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Sample records for matter kerogen concentrates

  1. Effect of Thermal Maturation on n-alkanes and Kerogen in Preserved Organic Matter: Implications for Paleoenvironment Biomarkers

    Science.gov (United States)

    Craven, O. D.; Longbottom, T. L.; Hockaday, W. C.; Blackaby, E.

    2017-12-01

    Understanding the effects of maturity on biomarkers is vital in assessing biomarker reliability in mature sediments. It is well known for n-alkanes that increased maturity shortens chain lengths and decreases the odd over even preference however, the amount of change in these variables has not been determined for different maturities and types of preserved organic matter. For this reason, it is difficult to judge the trustworthiness of even lightly matured samples for paleoenvironment reconstruction. Another complication is the difficulty of accurately determining maturity as many maturity indicators are error-prone or not appropriate at low maturities. Using hydrous pyrolysis, we artificially matured black shale samples with type I (lacustrine) and type II (marine) kerogen to measure changes in n-alkane length and odd over even preference. Whole rock samples underwent hydrous pyrolysis for 72 hours, at 250 °C, 300 °C, 325 °C, 350 °C, and 375 °C to cover a wide maturity range. From the immature and artificially matured samples, the bitumen was extracted and the saturate fraction was separated using column chromatography. The saturate fraction was analyzed for n-alkanes using gas chromatography-mass spectroscopy. Kerogen structural changes were also measured using solid-state 13C NMR to relate changes in n-alkane biomarkers to changes in kerogen structure. Results show that for type I bitumen the n-alkanes did not change at low maturities considered premature in terms of oil generation (<325 °C). The NMR spectra of the type I kerogen support the lack of change, at low maturities no changes in the aliphatic portion (Fal) were observed, however, after 325 °C Fal decreased with increasing maturity. The loss of Fal indicates kerogen contributing hydrocarbons to bitumen that cause changes in n-alkane measurements. The type II kerogen's Fal also decreased with increasing maturity, but unlike the type I kerogen Fal loss started at low maturities. The differences

  2. Effect of concentration of dispersed organic matter on optical maturity parameters. Interlaboratory results of the organic matter concentration working group of the ICCP

    Energy Technology Data Exchange (ETDEWEB)

    Mendonca Filho, J.G.; Kern, M.L.; Mendonca, J.O. [Palynofacies and Organic Facies Laboratory (LAFO), DEGL, IGEO, UFRJ, Cidade Universitaria, Rio de Janeiro (Brazil); Araujo, C.V.; Menezes, T.R.; Souza, I.V.A.F. [Petrobras R and D Center, Rio de Janeiro (Brazil); Borrego, A.G.; Suarez-Ruiz, I. [Instituto Nacional del Carbon, CSIC, Oviedo (Spain); Cook, A.; Ranasinghe, P. [Keiraville Konsultants Pty. Ltd, NSW (Australia); Flores, D. [University of Porto, Departamento de Geologia (Portugal); Hackley, P. [U.S. Geological Survey, MS 956 National Center Reston, VA (United States); Hower, J.C. [University of Kentucky, Center for Applied Energy Research, Lexington (United States); Kommeren, K. [Shell International Exploration and Production, Rijswijk (Netherlands); Kus, J. [Germany Federal Institute for Geosciences and Natural Resources in Geozentrum, Hannover (Germany); Mastalerz, M. [Indiana Geological Survey, Indiana University, Bloomington (United States); Newman, J. [Newman Energy Research Ltd, Christchurch (New Zealand); Ujiie, Y. [Graduate School of Science and Technology, Hirosaki University (Japan)

    2010-12-01

    The main objective of this work was to study the effect of the kerogen isolation procedures on maturity parameters of organic matter using optical microscopes. This work represents the results of the Organic Matter Concentration Working Group (OMCWG) of the International Committee for Coal and Organic Petrology (ICCP) during the years 2008 and 2009. Four samples have been analysed covering a range of maturity (low and moderate) and terrestrial and marine geological settings. The analyses comprise random vitrinite reflectance measured on both kerogen concentrate and whole rock mounts and fluorescence spectra taken on alginite. Eighteen participants from twelve laboratories from all over the world performed the analyses. Samples of continental settings contained enough vitrinite for participants to record around 50 measurements whereas fewer readings were taken on samples from marine setting. The scatter of results was also larger in the samples of marine origin. Similar vitrinite reflectance values were in general recorded in the whole rock and in the kerogen concentrate. The small deviations of the trend cannot be attributed to the acid treatment involved in kerogen isolation but to reasons related to components identification or to the difficulty to achieve a good polish of samples with high mineral matter content. In samples difficult to polish, vitrinite reflectance was measured on whole rock tended to be lower. The presence or absence of rock fabric affected the selection of the vitrinite population for measurement and this also had an influence in the average value reported and in the scatter of the results. Slightly lower standard deviations were reported for the analyses run on kerogen concentrates. Considering the spectral fluorescence results, it was observed that the {lambda}max presents a shift to higher wavelengths in the kerogen concentrate sample in comparison to the whole-rock sample, thus revealing an influence of preparation methods (acid treatment

  3. A kinetic study of the depyritization of oil shale HCl-kerogen concentrate by Thiobacillus ferrooxidans at different temperatures

    Directory of Open Access Journals (Sweden)

    OLGA CVETKOVIC

    2003-05-01

    Full Text Available The results of kinetic studies of bacterial depyritization of HCl-kerogen concentrate of Aleksinac (Serbia oil shale by the chemolithoautotrophic thionic bacteria Thiobacillus ferrooxidans under discontinuous laboratory conditions at various temperatures (0, 20, 28 and 37°C at a pH of ca. 1.5 are presented in this paper. Low pH prevents the occurrence of the precipitation of iron(III-ion hydrolysis products on the substrate particles and thereby reduces the process efficiency. Bacterial depyritization is developed as per kinetics of the first order. The activation energy which points to a successive mechanism of pyrite biooxidation, was computed from the Arrhenius plot. The biochemical kinetics indicators point to a high affinity of the bacteria toward pyrite but small values of Vmax, which are probably the result of decelerated metabolic processes due to the low pH value of the environment resp. the large difference of the pH between the external medium and the cell interior.

  4. The composition of acids in bitumen and in products from saponification of kerogen: Investigation of their role as connecting kerogen and mineral matrix

    Energy Technology Data Exchange (ETDEWEB)

    Razvigorova, M.; Budinova, T.; Tsyntsarski, B.; Petrova, B. [Bulgarian Academy of Sciences, Institute of Organic Chemistry, 1113 Sofia, Acad. Bonchev Str., bl. 9 (Bulgaria); Ekinci, E. [ISIK University, Kumbaba Mevkii, 34980 Istanbul (Turkey); Atakul, H. [Istanbul Technical University, Department of Chemical Engineering, Maslak, 34469 Istanbul (Turkey)

    2008-11-03

    In order to obtain more information and to understand the nature of relation between organic and mineral matter in oil shales, the compositions of soluble bitumen fractions obtained by extraction from Bulgarian oil shales before and after demineralization with 10% HCl, concentrated HF, and a HF/HCl mixture were investigated. The four extracts were quantitatively examined by IR and {sup 1}H NMR spectroscopy. The investigation of isolated acidic material of the bitumen fractions showed that the fatty acids are present in bitumen fractions as free acids, esters and salts. The amount of free acids in bitumen is very small. The dominant part of bitumen acids is associated with mineral components of the oil shales as well as part of them is included in the mineral matrix, and can be separated only after deep demineralization. The kerogen of the oil shales, obtained after separation of the bitumen fractions and mineral components, was subjected to saponification in order to determine the amount of acids, bound as esters to the kerogen matrix. The major components found were n-carboxylic, {alpha},{omega}-di-carboxylic, and aromatic acids. The connection of kerogen with mineral components is accomplished by the participation of carboxylic and complicated ester bonds. Experimental data for the composition of bitumen acids give evidence that algae and terrestrial materials are initial sources in the formation of soluble organic matter of Bulgarian oil shale. (author)

  5. Rapid quantification of biomarkers during kerogen microscale pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Stott, A.W.; Abbott, G.D. [Fossil Fuels and Environmental Geochemistry NRG, The University, Newcastle-upon-Tyne (United Kingdom)

    1995-02-01

    A rapid, reproducible method incorporating closed system microscale pyrolysis and thermal desorption-gas chromatography/mass spectrometry has been developed and applied to the quantification of sterane biomarkers released during pyrolysis of the Messel oil shale kerogen under confined conditions. This method allows a substantial experimental concentration-time data set to be collected at accurately controlled temperatures, due to the low thermal inertia of the microscale borosilicate glass reaction vessels, which facilitates kinetic studies of biomarker reactions during kerogen microscale pyrolysis

  6. Kerogen-bound and free hopanoic acids in the messel oil shale kerogen.

    Science.gov (United States)

    Abbott, G D; Bashir, F Z; Sugden, M A

    2001-08-01

    The distribution of the free and bound hopanoic acids in both unheated and heated (350 degrees C for 50 h) kerogens, isolated from the Messel oil shale, were analyzed by GC-MS. The bound acids were released by subjecting the kerogen to three different treatments, namely, thermochemolysis in the presence of tetramethylammonium hydroxide (TMAH), as well as basic and acidic hydrolyses. All of these methods gave a series of hopanoic acids ranging from C(30) to C(34), in which the biological 17beta, 21beta(H) configuration is prominent. Both 22R and 22S epimers are present for the C(30) acid, whereas the others are dominated by the sidechain 22R-configuration. Thermochemolysis in the presence of TMAH was the most efficient in releasing kerogen-bound hopanoids. Following pyrolysis, the acids are generated and released into the free fraction with apparent epimerization occurring at C-17, C-21, and C-22. The bound hopanoic acids may be both chemically bonded as well as possibly being physically encapsulated within the macromolecular fraction of sedimentary organic matter. They are therefore either generated by breaking the bonds which bind them to the kerogen or they are released as a result of the macromolecular cage being broken apart. Copyright 2001 Wiley-Liss, Inc.

  7. From cellulose to kerogen: molecular simulation of a geological process.

    Science.gov (United States)

    Atmani, Lea; Bichara, Christophe; Pellenq, Roland J-M; Van Damme, Henri; van Duin, Adri C T; Raza, Zamaan; Truflandier, Lionel A; Obliger, Amaël; Kralert, Paul G; Ulm, Franz J; Leyssale, Jean-Marc

    2017-12-01

    The process by which organic matter decomposes deep underground to form petroleum and its underlying kerogen matrix has so far remained a no man's land to theoreticians, largely because of the geological (Myears) timescale associated with the process. Using reactive molecular dynamics and an accelerated simulation framework, the replica exchange molecular dynamics method, we simulate the full transformation of cellulose into kerogen and its associated fluid phase under prevailing geological conditions. We observe in sequence the fragmentation of the cellulose crystal and production of water, the development of an unsaturated aliphatic macromolecular phase and its aromatization. The composition of the solid residue along the maturation pathway strictly follows what is observed for natural type III kerogen and for artificially matured samples under confined conditions. After expulsion of the fluid phase, the obtained microporous kerogen possesses the structure, texture, density, porosity and stiffness observed for mature type III kerogen and a microporous carbon obtained by saccharose pyrolysis at low temperature. As expected for this variety of precursor, the main resulting hydrocarbon is methane. The present work thus demonstrates that molecular simulations can now be used to assess, almost quantitatively, such complex chemical processes as petrogenesis in fossil reservoirs and, more generally, the possible conversion of any natural product into bio-sourced materials and/or fuel.

  8. Realistic molecular model of kerogen's nanostructure.

    Science.gov (United States)

    Bousige, Colin; Ghimbeu, Camélia Matei; Vix-Guterl, Cathie; Pomerantz, Andrew E; Suleimenova, Assiya; Vaughan, Gavin; Garbarino, Gaston; Feygenson, Mikhail; Wildgruber, Christoph; Ulm, Franz-Josef; Pellenq, Roland J-M; Coasne, Benoit

    2016-05-01

    Despite kerogen's importance as the organic backbone for hydrocarbon production from source rocks such as gas shale, the interplay between kerogen's chemistry, morphology and mechanics remains unexplored. As the environmental impact of shale gas rises, identifying functional relations between its geochemical, transport, elastic and fracture properties from realistic molecular models of kerogens becomes all the more important. Here, by using a hybrid experimental-simulation method, we propose a panel of realistic molecular models of mature and immature kerogens that provide a detailed picture of kerogen's nanostructure without considering the presence of clays and other minerals in shales. We probe the models' strengths and limitations, and show that they predict essential features amenable to experimental validation, including pore distribution, vibrational density of states and stiffness. We also show that kerogen's maturation, which manifests itself as an increase in the sp(2)/sp(3) hybridization ratio, entails a crossover from plastic-to-brittle rupture mechanisms.

  9. Cementation of kerogen-rich marls by alkaline fluids released during weathering of thermally metamorphosed marly sediments. Part II: Organic matter evolution, magnetic susceptibility and metals (Ti, Cr, Fe) at the Khushaym Matruk natural analogue (Central Jordan)

    International Nuclear Information System (INIS)

    Elie, M.; Techer, I.; Trotignon, L.; Khoury, H.; Salameh, E.; Vandamme, D.; Boulvais, P.; Fourcade, S.

    2007-01-01

    Spontaneous combustion, less than 1 Ma ago, affected a 60-m thick sediment pile of bio-micrite at the Khushaym Matruck site (Jordan). The present study shows that three retrograde alteration stages occurred: weathering, thermal stress and oxidative alkaline perturbation. μ-FT-i.r. spectra of isolated kerogens and oxygen index of whole rocks indicate that oxidation of organic matter occurred down to similar to 10 m beneath the metamorphosed zone at Khushaym Matruck. The occurrence of the oxidative weathering bacterially mediated, as suggested by the mass chromatograms of saturated hydrocarbons, can explain high Rock-Eval T max values and low petroliferous potential measured along the sedimentary pile. On the other hand, the thermal extent of combustion events was limited to the first 2 m from the contact. The mean reflectance of 0.20-0.24% and porosity of ca. 50% of the grey clayey bio-micrites indicate that organic matter was very immature and sediments were unconsolidated at the time of the combustion event. Using mineralogy, microscopic analyses of vegetable debris and magnetic susceptibility, a suite of characteristic points corresponding to the thermal imprint can be assessed: (i) x = 0 m, T similar to 1000 degrees C, (ii) x 1 m, T similar to 350 degrees C, (iii) x = 2 m, T similar to 150 degrees C and (iv) x ≥ ∼ 8 m, T similar to 30 degrees C. Paleo-circulation of meteoric groundwater in the 'cement-marbles' generated high-pH fluids that have circulated via fractures and through the matrix porosity of the underlying bio-micrites but have also induced alkaline hydrolysis and oxidative attack of the organic matter. The polysaccharide/lignin ratio derived from mu-FT-i.r. analyses shows that the delignification of vegetable debris and degradation of polysaccharides progressively decline in the indurated zone, which indicates a decrease in the pH of migrating solutions. The latter, also severely oxidized organic matter at 2. 10 and 3.05 m as revealed by the

  10. Molecular characterization of kerogens by mild selective chemical degradation - ruthenium tetroxide oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Boucher, R.J.; Standen, G.; Eglinton, G. (University of Bristol, Bristol (UK). Organic Geochemistry Unit)

    1991-06-01

    Molecular characterization of two kerogen isolates (Messel and Kimmeridge Clay), two kerogen-rich shales (green River and Maoming) and a coal, (Loy Yang) was undertaken using selective chemical degradation with ruthenium tetroxide (RuO{sub 4}). The RuO{sub 4} oxidation gave extracts which were soluble in dichloromethane and contained series of straight chain monocarboxylic acids, {alpha},{omega}-dicarboxylic acids, branched mono- and dicarboxylic acids, isoprenoid and cyclic acids. Straight chain carboxylic acids were predominant (65-87% of quantified chromatogram components for the range of sedimentary organic matter studied), reflecting the major content of polymethylene chains in these kerogens. This mild, oxidative technique serves to differentiate kerogens at a molecular level, thereby supplementing existing conventional chemical, pyrolytic, n.m.r. and other techniques. 39 refs., 3 figs., 5 tabs.

  11. Biological marker distribution in coexisting kerogen, bitumen and asphaltenes in Monterey Formation diatomite, California

    Science.gov (United States)

    Tannenbaum, E.; Ruth, E.; Huizinga, B. J.; Kaplan, I. R.

    1986-01-01

    Organic-rich (18.2%) Monterey Formation diatomite from California was studied. The organic matter consist of 94% bitumen and 6% kerogen. Biological markers from the bitumen and from pyrolysates of the coexisting asphaltenes and kerogen were analyzed in order to elucidate the relationship between the various fractions of the organic matter. While 17 alpha(H), 18 alpha(H), 21 alpha(H)-28,30-bisnorhopane was present in the bitumen and in the pryolysate of the asphaltenes, it was not detected in the pyrolysates of the kerogen. A C40-isoprenoid with "head to head" linkage, however, was present in pyrolysates of both kerogen and asphaltenes, but not in the bitumen from the diatomite. The maturation level of the bitumen, based on the extent of isomerization of steranes and hopanes, was that of a mature oil, whereas the pyrolysate from the kerogen showed a considerably lower maturation level. These relationships indicate that the bitumen may not be indigenous to the diatomite and that it is a mature oil that migrated into the rock. We consider the possibility, however, that some of the 28,30-bisnorhopane-rich Monterey Formation oils have not been generated through thermal degradation of kerogen, but have been expelled from the source rock at an early stage of diagenesis.

  12. Shale kerogen as a macromolecular substance, and the origin of shales. Khimiya i genezis tverd. goryuch. iskopaemykh, trudy i vsesoyuz

    Energy Technology Data Exchange (ETDEWEB)

    Kogerman, P N

    1950-01-01

    Ideas and general laws concerning the chemistry of high polymers were used to study the organic matter of oil shale (Estonian kukersite). The insolubility of kerogen in water, alkali, acids, or organic solvents is similar to two or three dimensional polymers. In an aqueous solution of chloral hydrate, kerogen swells to a certain extent but does not dissolve. This is similar to high polymers. The softening point of kerogen is between 340 and 380/sup 0/C., at which temperature it acquires plastic properties and resembles high-molecular-weight thermoplastics. Kerogen does not distill without decomposition even at reduced pressures and consequently must have a molecular weight above 1,000. Thermal decomposition products of kerogen are mixtures of low-molecular-weight compounds, the composition of which gives little information concerning the original kerogen. Starch, proteins, lignins, and other natural products give similar materials. The average specific gravity of kukersite kerogen is 1.08 and corresponds approximately to that of polymeric hydrocarbons, cellulose ethers, and natural resins such as copal, sandarac, and others. From these facts, kerogen can be considered to be a high-polymeric substance. Most modern geologists hold that marine deposits of microscopic blue-green algae are the parent substances of kerogen. However, other plankton organisms, especially diatoms, may have contributed to the organic material present in kukersite. Modern blue-green algae contain 60 percent proteins, 3 percent fat, 5 percent pentosan, 1 percent cellulose, and 31 percent other carbohydrates. Chemical studies of kerogen, such as halogenation, nitration, permanganate oxidation, and others indicate that kerogen contains both carbon-chain and hetero-chain compounds. The former may have originated from the nonnitrogenous compounds present in the parent blue-green algae, preserved by adsorption on the inorganic portion of kukersite.

  13. Methodological comparison for quantitative analysis of fossil and recently derived carbon in mine soils with high content of aliphatic kerogen

    Czech Academy of Sciences Publication Activity Database

    Vindušková, O.; Sebag, D.; Cailleau, G.; Brus, Jiří; Frouz, J.

    89-90, December (2015), s. 14-22 ISSN 0146-6380 Institutional support: RVO:61389013 Keywords : kerogen * geogenic carbon * soil organic matter Subject RIV: DD - Geochemistry Impact factor: 2.990, year: 2015

  14. Structural Evolution of Kerogen and Bitumen during Thermal Maturation examined by Fourier-Transform Infrared Spectroscopy

    Science.gov (United States)

    Craddock, P. R.; Le Doan, T. V.; Pomerantz, A.

    2014-12-01

    Kerogen—the organic matter that is solid and insoluble in organic solvents—is a key component of organic-rich mudstones. The composition of kerogen affects the storage and transport of hydrocarbons in these unconventional resources and is known to change with thermal maturity. We report here using FTIR spectroscopy, the compositional characteristics of kerogen as a function of thermal maturity, together with the compositional characteristics of the organic phase, bitumen—the organic matter that is solid, but soluble in organic solvents. Kerogen is consumed during thermal maturation, whereas bitumen is an intermediary formed at low maturity from kerogen and consumed at higher maturities in formation of oil and gas. Bitumen relative to kerogen has higher aliphatic content, lower aromatic content, and lower abundance of oxygenated functions. At low maturity (vitrinite reflectance equivalent VRe ~ 0.5-0.9 %), the average length of aliphatic chains in bitumen increases during bitumen formation. At higher thermal maturities (VRe > 1.0-1.3 %), average aliphatic chain length decreases as bitumen is consumed. This evolution contrasts to that in kerogen, where aliphatic chain lengths shorten during all stages of maturation. Breakdown of kerogen appears to be driven by cleavage of oxygen functions at low maturity and removal of aliphatic carbons at higher maturities. These aliphatic-rich fragments may comprise the bitumen, and may in part explain the solubility of bitumen in organic solvents. Bitumen shows evidence of oxidation at low thermal maturity, a phenonemom not documented for kerogen. Bitumen maturation and degradation at higher thermal maturity is driven by cleavage and loss of aliphatic carbons, and is coincident with the maximum generation of oil and gas. The aromatic content of bitumen and of kerogen both increase during maturation as a consequence of the loss of aliphatic carbon. The oil and gas generation potential of the residual organic matter thus

  15. Characterization of Tertiary Catalan lacustrine oil shales: Discovery of extrmely organic sulphur-rich Type I kerogens

    Energy Technology Data Exchange (ETDEWEB)

    Sinninghe Damste, J.S.; Heras, F.X.C. De Las; Bergen, P.F. Van; Leeuw, J.W. De (Delft Univ. of Technology (Netherlands))

    1993-01-01

    The kerogens of three Tertiary Catalan lacustrine oil shales were analyzed by light microscopy, flash pyrolysis-gas chromatography-mass spectrometry, and bulk composition methods (elemental analysis, Rock Eval pyrolysis). Two of the three kerogens (Ribesalbes and Campins) are extremely rich in organic sulfur (atomic S[sub org]/C ratio > 0.04) and hydrogen (atomic ratio H/C ratio > 1.5) and are, consequently, classified as Type I-S kerogens. Very characteristic distribution patterns of flash pyrolysis products (e.g., alkan-9- and -10-ones, alkadienes) of the Ribesalbes kerogen revealed that it is predominantly composed of fossilized organic matter of the freshwater alga Botryococcus braunii. These two findings demonstrate that sulfurization of organic matter may also occur in lacustrine sediments provided that sulfate is supplied by external sources. Data on the third kerogen sample (Cerdanya) suggest that the freshwater alga Pediastrum may contain a (partly) aromatic biomacromolecule that is selectively preserved upon diagenesis. These findings testify to the large variability in palaeodepositional conditions in lacutrine environments. A comparison of the biomarker composition of the extract of the Ribesalbes oil shale with the kerogen composition indicate that biomarkers often cannot be used to assess the major sources of organic matter in such settings. A similar conclusion can be drawn from a comparison of literature data concerning the Messel Oil Shale. 75 refs., 18 figs., 7 tabs.

  16. Characterization of Tertiary Catalan lacustrine oil shales: Discovery of extremely organic sulphur-rich Type I kerogens

    Science.gov (United States)

    Sinninghe Damsté, Jaap S.; de las Heras, F. Xavier C.; van Bergen, Pim F.; de Leeuw, Jan W.

    1993-01-01

    The kerogens of three Tertiary Catalan lacustrine oil shales were analyzed by light microscopy, flash pyrolysis-gas chromatography-mass spectrometry, and bulk composition methods (elemental analysis, Rock Eval pyrolysis). Two of the three kerogens (Ribesalbes and Campins) are extremely rich in organic sulphur (atomic S org/C ratio > 0.04) and hydrogen (atomic ratio H/C ratio > 1.5) and are, consequently, classified as Type I-S kerogens. Very characteristic distribution patterns of flash pyrolysis products (e.g., alkan-9- and -10-ones, alkadienes) of the Ribesalbes kerogen revealed that it is predominantly composed of fossilized organic matter of the freshwater alga Botryococcus braunii. These two findings demonstrate that sulphurization of organic matter may also occur in lacustrine sediments provided that sulphate is supplied by external sources. Data on the third kerogen sample (Cerdanya) suggest that the freshwater alga Pediastrum may contain a (partly) aromatic biomacromolecule that is selectively preserved upon diagenesis. These findings testify to the large variability in palaeodepositional conditions in lacustrine environments. A comparison of the biomarker composition of the extract of the Ribesalbes oil shale with the kerogen composition indicate that biomarkers often cannot be used to assess the major sources of organic matter in such settings. A similar conclusion can be drawn from a comparison of literature data concerning the Messel Oil Shale.

  17. Might dark matter not be concentric with luminous matter

    International Nuclear Information System (INIS)

    Xu Chongming; Lu Tan.

    1986-12-01

    In this paper, an idea on dark matter nonconcentric with luminous matter is proposed. This case could influence the rotation curve of galaxy differently in its different direction. Recently, Rubin and Ford's observation on rotation curve of Hickson 88a has been explained by means of the idea. Some possible observational predictions have also been given. (author)

  18. Chemo-mechanical coupling in kerogen gas adsorption/desorption.

    Science.gov (United States)

    Ho, Tuan Anh; Wang, Yifeng; Criscenti, Louise J

    2018-05-09

    Kerogen plays a central role in hydrocarbon generation in an oil/gas reservoir. In a subsurface environment, kerogen is constantly subjected to stress confinement or relaxation. The interplay between mechanical deformation and gas adsorption of the materials could be an important process for shale gas production but unfortunately is poorly understood. Using a hybrid Monte Carlo/molecular dynamics simulation, we show here that a strong chemo-mechanical coupling may exist between gas adsorption and mechanical strain of a kerogen matrix. The results indicate that the kerogen volume can expand by up to 5.4% and 11% upon CH4 and CO2 adsorption at 192 atm, respectively. The kerogen volume increases with gas pressure and eventually approaches a plateau as the kerogen becomes saturated. The volume expansion appears to quadratically increase with the amount of gas adsorbed, indicating a critical role of the surface layer of gas adsorbed in the bulk strain of the material. Furthermore, gas uptake is greatly enhanced by kerogen swelling. Swelling also increases the surface area, porosity, and pore size of kerogen. Our results illustrate the dynamic nature of kerogen, thus questioning the validity of the current assumption of a rigid kerogen molecular structure in the estimation of gas-in-place for a shale gas reservoir or gas storage capacity for subsurface carbon sequestration. The coupling between gas adsorption and kerogen matrix deformation should be taken into consideration.

  19. Differences in bitumen and kerogen-bound fatty acid fractions during diagenesis and early catagenesis in a maturity series of New Zealand coals

    DEFF Research Database (Denmark)

    Glombitza, Clemens; Mangelsdorf, Kai; Horsfield, Brian

    2016-01-01

    network. Application of the carbon preference index for fatty acids (CPIFA) of bitumen and kerogen-bound acids revealed a linear correlation to the Tmax maturity parameter. This shows that the CPIFA has a clear relation to thermal stability and, thus, reactivity of the buried organic matter....... The difference in slopes of CPIFA vs. Tmax for short and long chain as well as bitumen and kerogen-bound acids may indicate their different degradation susceptibilities. The short chain fatty acids of the bitumen show the highest susceptibility whereas the kerogen-bound long chain fatty acids seem to be most...

  20. Gray Matter Concentration Abnormality in Brains of Narcolepsy Patients

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    Joo, Eun Yeon; Tae, Woo Suk; Kim, Sung Tae; Hong, Seung Bong [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2009-12-15

    To investigate gray matter concentration changes in the brains of narcoleptic patients. Twenty-nine narcoleptic patient with cataplexy and 29 age and sex-matched normal subjects (mean age, 31 years old) underwent volumetric MRIs. The MRIs were spatially normalized to a standard T1 template and subdivided into gray matter, white matter, and cerebrospinal fluid (CSF). These segmented images were then smoothed using a 12-mm full width at half maximum (FWHM) isotropic Gaussian kernel. An optimized voxel-based morphometry protocol was used to analyze brain tissue concentrations using SPM2 (statistical parametric mapping). A one-way analysis of variance was applied to the concentration analysis of gray matter images. Narcoleptics with cataplexy showed reduced gray matter concentration in bilateral thalami, left gyrus rectus, bilateral frontopolar gyri, bilateral short insular gyri, bilateral superior frontal gyri, and right superior temporal and left inferior temporal gyri compared to normal subjects (uncorrected p < 0.001). Furthermore, small volume correction revealed gray matter concentration reduction in bilateral nuclei accumbens, hypothalami, and thalami (false discovery rate corrected p < 0.05). Gray matter concentration reductions were observed in brain regions related to excessive daytime sleepiness, cognition, attention, and memory in narcoleptics with cataplexy

  1. Gray Matter Concentration Abnormality in Brains of Narcolepsy Patients

    International Nuclear Information System (INIS)

    Joo, Eun Yeon; Tae, Woo Suk; Kim, Sung Tae; Hong, Seung Bong

    2009-01-01

    To investigate gray matter concentration changes in the brains of narcoleptic patients. Twenty-nine narcoleptic patient with cataplexy and 29 age and sex-matched normal subjects (mean age, 31 years old) underwent volumetric MRIs. The MRIs were spatially normalized to a standard T1 template and subdivided into gray matter, white matter, and cerebrospinal fluid (CSF). These segmented images were then smoothed using a 12-mm full width at half maximum (FWHM) isotropic Gaussian kernel. An optimized voxel-based morphometry protocol was used to analyze brain tissue concentrations using SPM2 (statistical parametric mapping). A one-way analysis of variance was applied to the concentration analysis of gray matter images. Narcoleptics with cataplexy showed reduced gray matter concentration in bilateral thalami, left gyrus rectus, bilateral frontopolar gyri, bilateral short insular gyri, bilateral superior frontal gyri, and right superior temporal and left inferior temporal gyri compared to normal subjects (uncorrected p < 0.001). Furthermore, small volume correction revealed gray matter concentration reduction in bilateral nuclei accumbens, hypothalami, and thalami (false discovery rate corrected p < 0.05). Gray matter concentration reductions were observed in brain regions related to excessive daytime sleepiness, cognition, attention, and memory in narcoleptics with cataplexy

  2. Kerogen morphology and geochemistry at the Permian-Triassic transition in the Meishan section, South China: Implication for paleoenvironmental variation

    Science.gov (United States)

    Sawada, Ken; Kaiho, Kunio; Okano, Kazuki

    2012-08-01

    Detailed fluorescent microscopic observations and organic geochemical analyses for insoluble sedimentary organic matter (kerogens) are conducted on the end-Permian to earliest Triassic sediments in the Meishan section A of South China. The main objectives of the present study are to reconstruct variations of marine and terrestrial environments, and to evaluate bulk characteristics of terrestrial input in the palaeo-Tethys ocean for the Permian-Triassic boundary (PTB). Most of kerogens in the Meishan section are mainly composed of marine algae-derived amorphous organic matter, while terrestrial plant-derived amorphous organic matter is remarkably dominant in the mass extinction horizon reported previously. The relative abundances of marine organic matter may vary depending on marine production rather than terrestrial input in the palaeo-Tethys associated with changing terrestrial vegetation. We also identified aromatic furans as major compounds in kerogen pyrolysate of all layers. It is possible that sources of aromatic furans with alkyl group, fungi and lichen, proliferated as disaster biota in terrestrial ecosystem through the PTB. Higher abundances of herbaceous organic matter are observed in the layers above the mass extinction horizon. However, the conifer biomarker retene can be identified in kerogen pyrolysates of all layers. These results imply that the productions of herbaceous plants increased as dominant pioneer biota in early stage of recovery for terrestrial ecosystem after its collapse, but also that woody plant potentially continued to be produced in land area throughout the end-Permian and earliest-Triassic.

  3. Rapid estimation of the organic sulphur content of kerogens, coals and asphaltenes by pyrolysis-gas chromatography

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Eglinton, T.I.; Kohnen, M.E.L.; Leeuw, J.W. de

    1990-01-01

    A pyrolysis-gas Chromatographic (py-g.c.) method for estimation of the Sorg/C ratio in kerogens and other forms of sedimentary macromolecular organic matter is described. The method is based upon flash pyrolysis at 610 °C for 10s and areal integration of the FID peaks attributed to

  4. Nature of suspended particulate matter and concentrations of heavy ...

    African Journals Online (AJOL)

    The concentrations of metals in bottom sediment in the Tanzanian waters of Lake Victoria and the nature of suspended particulate matter (SPM) were analysed. The objective of the study was to compare levels of metals in sediment from different locations and to establish their sources. Metal concentrations were higher in ...

  5. Variations in origin and composition of kerogen constituents as revealed by analytical pyrolysis of immature kerogens before and after desulphurization

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Gelin, F.; Harrison, W.; Maxwell, J.R.

    1996-01-01

    Kerogens isolated from nine samples from a single marl bed of the Gessoso-solfifera formation in the Vena del Gesso basin (Upper Miocene, Italy) were treated with CrCl2 and Li/EtNH2 to remove inorganic and organic sulphur, respectively. The untreated and 'desulphurized' (CrCl2 and Li/EtNH2) kerogens

  6. Lyophilization and Reconstitution of Reverse Osmosis Concentrated Natural Organic Matter

    Science.gov (United States)

    Disinfection by-product (DBP) research can be complicated by difficulties in shipping large water quantities and changing natural organic matter (NOM) characteristics over time. To overcome these issues, it is advantageous to have a reliable method for concentrating and preservin...

  7. Pyrolysis-gas chromatographic method for kerogen typing

    Energy Technology Data Exchange (ETDEWEB)

    Larter, S.R.; Douglas, A.G.

    1980-01-01

    The classification of kerogens according to their type and rank is important for the definition of any kerogen assemblage. Whereas optical methods of rank determination are well known, vitrinite reflectance and spore coloration being the most widely accepted chemical methods for typing kerogens are less developed. In this work we show that pyrograms, produced by pyrolyzing microgram quantities of solvent-extracted kerogens, enable not only their characterization in terms of a chromatographic fingerprint but also the production of a numerical type index determined as the ratio of m(+p)-xylene/n-octene (oct-1-ene) in the pyrogram. This index appears to be a close function of kerogen type. Type 3 kerogens (Tissot et al., 1974), including vitrinite, provide a high type index and have pyrolysates dominated by aromatic and phenolic compounds whereas type 1 kerogens provide an aliphatic-rich pyrolysate and consequently a low type index. The type index described here correlates well with microscopic and elemental analysis data and the pyrogram fingerprint provides an additional level of characterization not attainable with other current typing techniques.

  8. Sorption Hysteresis of Light Hydrocarbons and Carbon Dioxide in Shale and Kerogen

    KAUST Repository

    Zhao, Huangjing

    2017-11-20

    We present adsorption and desorption isotherms of methane, ethane, propane, n-butane and iso-butane as well as carbon dioxide for two shales and isolated kerogens determined by a gravimetric method. The sorption measurements of two shales were performed at three different temperatures, 308.15, 323.15, and 338.15 K. For the isolated kerogens, the measurements were conducted at 338.15 K. Methane and ethane sorption isotherms were measured to 35 bar. Carbon dioxide sorption isotherms were studied to 30 bar. Due to the low vapor pressure at room temperature, the sorption isotherms of propane, n-butane and iso-butane were measured to 8, 2, and 2 bar, respectively. The adsorptions of propane, n-butane, and iso-butane were much higher than methane at the highest pressures where the measurements were conducted. The adsorption of n-butane was 10 times higher than methane by mole at 2 bar, followed by iso-butane and propane. Our data show significant adsorption hysteresis in ethane, propane, n-butane and iso-butane. The most pronounced hysteresis was found in n-butane and iso-butane. Significant hysteresis is attributed to the reversible structural changes of kerogens. Dissolution of adsorbates into organic matter may also affect the hysteresis. This is the first report of propane and butane sorption isotherms in shales.

  9. Sorption Hysteresis of Light Hydrocarbons and Carbon Dioxide in Shale and Kerogen

    KAUST Repository

    Zhao, Huangjing; Lai, Zhiping; Firoozabadi, Abbas

    2017-01-01

    We present adsorption and desorption isotherms of methane, ethane, propane, n-butane and iso-butane as well as carbon dioxide for two shales and isolated kerogens determined by a gravimetric method. The sorption measurements of two shales were performed at three different temperatures, 308.15, 323.15, and 338.15 K. For the isolated kerogens, the measurements were conducted at 338.15 K. Methane and ethane sorption isotherms were measured to 35 bar. Carbon dioxide sorption isotherms were studied to 30 bar. Due to the low vapor pressure at room temperature, the sorption isotherms of propane, n-butane and iso-butane were measured to 8, 2, and 2 bar, respectively. The adsorptions of propane, n-butane, and iso-butane were much higher than methane at the highest pressures where the measurements were conducted. The adsorption of n-butane was 10 times higher than methane by mole at 2 bar, followed by iso-butane and propane. Our data show significant adsorption hysteresis in ethane, propane, n-butane and iso-butane. The most pronounced hysteresis was found in n-butane and iso-butane. Significant hysteresis is attributed to the reversible structural changes of kerogens. Dissolution of adsorbates into organic matter may also affect the hysteresis. This is the first report of propane and butane sorption isotherms in shales.

  10. Particulate matter mass concentrations produced from pavement surface abrasion

    Directory of Open Access Journals (Sweden)

    Fullova Dasa

    2017-01-01

    Full Text Available According to the latest findings particulate matter belong to the most significant pollutants in Europe together with ground-level ozone O3 and nitrogen dioxide NO2. Road traffic is one of the main sources of particulate matter. Traffic volume has unpleasant impact on longevity of the pavements and also on the environment. Vehicle motions cause mechanical wearing of the asphalt pavement surface - wearing course by vehicle tyres. The paper deals with abrasion of bituminous wearing courses of pavements. The asphalt mixtures are compared in terms of mechanically separated particulate matter. The samples of asphalt mixtures were rutted in wheel tracking machine. The particulate matter measurements were performed in laboratory conditions. The experimental laboratory measurements make it possible to sample particulates without contamination from exhaust emissions, abraded particles from vehicles, resuspension of road dust and climate affects. The paper offers partial results of measurements on six trial samples of asphalt mixtures with different composition. It presents particulate matter morphology and the comparison of rutted asphalt samples in terms of PM mass concentrations and chemical composition.

  11. Identification and Characterization of Particulate Matter Concentrations at Construction Jobsites

    Directory of Open Access Journals (Sweden)

    Ingrid P. S. Araújo

    2014-11-01

    Full Text Available The identification and characterization of particulate matter (PM concentrations from construction site activities pose major challenges due to the diverse characteristics related to different aspects, such as concentration, particle size and particle composition. Moreover, the characterization of particulate matter is influenced by meteorological conditions, including temperature, humidity, rainfall and wind speed. This paper is part of a broader investigation that aims to develop a methodology for assessing the environmental impacts caused by the PM emissions that arise from construction activities. The objective of this paper is to identify and characterize the PM emissions on a construction site with different aerodynamic diameters (PM2.5, PM10, total suspended particulates (TSP, based on an exploratory study. Initially, a protocol was developed to standardize the construction site selection criteria, laboratory procedures, field sample collection and laboratory analysis. This protocol was applied on a multifamily residential building construction site during three different construction phases (earthworks, superstructure and finishings aimed at measuring and monitoring PM concentrations arising from construction activities. The particulate matter was characterized in different particle sizes. Results showed that the higher TSP emissions arising from construction activities provoked environmental impacts. Some limitations to the results were identified, especially with regards the need for a detailed investigation about the influence of different construction phases on PM emissions. The findings provided significant knowledge about various situations, serving as a basis for improving the existing methodology for particulate material collection on construction sites and the development of future studies on the specific construction site phases.

  12. Release of sulfur- and oxygen-bound components from a sulfur-rich kerogen during simulated maturation by hydrous pyrolysis

    Science.gov (United States)

    Putschew, A.; Schaeffer-Reiss, C.; Schaeffer, P.; Koopmans, M.P.; De Leeuw, J. W.; Lewan, M.D.; Sinninghe, Damste J.S.; Maxwell, J.R.

    1998-01-01

    An immature sulfur-rich marl from the Gessosso-solfifera Formation of the Vena del Gesso Basin (Messinian, Italy) has been subjected to hydrous pyrolysis (160 to 330??C) to simulate maturation under natural conditions. The kerogen of the unheated and heated samples was isolated and the hydrocarbons released by selective chemical degradation (Li/EtNH2 and HI/LiAIH4) were analysed to allow a study of the fate of sulfur- and oxygen-bound species with increasing temperature. The residues from the chemical treatments were also subjected to pyrolysis-GC to follow structural changes in the kerogens. In general, with increasing hydrous pyrolysis temperature, the amounts of sulfide- and ether-bound components in the kerogen decreased significantly. At the temperature at which the generation of expelled oil began (260??C), almost all of the bound components initially present in the unheated sample were released from the kerogen. Comparison with an earlier study of the extractable organic matter using a similar approach and the same samples provides molecular evidence that, with increasing maturation, solvent-soluble macromolecular material was initially released from the kerogen, notably as a result of thermal cleavage of weak Carbon-heteroatom bonds (sulfide, ester, ether) even at temperatures as low as 220??C. This solvent-soluble macromolecular material then underwent thermal cleavage to generate hydrocarbons at higher temperatures. This early generation of bitumen may explain the presence of unusually high amounts of extractable organic matter of macromolecular nature in very immature S-rich sediments.

  13. Laboratory Measurements of Particulate Matter Concentrations from Asphalt Pavement Abrasion

    Directory of Open Access Journals (Sweden)

    Fullová Daša

    2016-12-01

    Full Text Available The issue of emissions from road traffic is compounded by the fact that the number of vehicles and driven kilometres increase each year. Road traffic is one of the main sources of particulate matter and traffic volume is still increasing and has unpleasant impact on longevity of the pavements and the environment. Vehicle motions cause mechanical wearing of the asphalt pavement surface - wearing course by vehicle tyres. The contribution deals with abrasion of bituminous wearing courses of pavements. The asphalt mixtures of wearing courses are compared in terms of mechanically separated particulate matter. The samples of asphalt mixtures were rutted in wheel tracking machine. The particulate matter measurements were performed in laboratory conditions. The experimental laboratory measurements make it possible to sample particulates without contamination from exhaust emissions, abraded particles from vehicles, resuspension of road dust and climate affects. The contribution offers partial results of measurements on six trial samples of asphalt mixtures with different composition. It presents particulate matter morphology and the comparison of rutted asphalt samples in terms of PM mass concentrations and chemical composition.

  14. Spatial and temporal variability in urban fine particulate matter concentrations

    International Nuclear Information System (INIS)

    Levy, Jonathan I.; Hanna, Steven R.

    2011-01-01

    Identification of hot spots for urban fine particulate matter (PM 2.5 ) concentrations is complicated by the significant contributions from regional atmospheric transport and the dependence of spatial and temporal variability on averaging time. We focus on PM 2.5 patterns in New York City, which includes significant local sources, street canyons, and upwind contributions to concentrations. A literature synthesis demonstrates that long-term (e.g., one-year) average PM 2.5 concentrations at a small number of widely-distributed monitoring sites would not show substantial variability, whereas short-term (e.g., 1-h) average measurements with high spatial density would show significant variability. Statistical analyses of ambient monitoring data as a function of wind speed and direction reinforce the significance of regional transport but show evidence of local contributions. We conclude that current monitor siting may not adequately capture PM 2.5 variability in an urban area, especially in a mega-city, reinforcing the necessity of dispersion modeling and methods for analyzing high-resolution monitoring observations. - Highlights: →Fine particulate matter (PM 2.5 ) hot spots are hard to identify in urban areas. → Literature conclusions about PM 2.5 hot spots depend on study design and methods. → Hot spots are more likely for short-term concentrations at high spatial density. → Statistical methods illustrate local source impacts beyond regional transport. → Dispersion models and high-resolution monitors are both needed to find hot spots. - Fine particulate matter can vary spatially within large urban areas, in spite of the significant contribution from regional atmospheric transport.

  15. Role of NSO compounds during primary cracking of a Type II kerogen and a Type III lignite

    Science.gov (United States)

    Behar, F.; Lorant, F.; Lewan, M.

    2008-01-01

    The aim of this work is to follow the generation of NSO compounds during the artificial maturation of an immature Type II kerogen and a Type III lignite in order to determine the different sources of the petroleum potential during primary cracking. Experiments were carried out in closed system pyrolysis in the temperature range from 225 to 350 ??C. Two types of NSOs were recovered: one is soluble in n-pentane and the second in dichloromethane. A kinetic scheme was optimised including both kerogen and NSO cracking. It was validated by complementary experiments carried out on isolated asphaltenes generated from the Type II kerogen and on the total n-pentane and DCM extracts generated from the Type III lignite. Results show that kerogen and lignite first decompose into DCM NSOs with minor generation of hydrocarbons. Then, the main source of petroleum potential originates from secondary cracking of both DCM and n-pentane NSOs through successive decomposition reactions. These results confirm the model proposed by Tissot [Tissot, B., 1969. Premie??res donne??es sur les me??canismes et la cine??tique de la formation du pe??trole dans les bassins se??dimentaires. Simulation d'un sche??ma re??actionnel sur ordinateur. Oil and Gas Science and Technology 24, 470-501] in which the main source of hydrocarbons is not the insoluble organic matter, but the NSO fraction. As secondary cracking of the NSOs largely overlaps that of the kerogen, it was demonstrated that bulk kinetics in open system is a result of both kerogen and NSO cracking. Thus, another kinetic scheme for primary cracking in open system was built as a combination of kerogen and NSO cracking. This new kinetic scheme accounts for both the rate and amounts of hydrocarbons generated in a closed pyrolysis system. Thus, the concept of successive steps for hydrocarbon generation is valid for the two types of pyrolysis system and, for the first time, a common kinetic scheme is available for extrapolating results to natural

  16. Extensive Sorption of Organic Compounds to Black Carbon, Coal and Kerogen in Sediments and Soils: Mechanisms and Consequences for Distribution, Bioaccumulation and Biodegradation (Critical Review)

    NARCIS (Netherlands)

    Cornelissen, G.; Gustafsson, O.; Bucheli, T.D.; Jonker, M.T.O.; Koelmans, A.A.; Noort, van P.C.M.

    2005-01-01

    Evidence is accumulating that sorption of organic chemicals to soils and sediments can be described by "dual-mode sorption": absorption in amorphous organic matter (AOM) and adsorption to carbonaceous materials such as black carbon (BC), coal, and kerogen, collectively termed "carbonaceous

  17. Fitting the Probability Distribution Functions to Model Particulate Matter Concentrations

    International Nuclear Information System (INIS)

    El-Shanshoury, Gh.I.

