships between internal levels of exposure and behavioral effects. A more general objective was to validate a battery of neurobehavioral tests that could be used to carry out comparative studies in both species. Accordingly, a range of tests including standardized observational measures, spontaneous motor activity assessments and learned visual discrimination performance was utilized in rat studies to evaluate acute CNS effects. Groups of rats were given ethanol at levels of approximately 0.5, 1.0 or 2.0g/kg, with blood level measurements to verify internal doses. In a volunteer study, 12 healthy male subjects were given 0.65g/kg ethanol, a level approximating the limit for motor vehicle operation in The Netherlands, and neurobehavioral effects were measured prior to and 1 and 3h after ethanol administration, with a computerized neurobehavioral test battery. Blood and air measurements were made to quantify internal doses. Results of the behavioral tests in rats provided evidence of ethanol-induced changes in neuromuscular, sensori-motor, and activity domains. There were also significant changes in visual discrimination, particularly in the areas of general measures of responding and psychomotor speed. In humans there were small but statistically significant effects on learning and memory, psychomotor skills and attention. However, the effects were subtle and not all parameters within given domains were affected. These studies demonstrated a qualitative similarity in response between rats and humans. PMID:16831461

  5. Development of a one-step integrated pressurized liquid extraction and cleanup method for determining polycyclic aromatic hydrocarbons in marine sediments.

    PubMed

    Choi, Minkyu; Kim, Ye-Jung; Lee, In-Seok; Choi, Hee-Gu

    2014-05-01

    A rapid and accurate one-step integrated pressurized liquid extraction (PLE) and cleanup method was developed and validated for 34 polycyclic aromatic hydrocarbons in marine sediments, giving an extract that could be analyzed by gas chromatography-mass spectrometry without further cleanup. Marine sediment (5 g) was loaded into the stainless-steel extraction cell above activated copper (5 g) and activated silica gel (5 g). An extraction temperature of 100°C and two 5 min extraction cycles using a 4:1 (v/v) hexane-dichloromethane mixture gave a good extraction efficiency. The integrated method gave extracts that were as clean as those obtained using PLE, followed by separate activated copper and silica gel cleanups. The method was validated, in terms of its accuracy, precision, and application using a certified reference material (NIST SRM 1944), marine sediments spiked at low and high concentrations, and contaminated harbor sediments. The mean recoveries were 92% and 94% for the low and high spike concentrations, respectively, and the accuracy was good (giving a mean of 86% of the certified reference material concentrations). The method developed gave a precision and accuracy equal to or better than the precision and accuracy found using PLE with separate cleanups. The method developed gives a shorter sample preparation time and uses much less solvent than PLE and separate cleanups. PMID:24671040

  6. Thermo Gravimetric and Differential Thermal Analysis of Clay of Western Rajasthan (india)

    NASA Astrophysics Data System (ADS)

    Shekhawat, M. S.

    The paper presents the study of thermo gravimetric and differential thermal analysis of blended clay. Western part of Rajasthan (India) is rich resource of Ball clays and it is mainly used by porcelain, sanitary ware, and tile industry. The quality and grade of clay available in the region vary from one deposit to other. To upgrade the fired colour and strength properties, different variety of clays may be blended together. The paper compares the results of thermal analysis one of blended clay B2 with reference clay of Ukraine which is imported by industries owners. The result revealed that the blended clay is having mineral kaolinite while the Ukrainian clay is Halloysite.

  7. Аbout possibility of linear interpolation interval extension for total terrain reduction in processing of massive arrays of gravimetric data

    NASA Astrophysics Data System (ADS)

    Mareev, Artem

    2015-04-01

    Highly accurate quasi-geoid modeling requires free-air gravity anomaly with dense distribution of gravimetric information in modeling regions. Due to strong correlation between free-air gravity anomaly and topography, topographic reduction is necessary for indirect anomalies interpolation for areas where gravimetric information is scarce. Processing of large amounts of points by numerical integration is time-consuming and requires significant computational power. Selection of correction parameters, which linearly change in certain interval, allows simplification of total terrain reduction processing. This approach extends linear interpolation interval of intermediate layer correction, according to performed experiments. Thus interval may be increased tenfold without loss of computational accuracy. Digital terrain model ETOPO1 was used in the experiments for terrain reduction. Profile was located between 55° and 40° parallels with longitude 90°. The profile crosses foothill and mountain areas with significant heights alterations. Total terrain correction for farther domain was computed by numerical integration method for points of regular grid with 1'step as well as integral correction parameters. Then changing step, which aliquots 2, for 2 to 12 angular minutes on regular grid points, theintegral correction parameters were interpolated between current and subsequent points. The value of terrain correction for farther domain obtained using integral correctional parameters was compared with directly computed correction. Obtained correction errors belong to interval from 0.56 to 2 μGal. Step of 10 angular minutes corresponds to root-mean-square error of 1.35 μGal. In other words, linear interpolation interval extension by means of integral correction parameters is feasible, and errors of linear interpolation do not exceed gravimetric measurements errors. This approach allows reducing computation time and keeps high accuracy of numerical integration method in

  8. Steam Hydrocarbon Cracking and Reforming

    ERIC Educational Resources Information Center

    Golombok, Michael

    2004-01-01

    The interactive methods of steam hydrocarbon reforming and cracking of the oil and chemical industries are scrutinized, with special focus on their resemblance and variations. The two methods are illustrations of equilibrium-controlled and kinetically-controlled processes, the analysis of which involves theories, which overlap and balance each…

  9. Development of an ionic liquid based dispersive liquid-liquid microextraction method for the analysis of polycyclic aromatic hydrocarbons in water samples.

    PubMed

    Pena, M Teresa; Casais, M Carmen; Mejuto, M Carmen; Cela, Rafael

    2009-09-01

    A simple, rapid and efficient method, ionic liquid based dispersive liquid-liquid microextraction (IL-DLLME), has been developed for the first time for the determination of 18 polycyclic aromatic hydrocarbons (PAHs) in water samples. The chemical affinity between the ionic liquid (1-octyl-3-methylimidazolium hexafluorophosphate) and the analytes permits the extraction of the PAHs from the sample matrix also allowing their preconcentration. Thus, this technique combines extraction and concentration of the analytes into one step and avoids using toxic chlorinated solvents. The factors affecting the extraction efficiency, such as the type and volume of ionic liquid, type and volume of disperser solvent, extraction time, dispersion stage, centrifuging time and ionic strength, were optimised. Analysis of extracts was performed by high performance liquid chromatography (HPLC) coupled with fluorescence detection (Flu). The optimised method exhibited a good precision level with relative standard deviation values between 1.2% and 5.7%. Quantification limits obtained for all of these considered compounds (between 0.1 and 7 ng L(-1)) were well below the limits recommended in the EU. The extraction yields for the different compounds obtained by IL-DLLME, ranged from 90.3% to 103.8%. Furthermore, high enrichment factors (301-346) were also achieved. The extraction efficiency of the optimised method is compared with that achieved by liquid-liquid extraction. Finally, the proposed method was successfully applied to the analysis of PAHs in real water samples (tap, bottled, fountain, well, river, rainwater, treated and raw wastewater). PMID:19646707

  10. Production of hydrocarbons from hydrates. [DOE patent application

    DOEpatents

    McGuire, P.L.

    1981-09-08

    An economical and safe method of producing hydrocarbons (or natural gas) from in situ hydrocarbon-containing hydrates is given. Once started, the method will be self-driven and will continue producing hydrocarbons over an extended period of time (i.e., many days).

  11. Study of alumosilicate porcelains: Sol-gel preparation, characterization and erosion evaluated by gravimetric method

    SciTech Connect

    Bogdanoviciene, Irma; Jankeviciute, Audrone; Pinkas, Jiri; Beganskiene, Aldona; Kareiva, Aivaras

    2008-11-03

    In this paper, the sol-gel synthesis and characteristic properties of kalsilite-type alumosilicates (KAlSiO{sub 4} and K{sub 0.5}Na{sub 0.5}AlSiO{sub 4}) are reported. The polycrystalline powders were characterized by thermal analysis (TG/DTA), powder X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). Single-phase kalsilite oxides have been obtained after annealing precursor gels for 5 h in the temperature range of 750-850 deg. C. It was demonstrated that crystallinity of the samples slightly depends on the temperature of annealing. From the results obtained, it could be concluded that the KAlSiO{sub 4} solids are composed of the volumetric plate-like grains with no regular size (from 5 {mu}m to 30 {mu}m at 750 deg. C and around 5-50 {mu}m at 850 deg. C). Larger crystallites for mixed potassium-sodium kalsilite have formed (from 10 {mu}m to 80 {mu}m at 750 deg. C and >100 {mu}m at 850 deg. C) in comparison with potassium kalsilite samples). The erosion of obtained dental porcelain samples stored in saliva, beer and Coca-Cola was compared.

  12. Improved Gravimetric Geoid Model for Japan From Terrestrial Data and Altimetric Gravity Model

    NASA Astrophysics Data System (ADS)

    Kuroishi, Y.

    2003-12-01

    An improved gravimetric geoid model for Japan is developed by combining an altimetric gravity model, KMS02 with terrestrial gravity data. Additional terrestrial gravity data were newly obtained in some data gaps for previous geoid models: ship data in the western part of Seto Inland Sea and land gravity data in south and east Hokkaido, where the latest gravimetric geoid model for Japan, JGEOID2000 shows relatively large errors at short wavelengths. In addition, medium wavelength signals of gravity from KMS02 are retrieved and combined by filtering based on wavelets. The combination significantly reduces systematic errors of JGEOID2000 gravity/geoid models derived from ship data, at medium wavelengths around Hokkaido Island. Moreover, recently-released global geopotential models from the GRACE mission, EIGEN-GRACE01S by GFZ and GGM01 by CSR are used as a foundation for 1D-FFT computation of Stokes integral in a remove-restore manner. Those models themselves show improved performance over the Japanese islands in terms of geoid heights when compared with GPS/leveling geoid heights throughout the islands. When we change the maximum degree of the spherical harmonics used and merge them with higher degree harmonics of EGM96 (up to degree and order 360), those geopotential models seem to work best at degree 90. Resulting geoid models are compared and evaluated with GPS/leveling geoid heights.

  13. High-sensitivity open-loop electronics for gravimetric acoustic-wave-based sensors.

    PubMed

    Rabus, David; Friedt, Jean-Michel; Ballandras, Sylvain; Martin, Gilles; Carry, Emile; Blondeau-Patissier, Virginie

    2013-06-01

    Detecting chemical species in gas phase has recently received an increasing interest mainly for security control, trying to implement new systems allowing for extended dynamics and reactivity. In this work, an open-loop interrogation strategy is proposed to use radio-frequency acoustic transducers as micro-balances for that purpose. The resulting system is dedicated to the monitoring of chemical compounds in gaseous or liquid-phase state. A 16 Hz standard deviation is demonstrated at 125 MHz, with a working frequency band in the 60 to 133 MHz range, answering the requirements for using Rayleigh- and Love-wave-based delay lines operating with 40-μm acoustic wavelength transducers. Moreover, this electronic setup was used to interrogate a high-overtone bulk acoustic wave resonator (HBAR) microbalance, a new sensor class allowing for multi-mode interrogation for gravimetric measurement improvement. The noise source still limiting the system performance is due to the analog-to-digital converter of the microcontroller, thus leaving open degrees-of-freedom for improving the obtained results by optimizing the voltage reference and board layout. The operation of the system is illustrated using a calibrated galvanic deposition at the surface of Love-wave delay lines to assess theoretical predictions of their gravimetric sensitivity and to compare them with HBAR-based sensor sensitivity. PMID:25004485

  14. Least squares collocation applied to local gravimetric solutions from satellite gravity gradiometry data

    NASA Technical Reports Server (NTRS)

    Robbins, J. W.

    1985-01-01

    An autonomous spaceborne gravity gradiometer mission is being considered as a post Geopotential Research Mission project. The introduction of satellite diometry data to geodesy is expected to improve solid earth gravity models. The possibility of utilizing gradiometer data for the determination of pertinent gravimetric quantities on a local basis is explored. The analytical technique of least squares collocation is investigated for its usefulness in local solutions of this type. It is assumed, in the error analysis, that the vertical gravity gradient component of the gradient tensor is used as the raw data signal from which the corresponding reference gradients are removed to create the centered observations required in the collocation solution. The reference gradients are computed from a high degree and order geopotential model. The solution can be made in terms of mean or point gravity anomalies, height anomalies, or other useful gravimetric quantities depending on the choice of covariance types. Selected for this study were 30 x 30 foot mean gravity and height anomalies. Existing software and new software are utilized to implement the collocation technique. It was determined that satellite gradiometry data at an altitude of 200 km can be used successfully for the determination of 30 x 30 foot mean gravity anomalies to an accuracy of 9.2 mgal from this algorithm. It is shown that the resulting accuracy estimates are sensitive to gravity model coefficient uncertainties, data reduction assumptions and satellite mission parameters.

  15. A new technique to assess dermal absorption of volatile chemicals in vitro by thermal gravimetric analysis.

    PubMed

    Rauma, Matias; Isaksson, Tina S; Johanson, Gunnar

    2006-10-01

    Potential health hazards of dermal exposure, variability in reported dermal absorption rates and potential losses from the skin by evaporation indicate a need for a simple, inexpensive and standardized procedure to measure dermal absorption and desorption of chemical substances. The aim of this study was to explore the possibility to measure dermal absorption and desorption of volatile chemicals using a new gravimetric technique, namely thermal gravimetric analysis (TGA), and trypsinated stratum corneum from pig. Changes in skin weight were readily detected before, during and after exposure to vapours of water, 2-propanol, methanol and toluene. The shape and height of the weight curves differed between the four chemicals, reflecting differences in diffusivity and partial pressure and skin:air partitioning, respectively. As the skin weight is highly sensitive to the partial pressure of volatile chemicals, including water, this technique requires carefully controlled conditions with respect to air flow, temperature, chemical vapour generation and humidity. This new technique may help in the assessment of dermal uptake of volatile chemicals. Only a small piece of skin is needed and skin integrity is not necessary, facilitating the use of human samples. The high resolution weight-time curves obtained may also help to elucidate the characteristics of absorption, desorption and diffusion of chemicals in skin. PMID:16631342

  16. Uncertainty estimates for the gravimetric primary flow standards of the MRF

    SciTech Connect

    Park, J.T.; Behring, K.A. II; Grimley, T.A.

    1995-12-31

    Two gravimetric flow standards for mass flowrate are in operation for the calibration of high capacity flowmeters with natural gas. Both systems measure mass electronically from scales which operate on a gyroscopic principle. The gravimetric provers are an integral part of the Gas Research Institute (GRI) Metering Research Facility (MRF) and can provide a direct primary calibration for any conventional gas flowmeter. The smaller system is attached to the Low Pressure Loop (LPL) with an operating pressure of 0.14 to 1.4 MPa (20 to 200 psia) and a flowrate up to 4.6 kg/s (10 lbm/s). The larger system is connected to the High Pressure Loop (HPL) with pressures of 1.4 to 10 MPa (200 to 1,455 psia) and flows to 43 kg/s (95 lbm/s). The performance of these two standards and their estimated uncertainties are described. The optimal total uncertainty in mass flowrate is {plus_minus}0.01% and {plus_minus}0.02%, respectively, for the LPL and HPL. The actual uncertainty is dependent on the operating conditions and is primarily a function of the operating pressure and flowrate. Uncertainty estimates are provided on the calibration of turbine meters and sonic nozzles. The largest uncertainty in the calibration of flowmeters is the uncertainty in theoretical models for density and the measurement of natural gas composition.

  17. Efficacy of head space solid-phase microextraction coupled to gas chromatography-mass spectrometry method for determination of the trace extracellular hydrocarbons of cyanobacteria.

    PubMed

    Guan, Wenna; Zhu, Tao; Wang, Yuejie; Zhang, Zhongyi; Jin, Zhao; Wang, Cong; Bai, Fali

    2016-09-01

    Hydrocarbons are widespread in cyanobacteria, and the biochemical synthetic pathways were recently identified. Intracellular fatty alka(e)nes of cyanobacteria have been detected by liquid-liquid extraction (LLE) coupled to gas chromatography-mass spectrometry (GC/MS). However, whether fatty alka(e)nes can be released to cyanobacterial culture media remains to be clarified. This work develops a sensitive method for analyzing the trace level of extracellular hydrocarbons in cyanobacterial culture media by head space solid-phase microextraction (HS-SPME) coupled to GC/MS. Headspace (HS) extraction mode using polydimethylsiloxane fiber to extract for 30min at 50°C was employed as the optimal extraction conditions. Five cyanobacterial fatty alka(e)nes analogs including pentadecene (C15:1), pentadecane (C15:0), heptadecene (C17:1), heptadecane (C17:0), nonadecane (C19:0) were analyzed, and the data obtained from HS-SPME-GC/MS method were quantified using internal standard peak area comparisons. Limits of detection (LOD), limits of quantitation (LOQ), linear dynamic range, precisions (RSD) and recovery for the analysis of extracellular fatty alka(e)nes of cyanobacteria by HS-SPME-GC/MS were evaluated. The LODs limits of detection (S/N = 3) varied from 10 to 21 ng L-1. The correlation coefficients (r) of the calibration curves ranged from 0.9873 to 0.9977 with a linearity from 0.1 to 50 μg L-1. The RSD values were ranging from 7.8 to 14.0% and from 4.0 to 8.8% at 1.0 μg L-1 and 10.0 μg L-1 standard solutions, respectively. Comparative analysis of extracellular fatty alka(e)nes in the culture media of model cyanobacteria Synechocystis sp. PCC 6803 demonstrated that sensitivity of HS-SPME-GC/MS method was significantly higher than LLE method. Finally, we found that heptadecane can be released into the culture media of Synechocystis sp. PCC 6803 at the later growth period. PMID:27428454

  18. Gas chromatography-mass spectrometry (GC-MS) method for the determination of 16 European priority polycyclic aromatic hydrocarbons in smoked meat products and edible oils.

    PubMed

    Jira, W; Ziegenhals, K; Speer, K

    2008-06-01

    A gas chromatography-mass spectrometry (GC-MS) method was developed for the analysis of 15 polycyclic aromatic hydrocarbons (PAHs) highlighted as carcinogenic by the Scientific Committee on Food (SCF) plus benzo[c]fluorine (recommended to be analysed by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in fat-containing foods such as edible oils and smoked meat products. This method includes accelerated solvent extraction (ASE) and the highly automated clean-up steps gel permeation chromatography (GPC) and solid-phase extraction (SPE). Using a VF-17ms GC column, a good separation of benzo[b]fluoranthene, benzo[j]fluoranthene and benzo[k]fluoranthene was achieved. Futhermore, the six methylchrysene isomers and the PAH compounds with a molecular weight of 302 Daltons in fat-containing foods attained a better chromatographic separation in comparison with a 5-ms column. The reliability of the analytical method for edible oils was demonstrated by the results from a proficiency test. Measurements with GC-high-resolution mass spectroscopy (HRMS) and gas chromatography-mass selective detection (GC-MSD) led to comparable results. A survey of the 16 PAHs in 22 smoked meat products showed concentrations in the range < 0.01-19 microg kg(-1). The median concentration for benzo[a]pyrene was below 0.15 microg kg(-1). PMID:18630343

  19. A review of analytical methods for the identification and quantification of hydrocarbons found in jet propellant 8 and related petroleum based fuels.

    PubMed

    Gregg, Shonetta D; Fisher, Jeffrey W; Bartlett, Michael G

    2006-01-01

    Jet propellant 8 (JP-8) is a complex mixture of compounds that varies from batch to batch. Quantification of various compound classes of JP-8, including BTEX, PAHs and VOCs, has been accomplished. Very few papers have tackled total JP-8 quantification because of its complexity. The components in JP-8 tend to co-elute and present at low concentrations, often nondetectable. JP-8 is the major source of chemical exposure for Department of Defense personnel and a potential hazard for civilians and marine animals. Some components of JP-8 have been identified as possible human carcinogens and have been studied extensively. Development of analytical methods to analyze the components of this fuel are essential to measure the extent of exposure, as well as the short-term and long-term exposure in rodents, humans and marine life. To date, JP-8 has been examined in urine, blood, contaminated water and fish tissue. This paper reviews methods currently utilized in the literature for the analysis of JP-8 and its components. This paper also discusses extraction methods and detectors commonly used in JP-8 and hydrocarbon analysis in general. Finally, the effects of exposure and the future of JP-8 and petroleum analysis with respect to human health are discussed. PMID:16779790

  20. Gravimetric response of water table fluctuations in the Sahelian Diffa site (East Niger): local effects including poro-elasticity

    NASA Astrophysics Data System (ADS)

    Hector, B.; Genthon, P.; Le Coz, M.; Hinderer, J.; Chalikakis, K.; Descloitres, M.

    2010-12-01

    The GHYRAF project (Gravimetry and HYdrology in AFrica) is devoted to a regional study of the relationship between hydrological and gravimetric signals in the Western African Monsoon area. Three sites are monitored in a decreasing pluviometric gradient: Djougou (North Benin), Wankama (Niamey area) and Bagara (Eastern Niger) with annual rainfalls amounting to 1200 mm, 600 mm and 350 mm, respectively. The Diffa/Bagara site is located 640m away from the Yobé temporary river, a tributary of Lake Chad fed by rainfall on the Jos Plateau (Nigeria) and that is generally flowing between mid July and January. Apart from this period, the river bed includes a series of ponds that form the top of the aquifer and that are pumped for intensive irrigated cropping. The 50m thick uppermost unconfined aquifer is locally recharged by the Yobé River and is flowing northwards. It has been explored by geophysical methods involving RMS and TDEM soundings, which provided information on its porosity and electrical conductivity, respectively. A series of nearly 50 holes drilled down to a 10 m depth in the Bagara area allowed to define the detailed sedimentary structure of the aquifer. It consists mainly of fluvial deposits with alternating layers of fine sands, coarse grained sands and clays. The sedimentary pile includes clayed layer of centimetric to metric thickness with a mean lateral extension of 300 m. The groundwater level is monitored by a series of 4 piezometers located at 25 m, 270 m, 500 m and 640 m from the river axis. The shape of the piezometric curve at the Bagara station is 0.4 m amplitude sinusoid and presents a maximum level at mid January and a minimum one near mid July. Clearly, water level fluctuations are governed by infiltration from the Yobe river with an offset controlled by the distance to it. With the 20% porosity measured by MRS, this would imply a nearly 30 nms-2 gravimetric signal, which is in fair agreement with the observed amplitude. However both the

  1. Assessment of factors influencing PM mass concentration measured by gravimetric & beta attenuation techniques at a suburban site

    NASA Astrophysics Data System (ADS)

    Triantafyllou, E.; Diapouli, E.; Tsilibari, E. M.; Adamopoulos, A. D.; Biskos, G.; Eleftheriadis, K.

    2016-04-01

    Near real-time atmospheric particulate matter (PM) monitors are extensively used in air quality networks given their ability to provide continuous measurements with minimal attention by the operator. Their principle of operation is based on measurement of a physical parameter that is quantitatively linked to the PM mass concentration. Significant discrepancies between these measurements and those obtained by the reference gravimetric method, conducted in regions with diverse climatic conditions, have been reported in the literature. In this study we compare systematic PM2.5 and PM10 gravimetric (GM) and beta attenuation (BA) measurements performed at a suburban site in Athens, Greece, over a period of 4 years (2009-2012). In general, BA and GM datasets exhibited similar temporal variation for both PM size fractions. An overestimation of the ΒΑ measurements, which was ∼30% for the PM2.5 and ∼10% for the PM10 data, was observed. Good linear correlations between GM and BA data were observed, with estimated Pearson coefficients being 0.79 for the PM2.5 and 0.85 for the PM10 measurements. The respective fitted equations through the entire dataset were BA = 0.71 GM + 6.2, and BA = 0.77 G M + 4.1. Better correlation between GM and BA measurements was observed during the cold rather than the warm period. Discrepancies between BA and GM PM2.5 measurements increased with increasing available water vapor, suggesting that the aerosol bound water has a strong effect on the measurements. The effect of filter material used for GM measurements (i.e., quartz, glass fiber, or Teflon) was also examined for the PM2.5 dataset. Best correlation between BA and GM data was observed when glass fiber, which is incidentally the material of the BA filter tape, was used in the GM measurements. When the BA to GM relationship was examined by further categorizing the data by the season (i.e., cold and warm period) for different filter types, the relationships that were fitted to the data

  2. EVALUATION OF FUSED-SILICA CAPILLARY COLUMNS FOR GC/ECD (GAS CHROMATOGRAPHY WITH ELECTRON CAPTURE DETECTION) ANALYSIS OF CHLORINATED HYDROCARBONS LISTED IN EPA (ENVIRONMENTAL PROTECTION AGENCY) METHOD 8120 (JOURNAL VERSION)

    EPA Science Inventory

    Four mega-bore, one wide-bore, and one narrow-bore fused-silica capillary columns were evaluated for their applicability to the GC/ECD analysis of 22 chlorinated hydrocarbons, some of which are currently targeted by EPA Method 8120. No one column can resolve all 22 compounds. Fou...

  3. Single-laboratory validation of a saponification method for the determination of four polycyclic aromatic hydrocarbons in edible oils by HPLC-fluorescence detection.

    PubMed

    Akdoğan, Abdullah; Buttinger, Gerhard; Wenzl, Thomas

    2016-01-01

    An analytical method is reported for the determination of four polycyclic aromatic hydrocarbons (benzo[a]pyrene (BaP), benz[a]anthracene (BaA), benzo[b]fluoranthene (BbF) and chrysene (CHR)) in edible oils (sesame, maize, sunflower and olive oil) by high-performance liquid chromatography. Sample preparation is based on three steps including saponification, liquid-liquid partitioning and, finally, clean-up by solid phase extraction on 2 g of silica. Guidance on single-laboratory validation of the proposed analysis method was taken from the second edition of the Eurachem guide on method validation. The lower level of the working range of the method was determined by the limits of quantification of the individual analytes, and the upper level was equal to 5.0 µg kg(-1). The limits of detection and quantification of the four PAHs ranged from 0.06 to 0.12 µg kg(-1) and from 0.13 to 0.24 µg kg(-1). Recoveries of more than 84.8% were achieved for all four PAHs at two concentration levels (2.5 and 5.0 µg kg(-1)), and expanded relative measurement uncertainties were below 20%. The performance of the validated method was in all aspects compliant with provisions set in European Union legislation for the performance of analytical methods employed in the official control of food. The applicability of the method to routine samples was evaluated based on a limited number of commercial edible oil samples. PMID:26634339

  4. Conversion of organic solids to hydrocarbons

    DOEpatents

    Greenbaum, E.

    1995-05-23

    A method of converting organic solids to liquid and gaseous hydrocarbons includes impregnating an organic solid with photosensitizing ions and exposing the impregnated solid to light in a non-oxidizing atmosphere for a time sufficient to photocatalytically reduce the solid to at least one of a liquid and a gaseous hydrocarbon. 5 Figs.

  5. Conversion of organic solids to hydrocarbons

    DOEpatents

    Greenbaum, Elias

    1995-01-01

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

  6. Evaluation of Polycyclic Aromatic Hydrocarbons Using Analytical Methods, Toxicology, and Risk Assessment Research: Seafood Safety after a Petroleum Spill as an Example

    PubMed Central

    Overton, Edward; Frickel, Scott; Howard, Jessi; Wilson, Mark; Simon, Bridget; Echsner, Stephen; Nguyen, Daniel; Gauthe, David; Blake, Diane; Miller, Charles; Elferink, Cornelis; Ansari, Shakeel; Fernando, Harshica; Trapido, Edward; Kane, Andrew

    2013-01-01

    Background: Polycyclic aromatic hydrocarbons (PAHs) are abundant and widespread environmental chemicals. They are produced naturally and through man-made processes, and they are common in organic media, including petroleum. Several PAHs are toxic, and a subset exhibit carcinogenic activity. PAHs represent a range of chemical structures based on two or more benzene rings and, depending on their source, can exhibit a variety of side modifications resulting from oxygenation, nitrogenation, and alkylation. Objectives: Here we discuss the increasing ability of contemporary analytical methods to distinguish not only different chemical structures among PAHs but also their concentrations in environmental media. Using seafood contamination following the Deepwater Horizon accident as an example, we identify issues that are emerging in the PAH risk assessment process because of increasing analytical sensitivity for individual PAHs, and we describe the paucity of toxicological literature for many of these compounds. Discussion: PAHs, including the large variety of chemically modified or substituted PAHs, are naturally occurring and may constitute health risks if human populations are exposed to hazardous levels. However, toxicity evaluations have not kept pace with modern analytic methods and their increased ability to detect substituted PAHs. Therefore, although it is possible to measure these compounds in seafood and other media, we do not have sufficient information on the potential toxicity of these compounds to incorporate them into human health risk assessments and characterizations. Conclusions: Future research efforts should strategically attempt to fill this toxicological knowledge gap so human health risk assessments of PAHs in environmental media or food can be better determined. This is especially important in the aftermath of petroleum spills. Citation: Wickliffe J, Overton E, Frickel S, Howard J, Wilson M, Simon B, Echsner S, Nguyen D, Gauthe D, Blake D, Miller C

  7. Development and evaluation of monitoring methods for polycyclic aromatic hydrocarbons in house dust and track-in soil. Final report, June 1992-September 1993

    SciTech Connect

    Chuang, J.C.; Callahan, P.J.; Katona, V.; Gordon, S.M.