    2017-01-01

    The main objective of this study is to identify the best probability distribution and the plotting position formula for modeling the concentrations of Total Suspended Particles (TSP) as well as the Particulate Matter with an aerodynamic diameter<10 μm (PM 10 ). The best distribution provides the estimated probabilities that exceed the threshold limit given by the Egyptian Air Quality Limit value (EAQLV) as well the number of exceedance days is estimated. The standard limits of the EAQLV for TSP and PM 10 concentrations are 24-h average of 230 μg/m 3 and 70 μg/m 3 , respectively. Five frequency distribution functions with seven formula of plotting positions (empirical cumulative distribution functions) are compared to fit the average of daily TSP and PM 10 concentrations in year 2014 for Ain Sokhna city. The Quantile-Quantile plot (Q-Q plot) is used as a method for assessing how closely a data set fits a particular distribution. A proper probability distribution that represents the TSP and PM 10 has been chosen based on the statistical performance indicator values. The results show that Hosking and Wallis plotting position combined with Frechet distribution gave the highest fit for TSP and PM 10 concentrations. Burr distribution with the same plotting position follows Frechet distribution. The exceedance probability and days over the EAQLV are predicted using Frechet distribution. In 2014, the exceedance probability and days for TSP concentrations are 0.052 and 19 days, respectively. Furthermore, the PM 10 concentration is found to exceed the threshold limit by 174 days

  18. Particulate Matter Concentrations in East Oakland's High Street Corridor

    Science.gov (United States)

    Lei, P.; Jackson, J.; Lewis, R.; Marigny, A.; Mitchell, J. D.; Nguyen, R.; Philips, B.; Randle, D.; Romero, D.; Spears, D.; Telles, C.; Weissman, D.

    2012-12-01

    Particulate matter (PM) is a complex mixture of small solid pieces and/or liquid droplets in the air. High concentrations of PM can pose a serious health hazard because inhalation can result in breathing problems and/or aggravate asthma. Long term exposure can increase the likelihood of respiratory problems like asthma and emphysema as well as cancer. The smaller the particles, the deeper they can get into the respiratory system. For this reason, the smallest particles, those smaller than 2.5 micrometers in diameter (PM2.5), are the most dangerous. PM2.5 is largely emitted from motor vehicles burning fuels that don't break down fully. Our research team investigated the levels of PM2.5 as well as particles smaller than 10 micrometers (PM10) and total suspended particulate (TSP) along the northeast-southwest trending High Street Corridor, near Fremont High School in East Oakland, California. Using the Aerocet 531 mass particle counter, team members walked through neighborhoods and along major roads within a 1 mile radius of Fremont High School. The Aerocet 531 recorded two minute average measurements of all the relevant PM sizes, which are reported in mg/m3. Measurements were consistently taken in the morning, between 8:30 and 11:30 am. Preliminary results indicate maximum readings of all PM sizes at sites that are in close proximity to a major freeway (Interstate-880). These results support our initial hypothesis that proximity to major roads and freeways, especially those with high diesel-fuel burning truck traffic, would be the primary factor affecting PM concentration levels. Preliminary median and maximum readings all suggest particulate matter levels below what the EPA would consider unhealthy or risky.

  19. Chitin: 'Forgotten' Source of Nitrogen: From Modern Chitin to Thermally Mature Kerogen: Lessons from Nitrogen Isotope Ratios

    Science.gov (United States)

    Schimmelmann, A.; Wintsch, R.P.; Lewan, M.D.; DeNiro, M.J.

    1998-01-01

    Chitinous biomass represents a major pool of organic nitrogen in living biota and is likely to have contributed some of the fossil organic nitrogen in kerogen. We review the nitrogen isotope biogeochemistry of chitin and present preliminary results suggesting interaction between kerogen and ammonium during thermal maturation. Modern arthropod chitin may shift its nitrogen isotope ratio by a few per mil depending on the chemical method of chitin preparation, mostly because N-containing non-amino-sugar components in chemically complex chitin cannot be removed quantitatively. Acid hydrolysis of chemically complex chitin and subsequent ion-chromatographic purification of the "deacetylated chitin-monomer" D-glucosamine (in hydrochloride form) provides a chemically well-defined, pure amino-sugar substrate for reproducible, high-precision determination of ??15N values in chitin. ??15N values of chitin exhibited a variability of about one per mil within an individual's exoskeleton. The nitrogen isotope ratio differed between old and new exoskeletons by up to 4 per mil. A strong dietary influence on the ??15N value of chitin is indicated by the observation of increasing ??15N values of chitin from marine crustaceans with increasing trophic level. Partial biodegradation of exoskeletons does not significantly influence ??15N values of remaining, chemically preserved amino sugar in chitin. Diagenesis and increasing thermal maturity of sedimentary organic matter, including chitin-derived nitrogen-rich moieties, result in humic compounds much different from chitin and may significantly change bulk ??15N values. Hydrous pyrolysis of immature source rocks at 330??C in contact with 15N-enriched NH4Cl, under conditions of artificial oil generation, demonstrates the abiogenic incorporation of inorganic nitrogen into carbon-bound nitrogen in kerogen. Not all organic nitrogen in natural, thermally mature kerogen is therefore necessarily derived from original organic matter, but may

  20. Characterizing temporal changes of agricultural particulate matter number concentrations

    Science.gov (United States)

    Docekal, G. P.; Mahmood, R.; Larkin, G. P.; Silva, P. J.

    2017-12-01

    It is widely accepted among literature that particulate matter (PM) are of detriment to human health and the environment as a whole. These effects can vary depending on the particle size. This study examines PM size distributions and number concentrations at a poultry house. Despite much literature on PM concentrations at agricultural facilities, few studies have looked at the size distribution of particles at such facilities from the nucleation up through the coarse mode. Two optical particle counters (OPCs) were placed, one inside of a chicken house, and one on the outside of an exhaust fan to determine particle size distributions. In addition, a scanning mobility particle sizer (SMPS) and aerodynamic particle sizer (APS) sampled poultry house particles to give sizing information from a full size range of 10 nm - 20 mm. The data collected show several different types of events where observed size distributions changed. While some of these are due to expected dust generation events producing coarse mode particles, others suggest particle nucleation and accumulation events at the smaller size ranges that also occurred. The data suggest that agricultural facilities have an impact one the presence of PM in the environment beyond just generation of coarse mode dust. Data for different types of size distribution changes observed will be discussed.

  1. Experimental simulation of the natural transformation of kerogen

    Energy Technology Data Exchange (ETDEWEB)

    Monin, J C [Institut Francais du Petrole, Rueil-Malmaison, France; Durand, B; Vandenbroucke, M; Huc, A Y

    1980-01-01

    Analytical techniques such as elemental analysis, infrared spectroscopy, ESR, dark-field electron microscopy and reflectance analysis applied to kerogens enables the geochemist to describe how they evolve at depth. Simulation of this evolution is obtained by the temperature-programmed heating of immature samples in a stream of inert gas. Comparison of naturally occurring samples at increasing stages of maturation, and artificially matured samples demonstrates that this simulation generally reproduces the overall characteristics of evolution at depth. However, agreement is better for hydrogen-rich than for oxygen-rich kerogens. In fact, oxygen is eliminated in nature, and in the laboratory, by different mechanisms. In nature, elimination takes place mainly at the beginning of burial. Temperatures used in the laboratory are necessarily much higher and appear to cause secondary reactions which favor water formation. Elimination of hydrogen occurs, during natural maturation, at greater depths and temperatures - i.e., in the oil and gas formation zone. Therefore, laboratory simulation is better for kerogens which have already reached the oil formation stage. Hydrocarbons released by natural and laboratory-simulated maturation are compared. Although quantities and distributions are different, similarities exist which can be used, to a first approximation, to predict the distribution of hydrocarbons obtained from naturally-evolving kerogens.

  2. Particulate Matter Concentration Levels in South Central Richmond, California (Invited)

    Science.gov (United States)

    Bonner, B.; Byias, C.; Cuff, K. E.; Diaz, J.; Love, K.; Marks-Block, T.; McLane, F.; Mollique, Z.; Montes, E.; Ross, R.; Washington, B.

    2009-12-01

    South Central Richmond, California is the home of one of the nation’s most innovative green workforce training centers, Richmond BUILD - Green Jobs Training facility. A near constant stream of young people engaged in training activities, instructors, invited guests, and journalists of various ages can be seen moving in and out of the facility nearly every day of the week throughout a given year. Additionally, the comings and goings of young children and adults associated with a mid-sized elementary school just north of the facility contributes to the general area’s substantial human traffic. Unfortunately, however, a major highway, Interstate 580, a major thoroughfare, 23rd Street and a railway line operated by Burlington Northern Santa Fe, Union Pacific, and the Richmond Pacific Railroad frame the triangular area within which these two sites are situated. In addition, a major petrochemical complex and several shipping facilities are located less than three kilometers away north and west of this area. As part of a general assessment of air quality in this heavily human traveled area, we conducted a study of particulate matter (PM) concentrations over a five-month period beginning in August of 2009. Measurements were made at a variety of locations, and results were used to map the spatial distribution of PM of various sizes. Regions of high concentration levels were identified, and these particular areas then were monitored over time. Preliminary results of our study indicate that regions with high concentrations are consistent across the range of particle sizes measured, which suggests a common source for PM found in the study area. As these regions are located close to a major thoroughfare and railway line, we believe that diesel-burning vehicles are major contributors to the PM levels found in the study area. Time series results suggest a fairly strong correlation between higher than average PM concentrations and abnormally high wind gusts. On days when wind

  3. Study of Kerogen Maturity using Transmission Fourier Transform Infrared Spectroscopy (FTIR)

    Science.gov (United States)

    Dang, S. T.

    2014-12-01

    Maturity of kerogen in shale governs the productivity and generation hydrocarbon type. There are generally two accepted methods to measure kerogen maturity; one is the measurement of vitrinite reflectance, %Ro, and another is the measurement of Tmax through pyrolysis. However, each of these techniques has its own limits; vitrinite reflectance measurement cannot be applied to marine shale and pre-Silurian shales, which lack plant materials. Furthermore, %Ro, requires the isolation and identification of vitrinite macerals and statistical measurements of at least 50 macerals. Tmax measurement is questionable for mature and post-mature samples. In addition, there are questions involving the effects of solvents on Tmax determinations. Fourier Transmission Infrared Spectroscopy, FTIR, can be applied for both qualitative and quantitative assessment on organics maturity in shale. The technique does not require separating organic matter or identifying macerals. A CH2/CH3 index, RCH, calculated from FTIR spectra is more objective than other measurements. The index increases with maturity (both natural maturation and synthetic maturation through hydrous and dry pyrolysis). The new maturity index RCH can be calibrated to vitrinite reflectance which allows the definition of the following values for levels of maturity: 1) immature—RCH > 1.6±0.2; 2) oil window-- 1.6±0.2 1.3±0.3; 3) wet gas window--1.3±0.3 1.13±0.05; and 4) dry gas window RCH < 1.13±0.05.

  4. Analysis of the kerogen of oil shales

    Energy Technology Data Exchange (ETDEWEB)

    Quass, F W; Down, A L

    1939-01-01

    Comments are given on the method developed by F. W. Quass for reducing the amount of mineral matter present in certain coals and oil shales (torbanites). The method consisted of grinding oil shale with water in a porcelain ball mill in the presence of oil. The oil formed a paste with the carbonaceous material, and a greater portion of the mineral matter remained suspended in the water and was separated. Ultimate analyses of the enriched samples indicated that the percent of carbon was higher, the percent of hydrogen and oxygen was lower, and the ratio of carbon to hydrogen and carbon to oxygen increased in the enriched samples.

  5. Paleovegetation changes recorded by n-alkyl lipids bound in macromolecules of plant fossils and kerogens from the Cretaceous sediments in Japan

    Science.gov (United States)

    Miyata, Y.; Sawada, K.; Nakamura, H.; Takashima, R.; Takahashi, M.

    2014-12-01

    Resistant macromolecules composing living plant tissues tend to be preserved through degradation and diagenesis, hence constituate major parts of sedimentary plant-derived organic matter (kerogen), and their monomer compositions vary widely among different plant taxa, organs and growth stages. Thus, analysis of such macromolecule may serve as new technique for paleobotanical evaluation distinctive from classical paleobotnical studies depends on morphological preservation of fossils. In the present study, we analyzed plant fossils and kerogens in sediments from the Cretaceous strata in Japan to examine chemotaxonomic characteristics of fossil macromolecules and to reconstruct paleovegetation change by kerogen analysis. The kerogens were separated from the powdered sediments of Cretaceous Yezo Group, Hokkaido, Japan. All kerogens have been confirmed to be mostly originated from land plant tissues by microscopic observation. Mummified angiosperm and gymnosperm fossil leaves were separated from carbonaceous sandstone of the Cretaceous Ashizawa Formation, Futaba Group. The kerogens and plant fossils were extracted with methanol and dichloromethane, and were subsequently refluxed under 110°C to remove free compounds completely. The residues are hydrolyzed by KOH/methanol under 110°C. These released compounds are analyzed by GC-MS. As main hydrolyzed products (ester-bound molecular units) from all kerogens, C10-C28 n-alkanoic acids and C10-C30 n-alkanols were detected. Recent studies on the hydrolysis products of plant tissues suggested the long chain (>C20) n-alkanols were predominantly abundant in deciduous broadleaved angiosperms. Correspondingly, the stratigraphic variation of the ratios of long chain (>C20) n-alkanols to fatty acids was concordant with the variation of angiosperm/gymnosperm ratios recorded by land plant-derived terpenoid biomarkers. In addition, we found that the long chain n-alkanols/fatty acids ratio in the angiosperm fossil leaf was

  6. Concentrated dark matter: Enhanced small-scale structure from codecaying dark matter

    OpenAIRE

    Dror, Jeff A.; Kuflik, Eric; Melcher, Brandon; Watson, Scott

    2018-01-01

    We study the cosmological consequences of codecaying dark matter—a recently proposed mechanism for depleting the density of dark matter through the decay of nearly degenerate particles. A generic prediction of this framework is an early dark matter dominated phase in the history of the Universe, that results in the enhanced growth of dark matter perturbations on small scales. We compute the duration of the early matter dominated phase and show that the perturbations are robust against washout...

  7. Contribution de la géochimie organique à une esquisse paléoécologique des shistes bitumeux du Toarcien de l'Est du bassin de Paris. Etude de la matière organique insoluble (kérogènes Contribution of Organic Geochemistry to a Paleoecological Sketch of Toarcian Oil Shales in the Eastern Paris Basin. Analysis of Insoluble Organic Matter (Kerogens

    Directory of Open Access Journals (Sweden)

    Huc A. Y.

    2006-11-01

    Full Text Available L'étude des kérogènes des schistes cartons du Toarcien inférieur du bassin de Paris au niveau de l'affleurement oriental (du Luxembourg au Morvan confirme l'homogénéité globale de la matière organique dans cette formation. Il s'agit d'une matière organique d'origine marine autochtone. Cependant l'existence de fluctuations (de faible amplitude répondant à une logique géographique conforte la notion de provinces géochimiques dans ce bassin, telle qu'elle avait été définie à l'occasion de l'étude de la fraction soluble (CHCIsJ. La distinction entre une province nord (Lorraine et une province sud (Avallonais,Haute-Saône, Haute-Marne pourrait être imputable à un apport détritique plus sensible dans la partie septentrionale du bassin et/ou aux conditions de milieu ayant régné au moment du dépôt. The present study of kerogens isolated from early Toorcion shales sompled on the eastern out-trop of the Paris Basin (from Luxembourg to Morvan verifies the overall homogeneity of the organic matter in this formation. This organic matter is of autoch thonous marine origin. However, the occurrence of small variations related to different geogrophical locations reinforces the concept of geochemical provinces in this basin as revealed by a previous analysis of the chloroform extracts. Differences between a northern province (Lorraine and a southern province (Avallon area, Haute-Saône, Haute-Marne could be interpreted as the consequence of a more important detrital input in the northern part of the basin and/or of different environmental conditions at the time of deposition.

  8. Trace metals concentration assessment in urban particulate matter ...

    African Journals Online (AJOL)

    This study was conducted to investigate the distribution and correlation of selected trace elements (Ca, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in Yenagoa, Bayelsa State and its environs. Air particulate matter was collected gravimetrically at five stations (using a high volume portable SKC air check MTXSidekickair sampler ...

  9. Detecting Kerogen as a Biosignature Using Colocated UV Time-Gated Raman and Fluorescence Spectroscopy.

    Science.gov (United States)

    Shkolyar, Svetlana; Eshelman, Evan J; Farmer, Jack D; Hamilton, David; Daly, Michael G; Youngbull, Cody

    2018-04-01

    The Mars 2020 mission will analyze samples in situ and identify any that could have preserved biosignatures in ancient habitable environments for later return to Earth. Highest priority targeted samples include aqueously formed sedimentary lithologies. On Earth, such lithologies can contain fossil biosignatures as aromatic carbon (kerogen). In this study, we analyzed nonextracted kerogen in a diverse suite of natural, complex samples using colocated UV excitation (266 nm) time-gated (UV-TG) Raman and laser-induced fluorescence spectroscopies. We interrogated kerogen and its host matrix in samples to (1) explore the capabilities of UV-TG Raman and fluorescence spectroscopies for detecting kerogen in high-priority targets in the search for possible biosignatures on Mars; (2) assess the effectiveness of time gating and UV laser wavelength in reducing fluorescence in Raman spectra; and (3) identify sample-specific issues that could challenge rover-based identifications of kerogen using UV-TG Raman spectroscopy. We found that ungated UV Raman spectroscopy is suited to identify diagnostic kerogen Raman bands without interfering fluorescence and that UV fluorescence spectroscopy is suited to identify kerogen. These results highlight the value of combining colocated Raman and fluorescence spectroscopies, similar to those obtainable by SHERLOC on Mars 2020, to strengthen the confidence of kerogen detection as a potential biosignature in complex natural samples. Key Words: Raman spectroscopy-Laser-induced fluorescence spectroscopy-Mars Sample Return-Mars 2020 mission-Kerogen-Biosignatures. Astrobiology 18, 431-453.

  10. An in situ FTIR step-scan photoacoustic investigation of kerogen and minerals in oil shale.

    Science.gov (United States)

    Alstadt, Kristin N; Katti, Dinesh R; Katti, Kalpana S

    2012-04-01

    Step-scan photoacoustic infrared spectroscopy experiments were performed on Green River oil shale samples obtained from the Piceance Basin located in Colorado, USA. We have investigated the molecular nature of light and dark colored areas of the oil shale core using FTIR photoacoustic step-scan spectroscopy. This technique provided us with the means to analyze the oil shale in its original in situ form with the kerogen-mineral interactions intact. All vibrational bands characteristic of kerogen were found in the dark and light colored oil shale samples confirming that kerogen is present throughout the depth of the core. Depth profiling experiments indicated that there are changes between layers in the oil shale molecular structure at a length scale of micron. Comparisons of spectra from the light and dark colored oil shale core samples suggest that the light colored regions have high kerogen content, with spectra similar to that from isolated kerogen, whereas, the dark colored areas contain more mineral components which include clay minerals, dolomite, calcite, and pyrite. The mineral components of the oil shale are important in understanding how the kerogen is "trapped" in the oil shale. Comparing in situ kerogen spectra with spectra from isolated kerogen indicate significant band shifts suggesting important nonbonded molecular interactions between the kerogen and minerals. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Carbonate petrography, kerogen distribution, and carbon and oxygen isotope variations in an early Proterozoic transition from limestone to iron-formation deposition, Transvaal Supergroup, South Africa

    Science.gov (United States)

    Beukes, N. J.; Klein, C.; Kaufman, A. J.; Hayes, J. M.

    1990-01-01

    sparites are most depleted in 13C. Carbonates in oxide-rich iron-formations are more depleted in 13C than those in siderite-rich iron-formation whereas the kerogens in oxide banded iron-formations (BIF) are more enriched. This implies that the siderite-rich iron-formations were not derived from oxide-rich iron-formation through reduction of ferric iron by organic matter. Organic matter oxidation by ferric iron did, however, decrease the abundance of kerogen in oxide-rich iron-formation and led to the formation of isotopically very light sparry carbonates. Siderite and calcmicrosparite both represent recrystallized primary micritic precipitates but differ in their 13C composition, with the siderites depleted in 13C by 4.6 per mil on average relative to calcmicrosparite. This means that the siderites were precipitated from water with dissolved inorganic carbon depleted in 13C by about 9 per mil relative to that from which the limestones precipitated. This implies an ocean system stratified with regard to total carbonate, with the deeper water, from which siderite-rich iron-formation formed, depleted in 13C. Iron-formations were deposited in areas of very low organic matter supply. Depletion of 13C may, therefore, derive not from degradation of organic matter but from hydrothermal activity, a conclusion which is supported by 18O composition of the carbonate minerals and trace element and rare earth element (REE) compositions of the iron-formations.

  12. Sorption of phenanthrene and benzene on differently structural kerogen: Important role of micropore-filling

    International Nuclear Information System (INIS)

    Zhang, Yulong; Ma, Xiaoxuan; Ran, Yong

    2014-01-01

    Shale was thermally treated to obtain a series of kerogen with varied maturation. Their chemical, structural and porous properties were related to the sorption and/or desorption behaviors of phenanthrene and benzene. As the treatment temperature increases, aliphatic and carbonyl carbon of the kerogen samples decrease, while their aromaticity and maturation increase. Meanwhile, the isothermal nonlinearity of phenanthrene and benzene increases whereas the sorption capacity and micropore adsorption volumes (V o,d ) initially increase and then decrease. The V o,d of benzene is significantly correlated with, but higher than that of phenanthrene, suggesting similar micropore filling mechanism and molecular sieve effect. The benzene desorption exhibits hysteresis, which is related to the pore deformation of the kerogen and the entrapment of solute in the kerogen matrix. The V o,d of phenanthrene and benzene on the kerogen samples accounts for 23–46% and 36–65% of the maximum sorption volumes, respectively, displaying the importance of the micropore filling. -- Highlights: • The microporosity estimated by benzene vapor differs greatly from that by N 2 . • The micropore volume changes with kerogen maturation. • The phenanthrene or benzene sorption is related to the microporosity of kerogen. • Higher adsorption volume for benzene than for phenanthrene suggests molecular sieve effect. • The pore-filling plays an important role in the sorption of phenanthrene and benzene. -- The sorption behaviors of benzene and phenanthrene are related to the microporosity of the differently matured kerogen, indicating the importance of pore-filling

  13. Model representations of kerogen structures: An insight from density functional theory calculations and spectroscopic measurements.

    Science.gov (United States)

    Weck, Philippe F; Kim, Eunja; Wang, Yifeng; Kruichak, Jessica N; Mills, Melissa M; Matteo, Edward N; Pellenq, Roland J-M

    2017-08-01

    Molecular structures of kerogen control hydrocarbon production in unconventional reservoirs. Significant progress has been made in developing model representations of various kerogen structures. These models have been widely used for the prediction of gas adsorption and migration in shale matrix. However, using density functional perturbation theory (DFPT) calculations and vibrational spectroscopic measurements, we here show that a large gap may still remain between the existing model representations and actual kerogen structures, therefore calling for new model development. Using DFPT, we calculated Fourier transform infrared (FTIR) spectra for six most widely used kerogen structure models. The computed spectra were then systematically compared to the FTIR absorption spectra collected for kerogen samples isolated from Mancos, Woodford and Marcellus formations representing a wide range of kerogen origin and maturation conditions. Limited agreement between the model predictions and the measurements highlights that the existing kerogen models may still miss some key features in structural representation. A combination of DFPT calculations with spectroscopic measurements may provide a useful diagnostic tool for assessing the adequacy of a proposed structural model as well as for future model development. This approach may eventually help develop comprehensive infrared (IR)-fingerprints for tracing kerogen evolution.

  14. Geochemical characterisation of kerogen from the Boom Clay Formation (Mol, Belgium) and evolution under different thermal stress

    International Nuclear Information System (INIS)

    Deniau, I.

    2002-12-01

    The Boom clay formation in Belgium has been chosen as test site for the disposal of high level radioactive wastes. The organic matter present in the clay (kerogen) is sensible to the thermal stress and can generate a huge number of gaseous and liquid compounds leading to local pH changes and to fracturing processes. In particular, some polar compounds can complex radionuclides. The samples analyzed in this work were taken in the underground laboratory of Mol at a 223 m depth. They have been analyzed in detail using geochemical methods (Rock-Eval pyrolysis, element analysis, transmission and scanning electron microscopy), spectroscopic methods (Fourier transformation infrared spectroscopy, solid state 13 C NMR, Raman) and pyrolytic methods (off-line, on-line and in sealed tubes combined with coupled CG/SM analyses). The study of a representative sample of this formation has permitted to characterize the organic matter at the molecular scale, to determine its fossilization mechanisms and the nature of the organic compounds trapped inside the kerogen. The organic matter of the Boom clays comes mainly from phyto-planktonic matter with an important contribution of terrestrial and bacterial matter. The degradation-recondensation played an important role in its preservation but the presence of numerous oxygenated molecules implies that oxidative incorporation also participated to this preservation. Finally, various products (hydrocarbons, oxygenated and nitrogenous polar compounds) trapped in significant amount inside the macro-molecular structure are released under a relatively weak thermal stress. Moreover several small polar organic molecules are released and can play a significant role in the retention or migration of radionuclides inside the geologic barrier. A sample submitted to a in-situ thermal stress of 80 deg. C during 5 years (Cerberus experiment) do not show any significant change in its kerogen structure with respect to the non-heated reference sample

  15. Satellite constraints on surface concentrations of particulate matter

    Science.gov (United States)

    Ford Hotmann, Bonne

    Because of the increasing evidence of the widespread adverse effects on human health from exposure to poor air quality and the recommendations of the World Health Organization to significantly reduce PM2.5 in order to reduce these risks, better estimates of surface air quality globally are required. However, surface measurements useful for monitoring particulate exposure are scarce, especially in developing countries which often experience the worst air pollution. Therefore, other methods are necessary to augment estimates in regions with limited surface observations. The prospect of using satellite observations to infer surface air quality is attractive; however, it requires knowledge of the complicated relationship between satellite-observed aerosol optical depth (AOD) and surface concentrations. This dissertation explores how satellite observations can be used in conjunction with a chemical transport model (GEOS-Chem) to better understand this relationship. First, we investigate the seasonality in aerosols over the Southeastern United States using observations from several satellite instruments (MODIS, MISR, CALIOP) and surface network sites (IMPROVE, SEARCH, AERONET). We find that the strong summertime enhancement in satellite-observed aerosol optical depth (factor 2-3 enhancement over wintertime AOD) is not present in surface mass concentrations (25-55% summertime enhancement). Goldstein et al. [2009] previously attributed this seasonality in AOD to biogenic organic aerosol; however, surface observations show that organic aerosol only accounts for ~35% of PM2.5 mass and exhibits similar seasonality to total surface PM2.5. The GEOS-Chem model generally reproduces these surface aerosol measurements, but under represents the AOD seasonality observed by satellites. We show that seasonal differences in water uptake cannot sufficiently explain the magnitude of AOD increase. As CALIOP profiles indicate the presence of additional aerosol in the lower troposphere

  16. Organic matter in uranium concentration during ancient bed oxidation of carboniferons sediments

    International Nuclear Information System (INIS)

    Kruglova, V.G.; Uspenskij, V.A.; Dement'ev, P.K.; Kochenov, A.V.

    1984-01-01

    Changes in the organic matter accompanying the process of epigenetic ore formation are studied using the example of a deposit localized in carboniferous molasse strata of the Cretaceous period. Peculiarities of the organic matter as the main mineralization agent are studied by a complex of physical and themical methods. A distinct relationship between the uranium concentration and the degree of organic matter oxigenation is a most characteristic feature of the ore localization, however, there is no direct correlation between the contents of uranium and organic matter in ores. Uranium minerallzation was accumulated during infiltration of acid uraniferous.waters into grey stratum in the process of the bed oxidation zone formation oxidizing. Brown coal matter possessing a maximum adsorbability, as compared to other sedimentary rocks, apprared to be the uranium precipitator. The adsorption was accompanie by the formation of proper uranium minerals (coffinite, pitchblende) due to uranium reduction by oxidizing organic matter. Thus, the oxidative epigenesis was an are-forming process with the uranium concentration on organic matter proportionally to oxidation of the latter

  17. Gray, White Matter Concentration Changes and Their Correlation with Heterotopic Neurons in Temporal Lobe Epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Tae, Woo Suk; Joo, Eun Yun; Kim, Sung Tae; Hong, Seung Bong [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2010-02-15

    To identify changes in gray and white matter concentrations (GMC, WMC), and their relation to heterotopic neuron numbers in mesial temporal lobe epilepsy (mTLE). The gray matter or white matter concentrations of 16 left and 15 right mTLE patients who achieved an excellent surgical outcome were compared with those of 24 healthy volunteers for the left group and with 23 healthy volunteers for the right group, by optimized voxel-based morphometry using unmodulated and modulated images. A histologic count of heterotopic neurons was obtained in the white matter of the anterior temporal lobe originating from the patients' surgical specimens. In addition, the number of heterotopic neurons were tested to determine if there was a correlation with the GMC or WMC. The GMCs of the left and right mTLE groups were reduced in the ipsilateral hippocampi, bilateral thalami, precentral gyri, and in the cerebellum. The WMCs were reduced in the ipsilateral white matter of the anterior temporal lobe, bilateral parahippocampal gyri, and internal capsules, but increased in the pons and bilateral precentral gyri. The heterotopic neuron counts in the left mTLE group showed a positive correlation (r = 0.819, p < 0.0001) with GMCs and a negative correlation (r = - 0.839, p < 0.0001) with WMCs in the white matter of the anterior temporal lobe. The present study shows the abnormalities of the cortico-thalamo- hippocampal network including a gray matter volume reduction in the anterior frontal lobes and an abnormality of brain tissue concentration in the pontine area. Furthermore, heterotopic neuron numbers were significantly correlated with GMC or WMC in the left white matter of anterior temporal lobe.

  18. Optimal voxel size for measuring global gray and white matter proton metabolite concentrations using chemical shift imaging

    DEFF Research Database (Denmark)

    Hanson, Lars Peter Grüner; Adalsteinsson, E; Pfefferbaum, A

    2000-01-01

    Quantification of gray and white matter levels of spectroscopically visible metabolites can provide important insights into brain development and pathological conditions. Chemical shift imaging offers a gain in efficiency for estimation of global gray and white matter metabolite concentrations co...

  19. Concentration of elements in suspended matter discharges to Lerma River, Mexico

    International Nuclear Information System (INIS)

    Avila-Perez, P.; Tejeda, S.; Carapia, L.; Barcelo-Quintal, I.; Martinez, T.

    2011-01-01

    The S, K, Ca, Ti, V, Cr, Mn, Fe, Cu, Zn and Pb concentration and the elemental composition of particles in suspended matter from principal discharges to Lerma River, have been evaluated. The elemental concentration in suspended matter has been obtained by Energy Dispersive X-Ray Fluorescence Spectrometry. The elemental composition of particles has been obtained by means of Energy Dispersive X-Ray Spectrometry (EDS). The results show that K, Ca, Ti, Mn and Fe are mainly from natural origin in the Upper Course of the Lerma River (UCLR), where the principal contributions probably come from dragging of soils and sediments in the rainy season and Cr, Cu, Zn and Pb are mainly from anthropogenic origin where the principal contributions come from urban and industrial untreated discharge. The application of Energy Dispersive X-Ray Spectrometry plus Scanning Electron Microscopy is useful in the characterization of suspended matter in natural, anthropogenic and mixed water discharges. (author)

  20. Preservation of peptide moieties in three Spanish sulfur-rich Tertiary kerogens

    Energy Technology Data Exchange (ETDEWEB)

    Rio, J.C. del [Consejo Superior de Investigaciones Cientificas, Seville (Spain). Inst. de Recursos Naturales y Agrobiologia; Olivella, M.A.; Heras, F.X.D. de las [Escola Universitaria Politecnica de Manresa, Catalonia (Spain); Knicker, H. [Technische Universitaet Muenchen (Germany). Lehrstuhl fuer Bodenkunde

    2004-09-01

    Thermochemolysis with tetramethylammonium hydroxide (TMAH) and solid-state {sup 15}N NMR were utilized for the characterization of refractory organic nitrogen in Tertiary Spanish kerogens. The samples included sulfur-rich oil shales from the Ribesalbes (Serravallian), Libros (Tortonian) and Cerdanya (Tortonian) basins. Analysis using solid state {sup 15}N NMR showed that part of the refractory nitrogen in the kerogens corresponds to amide groups. Moreover, the release of amino acid derivatives after pyrolysis in the presence of TMAH indicated that this amide-N arose from peptide moieties. The amino acids released from the kerogens were dominated by high amounts of glycine and alanine. Minor amounts of aspartic acid, serine, {alpha}-aminobutyric acid and other unidentified amino acids were also detected. Because proteinaceous structures, including small peptides, are generally considered as being highly sensitive to diagenetic degradation, encapsulation of labile peptide material into aliphatic structures in S-rich kerogens (probably via lipid sulfurization) has been proposed to explain the survival of these moieties. Substantial amounts of fatty acids (as methyl esters) were also released from all the kerogens after pyrolysis/TMAH, indicating their highly aliphatic character. The production of both fatty acids and amino acids from the kerogens supports the encapsulation process. (author)

  1. Characterization of kerogen from Messel shale based on multistage alkaline permanganate degradation

    Energy Technology Data Exchange (ETDEWEB)

    Vitorovic, D.; Ambles, A.; Bajc, S.; Cvetkovic, O.

    1988-07-01

    A 17-step alkaline permanganate degradation of kerogen from Messel shale (F.R.G.) was carried out. A very high total yield of oxidation products was obtained (91.7% based on original kerogen). Detailed g.c.-m.s. analyses of ether-soluble acids, soluble products of further controlled permanganate degradation of precipitated acids and acids from aqueous solutions, served as a basis for the quantitative estimation of the participation of various types of products and for comparison with other kerogens. Taking into account the slight aliphatic nature of the acidic oxidation products (53.4%), the existence of an aliphatic cross-linked nucleus in the Messel shale kerogen is postulated. However, on the basis of high participation of both aromatic (21.2%), and alkane-polycarboxylic (20.2%) and cyloalkanoic (5.2%) acids, a high proportion of alicyclic, heterocyclic and aromatic structural elements in the structure of this kerogen was demonstrated. The most interesting finding was the isolation and identification, in significant amounts, of a series of monocarboxylic mono- and bicyclic cycloalkanoic acids. A small quantity of isoprenoid acids was found in the oxidation products. A homogeneous structure of the Messel shale kerogen is suggested. 17 refs., 9 figs., 4 tabs.

  2. Lyophilization and Reconstitution of Reverse-Osmosis Concentrated Natural Organic Matter from a Drinking Water Source

    Science.gov (United States)

    Disinfection by-product (DBP) research can be complicated by difficulties in shipping large water quantities and changing natural organic matter (NOM) characteristics over time. To overcome these issues, it is advantageous to have a reliable method for concentrating NOM with min...

  3. Modelling anaerobic digestion of concentrated black water and faecal matter in accumulation system

    NARCIS (Netherlands)

    Elmitwalli, T.; Zeeman, G.; Otterpohl, R.

    2011-01-01

    A dynamic mathematical model based on anaerobic digestion model no. 1 (ADM1) was developed for accumulation (AC) system treating concentrated black water and faecal matter at different temperatures. The AC system was investigated for the treatment of waste(water) produced from the following systems:

  4. Evaluation of hyperspectral reflectance for estimating dry matter and sugar concentration in processing potatoes

    Science.gov (United States)

    The measurement of sugar concentration and dry matter in processing potatoes is a time and resource intensive activity, cannot be performed in the field, and does not easily measure within tuber variation. A proposed method to improve the phenotyping of processing potatoes is to employ hyperspectral...

  5. Dry Matter Production and Leaf Elemental Concentrations of Rambutan Grown on an Acid Ultisol

    Science.gov (United States)

    Little is known about the adaptability of rambutan (Nephelium lappaceum) to highly acidic soils rich in aluminum (Al). A 2-yr field study was conducted to determine the effects of various levels of soil Al on dry matter production, plant growth, and nutrient concentration in the leaves of four cult...

  6. Release of organic nitrogen compounds from Kerogen via catalytic hydropyrolysis

    Directory of Open Access Journals (Sweden)

    Bennett B

    2000-12-01

    Full Text Available High hydrogen pressure pyrolysis (hydropyrolysis was performed on samples of solvent extracted Kimmeridge Clay Formation source rock with a maturity equivalent to ca. 0.35% vitrinite reflectance. We describe the types and distributions of organic nitrogen compounds in the pyrolysis products (hydropyrolysates using GC-MS. Compounds identified included alkyl-substituted indoles, carbazoles, benzocarbazoles, quinolines and benzoquinolines. The distributions of the isomers of methylcarbazoles, C2-alkylcarbazoles and benzocarbazoles in the hydropyrolysates were compared to a typical North Sea oil. The hydropyrolysates compared to the North Sea oil, showed increased contributions from alkylcarbazole isomers where the nitrogen group is "exposed" (no alkyl substituents adjacent to the nitrogen functionality and appreciable levels of benzo[b]carbazole relative to benzo[a]- and benzo[c]carbazoles. Hydropyrolysis is found to be an ideal technique for liberating appreciable quantities of heterocyclic organic nitrogen compounds from geomacromolecules. The products released from the immature Kimmeridge Clay are thought to represent a potential source of nitrogen compounds in the bound phase (kerogen able to contribute to the free bitumen phase during catagenesis.

  7. Analysis of Particulate matter (PM 10 and PM 2.5 concentration in Khorramabad city

    Directory of Open Access Journals (Sweden)

    Seyed Hamed Mirhosseini

    2013-01-01

    Full Text Available Aims: In this study, the concentration of PM10 and PM2.5 in eight station of Khorramabad city was analyzed. Materials and Methods: For this study, the data were taken from April 2010 to March 2011. The eight sampling point were chosen in account to Khorramabad maps. During this period, 240 daily PM samples including coarse particle (PM 10 and fine particle (PM 2.5 were collected. A two-part sampler was used to collect samples of PM. According to one-way ANOVA, multiple comparisons Scheffe, the obtained data were analyzed and then compared with the Environment protection organization standard rates. Khorramabad Results: The results revealed that during measuring the maximum concentration of PM 10 and PM 2.5 was respectively 120.9 and 101.09 μ/m 3 at Shamshirabad station. There was a significant difference between the mean values of PM 10 concentration (μg/m 3 in the seasons of summer. In addition, the mean concentrations of PM 10 in warmer months exceeded to the maximum permissible concentration. Conclusions: Year comparison of PM 10 and PM 2.5 concentration with standard were revealed particle matter concentration in summer season was higher than standard. Although total mean of particle matter was less than standard concentration.

  8. PARTICULATE MATTER CONCENTRATION AND EMISSION FACTOR IN THREE DIFFERENT LAYING HEN HOUSING SYSTEMS

    Directory of Open Access Journals (Sweden)

    Annamaria Costa

    2009-09-01

    Full Text Available The aim of this study was to evaluate PM10 concentration in three different laying hens houses (traditional battery cages with aerated open manure storage, aviary system and vertical tiered cages with manure belts with forced air drying and to evaluate particulate matter emission into atmosphere during one year of observation. Internal and external temperature and relative humidity, ventilation rate, PM10 concentration have been continuously monitored in order to evaluate particulate matter concentration changes during the day and the season and to define PM10 emission factors. PM10 concentration was corrected by gravimetric technique to lower measurements error. In the aviary system house, TSP and fine particulate matter (particles smaller than 2.5 micron concentration was measured. Average yearly PM10 concentration was remarkably higher in the aviary system house with 0.215 mg m-3 vs 108 mg m-3 for the ventilated belt house and vs 0.094 mg m-3 for the traditional battery cages house. In the Aviary system housing, TSP concentration was 0.444 mg m-3 and PM2.5 was 0.032 mg m-3, highlighting the existence of a severe working environment for men and animals. Recorded values for PM10 emission were 0.433 mg h-1 hen-1 for battery cages housing type, 0.081 mg h-1 hen-1 for ventilated belt cages house, values lower than those available in literature, while the aviary system housing type showed the highest PM10 emission (1.230 mg h-1 hen-1 with appreciable peaks during the morning, together with the increased animal activity and daily farmer operations, as feed administration, cleaning and droppings removal.

  9. pH dependence of steroid hormone-organic matter interactions at environmental concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Neale, Peta A. [School of Engineering and Electronics, University of Edinburgh, Edinburgh, EH9 3JL (United Kingdom)], E-mail: p.neale@ed.ac.uk; Escher, Beate I. [Swiss Federal Institute of Aquatic Science and Technology (Eawag), 8600, Duebendorf (Switzerland); Schaefer, Andrea I. [School of Engineering and Electronics, University of Edinburgh, Edinburgh, EH9 3JL (United Kingdom)

    2009-01-15

    The interaction of estradiol, estrone, progesterone and testosterone with environmentally relevant concentrations of Aldrich humic acid, alginic acid and tannic acid was studied using solid-phase microextraction (SPME). Since bulk organic matter and certain hormones such as estradiol and estrone contain dissociable functional groups, the effect of pH on sorption was investigated as this will influence their fate and bioavailability. For humic acid and tannic acid, sorption was strongest at acidic pH when the bulk organic matter was in a non-dissociated form and decreased when they became partially negatively charged. At acidic and neutral pH the strength of partitioning was influenced by hormone functional groups content, with the strongest sorption observed for progesterone and estrone. At alkaline pH conditions, when the bulk organics were dissociated, sorption decreased considerably (up to a factor of 14), although the non-dissociated hormones testosterone and progesterone indicated greater sorption to humic acid at pH 10 compared to the partially deprotonated estradiol and estrone. This study demonstrates that SPME can be used to assess organic matter sorption behaviour of a selected range of micropollutants and at environmentally relevant organic matter concentrations.

  10. Intracerebral haemorrhage associated with hourly concentration of ambient particulate matter: case-crossover analysis.

    Science.gov (United States)

    Yamazaki, S; Nitta, H; Ono, M; Green, J; Fukuhara, S

    2007-01-01

    To examine the association of hourly time lagged concentration of ambient particulate matter and death due to stroke. Mortality data for five years (January 1990 to December 1994) were obtained from the Ministry of Health, Labour, and Welfare of Japan. Data were used only if the deceased was 65 years old or older at the time of death, if death was attributed to intracerebral haemorrhage or ischaemic stroke, and if the deceased lived in one of 13 major urban areas. Hourly mean concentrations of PM7, NO2, and photochemical oxidants were measured at monitoring stations in the 13 areas. Time stratified case-crossover analysis was used to examine the data for evidence of triggering stroke mortality. The 1-hour mean concentration of PM7 measured about 2 hours before death was associated with the risk of death due to intracerebral haemorrhage from April to September (odds ratio = 2.40, 95% CI 1.48 to 3.89, for exposure to PM7 of more than 200 microg/m3 (threshold)). The higher risk was independent of the 24-hour mean concentration of PM7. PM7 was not associated with death due to ischaemic stroke. Transiently high concentrations of PM7 are associated with death due to intracerebral haemorrhage. Air quality standards or guidelines for particulate matter should be based not only on 24-hour mean concentrations, but also on hourly data.

  11. Intracerebral haemorrhage associated with hourly concentration of ambient particulate matter: case‐crossover analysis

    Science.gov (United States)

    Yamazaki, S; Nitta, H; Ono, M; Green, J; Fukuhara, S

    2007-01-01

    Aims To examine the association of hourly time lagged concentration of ambient particulate matter and death due to stroke. Methods Mortality data for five years (January 1990 to December 1994) were obtained from the Ministry of Health, Labour, and Welfare of Japan. Data were used only if the deceased was 65 years old or older at the time of death, if death was attributed to intracerebral haemorrhage or ischaemic stroke, and if the deceased lived in one of 13 major urban areas. Hourly mean concentrations of PM7, NO2, and photochemical oxidants were measured at monitoring stations in the 13 areas. Time stratified case‐crossover analysis was used to examine the data for evidence of triggering stroke mortality. Results The 1‐hour mean concentration of PM7 measured about 2 hours before death was associated with the risk of death due to intracerebral haemorrhage from April to September (odds ratio = 2.40, 95% CI 1.48 to 3.89, for exposure to PM7 of more than 200 μg/m3 (threshold)). The higher risk was independent of the 24‐hour mean concentration of PM7. PM7 was not associated with death due to ischaemic stroke. Conclusions Transiently high concentrations of PM7 are associated with death due to intracerebral haemorrhage. Air quality standards or guidelines for particulate matter should be based not only on 24‐hour mean concentrations, but also on hourly data. PMID:16847037

  12. PAHs concentration and toxicity in organic solvent extracts of atmospheric particulate matter and sea sediments.

    Science.gov (United States)

    Ozaki, Noriatsu; Takeuchi, Shin-ya; Kojima, Keisuke; Kindaichi, Tomonori; Komatsu, Toshiko; Fukushima, Takehiko

    2012-01-01

    The concentration of polycyclic aromatic hydrocarbons (PAHs) and the toxicity to marine bacteria (Vibrio fischeri) were measured for the organic solvent extracts of sea sediments collected from an urban watershed area (Hiroshima Bay) of Japan and compared with the concentrations and toxicity of atmospheric particulate matter (PM). In atmospheric PM, the PAHs concentration was highest in fine particulate matter (FPM) collected during cold seasons. The concentrations of sea sediments were 0.01-0.001 times those of atmospheric PM. 1/EC50 was 1-10 L g(-1) PM for atmospheric PM and 0.1-1 L g(-1) dry solids for sea sediments. These results imply that toxic substances from atmospheric PM are diluted several tens or hundreds of times in sea sediments. The ratio of the 1/EC50 to PAHs concentration ((1/EC50)/16PAHs) was stable for all sea sediments (0.1-1 L μg(-1) 16PAHs) and was the same order of magnitude as that of FPM and coarse particulate matter (CPM). The ratio of sediments collected from the west was more similar to that of CPM while that from the east was more similar to FPM, possibly because of hydraulic differences among water bodies. The PAHs concentration pattern analyses (principal component analysis and isomer ratio analysis) were conducted and the results showed that the PAHs pattern in sea sediments was quite different to that of FPM and CPM. Comparison with previously conducted PAHs analyses suggested that biomass burning residues comprised a major portion of these other sources.

  13. Particulate Matter Mass Concentration in Residential Prefabricated Buildings Related to Temperature and Moisture

    Science.gov (United States)

    Kraus, Michal; Juhásová Šenitková, Ingrid

    2017-10-01

    Building environmental audit and the assessment of indoor air quality (IAQ) in typical residential buildings is necessary process to ensure users’ health and well-being. The paper deals with the concentrations on indoor dust particles (PM10) in the context of hygrothermal microclimate in indoor environment. The indoor temperature, relative humidity and air movement are basic significant factors determining the PM10 concentration [μg/m3]. The experimental measurements in this contribution represent the impact of indoor physical parameters on the concentration of particulate matter mass concentration. The occurrence of dust particles is typical for the almost two-thirds of interiors of the buildings. Other parameters indoor environment, such as air change rate, volume of the room, roughness and porosity of the building material surfaces, static electricity, light ions and others, were set constant and they are not taken into account in this study. The mass concentration of PM10 is measured during summer season in apartment of residential prefabricated building. The values of global temperature [°C] and relative humidity of indoor air [%] are also monitored. The quantity of particulate mass matter is determined gravimetrically by weighing according to CSN EN 12 341 (2014). The obtained results show that the temperature difference of the internal environment does not have a significant effect on the concentration PM10. Vice versa, the difference of relative humidity exhibits a difference of the concentration of dust particles. Higher levels of indoor particulates are observed for low values of relative humidity. The decreasing of relative air humidity about 10% caused 10µg/m3 of PM10 concentration increasing. The hygienic limit value of PM10 concentration is not exceeded at any point of experimental measurement.

  14. Sorption of phenanthrene and benzene on differently structural kerogen: important role of micropore-filling.

    Science.gov (United States)

    Zhang, Yulong; Ma, Xiaoxuan; Ran, Yong

    2014-02-01

    Shale was thermally treated to obtain a series of kerogen with varied maturation. Their chemical, structural and porous properties were related to the sorption and/or desorption behaviors of phenanthrene and benzene. As the treatment temperature increases, aliphatic and carbonyl carbon of the kerogen samples decrease, while their aromaticity and maturation increase. Meanwhile, the isothermal nonlinearity of phenanthrene and benzene increases whereas the sorption capacity and micropore adsorption volumes (Vo,d) initially increase and then decrease. The Vo,d of benzene is significantly correlated with, but higher than that of phenanthrene, suggesting similar micropore filling mechanism and molecular sieve effect. The benzene desorption exhibits hysteresis, which is related to the pore deformation of the kerogen and the entrapment of solute in the kerogen matrix. The Vo,d of phenanthrene and benzene on the kerogen samples accounts for 23-46% and 36-65% of the maximum sorption volumes, respectively, displaying the importance of the micropore filling. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Kerogen-mineral reactions at raised temperatures in the presence of water

    Energy Technology Data Exchange (ETDEWEB)

    Eglinton, T I; Rowland, S J; Curtis, C D; Douglas, A G

    1986-01-01

    Kerogen has been artificially matured under hydrous pyrolysis conditions in the presence of various minerals in order to investigate the influence of the latter on the organic products. In addition to three clay minerals (montmorillonite, illite, kaolinite), calcium carbonate and limonite were also employed as inorganic substrates. Kerogen (Type II) isolated from the Kimmeridge Blackstone band was heated in the presence of water and a 20-fold excess of mineral phase at two different temperatures (280 and 330/sup 0/C) for 72 hr. Control experiments were also carried out using kerogen and water only and kerogen under anhydrous conditions. This preliminary study describes the bulk composition of the pyrolysates with detailed analyses of the aliphatic hydrocarbon distributions being provided by gas chromatography and combined gas chromatography-mass spectrometry. In the 280/sup 0/C experiments, considerably more organic-soluble pyrolysate (15% by weight of original kerogen) was produced when calcium carbonate was the inorganic phase. At 330/sup 0/C, all samples generated much greater amounts of organic-soluble products with calcium carbonate again producing a large yield (approx. 40% wt/wt). Biomarker epimerization reactions have also proceeded further in the 330/sup 0/C pyrolysate formed in the presence of calcium carbonate than with other inorganic phases. Implications of these and other observations are discussed.

  16. Assessment of relative accuracy in the determination of organic matter concentrations in aquatic systems

    Science.gov (United States)

    Aiken, G.; Kaplan, L.A.; Weishaar, J.

    2002-01-01

    Accurate determinations of total (TOC), dissolved (DOC) and particulate (POC) organic carbon concentrations are critical for understanding the geochemical, environmental, and ecological roles of aquatic organic matter. Of particular significance for the drinking water industry, TOC measurements are the basis for compliance with US EPA regulations. The results of an interlaboratory comparison designed to identify problems associated with the determination of organic matter concentrations in drinking water supplies are presented. The study involved 31 laboratories and a variety of commercially available analytical instruments. All participating laboratories performed well on samples of potassium hydrogen phthalate (KHP), a compound commonly used as a standard in carbon analysis. However, problems associated with the oxidation of difficult to oxidize compounds, such as dodecylbenzene sulfonic acid and caffeine, were noted. Humic substances posed fewer problems for analysts. Particulate organic matter (POM) in the form of polystyrene beads, freeze-dried bacteria and pulverized leaf material were the most difficult for all analysts, with a wide range of performances reported. The POM results indicate that the methods surveyed in this study are inappropriate for the accurate determination of POC and TOC concentration. Finally, several analysts had difficulty in efficiently separating inorganic carbon from KHP solutions, thereby biasing DOC results.

  17. Pre-treatment and ethanol fermentation potential of olive pulp at different dry matter concentrations

    DEFF Research Database (Denmark)

    Haagensen, Frank Drøscher; Skiadas, Ioannis V.; Gavala, Hariklia N.

    2009-01-01

    potential of the olive pulp, which is the semi solid residue generated from the two-phase processing of the olives for olive oil production. Wet oxidation and enzymatic hydrolysis have been applied aiming at the enhancement of carbohydrates' bioavailability. Different concentrations of enzymes and enzymatic......, implying that wet oxidation is not a recommended pre-treatment process for olive pulp at the conditions tested. It was also showed that increased dry matter concentration did not have a negative effect on the release of sugars, indicating that the cellulose and xylan content of the olive pulp is relatively...

  18. Satellite-based retrieval of particulate matter concentrations over the United Arab Emirates (UAE)

    Science.gov (United States)

    Zhao, Jun; Temimi, Marouane; Hareb, Fahad; Eibedingil, Iyasu

    2016-04-01

    In this study, an empirical algorithm was established to retrieve particulate matter (PM) concentrations (PM2.5 and PM10) using satellite-derived aerosol optical depth (AOD) over the United Arab Emirates (UAE). Validation of the proposed algorithm using ground truth data demonstrates its good accuracy. Time series of in situ measured PM concentrations between 2014 and 2015 showed high values in summer and low values in winter. Estimated and in situ measured PM concentrations were higher in 2015 than 2014. Remote sensing is an essential tool to reveal and back track the seasonality and inter-annual variations of PM concentrations and provide valuable information on the protection of human health and the response of air quality to anthropogenic activities and climate change.

  19. Composition, peat-forming vegetation and kerogen paraffinicity of Cenozoic coals: Relationship to variations in the petroleum generation potential (Hydrogen Index)

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, H.I.; Lindstroem, S.; Nytoft, H.P.; Rosenberg, P. [Geological Survey of Denmark and Greenland (GEUS), Oester Voldgade 10, DK-1350 Copenhagen (Denmark)

    2009-04-01

    Coals with similar thermal maturity and from the same deposit normally show a considerable range in petroleum generation potential as measured by the Hydrogen Index (HI). This variation may partly be related to variations in plant input to the precursor mires and organic matter preservation. It is widely accepted that some Cenozoic coals and coaly sediments have the potential to generate oil, which is related to the coal's paraffinicity. Coal paraffinicity is not readily reflected in the bulk HI. In this paper, the relationships between measured HI and coal composition, coal kerogen paraffinicity and floral input have been investigated in detail for three sets of coals from Colombia/Venezuela, Indonesia, and Vietnam. The samples in each coal set are largely of iso-rank. The petroleum generation potential was determined by Rock-Eval pyrolysis. Reflected light microscopy was used to analyse the organic matter (maceral) composition and the thermal maturity was determined by vitrinite reflectance (VR) measurements. The botanical affinity of pollen and spores was analysed by palynology. Coal kerogen paraffinicity was determined by ruthenium tetroxide-catalysed oxidation (RTCO) followed by chain length analysis and quantification (mg/g TOC) of the liberated aliphatic chains. The coals are dominated by huminite, in particular detrohuminite. Only the Vietnamese coals are rich in microscopically visible liptinite. The pollen and spores suggest that the coals were derived principally from complex angiosperm mire vegetations, with subordinate proportions of ferns that generally grew in a subtropical to tropical climate. Measured HI values vary considerably, but for the majority of the coals the values lie between approximately 200 mg HC/g TOC and 300 mg HC/g TOC. Aliphatics yielding monocarboxylic acids dominate in the coal kerogen, whereas aliphatics yielding dicarboxylic acids are secondary. However, the dicarboxylic acids show that cross-linking long-chain aliphatics

  20. Attachment of di- and tricarboxylic acids to the starting structure of kukersite kerogen

    Energy Technology Data Exchange (ETDEWEB)

    Pobul, L; Mannik, A

    1974-01-01

    Oxidation of the kerogen of kukersite by alkaline permanganate at 50/sup 0/C gave a product containing straight-chain dicarboxylic acids (up to 80%), among which C/sub 4/-C/sub 10/ acids predominated (over 70%). Tricarboxylic acids (15 to 20%) and ..cap alpha..-methyl dicarboxylic acids (4 to 10%) were present. Straight-chain monocarboxylic acids, their isomers, and phenyl derivatives contributed less than 1%. Probably, ..cap alpha..-methyl dicarboxylic and tricarboxylic acids were original structural units of the kerogen. Similar oxidations of Baltic shale indicated that kerogens of different combustible shales differ in chemical composition, but the content of polymers of fatty acids was characteristic. Oxidation of the polymeric acids gave straight-chain mono- and dicarboxylic acids.

  1. Results of measurements of particulate matter concentrations inside a pig fattening facility

    Directory of Open Access Journals (Sweden)

    Ulens, T.

    2016-01-01

    Full Text Available Description of the subject. This research note discusses the results of measurements of particulate matter concentrations inside a pig fattening facility. Objectives. The objectives of the present study were to investigate the correlations between the different size fractions of indoor particulate matter (PM inside a pig fattening facility and to investigate the evolution of particle size distribution (PSD through a fattening period and between two housing systems and two cleaning protocols. Method. Data from two consecutive fattening periods in a commercial pig barn were used. Results. Very high correlations were found between PM10 and PM2.5 indoor concentrations. Depending on the measuring instrument, high or low correlations were found between PM1 and PM10 or PM2.5 indoor concentrations. No differences in PSD could be found between the two housing systems or the two cleaning protocols. Conclusions. The results from the present study showed high correlations between the indoor concentrations of PM10 and PM2.5. In the present study, no differences in PSD were found.

  2. Seasonal Variability of Airborne Particulate Matter and Bacterial Concentrations in Colorado Homes

    Directory of Open Access Journals (Sweden)

    Nicholas Clements

    2018-04-01

    Full Text Available Aerosol measurements were collected at fifteen homes over the course of one year in Colorado (USA to understand the temporal variability of indoor air particulate matter and bacterial concentrations and their relationship with home characteristics, inhabitant activities, and outdoor air particulate matter (PM. Indoor and outdoor PM2.5 concentrations averaged (±st. dev. 8.1 ± 8.1 μg/m3 and 6.8 ± 4.5 μg/m3, respectively. Indoor PM2.5 was statistically significantly higher during summer compared to spring and winter; outdoor PM2.5 was significantly higher for summer compared to spring and fall. The PM2.5 I/O ratio was 1.6 ± 2.4 averaged across all homes and seasons and was not statistically significantly different across the seasons. Average indoor PM10 was 15.4 ± 18.3 μg/m3 and was significantly higher during summer compared to all other seasons. Total suspended particulate bacterial biomass, as determined by qPCR, revealed very little seasonal differences across and within the homes. The qPCR I/O ratio was statistically different across seasons, with the highest I/O ratio in the spring and lowest in the summer. Using one-minute indoor PM10 data and activity logs, it was observed that elevated particulate concentrations commonly occurred when inhabitants were cooking and during periods with elevated outdoor concentrations.

  3. Early gray-matter and white-matter concentration in infancy predict later language skills: a whole brain voxel-based morphometry study.

    Science.gov (United States)

    Deniz Can, Dilara; Richards, Todd; Kuhl, Patricia K

    2013-01-01

    Magnetic resonance imaging (MRI) brain scans were obtained from 19 infants at 7 months. Expressive and receptive language performance was assessed at 12 months. Voxel-based morphometry (VBM) identified brain regions where gray-matter and white-matter concentrations at 7 months correlated significantly with children's language scores at 12 months. Early gray-matter concentration in the right cerebellum, early white-matter concentration in the right cerebellum, and early white-matter concentration in the left posterior limb of the internal capsule (PLIC)/cerebral peduncle were positively and strongly associated with infants' receptive language ability at 12 months. Early gray-matter concentration in the right hippocampus was positively and strongly correlated with infants' expressive language ability at 12 months. Our results suggest that the cerebellum, PLIC/cerebral peduncle, and the hippocampus may be associated with early language development. Potential links between these structural predictors and infants' linguistic functions are discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Characterisation of Tertiary Catalan lacustrine oil shales: Discovery of extremely organic sulphur-rich type I kerogens

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Las Heras, F.X.C. de; Bergen, P.F. van; Leeuw, J.W. de

    1993-01-01

    The kerogens of three Tertiary Catalan lacustrine oil shales were analyzed by light microscopy, flash pyrolysis-gas chromatography-mass spectrometry, and bulk composition methods (elemental analysis, Rock Eval pyrolysis). Two of the three kerogens (Ribesalbes and Campins) are extremely rich in

  5. Nitrogen concentration in dry matter of the fifth leaf during growth of greenhouse tomato plants

    Directory of Open Access Journals (Sweden)

    Rattin Jorge E.

    2002-01-01

    Full Text Available The nitrogen concentration in dry matter of the fifth leaf during growth of a greenhouse tomato crop was determined. Plants of hybrid Monte Carlo were grown in 4.5 L bags, using a commercial substrate, in a plant density of 3.3 plants m-2. A nutrient solution containing, in mmol L-1: KNO3, 4.0; K2SO4, 0.9; Ca(NO32, 3.75; KH2PO4, 1.5; MgSO4, 1.0; iron chelate 19. 10³, was used as reference. Microelements were added by a commercial mixture. The T3 treatment was equal to the reference nutrient solution, whereas in treatments T1, T2, T4 and T5 quantities of all nutrients from T3 were multiplied by 0.25, 0.50, 1.25 and 1.50, respectively. In each treatment, the volume of 1 L of nutrient solution was supplied to each plant once a week by fertigation. Periodically destructive measurements were made from anthesis to ripening of the first truss, to determine dry matter and N concentration in shoot and in fifth leaf tissues, counted from the apex to the bottom of the plant. Five dilution curves were fitted from data of N concentration in the fifth leaf and shoot dry matter accumulation during growth of plants. A general relationship was adjusted between actual N concentration in shoot (Nt and in the fifth leaf (Nf: Nt = 1.287 Nf (R² = 0.80. This relationship could be used to estimate the N status of plants by means of a nitrogen nutrition index (NNI, from analysis of the fifth leaf sap.

  6. Melanoidins-kerogen precursors and geochemical lipid sinks: a study using pyrolysis gas chromatography (PGC)

    Energy Technology Data Exchange (ETDEWEB)

    Larter, S R; Douglas, A G

    1980-12-01

    Melanoidins, acidic polymeric products of amino acid/sugar condensation reactions, are shown to be capable of reacting with and binding functionalized lipid molecules. Pyrolysis gas chromatography is used to monitor the inclusion of lipids (alcohols and acids) into, and to monitor the changes in composition caused by artificial diagenesis of, the melanoidins. Artificial diagenesis of the lipid-containing melanoidins produces a material resembling kerogen. The possible role of melanoidins in the formation of krogen is discussed as are internal transformations within kerogens during diagenesis.

  7. Seasonal Variability of Concentration and Air Quality of Ambient Particulate Matter in Sosnowiec City

    Directory of Open Access Journals (Sweden)

    Jolanta Cembrzyńska

    2015-12-01

    Full Text Available Introduction: Exposing the population to more than standard concentration of particulate matter (PM is a crucial factor shaping the public health on urbanized areas both in Europe and Poland. In most cases, exceeded air quality standards relate to the winter period, in which there has been the greatest amount. Many studies have indicated, that exposure to PM can cause adverse health effects. Human exposure especially to fine particles (with an aerodynamic diameter less than 2.5 µm, causes risk of cardiovascular and respiratory diseases, due to daily mortality and hospital admissions. Various types of epidemiological studies have indicated, that ambient air pollution is responsible for increasing risk of lung cancer. For this reason, in 2013 The International Agency for Research on Cancer (IARC classified outdoor air pollution and particulate matter as carcinogenic to humans (Group 1.

  8. The kinetics of sterane biological marker release and degradation processes during the hydrous pyrolysis of vitrinite kerogen

    Science.gov (United States)

    Abbott, G. D.; Wang, G. Y.; Eglinton, T. I.; Home, A. K.; Petch, G. S.

    1990-09-01

    The hydrous pyrolysis of a mineral-free vitrinite kerogen (Dinantian coal Lower Carboniferous, North East England) has been carried out at four temperatures (270, 300, 330, and 350°C) for heating times ranging from 2 to 648 h. No significant differences in the epimer-based maturation parameters 20S/(20S + 20R)-5α(H),14α(H),17α(H) C 29 non-rearranged steranes and 22S/(22S+22R)-17α(H), 21β(H) homohopanes were found for a comparison between "expelled oil" and "bitumen" fractions in the resulting pyrolysates. A deuterated model compound ((20R)-5α(H),14α(H),17α(H)-[2,2,4,4-d 4] cholestane) was added to a number of preextracted kerogens (vitrinite, Kimmeridge, Messel and Monterey) and the mixtures were heated under typical hydrous pyrolysis conditions. These experiments showed that direct chiral isomerisation at C-20 in the non-rearranged steranes appears to be relatively unimportant during hydrous pyrolysis which has also been suggested by other recent studies on geological samples.A kinetic model comprising consecutive release and degradation processes was derived to measure first-order rate coefficients from the bi-exponential concentration-time functions of both the (20R)-and (20S)-5α(H),14α(H),17α(H) C 29 "free" steranes in the vitrinite kerogen pyrolysates. This data was then used to calculate preliminary Arrhenius parameters for release ((20S): ΔEa = 125 ± 30 kJ mol -1, A ≈ 4.7 × 10 5 s -1;(20R): ΔEa = 151 ± 39 kJ mol -1, A ≈ 2.7 × 10 9 s -1) and degradation ((20S): ΔEa = 104 ± 22 kJ mol -1, A ≈ 5.8 × 10 3 s -1; (20R): Δa = 87 ± 6 kJ mol -1, A ≈ 2.2 × 10 2 s -1) of the above individual isomers and the values were found to be consistent with a free-radical chain mechanism. This work helps in the greater understanding of the important biomarker reactions that prevail in hydrous pyrolysis experiments.

  9. Assessment of background particulate matter concentrations in small cities and rural locations--Prince George, Canada.

    Science.gov (United States)

    Veira, Andreas; Jackson, Peter L; Ainslie, Bruce; Fudge, Dennis

    2013-07-01

    This study investigates the development and application of a simple method to calculate annual and seasonal PM2.5 and PM10 background concentrations in small cities and rural areas. The Low Pollution Sectors and Conditions (LPSC) method is based on existing measured long-term data sets and is designed for locations where particulate matter (PM) monitors are only influenced by local anthropogenic emission sources from particular wind sectors. The LPSC method combines the analysis of measured hourly meteorological data, PM concentrations, and geographical emission source distributions. PM background levels emerge from measured data for specific wind conditions, where air parcel trajectories measured at a monitoring station are assumed to have passed over geographic sectors with negligible local emissions. Seasonal and annual background levels were estimated for two monitoring stations in Prince George, Canada, and the method was also applied to four other small cities (Burns Lake, Houston, Quesnel, Smithers) in northern British Columbia. The analysis showed reasonable background concentrations for both monitoring stations in Prince George, whereas annual PM10 background concentrations at two of the other locations and PM2.5 background concentrations at one other location were implausibly high. For those locations where the LPSC method was successful, annual background levels ranged between 1.8 +/- 0.1 microg/m3 and 2.5 +/- 0.1 microg/m3 for PM2.5 and between 6.3 +/- 0.3 microg/m3 and 8.5 +/- 0.3 microg/m3 for PM10. Precipitation effects and patterns of seasonal variability in the estimated background concentrations were detectable for all locations where the method was successful. Overall the method was dependent on the configuration of local geography and sources with respect to the monitoring location, and may fail at some locations and under some conditions. Where applicable, the LPSC method can provide a fast and cost-efficient way to estimate background PM

  10. Spatial interpolation of fine particulate matter concentrations using the shortest wind-field path distance.

    Directory of Open Access Journals (Sweden)

    Longxiang Li

    Full Text Available Effective assessments of air-pollution exposure depend on the ability to accurately predict pollutant concentrations at unmonitored locations, which can be achieved through spatial interpolation. However, most interpolation approaches currently in use are based on the Euclidean distance, which cannot account for the complex nonlinear features displayed by air-pollution distributions in the wind-field. In this study, an interpolation method based on the shortest path distance is developed to characterize the impact of complex urban wind-field on the distribution of the particulate matter concentration. In this method, the wind-field is incorporated by first interpolating the observed wind-field from a meteorological-station network, then using this continuous wind-field to construct a cost surface based on Gaussian dispersion model and calculating the shortest wind-field path distances between locations, and finally replacing the Euclidean distances typically used in Inverse Distance Weighting (IDW with the shortest wind-field path distances. This proposed methodology is used to generate daily and hourly estimation surfaces for the particulate matter concentration in the urban area of Beijing in May 2013. This study demonstrates that wind-fields can be incorporated into an interpolation framework using the shortest wind-field path distance, which leads to a remarkable improvement in both the prediction accuracy and the visual reproduction of the wind-flow effect, both of which are of great importance for the assessment of the effects of pollutants on human health.

  11. Characterization of oil shale, isolated kerogen, and post-pyrolysis residues using advanced 13 solid-state nuclear magnetic resonance spectroscopy

    Science.gov (United States)

    Cao, Xiaoyan; Birdwell, Justin E.; Chappell, Mark A.; Li, Yuan; Pignatello, Joseph J.; Mao, Jingdong

    2013-01-01

    Characterization of oil shale kerogen and organic residues remaining in postpyrolysis spent shale is critical to the understanding of the oil generation process and approaches to dealing with issues related to spent shale. The chemical structure of organic matter in raw oil shale and spent shale samples was examined in this study using advanced solid-state 13C nuclear magnetic resonance (NMR) spectroscopy. Oil shale was collected from Mahogany zone outcrops in the Piceance Basin. Five samples were analyzed: (1) raw oil shale, (2) isolated kerogen, (3) oil shale extracted with chloroform, (4) oil shale retorted in an open system at 500°C to mimic surface retorting, and (5) oil shale retorted in a closed system at 360°C to simulate in-situ retorting. The NMR methods applied included quantitative direct polarization with magic-angle spinning at 13 kHz, cross polarization with total sideband suppression, dipolar dephasing, CHn selection, 13C chemical shift anisotropy filtering, and 1H-13C long-range recoupled dipolar dephasing. The NMR results showed that, relative to the raw oil shale, (1) bitumen extraction and kerogen isolation by demineralization removed some oxygen-containing and alkyl moieties; (2) unpyrolyzed samples had low aromatic condensation; (3) oil shale pyrolysis removed aliphatic moieties, leaving behind residues enriched in aromatic carbon; and (4) oil shale retorted in an open system at 500°C contained larger aromatic clusters and more protonated aromatic moieties than oil shale retorted in a closed system at 360°C, which contained more total aromatic carbon with a wide range of cluster sizes.

  12. Bacterial biofilms utilization of low concentrations of organic matter on hydrophile surfaces submerged in seawater

    Directory of Open Access Journals (Sweden)

    Aurelia Manuela Moldoveanu

    2011-12-01

    Full Text Available A series of experiments were designed to determine the effect and the metabolic rate utilization of various types of organic matter in low concentration by heterotrophic marine bacteria using as Henrici slide technique as culture method and “in vitro” static conditions in sterile containers in order to obtain bacterial biofilms on the hydrophile surface of glass. The bacteria attachment and biofilm formation was analyzed for a period from 2 hours to 72 hours in order to observe de first phase of biofilm formation in condition of seawater supplied  with organic matter and noninvasive optic microscopy analysis. The utilization of five different  types of organic substances (amino-acid mixture, yeast extract, tryptone, glucose and starch reveled that bacteria multiply and are otherwise physiologically active in this very dilute nutrient solutions of 0.1% and also the results revealed that the bacterial growth was considerable in the case of the substances like amino-acid mixture with a total density of 30.9∙103 cells/mm2  and tryptone with a total density of 28.85∙103 cells/mm2  comparable to the other types of organic matter used to supply the seawater

  13. Concentration and Size Distribution of Particulate Matter in a Broiler House Ambient Air

    Directory of Open Access Journals (Sweden)

    Ismael Rodrigues Amador

    2016-07-01

    Full Text Available Atmospheric particulate matter (PM is an important constituent of ambient air. The determination of its concentration and size distribution in different environments is essential because of its ability to penetrate deeply into animal and human respiratory tract. In this study, air sampling was performed in a broiler house to estimate the concentration and size distribution of PM emitted along with its activities. Low-vol impactor (< 10 mm, cyclones (< 2.5 e < 1.0 mm, and Sioutas cascade impactor (> 2.5; 1.0 – 2.5; 0.50 – 1.0; 0.25 – 0.50; < 0.25 mm connected with membrane pumps were used. PM10 showed high concentration (209 - 533 mg m-3. PM2.5 and PM1.0 initially showed relatively low concentration (20.8 and 16.0 mg m-3 respectively with significantly increasing levels (412.9 and 344.8 mg m-3 respectively during the samplings. It was also possible to observe the contribution of fine particles. This was evidenced by the high correlation between PM2.5 and PM1.0 and by the profile of particle distribution in the Sioutas sampler. PM concentration levels are considered excessively high, with great potential to affect animal and human health. DOI: http://dx.doi.org/10.17807/orbital.v8i3.847 

  14. Bayesian spatio-temporal modeling of particulate matter concentrations in Peninsular Malaysia

    Science.gov (United States)

    Manga, Edna; Awang, Norhashidah

    2016-06-01

    This article presents an application of a Bayesian spatio-temporal Gaussian process (GP) model on particulate matter concentrations from Peninsular Malaysia. We analyze daily PM10 concentration levels from 35 monitoring sites in June and July 2011. The spatiotemporal model set in a Bayesian hierarchical framework allows for inclusion of informative covariates, meteorological variables and spatiotemporal interactions. Posterior density estimates of the model parameters are obtained by Markov chain Monte Carlo methods. Preliminary data analysis indicate information on PM10 levels at sites classified as industrial locations could explain part of the space time variations. We include the site-type indicator in our modeling efforts. Results of the parameter estimates for the fitted GP model show significant spatio-temporal structure and positive effect of the location-type explanatory variable. We also compute some validation criteria for the out of sample sites that show the adequacy of the model for predicting PM10 at unmonitored sites.

  15. Petrographic and geochemical composition of kerogen in the Furongian (U. Cambrian) Alum Shale, central Sweden

    DEFF Research Database (Denmark)

    Sanei, H.; Petersen, H. I.; Schovsbo, N. H.

    2014-01-01

    that organic-rich Alum Shale (TOC: 8.9-28.0. wt.%) contains mainly immature, predominantly algal-derived kerogen with unusually reduced hydrocarbon generation potential as suggested by relatively low Hydrogen Index (HI) values (HI: 251-471. mg HC/g TOC) and high degree of aromaticity. In the absence of thermal...

  16. Structural and isotopic analysis of kerogens in sediments rich in free sulfurised Botryococcus braunii biomarkers

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Grice, K.; Schouten, S.; Blokker, P.; Derenne, S.; Largeau, C.; Nissenbaum, A.

    2003-01-01

    Type I kerogens of two relatively immature, unusual hypersaline sediments [with extracts rich in sulfurised Botryococcus braunii (B. braunii) biomarkers] of Miocene/Pliocene age from the Sdom Formation (Dead Sea, Israel), have been investigated using a variety of organic geochemical techniques. Py

  17. Particulate Matter and Black Carbon Concentration Levels in Ashaiman, a Semi-Urban Area of Ghana, 2008

    OpenAIRE

    Sam-Quarcoo Dotse; Joshua Kwame Asane; F.G. Ofosu

    2012-01-01

    Particulate matter and black carbon concentration levels in Ashaiman, a semi-urban area of Ghana was assessed. Using IVL PM2.5 and PM10 particle samplers, airborne particulate matter was sampled on Teflon filters for a period of three months. In addition to determination of particulate mass in the two fractions by gravimetrical method, aerosol filters were analyzed to determine Black Carbon (BC) concentration levels using the black smoke method. BC fractions in fine and coarse, together with ...

  18. Artificial neural network forecast application for fine particulate matter concentration using meteorological data

    Directory of Open Access Journals (Sweden)

    M. Memarianfard

    2017-09-01

    Full Text Available Most parts of the urban areas are faced with the problem of floating fine particulate matter. Therefore, it is crucial to estimate the amounts of fine particulate matter concentrations through the urban atmosphere. In this research, an artificial neural network technique was utilized to model the PM2.5 dispersion in Tehran City. Factors which are influencing the predicted value consist of weather-related and air pollution-related data, i.e. wind speed, humidity, temperature, SO2, CO, NO2, and PM2.5 as target values. These factors have been considered in 19 measuring stations (zones over urban area across Tehran City during four years, from March 2011 to March 2015. The results indicate that the network with hidden layer including six neurons at training epoch 113, has the best performance with the lowest error value (MSE=0.049438 on considering PM2.5 concentrations across metropolitan areas in Tehran. Furthermore, the “R” value for regression analysis of training, validation, test, and all data are 0.65898, 0.6419, 0.54027, and 0.62331, respectively. This study also represents the artificial neural networks have satisfactory implemented for resolving complex patterns in the field of air pollution.

  19. Impact of regional ventilation changes on surface particulate matter concentrations in South Korea

    Science.gov (United States)

    Kim, H. C.; Stein, A. F.; Chai, T.; Ngan, F.; Kim, B. U.; Jin, C. S.; Hong, S. Y.; Park, R.; Son, S. W.; Bae, C.; Bae, M.; Song, C. K.; Kim, S.

    2017-12-01

    The recent increase in surface particulate matter (PM) concentrations in South Korea is intriguing due to its disagreement with current intensive emission reduction efforts. The long-term trend of surface PM concentrations in South Korea declined in the 2000s, but since 2012 its concentrations have tended to increase, resulting in frequent severe haze events in the region. This study demonstrates that the interannual variation of surface PM concentrations in South Korea is not only affected by changes in local or regional emission sources, but also closely linked with the interannual variations in regional ventilation. Using EPA Community Multiscale Air Quality modeling system, a 12-year (2004-2015) regional air quality simulation was conducted to assess the impact of the meteorological conditions under constant anthropogenic emissions. In addition, NOAA HYSPLIT dispersion model was utilized to estimate the strength of regional ventilation that dissipates local pollutions. Simulated PM concentrations show a strong negative correlation (i.e. R=-0.86) with regional wind speed, implying that reduced regional ventilation is likely associated with more stagnant conditions that cause severe pollutant episodes in South Korea. We conclude that the current PM concentration trend in South Korea is a combination of long-term decline by emission control efforts and short-term fluctuations in regional wind speed interannual variability. When the meteorology-driven variations are removed, PM concentrations in South Korea have declined continuously even after 2012, with -1.45±0.12, -1.41±0.16, and -1.09±0.16 mg/m3 per year in Seoul, the Seoul Metropolitan Area, and South Korea, respectively.

  20. The Spatial Variation of Dust Particulate Matter Concentrations during Two Icelandic Dust Storms in 2015

    Directory of Open Access Journals (Sweden)

    Pavla Dagsson-Waldhauserova

    2016-06-01

    Full Text Available Particulate matter mass concentrations and size fractions of PM1, PM2.5, PM4, PM10, and PM15 measured in transversal horizontal profile of two dust storms in southwestern Iceland are presented. Images from a camera network were used to estimate the visibility and spatial extent of measured dust events. Numerical simulations were used to calculate the total dust flux from the sources as 180,000 and 280,000 tons for each storm. The mean PM15 concentrations inside of the dust plumes varied from 10 to 1600 µg·m−3 (PM10 = 7 to 583 µg·m−3. The mean PM1 concentrations were 97–241 µg·m−3 with a maximum of 261 µg·m−3 for the first storm. The PM1/PM2.5 ratios of >0.9 and PM1/PM10 ratios of 0.34–0.63 show that suspension of volcanic materials in Iceland causes air pollution with extremely high PM1 concentrations, similar to polluted urban areas in Europe or Asia. Icelandic volcanic dust consists of a higher proportion of submicron particles compared to crustal dust. Both dust storms occurred in relatively densely inhabited areas of Iceland. First results on size partitioning of Icelandic dust presented here should challenge health authorities to enhance research in relation to dust and shows the need for public dust warning systems.

  1. Production of volatile fatty acid in the rumen and its relationship with their concentration, intake of dry matter and digestible organic matter in buffalo (Bos bubalis) calves

    International Nuclear Information System (INIS)

    Verma, D.N.; Singh, U.B.

    1979-01-01

    The production rates of total volatile fatty acid (TVFA) in the rumen of buffalo (Bos bubalis) calves were estimated using a single injection isotope dilution technique. A series of twelve experiments were done with animals given wheat straw and concentrate mixture. The production rate of TVFA ranged from 19.77 to 24.84 moles/d depending upon the amount of food consumed by the animals. Highly significant correlations were observed between TVFA production and their concentration, dry matter and digestible organic matter intake. (auth.)

  2. ACCURATE UNIVERSAL MODELS FOR THE MASS ACCRETION HISTORIES AND CONCENTRATIONS OF DARK MATTER HALOS

    International Nuclear Information System (INIS)

    Zhao, D. H.; Jing, Y. P.; Mo, H. J.; Boerner, G.

    2009-01-01

    A large amount of observations have constrained cosmological parameters and the initial density fluctuation spectrum to a very high accuracy. However, cosmological parameters change with time and the power index of the power spectrum dramatically varies with mass scale in the so-called concordance ΛCDM cosmology. Thus, any successful model for its structural evolution should work well simultaneously for various cosmological models and different power spectra. We use a large set of high-resolution N-body simulations of a variety of structure formation models (scale-free, standard CDM, open CDM, and ΛCDM) to study the mass accretion histories, the mass and redshift dependence of concentrations, and the concentration evolution histories of dark matter halos. We find that there is significant disagreement between the much-used empirical models in the literature and our simulations. Based on our simulation results, we find that the mass accretion rate of a halo is tightly correlated with a simple function of its mass, the redshift, parameters of the cosmology, and of the initial density fluctuation spectrum, which correctly disentangles the effects of all these factors and halo environments. We also find that the concentration of a halo is strongly correlated with the universe age when its progenitor on the mass accretion history first reaches 4% of its current mass. According to these correlations, we develop new empirical models for both the mass accretion histories and the concentration evolution histories of dark matter halos, and the latter can also be used to predict the mass and redshift dependence of halo concentrations. These models are accurate and universal: the same set of model parameters works well for different cosmological models and for halos of different masses at different redshifts, and in the ΛCDM case the model predictions match the simulation results very well even though halo mass is traced to about 0.0005 times the final mass, when

  3. New Extraterrestrial Signature of the Insoluble Organic Matter of the Orgueil, Murchison and Tagish Lake Meteorites as Revealed by Electron Paramagnetic Resonance

    Science.gov (United States)

    Binet, L.; Gourier, D.; Derenne, S.; Robert, F.; Ciofini, I.

    2003-03-01

    EPR of the insoluble organic matter (IOM) of three chondrites revealed heterogeneously spread radicals including diradicaloids. These features not observed in terrestrial kerogens appear as an extraterrestrial signature of the chondritic IOM.

  4. Spatiotemporal distribution and short-term trends of particulate matter concentration over China, 2006-2010.

    Science.gov (United States)

    Yao, Ling; Lu, Ning

    2014-01-01

    the high-level regions distribute in Guangdong, Shanghai, and Tianjin, while the latter in Hebei, Chongqing, and Shandong provinces. Further studies may consider optimizing concentration estimation model and use it to discuss the effects of particulate matters on human health.

  5. Black carbon and particulate matter (PM2.5) concentrations in New York City's subway stations.

    Science.gov (United States)

    Vilcassim, M J Ruzmyn; Thurston, George D; Peltier, Richard E; Gordon, Terry

    2014-12-16

    The New York City (NYC) subway is the main mode of transport for over 5 million passengers on an average weekday. Therefore, airborne pollutants in the subway stations could have a significant impact on commuters and subway workers. This study looked at black carbon (BC) and particulate matter (PM2.5) concentrations in selected subway stations in Manhattan. BC and PM2.5 levels were measured in real time using a Micro-Aethalometer and a PDR-1500 DataRAM, respectively. Simultaneous samples were also collected on quartz filters for organic and elemental carbon (OC/EC) analysis and on Teflon filters for gravimetric and trace element analysis. In the underground subway stations, mean real time BC concentrations ranged from 5 to 23 μg/m(3), with 1 min average peaks >100 μg/m(3), while real time PM2.5 levels ranged from 35 to 200 μg/m(3). Mean EC levels ranged from 9 to 12.5 μg/m(3). At street level on the same days, the mean BC and PM2.5 concentrations were below 3 and 10 μg/m(3), respectively. This study shows that both BC soot and PM levels in NYC's subways are considerably higher than ambient urban street levels and that further monitoring and investigation of BC and PM subway exposures are warranted.

  6. Nitrogen removal capacity and bacterial community dynamics of a Canon biofilter system at different organic matter concentrations.

    Science.gov (United States)

    García-Ruiz, María J; Maza-Márquez, Paula; González-López, Jesús; Osorio, Francisco

    2018-02-01

    Three Canon bench-scale bioreactors with a volume of 2 L operating in parallel were configured as submerged biofilters. In the present study we investigated the effects of a high ammonium concentration (320 mgNH 4 + · L -1 ) and different concentrations of organic matter (0, 100 and 400 mgCOD·L -1 ) on the nitrogen removal capacity and the bacterial community structure. After 60 days, the Canon biofilters operated properly under concentrations of 0 and 100 mgCOD·L -1 of organic matter, with nitrogen removal efficiencies up to 85%. However, a higher concentration of organic matter (400 mgCOD·L -1 ) produced a partial inhibition of nitrogen removal (68.1% efficiency). The addition of higher concentrations of organic matter a modified the bacterial community structure in the Canon biofilter, increasing the proliferation of heterotrophic bacteria related to the genera of Thauera, Longilinea, Ornatilinea, Thermomarinilinea, unclassified Chlorobiales and Denitratisoma. However, heterotrophic bacteria co-exist with Nitrosomonas and Candidatus Scalindua. Thus, our study confirms the co-existence of different microbial activities (AOB, Anammox and denitrification) and the adaptation of a fixed-biofilm system to different concentrations of organic matter. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Ordinary kriging approach to predicting long-term particulate matter concentrations in seven major Korean cities

    Directory of Open Access Journals (Sweden)

    Sun-Young Kim

    2014-09-01

    Full Text Available Objectives Cohort studies of associations between air pollution and health have used exposure prediction approaches to estimate individual-level concentrations. A common prediction method used in Korean cohort studies is ordinary kriging. In this study, performance of ordinary kriging models for long-term particulate matter less than or equal to 10 μm in diameter (PM10 concentrations in seven major Korean cities was investigated with a focus on spatial prediction ability. Methods We obtained hourly PM10 data for 2010 at 226 urban-ambient monitoring sites in South Korea and computed annual average PM10 concentrations at each site. Given the annual averages, we developed ordinary kriging prediction models for each of the seven major cities and for the entire country by using an exponential covariance reference model and a maximum likelihood estimation method. For model evaluation, cross-validation was performed and mean square error and R-squared (R2 statistics were computed. Results Mean annual average PM10 concentrations in the seven major cities ranged between 45.5 and 66.0 μg/m3 (standard deviation=2.40 and 9.51 μg/m3, respectively. Cross-validated R2 values in Seoul and Busan were 0.31 and 0.23, respectively, whereas the other five cities had R2 values of zero. The national model produced a higher crossvalidated R2 (0.36 than those for the city-specific models. Conclusions In general, the ordinary kriging models performed poorly for the seven major cities and the entire country of South Korea, but the model performance was better in the national model. To improve model performance, future studies should examine different prediction approaches that incorporate PM10 source characteristics.

  8. The Effects of Bus Ridership on Airborne Particulate Matter (PM10 Concentrations

    Directory of Open Access Journals (Sweden)

    Jaeseok Her

    2016-07-01

    Full Text Available Air pollution caused by rapid urbanization and the increased use of private vehicles seriously affects citizens’ health. In order to alleviate air pollution, many cities have replaced diesel buses with compressed natural gas (CNG buses that emit less exhaust gas. Urban planning strategies such as transit-oriented development (TOD posit that reducing private vehicle use and increasing public transportation use would reduce air pollution levels. The present study examined the effects of bus ridership on airborne particulate matter (PM10 concentrations in the capital region of Korea. We interpolated the levels of PM10 from 128 air pollution monitoring stations, utilizing the Kriging method. Spatial regression models were used to estimate the impact of bus ridership on PM10 levels, controlling for physical environment attributes and socio-economic factors. The analysis identified that PM10 concentration levels tend to be lower in areas with greater bus ridership. This result implies that urban and transportation policies designed to promote public transportation may be effective strategies for reducing air pollution.

  9. Impact of banning of two-stroke engines on airborne particulate matter concentrations in Dhaka, Bangladesh.

    Science.gov (United States)

    Begum, Bilkis A; Biswas, Swapan K; Hopke, Philip K

    2006-01-01

    Vehicular air pollution is common in growing metropolitan areas throughout the world. Vehicular emissions of fine particles are particularly harmful because they occur near ground level, close to where people live and work. Two-stroke engines represented an important contribution to the motor vehicle emissions where they constitute approximately half of the total vehicle fleet in Dhaka city. Two-stroke engines have lower fuel efficiency than four-stroke engines, and they emit as much of an order of magnitude and more particulate matter (PM) than four-stroke engines of similar size. To eliminate their impact on air quality, the government of Bangladesh promulgated an order banning all two-stroke engines from the roads in Dhaka starting on December 31, 2002. The effect of the banning of two-stroke engines on airborne PM was studied at the Farm Gate air quality-monitoring station in Dhaka (capital of Bangladesh), a hot spot with very high-pollutant concentrations because of its proximity to major roadways. The samples were collected using a "Gent" stacked filter unit in two fractions of 0-2.2 microm and 2.2-10 microm sizes. Samples of fine and coarse fractions of airborne PM collected from 2000 to 2004 were studied. It has been found that the fine PM and black carbon concentrations decreased from the previous years because of the banning of two-stroke engine baby taxies.

  10. Particulate matter concentrations in residences: an intervention study evaluating stand-alone filters and air conditioners.

    Science.gov (United States)

    Batterman, S; Du, L; Mentz, G; Mukherjee, B; Parker, E; Godwin, C; Chin, J-Y; O'Toole, A; Robins, T; Rowe, Z; Lewis, T

    2012-06-01

    This study, a randomized controlled trial, evaluated the effectiveness of free-standing air filters and window air conditioners (ACs) in 126 low-income households of children with asthma. Households were randomized into a control group, a group receiving a free-standing HEPA filter placed in the child's sleeping area, and a group receiving the filter and a window-mounted AC. Indoor air quality (IAQ) was monitored for week-long periods over three to four seasons. High concentrations of particulate matter (PM) and carbon dioxide were frequently seen. When IAQ was monitored, filters reduced PM levels in the child's bedroom by an average of 50%. Filter use varied greatly among households and declined over time, for example, during weeks when pollutants were monitored, filter use was initially high, averaging 84±27%, but dropped to 63±33% in subsequent seasons. In months when households were not visited, use averaged only 34±30%. Filter effectiveness did not vary in homes with central or room ACs. The study shows that measurements over multiple seasons are needed to characterize air quality and filter performance. The effectiveness of interventions using free-standing air filters depends on occupant behavior, and strategies to ensure filter use should be an integral part of interventions. Environmental tobacco smoke (ETS) increased particulate matter (PM) levels by about 14 μg/m3 and was often detected using ETS-specific tracers despite restrictions on smoking in the house as reported on questionnaires administered to caregivers. PM concentrations depended on season, filter usage, relative humidity, air exchange ratios, number of children, outdoor PM levels, sweeping/dusting, and presence of a central air conditioner (AC). Free-standing air filters can be an effective intervention that provides substantial reductions in PM concentrations if the filters are used. However, filter use was variable across the study population and declined over the study duration, and

  11. Compaction of TOC-rich shales due to kerogen conversion. Implications for fluid flow and overpressure

    International Nuclear Information System (INIS)

    Hanebeck, D.; Krooss, B.M.; Leythaeuser, D.

    1998-01-01

    TOC-rich shales (10% TOC) have been artificially matured at temperatures between 200 and 350 deg C under controlled axial stress (20 - 40 MPa) for up to 350 hours. The volume change of the cylindrical samples was monitored continuously throughout the experiment. The performed experiments showed that the compaction associated with the thermal decomposition of the kerogen is significantly larger under hydrous than under dry pyrolysis conditions. This observation points at an important role of water in the conversion of kerogen. Semi quantitative permeability tests indicated that sample permeability had decreased at least one order of magnitude after the compaction pyrolysis experiments. This permeability reduction in combination with the observed compaction is the most probable mechanism for overpressure formation in TOC-rich source rock sequences. (author)

  12. Concentrations and distributions of metals associated with dissolved organic matter from the Suwannee River (GA, USA)

    Science.gov (United States)

    Kuhn, M. Keshia; Neubauer, Elisabeth; Hofmann, Thilo; von der Kammer, Frank; Aiken, George R.; Maurice, Patricia A.

    2015-01-01

    Concentrations and distributions of metals in Suwannee River (SR) raw filtered surface water (RFSW) and dissolved organic matter (DOM) processed by reverse osmosis (RO), XAD-8 resin (for humic and fulvic acids [FA]), and XAD-4 resin (for “transphilic” acids) were analyzed by asymmetrical flow field-flow fractionation (AsFlFFF). SR samples were compared with DOM samples from Nelson's Creek (NLC), a wetland-draining stream in northern Michigan; previous International Humic Substances Society (IHSS) FA and RO samples from the SR; and an XAD-8 sample from Lake Fryxell (LF), Antarctica. Despite application of cation exchange during sample processing, all XAD and RO samples contained substantial metal concentrations. AsFlFFF fractograms allowed metal distributions to be characterized as a function of DOM component molecular weight (MW). In SR RFSW, Fe, Al, and Cu were primarily associated with intermediate to higher than average MW DOM components. SR RO, XAD-8, and XAD-4 samples from May 2012 showed similar MW trends for Fe and Al but Cu tended to associate more with lower MW DOM. LF DOM had abundant Cu and Zn, perhaps due to amine groups that should be present due to its primarily algal origins. None of the fractograms showed obvious evidence for mineral nanoparticles, although some very small mineral nanoparticles might have been present at trace concentrations. This research suggests that AsFlFFF is important for understanding how metals are distributed in different DOM samples (including IHSS samples), which may be key to metal reactivity and bioavailability.