    1993-09-01

    The analytical methods were developed for the determination of Polycyclic aromatic hydrocarbons (PAH) and Polychlorinated biphenyls (PCBs) in the dust and soil based on sonication with hexane and 10% ether/hexane, respectively, and analysis by gas chromatography/mass spectrometry (GC/MS). Quantitative recoveries of spiked perdeuterated PAH and (13)C labeled PCB were obtained using the above methods. In an eight-home field evaluation, the concentrations of the sum of all target PAH in the house dust ranged from 16 to 550 ppm, from 41 to 580 ppm, and from 25 to 310 ppm in the samples collected during June 1992, October 1992, and April 1993, respectively. The PCB concentrations were lower than PAH concentrations in all samples; the sum of all target PCB varied from 210 to 1900 ppb in house dust, from 30 to 880 ppb in entryway soil, from 16 to 500 ppb in pathway soil, and from 18 to 210 ppb in foundation soil. Higher PCB concentrations were found in house dust samples than in entryway soil samples. Similar PCB concentrations were observed in the pathway soil samples and the foundation soil samples, which were lower than PCB found in entryway soil samples.

  8. Validation of an Analytical Method for Determination of 13 priority polycyclic aromatic hydrocarbons in mineral water using dispersive liquid-liquid microextraction and GC-MS.

    PubMed

    Sadeghi, Ramezan; Kobarfard, Farzad; Yazdanpanah, Hassan; Eslamizad, Samira; Bayat, Mitra

    2016-01-01

    Dispersive liquid-liquid microextraction (DLLME) combined with gas chromatography-mass spectrometry (GC-MS) was used for the extraction and determination of 13 polycyclic aromatic hydrocarbons (PAHs) in mineral water samples. In this procedure, the suitable combination of extraction solvent (500 µL chloroform) and disperser solvent (1000 µL acetone) were quickly injected into the water sample (10.00 mL) by Hamilton syringe. After centrifugation, 500 µL of the lower organic phase was dried under a gentle stream of nitrogen, re-dissolved in chloroform and injected into GC-MS. Chloroform and acetone were found to be the best extraction and disperser solvent, respectively. Validation of the method was performed using spiked calibration curves. The enrichment factor ranged from 93 to 129 and the recovery ranged from 71 to 90%. The linear ranges for all the PAHs were 0.10-2.80 ngmL(-1). The relative standard deviations (RSDs) of PAHs in water by using anthracene-d10 as internal standard, were in the range of 4-11% for most of the analytes (n = 3). Limit of detection (LOD) for different PAHs were between 0.03 and 0.1 ngmL(-1). The method was successfully applied for the analysis of PAHs in mineral water samples collected from Tehran. PMID:27610156

  9. Validation of an Analytical Method for Determination of 13 priority polycyclic aromatic hydrocarbons in mineral water using dispersive liquid-liquid microextraction and GC-MS

    PubMed Central

    Sadeghi, Ramezan; Kobarfard, Farzad; Yazdanpanah, Hassan; Eslamizad, Samira; Bayat, Mitra

    2016-01-01

    Dispersive liquid-liquid microextraction (DLLME) combined with gas chromatography–mass spectrometry (GC–MS) was used for the extraction and determination of 13 polycyclic aromatic hydrocarbons (PAHs) in mineral water samples. In this procedure, the suitable combination of extraction solvent (500 µL chloroform) and disperser solvent (1000 µL acetone) were quickly injected into the water sample (10.00 mL) by Hamilton syringe. After centrifugation, 500 µL of the lower organic phase was dried under a gentle stream of nitrogen, re-dissolved in chloroform and injected into GC-MS. Chloroform and acetone were found to be the best extraction and disperser solvent, respectively. Validation of the method was performed using spiked calibration curves. The enrichment factor ranged from 93 to 129 and the recovery ranged from 71 to 90%. The linear ranges for all the PAHs were 0.10-2.80 ngmL-1. The relative standard deviations (RSDs) of PAHs in water by using anthracene-d10 as internal standard, were in the range of 4-11% for most of the analytes (n = 3). Limit of detection (LOD) for different PAHs were between 0.03 and 0.1 ngmL-1. The method was successfully applied for the analysis of PAHs in mineral water samples collected from Tehran. PMID:27610156

  10. Evaluation of sampling and analytical methods for nicotine and polynuclear aromatic hydrocarbon in indoor air. Final report, 1 February 1987-30 March 1987

    SciTech Connect

    Chuang, J.C.; Kuhlman, M.R.; Hannan, S.W.; Bridges, C.

    1987-11-01

    The objective of this project was to evaluate a potential collection medium, XAD-4 resin, for collecting nicotine and polynuclear aromatic hydrocarbon (PAH) and to determine whether one collection system and one analytical method will allow quantification of both compound classes in air. The extraction efficiency study was to determine the extraction method to quantitatively remove nicotine and PAH from XAD-4 resin. The results showed that a two-step Soxhlet extraction consisting of dichloromethane followed by ethyl acetate resulted in the best recoveries for both nicotine and PAH. In the sampling efficiency study, XAD-2 and XAD-4 resin were compared, in parallel, for collection of PAH and nicotine. Quartz fiber filters were placed upstream of both adsorbents to collect particles. Prior to sampling, both XAD-2 and XAD-4 traps were spiked with known amounts (2 microgram) of perdeuterated PAH and D3-nicotine. The experiments were performed with cigarette smoking and nonsmoking conditions. The spiked PAH were retained well in both adsorbents after exposure to more than 300 cu. m. of indoor air. The spiked XAD-4 resin gave higher recoveries for D3-nicotine than did the spiked XAD-2 resin. The collection efficiency for PAH for both adsorbents is very similar but higher levels of nicotine were collected on XAD-4 resin.

  11. A highly accurate absolute gravimetric network for Albania, Kosovo and Montenegro

    NASA Astrophysics Data System (ADS)

    Ullrich, Christian; Ruess, Diethard; Butta, Hubert; Qirko, Kristaq; Pavicevic, Bozidar; Murat, Meha

    2016-04-01

    The objective of this project is to establish a basic gravity network in Albania, Kosovo and Montenegro to enable further investigations in geodetic and geophysical issues. Therefore the first time in history absolute gravity measurements were performed in these countries. The Norwegian mapping authority Kartverket is assisting the national mapping authorities in Kosovo (KCA) (Kosovo Cadastral Agency - Agjencia Kadastrale e Kosovës), Albania (ASIG) (Autoriteti Shtetëror i Informacionit Gjeohapësinor) and in Montenegro (REA) (Real Estate Administration of Montenegro - Uprava za nekretnine Crne Gore) in improving the geodetic frameworks. The gravity measurements are funded by Kartverket. The absolute gravimetric measurements were performed from BEV (Federal Office of Metrology and Surveying) with the absolute gravimeter FG5-242. As a national metrology institute (NMI) the Metrology Service of the BEV maintains the national standards for the realisation of the legal units of measurement and ensures their international equivalence and recognition. Laser and clock of the absolute gravimeter were calibrated before and after the measurements. The absolute gravimetric survey was carried out from September to October 2015. Finally all 8 scheduled stations were successfully measured: there are three stations located in Montenegro, two stations in Kosovo and three stations in Albania. The stations are distributed over the countries to establish a gravity network for each country. The vertical gradients were measured at all 8 stations with the relative gravimeter Scintrex CG5. The high class quality of some absolute gravity stations can be used for gravity monitoring activities in future. The measurement uncertainties of the absolute gravity measurements range around 2.5 micro Gal at all stations (1 microgal = 10-8 m/s2). In Montenegro the large gravity difference of 200 MilliGal between station Zabljak and Podgorica can be even used for calibration of relative gravimeters

  12. Rapid and sensitive method for the determination of four EU marker polycyclic aromatic hydrocarbons in cereal-based foods using isotope-dilution GC/MS.

    PubMed

    Kacmaz, Sibel; Zelinkova, Zuzana; Wenzl, Thomas

    2016-04-01

    A rapid and sensitive method has been developed for the determination of the four European Union marker polycyclic aromatic hydrocarbons (PAHs; benz[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene) in some cereal-based foods. The method is based on pressurised liquid extraction (PLE), solid-phase extraction clean-up (SPE) and isotope-dilution gas chromatography with mass-spectrometric detection (GC/MS). The developed method was calibrated for the content range of 0.05-12.5 µg kg(-1) (expressed on a product basis). Recoveries of PAH were monitored in each sample via the recovery of (13)C-labelled PAHs. Recovery values were in the range between 86% and 91%, with relative standard deviations (RSDs) between 5% and 9%. The achieved limits of detection for all analytes were below 0.05 µg kg(-1). The applicability of the method for the analysis of routine samples was studied by the analysis of a set of commercial bread and breakfast cereal samples. In all analysed samples, benzo[a]pyrene (BAP) was the most prevalent PAH with the content between 0.09 and 0.30 µg kg(-1). On average, samples showed low levels of the sum of the four EU marker PAHs (ΣPAH4) that ranged between 0.11 and 0.22 µg kg(-1) for bread samples and between 0.23 and 0.87 µg kg(-1) for breakfast cereal samples. The developed method was found suitable for the determination of PAHs in cereal-based foods like cornflakes and breads with total relative fat contents below 3.5%. PMID:26950570

  13. Biological enhancement of hydrocarbon extraction

    DOEpatents

    Brigmon, Robin L.; Berry, Christopher J.

    2009-01-06

    A method of microbial enhanced oil recovery for recovering oil from an oil-bearing rock formation is provided. The methodology uses a consortium of bacteria including a mixture of surfactant producing bacteria and non-surfactant enzyme producing bacteria which may release hydrocarbons from bitumen containing sands. The described bioprocess can work with existing petroleum recovery protocols. The consortium microorganisms are also useful for treatment of above oil sands, ground waste tailings, subsurface oil recovery, and similar materials to enhance remediation and/or recovery of additional hydrocarbons from the materials.

  14. DEVELOPMENT AND EVALUATION OF MONITORING METHODS FOR POLYCYCLIC AROMATIC HYDROCARBONS IN HOUSE DUST AND TRACK-IN SOIL

    EPA Science Inventory

    The analytical methods were developed for the determination of PAH and PCBs in the dust and soil based on sonication with hexane and 10% ether/hexane, respectively, and analysis by gas chromatography/mass spectrometry (GC/MS). uantitative recoveries of spiked perdeuterated PAH an...

  15. Calibration study of the CCSD(T)-F12a/b methods for C2 and small hydrocarbons

    NASA Astrophysics Data System (ADS)

    Feller, David; Peterson, Kirk A.; Hill, J. Grant

    2010-11-01

    Explicitly correlated CCSD(T)-F12a/b methods combined with basis sets specifically designed for this technique have been tested for their ability to reproduce standard CCSD(T) benchmark data covering 16 small molecules composed of hydrogen and carbon. The standard method calibration set was obtained with very large one-particle basis sets, including some aug-cc-pV7Z and aug-cc-pV8Z results. Whenever possible, the molecular properties (atomization energies, structures, and harmonic frequencies) were extrapolated to the complete basis set limit in order to facilitate a direct comparison of the standard and explicitly correlated approaches without ambiguities arising from the use of different basis sets. With basis sets of triple-ζ quality or better, the F12a variant was found to overshoot the presumed basis set limit, while the F12b method converged rapidly and uniformly. Extrapolation of F12b energies to the basis set limit was found to be very effective at reproducing the best standard method atomization energies. Even extrapolations based on the small cc-pVDZ-F12/cc-pVTZ-F12 combination proved capable of a mean absolute deviation of 0.20 kcal/mol. The accuracy and simultaneous cost savings of the F12b approach are such that it should enable high quality property calculations to be performed on chemical systems that are too large for standard CCSD(T).

  16. Comparison of two extraction methods for the analysis of petroleum hydrocarbon residues in mallard duck eggs by GC and GC-MS. [NONE

    SciTech Connect

    Belisle, A.A.; Gay, M.L.; Coon, N.C.

    1981-01-01

    Hydrocarbon residues in pooled eggs from a mallard duck on a diet of 25,000 ppm South Louisiana crude oil were compared after cleanup with and without saponification. The saponification procedure yielded superior reproducibility and extraction efficiency..

  17. Comparison of two extraction methods for the analysis of petroleum hydrocarbon residues in mallard duck eggs by GC and GC-MS

    USGS Publications Warehouse

    Belisle, A.A.; Gay, M.L.; Coon, N.C.

    1981-01-01

    Hydrocarbon residues in pooled eggs from a mallard duck on a diet of 25,000 ppm South Louisiana crude oil were compared after cleanup with and without saponification. The saponification procedure yielded superior reproducibility and extraction efficiency

  18. Thermal analysis of thermo-gravimetric measurements of spent nuclear fuel oxidation rates

    SciTech Connect

    Cramer, E.R.

    1997-10-09

    A detailed thermal analysis was completed of the sample temperatures in the Thermo-Gravimetric Analysis (TGA) system used to measure irradiated N Reactor fuel oxidation rates. Sample temperatures during the oxidation process did not show the increase which was postulated as a result of the exothermic reactions. The analysis shows the axial conduction of heat in the sample holder effectively removes the added heat and only a very small, i.e., <10 C, increase in temperature is calculated. A room temperature evaporation test with water showed the sample thermocouple sensitivity to be more than adequate to account for a temperature change of approximately 5 C. Therefore, measured temperatures in the TGA are within approximately 10 C of the actual sample temperatures and no adjustments to reported data to account for the heat input from the oxidation process are necessary.

  19. A micrographic and gravimetric study of intercalation and deintercalation of graphite fibers

    NASA Technical Reports Server (NTRS)

    Hung, C. C.

    1985-01-01

    Intercalation and deintercalation of Union Carbide P-100 graphite fibers with liquid and vaporous bromine was studied gravimetrically and microscopically. The mass of the bromine intercalated fibers was found to be 17 to 20 percent greater than their pristine counterpart. This variation decreased to 17 to 18 percent after heating in air for 3 days at 200 C and to 14.5 to 18 percent after 6 days of 260 C heating. The fiber length did not change throughout the experiment. The fiber diameter increased during intercalation and decreased slightly upon deintercalation but was not affected by heating to 260 C for 3 days in air. Comparing the mass and volume data to those with highly oriented pyrolitic graphite or natural single crystal graphite suggested the possibility that the intercalated P-100 fibers could be mostly stage 4.

  20. Global detailed gravimetric geoid. [based on gravity model derived from satellite tracking and surface gravity data

    NASA Technical Reports Server (NTRS)

    Vincent, S.; Marsh, J. G.

    1973-01-01

    A global detailed gravimetric geoid has been computed by combining the Goddard Space Flight Center GEM-4 gravity model derived from satellite and surface gravity data and surface 1 deg-by-1 deg mean free air gravity anomaly data. The accuracy of the geoid is + or - 2 meters on continents, 5 to 7 meters in areas where surface gravity data are sparse, and 10 to 15 meters in areas where no surface gravity data are available. Comparisons have been made with the astrogeodetic data provided by Rice (United States), Bomford (Europe), and Mather (Australia). Comparisons have also been carried out with geoid heights derived from satellite solutions for geocentric station coordinates in North America, the Caribbean, Europe, and Australia.

  1. Hydrocarbon components in carbonaceous meteorites

    NASA Astrophysics Data System (ADS)

    Kissin, Y. V.

    2003-05-01

    Currently, the presence of free n-alkanes and isoprenoid alkanes in carbonaceous meteorites is usually explained either by microbial contamination during the period between the meteorite fall and collection or by contamination from the environment of analytical laboratories and museums. The goal of this research was to repeat analysis of hydrocarbon components in meteorites and to investigate possible meteorite contamination routes discussed in the literature. Experimental analysis of free organic constituents in five carbonaceous meteorites by infrared spectroscopy (IR) and gas chromatographic (GC) methods confirmed the presence of extractable aliphatic components, n-alkanes in the C 15H 32-C 27H 56 range and isoprenoid alkanes (phytane, pristane, and norpristane), in some of these meteorites. The contents of these compounds vary depending on the source. Insoluble organic components of two meteorites (meteorite kerogens) were isolated, and their composition was analyzed by IR and cracking/GC methods. Comparison with the data on several terrestrial contamination sources proposed in the literature shows that the presence of free saturated hydrocarbons in meteorites and the composition of the meteorite kerogen could not be explained either by microbial contamination or by contamination from the laboratory environment. The types of the hydrocarbons in meteorites resemble those typical of ancient terrestrial deposits of organic-rich sediments, except for the absence of lighter hydrocarbons, which apparently slowly evaporated in space, and multi-ring naphthenic compounds of the biologic origin, steranes, terpanes, etc. The prevailing current explanation for the presence of free linear saturated hydrocarbons in carbonaceous meteorites, apart from contamination, is the abiotic route from hydrogen and carbon monoxide. However, the data on the structure of meteorite kerogens require a search for different routes that initially produce complex polymeric structures containing

  2. Hydration of the dTn.dAn x dTn parallel triple helix: a Fourier transform infrared and gravimetric study correlated with molecular dynamics simulations.

    PubMed Central

    Ouali, M; Gousset, H; Geinguenaud, F; Liquier, J; Gabarro-Arpa, J; Le Bret, M; Taillandier, E

    1997-01-01

    We present a comparative analysis of the water organization around the dTn.dAn x dTn triple helix and the Watson-Crick double helix dTn.dAn respectively by means of gravimetric measurements, infrared spectroscopy and molecular dynamics simulations. The hydration per nucleotide determined by gravimetric and spectroscopic methods correlated with the molecular dynamics simulations shows that at high relative humidity (98% RH) the triple helix is less solvated than the duplex (17 +/- 2 water molecules per nucleotide instead of 21 +/-1). The experimental desorption curves are different for both structures and indicate that below 81% RH the triplex becomes more hydrated than the duplex. At this RH the FTIR spectra show the emergence of N-type sugars in the adenosine strand of the triplex. When the third strand is bound in the major groove of the Watson-Crick duplex molecular dynamics simulations show the formation of a spine of water molecules between the two thymidine strands. PMID:9365262

  3. The use of gravimetric data from GRACE mission in the understanding of polar motion variations

    NASA Astrophysics Data System (ADS)

    Seoane, L.; Nastula, J.; Bizouard, C.; Gambis, D.

    2009-08-01

    Tesseral coefficients C21 and S21 derived from Gravity Recovery and Climate Experiment (GRACE) observations allow to compute the mass term of the polar-motion excitation function. This independent estimation can improve the geophysical models and, in addition, determine the unmodelled phenomena. In this paper, we intend to validate the polar motion excitation derived from GRACE's last release (GRACE Release 4) computed by different institutes: GeoForschungsZentrum (GFZ), Postdam, Germany; Center for Space Research (CSR), Austin, USA; Jet Propulsion Laboratory (JPL), Pasadena, USA, and the Groupe de Recherche en Géodésie Spatiale (GRGS), Toulouse, France. For this purpose, we compare these excitations functions first to the mass term obtained from observed Earth's rotation variations free of the motion term and, second, to the mass term estimated from geophysical fluids models. We confirm the large improvement of the CSR solution, and we show that the GRGS estimate is also well correlated with the geodetic observations. Significant discrepancies exist between the solutions of each centre. The source of these differences is probably related to the data processing strategy. We also consider residuals computed after removing the geophysical models or the gravimetric solutions from the geodetic mass term. We show that the residual excitation based on models is smoother than the gravimetric data, which are still noisy. Still, they are comparable for the χ2 component. It appears that χ2 residual signals using GFZ and JPL data have less variability. Finally, for assessing the impact of the geophysical fluids models choice on our results, we checked two different oceanic excitation series. We show the significant differences in the residuals correlations, especially for the χ1 more sensitive to the oceanic signals.

  4. Isolation and Characterization of Hydrocarbon-Degrading Yeast Strains from Petroleum Contaminated Industrial Wastewater.

    PubMed

    Gargouri, Boutheina; Mhiri, Najla; Karray, Fatma; Aloui, Fathi; Sayadi, Sami

    2015-01-01

    Two yeast strains are enriched and isolated from industrial refinery wastewater. These strains were observed for their ability to utilize several classes of petroleum hydrocarbons substrates, such as n-alkanes and aromatic hydrocarbons as a sole carbon source. Phylogenetic analysis based on the D1/D2 variable domain and the ITS-region sequences indicated that strains HC1 and HC4 were members of the genera Candida and Trichosporon, respectively. The mechanism of hydrocarbon uptaking by yeast, Candida, and Trichosporon has been studied by means of the kinetic analysis of hydrocarbons-degrading yeasts growth and substrate assimilation. Biodegradation capacity and biomass quantity were daily measured during twelve days by gravimetric analysis and gas chromatography coupled with mass spectrometry techniques. Removal of n-alkanes indicated a strong ability of hydrocarbon biodegradation by the isolated yeast strains. These two strains grew on long-chain n-alkane, diesel oil, and crude oil but failed to grow on short-chain n-alkane and aromatic hydrocarbons. Growth measurement attributes of the isolates, using n-hexadecane, diesel oil, and crude oil as substrates, showed that strain HC1 had better degradation for hydrocarbon substrates than strain HC4. In conclusion, these yeast strains can be useful for the bioremediation process and decreasing petroleum pollution in wastewater contaminated with petroleum hydrocarbons. PMID:26339653

  5. Isolation and Characterization of Hydrocarbon-Degrading Yeast Strains from Petroleum Contaminated Industrial Wastewater

    PubMed Central

    Gargouri, Boutheina; Mhiri, Najla; Karray, Fatma; Aloui, Fathi; Sayadi, Sami

    2015-01-01

    Two yeast strains are enriched and isolated from industrial refinery wastewater. These strains were observed for their ability to utilize several classes of petroleum hydrocarbons substrates, such as n-alkanes and aromatic hydrocarbons as a sole carbon source. Phylogenetic analysis based on the D1/D2 variable domain and the ITS-region sequences indicated that strains HC1 and HC4 were members of the genera Candida and Trichosporon, respectively. The mechanism of hydrocarbon uptaking by yeast, Candida, and Trichosporon has been studied by means of the kinetic analysis of hydrocarbons-degrading yeasts growth and substrate assimilation. Biodegradation capacity and biomass quantity were daily measured during twelve days by gravimetric analysis and gas chromatography coupled with mass spectrometry techniques. Removal of n-alkanes indicated a strong ability of hydrocarbon biodegradation by the isolated yeast strains. These two strains grew on long-chain n-alkane, diesel oil, and crude oil but failed to grow on short-chain n-alkane and aromatic hydrocarbons. Growth measurement attributes of the isolates, using n-hexadecane, diesel oil, and crude oil as substrates, showed that strain HC1 had better degradation for hydrocarbon substrates than strain HC4. In conclusion, these yeast strains can be useful for the bioremediation process and decreasing petroleum pollution in wastewater contaminated with petroleum hydrocarbons. PMID:26339653

  6. Development of new method of δ(13)C measurement for trace hydrocarbons in natural gas using solid phase micro-extraction coupled to gas chromatography isotope ratio mass spectrometry.

    PubMed

    Li, Zhongping; Wang, Xibin; Li, Liwu; Zhang, Mingjie; Tao, Mingxin; Xing, Lantian; Cao, Chunhui; Xia, Yanqing

    2014-11-01

    Compound specific isotope analysis (CSIA) of normal-level hydrocarbons (C1-C4) in natural gas is often successfully used in natural gas origin identification and classification, but little progress so far has been made for trace level hydrocarbons (C5-C14) in natural gas. In this study, we developed a method for rapid analysis of carbon isotopic ratios for trace hydrocarbons in natural gas samples. This method can be described as a combined approach characterized by solid phase micro-extraction (SPME) technique coupled to gas chromatography isotope ratio mass spectrometry (GC/IRMS). In this study, the CAR-PDMS fiber was chosen as the SPME adsorptive material after comparative experiments with other four fibers, and the parameters, including equilibration time, extraction temperature and desorption time, for efficient extraction of trace hydrocarbons were systematically optimized. The results showed the carbon isotopic fractionation was not observed as a function of equilibration time and extraction temperature. And the δ(13)C signatures determined by SPME-GC/IRMS were in good agreement with the known δ(13)C values of C5-C14 measured by GC-IRMS, and the accuracy is generally within ±0.5‰. Five natural gas samples were analyzed using this method, and the δ(13)C values for C5-C14 components were obtained with satisfied repeatability. The SPME-GC/IRMS approach fitted with CAR-PDMS fiber is well suited for the preconcentration of trace hydrocarbons and provides so far the most reliable carbon isotopic analysis for trace compounds in natural gas. PMID:25465020

  7. Machine method and apparatus for determining the presence and location of hydrocarbon deposits within a subsurface earth formation

    SciTech Connect

    Gaymard, R.G.; Poupon, A.

    1983-01-18

    In accordance with illustrative embodiments of the present invention, methods for processing well logging data comprise deriving measurements of a plurality of earth formation parameters and combining these measurements in a new manner to enable interpretation of shales and shaly sand type formations. More particularly, measurements of a plurality of the hydrogen index, bulk density, radially deep and shallow resistivity, spontaneous potential, acoustic travel time and natural formation radioactivity content are made and combined in a manner to produce data useful in evaluating shales and shaly sand type formations.

  8. Development of laser-based molecular spectrometric methods for polycyclic aromatic hydrocarbons in environmental sciences. Progress report, September 1, 1981-April 1, 1984

    SciTech Connect

    Winefordner, J.D.

    1984-01-01

    The proposal research consists of six projects dealing with laser excitation of molecules as analytical approaches to trace analysis of polycyclic aromatic hydrocarbons (PAHs). Laser photoionization of PAHs in a special liquid cell will be detected by the optical impedance approach in which the charge in conductance and dielectric constant produces a change in the impedance of the median in a coil or a capacitor. Liquid samples containing PAHs from HPLCs will be nebulized to produce aerosols or naturally occurring aerosols will be studied by the combined approach of dye laser excited fluorescence, photoacoustic and photoionization approaches. Laser induced fluorescence of gas chromatographic elements will be developed. A supersonic beam will be used to rotationally cool thermally vaporized PAHs in complex samples and an intense xenon arc source will be compared with a pulsed or CW dye laser as excitation sources for fluorescence. Pulsed photothermal radiometry will be used to study PAHs collected on filter paper and other substrates. Air particulate fingerprinting will be investigated by collecting air particulates in graphite discs, exciting with a dye laser through a microscope, and measurement of the fluorescence spectra. This approach will be compared with the flow cytometer approach. Double modulation will be used to maximize the fluorescence signal-to-background scatter. Surface enhanced Raman and luminescence spectrometry of PAHs on filter paper will be evaluated as a selective, sensitive, analytical method.

  9. Simplified and rapid determination of polychlorinated biphenyls, polybrominated diphenyl ethers, and polycyclic aromatic hydrocarbons in fish and shrimps integrated into a single method.

    PubMed

    Kalachova, Kamila; Pulkrabova, Jana; Drabova, Lucie; Cajka, Tomas; Kocourek, Vladimir; Hajslova, Jana

    2011-11-30

    In this study, a new rapid and flexible method for the simultaneous determination of 18 key representatives of polychlorinated biphenyls (PCBs), 7 polybrominated diphenyl ethers (PBDEs), and 32 polycyclic aromatic hydrocarbons (PAHs) in fish and shrimps by gas chromatography coupled to mass spectrometry (GC-MS) was developed and validated. A substantial simplification of sample processing prior to quantification step was achieved: after addition of water to homogenized sample, transfer of hydrophobic analytes into ethyl acetate was supported by added inorganic salts. Bulk fat, contained in crude organic extract obtained by partition, was subsequently removed on a silica minicolumn. This approach enabled to process six samples in less than 1h; moreover, the volume of an extraction solvent and consumption of other chemicals can be significantly reduced compared to, e.g., traditional Soxhlet extraction followed by gel permeation chromatography. The recoveries of target analytes were in the range of 73-120% even at the lowest spiking level (1 μg kg(-1)), repeatabilities (relative standard deviations, RSDs) ranged from 1 to 20%. Under optimized GC-MS conditions (time-of-flight mass analyzer, TOF), the limits of quantification (LOQs) were as follows: PCBs 0.1-0.5 μg kg(-1), PBDEs 0.5 μg kg(-1), and PAHs 0.05-0.25 μg kg(-1). Ambient mass spectrometry employing a direct analysis in real time (DART) ion source was shown as an effective tool for fat control in extract, which is needed during the method development and examination of unknown samples prior to the analysis. Further extension of a method scope by other similar analytes is easily possible. PMID:22027123

  10. Analysis of polycyclic aromatic hydrocarbons in fish: evaluation of a quick, easy, cheap, effective, rugged, and safe extraction method.

    PubMed

    Ramalhosa, Maria João; Paíga, Paula; Morais, Simone; Delerue-Matos, Cristina; Oliveira, Maria Beatriz Prior Pinto

    2009-10-01

    QuEChERS method was evaluated for extraction of 16 PAHs from fish samples. For a selective measurement of the compounds, extracts were analysed by LC with fluorescence detection. The overall analytical procedure was validated by systematic recovery experiments at three levels and by using the standard reference material SRM 2977 (mussel tissue). The targeted contaminants, except naphthalene and acenaphthene, were successfully extracted from SRM 2977 with recoveries ranging from 63.5-110.0% with variation coefficients not exceeding 8%. The optimum QuEChERS conditions were the following: 5 g of homogenised fish sample, 10 mL of ACN, agitation performed by vortex during 3 min. Quantification limits ranging from 0.12-1.90 ng/g wet weight (0.30-4.70 microg/L) were obtained. The optimized methodology was applied to assess the safety concerning PAHs contents of horse mackerel (Trachurus trachurus), chub mackerel (Scomber japonicus), sardine (Sardina pilchardus) and farmed seabass (Dicentrarchus labrax). Although benzo(a)pyrene, the marker used for evaluating the carcinogenic risk of PAHs in food, was not detected in the analysed samples (89 individuals corresponding to 27 homogenized samples), the overall mean concentration ranged from 2.52 +/- 1.20 ng/g in horse mackerel to 14.6 +/- 2.8 ng/g in farmed seabass. Significant differences were found between the mean PAHs concentrations of the four groups. PMID:19750509

  11. Hydrocarbon distribution in the Maracaibo Basin

    SciTech Connect

    Scherer, W.