  13. Pre-treatment and ethanol fermentation potential of olive pulp at different dry matter concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Haagensen, Frank [Bioprocess Science and Technology group, Biocentrum-DTU, Building 227, Technical University of Denmark, 2800 Lyngby (Denmark); Skiadas, Ioannis V.; Gavala, Hariklia N.; Ahring, Birgitte K. [Bioprocess Science and Technology group, Biocentrum-DTU, Building 227, Technical University of Denmark, 2800 Lyngby (Denmark); Copenhagen Institute of Technology (Aalborg University Copenhagen), Section for Sustainable Biotechnology, Department of Biotechnology, Chemistry and Environmental Engineering, Lautrupvang 15, DK 2750 Ballerup (Denmark)

    2009-11-15

    Renewable energy sources have received increased interest from the international community with biomass being one of the oldest and the most promising ones. In the concept of exploitation of agro-industrial residues, the present study investigates the pre-treatment and ethanol fermentation potential of the olive pulp, which is the semi solid residue generated from the two-phase processing of the olives for olive oil production. Wet oxidation and enzymatic hydrolysis have been applied aiming at the enhancement of carbohydrates' bioavailability. Different concentrations of enzymes and enzymatic durations have been tested. Both wet oxidation and enzymic treatment were evaluated based on the ethanol obtained in a subsequent fermentation step by Saccharomyces cerevisiae and Thermoanaerobacter mathranii. It was found that a four-day hydrolysis time was adequate for a satisfactory release of glucose and xylose. The combination of wet oxidation and enzymatic hydrolysis resulted in the glucose and xylose concentration increase of 138 and 444%, respectively, compared to 33 and 15% with only enzymes added. However, the highest ethanol production was obtained when only enzymic pre-treatment was applied, implying that wet oxidation is not a recommended pre-treatment process for olive pulp at the conditions tested. It was also showed that increased dry matter concentration did not have a negative effect on the release of sugars, indicating that the cellulose and xylan content of the olive pulp is relatively easily available. The results of the experiments in batch processes clearly emphasize that the simultaneous saccharification and fermentation (SSF) mode is advantageous in comparison with the separate hydrolysis and fermentation (SHF) mode concerning process contamination. (author)

  14. Molecular Simulation of Shale Gas Adsorption onto Overmature Type II Model Kerogen with Control Microporosity.

    Czech Academy of Sciences Publication Activity Database

    Michalec, Lukáš; Lísal, Martin

    2017-01-01

    Roč. 115, 9-12 (2017), s. 1086-1103 ISSN 0026-8976 R&D Projects: GA ČR(CZ) GA16-12291S EU Projects: European Commission(XE) 640979 - ShaleXenvironmenT Institutional support: RVO:67985858 Keywords : barnett shale * clay * multiscale kerogen model Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 1.870, year: 2016

  15. Nanostructural control of methane release in kerogen and its implications to wellbore production decline

    Science.gov (United States)

    Ho, Tuan Anh; Criscenti, Louise J.; Wang, Yifeng

    2016-06-01

    Despite massive success of shale gas production in the US in the last few decades there are still major concerns with the steep decline in wellbore production and the large uncertainty in a long-term projection of decline curves. A reliable projection must rely on a mechanistic understanding of methane release in shale matrix-a limiting step in shale gas extraction. Using molecular simulations, we here show that methane release in nanoporous kerogen matrix is characterized by fast release of pressurized free gas (accounting for ~30-47% recovery) followed by slow release of adsorbed gas as the gas pressure decreases. The first stage is driven by the gas pressure gradient while the second stage is controlled by gas desorption and diffusion. We further show that diffusion of all methane in nanoporous kerogen behaves differently from the bulk phase, with much smaller diffusion coefficients. The MD simulations also indicate that a significant fraction (3-35%) of methane deposited in kerogen can potentially become trapped in isolated nanopores and thus not recoverable. Our results shed a new light on mechanistic understanding gas release and production decline in unconventional reservoirs. The long-term production decline appears controlled by the second stage of gas release.

  16. Seasonal variations in the concentration and solubility of elements in atmospheric particulate matter: a case study in Northern Italy

    Directory of Open Access Journals (Sweden)

    Canepari S.

    2013-04-01

    Full Text Available Atmospheric particulate matter is characterized by a variety of chemical components, generally produced by different sources. Chemical fractionation of elements, namely the determination of their extractable and residual fractions, may reliably increase the selectivity of some elements as tracers of specific PM sources. Seasonal variations of atmospheric particulate matter concentration in PM10 and PM2.5, of elemental concentration in PM10 and PM2.5, of the extractable and residual fraction of elements in different size fractions in the range 0.18 – 18 μm are reported in this paper. The effect of the ageing of the air masses is discussed.

  17. Effect of incorporation of walnut cake (Juglans regia in concentrate mixture on degradation of dry matter, organic matter and production of microbial biomass in vitro in goat

    Directory of Open Access Journals (Sweden)

    Mohsin Ahmad Mir

    2015-10-01

    Full Text Available Aim: This study was carried out to investigate the effect of incorporation of different level of walnut cake in concentrate mixture on in vitro dry matter degradation in order to determine its level of supplementation in ruminant ration. Materials and Methods: Walnut cake was used @ 0, 10, 15, 20, 25 and 30% level to formulate an iso-nitrogenous concentrate mixtures and designated as T1, T2, T3, T4, T5 and T6 respectively. The different formulae of concentrate mixtures were used for in vitro gas production studies using goat rumen liquor with wheat straw in 40:60 ratio. Proximate composition, fiber fractionation and calcium and phosphrous content of walnut cake were estimated. Result: The per cent IVDMD value of T1 and T2 diets was 68.42 ± 1.20 and 67.25 ± 1.37 respectively which was found highest (P<0.05 T3, T4, T5 and T6. Similar trend was also found for TDOM and MBP. Inclusion of walnut cake at 10% level in the concentrate mixture does not affect in vitro dry matter digestibility (IVDMD, truly degradable organic matter (TDOM, mg/200 mg DM, total gas production, microbial biomass production (MBP and efficiency of microbial biomass production (EMP. Conclusion: It is concluded that walnut cake incorporation up to 10% level in the iso -nitrogenous concentrate mixture has no any negative effect on in vitro digestibility of dry matter (DM, TDOM, MBP, EMP and total gas production in goat.

  18. Uncertainty associated with the gravimetric measurement of particulate matter concentration in ambient air.

    Science.gov (United States)

    Lacey, Ronald E; Faulkner, William Brock

    2015-07-01

    matter (PM) concentrations approach regulatory limits, the uncertainty of the measurement is essential in determining the sample size and the probability of type II errors in hypothesis testing. This is an important factor in determining if ambient PM concentrations exceed regulatory limits. The technique described in this paper can be applied to other measurement systems and is especially useful where there are no methods available to generate these values empirically.

  19. Particulate matter concentration mapping from MODIS satellite data: a Vietnamese case study

    International Nuclear Information System (INIS)

    Nguyen, Thanh T N; Bui, Hung Q; Pham, Ha V; Luu, Hung V; Man, Chuc D; Pham, Hai N; Le, Ha T; Nguyen, Thuy T

    2015-01-01

    Particulate Matter (PM) pollution is one of the most important air quality concerns in Vietnam. In this study, we integrate ground-based measurements, meteorological and satellite data to map temporal PM concentrations at a 10 × 10 km grid for the entire of Vietnam. We specifically used MODIS Aqua and Terra data and developed statistically-significant regression models to map and extend the ground-based PM concentrations. We validated our models over diverse geographic provinces i.e., North East, Red River Delta, North Central Coast and South Central Coast in Vietnam. Validation suggested good results for satellite-derived PM 2.5 data compared to ground-based PM 2.5 (n = 285, r 2  = 0.411, RMSE = 20.299 μg m −3 and RE = 39.789%). Further, validation of satellite-derived PM 2.5 on two independent datasets for North East and South Central Coast suggested similar results (n = 40, r 2  = 0.455, RMSE = 21.512 μg m −3 , RE = 45.236% and n = 45, r 2  = 0.444, RMSE = 8.551 μg m −3 , RE = 46.446% respectively). Also, our satellite-derived PM 2.5 maps were able to replicate seasonal and spatial trends of ground-based measurements in four different regions. Our results highlight the potential use of MODIS datasets for PM estimation at a regional scale in Vietnam. However, model limitation in capturing maximal or minimal PM 2.5 peaks needs further investigations on ground data, atmospheric conditions and physical aspects. (letter)

  20. Particulate matter concentration mapping from MODIS satellite data: a Vietnamese case study

    Science.gov (United States)

    Nguyen, Thanh T. N.; Bui, Hung Q.; Pham, Ha V.; Luu, Hung V.; Man, Chuc D.; Pham, Hai N.; Le, Ha T.; Nguyen, Thuy T.

    2015-09-01

    Particulate Matter (PM) pollution is one of the most important air quality concerns in Vietnam. In this study, we integrate ground-based measurements, meteorological and satellite data to map temporal PM concentrations at a 10 × 10 km grid for the entire of Vietnam. We specifically used MODIS Aqua and Terra data and developed statistically-significant regression models to map and extend the ground-based PM concentrations. We validated our models over diverse geographic provinces i.e., North East, Red River Delta, North Central Coast and South Central Coast in Vietnam. Validation suggested good results for satellite-derived PM2.5 data compared to ground-based PM2.5 (n = 285, r2 = 0.411, RMSE = 20.299 μg m-3 and RE = 39.789%). Further, validation of satellite-derived PM2.5 on two independent datasets for North East and South Central Coast suggested similar results (n = 40, r2 = 0.455, RMSE = 21.512 μg m-3, RE = 45.236% and n = 45, r2 = 0.444, RMSE = 8.551 μg m-3, RE = 46.446% respectively). Also, our satellite-derived PM2.5 maps were able to replicate seasonal and spatial trends of ground-based measurements in four different regions. Our results highlight the potential use of MODIS datasets for PM estimation at a regional scale in Vietnam. However, model limitation in capturing maximal or minimal PM2.5 peaks needs further investigations on ground data, atmospheric conditions and physical aspects.

  1. Emission Sectoral Contributions of Foreign Emissions to Particulate Matter Concentrations over South Korea

    Science.gov (United States)

    Kim, E.; Kim, S.; Kim, H. C.; Kim, B. U.; Cho, J. H.; Woo, J. H.

    2017-12-01

    In this study, we investigated the contributions of major emission source categories located upwind of South Korea to Particulate Matter (PM) in South Korea. In general, air quality in South Korea is affected by anthropogenic air pollutants emitted from foreign countries including China. Some studies reported that foreign emissions contributed 50 % of annual surface PM total mass concentrations in the Seoul Metropolitan Area, South Korea in 2014. Previous studies examined PM contributions of foreign emissions from all sectors considering meteorological variations. However, little studies conducted to assess contributions of specific foreign source categories. Therefore, we attempted to estimate sectoral contributions of foreign emissions from China to South Korea PM using our air quality forecasting system. We used Model Inter-Comparison Study in Asia 2010 for foreign emissions and Clean Air Policy Support System 2010 emission inventories for domestic emissions. To quantify contributions of major emission sectors to South Korea PM, we applied the Community Multi-scale Air Quality system with brute force method by perturbing emissions from industrial, residential, fossil-fuel power plants, transportation, and agriculture sectors in China. We noted that industrial sector was pre-dominant over the region except during cold season for primary PMs when residential emissions drastically increase due to heating demand. This study will benefit ensemble air quality forecasting and refined control strategy design by providing quantitative assessment on seasonal contributions of foreign emissions from major source categories.

  2. Using ground-based spectral reflectance sensors and photography to estimate shoot N concentration and dry matter of potato

    DEFF Research Database (Denmark)

    Zhenjiang, Zhou; Jabloun, Mohamed; Plauborg, Finn

    2018-01-01

    Two years experiments were set up to evaluate the performance of different vegetation indices (VI) to estimate shoot N concentration (Nc) and shoot dry matter (DM) for a potato crop grown under different nitrogen (N) treatments. Possibilities to improve the performance of VI using normalization b...

  3. Reduced Orbitofrontal Gray Matter Concentration as a Marker of Premorbid Childhood Trauma in Cocaine Use Disorder

    Directory of Open Access Journals (Sweden)

    Keren Bachi

    2018-02-01

    Full Text Available Background: Childhood trauma affects neurodevelopment and promotes vulnerability to impaired constraint, depression, and addiction. Reduced gray matter concentration (GMC in the mesocorticolimbic regions implicated in reward processing and cognitive control may be an underlying substrate, as documented separately in addiction and for childhood trauma. The purpose of this study was to understand the contribution of childhood maltreatment to GMC effects in individuals with cocaine use disorder.Methods: Individuals with cocaine use disorder were partitioned into groups of low vs. high childhood trauma based on median split of the total score of the Childhood Trauma Questionnaire (CTQ; CUD-L, N = 23; CUD-H, N = 24 and compared with age, race, and gender matched healthy controls with low trauma (N = 29. GMC was obtained using voxel-based morphometry applied to T1-weighted MRI scans. Drug use, depression and constraint were assessed with standardized instruments.Results: Whole-brain group comparisons showed reduced GMC in the right lateral orbitofrontal cortex (OFC in CUD-H as compared with controls (cluster-level pFWE-corr < 0.001 and CUD-L (cluster-level pFWE-corr = 0.035; there were no significant differences between CUD-L and controls. A hierarchical regression analysis across both CUD groups revealed that childhood trauma, but not demographics and drug use, and beyond constraint and depression, accounted for 37.7% of the variance in the GMC in the right lateral OFC (p < 0.001.Conclusions: Beyond other contributing factors, childhood trauma predicted GMC reductions in the OFC in individuals with cocaine use disorder. These findings underscore a link between premorbid environmental stress and morphological integrity of a brain region central for behaviors underlying drug addiction. These results further highlight the importance of accounting for childhood trauma, potentially as a factor predisposing to addiction, when examining and interpreting

  4. Concentration and movement of neonicotinoids as particulate matter downwind during agricultural practices using air samplers in southwestern Ontario, Canada.

    Science.gov (United States)

    Forero, Luis Gabriel; Limay-Rios, Victor; Xue, Yingen; Schaafsma, Arthur

    2017-12-01

    Atmospheric emissions of neonicotinoid seed treatment insecticides as particulate matter in field crops occur mainly for two reasons: 1) due to abraded dust of treated seed generated during planting using vacuum planters, and 2) as a result of disturbances (tillage or wind events) in the surface of parental soils which release wind erodible soil-bound residues. In the present study, concentration and movement of neonicotinoids as particulate matter were quantified under real conditions using passive and active air samplers. Average neonicotinoid concentrations in Total Suspended Particulate (TSP) using passive samplers were 0.48 ng/cm 2 , trace, trace (LOD 0.80 and 0.04 ng/cm 2 for clothianidin and thiamethoxam, respectively), and using active samplers 16.22, 1.91 and 0.61 ng/m 3 during planting, tillage and wind events, respectively. There was a difference between events on total neonicotinoid concentration collected in particulate matter using either passive or active sampling. Distance of sampling from the source field during planting of treated seed had an effect on total neonicotinoid air concentration. However, during tillage distance did not present an effect on measured concentrations. Using hypothetical scenarios, values of contact exposure for a honey bee were estimated to be in the range from 1.1% to 36.4% of the reference contact LD 50 value of clothianidin of 44 ng/bee. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Effect of catchment land use and soil type on the concentration, quality, and bacterial degradation of riverine dissolved organic matter

    DEFF Research Database (Denmark)

    Autio, Iida; Soinne, Helena; Helin, Janne

    2016-01-01

    We studied the effects of catchment characteristics (soil type and land use) on the concentration and quality of dissolved organic matter (DOM) in river water and on the bacterial degradation of terrestrial DOM. The share of organic soil was the strongest predictor of high concentrations...... of dissolved organic carbon, nitrogen, and phosphorus (DOC, DON, and DOP, respectively), and was linked to DOM quality. Soil type was more important than land use in determining the concentration and quality of riverine DOM. On average, 5–9 % of the DOC and 45 % of the DON were degraded by the bacterial...

  6. Lyophilization, Reconstitution, and DBP Formation in Reverse-Osmosis Concentrated Natural Organic Matter

    Science.gov (United States)

    Drinking water treatment and disinfection byproduct (DBP) research can be complicated by natural organic matter (NOM) temporal variability. NOM preservation by lyophilization (freeze-drying) has been long practiced to address this issue; however, its applicability for drinking w...

  7. Composition and structure of natural organic matter through advanced nuclear magnetic resonance techniques

    Directory of Open Access Journals (Sweden)

    Dainan Zhang

    2017-02-01

    Full Text Available Abstract Natural organic matter (NOM plays important roles in biological, chemical, and physical processes within the terrestrial and aquatic ecosystem. Despite its importance, a clear and exhaustive knowledge on NOM chemistry still lacks. Aiming to prove that advanced solid-state 13C nuclear magnetic resonance (NMR techniques may contribute to fill such a gap, in this paper we reported relevant examples of its applicability to NOM components, such as biomass, deposition material, sediments, and kerogen samples. It is found that nonhydrolyzable organic carbons (NHC, chars, and polymethylene carbons are important in the investigated samples. The structure of each of the NHC fractions is similar to that of kerogens, highlighting the importance of selective preservation of NOM to the kerogen origin in the investigated aquatic ecosystems. Moreover, during the artificial maturation experiments of kerogen, the chemical and structural characteristics such as protonated aromatic, nonprotonated carbons, and aromatic cluster size play important roles in the origin and variation of nanoporosity during kerogen maturation. Graphical abstract NMR parameters of thermally stimulated kerogens

  8. Measured and modelled concentrations and vertical profiles of airborne particulate matter within the boundary layer of a street canyon

    International Nuclear Information System (INIS)

    Colls, J.J.; Micallef, A.

    1999-01-01

    Concentrations and vertical profiles of various fractions of airborne particulate matter (suspended particulate matter (SPM), PM 10 and PM 2.5 ) have been measured over the first three metres from ground in a street canyon. Measurements were carried out using automated near real-time apparatus called the Kinetic Sequential Sampling (KSS) system. KSS system is essentially an electronically-controlled lift carrying a real-time particle monitor for sampling air sequentially, at different heights within the breathing zone, which includes all heights within the surface layer of a street canyon at which people may breathe. Data is automatically logged at the different receptor levels, for the determination of the average vertical concentration profile of airborne particulate matter. For measuring the airborne particle concentration, a Grimm Dust Monitor 1.104/5 was used. The recorded data also allows for time series analysis of airborne particulate matter concentration at different heights. Time series data and hourly-average vertical concentration profiles in the boundary layer of the confines of a street are thought to be mainly determined by traffic emissions and traffic associated processes. Hence the measured data were compared with results of a street canyon emission-dispersion model in time and space. This Street Level Air Quality (SLAQ) model employs the plume-box technique and includes modules for simulating vehicle-generated effects such as thermally- and mechanically-generated turbulence and resuspension of road dust. Environmental processes, such as turbulence resulting from surface sensible heat and the formation of sulphate aerosol from sulphur dioxide exhaust emissions, are taken into account. The paper presents an outline description of the measuring technique and model used, and a comparison of the measured and modelled data

  9. Climate impact on airborne particulate matter concentrations in California using seven year analysis periods

    Directory of Open Access Journals (Sweden)

    A. Mahmud

    2010-11-01

    Full Text Available The effect of global climate change on the annual average concentration of fine particulate matter (PM2.5 in California was studied using a climate-air quality modeling system composed of global through regional models. Output from the NCAR/DOE Parallel Climate Model (PCM generated under the "business as usual" global emissions scenario was downscaled using the Weather Research and Forecasting (WRF model followed by air quality simulations using the UCD/CIT airshed model. The system represents major atmospheric processes acting on gas and particle phase species including meteorological effects on emissions, advection, dispersion, chemical reaction rates, gas-particle conversion, and dry/wet deposition. The air quality simulations were carried out for the entire state of California with a resolution of 8-km for the years 2000–2006 (present climate with present emissions and 2047–2053 (future climate with present emissions. Each of these 7-year analysis periods was analyzed using a total of 1008 simulated days to span a climatologically relevant time period with a practical computational burden. The 7-year windows were chosen to properly account for annual variability with the added benefit that the air quality predictions under the present climate could be compared to actual measurements. The climate-air quality modeling system successfully predicted the spatial pattern of present climate PM2.5 concentrations in California but the absolute magnitude of the annual average PM2.5 concentrations were under-predicted by ~4–39% in the major air basins. The majority of this under-prediction was caused by excess ventilation predicted by PCM-WRF that should be present to the same degree in the current and future time periods so that the net bias introduced into the comparison is minimized.

    Surface temperature, relative humidity (RH, rain rate, and wind speed were predicted to increase in the future climate

  10. Evidence for porphyrins bound, via ester bonds, to the Messel oil shale kerogen by selective chemical degradation experiments

    Science.gov (United States)

    Huseby, B.; Ocampo, R.

    1997-09-01

    High amounts of nickel mono- and di-acid porphyrins were released from Messel oil shale kerogen (Eocene, Germany) by selective chemical degradation (acid and base hydrolysis). The released porphyrin fractions were quantified (UV-vis) and their constituents isolated and characterized at the molecular level (UV-vis, MS, NMR). The mono-acid porphyrin fraction released contained four compounds of similar abundance which arise from an obvious chlorophyll or bacteriochlorophyll precursor. The di-acid porphyrin fraction was, however, dominated by far by one compound, mesoporphyrin IX, which must have originated from heme-like precursors (heme, cytochromes, etc.). These results show unambigously that the released mono- and di-acid porphyrins were linked to the macromolecular kerogen network via ester bonds and suggest that precursor heme-like pigments could be selectively and/or more readily incorporated into the macromolecular kerogen network than precursor chlorophylls and bacteriochlorophylls.

  11. THE HISTORY OF EXPLORATION AND EXPLOITATION OF BITUMINOUS AND KEROGENOUS DEPOSITS IN CROATIA

    Directory of Open Access Journals (Sweden)

    Berislav Šebečić

    1995-12-01

    Full Text Available It is assumed thal the first known sedimens of natural bitumen or asphalt in coastal Croatia were exploited as the early moddle ages. Yet authenticated written documents about Vinišće near Trogir derive from no earlier than 1628, about Vrgorac/Paklina from only 1753. By the end of the 18th century, many deposits were discovered in Dalmatia, but it was Škrip on the Island of Brač and Suhi Dolac that were important. The earliest known deposits and occurrences of kerogenous rocks, or bituminous or oil shales, are mentioned as stone or fossil coal in Sovinjak, in the upper course of the River Mirna, and in Rebići in Istria; near Sinj, Slivno not far from the River Neretva, Mirta and near Nerežišće on the Island uf Brač. All if these were well known and described in 1804, while Sovinjak was mentioned in the 16th century. In the article, some of new information derived from mining and geological research into bituminous and kerogenous sediments and deposits are provided (the paper is published in Croatian.

  12. Heterogeneous carbonaceous matter in sedimentary rock lithocomponents causes significant trichloroethylene (TCE) sorption in a low organic carbon content aquifer/aquitard system.

    Science.gov (United States)

    Choung, Sungwook; Zimmerman, Lisa R; Allen-King, Richelle M; Ligouis, Bertrand; Feenstra, Stanley

    2014-10-15

    This study evaluated the effects of heterogeneous thermally altered carbonaceous matter (CM) on trichloroethylene (TCE) sorption for a low fraction organic carbon content (foc) alluvial sedimentary aquifer and aquitard system (foc=0.046-0.105%). The equilibrium TCE sorption isotherms were highly nonlinear with Freundlich exponents of 0.46-0.58. Kerogen+black carbon was the dominant CM fraction extracted from the sediments and accounted for >60% and 99% of the total in the sands and silt, respectively. Organic petrological examination determined that the kerogen included abundant amorphous organic matter (bituminite), likely of marine origin. The dark calcareous siltstone exhibited the greatest TCE sorption among aquifer lithocomponents and accounted for most sorption in the aquifer. The results suggest that the source of the thermally altered CM, which causes nonlinear sorption, was derived from parent Paleozoic marine carbonate rocks that outcrop throughout much of New York State. A synthetic aquifer-aquitard unit system (10% aquitard) was used to illustrate the effect of the observed nonlinear sorption on mass storage potential at equilibrium. The calculation showed that >80% of TCE mass contained in the aquifer was sorbed on the aquifer sediment at aqueous concentration TCE groundwater plume in the aquifer studied. It is implied that sorption may similarly contribute to TCE persistence in other glacial alluvial aquifers with similar geologic characteristics, i.e., comprised of sedimentary rock lithocomponents that contain thermally altered CM. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Observations of a narrow zone of high suspended particulate matter (SPM) concentrations along the Dutch coast

    NARCIS (Netherlands)

    van der Hout, C.M.; Gerkema, T.; Nauw, J.J.; Ridderinkhof, H.

    2015-01-01

    The objective of the study described in this paper is to localize the transport path of suspended particulate matter (SPM) in the Dutch coastal zone in the southern North Sea. It is known that a large mass of SPM is transported northward from the Strait of Dover, which is however mostly hidden from

  14. Indoor/outdoor Particulate Matter Number and Mass Concentration in Modern Offices

    Czech Academy of Sciences Publication Activity Database

    Chatoutsidou, S.E.; Ondráček, Jakub; Tesař, Ondřej; Tørseth, K.; Ždímal, Vladimír; Lazaridis, M.

    2015-01-01

    Roč. 92, OCT 2015 (2015), s. 462-474 ISSN 0360-1323 EU Projects: European Commission(XE) 315760 Institutional support: RVO:67985858 Keywords : modern offices * particulate matter * mechanical ventilation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.394, year: 2015

  15. From concentration to dose: factors influencing airborne particulate matter deposition in humans and rats

    NARCIS (Netherlands)

    Winter-sorkina R de; Cassee FR; LBV; LBO

    2003-01-01

    Particulate matter (PM) consisting of solid particles and droplets is present in the ambient air. Particles with an aerodynamic diameter less than 10 micro m can be inhaled by humans. Knowledge of the tissue-specific internal dose of PM is a critical link between individual external exposure and

  16. Cardiopulmonary Toxicity Induced by Ambient Particulate Matter (BI City Concentrated Ambient Particle Study)

    Energy Technology Data Exchange (ETDEWEB)

    Annette Rohr; James Wagner Masako Morishita; Gerald Keeler; Jack Harkema

    2010-06-30

    Alterations in heart rate variability (HRV) have been reported in rodents exposed to concentrated ambient particles (CAPs) from different regions of the United States. The goal of this study was to compare alterations in cardiac function induced by CAPs in two distinct regional atmospheres. AirCARE 1, a mobile laboratory with an EPA/Harvard fine particle (particulate matter <2.5 {micro}m; PM{sub 2.5}) concentrator was located in urban Detroit, MI, where the PM mixture is heavily influenced by motor vehicles, and in Steubenville, OH, where PM is derived primarily from long-range transport and transformation of power plant emissions, as well as from local industrial operations. Each city was studied during both winter and summer months, for a total of four sampling periods. Spontaneously hypertensive rats instrumented for electrocardiogram (ECG) telemetry were exposed to CAPs 8 h/day for 13 consecutive days during each sampling period. Heart rate (HR), and indices of HRV (standard deviation of the average normal-to-normal intervals [SDNN]; square root of the mean squared difference of successive normal-to-normal intervals [rMSSD]), were calculated for 30-minute intervals during exposures. A large suite of PM components, including nitrate, sulfate, elemental and organic carbon, and trace elements, were monitored in CAPs and ambient air. In addition, a unique sampler, the Semi-Continuous Elements in Air Sampler (SEAS) was employed to obtain every-30-minute measurements of trace elements. Positive matrix factorization (PMF) methods were applied to estimate source contributions to PM{sub 2.5}. Mixed modeling techniques were employed to determine associations between pollutants/CAPs components and HR and HRV metrics. Mean CAPs concentrations in Detroit were 518 and 357 {micro}g/m{sup 3} (summer and winter, respectively) and 487 and 252 {micro}g/m{sup 3} in Steubenville. In Detroit, significant reductions in SDNN were observed in the summer in association with cement

  17. Disinfection byproduct formation in reverse-osmosis concentrated and lyophilized natural organic matter from a drinking water source.

    Science.gov (United States)

    Pressman, Jonathan G; McCurry, Daniel L; Parvez, Shahid; Rice, Glenn E; Teuschler, Linda K; Miltner, Richard J; Speth, Thomas F

    2012-10-15

    Drinking water treatment and disinfection byproduct (DBP) research can be complicated by natural organic matter (NOM) temporal variability. NOM preservation by lyophilization (freeze-drying) has been long practiced to address this issue; however, its applicability for drinking water research has been limited because the selected NOM sources are atypical of most drinking water sources. The purpose of this research was to demonstrate that reconstituted NOM from a lyophilized reverse-osmosis (RO) concentrate of a typical drinking water source closely represents DBP formation in the original NOM. A preliminary experiment assessed DBP formation kinetics and yields in concentrated NOM, which demonstrated that chlorine decays faster in concentrate, in some cases leading to altered DBP speciation. Potential changes in NOM reactivity caused by lyophilization were evaluated by chlorination of lyophilized and reconstituted NOM, its parent RO concentrate, and the source water. Bromide lost during RO concentration was replaced by adding potassium bromide prior to chlorination. Although total measured DBP formation tended to decrease slightly and unidentified halogenated organic formation tended to increase slightly as a result of RO concentration, the changes associated with lyophilization were minor. In lyophilized NOM reconstituted back to source water TOC levels and then chlorinated, the concentrations of 19 of 21 measured DBPs, constituting 96% of the total identified DBP mass, were statistically indistinguishable from those in the chlorinated source water. Furthermore, the concentrations of 16 of 21 DBPs in lyophilized NOM reconstituted back to the RO concentrate TOC levels, constituting 86% DBP mass, were statistically indistinguishable from those in the RO concentrate. This study suggests that lyophilization can be used to preserve concentrated NOM without substantially altering the precursors to DBP formation. Published by Elsevier Ltd.

  18. Metabolisable protein supply to lactating dairy cows increased with increasing dry matter concentration in grass-clover silage

    DEFF Research Database (Denmark)

    Johansen, Marianne; Hellwing, Anne Louise Frydendahl; Lund, Peter

    2017-01-01

    The aim of this experiment was to study the effect of increased dry matter (DM) concentration in grass-clover silage, obtained by extending the pre-wilting period before ensiling, on the amount of metabolisable protein (MP) supplied to lactating dairy cows. Spring growth and first regrowth of grass...... and faeces, respectively, were collected over 94 h to cover the diurnal variation, pooled, and subsequently analysed. Rumen fluid was collected in same sampling procedure. To estimate the duodenal flow of microbial protein, microbes were isolated from the rumen and analysed for amino acids (AA) and purines...... flow of AA. The higher duodenal flow of AA derived from a lower rumen degradation of feed protein and a tendency towards a higher microbial synthesis in the rumen. Fibre digestibility and CH4 production were not affected by silage DM concentration. In conclusion, MP concentration in grass-clover silage...

  19. Ambient air quality of karachi city as reflected by atmospheric particulate matter (PM/sub 10/) concentrations

    International Nuclear Information System (INIS)

    Hashmi, D.R.; Shareef, A.

    2016-01-01

    The present study examines the variation of ambient aerosol (PM/sub 10/) concentrations in Karachi, city. Samples were collected from ten different locations, representative of urban background, residential, traffic and industrial areas from 2007 to 2011. At each location, PM/sub 10/) was measured continuously from 08:00 am to 06:00 pm at local time. The maximum 10 h average particulate matter (PM/sub 10/) mass concentrations were found at Tibet Centre (440.1 mg/m/sup 3/) and minimum at PCSIR Campus (21.7 mg/m/sup 3/) during 2008. A rising trend during 2008 may be due to the civil works for bridges and extension of roads at different locations in Karachi. The results also suggest that urban traffic and industrial areas appeared to have higher PM/sub 10/) concentration than residential and background areas. (author)

  20. Release of sulfur- and oxygen-bound components from a sulfur-rich kerogen during simulated maturation by hydrous pyrolysis

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Putchew, A.; Schaeffer-Reiss, C.; Schaeffer, P.; Koopmans, M.P.; Leeuw, J.W. de; Lewan, M.D.

    1998-01-01

    An immature sulfur-rich marl from the Gessosso-solfifera Formation of the Vena del Gesso Basin (Messinian, Italy) has been subjected to hydrous pyrolysis (160 to 330°C) to simulate maturation under natural conditions. The kerogen of the unheated and heated samples was isolated and the hydrocarbons

  1. Kerogen chemistry 5. Anhydride formation in, solvent swelling of, and loss of organics on demineralization of Kimmeridge shales

    International Nuclear Information System (INIS)

    Larsen, John W.; Flores, Carlos Islas

    2008-01-01

    The results of three short and related, but experimentally independent, studies of 4 Kimmeridge shales and their kerogens are reported. Differential scanning calorimeter (DSC) studies of the kerogens reveal that three of the four show evidence of anhydride formation when heated at 20 C/min between 50 C and 180 C. There is no regular rank dependence of anhydride formation. After solvent swelling in tetrahydrofuran (THF), extracted organics were isolated from the THF and the recovered kerogens were swollen a second time in fresh THF. The second solvent swelling ratios were slightly larger than the first because the presence of the extracts in the original THF lowers solvent activity thus reducing swelling. The shales were demineralized in the usual way except that methylene chloride was added to dissolve any organics that were liberated from the rock as a consequence of mineral dissolution. Small amounts of organics were found in the methylene chloride supporting Price and Clayton's conclusion that organics are expelled from the kerogen and are present in lacunae in the minerals. (author)

  2. Hierarchical modeling of indoor radon concentration: how much do geology and building factors matter?

    International Nuclear Information System (INIS)

    Borgoni, Riccardo; De Francesco, Davide; De Bartolo, Daniela; Tzavidis, Nikos

    2014-01-01

    Radon is a natural gas known to be the main contributor to natural background radiation exposure and only second to smoking as major leading cause of lung cancer. The main concern is in indoor environments where the gas tends to accumulate and can reach high concentrations. The primary contributor of this gas into the building is from the soil although architectonic characteristics, such as building materials, can largely affect concentration values. Understanding the factors affecting the concentration in dwellings and workplaces is important both in prevention, when the construction of a new building is being planned, and in mitigation when the amount of Radon detected inside a building is too high. In this paper we investigate how several factors, such as geologic typologies of the soil and a range of building characteristics, impact on indoor concentration focusing, in particular, on how concentration changes as a function of the floor level. Adopting a mixed effects model to account for the hierarchical nature of the data, we also quantify the extent to which such measurable factors manage to explain the variability of indoor radon concentration. - Highlights: • It is assessed how the variability of indoor radon concentration depends on buildings and lithologies. • The lithological component has been found less relevant than the building one. • Radon-prone lithologies have been identified. • The effect of the floor where the room is located has been estimated. • Indoor radon concentration have been predicted for different dwelling typologies

  3. Fast-freezing with liquid nitrogen preserves bulk dissolved organic matter concentrations, but not its composition

    DEFF Research Database (Denmark)

    Thieme, Lisa; Graeber, Daniel; Kaupenjohann, Martin

    2016-01-01

    -freezing with liquid nitrogen) on DOM concentrations measured as organic carbon (DOC) concentrations and on spectroscopic properties of DOM from different terrestrial ecosystems (forest and grassland). Fresh and differently frozen throughfall, stemflow, litter leachate and soil solution samples were analyzed for DOC...... concentrations, UV-vis absorption and fluorescence excitation–emission matrices combined with parallel factor analysis (PARAFAC). Fast-freezing with liquid nitrogen prevented a significant decrease of DOC concentrations observed after freezing at −18 °C. Nonetheless, the share of PARAFAC components 1 (EXmax...... component 4 (EXmax: 280 nm, EXmax: 328 nm) to total fluorescence was not affected by freezing. We recommend fast-freezing with liquid nitrogen for preservation of bulk DOC concentrations of samples from terrestrial sources, whereas immediate measuring is preferable to preserve spectroscopic properties...

  4. The Hyades cluster-supercluster connection - Evidence for a local concentration of dark matter

    Science.gov (United States)

    Casertano, Stefano; Iben, Icko, Jr.; Shiels, Aaron

    1993-01-01

    Stars that evaporate from the Hyades cluster will remain within a few hundred parsecs of the cluster only if they are dynamically bound to a much more massive entity containing the cluster. A local mass enhancement of at least (5-10) x 10 exp 5 solar masses, with a radius of about 100 pc, can trap stars with an origin related to that of the Hyades cluster and explains the excess of stars with velocities near the Hyades velocity that constitutes the Hyades supercluster. Part of this mass enhancement can be in visible stars, but a substantial fraction is likely to be in the form of dark matter.

  5. PIXE and neutron activation analysis: intercomparison in the elemental concentration of airborne particulate matter

    International Nuclear Information System (INIS)

    Cassorla, V.; Rojas, X.; Gras, N.; Chuaqui, L.; Dinator, M.I.; Morales, J.R.; Llona, F.; Romo-Kroeger, C.

    1993-01-01

    Two nuclear analytical techniques, neutron activation analysis (NAA) and proton induced X-ray emission (PIXE), were used to determine major and trace elements in airborne particulate matter collected during the first fortnight of June 1991 at the La Reina Nuclear Center. NAA detected the presence of 15 elements in the samples. PIXE, for the same samples, allowed the detection of 12 elements. The elements determined by both techniques were Al, Ca, Mn, Fe, Cu, and Zn. A good correlation between results for these elements for each of the two techniques was demonstrated. (author)

  6. Seasonal variation of organic matter concentration and characteristics in the Maji ya Chai River (Tanzania): Impact on treatability by ultrafiltration

    KAUST Repository

    Aschermann, Geert

    2016-05-07

    Many waters in Tanzania exhibit high concentrations of organic matter and dissolved contaminants such as fluoride. Due to bacteria and virus removal, ultrafiltration (UF) is an attractive option for drinking water treatment, and when coupled with adsorbents, may compete with other established processes like nanofiltration (NF) for lower contaminant concentrations. The results presented here examine the characteristics and treatability of tropical natural organic matter (NOM) by UF as a function of seasonal variation. The Tanzanian river Maji ya Chai was sampled monthly during one year. The composition of NOM in Maji ya Chai River is influenced strongly by precipitation. Total organic carbon (TOC), specific ultraviolet absorbance (SUVA) and concentration of allochthonous organics substances (such as humic substances (HS)) are elevated in periods following high precipitation, while TOC is lower and contains more biopolymers in the dry seasons. UF experiments with two regenerated cellulose membranes of different molecular weight cut-off (MWCO, 5 and 10 kDa) were conducted. UF is able to remove 50–95% of TOC with a seasonal variability of 10–20%. Due to the remaining NOM in the water that would contribute to disinfection by-product formation and bacterial regrowth, the physically disinfected water is more applicable for point of use systems than distribution or storage.

  7. Changes in feedwater organic matter concentrations based on intake type and pretreatment processes at SWRO facilities, Red Sea, Saudi Arabia

    KAUST Repository

    Dehwah, Abdullah

    2015-03-01

    Transparent exopolymer particles (TEP), natural organic matter, and bacterial concentrations in feedwater are important factors that can lead to membrane biofouling in seawater reverse osmosis (SWRO) systems. Two methods for controlling these concentrations in the feedwater prior to pretreatment have been suggested; use of subsurface intake systems or placement of the intake at a greater depth in the sea. These proposed solutions were tested at two SWRO facilities located along the Red Sea of Saudi Arabia. A shallow well intake system was very effective in reducing the algae and bacterial concentrations and somewhat effective in reducing TEP concentrations. An intake placed at a depth of 9. m below the surface was found to have limited impact on improving water quality compared to a surface intake. The algae and bacteria concentration in the feedwater (deep) was lower compared to the surface seawater, but the overall TEP concentration was higher. Bacteria and TEP measurements made in the pretreatment process train in the plant and after the cartridge filters suggest that regrowth of bacteria is occurring within the cartridge filters.

  8. Factors determining the concentration and chemical composition of particulate matter in the air of selected service facilities

    Science.gov (United States)

    Rogula-Kopiec, Patrycja; Pastuszka, Józef; Mathews, Barbara; Widziewicz, Kamila

    2018-01-01

    The link between increased morbidity and mortality and increasing concentrations of particulate matter (PM) resulted in great attention being paid to the presence and physicochemical properties of PM in closed rooms, where people spends most of their time. The least recognized group of such indoor environments are small service facilities. The aim of this study was to identify factors which determine the concentration, chemical composition and sources of PM in the air of different service facilities: restaurant kitchen, printing office and beauty salon. The average PM concentration measured in the kitchen was 5-fold (PM4, particle fraction ≥ 4 μm) and 5.3-fold (TSP, total PM) greater than the average concentration of these PM fractions over the same period. During the same measurement period in the printing office and in the beauty salon, the mean PM concentration was 10- and 4-fold (PM4) and 8- and 3-fold (TSP) respectively greater than the mean concentration of these PM fractions in outdoor air. In both facilities the main source of PM macro-components, especially organic carbon, were chemicals, which are normally used in such places - solvents, varnishes, paints, etc. The influence of some metals inflow from the outdoor air into indoor environment of those facilities was also recognized.

  9. Impacts of roadway emissions on urban particulate matter concentrations in sub-Saharan Africa: new evidence from Nairobi, Kenya

    International Nuclear Information System (INIS)

    Vliet, E D S van; Kinney, P L

    2007-01-01

    Air quality is a serious and worsening problem in the rapidly growing cities of sub-Saharan Africa (SSA). However, the lack of ambient monitoring data, and particularly urban roadside concentrations for particulate matter in SSA cities severely hinders our ability to describe temporal and spatial patterns of concentrations, characterize exposure-response relationships for key health outcomes, estimate disease burdens, and promote policy initiatives to address air quality. As part of a collaborative transportation planning exercise between Columbia University and University of Nairobi, air monitoring was carried out in February 2006 in Nairobi, Kenya. The objective of the monitoring was to collect pilot data on air concentrations (PM 2.5 and black carbon) encountered while driving in the Nairobi metropolitan area, and to compare those data to simultaneous 'urban background' concentrations measured in Nairobi but away from roadways. For both the background and roadway monitoring, we used portable air sampling systems that collect integrated filter samples. Results from this pilot study found that roadway concentrations of PM 2.5 were approximately 20-fold higher than those from the urban background site, whereas black carbon concentrations differed by 10-fold. If confirmed by more extensive sampling, these data would underscore the need for air quality and transportation planning and management directed at mitigating roadway pollution

  10. Impacts of roadway emissions on urban particulate matter concentrations in sub-Saharan Africa: new evidence from Nairobi, Kenya

    Science.gov (United States)

    van Vliet, E. D. S.; Kinney, P. L.

    2007-10-01

    Air quality is a serious and worsening problem in the rapidly growing cities of sub-Saharan Africa (SSA). However, the lack of ambient monitoring data, and particularly urban roadside concentrations for particulate matter in SSA cities severely hinders our ability to describe temporal and spatial patterns of concentrations, characterize exposure response relationships for key health outcomes, estimate disease burdens, and promote policy initiatives to address air quality. As part of a collaborative transportation planning exercise between Columbia University and the University of Nairobi, air monitoring was carried out in February 2006 in Nairobi, Kenya. The objective of the monitoring was to collect pilot data on air concentrations (PM2.5 and black carbon) encountered while driving in the Nairobi metropolitan area, and to compare those data to simultaneous 'urban background' concentrations measured in Nairobi but away from roadways. For both the background and roadway monitoring, we used portable air sampling systems that collect integrated filter samples. Results from this pilot study found that roadway concentrations of PM2.5 were approximately 20-fold higher than those from the urban background site, whereas black carbon concentrations differed by 10-fold. If confirmed by more extensive sampling, these data would underscore the need for air quality and transportation planning and management directed at mitigating roadway pollution.

  11. Changes in feedwater organic matter concentrations based on intake type and pretreatment processes at SWRO facilities, Red Sea, Saudi Arabia

    KAUST Repository

    Dehwah, Abdullah; Li, Sheng; Almashharawi, Samir; Winters, Harvey; Missimer, Thomas M.

    2015-01-01

    Transparent exopolymer particles (TEP), natural organic matter, and bacterial concentrations in feedwater are important factors that can lead to membrane biofouling in seawater reverse osmosis (SWRO) systems. Two methods for controlling these concentrations in the feedwater prior to pretreatment have been suggested; use of subsurface intake systems or placement of the intake at a greater depth in the sea. These proposed solutions were tested at two SWRO facilities located along the Red Sea of Saudi Arabia. A shallow well intake system was very effective in reducing the algae and bacterial concentrations and somewhat effective in reducing TEP concentrations. An intake placed at a depth of 9. m below the surface was found to have limited impact on improving water quality compared to a surface intake. The algae and bacteria concentration in the feedwater (deep) was lower compared to the surface seawater, but the overall TEP concentration was higher. Bacteria and TEP measurements made in the pretreatment process train in the plant and after the cartridge filters suggest that regrowth of bacteria is occurring within the cartridge filters.

  12. RUMINAL DRY MATTER DEGRADABILITY OF HIGH CONCENTRATE DIETS WITH INCREASING LEVELS OF CALCIUM SOAPS OF TALLOW

    Directory of Open Access Journals (Sweden)

    Jaime Salinas-Chavira

    2012-12-01

    Full Text Available The present study measured the in situ digestibility and ruminal degradability of dry matter of rations with different levels of calcium soaps of tallow (CST. The samples of the four rations with CST at levels of 0% (T1, 1.5% (T2, 3.0% (T3 or 4.5% (T4 were incubated in the rumen of a fistulated yearling steer. The nylon bag technique was used to determine the in situ digestibility and ruminal dry matter degradability. A completely randomized design was used, with 4 treatment diets and 4 repetitions. Rapidly-soluble fraction (a or in situ digestibility of DM at 0 h of incubation was higher in T1 than T3 (P0.05. Potential (a+b degradability was similar (P>0.05 between treatments. Effective degradation modeled at low ruminal turnover (1%/h was lower in T4 than T1 (P0.05. In conclusion, CST in the ration influenced ruminal fermentation during the first hours of incubation. However, effective degradability at medium and high ruminal turnover was not affected by CST level in diets.

  13. Hierarchical modeling of indoor radon concentration: how much do geology and building factors matter?

    Science.gov (United States)

    Borgoni, Riccardo; De Francesco, Davide; De Bartolo, Daniela; Tzavidis, Nikos

    2014-12-01

    Radon is a natural gas known to be the main contributor to natural background radiation exposure and only second to smoking as major leading cause of lung cancer. The main concern is in indoor environments where the gas tends to accumulate and can reach high concentrations. The primary contributor of this gas into the building is from the soil although architectonic characteristics, such as building materials, can largely affect concentration values. Understanding the factors affecting the concentration in dwellings and workplaces is important both in prevention, when the construction of a new building is being planned, and in mitigation when the amount of Radon detected inside a building is too high. In this paper we investigate how several factors, such as geologic typologies of the soil and a range of building characteristics, impact on indoor concentration focusing, in particular, on how concentration changes as a function of the floor level. Adopting a mixed effects model to account for the hierarchical nature of the data, we also quantify the extent to which such measurable factors manage to explain the variability of indoor radon concentration. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Effects of CO2 injection and Kerogen Maturation on Low-Field Nuclear Magnetic Resonance Response

    Science.gov (United States)

    Prasad, M.; Livo, K.

    2017-12-01

    Low-field Nuclear Magnetic Resonance (NMR) is commonly used in petrophysical analysis of petroleum reservoir rocks. NMR experiments record the relaxation and polarization of in-situ hydrogen protons present in gaseous phases such as free-gas intervals and solution gas fluids, bulk fluid phases such as oil and aquifer intervals, and immovable fractions of kerogen and bitumen. Analysis of NMR relaxation spectra is performed to record how fluid composition, maturity, and viscosity change NMR experimental results. We present T1-T2 maps as thermal maturity of a water-saturated, sub-mature Woodford shale is increased at temperatures from 125 to 400 degrees Celsius. Experiments with applied fluid pressure in paraffinic mineral oil and DI water with varying fluid pH have been performed to mimic reservoir conditions in analysis of the relaxation of bulk fluid phases. We have recorded NMR spectra, T1-T2 maps, and fluid diffusion coefficients using a low-field (2 MHz) MagritekTM NMR. CO2 was injected at a pressure of 900 psi in an in house developed NMR pressure vessel made of torlon plastic. Observable 2D NMR shifts in immature kerogen formations as thermal maturity is increased show generation of lighter oils with increased maturity. CO2 injection leads to a decrease in bulk fluid relaxation time that is attributed to viscosity modification with gas presence. pH variation with increased CO2 presence were shown to not effect NMR spectra. From this, fluid properties have been shown to greatly affect NMR readings and must be taken into account for more accurate NMR reservoir characterization.

  15. Comparing oxidative and dilute acid wet explosion pretreatment of Cocksfoot grass at high dry matter concentration for cellulosic ethanol production

    DEFF Research Database (Denmark)

    Njoku, Stephen Ikechukwu; Uellendahl, Hinrich; Ahring, Birgitte Kiær

    2013-01-01

    into cellulose monomeric C6 sugars was achieved for WEx condition AC-E (180°C, 15 min, and 0.2% sulfuric acid). For that condition, the highest ethanol yield of 197 g/kg DM (97% of theoretical maximum value) was achieved for SSF process by Saccharomyces cerevisiae. However, the highest concentration...... of hemicellulose C5 sugars was found for WEx pretreatment condition O2-A (160°C, 15 min, and 6 bar O2) which means that the highest potential ethanol yield was found at this moderate pretreatment condition with oxygen added. Increasing the pretreatment temperature to 180–190°C with addition of oxygen or dilute...... was investigated for cellulosic ethanol production. The biomass raw materials were pretreated using wet explosion (WEx) at 25% dry matter concentration with addition of oxygen or dilute sulfuric acid. The enzymatic hydrolysis of cellulose was significantly improved after pretreatment. The highest conversion...

  16. Concentration levels and temporal variations of heavy elements in the urban particulate matter of Navi Mumbai, India

    International Nuclear Information System (INIS)

    Kothai, P.; Saradhi, I.V.; Prathibha, P.; Pandit, G.G.; Puranik, V.D.

    2012-01-01

    Coarse and fine fractions of particulate matter (PM) were collected and analysed for trace elements using Instrumental Neutron Activation Analysis and Energy Dispersive X-ray Fluorescence techniques. The result showed high concentrations of Fe, S, Zn and Pb in both the size fractions. The elemental data obtained is used to analyze the temporal and seasonal variations. The trend showed maximum concentrations of PM and metals during winter and minimum during the monsoon season. Enrichment Factor (EF) and source analysis was performed for the same data set to identify the strength of contribution of anthropogenic sources and the possible contributing sources in the study area. EF studies showed high enrichments of Zn, Pb and As in the fine fraction particles. Crustal, vehicular and industrial emissions are identified as the major contributing sources of PM in the study area. (author)

  17. Nighttime residential wood burning evidenced from an indirect method for estimating real-time concentration of particulate organic matter (POM)

    International Nuclear Information System (INIS)

    Sciare, J.; Sarda-Esteve, R.; Favez, O.; Cachier, H.; Aymoz, G.; Laj, P.

    2008-01-01

    Real-time analyzers of selected chemical components (sulfate, nitrate, Black Carbon) and integrative aerosol parameters (particulate matter and light scattering coefficient) were implemented for a 2-week campaign (November-December 2005) in a suburban area of Clermont-Ferrand (France) in order to document fast changes in the chemical composition of submicron aerosols. Measurements of particulate organic matter (POM) were not available in the field but were indirectly estimated from time-resolved (3-min) reconstruction of the light scattering coefficient. This methodology offered the opportunity to investigate almost real-time and artifact-free POM concentrations even at low concentrations (typically below 0.1 mu g m(-3)). The overall uncertainties associated with this POM calculation were of the order of 20%, which are comparable to those commonly referred in literature for POM calculation or measurements. A chemical mass balance (CMB) of PM1 was performed using the derived POM concentrations and showed a very good correlation (slope = 0.93; r(2) = 0.91, N = 663) with real-time PM1 measurements obtained from R and P TEOM-FDMS, demonstrating the consistency of our approach. Important diurnal variations were observed in POM concentrations, with a dominant contribution of POM from fossil fuel origin during daytime and a dominant contribution of POM from residential wood burning at night. POM was calculated to contribute as much as 70% of PM1 during our study, pointing out the major role of carbonaceous aerosols at this period of the year at our residential area. (authors)

  18. Production of ethanol from wheat straw by pretreatment and fermentation at high dry matter concentrations

    NARCIS (Netherlands)

    Groenestijn, J.W. van; Slomp, R.S.

    2011-01-01

    High concentrations of substrate and product are important for the economy of second-generation bioethanol production. By a dilute acid thermal pretreatment of large pieces of relatively dry wheat straw using a novel rapid heating method, followed by fed-batch preliquefaction with hydrolytic

  19. Does Concentration Matter for Bank Stability? Evidence from the Albanian Banking Sector

    Directory of Open Access Journals (Sweden)

    Shijaku Gerti

    2017-09-01

    Full Text Available Motivated by the debate on the concentration-stability nexus, this paper studies the impact of bank concentration on the likelihood of a country suffering systemic bank fragility. For this reason, we followed a new approach using on-site bank balance sheet information to construct our proxy that represents each bank stability condition and uses a variety of internal and external factors to estimate a balance panel dynamic two-step General Method of Moments (GMM approach for the period 2008 - 2015. First, results provide supportive evidence consistent with the concentration-fragility view. Second, macroeconomic variables seem to have a significant effect on bank stability, which is not found for the sovereignty primary risk. By contrast, the bank-specific variables have also a significant effect on bank stability conditions. Finally, non-systemic banks are found to be more sensitive to macroeconomic condition and market concentration, while the better capitalised banks are less sensitive to fragility at the expense of lower operation efficiency.

  20. The Effect of Economic Growth, Urbanization, and Industrialization on Fine Particulate Matter (PM2.5) Concentrations in China.

    Science.gov (United States)

    Li, Guangdong; Fang, Chuanglin; Wang, Shaojian; Sun, Siao

    2016-11-01

    Rapid economic growth, industrialization, and urbanization in China have led to extremely severe air pollution that causes increasing negative effects on human health, visibility, and climate change. However, the influence mechanisms of these anthropogenic factors on fine particulate matter (PM 2.5 ) concentrations are poorly understood. In this study, we combined panel data and econometric methods to investigate the main anthropogenic factors that contribute to increasing PM 2.5 concentrations in China at the prefecture level from 1999 to 2011. The results showed that PM 2.5 concentrations and three anthropogenic factors were cointegrated. The panel Fully Modified Least Squares and panel Granger causality test results indicated that economic growth, industrialization, and urbanization increased PM 2.5 concentrations in the long run. The results implied that if China persists in its current development pattern, economic growth, industrialization and urbanization will inevitably lead to increased PM 2.5 emissions in the long term. Industrialization was the principal factor that affected PM 2.5 concentrations for the total panel, the industry-oriented panel and the service-oriented panel. PM 2.5 concentrations can be reduced at the cost of short-term economic growth and industrialization. However, reducing the urbanization level is not an efficient way to decrease PM 2.5 pollutions in the short term. The findings also suggest that a rapid reduction of PM 2.5 concentrations relying solely on adjusting these anthropogenic factors is difficult in a short-term for the heavily PM 2.5 -polluted panel. Moreover, the Chinese government will have to seek much broader policies that favor a decoupling of these coupling relationships.

  1. Characterization and biotoxicity assessment of dissolved organic matter in RO concentrate from a municipal wastewater reclamation reverse osmosis system.

    Science.gov (United States)

    Sun, Ying-Xue; Gao, Yue; Hu, Hong-Ying; Tang, Fang; Yang, Zhe

    2014-12-01

    Reverse osmosis (RO) concentrate from municipal wastewater reclamation reverse osmosis (mWRRO) system containing organic compounds may associate with toxic risk, and its discharge might pose an environmental risk. To identify a basis for the selection of feasible technology in treating RO concentrates, the characteristics and biotoxicity of different fractions of dissolved organic matter (DOM) in RO concentrates from an mWRRO system were investigated. The results indicated that the hydrophilic neutrals (HIN), hydrophobic acids (HOA) and hydrophobic bases (HOB) accounted for 96% of the dissolved organic carbon (DOC) of the total DOM in the RO concentrate. According to the SEC chromatograph detected at 254 nm wavelength of UV, the DOM with molecular weight (MW) 1-3 kDa accounted for the majority of the basic and neutral fractions. The fluorescence spectra of the excitation emission matrix (EEM) indicated that most aromatic proteins, humic/fulvic acid-like and soluble microbial by-product-like substances existed in the fractions HOA and hydrophobic neutrals (HON). The genotoxicity and anti-estrogenic activity of the RO concentrate were 1795.6 ± 57.2 μg 4-NQOL(-1) and 2.19 ± 0.05 mg TAM L(-1), respectively. The HIN, HOA, and HOB contributed to the genotoxicity of the RO concentrate, and the HIN was with the highest genotoxic level of 1007.9 ± 94.8 μg 4-NQOL(-1). The HOA, HON, and HIN lead to the total anti-estrogenic activity of the RO concentrate, and HOA occupied approximately 60% of the total, which was 1.3 ± 0.17 mg TAM L(-1). Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Effects of dissolved organic matter from a eutrophic lake on the freely dissolved concentrations of emerging organic contaminants.

    Science.gov (United States)

    Xiao, Yi-Hua; Huang, Qing-Hui; Vähätalo, Anssi V; Li, Fei-Peng; Chen, Ling

    2014-08-01

    The authors studied the effects of dissolved organic matter (DOM) on the bioavailability of bisphenol A (BPA) and chloramphenicol by measuring the freely dissolved concentrations of the contaminants in solutions containing DOM that had been isolated from a mesocosm in a eutrophic lake. The abundance and aromaticity of the chromophoric DOM increased over the 25-d mesocosm experiment. The BPA freely dissolved concentration was 72.3% lower and the chloramphenicol freely dissolved concentration was 56.2% lower using DOM collected on day 25 than using DOM collected on day 1 of the mesocosm experiment. The freely dissolved concentrations negatively correlated with the ultraviolent absorption coefficient at 254 nm and positively correlated with the spectral slope of chromophoric DOM, suggesting that the bioavailability of these emerging organic contaminants depends on the characteristics of the DOM present. The DOM-water partition coefficients (log KOC ) for the emerging organic contaminants positively correlated with the aromaticity of the DOM, measured as humic acid-like fluorescent components C1 (excitation/emission=250[313]/412 nm) and C2 (excitation/emission=268[379]/456 nm). The authors conclude that the bioavailability of emerging organic contaminants in eutrophic lakes can be affected by changes in the DOM. © 2014 SETAC.

  3. Time-series MODIS image-based retrieval and distribution analysis of total suspended matter concentrations in Lake Taihu (China).

    Science.gov (United States)

    Zhang, Yuchao; Lin, Shan; Liu, Jianping; Qian, Xin; Ge, Yi

    2010-09-01

    Although there has been considerable effort to use remotely sensed images to provide synoptic maps of total suspended matter (TSM), there are limited studies on universal TSM retrieval models. In this paper, we have developed a TSM retrieval model for Lake Taihu using TSM concentrations measured in situ and a time series of quasi-synchronous MODIS 250 m images from 2005. After simple geometric and atmospheric correction, we found a significant relationship (R = 0.8736, N = 166) between in situ measured TSM concentrations and MODIS band normalization difference of band 3 and band 1. From this, we retrieved TSM concentrations in eight regions of Lake Taihu in 2007 and analyzed the characteristic distribution and variation of TSM. Synoptic maps of model-estimated TSM of 2007 showed clear geographical and seasonal variations. TSM in Central Lake and Southern Lakeshore were consistently higher than in other regions, while TSM in East Taihu was generally the lowest among the regions throughout the year. Furthermore, a wide range of TSM concentrations appeared from winter to summer. TSM in winter could be several times that in summer.

  4. Predicting dissolved lignin phenol concentrations in the coastal ocean from chromophoric dissolved organic matter (CDOM absorption coefficients

    Directory of Open Access Journals (Sweden)

    Cédric G. Fichot

    2016-02-01

    Full Text Available Dissolved lignin is a well-established biomarker of terrigenous dissolved organic matter (DOM in the ocean, and a chromophoric component of DOM. Although evidence suggests there is a strong linkage between lignin concentrations and chromophoric DOM (CDOM absorption coefficients in coastal waters, the characteristics of this linkage and the existence of a relationship that is applicable across coastal oceans remain unclear. Here, 421 paired measurements of dissolved lignin concentrations (sum of 9 lignin phenols and CDOM absorption coefficients (ag(λ were used to examine their relationship along the river-ocean continuum (0-37 salinity and across contrasting coastal oceans (sub-tropical, temperate, high-latitude. Overall, lignin concentrations spanned four orders of magnitude and revealed a strong, non-linear relationship with ag(λ. The characteristics of the relationship (shape, wavelength dependency, lignin-composition dependency and evidence from degradation indicators were all consistent with lignin being an important driver of CDOM variability in coastal oceans, and suggested physical mixing and long-term photodegradation were important in shaping the relationship. These observations were used to develop two simple empirical models for estimating lignin concentrations from ag(λ with a +/- 20% error relative to measured values. The models are expected to be applicable in most coastal oceans influenced by terrigenous inputs.

  5. Atmospheric particulate matter size distribution and concentration in West Virginia coal mining and non-mining areas.

    Science.gov (United States)

    Kurth, Laura M; McCawley, Michael; Hendryx, Michael; Lusk, Stephanie

    2014-07-01

    People who live in Appalachian areas where coal mining is prominent have increased health problems compared with people in non-mining areas of Appalachia. Coal mines and related mining activities result in the production of atmospheric particulate matter (PM) that is associated with human health effects. There is a gap in research regarding particle size concentration and distribution to determine respiratory dose around coal mining and non-mining areas. Mass- and number-based size distributions were determined with an Aerodynamic Particle Size and Scanning Mobility Particle Sizer to calculate lung deposition around mining and non-mining areas of West Virginia. Particle number concentrations and deposited lung dose were significantly greater around mining areas compared with non-mining areas, demonstrating elevated risks to humans. The greater dose was correlated with elevated disease rates in the West Virginia mining areas. Number concentrations in the mining areas were comparable to a previously documented urban area where number concentration was associated with respiratory and cardiovascular disease.

  6. Spatiotemporal analysis of particulate matter, sulfur dioxide and carbon monoxide concentrations over the city of Rio de Janeiro, Brazil

    Science.gov (United States)

    Zeri, Marcelo; Oliveira-Júnior, José Francisco; Lyra, Gustavo Bastos

    2011-09-01

    Time series of pollutants and weather variables measured at four sites in the city of Rio de Janeiro, Brazil, between 2002 and 2004, were used to characterize temporal and spatial relationships of air pollution. Concentrations of particulate matter (PM10), sulfur dioxide (SO2) and carbon monoxide (CO) were compared to national and international standards. The annual median concentration of PM10 was higher than the standard set by the World Health Organization (WHO) on all sites and the 24 h means exceeded the standards on several occasions on two sites. SO2 and CO did not exceed the limits, but the daily maximum of CO in one of the stations was 27% higher on weekends compared to weekdays, due to increased activity in a nearby Convention Center. Air temperature and vapor pressure deficit have both presented the highest correlations with pollutant's concentrations. The concentrations of SO2 and CO were not correlated between sites, suggesting that local sources are more important to those pollutants compared to PM10. The time series of pollutants and air temperature were decomposed in time and frequency by wavelet analysis. The results revealed that the common variability of air temperature and PM10 is dominated by temporal scales of 1-8 days, time scales that are associated with the passage of weather events, such as cold fronts.

  7. Dry matter and nitrogen accumulation are not affected by superoptimal concentration of ammonium in flowing solution culture with pH control

    Science.gov (United States)

    Rideout, J. W.; Raper, C. D. Jr; Raper CD, J. r. (Principal Investigator)

    1994-01-01

    While it is known that superoptimal concentrations of the nitrate (NO3-) ion in solution culture do not increase NO3- uptake or dry matter accumulation, the same is not known for the ammonium (NH4+) ion. An experiment was conducted utilizing flowing solution culture with pH control to investigate the influence of superoptimal NH4+ concentrations on dry matter, nitrogen (N), potassium (K), calcium (Ca), and magnesium (Mg) accumulation by nonnodulated soybean plants. Increasing the NH4+ concentration in solution from 1 to 10 mM did not affect dry matter or N accumulation. Accumulations of K, Ca, and Mg were slightly decreased with increased NH4+ concentration. The NH4+ uptake system, which is saturated at less than 1mM NH4+, is able to regulate uptake of NH4+ at concentrations as high as 10 mM.

  8. Kinetics of concentration decay of specific organic matter in UASB reactors operating with and without return of aerobic sludge.

    Science.gov (United States)

    Pontes, P P; Chernicharo, C A L; Von Sperling, M

    2014-08-01

    This study aimed at assessing the influence of the return of excess aerobic sludge from a trickling filter (TF) upon the anaerobic digestion process in an upflow anaerobic sludge blanket (UASB) reactor, by evaluating its effect on the kinetics of the decay of specific organic matter (carbohydrates, proteins and lipids), as well as on the concentrations of volatile fatty acids in the UASB reactor. A pilot-scale UASB/TF system was used to perform the experiments, operating with (phase 2) and without (phase 1) excess sludge return from the TF to the UASB reactor. Sampling was carried out at different heights of the UASB reactor (0, 25, 125 and 225-cm height), and profile concentrations were determined for the following parameters: carbohydrates, proteins, lipids and volatile fatty acids. First-order kinetics showed the best fit to the decay of concentrations of carbohydrates, proteins, lipids and chemical oxygen demand (COD) in the UASB reactor. The parameters showing the best fit to the first-order kinetics were proteins and COD, during the sludge return phase. The occurrence of higher apparent reaction constants was further observed during the sludge return phase. For an influent COD concentration of 600 mg L-1 and hydraulic retention times of 2.1, 2.6 and 3.0 h in phase 1, the effluent COD concentrations were 125.3, 88.4 and 62.4 mg L-1, respectively, whereas in phase 2, the effluent COD concentrations were 75.5, 47.6 and 30.1 mg L-1, respectively.

  9. Apportionment of the sources of high fine particulate matter concentration events in a developing aerotropolis in Taoyuan, Taiwan.

    Science.gov (United States)

    Chuang, Ming-Tung; Chen, Yu-Chieh; Lee, Chung-Te; Cheng, Chung-Hao; Tsai, Yu-Jen; Chang, Shih-Yu; Su, Zhen-Sen

    2016-07-01

    To investigate the characteristics and contributions of the sources of fine particulate matter with a size of up to 2.5 μm (PM2.5) during the period when pollution events could easily occur in Taoyuan aerotropolis, Taiwan, this study conducted sampling at three-day intervals from September 2014 to January 2015. Based on the mass concentration of PM2.5, the sampling days were classified into high PM2.5 concentration event days (PM2.5>35 μg m(-3)) and non-event days (PM2.5<35 μg m(-3)). In addition, the chemical species, including water-soluble inorganic ions, carbonaceous components, and metal elements, were analyzed. The sources of pollution and their contributions were estimated using the positive matrix factorization (PMF) model. Furthermore, the effect of the weather type on the measurement results was also explored based on wind field conditions. The mass fractions of Cl(-) and NO3(-) increased when a high PM2.5 concentration event occurred, and they were also higher under local emitted conditions than under long range transported conditions, indicating that secondary nitrate aerosols were the major increasing local species that caused high PM2.5 concentration events. Seven sources of pollution could be distinguished using the PMF model on the basis of the characteristics of the species. Industrial emissions, coal combustion/urban waste incineration, and local emissions from diesel/gasoline vehicles were the main sources that contributed to pollution on high PM2.5 concentration event days. In order to reduction of high PM2.5 concentration events, the control of diesel and gasoline vehicle emission is important and should be given priority. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Quantification of urinary AICAR concentrations as a matter of doping controls.

    Science.gov (United States)

    Thomas, Andreas; Beuck, Simon; Eickhoff, Jens Christian; Guddat, Sven; Krug, Oliver; Kamber, Matthias; Schänzer, Wilhelm; Thevis, Mario

    2010-04-01

    Influencing the endurance in elite sports is one of the key points in modern sports science. Recently, a new class of prohibited substances reached in the focus of doping control laboratories and their misuse was classified as gene doping. The adenosine monophosphate activated protein kinase activator 5-amino-4-imidazolecarboxyamide ribonucleoside (AICAR) was found to significantly enhance the endurance even in sedentary mice after treatment. Due to endogenous production of AICAR in healthy humans, considerable amounts were present in the circulation and, thus, were excreted into urine. Considering these facts, the present study was initiated to fix reference values of renally cleared AICAR in elite athletes. Therefore a quantitative analytical method by means of isotope-dilution liquid chromatography (analytical column: C6-phenyl) coupled to tandem mass spectrometry, after a sample preparation consisting of a gentle dilution of native urine, was developed. Doping control samples of 499 athletes were analysed, and AICAR concentrations in urine were determined. The mean AICAR value for all samples was 2,186 ng/mL with a standard deviation of 1,655 ng/mL. Concentrations were found to differ depending on gender, type of sport and type of sample collection (in competition/out of competition). The method was fully validated for quantitative purposes considering the parameters linearity, inter- (12%, 7% and 10%) and intraday precision (14%, 9% and 12%) at low, mid and high concentration, robustness, accuracy (approx. 100%), limit of quantification (100 ng/mL), stability and ion suppression effects, employing an in-house synthesised (13)C(5)-labelled AICAR as internal standard.

  11. Response of winter fine particulate matter concentrations to emission and meteorology changes in North China

    Directory of Open Access Journals (Sweden)

    M. Gao

    2016-09-01

    Full Text Available The winter haze is a growing problem in North China, but the causes are not well understood. The chemistry version of the Weather Research and Forecasting model (WRF-Chem was applied in North China to examine how PM2.5 concentrations change in response to changes in emissions (sulfur dioxide (SO2, black carbon (BC, organic carbon (OC, ammonia (NH3, and nitrogen oxides (NOx, as well as meteorology (temperature, relative humidity (RH, and wind speeds changes in winter. From 1960 to 2010, the dramatic changes in emissions lead to +260 % increases in sulfate, +320 % increases in nitrate, +300 % increases in ammonium, +160 % increases in BC, and +50 % increases in OC. The responses of PM2.5 to individual emission species indicate that the simultaneous increases in SO2, NH3, and NOx emissions dominated the increases in PM2.5 concentrations. PM2.5 shows more notable increases in response to changes in SO2 and NH3 as compared to increases in response to changes in NOx emissions. In addition, OC also accounts for a large fraction in PM2.5 changes. These results provide some implications for haze pollution control. The responses of PM2.5 concentrations to temperature increases are dominated by changes in wind fields and mixing heights. PM2.5 shows relatively smaller changes in response to temperature increases and RH decreases compared to changes in response to changes in wind speed and aerosol feedbacks. From 1960 to 2010, aerosol feedbacks have been significantly enhanced due to higher aerosol loadings. The discussions in this study indicate that dramatic changes in emissions are the main cause of increasing haze events in North China, and long-term trends in atmospheric circulations may be another important cause since PM2.5 is shown to be substantially affected by wind speed and aerosol feedbacks. More studies are necessary to get a better understanding of the aerosol–circulation interactions.

  12. Trace elements in particulate matter from metropolitan regions of Northern China: Sources, concentrations and size distributions.

    Science.gov (United States)

    Pan, Yuepeng; Tian, Shili; Li, Xingru; Sun, Ying; Li, Yi; Wentworth, Gregory R; Wang, Yuesi

    2015-12-15

    Public concerns over airborne trace elements (TEs) in metropolitan areas are increasing, but long-term and multi-site observations of size-resolved aerosol TEs in China are still lacking. Here, we identify highly elevated levels of atmospheric TEs in megacities and industrial sites in a Beijing-Tianjin-Hebei urban agglomeration relative to background areas, with the annual mean values of As, Pb, Ni, Cd and Mn exceeding the acceptable limits of the World Health Organization. Despite the spatial variability in concentrations, the size distribution pattern of each trace element was quite similar across the region. Crustal elements of Al and Fe were mainly found in coarse particles (2.1-9 μm), whereas the main fraction of toxic metals, such as Cu, Zn, As, Se, Cd and Pb, was found in submicron particles (metals were enriched by over 100-fold relative to the Earth's crust. The size distributions of Na, Mg, K, Ca, V, Cr, Mn, Ni, Mo and Ba were bimodal, with two peaks at 0.43-0.65 μm and 4.7-5.8 μm. The combination of the size distribution information, principal component analysis and air mass back trajectory model offered a robust technique for distinguishing the main sources for airborne TEs, e.g., soil dust, fossil fuel combustion and industrial emissions, at different sites. In addition, higher elemental concentrations coincided with westerly flow, indicating that polluted soil and fugitive dust were major sources of TEs on the regional scale. However, the contribution of coal burning, iron industry/oil combustion and non-ferrous smelters to atmospheric metal pollution in Northern China should be given more attention. Considering that the concentrations of heavy metals associated with fine particles in the target region were significantly higher than those in other Asian sites, the implementations of strict environmental standards in China are required to reduce the amounts of these hazardous pollutants released into the atmosphere. Copyright © 2015 Elsevier B

  13. Prediction of daily fine particulate matter concentrations using aerosol optical depth retrievals from the Geostationary Operational Environmental Satellite (GOES).

    Science.gov (United States)

    Chudnovsky, Alexandra A; Lee, Hyung Joo; Kostinski, Alex; Kotlov, Tanya; Koutrakis, Petros

    2012-09-01

    Although ground-level PM2.5 (particulate matter with aerodynamic diameter < 2.5 microm) monitoring sites provide accurate measurements, their spatial coverage within a given region is limited and thus often insufficient for exposure and epidemiological studies. Satellite data expand spatial coverage, enhancing our ability to estimate location- and/or subject-specific exposures to PM2.5. In this study, the authors apply a mixed-effects model approach to aerosol optical depth (AOD) retrievals from the Geostationary Operational Environmental Satellite (GOES) to predict PM2.5 concentrations within the New England area of the United States. With this approach, it is possible to control for the inherent day-to-day variability in the AOD-PM2.5 relationship, which depends on time-varying parameters such as particle optical properties, vertical and diurnal concentration profiles, and ground surface reflectance. The model-predicted PM2.5 mass concentration are highly correlated with the actual observations, R2 = 0.92. Therefore, adjustment for the daily variability in AOD-PM2.5 relationship allows obtaining spatially resolved PM2.5 concentration data that can be of great value to future exposure assessment and epidemiological studies. The authors demonstrated how AOD can be used reliably to predict daily PM2.5 mass concentrations, providing determination of their spatial and temporal variability. Promising results are found by adjusting for daily variability in the AOD-PM2.5 relationship, without the need to account for a wide variety of individual additional parameters. This approach is of a great potential to investigate the associations between subject-specific exposures to PM2.5 and their health effects. Higher 4 x 4-km resolution GOES AOD retrievals comparing with the conventional MODerate resolution Imaging Spectroradiometer (MODIS) 10-km product has the potential to capture PM2.5 variability within the urban domain.

  14. Simultaneous removal of organic matter and salt ions from coal gasification wastewater RO concentrate and microorganisms succession in a MBR.

    Science.gov (United States)

    Jia, Shengyong; Han, Yuxing; Zhuang, Haifeng; Han, Hongjun; Li, Kun

    2017-10-01

    A lab-scale membrane bioreactor (MBR) with intermittent aeration was operated to treat the reverse osmosis concentrate derived from coal gasification wastewater. Results showed intermittent aeration represented slight effect on organic matter reduction but significant effect on nitrite and nitrate reduction, with 6h aeration and 6h non-aeration, removal efficiencies of organic matter, chloride, sulfate, nitrite and nitrate reached 48.35%, 40.91%, 34.28%, -36.05% and 64.34%, respectively. High-throughput sequencing showed a microorganisms succession from inoculated activated sludge (S1) to activated sludge in MBR (S2) with high salinity. Richness and diversity of microorganisms in S2 was lower than S1 and the community structure of S1 exhibited more even than S2. The most relative abundance of genus in S1 and S2 were unclassified_Desulfarculaceae (9.39%) and Roseibaca (62.1%), respectively. High salinity and intermittent aeration represented different influence on the denitrifying genus, and non-aeration phase provided feasible dissolved oxygen condition for denitrifying genera realizing denitrification. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Estimation of atmospheric columnar organic matter (OM) mass concentration from remote sensing measurements of aerosol spectral refractive indices

    Science.gov (United States)

    Zhang, Ying; Li, Zhengqiang; Sun, Yele; Lv, Yang; Xie, Yisong

    2018-04-01

    Aerosols have adverse effects on human health and air quality, changing Earth's energy balance and lead to climate change. The components of aerosol are important because of the different spectral characteristics. Based on the low hygroscopic and high scattering properties of organic matter (OM) in fine modal atmospheric aerosols, we develop an inversion algorithm using remote sensing to obtain aerosol components including black carbon (BC), organic matter (OM), ammonium nitrate-like (AN), dust-like (DU) components and aerosol water content (AW). In the algorithm, the microphysical characteristics (i.e. volume distribution and complex refractive index) of particulates are preliminarily separated to fine and coarse modes, and then aerosol components are retrieved using bimodal parameters. We execute the algorithm using remote sensing measurements of sun-sky radiometer at AERONET site (Beijing RADI) in a period from October of 2014 to January of 2015. The results show a reasonable distribution of aerosol components and a good fit for spectral feature calculations. The mean OM mass concentration in atmospheric column is account for 14.93% of the total and 56.34% of dry and fine-mode aerosol, being a fairly good correlation (R = 0.56) with the in situ observations near the surface layer.

  16. Nanofiltration and Tight Ultrafiltration Membranes for Natural Organic Matter Removal-Contribution of Fouling and Concentration Polarization to Filtration Resistance.

    Science.gov (United States)

    Winter, Joerg; Barbeau, Benoit; Bérubé, Pierre

    2017-07-02

    Nanofiltration (NF) and tight ultrafiltration (tight UF) membranes are a viable treatment option for high quality drinking water production from sources with high concentrations of contaminants. To date, there is limited knowledge regarding the contribution of concentration polarization (CP) and fouling to the increase in resistance during filtration of natural organic matter (NOM) with NF and tight UF. Filtration tests were conducted with NF and tight UF membranes with molecular weight cut offs (MWCOs) of 300, 2000 and 8000 Da, and model raw waters containing different constituents of NOM. When filtering model raw waters containing high concentrations of polysaccharides (i.e., higher molecular weight NOM), the increase in resistance was dominated by fouling. When filtering model raw waters containing humic substances (i.e., lower molecular weight NOM), the increase in filtration resistance was dominated by CP. The results indicate that low MWCO membranes are better suited for NOM removal, because most of the NOM in surface waters consist mainly of humic substances, which were only effectively rejected by the lower MWCO membranes. However, when humic substances are effectively rejected, CP can become extensive, leading to a significant increase in filtration resistance by the formation of a cake/gel layer at the membrane surface. For this reason, cross-flow operation, which reduces CP, is recommended.

  17. Comparison of remote sensing algorithms for retrieval of suspended particulate matter concentration from reflectance in coastal waters

    Science.gov (United States)

    Freeman, Lauren A.; Ackleson, Steven G.; Rhea, William Joseph

    2017-10-01

    Suspended particulate matter (SPM) is a key environmental indicator for rivers, estuaries, and coastal waters, which can be calculated from remote sensing reflectance obtained by an airborne or satellite imager. Here, algorithms from prior studies are applied to a dataset of in-situ at surface hyperspectral remote sensing reflectance, collected in three geographic regions representing different water types. These data show the optically inherent exponential nature of the relationship between reflectance and sediment concentration. However, linear models are also shown to provide a reasonable estimate of sediment concentration when utilized with care in similar conditions to those under which the algorithms were developed, particularly at lower SPM values (0 to 20 mg/L). Fifteen published SPM algorithms are tested, returning strong correlations of R2>0.7, and in most cases, R2>0.8. Very low SPM values show weaker correlation with algorithm calculated SPM that is not wavelength dependent. None of the tested algorithms performs well for high SPM values (>30 mg/L), with most algorithms underestimating SPM. A shift toward a smaller number of simple exponential or linear models relating satellite remote sensing reflectance to suspended sediment concentration with regional consideration will greatly aid larger spatiotemporal studies of suspended sediment trends.

  18. Nanofiltration and Tight Ultrafiltration Membranes for Natural Organic Matter Removal—Contribution of Fouling and Concentration Polarization to Filtration Resistance

    Directory of Open Access Journals (Sweden)

    Joerg Winter

    2017-07-01

    Full Text Available Nanofiltration (NF and tight ultrafiltration (tight UF membranes are a viable treatment option for high quality drinking water production from sources with high concentrations of contaminants. To date, there is limited knowledge regarding the contribution of concentration polarization (CP and fouling to the increase in resistance during filtration of natural organic matter (NOM with NF and tight UF. Filtration tests were conducted with NF and tight UF membranes with molecular weight cut offs (MWCOs of 300, 2000 and 8000 Da, and model raw waters containing different constituents of NOM. When filtering model raw waters containing high concentrations of polysaccharides (i.e., higher molecular weight NOM, the increase in resistance was dominated by fouling. When filtering model raw waters containing humic substances (i.e., lower molecular weight NOM, the increase in filtration resistance was dominated by CP. The results indicate that low MWCO membranes are better suited for NOM removal, because most of the NOM in surface waters consist mainly of humic substances, which were only effectively rejected by the lower MWCO membranes. However, when humic substances are effectively rejected, CP can become extensive, leading to a significant increase in filtration resistance by the formation of a cake/gel layer at the membrane surface. For this reason, cross-flow operation, which reduces CP, is recommended.

  19. Black Carbon and Particulate Matter (PM2.5) Concentrations in New York City’s Subway Stations

    Science.gov (United States)

    2015-01-01

    The New York City (NYC) subway is the main mode of transport for over 5 million passengers on an average weekday. Therefore, airborne pollutants in the subway stations could have a significant impact on commuters and subway workers. This study looked at black carbon (BC) and particulate matter (PM2.5) concentrations in selected subway stations in Manhattan. BC and PM2.5 levels were measured in real time using a Micro-Aethalometer and a PDR-1500 DataRAM, respectively. Simultaneous samples were also collected on quartz filters for organic and elemental carbon (OC/EC) analysis and on Teflon filters for gravimetric and trace element analysis. In the underground subway stations, mean real time BC concentrations ranged from 5 to 23 μg/m3, with 1 min average peaks >100 μg/m3, while real time PM2.5 levels ranged from 35 to 200 μg/m3. Mean EC levels ranged from 9 to 12.5 μg/m3. At street level on the same days, the mean BC and PM2.5 concentrations were below 3 and 10 μg/m3, respectively. This study shows that both BC soot and PM levels in NYC’s subways are considerably higher than ambient urban street levels and that further monitoring and investigation of BC and PM subway exposures are warranted. PMID:25409007

  20. Response of fine particulate matter concentrations to changes of emissions and temperature in Europe

    Directory of Open Access Journals (Sweden)

    A. G. Megaritis

    2013-03-01

    Full Text Available PMCAMx-2008, a three dimensional chemical transport model (CTM, was applied in Europe to quantify the changes in fine particle (PM2.5 concentration in response to different emission reductions as well as to temperature increase. A summer and a winter simulation period were used, to investigate the seasonal dependence of the PM2.5 response to 50% reductions of sulfur dioxide (SO2, ammonia (NH3, nitrogen oxides (NOx, anthropogenic volatile organic compounds (VOCs and anthropogenic primary organic aerosol (POA emissions and also to temperature increases of 2.5 and 5 K. Reduction of NH3 emissions seems to be the most effective control strategy for reducing PM2.5, in both periods, resulting in a decrease of PM2.5 up to 5.1 μg m−3 and 1.8 μg m−3 (5.5% and 4% on average during summer and winter respectively, mainly due to reduction of ammonium nitrate (NH4NO3 (20% on average in both periods. The reduction of SO2 emissions decreases PM2.5 in both periods having a significant effect over the Balkans (up to 1.6 μg m−3 during the modeled summer period, mainly due to decrease of sulfate (34% on average over the Balkans. The anthropogenic POA control strategy reduces total OA by 15% during the modeled winter period and 8% in the summer period. The reduction of total OA is higher in urban areas close to its emissions sources. A slight decrease of OA (8% in the modeled summer period and 4% in the modeled winter period is also predicted after a 50% reduction of VOCs emissions due to the decrease of anthropogenic SOA. The reduction of NOx emissions reduces PM2.5 (up to 3.4 μg m−3 during the summer period, due to a decrease of NH4NO3, causing although an increase of ozone concentration in major urban areas and over Western Europe. Additionally, the NOx control strategy actually increases PM2.5 levels during the winter period, due to more oxidants becoming available to react with SO2 and VOCs. The increase of temperature results in a decrease of PM2

  1. Application of digital image processing to a β-gauge for determining mass concentration of suspending particulate matter in atmosphere

    International Nuclear Information System (INIS)

    Gotoh, Takao

    1992-01-01

    A two-dimensional image of the mass concentration of suspending particulate matter (SPM) collected on Millipore filter paper was photographed with Ultrofilm- 3 H. The printed paper image was transformed into a digital image (256 x 256 pixels) with 256 gray levels. Two results were obtained. The averaged values of gray level over all pixels of the digital image was found to correlate with the mass value measured by a β-gauge. The characteristic range of the digital image which was transformed to frequency by two-dimensional fast fourier transformation was found in the low frequency. It was presumed to relate to SPM from anthropogenic sources because the SPMs usually show higher density and smaller particle size than SPMs from natural sources. (author)

  2. Concentrations of trace elements and compounds in the airborne suspended particulate matter in Cleveland, Ohio, from August 1971 to August 1972 and their dependence on wind direction: Complete data listing and concentration roses

    Science.gov (United States)

    King, R. B.; Neustadter, H. E.

    1976-01-01

    Concentrations of 75 chemical constituents in the airborne particulate matter were measured in Cleveland, Ohio during 1971 and 1972. Daily values, maxima, geometric means and their standard deviations covering a 1-year period (45 to 50 sampling days) at each of 16 sites are presented on microfiche for 60 elements, and for a lesser number of days for 10 polycyclic aromatic hydrocarbon compounds (PAH), the aliphatic hydrocarbon compounds (AH) as a group and carbon. In addition, concentration roses showing directional properties are presented for 39 elements, 10 PAH and the AH as a group. The elements (except carbon) are shown both in terms of concentration and percentage of the suspended particulate matter.

  3. An exploratory analysis of the relationship between ambient ozone and particulate matter concentrations during early pregnancy and selected birth defects in Texas

    Science.gov (United States)

    Background: Associations between ozone (O3) and fine particulate matter (PM2.5) concentrations and birth outcomes have been previously demonstrated. We perform an exploratory analysis of O3 and PM2.5 concentrations during early pregnancy and multiple types of birth defects. Met...

  4. Amino acid profile of metabolisable protein in lactating dairy cows is affected by dry matter concentration in grass-clover silage

    DEFF Research Database (Denmark)

    Johansen, Marianne; Lund, Peter; Weisbjerg, Martin Riis

    2018-01-01

    Our previous study showed that supply of metabolisable protein (MP) to lactating dairy cows increased with increasing dry matter (DM) concentration in grass-clover silage. The aim of this study was to examine how amino acid (AA) profile of MP was affected by silage DM concentration. Eight grass-c...

  5. Cretaceous – Paleogene boundary Fish Clay at Højerup (Stevns Klint, Denmark: Zn, Pb and REE in kerogen

    Directory of Open Access Journals (Sweden)

    MILOS G. DJORDJEVIC

    2008-04-01

    Full Text Available Geochemical analyses of Zn, Pb and rare earth elements (La, Ce, Nd, Sm, Eu, Tb, Yb and Lu in the kerogen of the black marl at the Cretaceous – Paleogene boundary Fish Clay at Højerup were performed. Substantial proportions of the Zn, Pb and rare earths were probably contained in terrestrial humic substances (the kerogen precursor arriving at the marine sedimentary site. This is in accord with a previous hypothesis that kerogen is mainly derived from humic acids of an oxic soil in of the adjacent coastal areas of eastern Denmark. It is also suggested that humics enriched in Zn, Pb and rare earth elements were transported mainly through fluvial transport into the deposition site of the Fish Clay. Local weathering/leaching of the impact–eject fallout on the land surface and local terrestrial rocks by impact-induced? acid surface waters perhaps played an important role in providing Zn, Pb and rare earths to these humic substances. Apparently, chondritic and non-chondritic Zn originated from the impact fallout; Pb and rare earth elements were most likely sourced by exposed rocks in the coastal areas of eastern Denmark.

  6. Construction of Multi-Year Time-Series Profiles of Suspended Particulate Inorganic Matter Concentrations Using Machine Learning Approach

    Directory of Open Access Journals (Sweden)

    Pannimpullath R. Renosh

    2017-12-01

    Full Text Available Hydro-sedimentary numerical models have been widely employed to derive suspended particulate matter (SPM concentrations in coastal and estuarine waters. These hydro-sedimentary models are computationally and technically expensive in nature. Here we have used a computationally less-expensive, well-established methodology of self-organizing maps (SOMs along with a hidden Markov model (HMM to derive profiles of suspended particulate inorganic matter (SPIM. The concept of the proposed work is to benefit from all available data sets through the use of fusion methods and machine learning approaches that are able to process a growing amount of available data. This approach is applied to two different data sets entitled “Hidden” and “Observable”. The hidden data are composed of 15 months (27 September 2007 to 30 December 2008 of hourly SPIM profiles extracted from the Regional Ocean Modeling System (ROMS. The observable data include forcing parameter variables such as significant wave heights ( H s and H s 50 (50 days from the Wavewatch 3-HOMERE database and barotropic currents ( U b a r and V b a r from the Iberian–Biscay–Irish (IBI reanalysis data. These observable data integrate hourly surface samples from 1 February 2002 to 31 December 2012. The time-series profiles of the SPIM have been derived from four different stations in the English Channel by considering 15 months of output hidden data from the ROMS as a statistical representation of the ocean for ≈11 years. The derived SPIM profiles clearly show seasonal and tidal fluctuations in accordance with the parent numerical model output. The surface SPIM concentrations of the derived model have been validated with satellite remote sensing data. The time series of the modeled SPIM and satellite-derived SPIM show similar seasonal fluctuations. The ranges of concentrations for the four stations are also in good agreement with the corresponding satellite data. The high accuracy of the

  7. Airborne Particulate Matter in Two Multi-Family Green Buildings: Concentrations and Effect of Ventilation and Occupant Behavior.

    Science.gov (United States)

    Patton, Allison P; Calderon, Leonardo; Xiong, Youyou; Wang, Zuocheng; Senick, Jennifer; Sorensen Allacci, MaryAnn; Plotnik, Deborah; Wener, Richard; Andrews, Clinton J; Krogmann, Uta; Mainelis, Gediminas

    2016-01-20

    There are limited data on air quality parameters, including airborne particulate matter (PM) in residential green buildings, which are increasing in prevalence. Exposure to PM is associated with cardiovascular and pulmonary diseases, and since Americans spend almost 90% of their time indoors, residential exposures may substantially contribute to overall airborne PM exposure. Our objectives were to: (1) measure various PM fractions longitudinally in apartments in multi-family green buildings with natural (Building E) and mechanical (Building L) ventilation; (2) compare indoor and outdoor PM mass concentrations and their ratios (I/O) in these buildings, taking into account the effects of occupant behavior; and (3) evaluate the effect of green building designs and operations on indoor PM. We evaluated effects of ventilation, occupant behaviors, and overall building design on PM mass concentrations and I/O. Median PMTOTAL was higher in Building E (56 µg/m³) than in Building L (37 µg/m³); I/O was higher in Building E (1.3-2.0) than in Building L (0.5-0.8) for all particle size fractions. Our data show that the building design and occupant behaviors that either produce or dilute indoor PM (e.g., ventilation systems, combustion sources, and window operation) are important factors affecting residents' exposure to PM in residential green buildings.

  8. Airborne Particulate Matter in Two Multi-Family Green Buildings: Concentrations and Effect of Ventilation and Occupant Behavior

    Directory of Open Access Journals (Sweden)

    Allison P. Patton

    2016-01-01

    Full Text Available There are limited data on air quality parameters, including airborne particulate matter (PM in residential green buildings, which are increasing in prevalence. Exposure to PM is associated with cardiovascular and pulmonary diseases, and since Americans spend almost 90% of their time indoors, residential exposures may substantially contribute to overall airborne PM exposure. Our objectives were to: (1 measure various PM fractions longitudinally in apartments in multi-family green buildings with natural (Building E and mechanical (Building L ventilation; (2 compare indoor and outdoor PM mass concentrations and their ratios (I/O in these buildings, taking into account the effects of occupant behavior; and (3 evaluate the effect of green building designs and operations on indoor PM. We evaluated effects of ventilation, occupant behaviors, and overall building design on PM mass concentrations and I/O. Median PMTOTAL was higher in Building E (56 µg/m3 than in Building L (37 µg/m3; I/O was higher in Building E (1.3–2.0 than in Building L (0.5–0.8 for all particle size fractions. Our data show that the building design and occupant behaviors that either produce or dilute indoor PM (e.g., ventilation systems, combustion sources, and window operation are important factors affecting residents’ exposure to PM in residential green buildings.