    1996-08-01

    The prolific Maracaibo basin contains the second largest hydrocarbon accumulation in South America; it has been one of the principal oil producers of the world since the beginning of this century. Exploratory efforts in this basin, carried out with new techniques and new ideas, continue today, so it is of interest to determine the trends of hydrocarbon concentrations in terms of resources per unit volume of sediments and to correlate them to stratigraphic, sedimentary-tectonic and geochemical variables. Regional scale maps representing the 24 principal geologic and geochemical variables that are thought to be a function of hydrocarbon generation, migration and accumulation were discretized on a 25 x 25 km grid. Variables used are isopach and Total Organic Carbon (TOC) of source rocks, isopach, sandstone content and grain size parameters of reservoir rocks, isopach of stratigraphic seal and overburden, maximum paleotemperatures (R{sub o} and T{sub max}), tectonic energy (fault length and displacement) and hydrocarbon families. Multivariate analytical statistics was used to obtain the trends of hydrocarbon distributions. The resulting hydrocarbon concentration trend map was quantitatively correlated to known hydrocarbon accumulations and prospective areas, where additional new accumulations might be found, were obtained. It can be shown that the largest known hydrocarbon concentrations correspond to areas of greatest cumulative overburden. The southern Zulia Catatumbo region is the largest prospective area determined by this method.

  12. Using supercritical fluids to refine hydrocarbons

    DOEpatents

    Yarbro, Stephen Lee

    2015-06-09

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

  13. Single-laboratory validation of a GC/MS method for the determination of 27 polycyclic aromatic hydrocarbons (PAHs) in oils and fats.

    PubMed

    Rose, M; White, S; Macarthur, R; Petch, R G; Holland, J; Damant, A P

    2007-06-01

    A protocol for the measurement of 27 polycyclic aromatic hydrocarbons (PAHs) in vegetable oils by GC/MS has undergone single-laboratory validation. PAHs were measured in three oils (olive pomace, sunflower and coconut oil). Five samples of each oil (one unfortified, and four fortified at concentrations between 2 and 50 microg kg(-1)) were analysed in replicate (four times in separate runs). Two samples (one unfortified and one fortified at 2 microg kg(-1)) of five oils (virgin olive oil, grapeseed oil, toasted sesame oil, olive margarine and palm oil) were also analysed. The validation included an assessment of measurement bias from the results of 120 measurements of a certified reference material (coconut oil BCR CRM458 certified for six PAHs). The method is capable of reliably detecting 26 out of 27 PAHs, at concentration <2 microg kg(-1) which is the European Union maximum limit for benzo[a]pyrene, in vegetable oils, olive pomace oil, sunflower oil and coconut oil. Quantitative results were obtained that are fit for purpose for concentrations from <2 to 50 microg kg(-1) for 24 out of 27 PAHs in olive pomace oil, sunflower oil and coconut oil. The reliable detection of 2 microg kg(-1) of PAHs in five additional oils (virgin olive oil, grapeseed oil, toasted sesame oil, olive margarine and palm oil) has been demonstrated. The method failed to produce fit-for-purpose results for the measurement of dibenzo[a,h]pyrene, anthanthrene and cyclopenta[c,d]pyrene. The reason for the failure was the large variation in results. The likely cause was the lack of availability of (13)C isotope internal standards for these PAHs at the time of the study. The protocol has been shown to be fit-for-purpose and is suitable for formal validation by inter-laboratory collaborative study. PMID:17487605

  14. Significant variation in the concentration of carcinogenic polycyclic aromatic hydrocarbons in yerba maté samples by brand, batch and processing method

    PubMed Central

    Golozar, Asieh; Fagundes, Renato B.; Etemadi, Arash; Schantz, Michele M.; Kamangar, Farin; Abnet, Christian C.; Dawsey, Sanford M.

    2012-01-01

    Drinking maté, common in southern South America, may increase the risk of esophageal squamous cell carcinoma (ESCC). In 2006, we found high but variable polycyclic aromatic hydrocarbon (PAH) content in commercial yerba maté samples from eight Brazilian brands. The PAH content of new samples from the same brands, purchased in 2008, and four brands from a single manufacturer processed in different ways, obtained in 2010, were quantified to determine whether PAH concentration was still high, PAH content variation was brand specific, and whether processing method affects PAH content of commercial yerba maté. Concentrations of individual PAHs were quantified using gas chromatography/mass spectrometry with deuterated PAHs as internal standards. Median total PAH concentration was 1500 ng/g (range: 625 to 3710 ng/g) and 1090 ng/g (621 to 1990 ng/g) in 2008 and 2010 samples, respectively. Comparing 2006 and 2008 samples, some brands had high PAH concentrations in both years, while PAH concentration changed considerably in others. Benzo[a]pyrene concentrations ranged from 11.9 to 99.3 ng/g and 5.11 to 21.0 ng/g in 2008 and 2010 samples, respectively. The 2010 sample processed without touching smoke had the lowest benzo[a]pyrene content. These results support previous findings of very high total and carcinogenic PAH concentrations in yerba maté, perhaps contributing to the high incidence of ESCC in southern South America. The large PAH content variation by brand, batch and processing method suggests it may be possible to reduce the content of carcinogenic PAHs in commercial yerba maté, making it a healthier beverage. PMID:23101992

  15. Investigating the Quantitative Structure-Activity Relationships for Antibody Recognition of Two Immunoassays for Polycyclic Aromatic Hydrocarbons by Multiple Regression Methods

    PubMed Central

    Zhang, Yan-Feng; Zhang, Li; Gao, Zhi-Xian; Dai, Shu-Gui

    2012-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants found in the environment. Immunoassays represent useful analytical methods to complement traditional analytical procedures for PAHs. Cross-reactivity (CR) is a very useful character to evaluate the extent of cross-reaction of a cross-reactant in immunoreactions and immunoassays. The quantitative relationships between the molecular properties and the CR of PAHs were established by stepwise multiple linear regression, principal component regression and partial least square regression, using the data of two commercial enzyme-linked immunosorbent assay (ELISA) kits. The objective is to find the most important molecular properties that affect the CR, and predict the CR by multiple regression methods. The results show that the physicochemical, electronic and topological properties of the PAH molecules have an integrated effect on the CR properties for the two ELISAs, among which molar solubility (Sm) and valence molecular connectivity index (3χv) are the most important factors. The obtained regression equations for RisC kit are all statistically significant (p < 0.005) and show satisfactory ability for predicting CR values, while equations for RaPID kit are all not significant (p > 0.05) and not suitable for predicting. It is probably because that the RisC immunoassay employs a monoclonal antibody, while the RaPID kit is based on polyclonal antibody. Considering the important effect of solubility on the CR values, cross-reaction potential (CRP) is calculated and used as a complement of CR for evaluation of cross-reactions in immunoassays. Only the compounds with both high CR and high CRP can cause intense cross-reactions in immunoassays. PMID:23012547

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

    DOEpatents

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

    2016-09-06

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

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

    DOEpatents

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

    2016-03-08

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

  18. Deep desulfurization of hydrocarbon fuels

    DOEpatents

    Song, Chunshan; Ma, Xiaoliang; Sprague, Michael J.; Subramani, Velu

    2012-04-17

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

  19. [Determination of polycyclic aromatic hydrocarbons in the working environment during aluminum production].

    PubMed

    Brzeźnicki, S; Przybylski, H

    1996-01-01

    Polycyclic aromatic hydrocarbons (PAHs) belong to a group od chemicals responsible, to a great extent, for the contamination of the industrial and ambient air. A number of industrial processes such as coke production, coal tar processing, production of electric energy and certain rubber goods as well as metallurgy, especially aluminium metallurgy with its anodes made of coal tar pitch are the major sources of PAH emission. An attempt was made to determine PAH concentrations at selected workposts at an aluminium production plant. Breathing zone air samples were collected by individual dosimetry. Coal tar pitch volatiles were determined by a gravimetric method and individual PAHs by HPLC. The presence of naphtalene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, triphenylene, benzo/a/anthracene, chrysene, benzo/a/pyrene, benzo/b/fluorenthene, benzo/k/fluoranthene, benzo/a/pyrene, dibenzo/a,h/anthracene, benzo/g,h,i/perylene and indeno/1,2,3-c,d/pyrene was identified at all investigated workposts. The highest concentrations of benzo/a/pyrene and coal tar pitch volatiles were found at workposts of crane operators which is due to the character of the work performed. The replacement of "wet" anode material by the "dry" one should contribute to improving of the working conditions. PMID:8834591

  20. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory : determination of polycyclic aromatic hydrocarbon compounds in sediment by gas chromatography/mass spectrometry

    USGS Publications Warehouse

    Olson, Mary C.; Iverson, Jana L.; Furlong, Edward T.; Schroeder, Michael P.

    2004-01-01

    A method for the determination of 28 polycyclic aromatic hydrocarbons (PAHs) and 25 alkylated PAH homolog groups in sediment samples is described. The compounds are extracted from sediment by solvent extraction, followed by partial isolation using high-performance gel permeation chromatography. The compounds are identified and uantitated using capillary-column gas chromatography/mass spectrometry. The report presents performance data for full-scan ion monitoring. Method detection limits in laboratory reagent matrix samples range from 1.3 to 5.1 micrograms per kilogram for the 28 PAHs. The 25 groups of alkylated PAHs are homologs of five groups of isomeric parent PAHs. Because of the lack of authentic standards, these homologs are reported semiquantitatively using a response factor from a parent PAH or a specific alkylated PAH. Precision data for the alkylated PAH homologs are presented using two different standard reference manuals produced by the National Institute of Standards and Technology: SRM 1941b and SRM 1944. The percent relative standard deviations for identified alkylated PAH homolog groups ranged from 1.55 to 6.98 for SRM 1941b and from 6.11 to 12.0 for SRM 1944. Homolog group concentrations reported under this method include the concentrations of individually identified compounds that are members of the group. Organochlorine (OC) pesticides--including toxaphene, polychlorinated biphenyls (PCBs), and organophosphate (OP) pesticides--can be isolated simultaneously using this method. In brief, sediment samples are centrifuged to remove excess water and extracted overnight with dichloromethan (95 percent) and methanol (5 percent). The extract is concentrated and then filtered through a 0.2-micrometer polytetrafluoroethylene syringe filter. The PAH fraction is isolated by quantitatively injecting an aliquot of sample onto two polystyrene-divinylbenzene gel-permeation chromatographic columns connected in series. The compounds are eluted with dichloromethane

  1. A chemical extraction method for mimicking bioavailability of polycyclic aromatic hydrocarbons to wheat grown in soils containing various amounts of organic matter

    SciTech Connect

    Shu Tao; Fuliu Xu; Wenxin Liu; Yanhong Cui; Raymond M. Coveney, Jr.

    2006-04-01

    Severe contamination of agricultural soils by polycyclic aromatic hydrocarbons (PAHs) occurs in many places in China mainly as a result of coal and biomass combustion. Because ingestion is the main source of human exposure to PAHs and vegetables are basic ingredients for the Chinese diet, it is important to know how and to what extent PAHs are accumulated in vegetables produced in contaminated soils. This study, evaluated the extent to which organic matter contents in soils influence the accumulation of PAHs by the roots of wheat plants and have developed a rapid chemical method for determining the bioavailability of PAH. Four PAHs, naphthalene, acenaphthylene, fluorene, and phenanthrene, were added to natural soil samples with different amounts of organic matter for pot experiments to evaluate apparent bioavailability of PAHs to wheat roots (Triticum aestivum L.). The extractabilities of PAHs in the soil were tested by a sequential extraction scheme using accelerated solvent extraction with water, n-hexane, and a mixture of dichloromethane and acetone as solvents. The water or n-hexane-extractable PAHs were positively correlated to dissolved organic matter (DOM) and negatively correlated to total organic matter (TOM), indicating mobilization and immobilization effects of DOM and TOM on soil PAHs, respectively. The apparent accumulation of PAHs by wheat roots was also positively and negatively correlated to DOM and TOM, respectively. As a result, there are positive correlations between the amounts of PAHs extracted by water or n-hexane and the quantities accumulated in plant roots, suggesting the feasibility of using water- or n-hexanes-extractable fractions as indicators of PAH availability to plants. 19 refs., 8 figs., 1 tab.

  2. Emulsification liquid-liquid microextraction based on deep eutectic solvent: An extraction method for the determination of benzene, toluene, ethylbenzene and seven polycyclic aromatic hydrocarbons from water samples.

    PubMed

    Khezeli, Tahere; Daneshfar, Ali; Sahraei, Reza

    2015-12-18

    In this study, for the first time, a simple, inexpensive and sensitive method named emulsification liquid-liquid microextraction based on deep eutectic solvent (ELLME-DES) was used for the extraction of benzene, toluene, ethylbenzene (BTE) and seven polycyclic aromatic hydrocarbons (PAHs) from water samples. In a typical experiment, 100μL of DES (as water-miscible extraction solvent) was added to 1.5mL of sample solution containing target analytes. A homogeneous solution was formed immediately. Injection of 100μL of THF (as emulsifier agent) into homogeneous solution provided a turbid state. After extraction, phase separation (aqueous phase/DES rich phase) was performed by centrifugation. DES rich phase was withdrawn by a micro-syringe and submitted to isocratic reverse-phase HPLC with UV detection. Under optimum conditions obtained by response surface methodology (RSM) and desirability function (DF), the calibration graphs were linear in the concentration range from 10 to 200μg/L for benzene, 10-400μg/L for toluene, 1-400μg/L for ethylbenzene, biphenyl, chrysene and fluorene, and 0.1-400μg/L for anthracene, benzo[a]pyrene, phenanthrene and pyrene. The coefficients of determination (r(2)) and limits of detection were 0.9924-0.9997 and 0.02-6.8μg/L, respectively. This procedure was successfully applied to the determination of target analytes in spiked water samples. The relative mean recoveries ranged from 93.1 to 103.3%. PMID:26614169

  3. Polyaniline nanofiber sponge filled graphene foam as high gravimetric and volumetric capacitance electrode

    NASA Astrophysics Data System (ADS)

    Pedrós, J.; Boscá, A.; Martínez, J.; Ruiz-Gómez, S.; Pérez, L.; Barranco, V.; Calle, F.

    2016-06-01

    A 3D hierarchical porous composite structure is developed via the controlled electrodeposition of a polyaniline nanofiber sponge (PANI-NFS) that fills the pores of a chemical vapor deposited graphene foam (GF). The PANI-NFS/GF composite combines the efficient electronic transport in the GF scaffold (with 100-500 μm pore size) with the rapid diffusion of the electrolyte ions into the high-specific-surface-area and densely-packed PANI-NFS (with 100-500 nm pore size). The factor of 1000 in the pore hierarchy and the synergy between the materials, that form a supercapacitor composite electrode with an integrated extended current collector, lead to both very high gravimetric and volumetric capacitances. In particular, values of 1474 F g-1 and 86 F cm-3 for a GF filling factor of 11% (leading to an estimated value of 782 F cm-3 for 100%), respectively, are obtained at a current density of 0.47 A g-1. Moreover, the composite electrode presents a capacitance retention of 83% after 15000 cycles. This excellent behavior makes the PANI-NFS/GF composite electrodes very attractive for high-performance supercapacitors.

  4. Gravimetric mass balance products for the Antarctic and Greenland ice sheet

    NASA Astrophysics Data System (ADS)

    Horwath, Martin; Groh, Andreas; Horvath, Alexander; Forsberg, Rene; Meister, Rakia; Shepherd, Andrew; Hogg, Anna; Muir, Alan

    2016-04-01

    Within the framework of ESA's Climate Change Initiative (CCI) mass balance products for both the Antarctic Ice Sheet (AIS) and the Greenland Ice Sheet (GIS) have been developed by the AIS_cci and the GIS_cci project. These Gravimetric Mass Balance (GMB) products are derived from satellite gravimetry data acquired by GRACE (Gravity Recovery and Climate Experiment), which is the only sensor directly sensitive to changes in mass. Using monthly GRACE gravity field solutions covering the period from 2002 until present two different GMB products are derived: (a) time series of monthly mass changes for the entire ice sheet and for individual drainage basins, and (b) gridded mass changes covering the entire ice sheet. The gridded product depicts spatial patterns of mass changes at a formal resolution of about 50 km, although the effective resolution provided by GRACE is about 200-500km. The algorithms used for the product generation have been selected within an open round robin experiment and are optimized to account for the complex GRACE error structures, to advance the limited spatial resolution and to separate signals super-imposed to mass changes of the cryosphere. Here the first release of the ESA CCI GMB products is presented. Both the basin averaged and the gridded products are assessed regarding their signal content and error characteristics. Finally, up-to-date mass balance estimates are presented for both ice sheets. The GMB products are freely accessible through data portals hosted by the AIS_cci and the GIS_cci project.

  5. An instrument for gravimetric calibration of flow devices with corrosive gases

    NASA Astrophysics Data System (ADS)

    Remenyik, Carl J.; Hylton, James O.

    An instrument was developed for the calibration of mass flow controllers primarily used in the production of semiconductor wafers. Almost all other types of such calibrators require measurement of temperature, pressure, and volume. This instrument measures the weight of gas collected in a container and makes measuring those thermodynamic variables unnecessary. The need to measure the weight of the gas container is eliminated by submerging it in a liquid (presently water) and balancing its weight with the force of buoyancy. The accuracy of this gravimetric calibrator is unaffected by the pressure and temperature of the gas. The calibrator can also measure reactive, corrosive, and nonideal gases. The container remains connected to the process by a torsion capillary, and a load cell measures the changing gas weight continuously throughout the measuring process. A prototype was designed for gas flows ranging from 1 sccm of hydrogen to 10,000 sccm of tungsten hexafluoride, constructed, tested, and used to calibrate flow devices. Experience with the prototype and results are presented, and plans for further developments are discussed. Design of a version for the flow range from 0.1 sccm to 100 sccm is in progress.

  6. Evaluation of kinetic parameters for water soluble crystals by thermo gravimetric analysis

    NASA Astrophysics Data System (ADS)

    Rama, S.; Surendra Dilip, C.; Perumal, Rajesh Narayana

    2015-01-01

    This work elevates the relevance of kinetic parameters of nucleation and thermal decomposition for water soluble crystals. The positive soluble Potassium Dihydrogen Phosphate (KDP) and negative soluble Lithium Sulfate Monohydrate (LSMH) materials were chosen for the kinetic evaluation. The results obtained from the classical nucleation theory are verified with the kinetic parameters which are evaluated from thermo gravimetric analysis. Nucleation parameters of a crystallization process such as interfacial energy (σ), volume free energy (ΔGv), critical energy barrier for nucleation (ΔG*), radius of the critical nucleus (r*) and nucleation rate (J) of the positive (KDP) and negative solubility (LSMH) crystals are determined from the classical nucleation theory of solubility-enthalpy relation. The kinetic parameters viz. the order of reaction, enthalpy, Gibbs free energy of activation, frequency factor, and entropy of activation are obtained from the TG based models viz. Horowitz-Metzger, Coats-Redfern and Piloyan-Novikova. The effect of varying temperature with relative variation on Gibbs free energy for both positive and negative solubility crystals is also discussed. The developed model holds good for both positive and negative solubility crystals.

  7. CORONA-INDUCED PHOTOXIDATION OF ALCOHOLS AND HYDROCARBONS OVER TIO2 IN THE ABSENCE OF A UV LIGHT SOURCE - A NOVEL AND ENVIRONMENTALLY FRIENDLY METHOD FOR OXIDATION

    EPA Science Inventory

    Corona-induced photooxidation is a novel oxidation methodology for the efficient oxidation of alcohols and hydrocarbons utilizing the advantage of both the high oxidizing power of ozone formed in the reactor as well as the photooxidation capability of the UV light generated durin...

  8. Recovering hydrocarbons from hydrocarbon-containing vapors

    DOEpatents

    Mirza, Zia I.; Knell, Everett W.; Winter, Bruce L.

    1980-09-30

    Values are recovered from a hydrocarbon-containing vapor by contacting the vapor with quench liquid consisting essentially of hydrocarbons to form a condensate and a vapor residue, the condensate and quench fluid forming a combined liquid stream. The combined liquid stream is mixed with a viscosity-lowering liquid to form a mixed liquid having a viscosity lower than the viscosity of the combined liquid stream to permit easy handling of the combined liquid stream. The quench liquid is a cooled portion of the mixed liquid. Viscosity-lowering liquid is separated from a portion of the mixed liquid and cycled to form additional mixed liquid.

  9. Oxygenated Derivatives of Hydrocarbons

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  10. Hydrocarbon Spectral Database

    National Institute of Standards and Technology Data Gateway

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

  11. Determination of the parameters of binding between lipopolysaccharide and chitosan and its N-acetylated derivative using a gravimetric piezoquartz biosensor.

    PubMed

    Naberezhnykh, G A; Gorbach, V I; Kalmykova, E N; Solov'eva, T F

    2015-03-01

    The interaction of endotoxin (lipopolysaccharide - LPS) with low molecular weight chitosan (5.5 kDa), its N-acylated derivative and chitoliposomes was studied using a gravimetric piezoelectric quartz crystal microbalance biosensor. The optimal conditions for the formation of a biolayer based on immobilized LPS on the resonator surface and its regeneration were elaborated. The association and dissociation rate constants for LPS binding to chitosans were determined and the affinity constants (Kaf) were calculated based on the data on changes in the oscillation frequency of the quartz crystal resonator. The Kaf values correlated with the ones obtained using other methods. The affinity of N-acylated chitosan binding to LPS was higher than that of the parent chitosan binding to LPS. Based on the results obtained, we suggest that water-soluble N-acylated derivatives of chitosan with low degree of substitution of amino groups could be useful compounds for endotoxin binding and neutralization. PMID:25637889

  12. Study of the relative response factors of various gas chromatograph-flame ionisation detector systems for measurement of C2-C9 hydrocarbons in air.

    PubMed

    Slemr, J; Slemr, F; D'Souza, H; Partridge, R

    2004-12-17

    The assumption of an instrument response that is linear with carbon number is frequently used to quantify atmospheric non-methane hydrocarbons (NMHCs) when using gas chromatography (GC) and detection by flame ionisation detector (FID). In order to assess the validity of this widely used method the results of intercomparison measurements by 14 laboratories across Europe were evaluated. The intercomparison measurements were made on synthetic, gravimetrically-prepared, gas mixtures containing 30 hydrocarbons (C2-C9) in the low ppbv range, using various different GC-FID systems. The response per carbon atom of GC-FID systems to individual NMHCs, relative to that of butane, were found to differ by more than 25% across different systems. The differences were mostly caused by analytical errors within particular GC-FID systems and to a more minor degree by systematic deviations related to the molecular structure. (Correction factors due to the molecular structure would lessen the differences, e.g. by about 5% for olefin compounds.) The differences were larger than 10% even after elimination of obvious outliers. Thus, calibration of GC-FID systems with multicomponent NMHC mixtures is found to be essential whenever the accuracy of NMHC measurements is required to be better than about 10%. If calibration by multicomponent gas mixtures is not possible and effective carbon atom response factors are used to quantify the individual NMHC compounds then the particular analytical system should be carefully characterised and its responses to individual compounds be verified. PMID:15633746

  13. Identification of chemistry-dependent artifacts on gravimetric PM fine readings at the T1 site during the MILAGRO field campaign

    NASA Astrophysics Data System (ADS)

    Moya, M.; Madronich, S.; Retama, A.; Weber, R.; Baumann, K.; Nenes, A.; Castillejos, M.; Ponce de León, C.

    2011-01-01

    As part of the MIRAGE (MILAGRO) study conducted 7-30 March 2006 in Mexico City and its Metropolitan Area (MCMA), fine particulate matter (PM 2.5) was collected using two Tapered Element Oscillating Microbalance (TEOM) systems, and a Partisol instrument at the T1 super-site (Tecamac, State of Mexico). Inorganic analysis was performed on filter-based (PM 1, PM 2.5-URG) measurements also collected at this site. Measurements from the gravimetric (TEOMs, Partisol) and URG systems were inter-compared with chemical speciation measurements using a Particle Into Liquid Sampler (PILS) and Thermal Optical methods. Mass and chemical balances applied over the first part of the study (11-22 March) showed that a TEOM using a device (SES) which reduces particle-bound water and retains a fraction of semi-volatile compounds (SVM) gives readings ˜30% larger than a conventional TEOM. In the second part of the study (26-30 March), the loss of SVM during TEOM-heated filter collection (both systems) represented a significant fraction of PM 2.5 mass due to changes in particle composition. Overall, when nonvolatile nitrate dominated (i.e., when associated with crustal species and not NH 4+) and/or sulfate dominates (SO 42-/NO 3- molar ratio is >1), PM 2.5 mass readings are in agreement with those reported for the T1 site if TEOM is using a SES device. However, when volatile nitrate dominates (i.e., NH 4NO 3) or SO 42-/NO 3- molar ratio is <1, a larger fraction is lost from both TEOMs (with or without the SES device). Under the latter regime, uncertainties are large and gravimetric losses may reach 30%-50%. The gravimetric PARTISOL instrument recorded lower readings under all of the aforementioned conditions with differences versus TEOMs decreasing with increasing RH. These findings call for a careful characterization of such volatilization biases to improve current PM (PM 10, PM 2.5) measurements/networks, especially in alkaline-rich environments that can favor such biases. With regards

  14. Method for inverting reflection trace data from 3-D and 4-D seismic surveys and identifying subsurface fluid and pathways in and among hydrocarbon reservoirs based on impedance models

    DOEpatents

    He, W.; Anderson, R.N.

    1998-08-25

    A method is disclosed for inverting 3-D seismic reflection data obtained from seismic surveys to derive impedance models for a subsurface region, and for inversion of multiple 3-D seismic surveys (i.e., 4-D seismic surveys) of the same subsurface volume, separated in time to allow for dynamic fluid migration, such that small scale structure and regions of fluid and dynamic fluid flow within the subsurface volume being studied can be identified. The method allows for the mapping and quantification of available hydrocarbons within a reservoir and is thus useful for hydrocarbon prospecting and reservoir management. An iterative seismic inversion scheme constrained by actual well log data which uses a time/depth dependent seismic source function is employed to derive impedance models from 3-D and 4-D seismic datasets. The impedance values can be region grown to better isolate the low impedance hydrocarbon bearing regions. Impedance data derived from multiple 3-D seismic surveys of the same volume can be compared to identify regions of dynamic evolution and bypassed pay. Effective Oil Saturation or net oil thickness can also be derived from the impedance data and used for quantitative assessment of prospective drilling targets and reservoir management. 20 figs.

  15. Method for inverting reflection trace data from 3-D and 4-D seismic surveys and identifying subsurface fluid and pathways in and among hydrocarbon reservoirs based on impedance models

    DOEpatents

    He, Wei; Anderson, Roger N.

    1998-01-01

    A method is disclosed for inverting 3-D seismic reflection data obtained from seismic surveys to derive impedance models for a subsurface region, and for inversion of multiple 3-D seismic surveys (i.e., 4-D seismic surveys) of the same subsurface volume, separated in time to allow for dynamic fluid migration, such that small scale structure and regions of fluid and dynamic fluid flow within the subsurface volume being studied can be identified. The method allows for the mapping and quantification of available hydrocarbons within a reservoir and is thus useful for hydrocarbon prospecting and reservoir management. An iterative seismic inversion scheme constrained by actual well log data which uses a time/depth dependent seismic source function is employed to derive impedance models from 3-D and 4-D seismic datasets. The impedance values can be region grown to better isolate the low impedance hydrocarbon bearing regions. Impedance data derived from multiple 3-D seismic surveys of the same volume can be compared to identify regions of dynamic evolution and bypassed pay. Effective Oil Saturation or net oil thickness can also be derived from the impedance data and used for quantitative assessment of prospective drilling targets and reservoir management.

  16. Antifoulant additive for light end hydrocarbons

    SciTech Connect

    Dickakian, G.B.

    1990-06-05

    This patent describes a method of treating a highly paraffinic hydrocarbon liquid containing not more than 5 wt% aromatics and from 10 to 10,000 ppm high molecular weight asphaltenes to prevent asphaltene fouling of equipment at temperatures below 400{degrees} F. It comprises: adding to the hydrocarbon liquid not less than 10 ppm and not more than 200 ppm of an oil soluble overbased magnesium alkyl aromatic sulfonate to inhibit asphaltene fouling.

  17. Plasma-assisted conversion of solid hydrocarbon to diamond

    DOEpatents

    Valone, Steven M.; Pattillo, Stevan G.; Trkula, Mitchell; Coates, Don M.; Shah, S. Ismat

    1996-01-01

    A process of preparing diamond, e.g., diamond fiber, by subjecting a hydrocarbon material, e.g., a hydrocarbon fiber, to a plasma treatment in a gaseous feedstream for a sufficient period of time to form diamond, e.g., a diamond fiber is disclosed. The method generally further involves pretreating the hydrocarbon material prior to treatment with the plasma by heating within an oxygen-containing atmosphere at temperatures sufficient to increase crosslinking within said hydrocarbon material, but at temperatures insufficient to melt or decompose said hydrocarbon material, followed by heating at temperatures sufficient to promote outgassing of said crosslinked hydrocarbon material, but at temperatures insufficient to convert said hydrocarbon material to carbon.

  18. Hydrocarbon Rocket Technology Impact Forecasting

    NASA Technical Reports Server (NTRS)

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

    2012-01-01

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

  19. Emulsification of hydrocarbons by subsurface bacteria

    USGS Publications Warehouse

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

    1991-01-01

    Biosurfactants have potential for use in enhancement of in situ biorestoration by increasing the bioavailability of contaminants. Microorganisms isolated from biostimulated, contaminated and uncontaminated zones at the site of an aviation fuel spill and hydrocarbon-degrading microorganisms isolated from sites contaminated with unleaded gasoline were examined for their abilities to emulsify petroleum hydrocarbons. Emulsifying ability was quantified by a method involving agitation and visual inspection. Biostimulated-zone microbes and hydrocarbon-degrading microorganisms were the best emulsifiers as compared to contaminated and uncontaminated zone microbes. Biostimulation (nutrient and oxygen addition) may have been the dominant factor which selected for and encouraged growth of emulsifiers; exposure to hydrocarbon was also important. Biostimulated microorganisms were better emulsifiers of aviation fuel (the contaminant hydrocarbon) than of heavier hydrocarbon to which they were not previously exposed. By measuring surface tension changes of culture broths, 11 out of 41 emulsifiers tested were identified as possible biosurfactant producers and two isolates produced large surface tension reductions indicating the high probability of biosurfactant production.Biosurfactants have potential for use in enhancement of in situ biorestoration by increasing the bioavailability of contaminants. Microorganisms isolated from biostimulated, contaminated and uncontaminated zones at the site of an aviation fuel spill and hydrocarbon-degrading microorganisms isolated from sites contaminated with unleaded gasoline were examined for their abilities to emulsify petroleum hydrocarbons. Emulsifying ability was quantified by a method involving agitation and visual inspection. Biostimulated-zone microbes and hydrocarbon-degrading microorganisms were the best emulsifiers as compared to contaminated and uncontaminated zone microbes. Biostimulation (nutrient and oxygen addition) may have been

  20. Comments on Stokes' approach in determining the global gravimetric geoid and its new formulation

    NASA Astrophysics Data System (ADS)

    Shen, W. B.

    2012-04-01

    In physical geodesy, in order to determine the global gravimetric geoid, generally, a disturbing potential function, which is the difference between the geopotential and normal gravity potential, is introduced. For instance, by Stokes' approach or Stokes boundary-value problem, given the gravity anomaly on the geoid (as the boundary), a disturbing potential function satisfying some kind of boundary conditions should be solved. A basic requirement is that the disturbing potential function should be harmonic in the region outside the geoid. Besides the well-known disadvantages in the conventional Stokes' approach however, there are some theoretical difficulties. Since the normal gravity potential is not defined inside the reference ellipsoid (taking the WGS 84 ellipsoid as an example), in case that the geoid is below the ellipsoidal surface, the disturbing potential function is not harmonic in the whole region outside the geoid, and neither defined on the whole geoid itself. These are the mentioned theoretical difficulties existing in the conventional Stokes' approach. To take away these difficulties from Stokes' approach, this study provides a new formulation of Stokes' approach. We choose an inner ellipsoid with four fundamental parameters, with its center coinciding with that of the WGS 84 ellipsoid, and completely enclosed by the geoid. Then, the normal gravity potential generated by the inner ellipsoid is determined by requiring that it holds a constant on the surface of the inner ellipsoid or on the surface of the WGS 84 ellipsoid. By this new formulation, the disturbing potential function is harmonic in the whole region outside the geoid, and the difficulties existing in the conventional Stokes' approach do not exist any more. The new formulation proposed in this study is also adequate for analogous geodetic boundary-value problems. This study is supported by Natural Science Foundation China (grant No.40974015; No.41174011).

  1. GRAVIMETRIC STUDY OF THE IXTLAN DE LOS HERVORES, GEOTHERMAL AREA, MIDWESTERN MEXICAN VOLCANIC BELT (MVB)

    NASA Astrophysics Data System (ADS)

    Gonzalez, T.; Ortiz, I.

    2009-12-01

    Analysis and interpretation of gravimetric anomalies over the Occidental-Central Mexican Volcanic Belt, sheds new light on the subsurface structure of the Ixtlan de los Hervores, geothermal area. In Mexico, there are several geothermal areas that have been exploited commercially (Cerro Prieto, Los Azufres, Los Humeros, Tres Virgenes fields). However, there are many other known fields that have not been exploited. This is the case in the area of "Ixtlan de los Hervores" in the state of Michoacan. The analyzed region covers a rectangular area, aproximality from 20o N to 20.5° N and 102° W to 102.2°W. In the region there are thick basalt flows. The area is characterized by low and elongated hills formed by volcanic flows and on a smaller scale lacustrian sediments and major normal faults with a NW-SE direction particularly, the Ixtlan-Encinal fault which controls the trace of the Duero River and the Pajacuarán fault. The anomaly map was compared with the surface geology and the anomalies were correlated with major volcanic features, since our main interest was in mapping the subsurface faults and volcanic bodies. Two profiles were selected that cross major anomalies and the geothermal zone of Ixtlan. The Talwani algorithm for 2-D polygonal bodies has been used for calculating the theoretical anomalies. The proposed models adequately explain the main observed geological features. The models are made up of two lithostratigraphic units of volcanic rocks, represented by the Tertiary basalts, which adequately reflect the area's volcanic environment. These basaltic units, corresponding to different volcanic events were cut by the Ixtlan well. Both models reflect the existence of the Ixtlan-Encinal fault, the most important feature in the area which is also responsible for the existence of the geothermal area.

  2. The spherical terrain correction and its effect on the gravimetric-isostatic Moho determination

    NASA Astrophysics Data System (ADS)

    Abrehdary, M.; Sjöberg, L. E.; Bagherbandi, M.

    2016-01-01

    In this study, the Moho depth is estimated based on the refined spherical Bouguer gravity disturbance and DTM2006 topographic data using the Vening Meinesz-Moritz gravimetric-isostatic hypothesis. In this context, we compute the refined spherical Bouguer gravity disturbances in a set of 1° × 1° blocks. The spherical terrain correction, a residual correction to each Bouguer shell, is computed using rock heights and ice sheet thicknesses from the DTM2006 and Earth2014 models. The study illustrates that the defined simple Bouguer gravity disturbance corrected for the density variations of the oceans, ice sheets and sediment basins and also the non-isostatic effects needs a significant terrain correction to become the refined Bouguer gravity disturbance, and that the isostatic gravity disturbance is significantly better defined by the latter disturbance plus a compensation attraction. Our study shows that despite the fact that the lateral variation of the crustal depth is rather smooth, the terrain affects the result most significantly in many areas. The global numerical results show that the estimated Moho depths by the simple and refined spherical Bouguer gravity disturbances and the seismic CRUST1.0 model agree to 5.6 and 2.7 km in RMS, respectively. Also, the mean value differences are 1.7 and 0.2 km, respectively. Two regional numerical studies show that the RMS differences between the Moho depths estimated based on the simple and refined spherical Bouguer gravity disturbance and that using CRUST1.0 model yield fits of 4.9 and 3.2 km in South America and yield 3.2 and 3.4 km in Fennoscandia, respectively.

  3. An NMR relaxometry and gravimetric study of gelatin-free aqueous polyacrylamide dosimeters

    NASA Astrophysics Data System (ADS)

    Babic, Steven; Schreiner, L. John

    2006-09-01

    In conformal radiation therapy, a high dose of radiation is given to a target volume to increase the probability of cure, and care is taken to minimize the dose to surrounding healthy tissue. The techniques used to achieve this are very complicated and the precise verification of the resulting three-dimensional (3D) dose distribution is required. Polyacrylamide gelatin (PAG) dosimeters with magnetic resonance imaging and optical computed tomography scanning provide the required 3D dosimetry with high spatial resolution. Many basic studies have characterized these chemical dosimeters that polymerize under irradiation. However, the investigation of the fundamental properties of the radiation-induced polymerization in PAG dosimeters is complicated by the presence of the background gelatin matrix. In this work, a gelatin-free model system for the study of the basic radiation-induced polymerization in PAG dosimeters has been developed. Experiments were performed on gelatin-free dosimeters, named aqueous polyacrylamide (APA) dosimeters, containing equal amounts of acrylamide and N,N'-methylene-bisacrylamide. The APA dosimeters were prepared with four different total monomer concentrations (2, 4, 6 and 8% by weight). Nuclear magnetic resonance (NMR) spin-spin and spin-lattice proton relaxation measurements at 20 MHz, and gravimetric analyses performed on all four dosimeters, show a continuous degree of polymerization over the dose range of 0-25 Gy. The developed NMR model explains the relationship observed between the relaxation data and the amount of crosslinked polymer formed at each dose. This model can be extended with gelatin relaxation data to provide a fundamental understanding of radiation-induced polymerization in the conventional PAG dosimeters.

  4. Certification of a new series of gravimetrically prepared synthetic reference materials for n( 236U)/ n( 238U) isotope ratio measurements

    NASA Astrophysics Data System (ADS)

    Richter, Stephan; Alonso, Adolfo; Aregbe, Yetunde; Eykens, Roger; Jacobsson, Ulf; Kehoe, Frances; Kuehn, Heinz; Verbruggen, Andre; Wellum, Roger

    2010-04-01

    A new series of gravimetrically prepared synthetic isotope reference materials, the so-called IRMM-075 series, with n( 236U)/ n( 238U) isotope ratios varying from 10 -4 to 10 -9 has been prepared and certified. This series is suited for calibration of n( 236U)/ n( 238U) measurements made by various mass spectrometric techniques such as TIMS (Thermal Ionization Mass Spectrometry), ICPMS (Inductively Coupled Plasma Mass Spectrometry), AMS (Accelerator Mass Spectrometry) and RIMS (Resonance Ionization Mass Spectrometry). Natural uranium with low 236U isotope abundance and highly enriched 236U were both purified using well proven chemical methodology. The oxides were calcined into U 3O 8 in an oven installed in a glove-box with controlled humidity. Primary solutions of the same concentration were prepared by dissolving the oxides of 236U and natural U. From the 236U solution a series of four dilutions was made by weighing. Weighed amounts of the dilutions of 236U and weighed amounts of natural U were mixed to form a set of n( 236U)/ n( 238U) mixtures at a concentration of 1 mg U g -1. Verification of the mixtures IRMM-075/1-6 was performed by TIMS measurements using Faraday collectors and a secondary electron multiplier in combination with an energy filter for improved abundance sensitivity. The results agreed well with the certified values obtained from the gravimetrical mixing calculations. The uncertainties of the calculated isotopic ratios are significantly lower compared to typical uncertainties from mass spectrometric techniques such as TIMS and ICPMS and in particular to AMS and RIMS. The methods for the preparation and mixing of the IRMM-075/1-6 series are described and the certification and verification procedures are reported.

  5. Determination of the aromatic hydrocarbon to total hydrocarbon ratio of mineral oil in commercial lubricants.

    PubMed

    Uematsu, Yoko; Suzuki, Kumi; Ogimoto, Mami

    2016-03-01

    A method was developed to determine the aromatic hydrocarbon to total hydrocarbon ratio of mineral oil in commercial lubricants; a survey was also conducted of commercial lubricants. Hydrocarbons in lubricants were separated from the matrix components of lubricants using a silica gel solid phase extraction (SPE) column. Normal-phase liquid chromatography (NPLC) coupled with an evaporative light-scattering detector (ELSD) was used to determine the aromatic hydrocarbon to total hydrocarbon ratio. Size exclusion chromatography (SEC) coupled with a diode array detector (DAD) and a refractive index detector (RID) was used to estimate carbon numbers and the presence of aromatic hydrocarbons, which supplemented the results obtained by NPLC/ELSD. Aromatic hydrocarbons were not detected in 12 lubricants specified for use for incidental food contact, but were detected in 13 out of 22 lubricants non-specified for incidental food contact at a ratio up to 18%. They were also detected in 10 out of 12 lubricants collected at food factories at a ratio up to 13%. The centre carbon numbers of hydrocarbons in commercial lubricants were estimated to be between C16 and C50. PMID:26730677

  6. Integration of remotely-sensed geobotanical and structural methods for hydrocarbon exploration in West-Central West Virginia. Quartery report, May 1, 1996--July 31, 1996

    SciTech Connect

    1997-06-01

    Progress is reported on hydrocarbon exploration in West-Central West Virginia. In this period, the following tasks were carried out: a reconnaissance soil gas geochemical survey was performed at the Volcano test site and at the Lewis County test site; a geobotanical analysis of the September imagery was carried out in order to highlight spectral anomalies that appear to be associated with the historic volcano field and the Lewis County test site; and multi-temporal spectral reflectance measurements continued.

  7. Plasma Processing Of Hydrocarbon

    SciTech Connect

    Grandy, Jon D; Peter C. Kong; Brent A. Detering; Larry D. Zuck

    2007-05-01

    The Idaho National Laboratory (INL) developed several patented plasma technologies for hydrocarbon processing. The INL patents include nonthermal and thermal plasma technologies for direct natural gas to liquid conversion, upgrading low value heavy oil to synthetic light crude, and to convert refinery bottom heavy streams directly to transportation fuel products. Proof of concepts has been demonstrated with bench scale plasma processes and systems to convert heavy and light hydrocarbons to higher market value products. This paper provides an overview of three selected INL patented plasma technologies for hydrocarbon conversion or upgrade.

  8. Hydrocarbon treating process

    SciTech Connect

    Verachtert, T. A.

    1984-11-06

    A process is disclosed for treating hydrocarbon streams such as naphtha by the oxidation of mercaptans into disulfide compounds which remain in the hydrocarbon stream. The conversion is effected during passage of the hydrocarbon and an aqueous stream downward through a cylindrical mass of liquid-liquid contact material. The liquids then flow through a cylindrical screen into an annular separation zone which surrounds a lower part of the contact material. After decantation in the separation zone, the aqueous material, which preferably contains the oxidation catalyst, is recycled.

  9. Total organic carbon and gas chromatography-mass spectroscopy methods to determine total carbon and hydrocarbons in mercuric iodide single crystals

    NASA Astrophysics Data System (ADS)

    Steinberg, S.; Kaplan, I.; Schieber, M.; Ortale, C.; Skinner, N.; van den Berg, L.

    1989-11-01

    Total organic carbon was determined by measuring the CO2 produced by combustion in a sealed quartz vessel. The CO2 was quantified by nondispersive IR and by titration using commercial detectors. The total organic carbon was found to be around 10-100 μg/g in both starting materials and in single crystals. Gas chromatography-mass spectroscopy (GC/MS) measurements were made on hexane extracts of mercuric iodide (HgI2) dissolved in potassium iodide solution. Hydrocarbons starting with C10 (DIENE) and up to C26 were found. In addition, phthalates, such as diethyl and dioctyl phthalate were also found. Some of the organic compounds, for example, such hydrocarbons as branched nC16, nC20, nC21, nC22, nC23, and nC24, were present in some HgI2 materials in quantities of the order of weight ppm, but were eliminated in the purification process and were not found in the single crystals. Other organic compounds such as the phthalates were not always eliminated and were identified in the single crystals. In general, the GC/MS could identify only hydrocarbons of C10 and higher which account for only a few percent of the total organic carbon determined by oxidation.

  10. Design and realization of the high-precision weighing systems as the gravimetric references in PTB's national water flow standard

    NASA Astrophysics Data System (ADS)

    Engel, Rainer; Beyer, Karlheinz; Baade, Hans-Joachim

    2012-07-01

    PTB's ‘Hydrodynamic Test Field’, which represents a high-accuracy water flow calibration facility, serves as the national primary standard for liquid flow measurands. As the core reference device of this flow facility, a gravimetric standard has been incorporated, which comprises three special-design weighing systems: 300 kg, 3 tons and 30 tons. These gravimetric references were realized as a combination of a strain-gauge-based and an electromagnetic-force-compensation load-cell-based balance, each. Special emphasis had to be placed upon the dynamics design of the whole weighing system, due to the high measurement resolution and the dynamic behavior of the weighing systems, which are dynamically affected by mechanical vibrations caused by environmental impacts, flow machinery operation, flow noise in the pipework and induced wave motions in the weigh tanks. Taking into account all the above boundary conditions, the design work for the gravimetric reference resulted in a concrete foundation ‘rock’ of some 300 tons that rests on a number of vibration isolators. In addition to these passively operating vibration isolators, the vibration damping effect is enhanced by applying an electronic level regulation device.

  11. Hydrocarbon and nonhydrocarbon derivatives of cyclopropane

    NASA Technical Reports Server (NTRS)

    Slabey, Vernon A; Wise, Paul H; Gibbons, Louis C

    1953-01-01

    The methods used to prepare and purify 19 hydrocarbon derivatives of cyclopropane are discussed. Of these hydrocarbons, 13 were synthesized for the first time. In addition to the hydrocarbons, six cyclopropylcarbinols, five alkyl cyclopropyl ketones, three cyclopropyl chlorides, and one cyclopropanedicarboxylate were prepared as synthesis intermediates. The melting points, boiling points, refractive indices, densities, and, in some instances, heats of combustion of both the hydrocarbon and nonhydrocarbon derivatives of cyclopropane were determined. These data and the infrared spectrum of each of the 34 cyclopropane compounds are presented in this report. The infrared absorption bands characteristic of the cyclopropyl ring are discussed, and some observations are made on the contribution of the cyclopropyl ring to the molecular refractions of cyclopropane compounds.

  12. Hydrocarbon recovery from diatomite

    SciTech Connect

    Scinta, J.

    1984-05-15

    Supercritical extraction of diatomaceous earth results in a much more significant improvement in hydrocarbon recovery over Fischer retorting than achievable with tar sands. Process and apparatus for supercritical extraction of diatomaceous earth are disclosed.

  13. Membrane separation of hydrocarbons

    DOEpatents

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

    1986-01-01

    Mixtures of heavy oils and light hydrocarbons may be separated by passing the mixture over a polymeric membrane which comprises a polymer capable of maintaining its integrity in the presence of hydrocarbon compounds at temperature ranging from about ambient to about 100.degree. C. and pressures ranging from about 50 to about 1000 psi. The membranes which possess pore sizes ranging from about 10 to about 500 Angstroms are cast from a solvent solution and recovered.

  14. Hydrocarbon geoscience research strategy

    SciTech Connect

    Not Available

    1990-04-01

    This document outlines a strategy for oil and gas related research focused on optimizing the economic producibility of the Nation's resources. The Hydrocarbon Geoscience Strategy was developed by the Hydrocarbon Geoscience Research Coordinating Committee of the Department of Energy (DOE). This strategy forms the basis for the development of DOE Fossil Energy's Oil Research Program Implementation Plan and Natural Gas Program Implementation Plan. 24 refs., 5 figs., 3 tabs.

  15. Gravimetric 3D Subsurface Modelling of the Cerro Do Jarau Structure, Rio Grande Do Sul, Brazil.

    NASA Astrophysics Data System (ADS)

    Giacomini, B. B.

    2014-12-01

    Although common in other bodies of the solar system, impact craters formed in basaltic terrains are rare on Earth and only a few examples are known. Two of these craters are located south of Brazil, the Vargeão and Vista Alegre impact craters. The Cerro do Jarau structure is not confirmed, but is a possible third Brazilian basaltic crater, formed above the Serra Geral basalt floods of the Paraná Basin like the other two. Cerro do Jarau is a 13 km circular landform that rises over 200 meters above the plains of the "pampas" in southern Brazil. The name, meaning "Jarau hills", is given after the crests of silicified and deformed Botucatu sandstones, which form a semiring of elevated hills in the northern part of the structure. This work focused on the construction of a 3D subsurface geological model that could explain a new set of ground gravimetric data. Bouguer anomalies were calculated from gravity acceleration measured at 313 stations irregularly distributed on the area of the impact structure. A regional component represented by a polynomial trend surface was extracted from the total Bouguer anomalies. The residual Bouguer map (fig. 1) shows a strong positive anomaly with a NE-SW trend, located in the northeastern part of the structure. This gravity feature is not common in other impact structures, being possibly related to a dike intrusion. However, the negative anomaly present in the center of the structure and the circular positive anomaly surrounding the central part of the structure could be related to an impact structure. The positive circular anomaly is not spatially coincident with the edges of the structure, a feature that is also observed at the Vargeão and Vista Alegre impact structures. Density values of basalts, sandstones and breccias were measured from rock samples and each average value were used as constraints for the 3D model developed with the Geosoft® VOXI Earth modelling.This model provided a better understanding of the subsurface design

  16. New Geomagnetic and Gravimetric Images of The Chicxulub Impact, Yucatan, Mexico

    NASA Astrophysics Data System (ADS)

    Meyer, U.; Urrutia-Fucugauchi, J.; Rebolledo, M.; Lara, J.

    The GeoForschungsZentrum Potsdam (GFZ) conducted in co-operation with the Uni- versidad Nacional Autónoma de México (UNAM) and the Consejo de Recursos Min- erales (CRM) 17 survey flights over the northern part of the Chicxulub impact struc- ture in the time frame from February 8th to February 24th, 2001. The aerogravimetry system of the GFZ was installed in a Britten-Norman Islander (BN-212), a small twin- engine aircraft so far used only for aeromagnetic surveys of the CRM. All flights in the area of interest were conducted from Mérida. GPS reference stations were installed in Mérida, Progreso and Celestun. The main profiles were flown in E-W-direction with a line spacing of 5 km and N-S-crossings of 30 km. The flight level was 600 ft over wa- ter and 1500 ft over land. The higher flight level on-shore was imperative due to safety regulations and turbulence effects being a compromise between resolution and flight stability. The main goal of the airborne survey was to fly aerogravimetry and aero- magnetometry over the Chicxulub impact structure in the northern part of Yucatán. To the present knowledge, the Chicxulub crater was caused by a meteorite impact about 65 million year before present. It is believed that among other events (large magmatic events in the Dekka region) this impact was mainly responsible for the mass extinction marking the Cretaceous-Tertiary-boundary. The northern part of the impact structure is buried under the sediments and shallow water of the southern Gulf of Mexico. This part is not accessible for research vessels because of its riffs and shoals close to the coast. Consequently, a large data gap remained in the most important, central part of the Chicxulub crater. Therefore, we mapped this area by aerogeophysical means to acquire geomagnetic and gravimetric images of strongly improved quality and resolu- tion. Both new data sets are used to discuss so far existing interpretations and models of the Chicxulub structure. Moreover, a

  17. Mixture including hydrogen and hydrocarbon having pressure-temperature stability

    NASA Technical Reports Server (NTRS)

    Mao, Wendy L. (Inventor); Mao, Ho-Kwang (Inventor)

    2009-01-01

    The invention relates to a method of storing hydrogen that employs a mixture of hydrogen and a hydrocarbon that can both be used as fuel. In one embodiment, the method involves maintaining a mixture including hydrogen and a hydrocarbon in the solid state at ambient pressure and a temperature in excess of about 10 K.

  18. Hydrocarbon potential and exploration methods within cretaceous of Utah-Wyoming overthrust belt: a new frontier in a not-so-old area

    SciTech Connect

    Bertagne, A.J.; Boettcher, J.W.; Vuillermoz, C.

    1986-05-01

    A largely untested stratigraphic play exists within the Cretaceous section of the Utah-Wyoming Overthrust belt. Coarse Cretaceous sediments on the western Absaroka plate merge gradationally eastward into a predominantly shale section, which sets up the potential for Cretaceous sands to pinch out within Cretaceous shale in the Overthrust belt. The discovery well in this play is the Sam Gary Jr. 4-6X Lazeart with a reported initial potential of 87 BOPD from the Upper Cretaceous Frontier Formation. The anticipated source of hydrocarbons is Cretaceous shale - the documented source of most hydrocarbons found to date in the Utah-Wyoming Overthrust belt. Published research indicates that Cretaceous shales have reached adequate maturation levels under the Darby and Absaroka plates and probably on the back of the Absaroka plate. In addition, hydrocarbons may have moved updip from the generation area to shallower reservoirs as a result of secondary migration. Therefore, the geographic area of the play is extensive. State-of-the-art seismic data are an essential prerequisite for systematic exploration of the Cretaceous play. After acquiring a regional seismic grid and tying in well control and surface geology, the following procedure should be implemented: (1) use seismic reflections to establish a regional chronostratigraphic framework, (2) interpret seismic facies to determine geographic distribution of depositional environments, and (3) perform detailed interpretation and forward modeling to locate specific prospects. A reprocessed seismic line from the Overthrust belt confirms that data quality is high enough to use this procedure. An aggressive exploration program in this area is likely to result in significant reserve additions; a commitment to the search for the subtle trap in the Overthrust belt is now needed.

  19. A study of hydrocarbon migration events: Development and application of new methods for constraining the time of migration and an assessment of rock-fluid interactions. Final report, September 1, 1991--August 31, 1994

    SciTech Connect

    Elmore, R.D.; Engel, M.H.

    1993-12-31

    The authors are conducting the research to test and refine a paleomagnetic method for dating hydrocarbon migration, and to assess the chemical alteration of crude oils resulting from fluid-rock interactions. Samples were collected for paleomagnetic and organic geochemical investigations from several units. These include the Old Red Sandstone in Scotland, and the Schoolhouse Member of the Maroon Formation and the Belden Formation in Colorado. Studies of these units are completed or underway. In addition, simulation experiments, where the authors are attempting to form magnetite in the laboratory, are underway.

  20. Method for thermal cracking of hydrocarbons in an apparatus of an alloy having alkali or alkaline earth metals in the alloy to minimize coke deposition

    SciTech Connect

    Watanabe, Y.; Morimura, T.; Toyoda, Y.

    1984-06-12

    In the thermal cracking of or heating of hydrocarbons, for example naphtha, a carbonization reaction incidentally takes place due to the fact that Ni, Fe and Co contained in, for example, the conduits of the thermal cracking apparatus have a catalytically carbonizing action. The aim of the present invention is to effectively suppress carbon deposition promoted by these elements, to provide for the incorporation of an inhibitor element, e.g. Li, Na, Ba, Be, Ca, Mg or their oxides, into the heat-resistant alloy, and to form on the surface of this alloy a carbon deposition suppressing layer which comprises an inhibitor element.

  1. Apparatus for heat induced separation of hydrocarbon constituents from coal

    SciTech Connect

    Pine, M.; Johnson, J.R.; Moss, R.E.; Sandoval, R.A.

    1984-09-25

    A method and apparatus is provided for accomplishing thermal separation of various hydrocarbons and other compounds from coal, a hydrocarbon rendering module is provided for the continuous agitation and circulation of coal during the rendering period and utilizes thermal trays having stationary and revolving apparatus to improve heat transfer to coal particles and minimize rendering time. Portions of the rendered hydrocarbon products are recycled to the mechanism as an energy source for continuous operation.

  2. Comparison of Factorial Kriging Analysis Method and Upward Continuation Filter to Recognize Subsurface Structures - A Case Study: Gravity Data from a Hydrocarbon Field in the Southeast Sedimentary Basins of the East Vietnam Sea

    NASA Astrophysics Data System (ADS)

    Azad, Mohammad-Reza; Koneshloo, Mohammad; Kamakar Rouhani, Abolghasem; Aghajani, Hamid

    2016-04-01

    To interpret geophysical anomaly maps, it is necessary to filter out regional and sometimes noise components. Each measured value in a gravity survey consists of different components. Upward continuation (UC) is one of the most widely used filters. The shortcoming of this filter is not to consider the spatial structure of the data, and also the fact that the trial and error approach and expert's judgment are needed to adjust it. This study aims to compare the factorial kriging analysis (FKA) and UC filters for separation of local and regional anomalies in the gravity data of a hydrocarbon field in the southeast sedimentary basins of the East Vietnam Sea. As shown in this paper, FKA method permits to filter out all of the identified structures, while the UC filter does not possess this capability. Therefore, beside general and classic filtering methods, the FKA method can be used as a strong method in filtering spatial structures and anomaly component.

  3. Research on dual-wavelength photometric method for micro liquid volume measurement

    NASA Astrophysics Data System (ADS)

    Wang, Jintao; Liu, Ziyong; Tong, Lin

    2015-02-01

    In order to overcome the shortcoming of significant influence of evaporation capacity on gravimetric method and meet the requirement of online measurement, dual-wavelength photometric method is introduced for measuring microliquid volume. Based on Lambert-Beer law, this paper introduces the dual-wavelength photometric method (DWP method) at 520 nm and 730 nm, which can measure the microliquid volume through the linear relation between the concentration of dilute solution and the absorbance. Comparing to gravimetric method, an experimental system for dual-wavelength photometric method was designed. Experimental results indicate that the test result obtained by using DWP method was better than obtained by using gravimetric method, and met the technical requirement of ISO 8655. Compared with the gravimetric method, the non-gravimetric methods can provide a better solution for microliquid volume measurement, which was less stringent for measurement environment, easy to realize the online calibration and capable of reducing the influence of liquid evaporation.

  4. Using supercritical fluids to refine hydrocarbons

    DOEpatents

    Yarbro, Stephen Lee

    2014-11-25

    This is a method to reactively refine hydrocarbons, such as heavy oils with API gravities of less than 20.degree. and bitumen-like hydrocarbons with viscosities greater than 1000 cp at standard temperature and pressure using a selected fluid at supercritical conditions. The reaction portion of the method delivers lighter weight, more volatile hydrocarbons to an attached contacting device that operates in mixed subcritical or supercritical modes. This separates the reaction products into portions that are viable for use or sale without further conventional refining and hydro-processing techniques. This method produces valuable products with fewer processing steps, lower costs, increased worker safety due to less processing and handling, allow greater opportunity for new oil field development and subsequent positive economic impact, reduce related carbon dioxide, and wastes typical with conventional refineries.

  5. Certification of new Pb iCRM (Candidate ERM-38xx series) via Gravimetric Isotope Mixtures and MC-ICP-MS Measurements

    NASA Astrophysics Data System (ADS)

    Ponzevera, E.; Quetel, C. R.

    2008-12-01

    Lead is known to be a particularly toxic chemical element. Mining and smelting of Pb and its domestic use over the centuries have contaminated the surface of Earth and jeopardized the health of humans, domestic animals and wildlife. Omnipresence of Pb has however an advantage. It can be used as an isotopic tracer of pollution sources and pathways in the environment. Pb isotopic Certified Reference Materials (iCRM) with undisputed characteristics are then required to validate Pb isotope ratio measurements. The materials currently available worldwide were produced in the 1960's by the National Bureau of Standards (now NIST, USA) and are now the object of polemics regarding the accuracy of some of the accompanying certified values. Moreover, new materials with lower relative uncertainty statements are demanded by users. This presentation is centred on the production and the certification at the EC-JRC-Institute for Reference Materials and Measurements of a new series of Pb iCRM (candidate ERM-38xx series). The production included six Pb gravimetric isotope mixtures, a common Pb material dedicated to routine calibration work and a series of four 207Pb slightly enriched natural-like Pb materials for the validation of the δ-scale method below 0.01%. The gravimetric isotope mixtures method, originally supported by mass spectrometry measurements performed on GS-MS or TI-MS instruments, was applied successfully to MC-ICP-MS. The measurements and certification methods we developed were validated in several ways, including a systematic investigation on possible significant sources of uncertainty and comparisons of results obtained by different laboratories on identical samples. Relative uncertainties on isotope ratios obtained for the newly produced Pb iCRM are as low as 0.017%, which is between 2 and 4 times smaller than the uncertainties carried by the NIST-981 material. Going below 0.01% was not possible mainly because of uncompressible uncertainties coming from the

  6. Thermal cracking of hydrocarbons

    SciTech Connect

    Braun, R.L.; Burnham, A.K.