  9. Biological phosphorus and nitrogen removal in sequencing batch reactors: effects of cycle length, dissolved oxygen concentration and influent particulate matter.

    Science.gov (United States)

    Ginige, Maneesha P; Kayaalp, Ahmet S; Cheng, Ka Yu; Wylie, Jason; Kaksonen, Anna H

    2013-01-01

    Removal of phosphorus (P) and nitrogen (N) from municipal wastewaters is required to mitigate eutrophication of receiving water bodies. While most treatment plants achieve good N removal using influent carbon (C), the use of influent C to facilitate enhanced biological phosphorus removal (EBPR) is poorly explored. A number of operational parameters can facilitate optimum use of influent C and this study investigated the effects of cycle length, dissolved oxygen (DO) concentration during aerobic period and influent solids on biological P and N removal in sequencing batch reactors (SRBs) using municipal wastewaters. Increasing cycle length from 3 to 6 h increased P removal efficiency, which was attributed to larger portion of N being removed via nitrite pathway and more biodegradable organic C becoming available for EBPR. Further increasing cycle length from 6 to 8 h decreased P removal efficiencies as the demand for biodegradable organic C for denitrification increased as a result of complete nitrification. Decreasing DO concentration in the aerobic period from 2 to 0.8 mg L(-1) increased P removal efficiency but decreased nitrification rates possibly due to oxygen limitation. Further, sedimented wastewater was proved to be a better influent stream than non-sedimented wastewater possibility due to the detrimental effect of particulate matter on biological nutrient removal.

  10. Mass concentration, composition and sources of fine and coarse particulate matter in Tijuana, Mexico, during Cal-Mex campaign

    Science.gov (United States)

    Minguillón, María Cruz; Campos, Arturo Alberto; Cárdenas, Beatriz; Blanco, Salvador; Molina, Luisa T.; Querol, Xavier

    2014-05-01

    This work was carried out in the framework of the Cal-Mex project, which focuses on investigating the atmosphere along Mexico-California border region. Sampling was carried out at two sites located in Tijuana urban area: Parque Morelos and Metales y Derivados. PM2.5 and PM10 24 h samples were collected every three days from 17th May 2010 to 27th June 2010, and were used for gravimetric and chemical analyses (major and minor elements, inorganic ions, organic and elemental carbon) of PM. A subsequent Positive Matrix Factorization (PMF) analysis was performed. PM2.5 and PM10 average concentrations during Cal-Mex were relatively lower compared to usual annual averages. Trace elements concentrations recorded in the present study were lower than those recorded in Mexico City in 2006, with the exception of Pb at Metales y Derivados, attributed to the influence of a specific industrial source, which also includes As, Cd and Tl. Apart from this industrial source, both urban sites were found to be affected by similar sources with respect to bulk PM. Fine PM (PM2.5) was mainly apportioned by fueloil and biomass combustion and secondary aerosols, and road traffic. Coarse PM (PM2.5-10) was mainly apportioned by a mineral source (sum of road dust resuspension, construction emissions and natural soil) and fresh and aged sea salt. The road traffic was responsible for more than 60% of the fine elemental carbon and almost 40% of the fine organic matter.

  11. Seasonal and nonseasonal variability of satellite-derived chlorophyll and colored dissolved organic matter concentration in the California Current

    Science.gov (United States)

    Kahru, Mati; Mitchell, B. Greg

    2001-02-01

    Time series of surface chlorophyll a concentration (Chl) and colored dissolved organic matter (CDOM) derived from the Ocean Color and Temperature Sensor and Sea-Viewing Wide Field-of-View Sensor were evaluated for the California Current area using regional algorithms. Satellite data composited for 8-day periods provide the ability to describe large-scale changes in surface parameters. These changes are difficult to detect based on in situ observations alone that suffer from undersampling the large temporal and spatial variability, especially in Chl. We detected no significant bias in satellite Chl estimates compared with ship-based measurements. The variability in CDOM concentration was significantly smaller than that in Chl, both spatially and temporally. While being subject to large interannual and short-term variations, offshore waters (100-1000 km from the shore) have an annual cycle of Chl and CDOM with a maximum in winter-spring (December-March) and a minimum in late summer. For inshore waters the maximum is more likely in spring (April-May). We detect significant increase in both Chl and CDOM off central and southern California during the La Niña year of 1999. The trend of increasing Chl and CDOM from October 1996 to June 2000 is statistically significant in many areas.

  12. Apportionment of the sources of high fine particulate matter concentration events in a developing aerotropolis in Taoyuan, Taiwan

    International Nuclear Information System (INIS)

    Chuang, Ming-Tung; Chen, Yu-Chieh; Lee, Chung-Te; Cheng, Chung-Hao; Tsai, Yu-Jen; Chang, Shih-Yu; Su, Zhen-Sen

    2016-01-01

    To investigate the characteristics and contributions of the sources of fine particulate matter with a size of up to 2.5 μm (PM 2.5 ) during the period when pollution events could easily occur in Taoyuan aerotropolis, Taiwan, this study conducted sampling at three-day intervals from September 2014 to January 2015. Based on the mass concentration of PM 2.5 , the sampling days were classified into high PM 2.5 concentration event days (PM 2.5 >35 μg m −3 ) and non-event days (PM 2.5 <35 μg m −3 ). In addition, the chemical species, including water-soluble inorganic ions, carbonaceous components, and metal elements, were analyzed. The sources of pollution and their contributions were estimated using the positive matrix factorization (PMF) model. Furthermore, the effect of the weather type on the measurement results was also explored based on wind field conditions. The mass fractions of Cl − and NO 3 − increased when a high PM 2.5 concentration event occurred, and they were also higher under local emitted conditions than under long range transported conditions, indicating that secondary nitrate aerosols were the major increasing local species that caused high PM 2.5 concentration events. Seven sources of pollution could be distinguished using the PMF model on the basis of the characteristics of the species. Industrial emissions, coal combustion/urban waste incineration, and local emissions from diesel/gasoline vehicles were the main sources that contributed to pollution on high PM 2.5 concentration event days. In order to reduction of high PM 2.5 concentration events, the control of diesel and gasoline vehicle emission is important and should be given priority. - Highlights: • The mass fractions of NH 4 + , K + , Cl − and NO 3 − increased during PM 2.5 event days. • Reduction of coal combustion/urban waste incineration emissions should be prioritized. • The control of vehicle emission is important in the locally emitted periods. • Secondary

  13. Black carbon concentrations in California vehicles and estimation of in-vehicle diesel exhaust particulate matter exposures

    Science.gov (United States)

    Fruin, Scott A.; Winer, Arthur M.; Rodes, Charles E.

    This research assessed in-vehicle exposures to black carbon (BC) as an indicator of diesel particulate matter (DPM) exposures. Approximately 50 h of real-time Aethalometer BC measurements were made inside vehicles driven on freeway and arterial loops in Los Angeles and Sacramento. Video tapes of the driver's view were transcribed to record the traffic conditions, vehicles followed, and vehicle occupant observations, and these results were tested for their associations with BC concentration. In-vehicle BC concentrations were highest when directly following diesel-powered vehicles, particularly those with low exhaust pipe locations. The lowest BC concentrations were observed while following gasoline-powered passenger cars, on average no different than not following any vehicle. Because diesel vehicles were over-sampled in the field study, results were not representative of real-world driving. To calculate representative exposures, in-vehicle BC concentrations were grouped by the type of vehicle followed, for each road type and congestion level. These groupings were then re-sampled stochastically, in proportion to the fraction of statewide vehicle miles traveled (VMT) under each of those conditions. The approximately 6% of time spent following diesel vehicles led to 23% of the in-vehicle BC exposure, while the remaining exposure was due to elevated roadway BC concentrations. In-vehicle BC exposures averaged 6 μg m -3 in Los Angeles and the Bay Area, the regions with the highest congestion and the majority of the state's VMT. The statewide average in-vehicle BC exposure was 4 μg m -3, corresponding to DPM concentrations of 7-23 μg m -3, depending on the Aethalometer response to elemental carbon (EC) and the EC fraction of the DPM. In-vehicle contributions to overall DPM exposures ranged from approximately 30% to 55% of total DPM exposure on a statewide population basis. Thus, although time spent in vehicles was only 1.5 h day -1 on average, vehicles may be the most

  14. Effect of grinding intensity and pelleting of the diet on indoor particulate matter concentrations and growth performance of weanling pigs.

    Science.gov (United States)

    Ulens, T; Demeyer, P; Ampe, B; Van Langenhove, H; Millet, S

    2015-02-01

    This study evaluated the effect of feed form and grinding intensity of the pig diet and the interaction between both on the particulate matter (PM) concentrations inside a pig nursery and the growth performances of weanling pigs. Four diets were compared: finely ground meal, coarsely ground meal, finely ground pellets, and coarsely ground pellets. Four weaning rounds with 144 pigs per weaning round, divided over 4 identical compartments, were monitored. Within each weaning round, each compartment was randomly assigned to 1 of 4 treatments. A hammer mill with a screen of 1.5 or 6 mm was used to grind the ingredients of the finely ground and coarsely ground feeds, respectively. Indoor concentrations of the following PM fractions were measured: PM that passes through a size-selective inlet with a 50 % efficiency cutoff at 10 (PM10) , 2.5 (PM2.5), or 1 (PM1) μm aerodynamic diameter, respectively (USEPA, 2004). Feeding pelleted diets instead of meal diets gave rise to higher PM10 (P Grinding intensity had an effect only on PM10 (P grinding intensity was found for any of the PM fractions. Interactions (P grinding intensity on ADFI and ADG were found. Grinding intensity had an effect only on the meal diets with higher ADFI for the coarsely ground meal. Pigs fed the finely ground meal had a lower (P grinding intensity. Pelleting the feed gave rise to a higher G:F. In conclusion, a contradiction between environmental concerns and performance results was found. Feeding pelleted diets to the piglets improved growth performance but also increased indoor PM concentrations.

  15. Preliminary analysis of variability in concentration of fine particulate matter - PM1.0, PM2.5 and PM10 in area of Poznań city

    Directory of Open Access Journals (Sweden)

    Sówka Izabela

    2018-01-01

    Full Text Available It is commonly known, that suspended particulate matter pose a threat to human life and health, negatively influence the flora, climate and also materials. Especially dangerous is the presence of high concentration of particulate matter in the area of cities, where density of population is high. The research aimed at determining the variability of suspended particulate matter concentration (PM1.0, PM2.5 and PM10 in two different thermal seasons, in the area of Poznań city. As a part of carried out work we analyzed the variability of concentrations and also performed a preliminary analysis of their correlation. Measured concentrations of particulate matter were contained within following ranges: PM10 – 8.7-69.6 μg/m3, PM2.5 – 2.2-88.5 μg/m3, PM1.0 – 2.5-22.9 μg/m3 in the winter season and 1.0-42.8 μg/m3 (PM10, 1.2-40.3 μg/m3 (PM2.5 and 2.7-10.4 (PM1.0 in the summer season. Preliminary correlative analysis indicated interdependence between the temperature of air, the speed of wind and concentration of particulate matter in selected measurement points. The values of correlation coefficients between the air temperature, speed of wind and concentrations of particulate matter were respectively equal to: for PM10: -0.59 and -0.55 (Jana Pawła II Street, -0.53 and -0.53 (Szymanowskiego Street, for PM2.5: -0.60 and -0.53 (Jana Pawła II Street and for PM1.0 -0.40 and -0.59 (Jana Pawła II Street.

  16. In vivo magnetic resonance spectroscopy measurement of gray-matter and white-matter gamma-aminobutyric acid concentration in sensorimotor cortex using a motion-controlled MEGA point-resolved spectroscopy sequence.

    Science.gov (United States)

    Bhattacharyya, Pallab K; Phillips, Micheal D; Stone, Lael A; Lowe, Mark J

    2011-04-01

    Gamma-aminobutyric acid (GABA) is a major inhibitory neurotransmitter in the brain. Understanding the GABA concentration, in vivo, is important to understand normal brain function. Using MEGA point-resolved spectroscopy sequence with interleaved water scans to detect subject motion, GABA level of sensorimotor cortex was measured using a voxel identified from a functional magnetic resonance imaging scan. The GABA level in a 20×20×20-mm(3) voxel consisting of 37%±7% gray matter, 52%±12% white matter and 11%±8% cerebrospinal fluid in the sensorimotor region was measured to be 1.43±0.48 mM. In addition, using linear regression analysis, GABA concentrations within gray and white matter were calculated to be 2.87±0.61 and 0.33±0.11 mM, respectively. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Global Estimates of Average Ground-Level Fine Particulate Matter Concentrations from Satellite-Based Aerosol Optical Depth

    Science.gov (United States)

    Van Donkelaar, A.; Martin, R. V.; Brauer, M.; Kahn, R.; Levy, R.; Verduzco, C.; Villeneuve, P.

    2010-01-01

    Exposure to airborne particles can cause acute or chronic respiratory disease and can exacerbate heart disease, some cancers, and other conditions in susceptible populations. Ground stations that monitor fine particulate matter in the air (smaller than 2.5 microns, called PM2.5) are positioned primarily to observe severe pollution events in areas of high population density; coverage is very limited, even in developed countries, and is not well designed to capture long-term, lower-level exposure that is increasingly linked to chronic health effects. In many parts of the developing world, air quality observation is absent entirely. Instruments aboard NASA Earth Observing System satellites, such as the MODerate resolution Imaging Spectroradiometer (MODIS) and the Multi-angle Imaging SpectroRadiometer (MISR), monitor aerosols from space, providing once daily and about once-weekly coverage, respectively. However, these data are only rarely used for health applications, in part because the can retrieve the amount of aerosols only summed over the entire atmospheric column, rather than focusing just on the near-surface component, in the airspace humans actually breathe. In addition, air quality monitoring often includes detailed analysis of particle chemical composition, impossible from space. In this paper, near-surface aerosol concentrations are derived globally from the total-column aerosol amounts retrieved by MODIS and MISR. Here a computer aerosol simulation is used to determine how much of the satellite-retrieved total column aerosol amount is near the surface. The five-year average (2001-2006) global near-surface aerosol concentration shows that World Health Organization Air Quality standards are exceeded over parts of central and eastern Asia for nearly half the year.

  18. Indoor-outdoor concentrations of fine particulate matter in school building microenvironments near a mine tailing deposit

    Directory of Open Access Journals (Sweden)

    Leonardo Martínez

    2016-11-01

    Full Text Available Indoor air quality in school classrooms is a major pediatric health concern because children are highly susceptible to adverse effects from xenobiotic exposure. Fine particulate matter (PM2.5 emitted from mining waste deposits within and near cities in northern Chile is a serious environmental problem. We measured PM2.5 in school microenvironments in urban areas of Chañaral, a coastal community whose bay is contaminated with mine tailings. PM2.5 levels were measured in six indoor and outdoor school environments during the summer and winter of 2012 and 2013. Measurements were taken during school hours on two consecutive days. Indoor PM2.5 concentrations were 12.53–72.38 μg/m3 in the summer and 21.85–100.53 μg/m3 in winter, while outdoor concentrations were 11.86–181.73 μg/m3 in the summer and 21.50–93.07 μg/m3 in winter. Indoor/outdoor ratios were 0.17–2.76 in the summer and 0.64–4.49 in winter. PM2.5 levels were higher in indoor microenvironments during the winter, at times exceeding national and international recommendations. Our results demonstrate that indoor air quality Chañaral school microenvironments is closely associated with outdoor air pollution attributable to the nearby mine tailings. Policymakers should enact environmental management strategies to minimize further environmental damage and mitigate the risks that this pollution poses for pediatric health.

  19. Influence of dissolved organic matter concentration and composition on the removal efficiency of perfluoroalkyl substances (PFASs) during drinking water treatment.

    Science.gov (United States)

    Kothawala, Dolly N; Köhler, Stephan J; Östlund, Anna; Wiberg, Karin; Ahrens, Lutz

    2017-09-15

    Drinking water treatment plants (DWTPs) are constantly adapting to a host of emerging threats including the removal of micro-pollutants like perfluoroalkyl substances (PFASs), while concurrently considering how background levels of dissolved organic matter (DOM) influences their removal efficiency. Two adsorbents, namely anion exchange (AE) and granulated active carbon (GAC) have shown particular promise for PFAS removal, yet the influence of background levels of DOM remains poorly explored. Here we considered how the removal efficiency of 13 PFASs are influenced by two contrasting types of DOM at four concentrations, using both AE (Purolite A-600 ® ) and GAC (Filtrasorb 400 ® ). We placed emphasis on the pre-equilibrium conditions to gain better mechanistic insight into the dynamics between DOM, PFASs and adsorbents. We found AE to be very effective at removing both PFASs and DOM, while largely remaining resistant to even high levels of background DOM (8 mg carbon L -1 ) and surprisingly found that smaller PFASs were removed slightly more efficiently than longer chained counterparts, In contrast, PFAS removal efficiency with GAC was highly variable with PFAS chain length, often improving in the presence of DOM, but with variable response based on the type of DOM and PFAS chain length. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Gray matter concentration and effective connectivity changes in Alzheimer's disease: a longitudinal structural MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xingfeng; Coyle, Damien; Maguire, Liam; Watson, David R.; McGinnity, Thomas M. [University of Ulster, Intelligent Systems Research Centre, Magee Campus, Derry, Northern Ireland (United Kingdom)

    2011-10-15

    Understanding disease progression in Alzheimer's disease (AD) awaits the resolution of three fundamental questions: first, can we identify the location of ''seed'' regions where neuropathology is first present? Some studies have suggested the medial temporal lobe while others have suggested the hippocampus. Second, are there similar atrophy rates within affected regions in AD? Third, is there evidence of causality relationships between different affected regions in AD progression ?To address these questions, we conducted a longitudinal MRI study to investigate the gray matter (GM) changes in AD progression. Abnormal brain regions were localized by a standard voxel-based morphometry method, and the absolute atrophy rate in these regions was calculated using a robust regression method. Primary foci of atrophy were identified in the hippocampus and middle temporal gyrus (MTG). A model based upon the Granger causality approach was developed to investigate the cause-effect relationship over time between these regions based on GM concentration. Results show that in the earlier stages of AD, primary pathological foci are in the hippocampus and entorhinal cortex. Subsequently, atrophy appears to subsume the MTG. The causality results show that there is in fact little difference between AD and age-matched healthy control in terms of hippocampus atrophy, but there are larger differences in MTG, suggesting that local pathology in MTG is the predominant progressive abnormality during intermediate stages of AD development. (orig.)

  1. Monitoring the effects of disposal of fine sediments from maintenance dredging on suspended particulate matter concentration in the Belgian nearshore area

    OpenAIRE

    Fettweis, M.; Baeye, M.; Francken, F.; Lauwaert, B.; Van den Eynde, D.; Van Lancker, V.; Martens, C.; Michielsen, T.

    2012-01-01

    The impact of continuous disposal of fine-grained sediments from maintenance dredging works on the suspended particulate matter concentration in a shallow nearshore turbidity maximum was investigated during dredging experiment (port of Zeebrugge, southern North Sea). Before, during and after the experiment monitoring of SPM concentration using OBS and ADV altimetry was carried out at a location 5 km west of the disposal site. A statistical analysis, based on the concept of populations and sub...

  2. Monitoring the effects of disposal of fine sediments from maintenance dredging on suspended particulate matter concentration in the Belgian nearshore area (southern North Sea)

    OpenAIRE

    Fettweis, M.; Baeye, M.; Francken, F.; Lauwaert, B.; Van den Eynde, D.; Van Lancker, V.; Martens, C.; Michielsen, T.

    2011-01-01

    The impact of continuous disposal of fine-grained sediments from maintenance dredging works on the suspended particulate matter concentration in a shallow nearshore turbidity maximum was investigated during dredging experiment (port of Zeebrugge, southern North Sea). Before, during and after the experiment monitoring of SPM concentration using OBS and ADV altimetry was carried out at a location 5 km west of the disposal site. A statistical analysis, based on the concept of populations and sub...

  3. An integrated system for the determination of the local, regional and long-transport contributions to Particulate Matter concentrations

    Science.gov (United States)

    Amodio, M.; Andriani, E.; Daresta, B. E.; de Gennaro, G.; di Gilio, A.; Ielpo, P.,; Placentino, C. M.; Trizio, L.; Tutino, M.

    2010-05-01

    Several epidemiological studies have shown the negative effects of air pollution on human health, which range from respiratory and cardiovascular disease to neurotoxic effects, and cancer. Most recent investigations have been focused on health toxicological features of Particulate Matter (PM) and its interactions with other pollutants: it was found that fine particles (PM2.5) could be an effective media to transport these pollutants deeply into the lung and to cause many kind of reactions which include oxidative stress, local pulmonary and systemic inflammatory responses (Künzli and Perez, 2009). Based on these implications on public health, many countries have developed plans to suggest effective control strategies which involve the identification of Particulate Matter sources, the quantitative estimation of the emission rates of the pollutants, the understanding of PM transport, mixing and transformation processes and the identification of main factors influencing PM concentrations. In this field, receptor models can be useful tools to estimate sources contributions to PM collected in an area under investigations. Different approaches to receptor model analysis can be distinguished on basis of whether chemical characteristics of emission sources are required to be known before the source apportionment. The multivariate approach could be preferred when a lack of information concerning sources profiles occurred (Hopke, 2003). In this work, the results obtained by applying an integrated approach in the monitoring of PM using several typologies of instrumentations will be shown. A prototype for the determination of the contributions of a single source (‘fugitive emission') on the fine PM concentrations has been developed: it consists of a Swam dual-channel sampler, an OPC Monitor, a sonic anemometer and a PBL Mixing monitor. The investigated site chosen for the application of prototype will be the iron and steel pole of Taranto (Apulia Region, South of Italy

  4. Effect of photodegradation and biodegradation on the concentration and composition of dissolved organic matter in diverse waterbodies

    Science.gov (United States)

    Manalilkada Sasidharan, S.; Dash, P.; Singh, S.; Lu, Y.

    2017-12-01

    The objective of this research was to quantify the effects of photodegradation and biodegradation on the dissolved organic matter (DOM) concentration and composition in five distinct waterbodies with diverse types of watershed land use and land cover in the southeastern United States. The water bodies included an agricultural pond, a lake in a predominantly forested watershed, a man-made reservoir, an estuary, and a bay. Two sets of samples were prepared from these water bodies by dispensing filtered water samples to unfiltered samples in 10:1 ratio. The first set was kept in the sunlight during the day (12 hours), and colored dissolved organic matter (CDOM) absorption and fluorescence were measured periodically over a 30-day period for examining the effects of combined photo- and biodegradation. The second set of samples was kept in the dark for examining the effects of biodegradation alone, and CDOM absorption and fluorescence were measured at the same time as the sunlight-exposed samples. Subsequently, spectrometric results in tandem with multivariate statistical analysis were used to interpret the lability vs. composition of DOM. Parallel factor analysis (PARAFAC) revealed the presence of four DOM components (C1-C4). C1 and C4 were microbial tryptophan-like, labile lighter components, while C2 and C3 were terrestrial humic like or fulvic acid type, larger aromatic refractory components. The principal component analysis (PCA) also revealed two distinct groups of DOM - C1 and C4 vs. C2 and C3. The negative PC1 loadings of C2, C3, HIX, a254 and SUVA indicated humic-like or fulvic-like structurally complex refractory aromatic DOM originated from higher plants in forested areas. C1, C4, SR, FI and BI had positive PC1 loadings, which indicated structurally simpler labile DOM were derived from agricultural areas or microbial activity. There was a decrease in dissolved organic carbon (DOC) due to combined photo- and biodegradation, and transformation of components C2

  5. Sulphur and oxygen sequestration of n-C37 and n-C38 unsaturated ketones in an immature kerogen and the release of their carbon skeletons during early stages of thermal maturation

    Science.gov (United States)

    Koopmans, M.P.; Schaeffer-Reiss, C.; De Leeuw, J. W.; Lewan, M.D.; Maxwell, J.R.; Schaeffer, P.; Sinninghe, Damste J.S.

    1997-01-01

    Sedimentary rock from the Gessoso-solfifera Formation (Messinian) in the Vena del Gesso Basin (northern Italy) containing immature (Ro = 0.25%) S-rich organic matter was artificially matured by hydrous pyrolysis at temperatures from 160 to 330??C for 72 h to study the diagenetic fate of n-C37 and n-C38 di-and tri-unsaturated methyl and ethyl ketones (alkenones) biosynthesised by several prymnesiophyte algae. During early diagenesis, the alkenones are incorporated into the kerogen by both sulphur and oxygen cross-linking as indicated by chemical degradation experiments with the kerogen of the unheated sample. Heating at temperatures between 160 and 260??C, which still represents early stages of thermal maturation, produces large amounts (up to 1 mg/g TOC) of S-bound, O-bound, and both S-and O-bound n-C37 and n-C38 skeletons, saturated n-C37 and n-C38 methyl, ethyl, and mid-chain ketones, C37 and C38 mid-chain 2,5-di-n-alkylthiophenes, C37 and C38 1,2-di-n-alkylbenzenes, and C37 and C38 n-alkanes. With increasing thermal maturation, three forms of the n-C37 and n-C38 skeletons are relatively stable (saturated hydrocarbons, 1,2-di-n-alkylbenzenes and saturated ketones), whereas the S-and O-bound skeletons are relatively labile. These results suggest that in natural situations saturated ketones with an n-C37 and n-C38 skeleton can be expected as well as the corresponding hydrocarbons. Copyright ?? 1997 Elsevier Science Ltd.

  6. Sulphur and oxygen sequestration of n-C{sub 37} and n-C{sub 38} unsaturated ketones in an immature kerogen and the release of their carbon skeletons during early stages of thermal maturation

    Energy Technology Data Exchange (ETDEWEB)

    Koopmans, M.P.; De Leeuw, J.W.; Damste, J.S.S. [Netherlands Institute for Sea Research (NIOZ), Den Burg (Netherlands)] [and others

    1997-06-01

    Sedimentary rock from the Gessoso-solfifera Formation (Messinian) in the Vena del Gesso Basin (northern Italy) containing immature (R{sub o} = 0.25%) S-rich organic matter was artificially matured by hydrous pyrolysis at temperatures from 160 to 330{degrees}C for 72 h to study the diagenetic fate of n-C{sub 37} and n-C{sub 38} di- and tri-unsaturated methyl and ethyl ketones (alkenones) biosynthesised by several prymnesiophyte algae. During early diagenesis, the alkenones are incorporated into the kerogen by both sulphur and oxygen cross-linking as indicated by chemical degradation experiments with the kerogen of the unheated sample. Heating at temperatures between 160 and 260{degrees}C, which still represents early stages of thermal maturation, produces large amounts (up to 1 mg/g TOC) of S-bound, O-bound, and both S- and O-bound n-C{sub 37} and n-C{sub 38} skeletons, saturated n-C{sub 37} and n-C{sub 38} methyl, ethyl, and mid-chain ketones, C{sub 37} and C{sub 38} mid-chain 2,5-di-n-alkylthiophenes, C{sub 37} and C{sub 38} 1,2-di-n-alkylbenzenes, and C{sub 37} and C{sub 38} n-alkanes. With increasing thermal maturation, three forms of the n-C{sub 37} and n-C{sub 38} skeletons are relatively stable (saturated hydrocarbons, 1,2-di-n-alkylbenzenes and saturated ketones), whereas the S- and O-bound skeletons are relatively labile. These results suggest that in natural situations saturated ketones with an n-C{sub 37} and n-C{sub 38} skeleton can be expected as well as the corresponding hydrocarbons. 58 refs., 8 figs., 2 tabs.

  7. Sulphur and oxygen sequestration of n-C 37 and n-C 38 unsaturated ketones in an immature kerogen and the release of their carbon skeletons during early stages of thermal maturation

    Science.gov (United States)

    Koopmans, Martin P.; Schaeffer-Reiss, Christine; de Leeuw, Jan W.; Lewan, Michael D.; Maxwell, James R.; Schaeffer, Philippe; Sinninghe Damsté, Jaap S.

    1997-06-01

    Sedimentary rock from the Gessoso-solfifera Formation (Messinian) in the Vena del Gesso Basin (northern Italy) containing immature ( Ro = 0.25%) S-rich organic matter was artificially matured by hydrous pyrolysis at temperatures from 160 to 330°C for 72 h to study the diagenetic fate of n-C 37 and n-C 38 di- and tri-unsaturated methyl and ethyl ketones (alkenones) biosynthesised by several prymnesiophyte algae. During early diagenesis, the alkenones are incorporated into the kerogen by both sulphur and oxygen cross-linking as indicated by chemical degradation experiments with the kerogen of the unheated sample. Heating at temperatures between 160 and 260°C, which still represents early stages of thermal maturation, produces large amounts (up to 1 mg/g TOC) of S-bound, O-bound, and both S- and O-bound n-C 37 and n-C 38 skeletons, saturated n-C 37 and n-C38 methyl, ethyl, and mid-chain ketones, C 37 and C 38 mid-chain 2,5-di- n-alkylthiophenes, C 37 and C 38 1,2-di- n-alkylbenzenes, and C 37 and C 38n-alkanes. With increasing thermal maturation, three forms of the n-C 37 and n-C 38 skeletons are relatively stable (saturated hydrocarbons, 1,2-di- n-alkylbenzenes and saturated ketones), whereas the S- and O-bound skeletons are relatively labile. These results suggest that in natural situations saturated ketones with an n-C 37 and n-C 38 skeleton can be expected as well as the corresponding hydrocarbons.

  8. Mass loss and nutrient concentrations of buried wood as a function of organic matter removal, soil compaction, and vegetation control in a regenerating oak-pine forest

    Science.gov (United States)

    Felix Ponder; John M. Kabrick; Mary Beth Adams; Deborah S. Page-Dumroese; Marty F. Jurgensen

    2017-01-01

    Mass loss and nutrient concentrations of northern red oak (Quercus rubra) and white oak (Q. alba) wood stakes were measured 30 months after their burial in the upper 10 cm of soil in a regenerating forest after harvesting and soil disturbance. Disturbance treatments were two levels of organic matter (OM) removal (only...

  9. Dynamics of metal-humate complexation equilibria as revealed by isotope exchange studies - a matter of concentration and time

    Science.gov (United States)

    Lippold, Holger; Eidner, Sascha; Kumke, Michael U.; Lippmann-Pipke, Johanna

    2017-01-01

    Complexation with dissolved humic matter can be crucial in controlling the mobility of toxic or radioactive contaminant metals. For speciation and transport modelling, a dynamic equilibrium process is commonly assumed, where association and dissociation run permanently. This is, however, questionable in view of reported observations of a growing resistance to dissociation over time. In this study, the isotope exchange principle was employed to gain direct insight into the dynamics of the complexation equilibrium, including kinetic inertisation phenomena. Terbium(III), an analogue of trivalent actinides, was used as a representative of higher-valent metals. Isotherms of binding to (flocculated) humic acid, determined by means of 160Tb as a radiotracer, were found to be identical regardless of whether the radioisotope was introduced together with the bulk of stable 159Tb or subsequently after pre-equilibration for up to 3 months. Consequently, there is a permanent exchange of free and humic-bound Tb since all available binding sites are occupied in the plateau region of the isotherm. The existence of a dynamic equilibrium was thus evidenced. There was no indication of an inertisation under these experimental conditions. If the small amount of 160Tb was introduced prior to saturation with 159Tb, the expected partial desorption of 160Tb occurred at much lower rates than observed for the equilibration process in the reverse procedure. In addition, the rates decreased with time of pre-equilibration. Inertisation phenomena are thus confined to the stronger sites of humic molecules (occupied at low metal concentrations). Analysing the time-dependent course of isotope exchange according to first-order kinetics indicated that up to 3 years are needed to attain equilibrium. Since, however, metal-humic interaction remains reversible, exchange of metals between humic carriers and mineral surfaces cannot be neglected on the long time scale to be considered in predictive

  10. A case of extreme particulate matter concentrations over Central Europe caused by dust emitted over the southern Ukraine

    Directory of Open Access Journals (Sweden)

    W. Birmili

    2008-02-01

    Full Text Available On 24 March 2007, an extraordinary dust plume was observed in the Central European troposphere. Satellite observations revealed its origins in a dust storm in Southern Ukraine, where large amounts of soil were resuspended from dried-out farmlands at wind gusts up to 30 m s−1. Along the pathway of the plume, maximum particulate matter (PM10 mass concentrations between 200 and 1400 μg m−3 occurred in Slovakia, the Czech Republic, Poland, and Germany. Over Germany, the dust plume was characterised by a volume extinction coefficient up to 400 Mm−1 and a particle optical depth of 0.71 at wavelength 0.532 μm. In-situ size distribution measurements as well as the wavelength dependence of light extinction from lidar and Sun photometer measurements confirmed the presence of a coarse particle mode with diameters around 2–3 μm. Chemical particle analyses suggested a fraction of 75% crustal material in daily average PM10 and up to 85% in the coarser fraction PM10–2.5. Based on the particle characteristics as well as a lack of increased CO and CO2 levels, a significant impact of biomass burning was ruled out. The reasons for the high particle concentrations in the dust plume were twofold: First, dust was transported very rapidly into Central Europe in a boundary layer jet under dry conditions. Second, the dust plume was confined to a relatively stable boundary layer of 1.4–1.8 km height, and could therefore neither expand nor dilute efficiently. Our findings illustrate the capacity of combined in situ and remote sensing measurements to characterise large-scale dust plumes with a variety of aerosol parameters. Although such plumes from Southern Eurasia seem to occur rather infrequently in Central Europe, its unexpected features highlights the need to improve the description of dust emission, transport and transformation processes needs, particularly when facing the

  11. Disinfection Byproduct Formation in Reverse-Osmosis Concentrated and Lyophilized Natural Organic Matter from a Drinking Water Source

    Science.gov (United States)

    Drinking water treatment and disinfection byproduct (DBP) research can be complicated by natural organic matter (NOM) temporal variability. NOM preservation by lyophilization (freeze-drying) has been long practiced to address this issue; however, its applicability for drinking wa...

  12. Olive Oil Supplements Ameliorate Endothelial Dysfunction Caused by Concentrated Ambient Particulate Matter Exposure in Healthy Human Volunteers

    Science.gov (United States)

    Context: Exposure to ambient particulate matter (PM) induces endothelial dysfunction, a risk factor for clinical cardiovascular events and progression of atherosclerosis. Dietary supplements such as olive oil and fish oil have beneficial effects on endothelial function, and ther...

  13. Enhancing Signal Output and Avoiding BOD/Toxicity Combined Shock Interference by Operating a Microbial Fuel Cell Sensor with an Optimized Background Concentration of Organic Matter

    Directory of Open Access Journals (Sweden)

    Yong Jiang

    2016-08-01

    Full Text Available In the monitoring of pollutants in an aquatic environment, it is important to preserve water quality safety. Among the available analysis methods, the microbial fuel cell (MFC sensor has recently been used as a sustainable and on-line electrochemical microbial biosensor for biochemical oxygen demand (BOD and toxicity, respectively. However, the effect of the background organic matter concentration on toxicity monitoring when using an MFC sensor is not clear and there is no effective strategy available to avoid the signal interference by the combined shock of BOD and toxicity. Thus, the signal interference by the combined shock of BOD and toxicity was systematically studied in this experiment. The background organic matter concentration was optimized in this study and it should be fixed at a high level of oversaturation for maximizing the signal output when the current change (ΔI is selected to correlate with the concentration of a toxic agent. When the inhibition ratio (IR is selected, on the other hand, it should be fixed as low as possible near the detection limit for maximizing the signal output. At least two MFC sensors operated with high and low organic matter concentrations and a response chart generated from pre-experiment data were both required to make qualitative distinctions of the four types of combined shock caused by a sudden change in BOD and toxicity.

  14. Contribution to physico-chemical study of Timahdit bituminous schists (Morocco): Organic matters and metalloporphyrins

    International Nuclear Information System (INIS)

    Saoiabi, A.

    1982-01-01

    The Timahdit bituminous schists have been analysed by different methods. The experimental results obtained using these methods concern the behaviour of the schists and the Kerogen facing the pyrolysis, as well as the separation of the hydrocarbons and the metalloporphyrins. For this purpose the techniques used are: 'Rock Eval' pyrolysis, thermogravimetric analysis and electron paramagnetic resonance (E.P.R.) for the raw rock and the Kerogen; infrared (I.R.), gas chromatography and E.P.R. for the extracted organic matters; E.P.R., I.R., nuclear magnetic resonance (N.M.R.), ultraviolet (U.V.) and mass spectrometry for the metalloporphyrins identification and characterization. The analysis of these schists has shown that: We can extract per solvent only 1% of organic matters, ferric oxide hasn't any effect neither on the pyrolysis nor on the organic matters extraction and that the Kerogen of these schists are relatively rich in hydrocarbonic compounds. The gas chromatography reveal the presence of alkanes with odd number of carbons and isoprenoids. All these criteria indicate an immature, little developped organic matter which having probably a marine origin but possessing a good oil potential. It has also been observed that a part of Iron, Nickel and Vanadium in the schists are incorporated into the organic matters. Nickel and Vanadium are into macrocycles which are porphyrins. A method for extracting and separating these porphyrins has been developped. 43 figs., 21 tabs., 58 refs. (author)

  15. Prediction of Hourly Particulate Matter Concentrations in Chiangmai, Thailand Using MODIS Aerosol Optical Depth and Ground-Based Meteorological Data

    Directory of Open Access Journals (Sweden)

    Thongchai Kanabkaew

    2013-07-01

    Full Text Available Various extreme events recorded over the world have been recognized as scientific-based evidence from possible climate change and variability. The incidence of increasing forest fires and intensive agricultural field burning in Chiangmai and Northern Thailand due to favor conditions may also due to a likely increase of droughts caused by the changing climate. Smog from biomass burning, particularly particulate matter (PM seriously affects health and the environment. Lack and sparse of ground monitors may cause unreliability for warning information. Satellite remote sensing is now a promising technology for air quality prediction at ground level. This study was to investigate the statistical model for predicting PM concentration using satellite data. Aerosol optical depth (AOD data were gathered from MODIS-Terra platform while hourly PM2.5 and PM10 data were collected from the Pollution Control Department. The relationship between AOD and hourly PM over Chiangmai was addressed by Model I-Simple linear regression and Model II-Multiple linear regression with ground-based meteorological data correction. The data used for the statistical analyses were from smog period in 2012 (January-April. Results revealed that AOD and hourly PM in Model I were positively correlated with the coefficient of determination (R2 of 0.22 and 0.21, respectively for PM2.5 and PM10. The relationship between AOD and hourly PM was improved significantly when correcting with relative humidity and temperature data. The model II gave R2 of 0.77 and 0.71, respectively for PM2.5 and PM10. To investigate the validity of model, the regression equation obtained from Model II was then applied with smog data over Chiangmai in March 2007. The model performed reasonably with R2 of 0.74. The model applications would provide supplementary data to other areas with similar conditions and without air quality monitoring stations, and reduce false warning the level of air pollution associated

  16. An exploratory analysis of the relationship between ambient ozone and particulate matter concentrations during early pregnancy and selected birth defects in Texas

    International Nuclear Information System (INIS)

    Vinikoor-Imler, Lisa C.; Stewart, Thomas G.; Luben, Thomas J.; Davis, J. Allen; Langlois, Peter H.

    2015-01-01

    We performed an exploratory analysis of ozone (O 3 ) and fine particulate matter (PM 2.5 ) concentrations during early pregnancy and multiple types of birth defects. Data on births were obtained from the Texas Birth Defects Registry (TBDR) and the National Birth Defects Prevention Study (NBDPS) in Texas. Air pollution concentrations were previously determined by combining modeled air pollution concentrations with air monitoring data. The analysis generated hypotheses for future, confirmatory studies; although many of the observed associations were null. The hypotheses are provided by an observed association between O 3 and craniosynostosis and inverse associations between PM 2.5 and septal and obstructive heart defects in the TBDR. Associations with PM 2.5 for septal heart defects and ventricular outflow tract obstructions were null using the NBDPS. Both the TBDR and the NBPDS had inverse associations between O 3 and septal heart defects. Further research to confirm the observed associations is warranted. - Highlights: • Air pollution concentrations combined modeled air data and air monitoring data. • No associations were observed between the majority of birth defects and PM 2.5 and O 3 . • Estimated associations between PM 2.5 and certain heart defects varied by dataset. • Results were suggestive of an inverse association between O 3 and septal heart defects. • Higher O 3 concentrations may be associated with increased odds of craniosynostosis. - Although most observed associations between ozone and fine particulate matter concentrations and birth defects were null, some were present and warrant further consideration

  17. The Effect of Elevated Ozone Concentrations with Varying Shading on Dry Matter Loss in a Winter Wheat-Producing Region in China.

    Science.gov (United States)

    Xu, Jingxin; Zheng, Youfei; He, Yuhong; Wu, Rongjun; Mai, Boru; Kang, Hanqing

    2016-01-01

    Surface-level ozone pollution causes crop production loss by directly reducing healthy green leaf area available for carbon fixation. Ozone and its precursors also affect crop photosynthesis indirectly by decreasing solar irradiance. Pollutants are reported to have become even more severe in Eastern China over the last ten years. In this study, we investigated the effect of a combination of elevated ozone concentrations and reduced solar irradiance on a popular winter wheat Yangmai13 (Triticum aestivum L.) at field and regional levels in China. Winter wheat was grown in artificial shading and open-top-chamber environments. Treatment 1 (T1, i.e., 60% shading with an enhanced ozone of 100±9 ppb), Treatment 2 (T2, i.e., 20% shading with an enhanced ozone of 100±9 ppb), and Control Check Treatment (CK, i.e., no shading with an enhanced ozone of 100±9 ppb), with two plots under each, were established to investigate the response of winter wheat under elevated ozone concentrations and varying solar irradiance. At the field level, linear temporal relationships between dry matter loss and cumulative stomatal ozone uptake were first established through a parameterized stomatal-flux model. At the regional level, ozone concentrations and meteorological variables, including solar irradiance, were simulated using the WRF-CMAQ model (i.e., a meteorology and air quality modeling system). These variables were then used to estimate cumulative stomatal ozone uptake for the four major winter wheat-growing provinces. The regional-level cumulative ozone uptake was then used as the independent variable in field data-based regression models to predict dry matter loss over space and time. Field-level results showed that over 85% (T1: R(2) = 0.85 & T2: R(2) = 0.89) of variation in dry matter loss was explained by cumulative ozone uptake. Dry matter was reduced by 3.8% in T1 and 2.2% in T2 for each mmol O3·m(-2) of cumulative ozone uptake. At the regional level, dry matter loss in winter

  18. The Effect of Elevated Ozone Concentrations with Varying Shading on Dry Matter Loss in a Winter Wheat-Producing Region in China.

    Directory of Open Access Journals (Sweden)

    Jingxin Xu

    Full Text Available Surface-level ozone pollution causes crop production loss by directly reducing healthy green leaf area available for carbon fixation. Ozone and its precursors also affect crop photosynthesis indirectly by decreasing solar irradiance. Pollutants are reported to have become even more severe in Eastern China over the last ten years. In this study, we investigated the effect of a combination of elevated ozone concentrations and reduced solar irradiance on a popular winter wheat Yangmai13 (Triticum aestivum L. at field and regional levels in China. Winter wheat was grown in artificial shading and open-top-chamber environments. Treatment 1 (T1, i.e., 60% shading with an enhanced ozone of 100±9 ppb, Treatment 2 (T2, i.e., 20% shading with an enhanced ozone of 100±9 ppb, and Control Check Treatment (CK, i.e., no shading with an enhanced ozone of 100±9 ppb, with two plots under each, were established to investigate the response of winter wheat under elevated ozone concentrations and varying solar irradiance. At the field level, linear temporal relationships between dry matter loss and cumulative stomatal ozone uptake were first established through a parameterized stomatal-flux model. At the regional level, ozone concentrations and meteorological variables, including solar irradiance, were simulated using the WRF-CMAQ model (i.e., a meteorology and air quality modeling system. These variables were then used to estimate cumulative stomatal ozone uptake for the four major winter wheat-growing provinces. The regional-level cumulative ozone uptake was then used as the independent variable in field data-based regression models to predict dry matter loss over space and time. Field-level results showed that over 85% (T1: R(2 = 0.85 & T2: R(2 = 0.89 of variation in dry matter loss was explained by cumulative ozone uptake. Dry matter was reduced by 3.8% in T1 and 2.2% in T2 for each mmol O3·m(-2 of cumulative ozone uptake. At the regional level, dry matter

  19. Disinfection by-product formation during chlor(am)ination of algal organic matters (AOM) extracted from Microcystis aeruginosa: effect of growth phases, AOM and bromide concentration.

    Science.gov (United States)

    Chen, Juxiang; Gao, Naiyun; Li, Lei; Zhu, Mingqiu; Yang, Jing; Lu, Xian; Zhang, Yansen

    2017-03-01

    Algae organic matter (AOM), including extracellular organic matter (EOM) and intracellular organic matter (IOM), has caused a series of problems to the water quality, among which formation of disinfection by-products (DBPs) during subsequent chlor(am)ination process was especially serious and concerned. This study characterized physicochemical properties of the EOM and IOM solution extracted from different growth phases of Microcystis aeruginosa and investigated the corresponding formation potential of DBPs during chlor(am)ination process. Besides, the effects of initial concentration of xEOM, IOM, and Br - on the yields of disinfection by-product formation potential were studied. The results indicated that the specific UV absorbance (SUVA 254 ) values of IOM and EOM (1.09 and 2.66 L/mg m) were considerably lower than that of natural organic matter (NOM) (4.79 L/mg m). Fluorescence dates showed the soluble microbial by-product was dominant in both EOM and IOM, and the tryptophan was the main component of AOM. From the excitation-emission matrix figure of EOM and IOM, we found that the content of the high molecular weight protein substance in IOM was higher than EOM. During chlorination of EOM and IOM, the yields of four kinds of DBPs followed the order trichloroethene (TCM) > 1,1-DCP > dichloride acetonitrile (DCAN) > trichloronitromethane (TCNM), while the order was TCM > DCAN > TCNM > 1,1-DCP during chloramination process. The bromine substitution factor (BSF) value increased with the increasing of the concentration of Br - . When the concentration of Br - was 500 μg/L, the BSF values of chlorination EOM and IOM were 51.1 and 68.4%, respectively. As the concentration of Br - increased, the formation of Cl-DBPs was inhibited and the formation of Br-DBPs was promoted. Graphical abstract ᅟ.