    1988-09-01

    Knowledge of thermal cracking of hydrocarbons is important in understanding and modeling petroleum maturation. We have reviewed the literature on the thermal cracking of pure hydrocarbons and mixtures of hydrocarbons, with particular attention given to dependence of the kinetics on temperature, pressure, and phase. Major uncertainties remain with regard to pressure dependence. Based on this review, we developed a simple, four-component, three-reaction model for oil-cracking. We also developed a simple, kerogen-maturation, kinetic model that incorporates hydrogen and carbon balance and includes the most important oil- and gas-forming reactions: kerogen pyrolysis, three oil-cracking reactions, and three coke-pyrolysis reactions. Tentative stoichiometry parameters are given for lacustrine and marine kerogens. 35 refs., 5 figs., 5 tabs.

  7. Prediction of flame velocities of hydrocarbon flames

    NASA Technical Reports Server (NTRS)

    Dugger, Gordon L; Simon, Dorothy M

    1954-01-01

    The laminar-flame-velocity data previously reported by the Lewis Laboratory are surveyed with respect to the correspondence between experimental flame velocities and values predicted by semitheoretical and empirical methods. The combustible mixture variables covered are hydrocarbon structure (56 hydrocarbons), equivalence ratio of fuel-air mixture, mole fraction of oxygen in the primary oxygen-nitrogen mixture (0.17 to 0.50), and initial mixture temperature (200 degrees to 615 degrees k). The semitheoretical method of prediction considered are based on three approximate theoretical equations for flame velocity: the Semenov equation, the Tanford-Pease equation, and the Manson equation.

  8. Identification of active faults in Abruzzo area (central Italy) through the analysis of geological, seismological and gravimetric data

    NASA Astrophysics Data System (ADS)

    Luiso, Paola; Paoletti, Valeria; Gaudiosi, Germana; Nappi, Rosa; Cella, Federico; Fedi, Maurizio

    2016-04-01

    Identification of active faults in abruzzo area (central italy) through the analysis of geological, seismological and gravimetric data The aim of this study is to identify and constrain the geometry of the seismogenic structures (active, outcropping and buried fault systems) of the Abruzzo area (central Italy), through an integrated analysis of geo-structural, seismic and gravimetric data. We generated three thematic: "faults", "earthquakes" and "gravimetric" data: i) The fault dataset consists of data extracted from the available structural and geological maps (ITHACA catalogue; the "Neotectonic Map of Italy" 1:500.000; several geological sheets 1:50.000 from ISPRA CARG project; the Geological Map 1:100.000 Sheet 1), and many geological studies. ii) The earthquakes datasets was created by merging the data from historical and instrumental Catalogues (CPTI04 and CPTI11; ISIDE - INGV). iii) The gravimetric datasets consists in the Multiscale Derivative Analysis (MDA) of the Bouguer anomaly map of the area, whose maxima show the presence of density lineaments. The merge of these datasets in GIS environment, highlighted four possible scenarios of correlation between faults, earthquakes and MDA maxima: 1) the existence of active faults, revealed by a strong correlation between epicentral location of seismic clusters, fault positions and MDA maxima; 2) the existence of buried active faults, highlighted by a good correlation between MDA maxima and epicentral positions, without correspondence with faults known from geological data; 3) the existence of inactive or silent faults, detected by the presence of faults reported in the geological datasets and literature which are associated with MDA maxima, without correlation of earthquakes; 4) the existence of faults not correlated with MDA maxima; this could be due to faults putting in contact two lithologies with a similar density. A comparison between seismic hypocentral locations and the fault geometry retrieved by DEXP

  9. Hydrocarbon fuel detergent

    SciTech Connect

    Meyer, G.R.; Lyons, W.R.

    1990-01-23

    This patent describes a hydrocarbon fuel composition comprising: a hydrocarbon fuel; and a detergent amount of a detergent comprising an alkenylsuccinimide prepared by reacting an alkenylsuccinic acid or anhydride with a mixture of amines, wherein at least 90 weight percent of the alkenyl substituent is derived from an olefin having a carbon chain of from 10 to 30 carbons or mixtures thereof, and wherein the alkenylsuccinic acid or anhydride is reacted with the mixture of amines at a mole ratio of 0.8 to 1.5 moles of the amines per mole of the alkenylsuccinic acid or anhydride.

  10. Quantitative Hydrocarbon Surface Analysis

    NASA Technical Reports Server (NTRS)

    Douglas, Vonnie M.

    2000-01-01

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

  11. Absorption of polycyclic aromatic hydrocarbons by Pinus bark: analytical method and use for environmental pollution monitoring in the Palermo area (Sicily, Italy).

    PubMed

    Orecchio, Santino; Gianguzza, Antonio; Culotta, Loredana

    2008-07-01

    In the light of using biomaterial as pollutants sorbents for the environmental biomonitoring, we report here the results of the absorption of polycyclic aromatic hydrocarbons (PAHs) by pine bark. Quantitative analysis of 19 different polycyclic aromatic compounds was performed, after Soxhlet extraction in dichloromethane, by means GC-MS technique. Pinus was chosen due to its wide distribution in the Mediterranean area. The passive absorption of PAH by pine bark in the metropolitan areas allowed us to evaluate the air quality of Palermo. The obtained results showed a very high range of PAHs concentrations, from 33 microg/kg (bark dry weight), as SigmaPAHs, at the control site to 1015 microg/kg along a road with high traffic flow. PMID:18417111

  12. HYDROCARBON POLLUTANTS FROM STATIONARY SOURCES

    EPA Science Inventory

    The report gives results of a study of hydrocarbon pollutants from stationary sources. Early in the study, readily available information was assembled on stationary sources of hydrocarbon emissions and effluents. Information was also obtained on process descriptions, operating pa...

  13. Apparatus for recovering gaseous hydrocarbons from hydrocarbon-containing solid hydrates

    DOEpatents

    Elliott, Guy R. B.; Barraclough, Bruce L.; Vanderborgh, Nicholas E.

    1984-01-01

    A method and apparatus are provided for producing gaseous hydrocarbons from formations comprising solid hydrocarbon hydrates located under either a body of land or a body of water. The vast natural resources of such hydrocarbon hydrates can thus now be economically mined. Relatively warm brine or water is brought down from an elevation above that of the hydrates through a portion of the apparatus and passes in contact with the hydrates, thus melting them. The liquid then continues up another portion of the apparatus, carrying entrained hydrocarbon vapors in the form of bubbles, which can easily be separated from the liquid. After a short startup procedure, the process and apparatus are substantially self-powered.

  14. Selecting hydrocarbon rocket propulsion technology

    NASA Technical Reports Server (NTRS)

    Martin, J. A.

    1986-01-01

    Past studies have shown that the dry weight of future earth-to-orbit vehicles can be reduced by the combined use of hydrogen and hydrocarbon propulsion compared to all-hydrogen propulsion. This paper shows that the use of certain hydrocarbon engines with hydrogen engines produces the lowest vehicle dry mass. These hydrocarbon engines use propane or RP-1 fuel, hydrogen cooling, and hydrogen-rich gas generators. Integration of the hydrogen and hydrocarbon nozzles is also beneficial.

  15. Hydrocarbon options emerge

    SciTech Connect

    Fairley, P.

    1995-11-01

    Europe stole the scene at last week`s International Chlorofluorocarbon (CFC) and Halon Alternatives Conference in Washington as attendees learned more about an accelerating shift to low-cost hydrocarbon refrigerants by European equipment manufacturers. Udo Wenning, representing German refrigerator market leader Bosch-Siemens, told the conference that hydrocarbons-isobutane as refrigerant and cyclopentane to blow the insulating foam-are now used in 90% of German production. Wenning says that in all performance parameters, hydrocarbons match the hydrochlorofluorocarbon (HCFC) and hydrofluorocarbon (HFC) replacements favored in the U.S. and Japan and that, unlike HCFCs and HFCs they have low global warming potential. Their Achille`s heel is flammability, Wenning says. American equipment manufacturers aiming to sell a new generation of equipment designed for the new HFC refrigerants sought to amplify concern over flammability at the conference. {open_quotes}In a society as litigious as ours, we do not see a future for flammable refrigerants,{close_quotes} says a representative of air conditioner manufacturer Carrier. Hydrocarbon supporters such as Greenpeace say the risks are mananageable.

  16. Optrode for sensing hydrocarbons

    DOEpatents

    Miller, H.; Milanovich, F.P.; Hirschfeld, T.B.; Miller, F.S.

    1987-05-19

    A two-phase system employing the Fujiwara reaction is provided for the fluorometric detection of halogenated hydrocarbons. A fiber optic is utilized to illuminate a column of pyridine trapped in a capillary tube coaxially attached at one end to the illuminating end of the fiber optic. A strongly alkaline condition necessary for the reaction is maintained by providing a reservoir of alkali in contact with the column of pyridine, the surface of contact being adjacent to the illuminating end of the fiber optic. A semipermeable membrane caps the other end of the capillary tube, the membrane being preferentially permeable to the halogenated hydrocarbon but preferentially impermeable to water and pyridine. As the halogenated hydrocarbon diffuses through the membrane and into the column of pyridine, fluorescent reaction products are formed. Light propagated by the fiber optic from a light source, excites the fluorescent products. Light from the fluorescence emission is also collected by the same fiber optic and transmitted to a detector. The intensity of the fluorescence gives a measure of the concentration of the halogenated hydrocarbons. 6 figs.

  17. Optrode for sensing hydrocarbons

    DOEpatents

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

    1988-01-01

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

  18. Optrode for sensing hydrocarbons

    DOEpatents

    Miller, H.; Milanovich, F.P.; Hirschfeld, T.B.; Miller, F.S.

    1988-09-13

    A two-phase system employing the Fujiwara reaction is provided for the fluorometric detection of halogenated hydrocarbons. A fiber optic is utilized to illuminate a column of pyridine trapped in a capillary tube coaxially attached at one end to the illuminating end of the fiber optic. A strongly alkaline condition necessary for the reaction is maintained by providing a reservoir of alkali in contact with the column of pyridine, the surface of contact being adjacent to the illuminating end of the fiber optic. A semipermeable membrane caps the other end of the capillary tube, the membrane being preferentially permeable to the halogenated hydrocarbon and but preferentially impermeable to water and pyridine. As the halogenated hydrocarbon diffuses through the membrane and into the column of pyridine, fluorescent reaction products are formed. Light propagated by the fiber optic from a light source, excites the fluorescent products. Light from the fluorescence emission is also collected by the same fiber optic and transmitted to a detector. The intensity of the fluorescence gives a measure of the concentration of the halogenated hydrocarbons. 5 figs.

  19. Optrode for sensing hydrocarbons

    DOEpatents

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

    1987-01-01

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

  20. Zeroing in on hydrocarbons

    SciTech Connect

    Roest, I.P.B. van der; Brasser, D.J.S.; Wagebaert, A.P.J.; Stam, P.H.

    1997-05-01

    The increasing costs of remediating contaminated sites has stimulated research for cost-reducing techniques in soil investigation and cleanup techniques. MAP Environmental Research has developed a technology using ground penetrating radar in combination with in house developed software to locate and define the extent of hydrocarbon contamination. This article discusses the new technology. 2 figs.

  1. Source identification of petroleum hydrocarbons in soil and sediments from Iguaçu River Watershed, Paraná, Brazil using the CHEMSIC method (CHEMometric analysis of Selected Ion Chromatograms).

    PubMed

    Gallotta, Fabiana D C; Christensen, Jan H

    2012-04-27

    A chemometric method based on principal component analysis (PCA) of pre-processed and combined sections of selected ion chromatograms (SICs) is used to characterise the hydrocarbon profiles in soil and sediment from Araucária, Guajuvira, General Lúcio and Balsa Nova Municipalities (Iguaçu River Watershed, Paraná, Brazil) and to indicate the main sources of hydrocarbon pollution. The study includes 38 SICs of polycyclic aromatic compounds (PACs) and four of petroleum biomarkers in two separate analyses. The most contaminated samples are inside the Presidente Getúlio Vargas Refinery area. These samples represent a petrogenic pattern and different weathering degrees. Samples from outside the refinery area are either less or not contaminated, or contain mixtures of diagenetic, pyrogenic and petrogenic inputs where different proportions predominate. The locations farthest away from industrial activity (Balsa Nova) contains the lowest levels of PAC contamination. There are no evidences to conclude positive matches between the samples from outside the refinery area and the Cusiana spilled oil. PMID:22417888

  2. Assessing dry density and gravimetric water content of soils in geotechnics with complex conductivity measurements : preliminary investigations

    NASA Astrophysics Data System (ADS)

    Kaouane, C.; Beck, Y.; Fauchard, C.; Chouteau, M.

    2012-12-01

    Quality controls of geotechnical works need gravimetric water content (w) and dry density (γd) measurements. Afterwards, results are compared to Proctor tests and referred to soil classification. Depending on the class of soils, different objectives must be achieved. Those measurements are usually carried out with neutron and gamma probes. Combined use of theses probes directly access (w, γd). Theses probes show great disadvantages as: nuclear hazard, heavy on-site, transporation and storage restrictions and low sampling volumes. Last decades showed a strong development of electrical and electromagnetic methods for mapping water content in soils. Still, their use in Geotechnics is limited due to interfacial effects neglected in common models but strong in compacted soils. We first showed that (w, γd) is equivalent to (φ, Sr) assuming density of particles γs=2.7 (g.cm-3). This assumption is true for common soils used in civil engineering. That first relationship allows us to work with meaningful parameters for geophysicists. Revil&Florsh recently adapted Vinegar&Waxman model for Spectal Induced Polarization (SIP) measurements at low frequencies (<50 kHz). This model relates quantitatively the electrical double layer polarization at the surface of grains. It takes into account saturation, porosity and granulometry. Standard granulometry and mineralogy are generally available in geotechnical campaigns. In-phase conductivity would be mostly related to saturation as quadrature conductivity would be related to porosity and surface conductivity. Although this model was developed for oil-bearing sands, we investigated its potential for compacted soils. Former DC-resistivity (ρ) measurements were carried out on a silty fined-grained soil (A1 in GTR classification or ML-CL in USCS) in a cylindrical cell (radius ~4 cm, heigth 7 cm). Median diameter of grain was 50 μm. For each measurement, samples were compacted at Proctor energy. We assessed (w, γd) by weighting and

  3. Autothermal reforming of aliphatic and aromatic hydrocarbon liquids

    NASA Technical Reports Server (NTRS)

    Flytzani-Stephanopoulos, M.; Voecks, G. E.

    1983-01-01

    Results are presented from a study of the autothermal reforming of paraffins and aromatics over nickel catalysts. The trials were performed to examine the carbon products that appear when steam is passed over hydrocarbon liquids to form H2-rich gases, i.e., the autothermal process (ATR). Attention was given to n-hexane, n-tetradecane, benzene, and benzene solutions of naphthalene with reactant preheat to 1000-1150 F. The carbon-formation limit was sought as a function of the steam-to-carbon and oxygen to carbon molar ratios at constant pressure and the preheat temperatures. The catalyst bed was examined after each trial to identify the locations and types of carbon formed using SEM, thermal gravimetric analysis, and X ray diffraction techniques. The hydrocarbon fuels each had a separate temperature and reaction profile, as well as carbon formation characteristics. No carbon formation was observed in the upper layer of the reactor bed, while both gas phase and surface-grown deposits were present in the lower part. The results are concluded of use in the study of No. 2 fuel oil for ATR feedstock.

  4. Mantle hydrocarbons: Abiotic or biotic?

    SciTech Connect

    Sugisaki, Ryuichi; Mimura, Koichi

    1994-06-01

    Analyses of 227 rocks from fifty localities throughout the world showed that mantle derived rocks such as tectonized peridotites in ophiolite sequences (tectonites) and peridotite xenoliths in alkali basalts contain heavier hydrocarbons (n-alkanes), whereas igneous rocks produced by magmas such as gabbro and granite lack them. The occurrence of hydrocarbons indicates that they were not derived either from laboratory contamination or from field contamination; these compounds found in the mantle-derived rocks are called here {open_quotes}mantle hydrocarbons.{close_quotes} The existence of hydrocarbons correlates with petrogenesis. For example, peridotite cumulates produced by magmatic differentiation lack hydrocarbons whereas peridotite xenoliths derived from the mantle contain them. Gas chromatographic-mass spectrometric records of the mantle hydrocarbons resemble those of aliphatics in meteorites and in petroleum. Features of the hydrocarbons are that (a) the mantle hydrocarbons reside mainly along grain boundaries and in fluid inclusions of minerals; (b) heavier isoprenoids such as pristane and phytane are present; and (c) {delta}{sup 13}C of the mantle hydrocarbons is uniform (about {minus}27{per_thousand}). Possible origins for the mantle hydrocarbons are as follows. (1) They were inorganically synthesized by Fischer-Tropsch type reaction in the mantle. (2) They were delivered by meteorites and comets to the early Earth. (3) They were recycled by subduction. The mantle hydrocarbons in the cases of (1) and (2) are abiogenic and those in (3) are mainly biogenic. It appears that hydrocarbons may survive high pressures and temperatures in the mantle, but they are decomposed into lighter hydrocarbon gases such as CH{sub 4} at lower pressures when magmas intrude into the crust; consequently, peridotite cumulates do not contain heavier hydrocarbons but possess hydrocarbon gases up to C{sub 4}H{sub 10}. 76 refs., 5 figs., 3 tabs.

  5. Mantle hydrocarbons: abiotic or biotic?

    PubMed

    Sugisaki, R; Mimura, K

    1994-06-01

    Analyses of 227 rocks from fifty localities throughout the world showed that mantle derived rocks such as tectonized peridotites in ophiolite sequences (tectonites) arid peridotite xenoliths in alkali basalts contain heavier hydrocarbons (n-alkanes), whereas igneous rocks produced by magmas such as gabbro arid granite lack them. The occurrence of hydrocarbons indicates that they were not derived either from laboratory contamination or from held contamination; these compounds found in the mantle-derived rocks are called here "mantle hydrocarbons." The existence of hydrocarbons correlates with petrogenesis. For example, peridotite cumulates produced by magmatic differentiation lack hydrocarbons whereas peridotite xenoliths derived from the mantle contain them. Gas chromatographic-mass spectrometric records of the mantle hydrocarbons resemble those of aliphatics in meteorites and in petroleum. Features of the hydrocarbons are that (a) the mantle hydrocarbons reside mainly along grain boundaries and in fluid inclusions of minerals; (b) heavier isoprenoids such as pristane and phytane are present; and (c) delta 13C of the mantle hydrocarbons is uniform (about -27%). Possible origins for the mantle hydrocarbons are as follows. (1) They were in organically synthesized by Fischer-Tropsch type reaction in the mantle. (2) They were delivered by meteorites and comets to the early Earth. (3) They were recycled by subduction. The mantle hydrocarbons in the cases of (1) and (2) are abiogenic and those in (3) are mainly biogenic. It appears that hydrocarbons may survive high pressures and temperatures in the mantle, but they are decomposed into lighter hydrocarbon gases such as CH4 at lower pressures when magmas intrude into the crust; consequently, peridotite cumulates do not contain heavier hydrocarbons but possess hydrocarbon gases up to C4H10. PMID:11541663

  6. Mantle hydrocarbons: Abiotic or biotic?

    NASA Astrophysics Data System (ADS)

    Sugisaki, Ryuichi; Mimura, Koichi

    1994-06-01

    Analyses of 227 rocks from fifty localities throughout the world showed that mantle derived rocks such as tectonized peridotites in ophiolite sequences (tectonites) and peridotite xenoliths in alkali basalts contain heavier hydrocarbons ( n-alkanes), whereas igneous rocks produced by magmas such as gabbro and granite lack them. The occurrence of hydrocarbons indicates that they were not derived either from laboratory contamination or from field contamination; these compounds found in the mantle-derived rocks are called here "mantle hydrocarbons." The existence of hydrocarbons correlates with petrogenesis. For example, peridotite cumulates produced by magmatic differentiation lack hydrocarbons whereas peridotite xenoliths derived from the mantle contain them. Gas Chromatographic—mass spectrometric records of the mantle hydrocarbons resemble those of aliphatics in meteorites and in petroleum. Features of the hydrocarbons are that (a) the mantle hydrocarbons reside mainly along grain boundaries and in fluid inclusions of minerals (b) heavier isoprenoids such as pristane and phytane are present (c) δ13C of the mantle hydrocarbons is uniform (about -27%.). Possible origins for the mantle hydrocarbons are as follows. (1) They were inorganically synthesized by Fischer-Tropsch type reaction in the mantle. (2) They were delivered by meteorites and comets to the early Earth. (3) They were recycled by subduction. The mantle hydrocarbons in the cases of (1) and (2) are abiogenic and those in (3) are mainly biogenic. It appears that hydrocarbons may survive high pressures and temperatures in the mantle, but they are decomposed into lighter hydrocarbon gases such as CH 4 at lower pressures when magmas intrude into the crust; consequently, peridotite cumulates do not contain heavier hydrocarbons but possess hydrocarbon gases up to C 4H 10.

  7. Model advanced for hydrocarbon microseepage, related alterations

    SciTech Connect

    Thompson, C.K. ); Saunders, D.F.; Burson, K.R. )

    1994-11-14

    Future significant petroleum fields will be found in subtle stratigraphic traps in addition to structural traps. Both may be detectable by measuring surface hydrocarbon microseepage and related alterations. Reasons these methods have not been commonly used include: (1) early over-selling by some contractors with consequent bad client experiences, and (2) lack of generally accepted scientific models to relate anomalies to subsurface hydrocarbon accumulations. This article is restricted primarily to the authors' specific experience, studies, and conclusions over some 38 years with particular emphasis on the last 15 years. The authors believe these findings have resulted in improved wildcat success rates and realistic scientific models.

  8. Catalysts for synthesizing various short chain hydrocarbons

    DOEpatents

    Colmenares, Carlos

    1991-01-01

    Method and apparatus (10), including novel photocatalysts, are disclosed for the synthesis of various short chain hydrocarbons. Light-transparent SiO.sub.2 aerogels doped with photochemically active uranyl ions (18) are fluidized in a fluidized-bed reactor (12) having a transparent window (16), by hydrogen and CO, C.sub.2 H.sub.4 or C.sub.2 H.sub.6 gas mixtures (20), and exposed to radiation (34) from a light source (32) external to the reactor (12), to produce the short chain hydrocarbons (36).

  9. Hydrocarbon disperse systems in electric fields

    SciTech Connect

    Deinega, Y.F.

    1983-07-01

    On the basis of method for regulating the smooth adjustment of the charge of the disperse phase of hydrocarbon systems in electric fields from positive to negative values by means of surfactants, a schematic electrokinetic picture of the behavior of the systems is derived. Changes in the structure of the disperse systems in electric fields have a substantial effect on the rheological properties of the system. The effect of electric fields on the formation of crystallization-condensation structures, the mechanism of electrical conduction with a high rate of deformation, and the many practical applications of electrical effects on hydrocarbon disperse systems are also studied.

  10. [Storage of hydrocarbon-degrading bacteria].

    PubMed

    Bade, G M; Vecchioli, G I; del Panno, M T; Painceira, M T

    1994-01-01

    The storage in the laboratory of hydrocarbon degrading bacteria to be used in the decontamination of polluted sites or in the enhancement of biological treatment of industrial effluents was studied. Storage was carried out at 4 degrees C in nutrient agar and in a medium with selection pressure, liquid mineral medium with hydrocarbons. Storage at 4 degrees C with selection pressure and storage at -20 degrees C of 7 gram negative bacilli were compared. The former was the easiest method for preserving the greatest number of strains viable and active. PMID:7838975

  11. Heating hydrocarbon containing formations in a line drive staged process

    DOEpatents

    Miller, David Scott

    2009-07-21

    Method for treating a hydrocarbon containing formation are described herein. Methods may include providing heat to a first section of the formation with one or more first heaters in the first section. First hydrocarbons may be heated in the first section such that at least some of the first hydrocarbons are mobilized. At least some of the mobilized first hydrocarbons may be produced through a production well located in a second section of the formation. The second section may be located substantially adjacent to the first section. A portion of the second section may be provided some heat from the mobilized first hydrocarbons, but is not conductively heated by heat from the first heaters. Heat may be provided to the second section with one or more second heaters in the second section to further heat the second section.

  12. Bacterial sources for phenylalkane hydrocarbons

    SciTech Connect

    Ellis, L.; Winans, R.E.; Langworthy, T.

    1996-10-01

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

  13. Extracting hydrocarbons from water using a centrifuge

    NASA Astrophysics Data System (ADS)

    Ryabov, A. Yu.; Ilyina, A. A.; Chuikin, A. V.; Velikov, A. A.

    2014-09-01

    An original method for the solid-phase microextraction of hydrocarbons from water using a centrifuge is proposed. Comparative results from the chromatographic elution of substances after liquid-phase and solid-phase microextraction are presented. The percentage of the extraction of substances from aqueous solutions and the minimum detection limit for aromatic and aliphatic compounds are calculated.

  14. Influence of the method of production of eggs on the daily intake of polycyclic aromatic hydrocarbons and organochlorine contaminants: an independent study in the Canary Islands (Spain).

    PubMed

    Luzardo, Octavio P; Rodríguez-Hernández, Angel; Quesada-Tacoronte, Yohana; Ruiz-Suárez, Norberto; Almeida-González, Maira; Henríquez-Hernández, Luis Alberto; Zumbado, Manuel; Boada, Luis D

    2013-10-01

    Analysis of 16 polycyclic aromatic hydrocarbons (PAHs), 20 organochlorine pesticides (OCPs) and 18 polychlorinated biphenyls (PCBs) were performed on eggs from three different production types (conventional, free-run and organic) collected from the markets of the Canary Islands (Spain). Unlike other studies we did not found differences in the content of PCBs or OCPs of eggs in relation to its production type. Median ∑OCPs content was 3.87 ng g⁻¹ fat, being dieldrin, dicofol, hexachlorobenzene, p,p'-DDE and p,p'-DDT the most frequently detected. Median ∑PCBs value was 3.93 ng g⁻¹ fat, with 79.9% of this amount coming from the marker PCBs. Two samples, one free-run and one organic, greatly exceeded the current European Commission (EC) limit of 2.5 pg TEQ(PCDD/F) g⁻¹ lipid, but the rest were well below of this limit. The concentrations of PAHs in conventionally produced eggs were almost 4 times higher than in free-run or organic eggs. Mean dietary intake estimates of the organochlorine contaminants based on consumption of eggs, regardless of the type chosen, is negligible for the Canary Islands' population. However, the median dietary intake estimates of PAHs greatly depend on the type of eggs chosen, being much lower when free-run and organic eggs are consumed. PMID:23939041

  15. Assessing Aromatic-Hydrocarbon Toxicity to Fish Early Life Stages Using Passive-Dosing Methods and Target-Lipid and Chemical-Activity Models.

    PubMed

    Butler, Josh D; Parkerton, Thomas F; Redman, Aaron D; Letinski, Daniel J; Cooper, Keith R

    2016-08-01

    Aromatic hydrocarbons (AH) are known to impair fish early life stages (ELS). However, poorly defined exposures often confound ELS-test interpretation. Passive dosing (PD) overcomes these challenges by delivering consistent, controlled exposures. The objectives of this study were to apply PD to obtain 5 d acute embryo lethality and developmental data and 30 d chronic embryo-larval survival and growth-effects data using zebrafish with different AHs; to analyze study and literature toxicity data using target-lipid (TLM) and chemical-activity (CA) models; and to extend PD to a mixture and test the assumption of AH additivity. PD maintained targeted exposures over a concentration range of 6 orders of magnitude. AH toxicity increased with log Kow up to pyrene (5.2). Pericardial edema was the most sensitive sublethal effect that often preceded embryo mortality, although some AHs did not produce developmental effects at concentrations causing mortality. Cumulative embryo-larval mortality was more sensitive than larval growth, with acute-to-chronic ratios of <10. More-hydrophobic AHs did not exhibit toxicity at aqueous saturation. The relationship and utility of the TLM-CA models for characterizing fish ELS toxicity is discussed. Application of these models indicated that concentration addition provided a conservative basis for predicting ELS effects for the mixture investigated. PMID:27398931

  16. Increased concentrations of polycyclic aromatic hydrocarbons in Alpine streams during annual snowmelt: investigating effects of sampling method, site characteristics, and meteorology.

    PubMed

    Shahpoury, Pourya; Hageman, Kimberly J; Matthaei, Christoph D; Alumbaugh, Robert E; Cook, Michelle E

    2014-10-01

    Silicone passive samplers and macroinvertebrates were used to measure time-integrated concentrations of polycyclic aromatic hydrocarbons (PAHs) in alpine streams during annual snowmelt. The three sampling sites were located near a main highway in Arthur's Pass National Park in the Southern Alps of New Zealand. A similar set of PAH congeners, composed of 2-4 rings, were found in silicone passive samplers and macroinvertebrates. The background PAH concentrations were similar at all sites, implying that proximity to the highway did not affect concentrations. In passive samplers, an increase of PAH concentrations by up to seven times was observed during snowmelt. In macroinvertebrates, the concentration changes were moderate; however, macroinvertebrate sampling did not occur during the main pulse observed in the passive samplers. The extent of vegetation in the catchment appeared to affect the concentration patterns seen at the different stream sites. A strong correlation was found between PAH concentrations in passive samplers and the amount of rainfall in the study area, indicating that the washout of contaminants from snowpack by rainfall was an important process. PMID:25153782

  17. Characterizing the transplanar and in-plane water transport of textiles with gravimetric and image analysis technique: Spontaneous Uptake Water Transport Tester

    PubMed Central

    Tang, K. P. M.; Wu, Y. S.; Chau, K. H.; Kan, C. W.; Fan, J. T.

    2015-01-01

    Water absorption and transport property of textiles is important since it affects wear comfort, efficiency of treatment and functionality of product. This paper introduces an accurate and reliable measurement tester, which is based on gravimetric and image analysis technique, for characterising the transplanar and in-plane wicking property of fabrics. The uniqueness of this instrument is that it is able to directly measure the water absorption amount in real-time, monitor the direction of water transport and estimate the amount of water left on skin when sweating. Throughout the experiment, water supply is continuous which simulates profuse sweating. Testing automation could even minimise variation caused by subjective manipulation, thus enhancing testing accuracy. This instrument is versatile in terms of the fabrics could be tested. A series of shirting fabrics made by different fabric structure and yarn were investigated and the results show that the proposed method has high sensitivity in differentiating fabrics with varying geometrical differences. Fabrics with known hydrophobicity were additionally tested to examine the sensitivity of the instrument. This instrument also demonstrates the flexibility to test on high performance moisture management fabrics and these fabrics were found to have excellent transplanar and in-plane wicking properties. PMID:25875329

  18. Characterizing the transplanar and in-plane water transport of textiles with gravimetric and image analysis technique: Spontaneous Uptake Water Transport Tester

    NASA Astrophysics Data System (ADS)

    Tang, K. P. M.; Wu, Y. S.; Chau, K. H.; Kan, C. W.; Fan, J. T.

    2015-04-01

    Water absorption and transport property of textiles is important since it affects wear comfort, efficiency of treatment and functionality of product. This paper introduces an accurate and reliable measurement tester, which is based on gravimetric and image analysis technique, for characterising the transplanar and in-plane wicking property of fabrics. The uniqueness of this instrument is that it is able to directly measure the water absorption amount in real-time, monitor the direction of water transport and estimate the amount of water left on skin when sweating. Throughout the experiment, water supply is continuous which simulates profuse sweating. Testing automation could even minimise variation caused by subjective manipulation, thus enhancing testing accuracy. This instrument is versatile in terms of the fabrics could be tested. A series of shirting fabrics made by different fabric structure and yarn were investigated and the results show that the proposed method has high sensitivity in differentiating fabrics with varying geometrical differences. Fabrics with known hydrophobicity were additionally tested to examine the sensitivity of the instrument. This instrument also demonstrates the flexibility to test on high performance moisture management fabrics and these fabrics were found to have excellent transplanar and in-plane wicking properties.

  19. Characterizing the transplanar and in-plane water transport of textiles with gravimetric and image analysis technique: Spontaneous Uptake Water Transport Tester.

    PubMed

    Tang, K P M; Wu, Y S; Chau, K H; Kan, C W; Fan, J T

    2015-01-01

    Water absorption and transport property of textiles is important since it affects wear comfort, efficiency of treatment and functionality of product. This paper introduces an accurate and reliable measurement tester, which is based on gravimetric and image analysis technique, for characterising the transplanar and in-plane wicking property of fabrics. The uniqueness of this instrument is that it is able to directly measure the water absorption amount in real-time, monitor the direction of water transport and estimate the amount of water left on skin when sweating. Throughout the experiment, water supply is continuous which simulates profuse sweating. Testing automation could even minimise variation caused by subjective manipulation, thus enhancing testing accuracy. This instrument is versatile in terms of the fabrics could be tested. A series of shirting fabrics made by different fabric structure and yarn were investigated and the results show that the proposed method has high sensitivity in differentiating fabrics with varying geometrical differences. Fabrics with known hydrophobicity were additionally tested to examine the sensitivity of the instrument. This instrument also demonstrates the flexibility to test on high performance moisture management fabrics and these fabrics were found to have excellent transplanar and in-plane wicking properties. PMID:25875329

  20. Electrochemical evaluation of the corrosion behaviour for structural steel SAE 1005 exposed to two different atmospheres (urban and industrial) and comparison with atmospheric corrosion gravimetric measurements

    NASA Astrophysics Data System (ADS)

    Salas, Y.; Guerrero, L.; Castiblanco, H.; Torres, C.; Palacios, A.

    2016-02-01

    The Atmospheric corrosion is a phenomenon we see every day in our environment that arises due to environmental pollution we generate, there is currently very little information on atmospheric corrosion in the department of Boyacá and in general, in Colombia. The aim of this paper is to analyse which of these two environments is more aggressive and wherein the steel corrodes faster. To analyse these phenomenon specimens made in steel SAE 105 exposed for five months to the atmosphere in the municipalities of Tunja and Nobsa (an urban atmosphere and other industrial atmosphere) were installed, a control was carried to verify the amount of time that will be exposed each of these samples to the atmosphere, of Thus it may determine the lifetime of a structural steel. For the analysis of these samples electrochemical tests were carried out to calculate the rate of corrosion and resistance to polarization, also the gravimetric method be conducted to compare what was the amount of mass lost during the time of exposure to each of the samples.

  1. Membrane separation of hydrocarbons

    DOEpatents

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

    1986-01-01

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

  2. Site characterization and petroleum hydrocarbon plume mapping

    SciTech Connect

    Ravishankar, K.

    1996-12-31

    This paper presents a case study of site characterization and hydrocarbon contamination plume mapping/delineation in a gas processing plant in southern Mexico. The paper describes innovative and cost-effective use of passive (non-intrusive) and active (intrusive) techniques, including the use of compound-specific analytical methods for site characterization. The techniques used, on a demonstrative basis, include geophysical, geochemical, and borehole drilling. Geochemical techniques used to delineate the horizontal extent of hydrocarbon contamination at the site include soil gas surveys. The borehole drilling technique used to assess the vertical extent of contamination and confirm geophysical and geochemical data combines conventional hollow-stem auguring with direct push-probe using Geoprobe. Compound-specific analytical methods, such as hydrocarbon fingerprinting and a modified method for gasoline range organics, demonstrate the inherent merit and need for such analyses to properly characterize a site, while revealing the limitations of noncompound-specific total petroleum hydrocarbon analysis. The results indicate that the techniques used in tandem can properly delineate the nature and extent of contamination at a site; often supplement or complement data, while reducing the risk of errors and omissions during the assessment phase; and provide data constructively to focus site-specific remediation efforts. 7 figs.

  3. FROZEN HYDROCARBONS IN COMETS

    SciTech Connect

    Simonia, Irakli

    2011-02-15

    Recent investigations of the luminescence of frozen hydrocarbon particles of icy cometary halos have been carried out. The process of luminescence of organic icy particles in a short-wavelength solar radiation field is considered. A comparative analysis of observed and laboratory data leads to 72 luminescent emission lines in the spectrum of the comet 153P/Ikeya-Zhang. The concept of cometary relict matter is presented, and the creation of a database of unidentified cometary emission lines is proposed.

  4. Direct hydrocarbon fuel cells

    DOEpatents

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

    2010-05-04

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

  5. Vmh2 hydrophobin layer entraps glucose: A quantitative characterization by label-free optical and gravimetric methods

    NASA Astrophysics Data System (ADS)

    Della Ventura, B.; Rea, I.; Caliò, A.; Giardina, P.; Gravagnuolo, A. M.; Funari, R.; Altucci, C.; Velotta, R.; De Stefano, L.

    2016-02-01

    Hydrophobins (HFBs) are peculiar proteins which self-assemble at hydrophilic-hydrophobic interfaces into amphipathic membranes, and some of them (class I HFB) are able to form much more stable amyloid-like layers. This feature makes them suitable for many purposes, particularly when stable surface functionalization is required, also in view of their versatility in binding different kinds of molecules. For instance, it has been shown that Vmh2 from Pleurotus ostreatus (a class I HFB) is able to bind molecules like glucose, thus offering the perspective of using Vmh2 as a surface functionalization tool in bio-hybrid devices. In this paper a quantitative analysis of glucose interaction with the Vmh2 layer is reported; in particular, it is shown that Vmh2 layer swells by almost doubling its thickness as a result of glucose diffusion and each Vmh2 monomer is able to bind approximately 30 glucose molecules. These results have been achieved by self-assembling multi-layers of Vmh2 on a gold substrate and, subsequently, measuring both the mass of the bound glucose and the thickness of the resulting layer through two different and complementary techniques: quartz crystal-microbalance and ellipsometry. The data provided by the two techniques are in a satisfactory agreement and offer a plausible description of the mechanisms underlying the interaction of glucose with Vmh2 layer. This facile and versatile coating is of interest for biomedical applications of gold surfaces and particles.

  6. Li{sub 4}FeH{sub 6}: Iron-containing complex hydride with high gravimetric hydrogen density

    SciTech Connect

    Saitoh, Hiroyuki; Takagi, Shigeyuki; Matsuo, Motoaki; Aoki, Katsutoshi; Iijima, Yuki; Endo, Naruki; Orimo, Shin-ichi

    2014-07-01

    Li{sub 4}FeH{sub 6}, which has the highest gravimetric hydrogen density of iron-containing complex hydrides reported so far, is synthesized by hydrogenation of a powder mixture of iron and LiH above 6.1 GPa at 900 °C. In situ synchrotron radiation X-ray diffraction measurements reveal that while kinetics require high temperature and thus high pressure for the synthesis, Li{sub 4}FeH{sub 6} is expected to be thermodynamically stable slightly below room temperature at ambient pressure; further synthetic studies to suppress the kinetic effects may enable us to synthesize Li{sub 4}FeH{sub 6} at moderate pressures. Li{sub 4}FeH{sub 6} can be recovered at ambient conditions where Li{sub 4}FeH{sub 6} is metastable.

  7. Application of gamma-ray radiography and gravimetric measurements after accelerated corrosion tests of steel embedded in mortar

    SciTech Connect

    Duffó, Gustavo; Gaillard, Natalia; Mariscotti, Mario; Ruffolo, Marcelo

    2015-08-15

    The accelerated corrosion by the impressed current technique is widely used in studies of concrete durability since it has the advantage that tests can be carried out within reasonable periods of time. In the present work the relationship between the applied current density and the resulting damage on the reinforcing steel, by applying optical microscopy, scanning electron microscopy, gamma-ray radiography and gravimetric measurements, was studied by means of the implementation of accelerated corrosion tests on reinforced mortar. The results show that the efficiency of the applied current is between 1 and 77%, regardless of the applied current density, the water/cement ratio and the mortar cover depth of the specimens. The results show the applicability of the gamma-ray radiography technique to detect localized corrosion of steel rebars in laboratory specimens.

  8. Evaluation of gravimetric ground truth soil moisture data collected for the agricultural soil moisture experiment, 1978 Colby, Kansas, aircraft mission

    NASA Technical Reports Server (NTRS)

    Arya, L. M.; Phinney, D. E. (Principal Investigator)

    1980-01-01

    Soil moisture data acquired to support the development of algorithms for estimating surface soil moisture from remotely sensed backscattering of microwaves from ground surfaces are presented. Aspects of field uniformity and variability of gravimetric soil moisture measurements are discussed. Moisture distribution patterns are illustrated by frequency distributions and contour plots. Standard deviations and coefficients of variation relative to degree of wetness and agronomic features of the fields are examined. Influence of sampling depth on observed moisture content an variability are indicated. For the various sets of measurements, soil moisture values that appear as outliers are flagged. The distribution and legal descriptions of the test fields are included along with examinations of soil types, agronomic features, and sampling plan. Bulk density data for experimental fields are appended, should analyses involving volumetric moisture content be of interest to the users of data in this report.

  9. Electromagnetic, magnetic, and gravimetric surveys at the Bi'r Jarbuah gold prospect, Kingdom of Saudi Arabia

    USGS Publications Warehouse

    Miller, C.H.; Showail, A.A.; Bazzari, M.A.; Khoja, J.A.; Hajour, M.O.

    1990-01-01

    A detailed search for gold and associated minerals was begun in the Bi'r Jarbuah area in 1988. Crone electromagnetic (CEM), magnetic, and gravimetric surveys were run in the areas of greatest interest. Anomalous areas are most interesting in the southern part of the area where linear magnetic and gravity anomalies trend east-northeast and overlap in large part. They are most prominent at or near the south end of a diorite pluton where some quartz veins mined by the ancients also trend northeast. A second area, at the extreme southern end of the survey, contains a large CEM anomaly that coincides with northeast-trending magnetic and gravity anomalies. Although this second area is largely overlain by alluvium, a major quartz vein strikes to the northeast in the adjacent bedrock.

  10. Detailed geoid computations for GEOS-C altimeter experiment areas. [gravimetric geoid for Atlantic and northeast Pacific Ocean areas

    NASA Technical Reports Server (NTRS)

    Marsh, J. G.; Vincent, S.

    1973-01-01

    The GEOS-C spacecraft is scheduled to carry onboard a radar altimeter for the purpose of measuring the geoid undulations in oceanic areas. An independently derived geoid map will provide a valuable complement to these experiments. A detailed gravimetric geoid is presented for the Atlantic and northeast Pacific Ocean areas based upon a combination of the Goddard Space Flight Center GEM-6 earth model and surface 1 deg x 1 deg gravity data. As part of this work a number of satellite derived gravity models were evaluated to establish the model which best represented the long wave length features of the geoid in the above mentioned area. Comparisons of the detailed geoid with the astrogeodetic data provided by the National Ocean Survey and dynamically derived tracking station heights indicate that the accuracy of this combined geoid is on the order of 2 meters or better where data was dense and 5 to 7 meters where data was less dense.

  11. The Deep Structure of the South Atlantic Kwanza Basin - Insights from 3D Structural and Gravimetric modelling

    NASA Astrophysics Data System (ADS)

    Nicolai, Christina V.; Scheck-Wenderoth, Magdalena; Warsitzka, Michael

    2010-05-01

    Three dimensional geological models constrained by potential field data have proven to be powerful tools for the investigation of areas where conventional seismic surveying fails to deliver satisfactory results. Especially in basins containing thick sedimentary and/or evaporite layers, the detection of crustal structures such as synrift halfgrabens or basement highs is considerably enhanced by potential field data. Knowledge on the distribution and configuration of crustal structures is inalienable for the reconstruction of the tectonic history of a continental margin. In this study, we present results from 3D gravimetric modelling of the Kwanza Basin offshore Angola accomplished to investigate the formation of the basin in response to the opening of the South Atlantic. Although the post-rift evolution of the Kwanza Basin is well studied, little is known about the basins early history. This is mainly due to the missing knowledge of its crustal structure owing to the masking effect of an up to 3 km thick salt layer, which seismically obscures the underlying basement. To get an insight into the deeper structure of the Angolan margin we combined 3D structural, isostatic and gravimetric modelling. 2D seismic reflection data was used to determine the structural setting and the configuration of the stratigraphic units in the sedimentary part of the basin, whereas its crustal structure was constrained by isostatic and gravity modelling. The resulting geological model confirms and extends previous observations, and adds new details to the hitherto dim picture of the Kwanza Basins crustal architecture. In addition, it raises new questions on the volcanic or non-volcanic origin of the margin, and the potential of transfer faults to dissect the latter into independently evolving tectonic segments.

  12. Radical scavengers from heavy hydrocarbons

    SciTech Connect

    Kubo, Junichi

    1996-10-01

    The hydrogen-donating properties of some hydrocarbons form the basis for processes such as coal liquefaction and heavy oil upgrading. However, these hydrocarbons have seldom been used for other purposes, because their potential applications have not been well recognized. Research has indicated that these hydrogen-donating hydrocarbons can be used in important reactions as radical scavengers and have properties particular to those of pure hydrocarbons without functional groups containing heteroatoms. Over years of study researchers have found that pure hydrocarbons with radical-scavenging effects nearly as high as those in conventional hindered phenolic antioxidants can be produced from petroleum, and these hydrogen-donating hydrocarbons exhibit such effects even in oxidative atmospheres (i.e., they function as antioxidants). He has also shown that these mixtures have some properties particular to pure hydrocarbons without functional groups containing heteroatoms, and they`ve seen that a mechanism based on the steric effects appears when these hydrocarbons are used in heavy oil hydroprocessing. Hydrogen-donating hydrocarbons should be a viable resource in many applications. In this article, he presents radical-scavenging abilities, characteristics as pure hydrocarbons, and applications on the basis of the studies.

  13. A validated liquid chromatographic method for the determination of polycyclic aromatic hydrocarbons in honey after homogeneous liquid-liquid extraction using hydrophilic acetonitrile and sodium chloride as mass separating agent.

    PubMed

    Koltsakidou, Anastasia; Zacharis, Constantinos K; Fytianos, Konstantinos

    2015-01-16

    In the present report, a simple and cost-effective method for the determination of twelve US EPA priority polycyclic aromatic hydrocarbons (PAHs) in honey samples after salting-assisted liquid-liquid extraction and UHPLC with fluorescence detection is proposed. The sample treatment is based on the usage of hydrophilic acetonitrile as extraction solvent and its phase separation under high salinity conditions. Due to the high sugar content of the samples the phase separation is promoted effortlessly. Several parameters affecting the extraction efficiency and method sensitivity including the concentration of the honey samples, the type and volume of the extraction solvent, the type and quantity of the inorganic salt, extraction time and centrifugation time was systematically investigated. The method was validated in-house according to the Commission Decision 2002/657/EC guidelines. The limit of detection (LOD) of the method lay between 0.02 and 0.04ngmL(-1) (corresponding to 0.08 and 0.16ngg(-1)) which are close to the quality criteria established by European Regulation (EC) 836/2011 concerning the PAHs in foodstuffs. The mean analytical bias (expressed as relative recoveries) in all spiking levels was acceptable being in the range of 54-118% while the relative standard deviation (RSD) was lower than 19%. The proposed method has been satisfactorily applied for the analysis of the selected PAHs residues in various honey samples obtained from Greek region. PMID:25543304

  14. Integral Approaches to Determine Sub-Crustal Stress from Terrestrial Gravimetric Data

    NASA Astrophysics Data System (ADS)

    Eshagh, Mehdi

    2016-03-01

    The spherical harmonic expressions of the horizontal sub-crustal stress components induced by the mantle convection are convergent only to low degrees. In this paper, we use the method of stress (S) function with numerical differentiation and present a formula for determining the degree of convergence from the mean Moho depth. We found that for the global mean Moho depth, 23 km, this convergence degree is 622 and for Iran, 35 km, it is 372. Also, three methods are developed and applied for computing the sub-crustal stress, (1) direct integration with a spectral kernel limited up to the degree of convergence, (2) integral inversion with a kernel having closed-form formula without any frequency limit, and (3) solving an integral equation with limited spectral kernel to the convergence degree. The second method has no divergence problem and its kernel function is well behaving so that the system of equations from which the S function is determined is stable, and no regularisation is needed to solve it. It should be noted that for using this method the resolution of the recovery should be higher than 0.5° × 0.5°, otherwise the recovered S function and correspondingly the stress components will have smaller magnitude than those derived from the other two methods. Our numerical studies for stress recovery in Iran and its surrounding areas show that the methods, which use the limited spectral kernels to the convergence degree, deliver consistent results to that of the spherical harmonic expansion.

  15. Determination of Total Petroleum Hydrocarbons (TPH) Using Total Carbon Analysis

    SciTech Connect

    Ekechukwu, A.A.

    2002-05-10

    Several methods have been proposed to replace the Freon(TM)-extraction method to determine total petroleum hydrocarbon (TPH) content. For reasons of cost, sensitivity, precision, or simplicity, none of the replacement methods are feasible for analysis of radioactive samples at our facility. We have developed a method to measure total petroleum hydrocarbon content in aqueous sample matrixes using total organic carbon (total carbon) determination. The total carbon content (TC1) of the sample is measured using a total organic carbon analyzer. The sample is then contacted with a small volume of non-pokar solvent to extract the total petroleum hydrocarbons. The total carbon content of the resultant aqueous phase of the extracted sample (TC2) is measured. Total petroleum hydrocarbon content is calculated (TPH = TC1-TC2). The resultant data are consistent with results obtained using Freon(TM) extraction followed by infrared absorbance.

  16. Chromatographic detection and analysis of traces of hydrocarbons

    NASA Technical Reports Server (NTRS)

    Fickey, E. W.; Mullins, H. E.

    1969-01-01

    Special analytical column having in series two separate absorption sections charged with beads of porous polymer and a sample of gas detects traces of hydrocarbons. New method requires only 15 minutes for execution.

  17. NATURAL HYDROCARBON EMISSION RATE MEASUREMENTS FROM SELECTED FOREST SITES

    EPA Science Inventory

    The report presents results from studies of biogenic hydrocarbon emissions conducted in Lancaster, Pennsylvania during 1979 and Seattle, Washington during 1980. The principal objective of the studies was to compare a branch enclosure method with a micrometeorological gradient tec...

  18. Prediction of Transport Properties of Permeants through Polymer Films. A Simple Gravimetric Experiment.

    ERIC Educational Resources Information Center

    Britton, L. N.; And Others

    1988-01-01

    Considers the applicability of the simple emersion/weight-gain method for predicting diffusion coefficients, solubilities, and permeation rates of chemicals in polymers that do not undergo physical and chemical deterioration. Presents the theoretical background, procedures and typical results related to this activity. (CW)

  19. Analysis of hydrocarbons generated in coalbeds

    NASA Astrophysics Data System (ADS)

    Butala, Steven John M.

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

  20. Volatile hydrocarbons and fuel oxygenates: Chapter 12

    USGS Publications Warehouse

    Cozzarelli, Isabelle M.

    2014-01-01

    Petroleum hydrocarbons and fuel oxygenates are among the most commonly occurring and widely distributed contaminants in the environment. This chapter presents a summary of the sources, transport, fate, and remediation of volatile fuel hydrocarbons and fuel additives in the environment. Much research has focused on the transport and transformation processes of petroleum hydrocarbons and fuel oxygenates, such as benzene, toluene, ethylbenzene, and xylenes and methyl tert‐butyl ether, in groundwater following release from underground storage tanks. Natural attenuation from biodegradation limits the movement of these contaminants and has received considerable attention as an environmental restoration option. This chapter summarizes approaches to environmental restoration, including those that rely on natural attenuation, and also engineered or enhanced remediation. Researchers are increasingly combining several microbial and molecular-based methods to give a complete picture of biodegradation potential and occurrence at contaminated field sites. New insights into the fate of petroleum hydrocarbons and fuel additives have been gained by recent advances in analytical tools and approaches, including stable isotope fractionation, analysis of metabolic intermediates, and direct microbial evidence. However, development of long-term detailed monitoring programs is required to further develop conceptual models of natural attenuation and increase our understanding of the behavior of contaminant mixtures in the subsurface.

  1. Chemical contamination and transformation of soils in hydrocarbon production regions

    NASA Astrophysics Data System (ADS)

    Zamotaev, I. V.; Ivanov, I. V.; Mikheev, P. V.; Nikonova, A. N.

    2015-12-01

    The current concepts of soil pollution and transformation in the regions of hydrocarbon production have been reviewed. The development of an oil field creates extreme conditions for pedogenesis. Tendencies in the radial migration, spatial distribution, metabolism, and accumulation of pollutants (oil, oil products, and attendant heavy metals) in soils of different bioclimatic zones have been analyzed. The radial and lateral mobility of pollution halos is a universal tendency in the technogenic transformation of soils and soil cover in the regions of hydrocarbon production. The biodegradation time of different hydrocarbon compounds strongly varies under different landscape conditions, from several months to several tens of years. The transformation of original (mineral and organic) soils to their technogenic modifications (mechanically disturbed, chemically contaminated, and chemo soils and chemozems) occurs in the impact zone of technogenic hydrocarbon fluxes under any physiographical conditions. The integrated use of the existing methods for the determination of the total content and qualitative composition of bituminous substances and polyaromatic hydrocarbons in combination with the chromatographic determination of normal alkanes and hydrocarbon gases, as well as innovative methods of studies, allows revealing new processes and genetic relationships in soils and studying the functioning of soils and soil cover. The study of the hydrocarbon contamination of soils is important for development of restoration measures and lays the groundwork for the ecological and hygienic regulation based on the zonation of soil and landscape resistance to different pollutants.

  2. Process for separating an ethylenically unsaturated hydrocarbon from a hydrocarbon mixture

    SciTech Connect

    vanEijl, A.T.

    1986-06-24

    A process is described for separating an ethylenically unsaturated hydrocarbon from a hydrocarbon mixture characterized by: (a) distilling a hydrocarbon mixture containing the unsaturated hydrocarbon with an N-(aminoalkyl) piperazine; and (b) separating the amine/hydrocarbon mixture into at least two factions, one of which contains the amine and the unsaturated hydrocarbon.

  3. Moving hydrocarbons through portions of tar sands formations with a fluid

    DOEpatents

    Stegemeier, George Leo; Mudunuri, Ramesh Raju; Vinegar, Harold J.; Karanikas, John Michael; Jaiswal, Namit; Mo, Weijian

    2010-05-18

    A method for treating a tar sands formation is disclosed. The method includes heating a first portion of a hydrocarbon layer in the formation from one or more heaters located in the first portion. The heat is controlled to increase a fluid injectivity of the first portion. A drive fluid and/or an oxidizing fluid is injected and/or created in the first portion to cause at least some hydrocarbons to move from a second portion of the hydrocarbon layer to a third portion of the hydrocarbon layer. The second portion is between the first portion and the third portion. The first, second, and third portions are horizontally displaced from each other. The third portion is heated from one or more heaters located in the third portion. Hydrocarbons are produced from the third portion of the formation. The hydrocarbons include at least some hydrocarbons from the second portion of the formation.

  4. Azeotropic distillation process for recovery of diamondoid compounds from hydrocarbon streams

    SciTech Connect

    Alexander, R.A.; Whitehurst, D.D.

    1992-08-18

    This patent describes a method for separating a diamondoid compound selected from the group consisting of adamantane, diamantane, triamantane and the alkyl substituted homologs of adamantane, diamantane, and triamantane from a hydrocarbon compound. This patent also describes a method for extracting diamondoid compounds from a hydrocarbon gas containing the same. It comprises providing a hydrocarbon gas stream containing a recoverable concentration of at least one concentration of at least one diamondoid compound; contacting the hydrocarbon gas stream with a liquid hydrocarbon solvent in which the diamondoid compound is at least partially soluble to dissolve the diamondoid compound in the liquid hydrocarbon solvent; and distilling the diamondoid-containing hydrocarbon solvent of step in the presence of water sufficient to cause an azeotrope with the diamondoid compound.

  5. IDENTIFYING THE SIGNATURE OF THE NATURAL ATTENUATION IN THE MICROBIAL ECOLOGY OF HYDROCARBON CONTAMINATED GROUNDWATER USING MOLECULAR METHODS AND &LDQUO;BUG TRAPS&RDQUO;

    EPA Science Inventory

    These related projects have combined biological molecular methods and a novel passive sampling system (bio-trap) to produce a technology that will allow the active component of any contaminated groundwater microbial community to be investigated. Conventional sampling methods c...

  6. Comparative study for determination of some polycyclic aromatic hydrocarbons ‘PAHs' by a new spectrophotometric method and multivariate calibration coupled with dispersive liquid-liquid extraction

    NASA Astrophysics Data System (ADS)

    Abdel-Aziz, Omar; El Kosasy, A. M.; El-Sayed Okeil, S. M.

    2014-12-01

    A modified dispersive liquid-liquid extraction (DLLE) procedure coupled with spectrophotometric techniques was adopted for simultaneous determination of naphthalene, anthracene, benzo(a)pyrene, alpha-naphthol and beta-naphthol in water samples. Two different methods were used, partial least-squares (PLS) method and a new derivative ratio method, namely extended derivative ratio (EDR). A PLS-2 model was established for simultaneous determination of the studied pollutants in methanol, by using twenty mixtures as calibration set and five mixtures as validation set. Also, in methanol a novel (EDR) method was developed for determination of the studied pollutants, where each component in the mixture of the five PAHs was determined by using a mixture of the other four components as divisor. Chemometric and EDR methods could be also adopted for determination of the studied PAH in water samples after transferring them from aqueous medium to the organic one by utilizing dispersive liquid-liquid extraction technique, where different parameters were investigated using a full factorial design. Both methods were compared and the proposed method was validated according to ICH guidelines and successfully applied to determine these PAHs simultaneously in spiked water samples, where satisfactory results were obtained. All the results obtained agreed with those of published methods, where no significant difference was observed.

  7. Process for extracting hydrocarbons from hydrocarbon bearing ores

    SciTech Connect

    Friedman, R.H.; Eakin, B.E.

    1986-02-18

    This patent describes a process for recovering hydrocarbons from a diatomite ore consisting of: reducing the size of the ore to less than about 5 mesh to form a reduced ore; combining the reduced ore with liquid to form ore pellets; treating the ore pellets to form extractable ore pellets; contacting a bed of the extractable pellets with extracting solvent in an extraction zone such that the relative velocity of the solvent to the extractable pellets is at least about one-half gallon per square foot per minute or more to thereby extract hydrocarbons from the extractable pellets and form spent pellets and a hydrocarbon rich solvent stream comprising extracting solvent and extracted hydrocarbons. The extracted hydrocarbons have an ash content of about less than 3 weight percent; and recovering extracting solvent from the spent pellets while retaining the spent pellets in pellet form without release of a significant amount of fines.