  20. Calcium, potassium, iron, copper and zinc concentrations in the white and gray matter of the cerebellum and corpus callosum in brain of four genetic mouse strains

    Energy Technology Data Exchange (ETDEWEB)

    Sergeant, C. [CNRS-Universite de Bordeaux I, UMR 5084, Chimie Nucleaire Analytique et Bio environnementale, Le Haut Vigneau, BP120, 33175 Bordeaux-Gradignan (France)]. E-mail: sergeant@cenbg.in2p3.fr; Vesvres, M.H. [CNRS-Universite de Bordeaux I, UMR 5084, Chimie Nucleaire Analytique et Bio environnementale, Le Haut Vigneau, BP120, 33175 Bordeaux-Gradignan (France); Deves, G. [CNRS-Universite de Bordeaux I, UMR 5084, Chimie Nucleaire Analytique et Bio environnementale, Le Haut Vigneau, BP120, 33175 Bordeaux-Gradignan (France); Guillou, F. [INRA-CNRS-Universite de Tours-Haras nationaux, UMR 6175, Physiologie de la Reproduction et des Comportements, 37380 Nouzilly (France)

    2005-04-01

    In the central nervous system, metallic cations are involved in oligodendrocyte maturation and myelinogenesis. Moreover, the metallic cations have been associated with pathogenesis, particularly multiple sclerosis and malignant gliomas. The brain is vulnerable to either a deficit or an excess of available trace elements. Relationship between trace metals and myelinogenesis is important in understanding a severe human pathology : the multiple sclerosis, which remains without efficient treatment. One approach to understand this disease has used mutant or transgenic mice presenting myelin deficiency or excess. But to date, the concentration of trace metals and mineral elements in white and gray matter areas in wild type brain is unknown. The aim of this study is to establish the reference concentrations of trace metals (iron, copper and zinc) and minerals (potassium and calcium) in the white and gray matter of the mouse cerebellum and corpus callosum. The brains of four different genetic mouse strains (C57Black6/SJL, C57Black6/D2, SJL and C3H) were analyzed. The freeze-dried samples were prepared to allow PIXE (Proton-induced X-ray emission) and RBS (Rutherford backscattering spectrometry) analyses with the nuclear microprobe in Bordeaux. The results obtained give the first reference values. Furthermore, one species out of the fours testes exhibited differences in calcium, iron and zinc concentrations in the white matter.

  1. Calcium, potassium, iron, copper and zinc concentrations in the white and gray matter of the cerebellum and corpus callosum in brain of four genetic mouse strains

    International Nuclear Information System (INIS)

    Sergeant, C.; Vesvres, M.H.; Deves, G.; Guillou, F.

    2005-01-01

    In the central nervous system, metallic cations are involved in oligodendrocyte maturation and myelinogenesis. Moreover, the metallic cations have been associated with pathogenesis, particularly multiple sclerosis and malignant gliomas. The brain is vulnerable to either a deficit or an excess of available trace elements. Relationship between trace metals and myelinogenesis is important in understanding a severe human pathology : the multiple sclerosis, which remains without efficient treatment. One approach to understand this disease has used mutant or transgenic mice presenting myelin deficiency or excess. But to date, the concentration of trace metals and mineral elements in white and gray matter areas in wild type brain is unknown. The aim of this study is to establish the reference concentrations of trace metals (iron, copper and zinc) and minerals (potassium and calcium) in the white and gray matter of the mouse cerebellum and corpus callosum. The brains of four different genetic mouse strains (C57Black6/SJL, C57Black6/D2, SJL and C3H) were analyzed. The freeze-dried samples were prepared to allow PIXE (Proton-induced X-ray emission) and RBS (Rutherford backscattering spectrometry) analyses with the nuclear microprobe in Bordeaux. The results obtained give the first reference values. Furthermore, one species out of the fours testes exhibited differences in calcium, iron and zinc concentrations in the white matter

  2. Unique distributions of hydrocarbons and sulphur compounds released by flash pyrolysis from the fossilised alga Gloeocapsomorpha prisca, a major constituent in one of four Ordovician kerogens

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Douglas, A.G.; Fowler, M.G.; Eglinton, T.I.

    1991-01-01

    Kerogens isolated from four rocks of Ordovician age from North America have been analysed by combined pyrolysis-gas chromatography-mass spectrometry to compare and contrast the type and distribution of sulphur-containing compounds and aromatic and aliphatic hydrocarbons present in the

  3. Hydrogen (H) Isotope Composition of Type II Kerogen Extracted by Pyrolysis-GC-MS-IRMS: Terrestrial Shale Deposits as Martian Analogs

    Science.gov (United States)

    Socki, Richard A.; Pernia, Denet; Evans, Michael; Fu, Qi; Bissada, Kadry K.; Curiale, Joseph A.; Niles, Paul B.

    2014-01-01

    Described here is a technique for H isotope analysis of organic compounds pyrolyzed from kerogens isolated from gas- and liquids-rich shales. Application of this technique will progress the understanding of the use of H isotopes not only in potential kerogen occurrences on Mars, but also in terrestrial oil and gas resource plays. H isotope extraction and analyses were carried out utilizing a CDS 5000 Pyroprobe connected to a Thermo Trace GC interfaced with a Thermo MAT 253 IRMS. Also, a split of GC-separated products was sent to a DSQ II quadrupole MS to make qualitative and semi-quantitative compositional measurements of these products. Kerogen samples from five different basins (type II and II-S) were dehydrated (heated to 80 C overnight under vacuum) and analyzed for their H isotope compositions by Pyrolysis-GC-MS-TC-IRMS. This technique takes pyrolysis products separated via GC and reacts them in a high temperature conversion furnace (1450 C), which quantitatively forms H2. Samples ranging from 0.5 to 1.0mg in size, were pyrolyzed at 800 C for 30s. and separated on a Poraplot Q GC column. H isotope data from all kerogen samples typically show enrichment in D from low to high molecular weight. H2O average delta D = -215.2 per mille (V-SMOW), ranging from - 271.8 per mille for the Marcellus Shale to -51.9 per mille for a Polish shale. Higher molecular weight compounds like toluene (C7H8) have an average delta D of -89.7 per mille, ranging from -156.0 per mille for the Barnett Shale to -50.0 per mille for the Monterey Shale. We interpret these data as representative of potential H isotope exchange between hydrocarbons and sediment pore water during basin formation. Since hydrocarbon H isotopes readily exchange with water, these data may provide some useful information on gas-water or oil-water interaction in resource plays, and further as a possible indicator of paleoenvironmental conditions. Alternatively, our data may be an indication of H isotope exchange with

  4. The Concentrations and Reduction of Airborne Particulate Matter (PM10, PM2.5, PM1 at Shelterbelt Site in Beijing

    Directory of Open Access Journals (Sweden)

    Jungang Chen

    2015-05-01

    Full Text Available Particulate matter is a serious source of air pollution in urban areas, where it exerts adverse effects on human health. This article focuses on the study of subduction of shelterbelts for atmospheric particulates. The results suggest that (1 the PM mass concentration is higher in the morning or both morning and noon inside the shelterbelts and lower mass concentrations at other times; (2 the particle mass concentration inside shelterbelt is higher than outside; (3 the particle interception efficiency of the two forest belts over the three months in descending order was PM10 > PM1 > PM2.5; and (4 the two shelterbelts captured air pollutants at rates of 1496.285 and 909.075 kg/month and the major atmospheric pollutant in Beijing city is PM10. Future research directions are to study PM mass concentration variation of shelterbelt with different tree species and different configuration.

  5. Temporal variations in C-13 and C-14 concentrations in particulate organic matter from the southern North Sea

    NARCIS (Netherlands)

    Megens, L.; Plicht, J. van der; Leeuw, J.W. de

    As a new approach for the characterization and determination of the origin of particulate organic matter (POM) in coastal waters, we measured the 14C activity and 13C/12C isotope ratios and applied molecular analysis by means of AMS, IRMS and pyrolysis-GCMS for both bulk samples and isolated

  6. Filtration and clearance rates of Anadara grandis juveniles (Pelecypoda, Arcidae with different temperatures and suspended matter concentrations

    Directory of Open Access Journals (Sweden)

    Anselmo Miranda-Baeza

    2006-09-01

    Full Text Available The mangrove cockle Anadara grandis (Broderip and Sowerby, 1829 is a potential candidate for aquaculture and for bioremediation of aquaculture effluents in the tropical and subtropical coastal areas of the eastern Pacific Ocean. Laboratory-produced spat are available, but there is no information on their responses to the range of environmental conditions to which they might be subject during the growth cycle. The aim of this study was to evaluate the filtration and clearance rates of A. grandis spat (shell length 9.50±0.37 mm with a food concentration (7.5 mg∙l-1 at four different temperatures (22, 25, 28 and 31 ºC, with pH = 7.5±0.2 and O2 concentration of 6.4±0.5 mg·l-1; experiment one; and with a temperature (25 °C and five concentrations of suspended matter (from 7.5 to 29 mg·l-1 and pH and O2 values of 7.9±0.2 and 6.8± 0.4 mg·l-1; experiment two. Filtration and clearance rates were highest at 25 ºC and significantly different (p.05. In the second experiment filtration increased according to the amount of food available, but there were no significant differences (p>.05 between 7.5 and 11 mg·l-1 and from 22.4 to 29 mg·l-1. The trend was similar for clearance, and in this case significant differences were found (pLa almeja Anadara grandis (Broderip and Sowerby, 1829 es un candidato potencial para la acuicultura y la biorremediación de efluentes acuícolas en las áreas costeras tropicales y subtropicales del océano Pacífico oriental. Se dispone de semilla producida en laboratorio, sin embargo no hay información sobre sus respuestas a los intervalos de las condiciones ambientales a las cuales puede estar sujeta durante el periodo de crecimiento. El objetivo de este estudio fue evaluar las tasas de filtración y de clarificación de semilla de A. grandis (largo de la concha= 9.50±0.37 mm con una concentración de alimento (7.5 mg∙l-1 y cuatro diferentes temperaturas (22, 25, 28 y 31 °C con pH= 7.5±0.2, concentración de O

  7. The Effect of Mississippi River Discharge on the Concentration and Composition of Particulate Matter along the Texas-Louisiana Shelf during Summers 2012 and 2013

    Science.gov (United States)

    Richardson, M. J.; Zuck, N.; Gardner, W. D.

    2016-02-01

    Flow from the Mississippi-Atchafalaya River System generally peaks during the spring freshet, discharging nutrient-rich fresh water and sediment into the northern Gulf of Mexico. The peak discharge varies year to year as a result of varying drought or flood conditions in the Mississippi watershed. When compared to an 8-year climatological average, summer 2012 is characterized by low discharge into the northern Gulf of Mexico, whereas summer 2013 is characterized by average discharge conditions. Water samples were collected during four cruises during June and August of 2012 and 2013 to assess the changes in concentration and composition of bulk particulate matter. While no consistent relationship between particulate matter composition and hypoxia was observed, there are several statistically significant seasonal and inter-annual changes in the concentration and composition of particulate matter associated with varying river discharge. There is also evidence that some sub-pycnocline turbidity and chlorophyll-a may be due to in situ primary productivity, rather than settled plankton containing chlorophyll-a.

  8. Effects of sulfur and monensin concentrations on in vitro dry matter disappearance, hydrogen sulfide production, and volatile fatty acid concentrations in batch culture ruminal fermentations.

    Science.gov (United States)

    Smith, D R; Dilorenzo, N; Leibovich, J; May, M L; Quinn, M J; Homm, J W; Galyean, M L

    2010-04-01

    Effects of monensin (MON) and S on in vitro fermentation and H(2)S production were evaluated in 2 experiments. In Exp. 1, 2 ruminally cannulated steers were adapted (>14 d) to a 75% concentrate diet [steam-flaked corn (SFC)-based], and ruminal fluid was collected approximately 4 h after feeding. Substrate composed (DM basis) of 85.2% SFC, 9% alfalfa hay, 5% cottonseed meal, and 0.8% urea was added with ruminal fluid and buffer to sealed 125-mL serum bottles to allow for gas collection. A Na(2)SO(4) solution was added to yield S equivalent to 0.2, 0.4, and 0.8% of substrate DM, and MON was included at 0, 2, 4, and 6 mg/L of culture volume. Bottle head-space gas was analyzed for H(2)S. No MON (P = 0.29) or MON x S interaction (P = 0.41) effects were detected for H(2)S production. Increasing S linearly increased (P molar proportions of acetate, butyrate, and the acetate:propionate ratio (A:P), and linearly increased (P 21 d) to a 75% concentrate diet (SFC base) that contained 15% (DM basis) wet corn distillers grains plus solubles (WDGS) and MON at 22 mg/kg of DM. In vitro substrate DM was composed of 75.4% SFC, 15% WDGS, 9% alfalfa hay, and 0.6% urea, and S and MON concentrations were the same as in Exp. 1. No effects of MON (P = 0.93) or the MON x S interaction (P = 0.99) were noted for H(2)S production; however, increasing S linearly increased (P molar proportions of acetate, butyrate, and A:P and linearly increased (P molar proportions were evident with MON regardless of S concentration.

  9. The impact of photovoltaic (PV) installations on downwind particulate matter concentrations: Results from field observations at a 550-MWAC utility-scale PV plant.

    Science.gov (United States)

    Ravikumar, Dwarakanath; Sinha, Parikhit

    2017-10-01

    With utility-scale photovoltaic (PV) projects increasingly developed in dry and dust-prone geographies with high solar insolation, there is a critical need to analyze the impacts of PV installations on the resulting particulate matter (PM) concentrations, which have environmental and health impacts. This study is the first to quantify the impact of a utility-scale PV plant on PM concentrations downwind of the project site. Background, construction, and post-construction PM 2.5 and PM 10 (PM with aerodynamic diameters construction through a wind-shielding effect. The results show that the (1) confidence intervals of the mean PM concentrations during construction overlap with or are lower than background concentrations for three of the four BAM stations; and (2) post-construction PM 2.5 and PM 10 concentrations downwind of the PV installation are significantly lower than the background concentrations at three of the four BAM stations. At the fourth BAM station, downwind post-construction PM 2.5 and PM 10 concentrations increased marginally by 5.7% and 2.6% of the 24-hr ambient air quality standards defined by the U.S. Environmental Protection Agency, respectively, when compared with background concentrations, with the PM 2.5 increase being statistically insignificant. This increase may be due to vehicular emissions from an access road near the southwest corner of the site or a drainage berm near the south station. The findings demonstrate the overall environmental benefit of downwind PM emission abatement from a utility-scale PV installation in desert conditions due to wind shielding. With PM emission reductions observed within 10 months of completion of construction, post-construction monitoring of downwind PM levels may be reduced to a 1-yr period for other projects with similar soil and weather conditions. This study is the first to analyze impact of a utility photovoltaic (PV) project on downwind particulate matter (PM) concentration in desert conditions. The PM

  10. Association of circulating active and total ghrelin concentrations with dry matter intake, growth, and carcass characteristics of finishing beef cattle

    Science.gov (United States)

    Ghrelin is a gut peptide that when acylated is thought to stimulate appetite. Circulating ghrelin concentrations could potentially be used as a predictor of DMI in cattle. The objective of this experiment was to determine the association of circulating ghrelin concentrations with DMI and other produ...

  11. Low correlation between household carbon monoxide and particulate matter concentrations from biomass-related pollution in three resource-poor settings

    International Nuclear Information System (INIS)

    Klasen, Elizabeth M.; Wills, Beatriz; Naithani, Neha; Gilman, Robert H.; Tielsch, James M.; Chiang, Marilu; Khatry, Subarna; Breysse, Patrick N.; Menya, Diana; Apaka, Cosmas; Carter, E. Jane; Sherman, Charles B.; Miranda, J. Jaime; Checkley, William

    2015-01-01

    Household air pollution from the burning of biomass fuels is recognized as the third greatest contributor to the global burden of disease. Incomplete combustion of biomass fuels releases a complex mixture of carbon monoxide (CO), particulate matter (PM) and other toxins into the household environment. Some investigators have used indoor CO concentrations as a reliable surrogate of indoor PM concentrations; however, the assumption that indoor CO concentration is a reasonable proxy of indoor PM concentration has been a subject of controversy. We sought to describe the relationship between indoor PM 2.5 and CO concentrations in 128 households across three resource-poor settings in Peru, Nepal, and Kenya. We simultaneously collected minute-to-minute PM 2.5 and CO concentrations within a meter of the open-fire stove for approximately 24 h using the EasyLog-USB-CO data logger (Lascar Electronics, Erie, PA) and the personal DataRAM-1000AN (Thermo Fisher Scientific Inc., Waltham, MA), respectively. We also collected information regarding household construction characteristics, and cooking practices of the primary cook. Average 24 h indoor PM 2.5 and CO concentrations ranged between 615 and 1440 μg/m 3 , and between 9.1 and 35.1 ppm, respectively. Minute-to-minute indoor PM 2.5 concentrations were in a safe range (<25 μg/m 3 ) between 17% and 65% of the time, and exceeded 1000 μg/m 3 between 8% and 21% of the time, whereas indoor CO concentrations were in a safe range (<7 ppm) between 46% and 79% of the time and exceeded 50 ppm between 4%, and 20% of the time. Overall correlations between indoor PM 2.5 and CO concentrations were low to moderate (Spearman ρ between 0.59 and 0.83). There was also poor agreement and evidence of proportional bias between observed indoor PM 2.5 concentrations vs. those estimated based on indoor CO concentrations, with greater discordance at lower concentrations. Our analysis does not support the notion that indoor CO concentration is a

  12. Ambient concentrations of total suspended particulate matter and its elemental constituents at the wider area of the mining facilities of TVX Hellas in Chalkidiki, Greece.

    Science.gov (United States)

    Gaidajis, George

    2003-01-01

    To assess ambient air quality at the wider area of TVX Hellas mining facilities, the Total Suspended Particulate matter (TSP) and its content in characteristic elements, i.e., As, Cd, Cu, Fe, Mn, Pb, Zn are being monitored for more than thirty months as part of the established Environmental Monitoring Program. High Volume air samplers equipped with Tissue Quartz filters were employed for the collection of TSP. Analyses were effected after digestion of the suspended particulate with an HNO3-HCl solution and determination of elemental concentrations with an Atomic Absorption Spectroscopy equipped with graphite furnace. The sampling stations were selected to record representatively the existing ambient air quality in the vicinity of the facilities and at remote sites not affected from industrial activities. Monitoring data indicated that the background TSP concentrations ranged from 5-60 microg/m3. Recorded TSP concentrations at the residential sites close to the facilities ranged between 20-100 microg/m3, indicating only a minimal influence from the mining and milling activities. Similar spatial variation was observed for the TSP constituents and specifically for Pb and Zn. To validate the monitoring procedures, a parallel sampling campaign took place with different High Volume samplers at days where low TSP concentrations were expected. The satisfactory agreement (+/- 11%) at low concentrations (50-100 microg/m3) clearly supported the reproducibility of the techniques employed specifically at the critical range of lower concentrations.

  13. Metabolite concentrations in supraventricular white matter from teenage to early old age: A short echo time 1H magnetic resonance spectroscopy (MRS) study

    Energy Technology Data Exchange (ETDEWEB)

    Raininko, Raili (Dept. of Radiology, Uppsala Univ., Uppsala (Sweden)), e-mail: raili.raininko@radiol.uu.se; Mattsson, Peter (Dept. of Neuroscience, Neurology, Uppsala Univ., Uppsala (Sweden))

    2010-04-15

    Background: Age- and sex-related changes of metabolites in healthy adult brains have been examined with different 1H magnetic resonance spectroscopy (MRS) methods in varying populations, and with differing results. A long repetition time and short echo time technique reduces quantification errors due to T1 and T2 relaxation effects and makes it possible to measure metabolites with short T2 relaxation times. Purpose: To examine the effect of age on the metabolite concentrations measured by 1H MRS in normal supraventricular white matter using a long repetition time (TR) and a short echo time (TE). Material and Methods: Supraventricular white matter of 57 healthy subjects (25 women, 32 men), aged 13 to 72 years, was examined with a single-voxel MRS at 1.5T using a TR of 6000 ms and a TE of 22 ms. Tissue water was used as a reference in quantification. Results: Myoinositol increased slightly and total N-acetyl aspartate (NAA) decreased slightly with increasing age. Glutamine/glutamate complex (Glx) showed U-shaped age dependence, with highest concentrations in the youngest and oldest subjects. No significant age dependence was found in total choline and total creatine. No gender differences were found. Macromolecule/ lipid (ML) fractions were reliably measurable only in 36/57 or even fewer subjects and showed very large deviations. Conclusion: The concentrations of several metabolites in cerebral supraventricular white matter are age dependent on 1H MRS, even in young and middle-aged people, and age dependency can be nonlinear. Each 1H MRS study of the brain should therefore take age into account, whereas sex does not appear to be so important. The use of macromolecule and lipid evaluations is compromised by less successful quantification and large variations in healthy people

  14. Metabolite concentrations in supraventricular white matter from teenage to early old age: A short echo time {sup 1}H magnetic resonance spectroscopy (MRS) study

    Energy Technology Data Exchange (ETDEWEB)

    Raininko, Raili [Dept. of Radiology, Uppsala Univ., Uppsala (Sweden)], e-mail: raili.raininko@radiol.uu.se; Mattsson, Peter [Dept. of Neuroscience, Neurology, Uppsala Univ., Uppsala (Sweden)

    2010-04-15

    Background: Age- and sex-related changes of metabolites in healthy adult brains have been examined with different {sup 1}H magnetic resonance spectroscopy (MRS) methods in varying populations, and with differing results. A long repetition time and short echo time technique reduces quantification errors due to T1 and T2 relaxation effects and makes it possible to measure metabolites with short T2 relaxation times. Purpose: To examine the effect of age on the metabolite concentrations measured by 1H MRS in normal supraventricular white matter using a long repetition time (TR) and a short echo time (TE). Material and Methods: Supraventricular white matter of 57 healthy subjects (25 women, 32 men), aged 13 to 72 years, was examined with a single-voxel MRS at 1.5T using a TR of 6000 ms and a TE of 22 ms. Tissue water was used as a reference in quantification. Results: Myoinositol increased slightly and total N-acetyl aspartate (NAA) decreased slightly with increasing age. Glutamine/glutamate complex (Glx) showed U-shaped age dependence, with highest concentrations in the youngest and oldest subjects. No significant age dependence was found in total choline and total creatine. No gender differences were found. Macromolecule/ lipid (ML) fractions were reliably measurable only in 36/57 or even fewer subjects and showed very large deviations. Conclusion: The concentrations of several metabolites in cerebral supraventricular white matter are age dependent on 1H MRS, even in young and middle-aged people, and age dependency can be nonlinear. Each 1H MRS study of the brain should therefore take age into account, whereas sex does not appear to be so important. The use of macromolecule and lipid evaluations is compromised by less successful quantification and large variations in healthy people.

  15. Metabolite concentrations in supraventricular white matter from teenage to early old age: A short echo time 1H magnetic resonance spectroscopy (MRS) study

    International Nuclear Information System (INIS)

    Raininko, Raili; Mattsson, Peter

    2010-01-01

    Background: Age- and sex-related changes of metabolites in healthy adult brains have been examined with different 1 H magnetic resonance spectroscopy (MRS) methods in varying populations, and with differing results. A long repetition time and short echo time technique reduces quantification errors due to T1 and T2 relaxation effects and makes it possible to measure metabolites with short T2 relaxation times. Purpose: To examine the effect of age on the metabolite concentrations measured by 1H MRS in normal supraventricular white matter using a long repetition time (TR) and a short echo time (TE). Material and Methods: Supraventricular white matter of 57 healthy subjects (25 women, 32 men), aged 13 to 72 years, was examined with a single-voxel MRS at 1.5T using a TR of 6000 ms and a TE of 22 ms. Tissue water was used as a reference in quantification. Results: Myoinositol increased slightly and total N-acetyl aspartate (NAA) decreased slightly with increasing age. Glutamine/glutamate complex (Glx) showed U-shaped age dependence, with highest concentrations in the youngest and oldest subjects. No significant age dependence was found in total choline and total creatine. No gender differences were found. Macromolecule/ lipid (ML) fractions were reliably measurable only in 36/57 or even fewer subjects and showed very large deviations. Conclusion: The concentrations of several metabolites in cerebral supraventricular white matter are age dependent on 1H MRS, even in young and middle-aged people, and age dependency can be nonlinear. Each 1H MRS study of the brain should therefore take age into account, whereas sex does not appear to be so important. The use of macromolecule and lipid evaluations is compromised by less successful quantification and large variations in healthy people

  16. Molecular and elemental analyses of the carbonaceous matter in the gold and uranium bearing Vaal Reef carbon seams, Witwatersrand sequence

    International Nuclear Information System (INIS)

    Zumberge, J.E.; Sigleo, A.C.; Nagy, B.

    1978-01-01

    The thin Vaal Reef carbon seams consist of a complex, solid, and solvent insoluble, polymer-like substance, containing mainly hydrocarbons and some organic sulphur and oxygen compounds. These carbon seams are not pure carbon, e.g. graphite, and do not contain only hydrocarbons. According to modern terminology the Vaal Reef carbonaceous matter is most appropriately referred to as kerogen rather than carbon or thucholite. This kerogen is not the result of the polymerization of gaseous or liquid hydrocarbons, but rather of the polymerization of biochemicals from decayed, primitive Precambrian micro-organisms. These microbiota formed mats in which uranium minerals and gold became incorporated before burial under younger sediments. Organic geochemistry was first developed as a means to elucidate the nature and composition of petroleum and coal. Later it was successfully used in lunar sample, planetary surface, and meteorite studies as well as in investigations of kerogens in terrestrial sediments of various ages. Considering economic geology, organic geochemistry holds promise for elucidating the origin and helping in the exploration of carbonaceous ore deposits. The purpose of this report is to review some of the major current organic geochemical methods and to illustrate these by the analysis of the Vaal Reef kerogen. The samples were analysed by a directly connected high vacuum pyrolysis system-gas chromatograph-organic mass spectrometer. Additional analyses were performed by a combined scanning electron microscope-electron microprobe, by the techniques of electron paramagnetic resonance spectroscopy, and by neutron activation analysis

  17. Development of Land Use Regression models for particulate matter and associated components in a low air pollutant concentration airshed

    NARCIS (Netherlands)

    Dirgawati, Mila; Heyworth, Jane S.; Wheeler, Amanda J.; McCaul, Kieran A.; Blake, David; Boeyen, Jonathon; Cope, Martin; Yeap, Bu Beng; Nieuwenhuijsen, Mark; Brunekreef, Bert|info:eu-repo/dai/nl/067548180; Hinwood, Andrea

    2016-01-01

    Perth, Western Australia represents an area where pollutant concentrations are considered low compared with international locations. Land Use Regression (LUR) models for PM10, PM2.5 and PM2.5 Absorbance (PM2.5Abs) along with their elemental components: Fe, K, Mn, V, S, Zn and Si were developed for

  18. A panel study of airborne particulate matter concentration and impaired cardiopulmonary function in young adults by two different exposure measurement

    Science.gov (United States)

    Hu, Li-Wen; Qian, Zhengmin (Min); Bloom, Michael S.; Nelson, Erik J.; Liu, Echu; Han, Bin; Zhang, Nan; Liu, Yimin; Ma, Huimin; Chen, Duo-Hong; Yang, Bo-Yi; Zeng, Xiao-Wen; Chen, Wen; Komppula, Mika; Leskinen, Ari; Hirvonen, Maija-Riitta; Roponen, Marjut; Jalava, Pasi; Bai, Zhipeng; Dong, Guang-Hui

    2018-05-01

    This study sought to clarify the correlation of individual exposure measurements and PM2.5 measurements collected at regulatory monitoring sites in short-term panel study settings. To achieve this goal, 30 young, healthy adult participants were assigned to three groups with 4 samplers in each group to collect individual exposures during four weekends in March 2016. Participants also completed cardiopulmonary function tests during the same periods. For comparison, ambient air pollution data were obtained from the Air Pollution Surveillance Network in Guangzhou, China. The 8-h ambient pollutant averages and group sampler concentrations were used as separate indicators of air pollution exposure. Results showed that the 8-h mean concentration of personal PM2.5 exposure was 65.09 ± 22.18 μg/m3, which was 24.34 μg/m3 statistically higher than the ambient concentrations over the same period (p < 0.05). However, these concentrations were strongly correlated (Spearman's r = 0.937, p < 0.01). Separate mixed-effect models were fit for ambient and personal exposures to estimate their associations with cardiopulmonary outcomes. Higher PM2.5 and PM10 exposures were related to lower lung function of maximal mid-expiratory flow (MMEF). A 10 μg/m3 higher PM was associated with 0.11 L/S to 0.52 L/S lower MMEF. No effects on cardiovascular function were found. In conclusion, personal PM2.5 exposure might be higher than ambient concentrations. Young, healthy adults in urban areas may experience reduced lung function (lower MMEF), even after just 8 h of exposure to PM2.5 and PM10.

  19. Deriving Total Suspended Matter Concentration from the Near-Infrared-Based Inherent Optical Properties over Turbid Waters: A Case Study in Lake Taihu

    Directory of Open Access Journals (Sweden)

    Wei Shi

    2018-02-01

    Full Text Available Normalized water-leaving radiance spectra nLw(λ, particle backscattering coefficients bbp(λ in the near-infrared (NIR wavelengths, and total suspended matter (TSM concentrations over turbid waters are analytically correlated. To demonstrate the use of bbp(λ in the NIR wavelengths in coastal and inland waters, we used in situ optics and TSM data to develop two TSM algorithms from measurements of the Visible Infrared Imaging Radiometer Suite (VIIRS onboard the Suomi National Polar-orbiting Partnership (SNPP using backscattering coefficients at the two NIR bands bbp(745 and bbp(862 for Lake Taihu. The correlation coefficients between the modeled TSM concentrations from bbp(745 and bbp(862 and the in situ TSM are 0.93 and 0.92, respectively. A different in situ dataset acquired between 2012 and 2016 for Lake Taihu was used to validate the performance of the NIR TSM algorithms for VIIRS-SNPP observations. TSM concentrations derived from VIIRS-SNPP observations with these two NIR bbp(λ-based TSM algorithms matched well with in situ TSM concentrations in Lake Taihu between 2012 and 2016. The normalized root mean square errors (NRMSEs for the two NIR algorithms are 0.234 and 0.226, respectively. The two NIR-based TSM algorithms are used to compute the satellite-derived TSM concentrations to study the seasonal and interannual variability of the TSM concentration in Lake Taihu between 2012 and 2016. In fact, the NIR-based TSM algorithms are analytically based with minimal in situ data to tune the coefficients. They are not sensitive to the possible nLw(λ saturation in the visible bands for highly turbid waters, and have the potential to be used for estimation of TSM concentrations in turbid waters with similar NIR nLw(λ spectra as those in Lake Taihu.

  20. Predicting residential indoor concentrations of nitrogen dioxide, fine particulate matter, and elemental carbon using questionnaire and geographic information system based data

    Science.gov (United States)

    Baxter, Lisa K.; Clougherty, Jane E.; Paciorek, Christopher J.; Wright, Rosalind J.; Levy, Jonathan I.

    Previous studies have identified associations between traffic-related air pollution and adverse health effects. Most have used measurements from a few central ambient monitors and/or some measure of traffic as indicators of exposure, disregarding spatial variability and factors influencing personal exposure-ambient concentration relationships. This study seeks to utilize publicly available data (i.e., central site monitors, geographic information system, and property assessment data) and questionnaire responses to predict residential indoor concentrations of traffic-related air pollutants for lower socioeconomic status (SES) urban households. As part of a prospective birth cohort study in urban Boston, we collected indoor and outdoor 3-4 day samples of nitrogen dioxide (NO 2) and fine particulate matter (PM 2.5) in 43 low SES residences across multiple seasons from 2003 to 2005. Elemental carbon (EC) concentrations were determined via reflectance analysis. Multiple traffic indicators were derived using Massachusetts Highway Department data and traffic counts collected outside sampling homes. Home characteristics and occupant behaviors were collected via a standardized questionnaire. Additional housing information was collected through property tax records, and ambient concentrations were collected from a centrally located ambient monitor. The contributions of ambient concentrations, local traffic and indoor sources to indoor concentrations were quantified with regression analyses. PM 2.5 was influenced less by local traffic but had significant indoor sources, while EC was associated with traffic and NO 2 with both traffic and indoor sources. Comparing models based on covariate selection using p-values or a Bayesian approach yielded similar results, with traffic density within a 50 m buffer of a home and distance from a truck route as important contributors to indoor levels of NO 2 and EC, respectively. The Bayesian approach also highlighted the uncertanity in the

  1. Spatiotemporal Association of Real-Time Concentrations of Black Carbon (BC with Fine Particulate Matters (PM2.5 in Urban Hotspots of South Korea

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    Sungroul Kim

    2017-11-01

    Full Text Available We evaluated the spatiotemporal distributions of black carbon (BC and particulate matters with aerodynamic diameters of less than 2.5 m (PM2.5 concentrations at urban diesel engine emission (DEE hotspots of South Korea. Concentrations of BC and PM2.5 were measured at the entrance gate of two diesel bus terminals and a train station, in 2014. Measurements were conducted simultaneously at the hotspot (Site 1 and at its adjacent, randomly selected, residential areas, apartment complex near major roadways, located with the same direction of 300 m (Site 2 and 500 m (Site 3 away from Site 1 on 4 different days over the season, thrice per day; morning (n = 120 measurements for each day and site, evening (n = 120, and noon (n = 120. The median (interquartile range PM2.5 ranged from 12.6 (11.3–14.3 to 60.1 (47.0–76.0 μg/m3 while those of BC concentrations ranged from 2.6 (1.9–3.7 to 6.3 (4.2–10.3 μg/m3. We observed a strong relationship of PM2.5 concentrations between sites (slopes 0.89–0.9, the coefficient of determination 0.89–0.96 while the relationship for BC concentrations between sites was relatively weak (slopes 0.76–0.85, the coefficient of determination 0.54–0.72. PM2.5 concentrations were changed from 4% to 140% by unit increase of BC concentration, depending on site and time while likely supporting the necessity of monitoring of BC as well as PM2.5, especially at urban DEE related hotspot areas.

  2. Importance of Dissolved Neutral Hg-Sulfides, Energy Rich Organic Matter and total Hg Concentrations for Methyl Mercury Production in Sediments

    Science.gov (United States)

    Drott, A.; Skyllberg, U.

    2007-12-01

    Methyl mercury (MeHg) is the mercury form that biomagnifies to the greatest extent in aquatic food webs. Therefore information about factors determining MeHg concentrations is critical for accurate risk assessment of contaminated environments. The concentration of MeHg in wetlands and sediments is the net result of: 1) methylation rates, 2) demethylation rates, and 3) input/output processes. In this study, the main controls on Hg methylation rates and total concentrations of MeHg, were investigated at eight sites in Sweden with sediments that had been subjected to local Hg contamination either as Hg(0), or as phenyl-Hg. Sediments were selected to represent a gradient in total Hg concentration, temperature climate, salinity, primary productivity, and organic C content and quality. Most sediments were high in organic matter content due to wood fibre efflux from pulp and paper industry. The pore water was analysed for total Hg, MeHg, DOC, H2S(aq), pH, DOC, Cl and Br. The chemical speciation of Hg(II) and MeHg in pore water was calculated using equilibrium models. Potential methylation and demethylation rates in sediments were determined in incubation experiments at 23° C under N2(g) for 48 h, after addition of isotopically enriched 201Hg(II) and Me204Hg. In all surface (0-20 cm) sediments there was a significant (pdetermined specific potential methylation rate constant (Km, day-1) and % MeHg (concentrations of MeHg normalized to total Hg) in the sediment. This indicates that MeHg production overruled degradation and input/output processes of MeHg in surface sediments, and that % MeHg in surface sediments may be used as a proxy for net production of MeHg. To our knowledge, these are the first data showing significant positive relationships between short term (48 h) MeHg production and longer term accumulation of MeHg, across a range of sites with different properties (1). If MeHg was not normalized to total Hg, the relationship was not significant. For sub-sets of

  3. Chemical characteristics of dissolved organic matter (DOM) in relation to heavy metal concentrations in soil water from boreal peatlands after clear-cut harvesting

    Science.gov (United States)

    Kiikkilä, O.; Nieminen, T.; Starr, M.; Ukonmaanaho, L.

    2012-04-01

    Boreal peatlands form an important terrestrial carbon reserve and are a major source of dissolved organic matter (DOM) to surface waters, particularly when disturbed through forestry practices such as draining or timber harvesting. Heavy metals show a strong affinity to organic matter and so, along with DOM, heavy metals can be mobilized and transported from the soil to surface waters and sediments where they may become toxic to aquatic organisms and pass up the food chain. The complexation of heavy metals with DOM can be expected to be related and determined by the chemical characteristics of DOM and oxidation/reducing conditions in the peat. We extracted interstitial water from peat samples and determined the concentrations of dissolved organic carbon (DOC), dissolved organic nitrogen (DON) and Al, Cu, Zn and Fe in various fractions of DOM isolated by adsorption properties (XAD-8 fractionation) and molecular-weight (ultrafiltration). The peat samples were taken from 0-30 and 30-50 cm depth in drained peatland catchments two years after whole-tree or stem-only clear-cut harvesting (Scots pine or Norway spruce) had been carried out. The samples from the upper layer had been subject to alternating saturation/aeration conditions while the deeper layer had been continuously under the water table. The fractionation of DOC and DON according to both adsorption properties and molecular-weight fractions clearly differed between the upper and lower peat layers. While the hydrophobic acid fraction contained proportionally more DOC and DON than the hydrophilic acid fraction in the upper peat layer the results were vice versa in the lower peat layer. High-molecular-weight compounds (> 100 kDa) were proportionally more abundant in the upper and low-molecular-weight compounds (< 1 kDa) in the lower peat layer. These differences are assumed to reflect differences in the aerobic/ anaerobic conditions and degree of decomposition between the two layers. The concentrations of Zn, Al

  4. Indoor and outdoor sources of size-resolved mass concentration of particulate matter in a school gym-implications for exposure of exercising children.

    Science.gov (United States)

    Braniš, Martin; Safránek, Jiří; Hytychová, Adéla

    2011-05-01

    It has been noticed many times that schools are buildings with high levels of particulate matter concentrations. Several authors documented that concentrations of particulate matter in indoor school microenvironments exceed limits recommended by WHO namely when school buildings are situated near major roads with high traffic densities. In addition, exercise under conditions of high particulate concentrations may increase the adverse health effects, as the total particle deposition increases in proportion to minute ventilation, and the deposition fraction nearly doubles from rest to intense exercise. Mass concentrations of size-segregated aerosol were measured simultaneously in an elementary school gym and an adjacent outdoor site in the central part of Prague by two pairs of collocated aerosol monitors-a fast responding photometer DusTrak and a five stage cascade impactor. To encompass seasonal and annual differences, 89 days of measurements were performed during ten campaigns between 2005 and 2009. The average (all campaigns) outdoor concentration of PM(2.5) (28.3 μg m(-3)) measured by the cascade impactors was higher than the indoor value (22.3 μg m(-3)) and the corresponding average from the nearest fixed site monitor (23.6 μg m(-3)). Indoor and outdoor PM(2.5) concentrations exceeded the WHO recommended 24-h limit in 42% and 49% of the days measured, respectively. The correlation coefficient (r) between corresponding outdoor and indoor aerosol sizes increased with decreasing aerodynamic diameter of the collected particles (r = 0.32-0.87), suggesting a higher infiltration rate of fine and quasi-ultrafine particles. Principal component analysis revealed five factors explaining more than 82% of the data variability. The first two factors reflected a close association between outdoor and indoor fine and quasi-ultrafine particles confirming the hypothesis of high infiltration rate of particles from outdoors. The third factor indicated that human

  5. Field evaluation of a new particle concentrator- electrostatic precipitator system for measuring chemical and toxicological properties of particulate matter

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    Pakbin Payam

    2008-11-01

    Full Text Available Abstract Background A newly designed electrostatic precipitator (ESP in tandem with Versatile Aerosol Concentration Enrichment System (VACES was developed by the University of Southern California to collect ambient aerosols on substrates appropriate for chemical and toxicological analysis. The laboratory evaluation of this sampler is described in a previous paper. The main objective of this study was to evaluate the performance of the new VACES-ESP system in the field by comparing the chemical characteristics of the PM collected in the ESP to those of reference samplers operating in parallel. Results The field campaign was carried out in the period from August, 2007 to March, 2008 in a typical urban environment near downtown Los Angeles. Each sampling set was restricted to 2–3 hours to minimize possible sampling artifacts in the ESP. The results showed that particle penetration increases and ozone concentration decreases with increasing sampling flow rate, with highest particle penetration observed between 100 nm and 300 nm. A reference filter sampler was deployed in parallel to the ESP to collect concentration-enriched aerosols, and a MOUDI sampler was used to collect ambient aerosols. Chemical analysis results showed very good agreement between the ESP and MOUDI samplers in the concentrations of trace elements and inorganic ions. The overall organic compound content of PM collected by the ESP, including polycyclic aromatic hydrocarbons (PAHs, hopanes, steranes, and alkanes, was in good agreement with that of the reference sampler, with an average ESP -to -reference concentration ratio of 1.07 (± 0.38. While majority of organic compound ratios were close to 1, some of the semi-volatile organic species had slightly deviated ratios from 1, indicating the possibility of some sampling artifacts in the ESP due to reactions of PM with ozone and radicals generated from corona discharge, although positive and negative sampling artifacts in the

  6. Understanding the density of nonprofit organizations across Los Angeles neighborhoods: Does concentrated disadvantage and violent crime matter?

    Science.gov (United States)

    Wo, James C

    2018-03-01

    Although some urban sociology perspectives suggest how certain sociodeomgraphic characteristics influence nonprofit development, there is a dearth of empirical research to assess neighborhood differences in nonprofit organizations. The goal of the current study is to build upon the extant literature by examining how both concentrated disadvantage and violent crime impact nonprofit density across neighborhoods. Using data from Los Angeles census tracts from 2010 to 2012, I test for linear and nonlinear influences that these two neighborhood factors might exert on nonprofit density. Poisson regression models show that concentrated disadvantage has a nonlinear (U-shaped) effect on all forms of nonprofit density, whereas violent crime has a linear and deleterious effect on all forms of nonprofit density. These results provide important new insights for urban sociology and policy; most importantly, the extent to which neighborhoods with ongoing social problems can later respond to such problems via access to nonprofit organizations. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Particulate matter and polycyclic aromatic hydrocarbons in a selected athletic hall: ambient concentrations, origin and effects on human health

    Science.gov (United States)

    Kuskowska, Karolina; Rogula-Kozłowska, Wioletta; Rogula-Kopiec, Patrycja

    2018-01-01

    The paper presents the results of research on the concentration of 16 polycyclic aromatic hydrocarbons (PAHs) associated with total suspended particles (TSP) and their respirable fraction (PM4) in one of the Warsaw sports halls. Samples of dust were collected for 15 days simultaneously inside and outside (atmospheric air) of the sports hall. The obtained data allowed calculating diagnostic ratios indicating the origin of the PAHs and selected indicators of cumulative exposure to the PAH mixture. Both PM and PAH in the surveyed area were derived from the combustion of solid fuels; this involved pollution both in the atmospheric air and in the air inside the sports hall. It has been shown that the exposure of sports hall users to PAHs is significantly higher than the exposure resulting from concentrations recorded in the atmospheric air.

  8. Particulate matter and polycyclic aromatic hydrocarbons in a selected athletic hall: ambient concentrations, origin and effects on human health

    Directory of Open Access Journals (Sweden)

    Kuskowska Karolina

    2018-01-01

    Full Text Available The paper presents the results of research on the concentration of 16 polycyclic aromatic hydrocarbons (PAHs associated with total suspended particles (TSP and their respirable fraction (PM4 in one of the Warsaw sports halls. Samples of dust were collected for 15 days simultaneously inside and outside (atmospheric air of the sports hall. The obtained data allowed calculating diagnostic ratios indicating the origin of the PAHs and selected indicators of cumulative exposure to the PAH mixture. Both PM and PAH in the surveyed area were derived from the combustion of solid fuels; this involved pollution both in the atmospheric air and in the air inside the sports hall. It has been shown that the exposure of sports hall users to PAHs is significantly higher than the exposure resulting from concentrations recorded in the atmospheric air.

  9. Suspended particulate matter in New York City: element concentrations as a function of particle size and elevation above street

    International Nuclear Information System (INIS)

    Bauman, S.E.; Williams, E.T.; Finston, H.L.; Bond, A.H. Jr.; Lesser, P.M.S.; Ferrand, E.F.

    1977-01-01

    Aerosol samples were simultaneously collected at two street-level locations and the 16th floor, on two sides of a Manhattan city block. The results of PIXE analysis, together with CO and SO 2 data, show that the concentrations of substances emitted at street level (CO, Pb, etc) are significantly less at the 16th floor whereas particulate sulfur shows little variation. Other conclusions are presented

  10. Concentration and characterization of dissolved organic matter in the surface microlayer and subsurface water of the Bohai Sea, China

    Science.gov (United States)

    Chen, Yan; Yang, Gui-Peng; Wu, Guan-Wei; Gao, Xian-Chi; Xia, Qing-Yan

    2013-01-01

    A total of 19 sea-surface microlayer and corresponding subsurface samples collected from the Bohai Sea, China in April 2010 were analyzed for chlorophyll a, dissolved organic carbon (DOC) and its major compound classes including total dissolved carbohydrates (TDCHO, including monosaccharides, MCHO, and polysaccharides, PCHO) and total hydrolysable amino acids (THAA, including dissolved free, DFAA, and combined fraction, DCAA). The concentrations of DOC in the subsurface water ranged from 130.2 to 407.7 μM C, with an average of 225.9±75.4 μM C, while those in the surface microlayer varied between 140.1 and 330.9 μM C, with an average of 217.8±56.8 μM C. The concentrations of chlorophyll a, DOC, TDCHO and THAA in the microlayer were, respectively correlated with their subsurface water concentrations, implying that there was a strong exchange effect between the microlayer and subsurface water. The concentrations of DOC and TDCHO were negatively correlated with salinity, respectively, indicating that water mixing might play an important role in controlling the distribution of DOC and TDCHO in the water column. Major constituents of DCAA and DFAA present in the study area were glycine, alanine, glutamic acid, serine and histidine. Principal component analysis (PCA) was applied to examine the complex compositional differences that existed among the sampling sites. Our results showed that DFAA had higher mole percentages of glycine, valine and serine in the microlayer than in the subsurface water, while DCAA tended to have higher mole percentages of glutamic acid, aspartic acid, threonine, arginine, alanine, tyrosine, phenylalanine and leucine in the microlayer. The yields of TDCHO and THAA exhibited similar trends between the microlayer and subsurface water. Carbohydrate species displayed significant enrichment in the microlayer, whereas the DFAA and DCAA exhibited non-uniform enrichment in the microlayer.