  8. Label-Free Glucose Detection Using Cantilever Sensor Technology Based on Gravimetric Detection Principles

    PubMed Central

    Hsieh, Chiung-wen; Lin, Po-Chiao

    2013-01-01

    Efficient maintenance of glucose homeostasis is a major challenge in diabetes therapy, where accurate and reliable glucose level detection is required. Though several methods are currently used, these suffer from impaired response and often unpredictable drift, making them unsuitable for long-term therapeutic practice. In this study, we demonstrate a method that uses a functionalized atomic force microscope (AFM) cantilever as the sensor for reliable glucose detection with sufficient sensitivity and selectivity for clinical use. We first modified the AFM tip with aminopropylsilatrane (APS) and then adsorbed glucose-specific lectin concanavalin A (Con A) onto the surface. The Con A/APS-modified probes were then used to detect glucose by monitoring shifts in the cantilever resonance frequency. To confirm the molecule-specific interaction, AFM topographical images were acquired of identically treated silicon substrates which indicated a specific attachment for glucose-Con A and not for galactose-Con A. These results demonstrate that by monitoring the frequency shift of the AFM cantilever, this sensing system can detect the interaction between Con A and glucose, one of the biomolecule recognition processes, and may assist in the detection and mass quantification of glucose for clinical applications with very high sensitivity. PMID:23984191

  9. A primer on liquid hydrocarbon storage in salt formations

    SciTech Connect

    Halfast, T.G.

    1996-09-01

    Storage caverns leached in both domal and bedded salt formations have been an economical, safe and environmentally sound method of storing large quantities of liquid hydrocarbons since the late 1940`s and today these formations are utilized throughout the world to store many different liquid hydrocarbons. This paper addresses some of the many factors that should be considered in the design and operation of a liquid hydrocarbon storage well. For anyone interested in a more thorough primer the author recommends obtaining copies of either API-RP-1114, Titled ``Leached Underground Storage Design`` or API-RP-1115, Titled ``Operation of Solution Mined Storage.``

  10. Comparison between light scattering and gravimetric samplers for PM10 mass concentration in poultry and pig houses

    NASA Astrophysics Data System (ADS)

    Cambra-López, María; Winkel, Albert; Mosquera, Julio; Ogink, Nico W. M.; Aarnink, André J. A.

    2015-06-01

    The objective of this study was to compare co-located real-time light scattering devices and equivalent gravimetric samplers in poultry and pig houses for PM10 mass concentration, and to develop animal-specific calibration factors for light scattering samplers. These results will contribute to evaluate the comparability of different sampling instruments for PM10 concentrations. Paired DustTrak light scattering device (DustTrak aerosol monitor, TSI, U.S.) and PM10 gravimetric cyclone sampler were used for measuring PM10 mass concentrations during 24 h periods (from noon to noon) inside animal houses. Sampling was conducted in 32 animal houses in the Netherlands, including broilers, broiler breeders, layers in floor and in aviary system, turkeys, piglets, growing-finishing pigs in traditional and low emission housing with dry and liquid feed, and sows in individual and group housing. A total of 119 pairs of 24 h measurements (55 for poultry and 64 for pigs) were recorded and analyzed using linear regression analysis. Deviations between samplers were calculated and discussed. In poultry, cyclone sampler and DustTrak data fitted well to a linear regression, with a regression coefficient equal to 0.41, an intercept of 0.16 mg m-3 and a correlation coefficient of 0.91 (excluding turkeys). Results in turkeys showed a regression coefficient equal to 1.1 (P = 0.49), an intercept of 0.06 mg m-3 (P < 0.0001) and a correlation coefficient of 0.98. In pigs, we found a regression coefficient equal to 0.61, an intercept of 0.05 mg m-3 and a correlation coefficient of 0.84. Measured PM10 concentrations using DustTraks were clearly underestimated (approx. by a factor 2) in both poultry and pig housing systems compared with cyclone pre-separators. Absolute, relative, and random deviations increased with concentration. DustTrak light scattering devices should be self-calibrated to investigate PM10 mass concentrations accurately in animal houses. We recommend linear regression

  11. A liquid chromatography/tandem mass spectrometry (LC-MS/MS) method for the determination of phenolic polycyclic aromatic hydrocarbons (OH-PAH) in urine of non-smokers and smokers.

    PubMed

    Ramsauer, Bernhard; Sterz, Katharina; Hagedorn, Heinz-Werner; Engl, Johannes; Scherer, Gerhard; McEwan, Mike; Errington, Graham; Shepperd, Jim; Cheung, Francis

    2011-01-01

    Polycyclic aromatic hydrocarbons (PAH) are products of the incomplete combustion of organic materials and, therefore, occur ubiquitously in the environment and also in tobacco smoke. Since some PAH have been classified as carcinogens, it is important to have access to suitable analytical methods for biomarkers of exposure to this class of compounds. Past experience has shown that measuring a profile of PAH metabolites is more informative than metabolites of a single PAH. Assessment of environmental and smoking-related exposure levels requires analytical methods with high sensitivity and specificity. In addition, these methods should be fast enough to allow high throughput. With these pre-conditions in mind, we developed and validated a high-performance liquid chromatographic method with tandem mass spectrometric detection (LC-MS/MS) for the determination of phenolic metabolites of naphthalene, fluorene, phenanthrene and pyrene in urine of smokers and non-smokers. Sample work-up comprised enzymatic hydrolysis of urinary conjugates and solid-phase extraction on C18 cartridges. The method showed good specificity, sensitivity, and accuracy for the intended purpose and was also sufficiently rapid with a sample throughput of about 350 per week. Application to urine samples of 100 smokers and 50 non-smokers showed significant differences between both groups for all measured PAH metabolites, and strong correlations with markers of daily smoke exposure in smoker urine. Urinary levels were in good agreement with previously reported data using different methodologies. In conclusion, the developed LC-MS/MS method is suitable for the quantification of phenolic PAH metabolites of naphthalene, fluorene, phenanthrene, and pyrene in smoker and non-smoker urine. PMID:21046075

  12. Field test of a generic method for halogenated hydrocarbons: Semivost test at an agricultural chemical manufacturing facility (May 1997). Final report, June 1994-June 1995

    SciTech Connect

    Bursey, J.T.; McGaughey, J.F.; Merrill, R.G.

    1997-05-01

    A field evaluation study was conducted for the halogenated semivolatile organic compounds listed in Title III of the Clean Air Act Amendments of 1990 that may be sampled and analyzed by the SemiVOST method. Dynamic spiking techniques were applied in the field, using a sampling strategy statistically designed to meet the requirements of EPA Method 301 for method evaluation. The second field test provided insufficient valid SemiVOST data to allow thorough statistical evaluation of the results because of problems encountered in the preparation of the samples for analysis. A protocol to address SemiVOST sample preparation was written (Draft Method 3542) and this new sample preparation protocol was applied to this field evaluation to improve compound recovery and precision.

  13. The stability and utility of diagnostic ratio hydrocarbon fingerprinting for soils contaminated with petroleum hydrocarbons

    SciTech Connect

    Douglas, G.S.; Sara McMillen

    1996-12-31

    In order to recover costs for oil spill cleanup and restoration regulatory agencies and trustees of natural resources are interested in identifying parties responsible for hydrocarbon releases, and for associated environmental damages. Chemical analyses of contaminated soil and groundwater samples are currently used to identify the sources of contamination in soil and groundwater systems. However, conventional hydrocarbon fingerprinting approaches such as EPA Method 8015, EPA Method 8270, and ASTM Method 3328-91 afford a low resolution fingerprint that is easily degraded in the environment. The challenge to the hydrocarbon chemist is to develop an analytical approach that minimizes the impact of environmental weathering and biodegradation on the oil signature and improves the accuracy of oil source identification. An advanced chemical fingerprinting strategy is presented that combines sensitive and hydrocarbon specific analytical methods with a detailed interpretive strategy designed to minimize the impacts of environmental weathering and biodegradation. Data will be presented from a series of oil biodegradation studies in soil that clearly demonstrate the utility and stability of source ratio analysis over a wide range of oil degradation states and oil types. Using principal component analysis, stable source ratios of C{sub 3}-dibenzothiophenes/C{sub 3}-phenanthrenes, and C{sub 2}-dibenzothiophenes/C{sub 2}-phenanthrenes were identified and evaluated. These source ratios retain their characteristic source ratio signature even after 95 percent of the PAH and dibenzothiophene target analytes and 70 percent of the total oil has been biodegraded.

  14. The stability and utility of diagnostic ratio hydrocarbon fingerprinting for soils contaminated with petroleum hydrocarbons

    SciTech Connect

    Douglas, G.S.; Sara McMillen

    1996-01-01

    In order to recover costs for oil spill cleanup and restoration regulatory agencies and trustees of natural resources are interested in identifying parties responsible for hydrocarbon releases, and for associated environmental damages. Chemical analyses of contaminated soil and groundwater samples are currently used to identify the sources of contamination in soil and groundwater systems. However, conventional hydrocarbon fingerprinting approaches such as EPA Method 8015, EPA Method 8270, and ASTM Method 3328-91 afford a low resolution fingerprint that is easily degraded in the environment. The challenge to the hydrocarbon chemist is to develop an analytical approach that minimizes the impact of environmental weathering and biodegradation on the oil signature and improves the accuracy of oil source identification. An advanced chemical fingerprinting strategy is presented that combines sensitive and hydrocarbon specific analytical methods with a detailed interpretive strategy designed to minimize the impacts of environmental weathering and biodegradation. Data will be presented from a series of oil biodegradation studies in soil that clearly demonstrate the utility and stability of source ratio analysis over a wide range of oil degradation states and oil types. Using principal component analysis, stable source ratios of C[sub 3]-dibenzothiophenes/C[sub 3]-phenanthrenes, and C[sub 2]-dibenzothiophenes/C[sub 2]-phenanthrenes were identified and evaluated. These source ratios retain their characteristic source ratio signature even after 95 percent of the PAH and dibenzothiophene target analytes and 70 percent of the total oil has been biodegraded.

  15. Thermophysical Properties of Hydrocarbon Mixtures

    National Institute of Standards and Technology Data Gateway

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

  16. Volatile Hydrocarbon Pheromones from Beetles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter reviews literature about hydrocarbons from beetles that serve as long-range pheromones. The most thoroughly studied beetles that use volatile hydrocarbon pheromones belong to the family Nitidulidae in the genera Carpophilus and Colopterus. Published pheromone research deals with behav...

  17. Biomonitoring method for the determination of polycyclic aromatic hydrocarbons in hair by online in-tube solid-phase microextraction coupled with high performance liquid chromatography and fluorescence detection.

    PubMed

    Yamamoto, Yusuke; Ishizaki, Atsushi; Kataoka, Hiroyuki

    2015-09-01

    Polycyclic aromatic hydrocarbons (PAHs) are formed from the incomplete combustion or pyrolysis of organic matter during industrial processing and various human activities, but human exposure to PAHs has not yet been elucidated in detail. To assess long-term exposure to PAHs, we developed a simple and sensitive method for measuring PAHs in hair by online in-tube solid-phase microextraction using a CP-Sil 19CB capillary column as an extraction device, followed by high-performance liquid chromatography using a Zorbax Eclipse PAH column and fluorescence detection. Seventeen PAHs could be analyzed simultaneously, with good linearity from 20 to 1000pg/mL each as determined using stable isotope-labeled PAH internal standards. The detection limits of PAHs were 0.5-20.4pg/mL. PAHs in human hair samples were extracted by ultrasonication in 50mM NaOH in methanol, and successfully analyzed without any interference peaks, with good recovery rates above 70% in spiked hair samples. Using this method, we evaluated the suitability of using hair PAHs as biomarkers for long-term exposure. PMID:26245363

  18. A novel headspace solid-phase microextraction method using in situ derivatization and a diethoxydiphenylsilane fibre for the gas chromatography-mass spectrometry determination of urinary hydroxy polycyclic aromatic hydrocarbons.

    PubMed

    Mattarozzi, M; Musci, M; Careri, M; Mangia, A; Fustinoni, S; Campo, L; Bianchi, F

    2009-07-24

    An innovative and simple headspace solid-phase microextraction method using a novel diethoxydiphenylsilane fibre based on in situ derivatization with acetic anhydride was optimized and validated for the gas chromatography-mass spectrometry determination of some monohydroxy metabolites of polycyclic aromatic hydrocarbons, namely 1-hydroxynaphthalene, 2-hydroxynaphtalene, 9-hydroxyfluorene, 2-hydroxyfluorene and 1-hydroxypyrene at trace levels in human urine. Enzymatic hydrolysis was applied before derivatization, whereas extraction conditions, i.e. the effects of time and temperature of extraction and salt addition were investigated by experimental design. Regression models and desirability functions were applied to find the experimental conditions providing the highest global extraction response. These conditions were found in correspondence of an extraction temperature of 90 degrees C, an extraction time of 90 min and 25% NaCl added to urine samples. The capabilities of the developed method were proved obtaining limit of quantitations in the 0.1-2 microg/l range, thus allowing the bio-monitoring of these compounds in human urine. A good precision was observed both in terms of intra-batch and inter-batch repeatability with RSD always lower than 14%. Recoveries ranging from 98(+/-3) to 121(+/-1)% and extraction yields higher than 72% were also obtained. Finally, the analysis of urine specimens of coke-oven workers revealed analytes' concentrations in the 2.2-164 microg/l range, proving the exposure to PAHs of the involved workers. PMID:19523642

  19. Hydrocarbon sensors and materials therefor

    DOEpatents

    Pham, Ai Quoc; Glass, Robert S.

    2000-01-01

    An electrochemical hydrocarbon sensor and materials for use in sensors. A suitable proton conducting electrolyte and catalytic materials have been found for specific application in the detection and measurement of non-methane hydrocarbons. The sensor comprises a proton conducting electrolyte sandwiched between two electrodes. At least one of the electrodes is covered with a hydrocarbon decomposition catalyst. Two different modes of operation for the hydrocarbon sensors can be used: equilibrium versus non-equilibrium measurements and differential catalytic. The sensor has particular application for on-board monitoring of automobile exhaust gases to evaluate the performance of catalytic converters. In addition, the sensor can be utilized in monitoring any process where hydrocarbons are exhausted, for instance, industrial power plants. The sensor is low cost, rugged, sensitive, simple to fabricate, miniature, and does not suffer cross sensitivities.

  20. Diterpenoid tetracyclic hydrocarbons of petroleum

    SciTech Connect

    Vorob'eva, N.S.; Zemskova, Z.K.; Pekh, T.I.; Petrov, A.A.

    1987-08-01

    Diterpenoid hydrocarbons are fairly widespread in various caustobioliths. However, if petroleums contain mainly acyclic diterpenoids (phytane, pristane and norpristane), cyclic diterpaenes such as fichtelite, pimarane, iosene (kaurane) and hibbane are often found in hydrocarbons isolated from coal and shale. Recent advances in the chemistry of diterpenoids isolated from caustobioliths, are described in a separate paper. Much less is known about petroleum polycyclic diterpenoid hydrocarbons, particularly those with four saturated rings. A series of tetracyclic hydrocarbons C/sub 19/H/sub 32/ (molar mass 260), found in a number of light petroleums and gas condensates from the Jura deposits of Central Kara-Kum (Turkmen S.S.R.), are examined here. These hydrocarbons are present in petroleums and condensates from the Davaly, Erden, Ortakak, Southern Beuideshik deposits, they are always identical and occur in the same ratios. The composition of the tretracyclanes isolated from the Ortakak gas condensates (well 17) will be examined in detail.

  1. Gravimetric evidences of active faults and underground structure of the Cheliff seismogenic basin (Algeria)

    NASA Astrophysics Data System (ADS)

    Abtout, A.; Boukerbout, H.; Bouyahiaoui, B.; Gibert, D.

    2014-11-01

    The Cheliff basin (ex El Asnam) is known as one of the most seismic active zone in Algeria and the West Mediterranean region. We can cite the El Asnam earthquake which occurred in 10.10.01980 with magnitude of 7.3. It was generated by a thrust fault with NE-SW sinistral component. Until now, there is a little information about existence of deep active faults, which generate this strong activity. The gravity field is an important resource of information on crustal structure. The aim of this work is giving a reliable geometry of the major faults relative to the kinematics of this region. The results obtained from various filtered maps (derivatives, upward continuation) of the gravity data, were used to generate a structural map of the studied area. Whilst the continuous wavelet transform method can help in automatic detection of elongated structures in 3-D, to estimate their strike direction, shape and depth. It gives a 3-D image or a model of the region and confirms the existence of several faults, localized or inferred, from former geological studies.

  2. Field test of a generic method for halogenated hydrocarbons: A vost test at a chemical manufacturing facility. Final report, September 1992-December 1993

    SciTech Connect

    McGaughey, J.F.; Bursey, J.T.; Merrill, R.G.

    1994-06-01

    In evaluating stationary source sampling and analytical methodology, two different source types are used. EPA is evaluating the volatile halogenated organic compounds listed in Title III of the Clean Air Act Amendments of 1990. An initial field evaluation study was conducted for the VOST (SW-846 sampling Method 0030, analytical Method 5041) at a coal fired steam generating plant. A chemical manufacturing facility was selected as a second test site. The presence of low levels of some of the compounds of interest was established by the VOST analysis of samples collected during a presurvey. The sampling plan followed the requirements of EPA Method 301, and the data were evaluated statistically. Of 23 volatile halogenated organic compounds tested, the VOST showed acceptable performance with respect to recovery and precision for 17.

  3. Heating hydrocarbon containing formations in a checkerboard pattern staged process

    SciTech Connect

    de Rouffignac, Eric Pierre; Pingo-Almada, Monica M; Miller, David Scott

    2009-06-02

    Method for treating a hydrocarbon containing formation are described herein. Methods may include providing heat to two or more first sections of the formation with one or more first heaters in two or more of the first sections. The provided heat may mobilize first hydrocarbons in two or more of the first sections. At least some of the mobilized first hydrocarbons are produced through production wells located in two or more second sections of the formation. The first sections and the second sections are arranged in a checkerboard pattern. A portion of at least one of the second sections proximate at least one production well is provided some heat from the mobilized first hydrocarbons, but is not conductively heated by heat from the first heaters. Heat may be provided to the second sections with one or more second heaters in the second sections to further heat the second sections.

  4. Crustal structure in the Falcón Basin area, northwestern Venezuela, from seismic and gravimetric evidence

    NASA Astrophysics Data System (ADS)

    Bezada, Maximiliano J.; Schmitz, Michael; Jácome, María Inés; Rodríguez, Josmat; Audemard, Franck; Izarra, Carlos; The Bolivar Active Seismic Working Group

    2008-05-01

    The Falcón Basin in northwestern Venezuela has a complex geological history driven by the interactions between the South American and Caribbean plates. Igneous intrusive bodies that outcrop along the axis of the basin have been associated with crustal thinning, and gravity modeling has shown evidence for a significantly thinned crust beneath the basin. In this study, crustal scale seismic refraction/wide-angle reflection data derived from onshore/offshore active seismic experiments are interpreted and forward-modeled to generate a P-wave velocity model for a ˜450 km long profile. The final model shows thinning of the crust beneath the Falcón Basin where depth to Moho decreases to 27 km from a value of 40 km about 100 km to the south. A deeper reflected phase on the offshore section is interpreted to be derived from the downgoing Caribbean slab. Velocity values were converted to density and the resulting gravimetric response was shown to be consistent with the regional gravity anomaly. The crustal thinning proposed here supports a rift origin for the Falcón Basin.

  5. Evaluation and mapping of PM2.5 atmospheric aerosols in Arasia region using PIXE and gravimetric measurements

    NASA Astrophysics Data System (ADS)

    Roumie, M.; Chiari, M.; Srour, A.; Sa'adeh, H.; Reslan, A.; Sultan, M.; Ahmad, M.; Calzolai, G.; Nava, S.; Zubaidi, Th.; Rihawy, M. S.; Hussein, T.; Arafah, D.-E.; Karydas, A. G.; Simon, A.; Nsouli, B.

    2016-03-01

    The present work is a part of a scientific study conducted among several Arab countries in west Asia, under an International Atomic Energy Agency (IAEA) regional technical cooperation project for Arasia region. The project aims at producing for the first time a database of particulate matter (PM) elemental concentrations in the region that will help in future air quality studies in order to identify commonalities and differences in the presence and contribution of fingerprint pollution sources among the Arasia Member States. The first regional campaign was launched simultaneously in Lebanon, Iraq, Jordan, Syria and United Arab Emirates, using a harmonized sampling and analysis protocol of PM10 and PM2.5 samples. Different samples, collected between October 2014 and February 2015, from the participating countries, were analyzed by PIXE technique and gravimetric measurements were also carried out. The first results of the study will be discussed in a regional perspective. Our study shows that concentrations of fine aerosol fractions are often exceeding the WHO standard values as well as showing some disparities in the obtained values between the different sampling sites. However, some trend similarities of variations with time could also be observed, suggesting a common influence by trans-boundary or external sources of air pollution.

  6. Quantification of in vitro wear of a synthetic meniscus implant using gravimetric and micro-CT measurements.

    PubMed

    Elsner, Jonathan J; Shemesh, Maoz; Shefy-Peleg, Adaya; Gabet, Yankel; Zylberberg, Eyal; Linder-Ganz, Eran

    2015-09-01

    A synthetic meniscus implant was recently developed for the treatment of patients with mild to moderate osteoarthritis with knee pain associated with medial joint overload. The implant is distinctively different from most orthopedic implants in its pliable construction, and non-anchored design, which enables implantation through a mini-arthrotomy without disruption to the bone, cartilage, and ligaments. Due to these features, it is important to show that the material and design can withstand knee joint conditions. This study evaluated the long-term performance of this device by simulating loading for a total of 5 million gait cycles (Mc), corresponding to approximately five years of service in-vivo. All five implants remained in good condition and did not dislodge from the joint space during the simulation. Mild abrasion was detected by electron microscopy, but µ-CT scans of the implants confirmed that the damage was confined to the superficial surfaces. The average gravimetric wear rate was 14.5 mg/Mc, whereas volumetric changes in reconstructed µ-CT scans point to an average wear rate of 15.76 mm(3)/Mc (18.8 mg/Mc). Particles isolated from the lubricant had average diameter of 15 µm. The wear performance of this polycarbonate-urethane meniscus implant concept under ISO-14243 loading conditions is encouraging. PMID:26057364

  7. Hydrological signal in polar motion excitation from a combination of geophysical and gravimetric series

    NASA Astrophysics Data System (ADS)

    Nastula, Jolanta; Winska, Malgorzata; Salstein, David A.

    2015-08-01

    One can estimate the hydrological signal in polar motion excitation as a residual, namely the difference between observed geodetic excitation functions (Geodetic Angular Momentum, GAM) and the sum of Atmospheric Angular Momentum (AAM) and Oceanic Angular Momentum (OAM).The aim of this study is to find the optimal model and results for hydrological excitation functions in terms of their agreement with the computed difference between GAM and atmospheric and oceanic signals.The atmospheric and oceanic model-based data that we use in this study are the geophysical excitation functions of AAM, OAM available from the Special Bureaus for the Atmosphere and Oceans of the Geophysical Global Fluids Center (GGFC) of the International Earth Rotation and Reference Systems Service (IERS). For the atmosphere and ocean, these functions are based on the mass and motion fields of the fluids.Global models of land hydrology are used to estimate hydrological excitation functions of polar motion (Hydrological Angular Momentum - HAM). These HAM series are the mass of water substance determined from the various types of land-based hydrological reservoirs. In addition the HAM are estimated from spherical harmonic coefficients of the Earth’s gravity field. We use several sets of degree-2, order-1 harmonics of the Earth’s gravity field, derived from the Gravity Recovery and Climate Experiment (GRACE), Satellite Laser Ranging (SLR), and Global Navigation Satellite Systems (GNSS) data.Finally, these several different HAM series are used to determine the best model of hydrological excitation of polar motion. The model is found by looking for the combination of these series that fits the geodetic residuals using the least-square method.In addition, we will access model results from the Coupled Model Intercomparison Project, fifth experiment (CMIP-5) to examine atmospheric excitations from the twentieth century and estimates for the twenty-first century to see the possible signals and trends

  8. Hydrocarbon-enhanced particulate filter regeneration via microwave ignition

    DOEpatents

    Gonze, Eugene V.; Brown, David B.

    2010-02-02

    A regeneration method for a particulate filter includes estimating a quantity of particulate matter trapped within the particulate filter, comparing the quantity of particulate matter to a predetermined quantity, heating at least a portion of the particulate filter to a combustion temperature of the particulate matter, and introducing hydrocarbon fuel to the particulate filter. The hydrocarbon fuel facilitates combustion of the particulate matter to regenerate the particulate filter.

  9. Development of a gas chromatography/mass spectrometry method to quantify several urinary monohydroxy metabolites of polycyclic aromatic hydrocarbons in occupationally exposed subjects.

    PubMed

    Campo, Laura; Rossella, Federica; Fustinoni, Silvia

    2008-11-15

    The aim of this study was the development of a method for the determination of 12 urinary monohydroxy metabolites of PAHs, namely 1-hydroxynaphthalene, 2-hydroxynaphthalene, 2-hydroxyfluorene, 9-hydroxyfluorene, 1-hydroxyphenanthrene, 2-hydroxyphenanthrene, 3-hydroxyphenanthrene, 4-hydroxyphenanthrene, 9-hydroxyphenanthrene, 1-hydroxypyrene, 6-hydroxychrysene, and 3-hydroxybenzo[a]pyrene. Analytes were determined in the presence of deuterated analogues as internal standards, by GC/MS operating in the electron impact mode. Sample preparation was performed by enzymatic hydrolysis of glucoronate and sulphate conjugates of hydroxy metabolites of PAHs, liquid-liquid extraction with n-hexane, and derivatization with a silylating reagent. The method is very specific, limits of quantification are in the range 0.1-1.4 microg/l, and range of linearity is from limit of detection to 208 microg/l. Within- and between-run precision, expressed as coefficient of variation, are <20%; accuracy for most analytes is within 20% of the theoretical value. An application of the proposed method to the analysis of 10 urine samples from coke-oven workers shows that 1-hydroxynaphthalene and 2-hydroxyfluorene were the most abundant compounds (median 61.4 and 69.7 microg/l, respectively), while 6-hydroxychrysene, and 3-hydroxybenzo[a]pyrene were always below the quantification limit. PMID:18952507

  10. Hydrocarbons in Washington coastal sediments

    NASA Astrophysics Data System (ADS)

    Prahl, Fredrick G.; Carpenter, Roy

    1984-06-01

    The sources and distributions of polycyclic aromatic hydrocarbons (PAH) and aliphatic hydrocarbons are characterized in seventeen sediments from a highly river-influenced sedimentary environment off the southwestern coast of Washington. The major hydrocarbons are land-derived, introduced as preformed compounds and display long-term stability in sediment cores. A series of PAH of anthropogenic origin and two naturally derived compounds, retene and perylene, dominate the PAH composition in these sediments. Plantwax n-alkanes are the major aliphatic hydrocarbon constituents. Aliphatic hydrocarbons of marine origin, pristane and a series of four acyclic, multibranched C 25 polyolefins, are also observed in many sediments. The concentrations of these marine-derived hydrocarbons decrease to negligible levels rapidly with sediment depth from the sea-sediment interface, suggesting degradation. In general, the major land-derived hydrocarbons are concentrated in the midshelf silt deposit which extends northwestward along the continental shelf from the Columbia River mouth. A quantitatively more minor, natural series of phenanthrene homologs, also of terrestrial origin, is preferentially advected further offshore and deposited in continental slope sediments. These distributions are consistent with recognized particle associations for these compounds and sediment dispersal processes in this coastal environment. Sediment core records suggest the present pattern of dispersal has persisted for at least the past century and possibly since the Late Pleistocene.

  11. Catalytic conversion of alcohols having at least three carbon atoms to hydrocarbon blendstock

    DOEpatents

    Narula, Chaitanya K.; Davison, Brian H.

    2015-11-13

    A method for producing a hydrocarbon blendstock, the method comprising contacting at least one saturated acyclic alcohol having at least three and up to ten carbon atoms with a metal-loaded zeolite catalyst at a temperature of at least 100°C and up to 550°C, wherein the metal is a positively-charged metal ion, and the metal-loaded zeolite catalyst is catalytically active for converting the alcohol to the hydrocarbon blendstock, wherein the method directly produces a hydrocarbon blendstock having less than 1 vol % ethylene and at least 35 vol % of hydrocarbon compounds containing at least eight carbon atoms.

  12. A new receptor model-incremental lifetime cancer risk method to quantify the carcinogenic risks associated with sources of particle-bound polycyclic aromatic hydrocarbons from Chengdu in China.

    PubMed

    Liu, Gui-Rong; Peng, Xing; Wang, Rong-Kang; Tian, Ying-Ze; Shi, Guo-Liang; Wu, Jian-Hui; Zhang, Pu; Zhou, Lai-Dong; Feng, Yin-Chang

    2015-01-01

    PM10 and PM2.5 samples were simultaneously collected during a one-year monitoring period in Chengdu. The concentrations of 16 particle-bound polycyclic aromatic hydrocarbons (Σ16PAHs) were measured. Σ16PAHs concentrations varied from 16.85 to 160.24 ng m(-3) and 14.93 to 111.04ngm(-3) for PM10 and PM2.5, respectively. Three receptor models (principal component analysis (PCA), positive matrix factorization (PMF), and Multilinear Engine 2 (ME2)) were applied to investigate the sources and contributions of PAHs. The results obtained from the three receptor models were compared. Diesel emissions, gasoline emissions, and coal and wood combustion were the primary sources. Source apportionment results indicated that these models were able to track the ΣPAHs. For the first time, the cancer risks for each identified source were quantitatively calculated for ingestion and dermal contact routes by combining the incremental lifetime cancer risk (ILCR) values with the estimated source contributions. The results showed that gasoline emissions posed the highest cancer risk, even though it contributed less to Σ16PAHs. The results and method from this work can provide useful information for quantifying the toxicity of source categories and studying human health in the future. PMID:25464284

  13. Microextraction by packed sorbent coupled with gas chromatography-mass spectrometry: a comparison between "draw-eject" and "extract-discard" methods under equilibrium conditions for the determination of polycyclic aromatic hydrocarbons in water.

    PubMed

    Quinto, Maurizio; Spadaccino, Giuseppina; Nardiello, Donatella; Palermo, Carmen; Amodio, Pierluigi; Li, Donghao; Centonze, Diego

    2014-12-01

    In this work, two different extraction procedures for the analysis of different polycyclic aromatic hydrocarbons (PAHs) in water by microextraction by packed sorbent (MEPS) have been compared in terms of sensitivity, reliability and time of analysis. The first method, called "draw-eject", consists of a sequence of cycles of aspirations and injections in the same vial; the second one, called "extract-discard", consists of a similar cycle sequence, but the aspired sample in this case is discarded into waste. The relevant partition equilibriums and extraction rates have been calculated by multivariate regression from the data obtained after MEPS gas chromatography-mass spectrometry (MEPS-GC-MS) analysis of 16 PAHs from water samples. Partitioning parameters for a priori prediction of solute sorption equilibrium, recoveries and preconcentration effects in aqueous and solvent systems have been calculated and compared for the two extraction procedures. Finally, real samples from sea, agricultural irrigation wells, streams and tap water were analyzed. Detection (S/N≥3) and quantification (S/N≥10) limits were calculated for the extraction processes. Under the experimental conditions used for the "draw-eject" procedure, these values were in the range 0.5-2 ng L(-1) and 1.6-6.2 ng L(-1), while for the "extract-discard" procedure they ranged from 0.2 to 0.8 ng L(-1) and from 0.8 to 2.0 ng L(-1), respectively. PMID:25456584

  14. Validation of one-step cleanup and separation method of polychlorinated biphenyls, organochlorine pesticides, and polycyclic aromatic hydrocarbons from atmospheric gas- and particle-phase samples.

    PubMed

    Yenisoy-Karakaş, Serpil; Gaga, Eftade O

    2013-10-15

    A one-step cleanup method is described for the determination of PAHs, PCBs and OCPs in air (gas and particulate phase) samples. Analytes were extracted from ambient air samples using soxhlet extraction with a solvent mixture of dichloromethane and petroleum ether (1:4) for 24h. They were concentrated, separated and fractionated on a florisil and alumina column. The amounts of florisil (1g or 2g) with/without alumina were tested in the cleanup column. The study systematically investigated the effects of solvent types, and the amounts of florisil and alumina, on the performance of the cleanup process. The first fraction was eluted with 25 mL hexane, and analyzed for PCBs. The second fraction was collected via 40 mL hexane-ethyl acetate (1:1) solvent mixture, and analyzed for OCPs and PAHs. The optimized method yielded average recoveries between 88% and 99% for PCBs; 56% and 118% for PAHs; and 51% and 128% for OCPs. Other validation parameters were also investigated, such as MDL, LOQ, linear range, sensitivity (r(2)). An oven-program optimization and adjustment of GC-MS were performed. For internal quality control, surrogate recoveries and field blanks values were calculated. External calibration curves were prepared for PAHs, and internal calibration curves were preferred for OCP and PCBs. PMID:24054572

  15. Catalytic pyrolysis of wheat bran for hydrocarbons production in the presence of zeolites and noble-metals by using TGA-FTIR method.

    PubMed

    Lazdovica, K; Liepina, L; Kampars, V

    2016-05-01

    Pyrolysis of wheat bran with or without catalysts was investigated using TGA-FTIR method in order to determine the influence of zeolite and noble metal catalysts on the evolution profile and relative yield of the volatile compounds. The addition of all catalysts decreased the volatile matter of wheat bran from 76.3% to 75.9%, 73.9%, 73.5%, 69.7% and increased the solid residue from 18.0% to 18.4%, 20.4%, 20.8%, 24.6% under the catalyst of ZSM-5, 5% Pd/C, MCM-41, and 5% Pt/C. Noble-metal catalysts had higher activity for deoxygenation of compounds containing carbonyl, carboxyl, and hydroxyl groups than zeolites. Degradation of nitrogen containing compounds atom proceeded better in presence of zeolites. Noble-metal catalysts promoted formation of aromatics and changed the profiles of evolved compounds whereas zeolites advanced formation of aliphatics and olefins. PMID:26874441

  16. BIOTIGER, A NATURAL MICROBIAL PRODUCT FOR ENHANCED HYDROCARBON RECOVERY FROM OIL SANDS.

    SciTech Connect

    Brigmon, R; Topher Berry, T; Whitney Jones, W; Charles Milliken, C

    2008-05-27

    BioTiger{trademark} is a unique microbial consortia that resulted from over 8 years of extensive microbiology screening and characterization of samples collected from a century-old Polish waste lagoon. BioTiger{trademark} shows rapid and complete degradation of aliphatic and aromatic hydrocarbons, produces novel surfactants, is tolerant of both chemical and metal toxicity and shows good activity at temperature and pH extremes. Although originally developed and used by the U.S. Department of Energy for bioremediation of oil-contaminated soils, recent efforts have proven that BioTiger{trademark} can also be used to increase hydrocarbon recovery from oil sands. This enhanced ex situ oil recovery process utilizes BioTiger{trademark} to optimize bitumen separation. A floatation test protocol with oil sands from Ft. McMurray, Canada was used for the BioTiger{trademark} evaluation. A comparison of hot water extraction/floatation test of the oil sands performed with BioTiger{trademark} demonstrated a 50% improvement in separation as measured by gravimetric analysis in 4 h and a five-fold increase at 25 hr. Since BioTiger{trademark} performs well at high temperatures and process engineering can enhance and sustain metabolic activity, it can be applied to enhance recovery of hydrocarbons from oil sands or other complex recalcitrant matrices.

  17. Effect of hydrocarbon fuel type on fuel

    NASA Technical Reports Server (NTRS)

    Wong, E. L.; Bittker, D. A.

    1982-01-01

    A modified jet fuel thermal oxidation tester (JFTOT) procedure was used to evaluate deposit and sediment formation for four pure hydrocarbon fuels over the temperature range 150 to 450 C in 316-stainless-steel heater tubes. Fuel types were a normal alkane, an alkene, a naphthene, and an aromatic. Each fuel exhibited certain distinctive deposit and sediment formation characteristics. The effect of aluminum and 316-stainless-steel heater tube surfaces on deposit formation for the fuel n-decane over the same temperature range was investigated. Results showed that an aluminum surface had lower deposit formation rates at all temperatures investigated. By using a modified JFTOT procedure the thermal stability of four pure hydrocarbon fuels and two practical fuels (Jet A and home heating oil no. 2) was rated on the basis of their breakpoint temperatures. Results indicate that this method could be used to rate thermal stability for a series of fuels.

  18. Application of paleomagnetic techniques for dating hydrocarbon migration events

    SciTech Connect

    Elmore, R.D.

    1988-01-01

    Establishing a relationship between hydrocarbon migration and the precipitation of authigenic magnetite is important for the development of a method to date hydrocarbon migration using paleomagnetic techniques. Important evidence for the relationship comes from a study of light and dark-banded calcite speleothems that occur in Ordovician limestones in southern Oklahoma. The speleothems are Permian in age, based on interbedded fossils. The dark bands contain primary fluid inclusions filled with hydrocarbons that are not extensively biograded. They also possess over an order of magnitude stronger magnetization than light bands. Paleomagnetic and rock magnetic data indicate that the magnetization in the dark bands was acquired during the Early Permian and resides in magnetite. Spheres, interpreted to be authigenic magnetite, are also found in magnetic extracts from the dark calcite. The results from the light and dark bands suggest that chemical conditions created by the hydrocarbons caused precipitation of authigenic magnetite and acquisition of the associated chemical remanent magnetization.

  19. Organic geochemistry of the Vindhyan sediments: Implications for hydrocarbons

    NASA Astrophysics Data System (ADS)

    Dayal, A. M.; Mani, Devleena; Madhavi, T.; Kavitha, S.; Kalpana, M. S.; Patil, D. J.; Sharma, Mukund

    2014-09-01

    The organic geochemical methods of hydrocarbon prospecting involve the characterization of sedimentary organic matter in terms of its abundance, source and thermal maturity, which are essential prerequisites for a hydrocarbon source rock. In the present study, evaluation of organic matter in the outcrop shale samples from the Semri and Kaimur Groups of Vindhyan basin was carried out using Rock Eval pyrolysis. Also, the adsorbed low molecular weight hydrocarbons, methane, ethane, propane and butane, were investigated in the near surface soils to infer the generation of hydrocarbons in the Vindhyan basin. The Total Organic Carbon (TOC) content in shales ranges between 0.04% and 1.43%. The S1 (thermally liberated free hydrocarbons) values range between 0.01-0.09 mgHC/gRock (milligram hydrocarbon per gram of rock sample), whereas the S2 (hydrocarbons from cracking of kerogen) show the values between 0.01 and 0.14 mgHC/gRock. Based on the Tmax (temperature at highest yield of S2) and the hydrogen index (HI) correlations, the organic matter is characterized by Type III kerogen. The adsorbed soil gas, CH4 (C1), C2H6 (C2), C3H8 (C3) and nC4H10, (nC4), concentrations measured in the soil samples from the eastern part of Vindhyan basin (Son Valley) vary from 0 to 186 ppb, 0 to 4 ppb, 0 to 5 ppb, and 0 to 1 ppb, respectively. The stable carbon isotope values for the desorbed methane (δ13C1) and ethane (δ13C2) range between -45.7‰ to -25.2‰ and -35.3‰ to -20.19‰ (VPDB), respectively suggesting a thermogenic source for these hydrocarbons. High concentrations of thermogenic hydrocarbons are characteristic of areas around Sagar, Narsinghpur, Katni and Satna in the Son Valley. The light hydrocarbon concentrations (C1-C4) in near surface soils of the western Vindhyan basin around Chambal Valley have been reported to vary between 1-2547 ppb, 1-558 ppb, 1-181 ppb, 1-37 ppb and 1-32 ppb, respectively with high concentrations around Baran-Jhalawar-Bhanpur-Garot regions (Kumar

  20. On the spectral combination of satellite gravity model, terrestrial and airborne gravity data for local gravimetric geoid computation

    NASA Astrophysics Data System (ADS)

    Jiang, Tao; Wang, Yan Ming

    2016-07-01

    One of the challenges for geoid determination is the combination of heterogeneous gravity data. Because of the distinctive spectral content of different data sets, spectral combination is a suitable candidate for its solution. The key to have a successful combination is to determine the proper spectral weights, or the error degree variances of each data set. In this paper, the error degree variances of terrestrial and airborne gravity data at low degrees are estimated by the aid of a satellite gravity model using harmonic analysis. For higher degrees, the error covariances are estimated from local gravity data first, and then used to compute the error degree variances. The white and colored noise models are also used to estimate the error degree variances of local gravity data for comparisons. Based on the error degree variances, the spectral weights of satellite gravity models, terrestrial and airborne gravity data are determined and applied for geoid computation in Texas area. The computed gravimetric geoid models are tested against an independent, highly accurate geoid profile of the Geoid Slope Validation Survey 2011 (GSVS11). The geoid computed by combining satellite gravity model GOCO03S and terrestrial (land and DTU13 altimetric) gravity data agrees with GSVS11 to ±1.1 cm in terms of standard deviation along a line of 325 km. After incorporating the airborne gravity data collected at 11 km altitude, the standard deviation is reduced to ±0.8 cm. Numerical tests demonstrate the feasibility of spectral combination in geoid computation and the contribution of airborne gravity in an area of high quality terrestrial gravity data. Using the GSVS11 data and the spectral combination, the degree of correctness of the error spectra and the quality of satellite gravity models can also be revealed.

  1. Low-Temperature Catalytic Process To Produce Hydrocarbons From Sugars

    DOEpatents

    Cortright, Randy D.; Dumesic, James A.

    2005-11-15

    Disclosed is a method of producing hydrogen from oxygenated hydrocarbon reactants, such as methanol, glycerol, sugars (e.g. glucose and xylose), or sugar alcohols (e.g. sorbitol). The method takes place in the condensed liquid phase. The method includes the steps of reacting water and a water-soluble oxygenated hydrocarbon in the presence of a metal-containing catalyst. The catalyst contains a metal selected from the group consisting of Group VIIIB transitional metals, alloys thereof, and mixtures thereof. The disclosed method can be run at lower temperatures than those used in the conventional steam reforming of alkanes.

  2. Development of a solid-phase microextraction-based method for sampling of persistent chlorinated hydrocarbons in an urbanized coastal environment.

    PubMed

    Zeng, Eddy Y; Tsukada, David; Diehl, Dario W

    2004-11-01

    Solid-phase microextraction (SPME) has been used as an in situ sampling technique for a wide range of volatile organic chemicals, but SPME field sampling of nonvolatile organic pollutants has not been reported. This paper describes the development of an SPME-based sampling method employing a poly(dimethylsiloxane) (PDMS)-coated (100-microm thickness) fiber as the sorbent phase. The laboratory-calibrated PDMS-coated fibers were used to construct SPME samplers, and field tests were conducted at three coastal locations off southern California to determine the equilibrium sampling time and compare the efficacy of the SPME samplers with that of an Infiltrex 100 water pumping system (Axys Environmental Systems Ltd., Sidney, British Columbia, Canada). p,p'-DDE and o,p'-DDE were the components consistently detected in the SPME samples among 42 polychlorinated biphenyl congeners and 17 chlorinated pesticidestargeted. SPME samplers deployed attwo locations with moderate and high levels of contamination for 18 and 30 d, respectively, attained statistically identical concentrations of p,p'-DDE and o,p'-DDE. In addition, SPME samplers deployed for 23 and 43 d, respectively, at a location of low contamination also contained statistically identical concentrations of p,p'-DDE. These results indicate that equilibrium could be reached within 18 to 23 d. The concentrations of p,p'-DDE, o,p'-DDE, or p,p'-DDD obtained with the SPME samplers and the Infiltrex 100 system were virtually identical. In particular, two water column concentration profiles of p,p'-DDE and o,p'-DDE acquired by the SPME samplers at a highly contaminated site on the Palos Verdes Shelf overlapped with the profiles obtained by the Infiltrex 100 system in 1997. The field tests not only reveal the advantages of the SPME samplers compared to the Infiltrex 100 system and other integrative passive devices but also indicate the need to improve the sensitivity of the SPME-based sampling technique. PMID:15575294

  3. Methods for polynuclear aromatic hydrocarbon determination in air samples using polar-bonded phase HPLC and GC-MS with application to oil refinery samples

    SciTech Connect

    Karlesky, K.L.

    1985-01-01

    Particle samples were collected using high volume air samplers fitted with glass fiber filters or with a cascade impactor containing paper filters. They were then cleaned using either extraction with dimethylsulfoxide and pentane or utilizing a small cartridge containing a diamine polar-bonded phase material, the second method being more effective. Vapor phase PAH were sampled using an apparatus designed in the laboratory. After collection, the resins were desorbed with solvent and the PAH content was determined. The suitability of the resins decrease in the following order: Amberlite XAD-2, Chromosorb 105, Tenax GC, coconut charcoal, and Ambesorb XE-348. High performance liquid chromatography (HPLC) was used to determine the behavior of PAH in the normal and reversed phase on polar-bonded phases containing amine, diamine, and pyrrolidone substrates. Results support the proposed mechanism in the normal phase and indicate that both a partitioning and liquid-solid adsorption mechanism takes place in the reversed phase depending upon the mobile phase. Occasionally, these polar-bonded phases can be deactivated by the formation of amine-carbonyl complexes from polar aldehydes or ketones in the solvent or sample. Deactivation can be reversed by flushing with water to hydrolyze the Schiff's base imine back to the amine. Gas chromatography-mass spectroscopy (GC-MS) was used to analyze air samples from oil refineries in Port Arthur, collected over a period of three years. The analytical procedures are applied to the collected samples to determine if they contain detectable amounts of PAH. The GC-MS analysis was adequate for this study but the use of SIM detection is preferred because of the greater sensitivity for PAH.

  4. Uncertainties in hydrocarbon charge prediction

    NASA Astrophysics Data System (ADS)

    Visser, W.; Bell, A.

    Computer simulations allow the prediction of hydrocarbon volumes, composition and charge timing in undrilled petroleum prospects. Whereas different models may give different hydrocarbon charge predictions, it has now become evident that a dominant cause of erroneous predictions is the poor quality of input data. The main culprit for prediction errors is the uncertainty in the initial hydrogen index (H/C) of the source rock. A 10% uncertainty in the H/C may lead to 50% error in the predicted hydrocarbon volumes, and associated gas-oil ratio. Similarly, uncertainties in the maximum burial temperature and the kinetics of hydrocarbon generation may lead to 20-50% error. Despite this, charge modelling can have great value for the ranking of prospects in the same area with comparable geological histories.

  5. Spontaneous ultra-weak light emissions from wheat seedlings are rhythmic and synchronized with the time profile of the local gravimetric tide

    NASA Astrophysics Data System (ADS)

    Moraes, Thiago A.; Barlow, Peter W.; Klingelé, Emile; Gallep, Cristiano M.

    2012-06-01

    Semi-circadian rhythms of spontaneous photon emission from wheat seedlings germinated and grown in a constant environment (darkened chamber) were found to be synchronized with the rhythm of the local gravimetric (lunisolar) tidal acceleration. Time courses of the photon-count curves were also found to match the growth velocity profile of the seedlings. Pair-wise analyses of the data—growth, photon count, and tidal—by local tracking correlation always revealed significant coefficients ( P > 0.7) for more than 80% of any of the time periods considered. Using fast Fourier transform, the photon-count data revealed periodic components similar to those of the gravimetric tide. Time courses of biophoton emissions would appear to be an additional, useful, and innovative tool in both chronobiological and biophysical studies.

  6. Hydrocarbon potential of Morocco

    SciTech Connect

    Achnin, H.; Nairn, A.E.M.

    1988-08-01

    Morocco lies at the junction of the African and Eurasian plates and carries a record of their movements since the end of the Precambrian. Four structural regions with basins and troughs can be identified: Saharan (Tarfaya-Ayoun and Tindouf basins); Anti-Atlas (Souss and Ouarzazate troughs and Boudnib basin); the Essaouria, Doukkala, Tadla, Missour, High Plateau, and Guercif basins; and Meseta and Rif (Rharb and Pre-Rif basins). The targets in the Tindouf basin are Paleozoic, Cambrian, Ordovician (clastics), Devonian (limestones), and Carboniferous reservoirs sourced primarily by Silurian shales. In the remaining basins, excluding the Rharb, the reservoirs are Triassic detritals, limestones at the base of the Lias and Dogger, Malm detritals, and sandy horizons in the Cretaceous. In addition to the Silurian, potential source rocks include the Carboniferous and Permo-Carboniferous shales and clays; Jurassic shales, marls, and carbonates; and Cretaceous clays. In the Rharb basin, the objectives are sand lenses within the Miocene marls. The maturation level of the organic matter generally corresponds to oil and gas. The traps are stratigraphic (lenses and reefs) and structural (horsts and folds). The seals in the pre-Jurassic rocks are shales and evaporites; in the younger rocks, shales and marl. Hydrocarbon accumulations have been found in Paleozoic, Triassic, Liassic, Malm, and Miocene rocks.

  7. Evaluation of hydrocarbon potential

    SciTech Connect

    Cashman, P.H.; Trexler, J.H. Jr.

    1992-09-30

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

  8. Illite and hydrocarbon exploration

    PubMed Central

    Pevear, David R.

    1999-01-01

    Illite is a general term for the dioctahedral mica-like clay mineral common in sedimentary rocks, especially shales. Illite is of interest to the petroleum industry because it can provide a K-Ar isotope date that constrains the timing of basin heating events. It is critical to establish that hydrocarbon formation and migration occurred after the formation of the trap (anticline, etc.) that is to hold the oil. Illite also may precipitate in the pores of sandstone reservoirs, impeding fluid flow. Illite in shales is a mixture of detrital mica and its weathering products with diagenetic illite formed by reaction with pore fluids during burial. K-Ar ages are apparent ages of mixtures of detrital and diagenetic end members, and what we need are the ages of the end members themselves. This paper describes a methodology, based on mineralogy and crystallography, for interpreting the K-Ar ages from illites in sedimentary rocks and for estimating the ages of the end members. PMID:10097055

  9. Aliphatic hydrocarbons of the fungi.

    NASA Technical Reports Server (NTRS)

    Weete, J. D.

    1972-01-01

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

  10. Bioassay of polycyclic aromatic hydrocarbons

    SciTech Connect

    Van Kirk, E.A.

    1980-08-01

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

  11. Extraction of petroleum hydrocarbons from soil by mechanical shaking

    SciTech Connect

    Schwab, A.P.; Su, J.; Wetzel, S.; Pekarek, S.; Banks, M.K.

    1999-06-01

    A shaking extraction method for petroleum hydrocarbons in soil was developed and compared to Soxhlet extraction. Soxhlet extraction is an EPA-approved method for volatile and semivolatile organic contaminants from solid materials, but it has many disadvantages including long extraction periods and potential loss of volatile compounds. When field-moist soils are used, variability in subsamples is higher, and the extraction of hydrocarbons with a nonpolar solvent may be less efficient. A shaking method was designed to fill the need for simpler and more efficient extraction of petroleum hydrocarbons from soil. A systematic study of extraction conditions was performed for various soil types, soil weights, solvents, extraction times, and extraction cycles. The results were compared to those for Soxhlet extraction. Shaking 1 g of soil with a sequence of three 10-mL aliquots of dichloromethane or acetone was found to be equivalent to Soxhlet extraction for total petroleum hydrocarbons and polycyclic aromatic hydrocarbons. Shaking with acetone was more consistent than all other methods for the extraction of specific compounds from aged, contaminated soil. The shaking method appears to be applicable to a wide range of soil types and petroleum contaminants but should be compared to Soxhlet extraction for new conditions.

  12. Surface ionization of terpene hydrocarbons

    SciTech Connect

    Zandberg, E.Y.; Nezdyurov, A.L.; Paleev, V.I.; Ponomarev, D.A.

    1986-09-01

    By means of a surface ionization indicator for traces of materials in the atmosphere it has been established that many natural materials containing terpenes and their derivatives are ionized on the surface of heated molybdenum oxide at atmospheric air pressure. A mass-spectrometer method has been used to explain the mechanism of ionization of individual terpene hydrocarbons and to establish its principles. The ionization of ..cap alpha..-pinene, alloocimene, camphene, and also adamantane on oxidized tungsten under vacuum conditions has been investigated. The ..cap alpha..-pinene and alloocimene are ionized by surface ionization but camphene and adamantane are not ionized under vacuum conditions. The surface ionization mass spectra of ..cap alpha..-pinene and alloocimene are of low line brightness in comparison with electron ionization mass spectra and differ between themselves. The temperature relations for currents of the same compositions of ions during ionization of ..cap alpha..-pinene and alloocimene are also different, which leads to the possibility of surface ionization analysis of mixtures of terpenes being ionized. The ionization coefficients of alloocimene and ..cap alpha..-pinene on oxidized tungsten under temperatures optimum for ionization and the ionization potentials of alloocimene molecules and of radicals (M-H) of both compounds have been evaluated.

  13. Deuterated polycyclic aromatic hydrocarbons: Revisited

    NASA Astrophysics Data System (ADS)

    Doney, K. D.; Candian, A.; Mori, T.; Onaka, T.; Tielens, A. G. G. M.

    2016-02-01

    Aims: The amount of deuterium locked up in polycyclic aromatic hydrocarbons (PAHs) has to date been an uncertain value. We present a near-infrared (NIR) spectroscopic survey of Hii regions in the Milky Way, Large Magellanic Cloud, and Small Magellanic Cloud obtained with AKARI, which aims to search for features indicative of deuterated PAHs (PAD or Dn-PAH) to better constrain the D/H ratio of PAHs. Methods: Fifty-three Hii regions were observed in the NIR (2.5-5 μm), using the Infrared Camera (IRC) on board the AKARI satellite. Through comparison of the observed spectra with a theoretical model of deuterated PAH vibrational modes, the aromatic and (a)symmetric aliphatic C-D stretch modes were identified. Results: We see emission features between 4.4-4.8 μm, which could be unambiguously attributed to deuterated PAHs in only six of the observed sources, all of which are located in the Milky Way. In all cases, the aromatic C-D stretching feature is weaker than the aliphatic C-D stretching feature, and, in the case of M17b, this feature is not observed at all. Based on the weak or absent PAD features in most of the observed spectra, it is suggested that the mechanism for PAH deuteration in the ISM is uncommon.

  14. Comparison of measurements with PetroSense{reg_sign} Portable Hydrocarbon Analyzer (PHA 100) and laboratory analysis of bailed samples (EPA method 8015M) when used in monitoring sparging process

    SciTech Connect

    Saini, D.P.; Wing, T.; Dandge, D.K.; Leclerc, R.; Sword, M.A.; Havens, S.; Worland, J.R.

    1995-12-31

    The PetroSense{reg_sign} PHA-100 is a portable hydrocarbon analyzer that can measure total hydrocarbons in real time, in-situ, in water, vapor and the water vapor interface. The performance of the PetroSense{reg_sign} PHA-100 in the field when used to monitor the levels of hydrocarbons in a monitoring well at an Under Ground Storage (UST) site in Las Vegas is discussed, and compared to the lab analysis of the water samples taken at the same time. The authors also discuss its use for monitoring the progress of a sparging process at another site in Las Vegas. In both cases the PHA-100 showed excellent correlation with lab analyzed samples.

  15. Polycyclic Aromatic Hydrocarbons

    NASA Technical Reports Server (NTRS)

    Salama, Farid

    2010-01-01

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

  16. Loading effect of a self-consistent equilibrium ocean pole tide on the gravimetric parameters of the gravity pole tides at superconducting gravimeter stations

    NASA Astrophysics Data System (ADS)

    Chen, Xiaodong; Ducarme, Bernard; Sun, Heping; Xu, Jianqiao

    2008-05-01

    The gravimetric parameters of the gravity pole tide are the amplitude factor δ, which is the ratio of gravity variations induced by polar motion for a real Earth to variations computed for a rigid one, and the phase difference κ between the observed and the rigid gravity pole tide. They can be estimated from the records of superconducting gravimeters (SGs). However, they are affected by the loading effect of the ocean pole tide. Recent results from TOPEX/Poseidon (TP) altimeter confirm that the ocean pole tide has a self-consistent equilibrium response. Accordingly, we calculate the gravity loading effects as well as their influence on the gravimetric parameters of gravity pole tide at all the 26 SG stations in the world on the assumption of a self-consistent equilibrium ocean pole tide model. The gravity loading effect is evaluated between 1 January 1997 and 31 December 2006. Numerical results show that the amplitude of the gravity loading effect reaches 10 -9 m s -2, which is larger than the accuracy (10 -10 m s -2) of a SG. The gravimetric factor δ is 1% larger at all SG stations. Then, the contribution of a self-consistent ocean pole tide to the pole tide gravimetric parameters cannot be ignored as it exceeds the current accuracy of the estimation of the pole tide gravity factors. For the nine stations studied in Ducarme et al. [Ducarme, B., Venedikov, A.P., Arnoso, J., et al., 2006. Global analysis of the GGP superconducting gravimeters network for the estimation of the pole tide gravimetric amplitude factor. J. Geodyn. 41, 334-344.], the mean of the modeled tidal factors δm = 1.1813 agrees very well with the result of a global analysis δCH = 1.1816 ± 0.0047 in that paper. On the other hand, the modeled phase difference κm varies from -0.273° to 0.351°. Comparing to the two main periods of the gravity pole tide, annual period and Chandler period, κm is too small to be considered. Therefore, The computed time difference κL induced by a self

  17. Chemistry in the Center for Catalytic Hydrocarbon Functionalization. An Energy Frontier Research Center

    SciTech Connect

    Golisz, Suzanne R.; Gunnoe, T. Brent; Goddard, William A.; Groves, John T.; Periana, Roy A.

    2010-12-02

    Selective catalysts that activate small molecules such as hydrocarbons, dioxygen, water, carbon dioxide and dihydrogen are central to new technologies for the use of alternative energy sources. For example, controlled hydrocarbon functionalization can lead to high impact technologies, but such catalysts require a level of molecular control beyond current means. The Center for Catalytic Hydrocarbon Functionalization facilitates collaborations among research groups in catalysis, materials, electrochemistry, bioinorganic chemistry and quantum mechanics to develop, validate and optimize new methods to rearrange the bonds of hydrocarbons, activate and transform water and carbon dioxide, implement enzymatic strategies into synthetic systems and design optimal environments for catalysis.

  18. Geophysical Signitures From Hydrocarbon Contaminated Aquifers

    NASA Astrophysics Data System (ADS)

    Abbas, M.; Jardani, A.

    2015-12-01

    The task of delineating the contamination plumes as well as studying their impact on the soil and groundwater biogeochemical properties is needed to support the remediation efforts and plans. Geophysical methods including electrical resistivity tomography (ERT), induced polarization (IP), ground penetrating radar (GPR), and self-potential (SP) have been previously used to characterize contaminant plumes and investigate their impact on soil and groundwater properties (Atekwana et al., 2002, 2004; Benson et al., 1997; Campbell et al., 1996; Cassidy et al., 2001; Revil et al., 2003; Werkema et al., 2000). Our objective was to: estimate the hydrocarbon contamination extent in a contaminated site in northern France, and to adverse the effects of the oil spill on the groundwater properties. We aim to find a good combination of non-intrusive and low cost methods which we can use to follow the bio-remediation process, which is planned to proceed next year. We used four geophysical methods including electrical resistivity tomography, IP, GPR, and SP. The geophysical data was compared to geochemical ones obtained from 30 boreholes installed in the site during the geophysical surveys. Our results have shown: low electrical resistivity values; high chargeability values; negative SP anomalies; and attenuated GPR reflections coincident with groundwater contamination. Laboratory and field geochemical measurements have demonstrated increased groundwater electrical conductivity and increased microbial activity associated with hydrocarbon contamination of groundwater. Our study results support the conductive model suggested by studies such as Sauck (2000) and Atekwana et al., (2004), who suggest that biological alterations of hydrocarbon contamination can substantially modify the chemical and physical properties of the subsurface, producing a dramatic shift in the geo-electrical signature from resistive to conductive. The next stage of the research will include time lapse borehole

  19. Enrichment of light hydrocarbon mixture

    SciTech Connect

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

    2010-08-10

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

  20. Enrichment of light hydrocarbon mixture

    DOEpatents

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

    2011-11-29

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