  11. Temporal Dynamics in the Concentration, Flux, and Optical Properties of Tree-derived Dissolved Organic Matter (Tree-DOM) in an Epiphyte-laden Oak-cedar Forest.

    Science.gov (United States)

    Whitetree, A.; Van Stan, J. T., II; Wagner, S.; Guillemette, F.; Lewis, J.; Silva, L.; Stubbins, A.

    2017-12-01

    Studies on the fate and transport of dissolved organic matter (DOM) along the rainfall-to-discharge flow pathway typically begin in streams or soils, neglecting the initial enrichment of rainfall with DOM during contact with plant canopies. However, rain water can gather significant amounts of tree-derived DOM (tree-DOM) when it drains from the canopy, as throughfall, and down the stem, as stemflow. We examined the temporal variability of event-scale tree-DOM concentrations, yield, and optical (light absorbance and fluorescence) characteristics from an epiphyte-laden Quercus virginiana-Juniperus virginiana forest on Skidaway Island, Savannah, Georgia (USA). All tree-DOM fluxes were highly enriched compared to rainfall and epiphytes further increased concentrations. Stemflow DOC concentrations were greater than throughfall across study species, yet larger throughfall water yields produced greater DOC yields versus stemflow. Tree-DOM optical characteristics indicate it is aromatic-rich with FDOM dominated by humic-like fluorescence, containing 10-20% protein-like (tryptophan-like) fluorescence. Storm size was the only storm condition that strongly correlated with tree-DOM concentration and flux; however, throughfall and stemflow optical characteristics varied little across a wide range of storm conditions (from low magnitude events to intense tropical storms). Annual tree-DOM yields from the study forest (0.8-46 g-C m-2 yr-1) compared well to other yields along the rainfall-to- discharge flow pathway, exceeding DOM yields from some river watersheds.

  12. Concentrations of volatile organic compounds, carbon monoxide, carbon dioxide and particulate matter in buses on highways in Taiwan

    Science.gov (United States)

    Hsu, Der-Jen; Huang, Hsiao-Lin

    2009-12-01

    Although airborne pollutants in urban buses have been studied in many cities globally, long-distance buses running mainly on highways have not been addressed in this regard. This study investigates the levels of volatile organic compounds (VOCs), carbon monoxide (CO), carbon dioxide (CO 2) and particulate matter (PM) in the long-distance buses in Taiwan. Analytical results indicate that pollutants levels in long-distance buses are generally lower than those in urban buses. This finding is attributable to the driving speed and patterns of long-distance buses, as well as the meteorological and geographical features of the highway surroundings. The levels of benzene, toluene, ethylbenzene and xylene (BTEX) found in bus cabins exceed the proposed indoor VOC guidelines for aromatic compounds, and are likely attributable to the interior trim in the cabins. The overall average CO level is 2.3 ppm, with higher average level on local streets (2.9 ppm) than on highways (2.2 ppm). The average CO 2 level is 1493 ppm, which is higher than the guideline for non-industrial occupied settings. The average PM level in this study is lower than those in urban buses and IAQ guidelines set by Taiwan EPA. However, the average PM 10 and PM 2.5 is higher than the level set by WHO. Besides the probable causes mentioned above, fewer passenger movements and less particle re-suspension from bus floor might also cause the lower PM levels. Measurements of particle size distribution reveal that more than 75% of particles are in submicron and smaller sizes. These particles may come from the infiltration from the outdoor air. This study concludes that air exchange rates in long-distance buses should be increased in order to reduce CO 2 levels. Future research on long-distance buses should focus on the emission of VOCs from brand new buses, and the sources of submicron particles in bus cabins.

  13. Temporal multiscaling characteristics of particulate matter PM 10 and ground-level ozone O3 concentrations in Caribbean region

    Science.gov (United States)

    Plocoste, Thomas; Calif, Rudy; Jacoby-Koaly, Sandra

    2017-11-01

    A good knowledge of the intermittency of atmospheric pollutants is crucial for air pollution management. We consider here particulate matter PM 10 and ground-level ozone O3 time series in Guadeloupe archipelago which experiments a tropical and humid climate in the Caribbean zone. The aim of this paper is to study their scaling statistics in the framework of fully developed turbulence and Kolmogorov's theory. Firstly, we estimate their Fourier power spectra and consider their scaling properties in the physical space. The power spectra computed follows a power law behavior for both considered pollutants. Thereafter we study the scaling behavior of PM 10 and O3 time series. Contrary to numerous studies where the multifractal detrended fluctuation analysis is frequently applied, here, the classical structure function analysis is used to extract the scaling exponent or multifractal spectrum ζ(q) ; this function provides a full characterization of a process at all intensities and all scales. The obtained results show that PM 10 and O3 possess intermittent and multifractal properties. The singularity spectrum MS(α) also confirms both pollutants multifractal features. The originality of this work comes from a statistical modeling performed on ζ(q) and MS(α) by a lognormal model to compute the intermittency parameter μ. By contrast with PM 10 which mainly depends on puffs of Saharan dust (synoptic-scale), O3 is more intermittent due to variability of its local precursors. The results presented in this paper can help to better understand the mechanisms governing the dynamics of PM 10 and O3 in Caribbean islands context.

  14. Assessment of life quality in patients with bronchial asthma residing in Krakow in the areas of varying concentrations of particulate matter (PM10

    Directory of Open Access Journals (Sweden)

    Monika Ścibor

    2015-03-01

    Full Text Available Introduction. Asthma is a chronic disease, from which more and more people in the world suffer. It is connected with many bothersome symptoms and limitations, which result in decreased quality of life for the patient. Environmental and individual aspects do not necessarily affect individuals in the same way, so it is necessary to determine which factors have predominantly impacted on an individual, in order to minimize their impact and to take better control over treatment of asthma. The aim of this research was to compare the quality of life among patients with bronchial asthma living in Krakow in the areas where they get exposed to varying concentrations of particulate matter (PM10. Material and methods. The study included 98 adults diagnosed with bronchial asthma. The research was conducted using the AQLQ poll. PM10 concentration was measured in several Malopolska Air Pollution Monitoring Stations located throughout the city. Results. Analyzing the quality of life in the view of symptoms, activity limitations and emotional well being, there was a substantial statistical difference observed in people occupying the areas with different PM10 concentrations. No significant statistical difference was observed in the frequency of asthma symptoms caused by the environmental stimuli between the 2 discussed groups. One group of patients who came to the allergy clinic for control of asthma symptoms and the second group who live in the vicinity of the monitoring stations measuring PM10 concentrations. Conclusions. For many of the cases, the quality of life was not worse for patients with asthma living in an area with slightly elevated concentrations of PM10, and sometimes paradoxically the quality of life was improved. These results show that PM10 concentrations do not correlate with quality of life of asthma patients.

  15. [Effects of nitrogen deposition on the concentration and spectral characteristics of dissolved organic matter in soil solution in a young Cunninghamia lanceolata plantation.

    Science.gov (United States)

    Yuan, Xiao Chun; Chen, Yue Min; Yuan, Shuo; Zheng, Wei; Si, You Tao; Yuan, Zhi Peng; Lin, Wei Sheng; Yang, Yu Sheng

    2017-01-01

    To study the effects of nitrogen deposition on the concentration and spectral characteristics of dissolved organic matter (DOM) in the forest soil solution from the subtropical Cunninghamia lanceolata plantation, using negative pressure sampling method, the dynamics of DOM in soil solutions from 0-15 and 15-30 cm soil layer was monitored for two years and the spectroscopic features of DOM were analyzed. The results showed that nitrogen deposition significantly reduced the concentration of dissolved organic carbon (DOC), and increased the aromatic index (AI) and the humic index (HIX), but had no significant effect on dissolved organic nitrogen (DON) concentration in both soil layers. There was obvious seasonal variation in DOM concentration of the soil solution, which was prominently higher in summer and autumn than in spring and winter.Fourier-transform infrared (FTIR) absorption spectrometry indicated that the DOM in forest soil solution had absorption peaks in the similar position of six regions, being the highest in wave number of 1145-1149 cm -1 . Three-dimensional fluorescence spectra indicated that DOM was mainly consisted of protein-like substances (Ex/Em=230 nm/300 nm) and microbial degradation products (Ex/Em=275 nm/300 nm). The availability of protein-like substances from 0-15 cm soil layer was reduced in the nitrogen treatments. Nitrogen deposition significantly reduced the concentration of DOC in soil solution, maybe largely by reducing soil pH, inhibiting soil carbon mineralization and stimulating plant growth. In particular, the decline of DOC concentration in the surface layer was due to the production inhibition of the protein-like substances and carboxylic acids. Short-term nitrogen deposition might be beneficial to the maintenance of soil fertility, while the long-term accumulation of nitrogen deposition might lead to the hard utilization of soil nutrients.

  16. Effects of Center Offset and Noise on Weak-Lensing Derived Concentration-Mass Relation of Dark Matter Halos

    Science.gov (United States)

    Du, Wei; Fan, Zuhui

    2014-04-01

    With the halo catalog from the Millennium Simulation, we analyze the weak-lensing measured density profiles for clusters of galaxies, paying attention to the determination of the concentration-mass (c-M) relation, which can be biased by the center offset, selection effect, and shape noise from intrinsic ellipticities of background galaxies. Several different methods of locating the center of a cluster from weak-lensing effects alone are explored. We find that, for intermediate redshift clusters, the highest peak from our newly proposed two-scale smoothing method applied to the reconstructed convergence field, first with a smoothing scale of 2' and then 0.'5, corresponds best to the true center. Assuming the parameterized Navarro-Frenk-White profile, we fit the reduced tangential shear signals around different centers identified by different methods. It is shown that, for the ensemble median values, a center offset larger than one scale radius rs can bias the derived mass and concentration significantly lower than the true values, especially for low-mass halos. However, the existence of noise can compensate for the offset effect and reduce the systematic bias, although the scatter of mass and concentration becomes considerably larger. Statistically, the bias effect of center offset on the c-M relation is insignificant if an appropriate center finding method is adopted. On the other hand, noise from intrinsic ellipticities can bias the c-M relation derived from a sample of weak-lensing analyzed clusters if a simple χ2 fitting method is used. To properly account for the scatter and covariance between c and M, we apply a Bayesian method to improve the statistical analysis of the c-M relation. It is shown that this new method allows us to derive the c-M relation with significantly reduced biases.

  17. Effects of center offset and noise on weak-lensing derived concentration-mass relation of dark matter halos

    International Nuclear Information System (INIS)

    Du, Wei; Fan, Zuhui

    2014-01-01

    With the halo catalog from the Millennium Simulation, we analyze the weak-lensing measured density profiles for clusters of galaxies, paying attention to the determination of the concentration-mass (c-M) relation, which can be biased by the center offset, selection effect, and shape noise from intrinsic ellipticities of background galaxies. Several different methods of locating the center of a cluster from weak-lensing effects alone are explored. We find that, for intermediate redshift clusters, the highest peak from our newly proposed two-scale smoothing method applied to the reconstructed convergence field, first with a smoothing scale of 2' and then 0.'5, corresponds best to the true center. Assuming the parameterized Navarro-Frenk-White profile, we fit the reduced tangential shear signals around different centers identified by different methods. It is shown that, for the ensemble median values, a center offset larger than one scale radius r s can bias the derived mass and concentration significantly lower than the true values, especially for low-mass halos. However, the existence of noise can compensate for the offset effect and reduce the systematic bias, although the scatter of mass and concentration becomes considerably larger. Statistically, the bias effect of center offset on the c-M relation is insignificant if an appropriate center finding method is adopted. On the other hand, noise from intrinsic ellipticities can bias the c-M relation derived from a sample of weak-lensing analyzed clusters if a simple χ 2 fitting method is used. To properly account for the scatter and covariance between c and M, we apply a Bayesian method to improve the statistical analysis of the c-M relation. It is shown that this new method allows us to derive the c-M relation with significantly reduced biases.

  18. National-scale exposure prediction for long-term concentrations of particulate matter and nitrogen dioxide in South Korea.

    Science.gov (United States)

    Kim, Sun-Young; Song, Insang

    2017-07-01

    The limited spatial coverage of the air pollution data available from regulatory air quality monitoring networks hampers national-scale epidemiological studies of air pollution. The present study aimed to develop a national-scale exposure prediction model for estimating annual average concentrations of PM 10 and NO 2 at residences in South Korea using regulatory monitoring data for 2010. Using hourly measurements of PM 10 and NO 2 at 277 regulatory monitoring sites, we calculated the annual average concentrations at each site. We also computed 322 geographic variables in order to represent plausible local and regional pollution sources. Using these data, we developed universal kriging models, including three summary predictors estimated by partial least squares (PLS). The model performance was evaluated with fivefold cross-validation. In sensitivity analyses, we compared our approach with two alternative approaches, which added regional interactions and replaced the PLS predictors with up to ten selected variables. Finally, we predicted the annual average concentrations of PM 10 and NO 2 at 83,463 centroids of residential census output areas in South Korea to investigate the population exposure to these pollutants and to compare the exposure levels between monitored and unmonitored areas. The means of the annual average concentrations of PM 10 and NO 2 for 2010, across regulatory monitoring sites in South Korea, were 51.63 μg/m3 (SD = 8.58) and 25.64 ppb (11.05), respectively. The universal kriging exposure prediction models yielded cross-validated R 2 s of 0.45 and 0.82 for PM 10 and NO 2 , respectively. Compared to our model, the two alternative approaches gave consistent or worse performances. Population exposure levels in unmonitored areas were lower than in monitored areas. This is the first study that focused on developing a national-scale point wise exposure prediction approach in South Korea, which will allow national exposure assessments and

  19. Low correlation between household carbon monoxide and particulate matter concentrations from biomass-related pollution in three resource-poor settings

    Energy Technology Data Exchange (ETDEWEB)

    Klasen, Elizabeth M.; Wills, Beatriz [Division of Pulmonary and Critical Care, School of Medicine, Johns Hopkins University, Baltimore (United States); Naithani, Neha [Division of Pulmonary and Critical Care, School of Medicine, Johns Hopkins University, Baltimore (United States); Nepal Nutrition Intervention Project Sarlahi, Kathmandu (Nepal); Gilman, Robert H. [Program in Global Disease Epidemiology and Control, Bloomberg School of Public Health, Johns Hopkins University, Baltimore (United States); Tielsch, James M. [Department of Global Health, School of Public Health and Health Services, George Washington University, Washington DC (United States); Chiang, Marilu [Biomedical Research Unit, A.B. PRISMA, Lima (Peru); Khatry, Subarna [Nepal Nutrition Intervention Project Sarlahi, Kathmandu (Nepal); Breysse, Patrick N. [Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore (United States); Menya, Diana [School of Public Health, Moi University, Eldoret (Kenya); AMPATH (Academic Model Providing Access to Healthcare), Eldoret (Kenya); Apaka, Cosmas [AMPATH (Academic Model Providing Access to Healthcare), Eldoret (Kenya); Carter, E. Jane; Sherman, Charles B. [AMPATH (Academic Model Providing Access to Healthcare), Eldoret (Kenya); Division of Pulmonary Medicine, The Warren Alpert School of Medicine, Brown University, Providence (United States); Miranda, J. Jaime [CRONICAS Center of Excellence in Chronic Diseases, Universidad Peruana Cayetano Heredia, Lima (Peru); Checkley, William, E-mail: wcheckl1@jhmi.edu [Division of Pulmonary and Critical Care, School of Medicine, Johns Hopkins University, Baltimore (United States); Program in Global Disease Epidemiology and Control, Bloomberg School of Public Health, Johns Hopkins University, Baltimore (United States); CRONICAS Center of Excellence in Chronic Diseases, Universidad Peruana Cayetano Heredia, Lima (Peru)

    2015-10-15

    Household air pollution from the burning of biomass fuels is recognized as the third greatest contributor to the global burden of disease. Incomplete combustion of biomass fuels releases a complex mixture of carbon monoxide (CO), particulate matter (PM) and other toxins into the household environment. Some investigators have used indoor CO concentrations as a reliable surrogate of indoor PM concentrations; however, the assumption that indoor CO concentration is a reasonable proxy of indoor PM concentration has been a subject of controversy. We sought to describe the relationship between indoor PM{sub 2.5} and CO concentrations in 128 households across three resource-poor settings in Peru, Nepal, and Kenya. We simultaneously collected minute-to-minute PM{sub 2.5} and CO concentrations within a meter of the open-fire stove for approximately 24 h using the EasyLog-USB-CO data logger (Lascar Electronics, Erie, PA) and the personal DataRAM-1000AN (Thermo Fisher Scientific Inc., Waltham, MA), respectively. We also collected information regarding household construction characteristics, and cooking practices of the primary cook. Average 24 h indoor PM{sub 2.5} and CO concentrations ranged between 615 and 1440 μg/m{sup 3}, and between 9.1 and 35.1 ppm, respectively. Minute-to-minute indoor PM{sub 2.5} concentrations were in a safe range (<25 μg/m{sup 3}) between 17% and 65% of the time, and exceeded 1000 μg/m{sup 3} between 8% and 21% of the time, whereas indoor CO concentrations were in a safe range (<7 ppm) between 46% and 79% of the time and exceeded 50 ppm between 4%, and 20% of the time. Overall correlations between indoor PM{sub 2.5} and CO concentrations were low to moderate (Spearman ρ between 0.59 and 0.83). There was also poor agreement and evidence of proportional bias between observed indoor PM{sub 2.5} concentrations vs. those estimated based on indoor CO concentrations, with greater discordance at lower concentrations. Our analysis does not support the

  20. Vertical profiles of lung deposited surface area concentration of particulate matter measured with a drone in a street canyon.

    Science.gov (United States)

    Kuuluvainen, Heino; Poikkimäki, Mikko; Järvinen, Anssi; Kuula, Joel; Irjala, Matti; Dal Maso, Miikka; Keskinen, Jorma; Timonen, Hilkka; Niemi, Jarkko V; Rönkkö, Topi

    2018-05-23

    The vertical profiles of lung deposited surface area (LDSA) concentration were measured in an urban street canyon in Helsinki, Finland, by using an unmanned aerial system (UAS) as a moving measurement platform. The street canyon can be classified as an avenue canyon with an aspect ratio of 0.45 and the UAS was a multirotor drone especially modified for emission measurements. In the experiments of this study, the drone was equipped with a small diffusion charge sensor capable of measuring the alveolar LDSA concentration of particles. The drone measurements were conducted during two days on the same spatial location at the kerbside of the street canyon by flying vertically from the ground level up to an altitude of 50 m clearly above the rooftop level (19 m) of the nearest buildings. The drone data were supported by simultaneous measurements and by a two-week period of measurements at nearby locations with various instruments. The results showed that the averaged LDSA concentrations decreased approximately from 60 μm 2 /cm 3 measured close to the ground level to 36-40 μm 2 /cm 3 measured close to the rooftop level of the street canyon, and further to 16-26 μm 2 /cm 3 measured at 50 m. The high-resolution measurement data enabled an accurate analysis of the functional form of vertical profiles both in the street canyon and above the rooftop level. In both of these regions, exponential fits were used and the parameters obtained from the fits were thoroughly compared to the values found in literature. The results of this study indicated that the role of turbulent mixing caused by traffic was emphasized compared to the street canyon vortex as a driving force of the dispersion. In addition, the vertical profiles above the rooftop level showed a similar exponential decay compared to the profiles measured inside the street canyon. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Significance of Isotopically Labile Organic Hydrogen in Thermal Maturation of Organic Matter

    Energy Technology Data Exchange (ETDEWEB)

    Arndt Schimmelmann; Maria Mastalerz

    2010-03-30

    Isotopically labile organic hydrogen in fossil fuels occupies chemical positions that participate in isotopic exchange and in chemical reactions during thermal maturation from kerogen to bitumen, oil and gas. Carbon-bound organic hydrogen is isotopically far less exchangeable than hydrogen bound to nitrogen, oxygen, or sulfur. We explore why organic hydrogen isotope ratios express a relationship with organic nitrogen isotope ratios in kerogen at low to moderate maturity. We develop and apply new techniques to utilize organic D/H ratios in organic matter fractions and on a molecular level as tools for exploration for fossil fuels and for paleoenvironmental research. The scope of our samples includes naturally and artificially matured substrates, such as coal, shale, oil and gas.

  2. Do causal concentration-response functions exist? A critical review of associational and causal relations between fine particulate matter and mortality.

    Science.gov (United States)

    Cox, Louis Anthony Tony

    2017-08-01

    Concentration-response (C-R) functions relating concentrations of pollutants in ambient air to mortality risks or other adverse health effects provide the basis for many public health risk assessments, benefits estimates for clean air regulations, and recommendations for revisions to existing air quality standards. The assumption that C-R functions relating levels of exposure and levels of response estimated from historical data usefully predict how future changes in concentrations would change risks has seldom been carefully tested. This paper critically reviews literature on C-R functions for fine particulate matter (PM2.5) and mortality risks. We find that most of them describe historical associations rather than valid causal models for predicting effects of interventions that change concentrations. The few papers that explicitly attempt to model causality rely on unverified modeling assumptions, casting doubt on their predictions about effects of interventions. A large literature on modern causal inference algorithms for observational data has been little used in C-R modeling. Applying these methods to publicly available data from Boston and the South Coast Air Quality Management District around Los Angeles shows that C-R functions estimated for one do not hold for the other. Changes in month-specific PM2.5 concentrations from one year to the next do not help to predict corresponding changes in average elderly mortality rates in either location. Thus, the assumption that estimated C-R relations predict effects of pollution-reducing interventions may not be true. Better causal modeling methods are needed to better predict how reducing air pollution would affect public health.

  3. Regional grey matter volume and concentration in at-risk adolescents: Untangling associations with callous-unemotional traits and conduct disorder symptoms.

    Science.gov (United States)

    Cohn, Moran D; Viding, Essi; McCrory, Eamon; Pape, Louise; van den Brink, Wim; Doreleijers, Theo A H; Veltman, Dick J; Popma, Arne

    2016-08-30

    Structural Magnetic Resonance Imaging studies have reported volume reductions in several brain regions implicated in social cognition and emotion recognition in juvenile antisocial populations. However, it is unclear whether these structural abnormalities are specifically related to antisocial features, or to co-occurring callous-unemotional (CU) traits. The present study employed voxel-based morphometry to assess both grey matter volume (GMV) and grey matter concentration (GMC) in a large representative at-risk sample of adolescents (n=134; mean age 17.7yr), characterized by a broad range of CU trait and conduct disorder (CD) symptom scores. There was a significant interaction between CD symptom and CU trait scores in the prediction of GMV in the anterior insula, with a significant positive association between CU traits and GMV in youth low on CD symptoms only. In addition, we found a significant unique positive association between CD symptoms and GMC in the amygdala, and unique negative associations between CU traits and GMC in the amygdala and insula. These findings are in line with accumulating evidence of distinct associations of CD symptoms and CU traits with amygdala and insula GMC in juvenile antisocial populations. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  4. A new method to radiolabel fulvic acids with tritium for the purpose of tracing organic matter transport at low concentrations

    International Nuclear Information System (INIS)

    Tinnacher, R.M.; Honeyman, B.D.; Leenheer, J.A.

    2005-01-01

    Full text of publication follows: It is increasingly evident that reactive transport models for radionuclides need to include the effects of natural organic ligands, such as bacterial exudates and humic and fulvic acids. Understanding the role of such ligands in radionuclide transport requires an ability to track ligand concentrations in time and space with an analytical resolution similar to that of the target radionuclide. Unfortunately, for many systems of interest for radioactive waste disposal and performance assessment, organic ligand concentrations are quite low (e.g., mg C/ L or less). Radiolabeling organic ligands can provide a means of tracing such species at low levels and for relatively low cost. Currently-used labeling methods, however, show some limitations with respect to the chemical stability of the radiolabel, the ability to produce high label specific activities and method reproducibility. In the procedure that we will describe, fulvic acid is radiolabeled with tritium by its reduction with tritiated sodium borohydride (NaBH 4 ) at alkaline pH and slightly elevated temperatures. The reactant selectively reduces the carbonyl groups of aromatic and aliphatic ketones as well as quinones. This results in the formation of tritium-labeled secondary alcohols. After completion of the labeling reaction, aerobically unstable reduction products of quinones and aromatic ketones are re-oxidized under controlled experimental conditions during an aeration step. Labeling efficiency in terms of reduced reactive fulvic acid groups is in the range of 100 percent with equal weights of fulvic acid and NaBH 4 in the reaction solution. This yields specific activities on the order of 50 to 100 μCi / mg fulvic acid. A quasi-chemical model of the labeling process allows the accurate prediction of the labeling efficiency based on a simplified mass action expression for the labeling reaction and the mass balance equations for fulvic acid and sodium borohydride. Such a

  5. Fine-scale estimation of carbon monoxide and fine particulate matter concentrations in proximity to a road intersection by using wavelet neural network with genetic algorithm

    Science.gov (United States)

    Wang, Zhanyong; Lu, Feng; He, Hong-di; Lu, Qing-Chang; Wang, Dongsheng; Peng, Zhong-Ren

    2015-03-01

    At road intersections, vehicles frequently stop with idling engines during the red-light period and speed up rapidly in the green-light period, which generates higher velocity fluctuation and thus higher emission rates. Additionally, the frequent changes of wind direction further add the highly variable dispersion of pollutants at the street scale. It is, therefore, very difficult to estimate the distribution of pollutant concentrations using conventional deterministic causal models. For this reason, a hybrid model combining wavelet neural network and genetic algorithm (GA-WNN) is proposed for predicting 5-min series of carbon monoxide (CO) and fine particulate matter (PM2.5) concentrations in proximity to an intersection. The proposed model is examined based on the measured data under two situations. As the measured pollutant concentrations are found to be dependent on the distance to the intersection, the model is evaluated in three locations respectively, i.e. 110 m, 330 m and 500 m. Due to the different variation of pollutant concentrations on varied time, the model is also evaluated in peak and off-peak traffic time periods separately. Additionally, the proposed model, together with the back-propagation neural network (BPNN), is examined with the measured data in these situations. The proposed model is found to perform better in predictability and precision for both CO and PM2.5 than BPNN does, implying that the hybrid model can be an effective tool to improve the accuracy of estimating pollutants' distribution pattern at intersections. The outputs of these findings demonstrate the potential of the proposed model to be applicable to forecast the distribution pattern of air pollution in real-time in proximity to road intersection.

  6. Determination of heavy metals concentrations in airborne particulates matter (APM) from Manjung district, Perak using energy dispersive X-ray fluorescence (EDXRF) spectrometer

    Science.gov (United States)

    Arshad, Nursyairah; Hamzah, Zaini; Wood, Ab. Khalik; Saat, Ahmad; Alias, Masitah

    2015-04-01

    Airborne particulates trace metals are considered as public health concern as it can enter human lungs through respiratory system. Generally, any substance that has been introduced to the atmosphere that can cause severe effects to living things and the environment is considered air pollution. Manjung, Perak is one of the development districts that is active with industrial activities. There are many industrial activities surrounding Manjung District area such as coal fired power plant, quarries and iron smelting which may contribute to the air pollution into the environment. This study was done to measure the concentrations of Hg, U, Th, K, Cu, Fe, Cr, Zn, As, Se, Pb and Cd in the Airborne Particulate Matter (APM) collected at nine locations in Manjung District area within 15 km radius towards three directions (North, North-East and South-East) in 5 km intervals. The samples were collected using mini volume air sampler with cellulose filter through total suspended particulate (TSP). The sampler was set up for eight hours with the flow rate of 5 L/min. The filter was weighed before and after sample collection using microbalance, to get the amount of APM and kept in desiccator before analyzing. The measurement was done using calibrated Energy Dispersive X-Ray Fluorescence (EDXRF) Spectrometer. The air particulate concentrations were found below the Malaysia Air Quality Guidelines for TSP (260 µg/m3). All of the metals concentrations were also lower than the guidelines set by World Health Organization (WHO), Ontario Ministry of the Environment and Argonne National Laboratory, USA NCRP (1975). From the concentrations, the enrichment factor were calculated.

  7. Short-term population-based non-linear concentration-response associations between fine particulate matter and respiratory diseases in Taipei (Taiwan): a spatiotemporal analysis.

    Science.gov (United States)

    Yu, Hwa-Lung; Chien, Lung-Chang

    2016-01-01

    Fine particulate matter respiratory disease remain inconsistent. The short-term, population-based association between the respiratory clinic visits of children and PM2.5 exposure levels were investigated by considering both the spatiotemporal distributions of ambient pollution and clinic visit data. We applied a spatiotemporal structured additive regression model to examine the concentration-response (C-R) association between children's respiratory clinic visits and PM2.5 concentrations. This analysis was separately performed on three respiratory disease categories that were selected from the Taiwanese National Health Insurance database, which includes 41 districts in the Taipei area of Taiwan from 2005 to 2007. The findings reveal a non-linear C-R pattern of PM2.5, particularly in acute respiratory infections. However, a PM2.5 increase at relatively lower levels can elevate the same-day respiratory health risks of both preschool children (increase from 0.76 to 7.44 μg/m(3), and in schoolchildren, same-day health risks rise when concentrations increase from 0.76 to 7.52 μg/m(3). Changes in PM2.5 levels generally exhibited no significant association with same-day respiratory risks, except in instances where PM2.5 levels are extremely high, and these occurrences do exhibit a significant positive influence on respiratory health that is especially notable in schoolchildren. A significant high relative rate of respiratory clinic visits are concentrated in highly populated areas. We highlight the non-linearity of the respiratory health effects of PM2.5 on children to investigate this population-based association. The C-R relationship in this study can provide a highly valuable alternative for assessing the effects of ambient air pollution on human health.

  8. Temporal Dynamics in the Concentration, Flux, and Optical Properties of Tree-Derived Dissolved Organic Matter in an Epiphyte-Laden Oak-Cedar Forest

    Science.gov (United States)

    Van Stan, John T.; Wagner, Sasha; Guillemette, François; Whitetree, Ansley; Lewis, Julius; Silva, Leticia; Stubbins, Aron

    2017-11-01

    Studies on the fate and transport of dissolved organic matter (DOM) along the rainfall-to-discharge flow pathway typically begin in streams or soils, neglecting the initial enrichment of rainfall with DOM during contact with plant canopies. However, rain water can gather significant amounts of tree-derived DOM (tree-DOM) when it drains from the canopy, as throughfall, and down the stem, as stemflow. We examined the temporal variability of event-scale tree-DOM concentrations, yield, and optical (light absorbance and fluorescence) characteristics from an epiphyte-laden Quercus virginiana-Juniperus virginiana forest on Skidaway Island, Savannah, Georgia (USA). All tree-DOM fluxes were highly enriched in dissolved organic carbon (DOC) compared to rainfall, and epiphytes further increased concentrations. Stemflow DOC concentrations were greater than throughfall across study species, yet larger throughfall water yields produced greater DOC yields versus stemflow. Tree-DOM optical characteristics indicate it is aromatic-rich with fluorescent DOM dominated by humic-like fluorescence, containing 10-20% protein-like (tryptophan-like) fluorescence. Storm size was the only storm condition that strongly correlated with tree-DOM concentration and flux; however, throughfall and stemflow optical characteristics varied little across a wide range of storm conditions (from low magnitude events to intense tropical storms). Annual tree-DOM yields from the study forest (0.8-46 g C m-2 yr-1) were similar to other yields from discrete down-gradient fluxes (litter leachates, soil leachates, and stream discharge) along the rainfall-to-discharge flow path.

  9. The Effects of Arbuscular Mycorrhiza Fungi on Dry Matter and Concentrations of Nitrogen, Phosphorus and Potassium in Berseem Clover, by Cadmium stress

    Directory of Open Access Journals (Sweden)

    hashem aram

    2016-02-01

    Zanjan, after the complete analysis of soil and obtaining the chemical and physical properties in the laboratory. 6 kg of soil was weighed for each pot and then the soil was contaminated. Cadmium sulfate was used in this experiment. The mycorrhizal fungi weighed 150 grams and was mixed with the soil. After mixing the soil with mycorrhizal fungi, the soil was put in pots and then it was cultivated with clover. In this study, clover seeds weighed 0/5 grams and were disinfected with 10% hydrogen peroxide solution and were added to each pot. Distilled water was used for irrigation. After the completion of growth of plants (about 70 day, plant aerial parts and roots were harvested and before measuring, they were washed with distilled water and then were dried in the oven for 72 hours. Plant aerial parts were harvested. Data were analyzed by SAS (version 9 and MSTATC (version 2.10 software, and obtained variance analysis tables. Mean comparison of different treatments was conducted by Duncan test. Charts were obtained by excel software. Results and Discussion: The results showed that the effects of arbuscular mycorrhizal fungi were significant on all traits measured (P< 0.01. With increasing cadmium concentration in soil, dry matter of 37% and 39%, nitrogen concentration of 35% and 28%, Potassium 9/27% and 37%, and phosphorus concentration of 37% and 39%, reduced in root and aerial, respectively. Also the results showed that arbuscular mycorrhizal fungi increased dry matter amount by 42% and 26%, nitrogen concentration by 40.3% and 30%, phosphorus concentration by 6% and 15.4%, potassium concentrations by 54% and 91.2% in root and aerial, respectively. Interaction between cadmium levels and mycorrhizal fungi in statistics was significant on dry matter aerial, nitrogen concentration in aerial and root, and potassium concentrations in plant root (P< 0.01. Conclusion: The results showed that mycorrhizal fungi were significant on all traits measured in one percent level. Cadmium

  10. Représentation chimique de la structure des kérogènes et des asphaltènes en fonction de leur origine et de leur degré d'évolution Chemical Modeling of the Structure of Kerogens and Asphaltenes As a Function of Their Origin and Evolution Stage

    Directory of Open Access Journals (Sweden)

    Behar F.

    2006-11-01

    Full Text Available Dans cet article nous proposons des modèles de structures chimiques de kérogènes et d'asphaltènes de roche. Nous avons choisi de représenter les kérogènes appartenant aux trois types classiques de matières organiques aux stades d'évolution suivants : - début de la diagenèse sensu-stricto; - début de la catagenèse (formation de l'huile; - fin de la catagenèse (formation du gaz. Les asphaltènes représentés correspondent à la phase de formation de l'huile. Nous avons tenu compte des données d'analyse obtenues sur des échantillons naturels : analyse élémentaire, microscopie électronique, RMN 13C, thermogravimétrie, analyse fonctionnelle, dégradation par pyrolyse. Afin d'obtenir une représentation chimique ayant une valeur statistique suffisante, nous avons choisi une masse moléculaire de 25 000 environ, identique pour les trois kérogènes au début de la diagenèse, et une masse de 8000 environ pour les asphaltènes associés. Nous avons ensuite dessiné à l'échelle moléculaire les structures correspondantes. This paper proposes models for the chemical structures of kerogens and asphaltenes from rocks. The kerogens belonging to the three conventional types of organic matter are represented in the following stages of evolution: (1 beginning of diagenesis sensu stricto,(2 beginning of catagenesis (formation of oil, and (3 end of catagenesis (formation of gas. The asphaltenes represented here correspond to the phase of oil formation. Models are based on analytical data obtained on natural samples, i. e. elemental analysis, electron microscopy, 13C NMR, thermogravimetry, functional analysis and pyrolysis. To get enough statistical value for the chemical modelling, a same molecular mass of about 25 000 was chosen for the three kerogens at the beginning of diagenesis. A molecular mass of about 8000 was chosen for the related asphaltenes. The chemical structures were then constructed at the molecular scale.

  11. A New Hybrid Model FPA-SVM Considering Cointegration for Particular Matter Concentration Forecasting: A Case Study of Kunming and Yuxi, China.

    Science.gov (United States)

    Li, Weide; Kong, Demeng; Wu, Jinran

    2017-01-01

    Air pollution in China is becoming more serious especially for the particular matter (PM) because of rapid economic growth and fast expansion of urbanization. To solve the growing environment problems, daily PM2.5 and PM10 concentration data form January 1, 2015, to August 23, 2016, in Kunming and Yuxi (two important cities in Yunnan Province, China) are used to present a new hybrid model CI-FPA-SVM to forecast air PM2.5 and PM10 concentration in this paper. The proposed model involves two parts. Firstly, due to its deficiency to assess the possible correlation between different variables, the cointegration theory is introduced to get the input-output relationship and then obtain the nonlinear dynamical system with support vector machine (SVM), in which the parameters c and g are optimized by flower pollination algorithm (FPA). Six benchmark models, including FPA-SVM, CI-SVM, CI-GA-SVM, CI-PSO-SVM, CI-FPA-NN, and multiple linear regression model, are considered to verify the superiority of the proposed hybrid model. The empirical study results demonstrate that the proposed model CI-FPA-SVM is remarkably superior to all considered benchmark models for its high prediction accuracy, and the application of the model for forecasting can give effective monitoring and management of further air quality.

  12. A New Hybrid Model FPA-SVM Considering Cointegration for Particular Matter Concentration Forecasting: A Case Study of Kunming and Yuxi, China

    Directory of Open Access Journals (Sweden)

    Weide Li

    2017-01-01

    Full Text Available Air pollution in China is becoming more serious especially for the particular matter (PM because of rapid economic growth and fast expansion of urbanization. To solve the growing environment problems, daily PM2.5 and PM10 concentration data form January 1, 2015, to August 23, 2016, in Kunming and Yuxi (two important cities in Yunnan Province, China are used to present a new hybrid model CI-FPA-SVM to forecast air PM2.5 and PM10 concentration in this paper. The proposed model involves two parts. Firstly, due to its deficiency to assess the possible correlation between different variables, the cointegration theory is introduced to get the input-output relationship and then obtain the nonlinear dynamical system with support vector machine (SVM, in which the parameters c and g are optimized by flower pollination algorithm (FPA. Six benchmark models, including FPA-SVM, CI-SVM, CI-GA-SVM, CI-PSO-SVM, CI-FPA-NN, and multiple linear regression model, are considered to verify the superiority of the proposed hybrid model. The empirical study results demonstrate that the proposed model CI-FPA-SVM is remarkably superior to all considered benchmark models for its high prediction accuracy, and the application of the model for forecasting can give effective monitoring and management of further air quality.

  13. Constraining dark matter halo profiles and galaxy formation models using spiral arm morphology. II. Dark and stellar mass concentrations for 13 nearby face-on galaxies

    International Nuclear Information System (INIS)

    Seigar, Marc S.; Davis, Benjamin L.; Berrier, Joel; Kennefick, Daniel

    2014-01-01

    We investigate the use of spiral arm pitch angles as a probe of disk galaxy mass profiles. We confirm our previous result that spiral arm pitch angles (P) are well correlated with the rate of shear (S) in disk galaxy rotation curves. We use this correlation to argue that imaging data alone can provide a powerful probe of galactic mass distributions out to large look-back times. We then use a sample of 13 galaxies, with Spitzer 3.6 μm imaging data and observed Hα rotation curves, to demonstrate how an inferred shear rate coupled with a bulge-disk decomposition model and a Tully-Fisher-derived velocity normalization can be used to place constraints on a galaxy's baryon fraction and dark matter halo profile. Finally, we show that there appears to be a trend (albeit a weak correlation) between spiral arm pitch angle and halo concentration. We discuss implications for the suggested link between supermassive black hole (SMBH) mass and dark halo concentration, using pitch angle as a proxy for SMBH mass.

  14. Long-term particulate matter modeling for health effect studies in California - Part 2: Concentrations and sources of ultrafine organic aerosols

    Science.gov (United States)

    Hu, Jianlin; Jathar, Shantanu; Zhang, Hongliang; Ying, Qi; Chen, Shu-Hua; Cappa, Christopher D.; Kleeman, Michael J.

    2017-04-01

    Organic aerosol (OA) is a major constituent of ultrafine particulate matter (PM0. 1). Recent epidemiological studies have identified associations between PM0. 1 OA and premature mortality and low birth weight. In this study, the source-oriented UCD/CIT model was used to simulate the concentrations and sources of primary organic aerosols (POA) and secondary organic aerosols (SOA) in PM0. 1 in California for a 9-year (2000-2008) modeling period with 4 km horizontal resolution to provide more insights about PM0. 1 OA for health effect studies. As a related quality control, predicted monthly average concentrations of fine particulate matter (PM2. 5) total organic carbon at six major urban sites had mean fractional bias of -0.31 to 0.19 and mean fractional errors of 0.4 to 0.59. The predicted ratio of PM2. 5 SOA / OA was lower than estimates derived from chemical mass balance (CMB) calculations by a factor of 2-3, which suggests the potential effects of processes such as POA volatility, additional SOA formation mechanism, and missing sources. OA in PM0. 1, the focus size fraction of this study, is dominated by POA. Wood smoke is found to be the single biggest source of PM0. 1 OA in winter in California, while meat cooking, mobile emissions (gasoline and diesel engines), and other anthropogenic sources (mainly solvent usage and waste disposal) are the most important sources in summer. Biogenic emissions are predicted to be the largest PM0. 1 SOA source, followed by mobile sources and other anthropogenic sources, but these rankings are sensitive to the SOA model used in the calculation. Air pollution control programs aiming to reduce the PM0. 1 OA concentrations should consider controlling solvent usage, waste disposal, and mobile emissions in California, but these findings should be revisited after the latest science is incorporated into the SOA exposure calculations. The spatial distributions of SOA associated with different sources are not sensitive to the choice of

  15. The soil organic carbon content of anthropogenically altered organic soils effects the dissolved organic matter quality, but not the dissolved organic carbon concentrations

    Science.gov (United States)

    Frank, Stefan; Tiemeyer, Bärbel; Bechtold, Michel; Lücke, Andreas; Bol, Roland

    2016-04-01

    Dissolved organic carbon (DOC) is an important link between terrestrial and aquatic ecosystems. This is especially true for peatlands which usually show high concentrations of DOC due to the high stocks of soil organic carbon (SOC). Most previous studies found that DOC concentrations in the soil solution depend on the SOC content. Thus, one would expect low DOC concentrations in peatlands which have anthropogenically been altered by mixing with sand. Here, we want to show the effect of SOC and groundwater level on the quantity and quality of the dissolved organic matter (DOM). Three sampling sites were installed in a strongly disturbed bog. Two sites differ in SOC (Site A: 48%, Site B: 9%) but show the same mean annual groundwater level of 15 and 18 cm below ground, respectively. The SOC content of site C (11%) is similar to Site B, but the groundwater level is much lower (-31 cm) than at the other two sites. All sites have a similar depth of the organic horizon (30 cm) and the same land-use (low-intensity sheep grazing). Over two years, the soil solution was sampled bi-weekly in three depths (15, 30 and 60 cm) and three replicates. All samples were analyzed for DOC and selected samples for dissolved organic nitrogen (DON) and delta-13C and delta-15N. Despite differences in SOC and groundwater level, DOC concentrations did not differ significantly (A: 192 ± 62 mg/L, B: 163 ± 55 mg/L and C: 191 ± 97 mg/L). At all sites, DOC concentrations exceed typical values for peatlands by far and emphasize the relevance even of strongly disturbed organic soils for DOC losses. Individual DOC concentrations were controlled by the temperature and the groundwater level over the preceding weeks. Differences in DOM quality were clearer. At site B with a low SOC content, the DOC:DON ratio of the soil solution equals the soil's C:N ratio, but the DOC:DON ratio is much higher than the C:N ratio at site A. In all cases, the DOC:DON ratio strongly correlates with delta-13C. There is no

  16. Effect of biomass open burning on particulate matter and polycyclic aromatic hydrocarbon concentration levels and PAH dry deposition in ambient air.

    Science.gov (United States)

    Chiu, Jui C; Shen, Yun H; Li, Hsing W; Chang, Shun S; Wang, Lin C; Chang-Chien, Guo P

    2011-01-01

    The objectives of the present study were to investigate particulate matter (PM) and polycyclic aromatic hydrocarbon (PAH) concentrations in ambient air during rice straw open burning and non-open burning periods. In the ambient air of a rice field, the mean PM concentration during and after an open burning event were 1828 and 102 μg m⁻³, respectively, which demonstrates that during a rice field open burning event, the PM concentration in the ambient air of rice field is over 17 times higher than that of the non-open burning period. During an open burning event, the mean total PAH and total toxic equivalence (BaP(eq)) concentrations in the ambient air of a rice field were 7206 ng m⁻³ and 10.3 ng m⁻³, respectively, whereas after the open burning event, they were 376 ng m⁻³ and 1.50 ng m⁻³, respectively. Open burning thus increases total PAH and total BaP(eq) concentrations by 19-fold and 6.8-fold, respectively. During a rice straw open burning event, in the ambient air of a rice field, the mean dry deposition fluxes of total PAHs and total BaP(eq) were 1222 μg m⁻² day⁻¹ and 4.80 μg m⁻² day⁻¹, respectively, which are approximately 60- and 3-fold higher than those during the non-open burning period, respectively. During the non-open burning period, particle-bound PAHs contributed 79.2-84.2% of total dry deposition fluxes (gas + particle) of total PAHs. However, an open burning event increases the contribution to total PAH dry deposition by particle-bound PAHs by up to 85.9-95.5%. The results show that due to the increased amount of PM in the ambient air resulting from rice straw open burning, particle-bound PAHs contributed more to dry deposition fluxes of total PAHs than they do during non-open burning periods. The results show that biomass (rice straw) open burning is an important PAH emission source that significantly increases both PM and PAH concentration levels and PAH dry deposition in ambient air.

  17. Concentrations and Size Distributions of Trace Metals in Particulate Matter in Urban New Jersey: Preliminary Results from the Newly Established Rutgers Newark Urban Air Quality Observatory.

    Science.gov (United States)

    Rabinovich, O.; Gao, Y.

    2017-12-01

    Particulate air pollution has been associated with health issues in general and respiratory diseases in particular. Some research has shown that higher concentration of fine particulate matter (PM) is found in lungs. However, why and what kind of PM plays the roles affecting the human health still need more investigations, and most of previous and current studies were limited to those focusing on PM2.5 or larger particles. The city of Newark in New Jersey is the largest metropolitan center in the state with dense population; it is a commerce and transportation hub surrounded by many highways and busy airports, in addition to numerous power plants, waste combustion treatment facilities, etc. in the area. Thus, the city is impacted by air pollution emissions In some areas of the city, the elevated records of respiratory illness were reported. Although some PM2.5 concentration studies were done in the past, the enrichment of toxic metals in PM with respect to their sizes have not been fully addressed. The Rutgers Newark Air Quality Observatory (RNAQO) was recently established to address urban air pollution and its impact on human health. During this study, both size-segregated PM and PM2.5 are collected in RNAQO, Newark, New Jersey. The samples are analyzed to evaluate the enrichment of trace metals focusing on Pb, Cd, Cu, and Zn in different sizes of PM that will be discussed in this presentation. Such data will be valuable to further investigations into the health effects of fine mode PM. Particularly, this data will be helpful in exploring the relationships between respiratory sickness and fine mode toxic metals' concentrations.

  18. Regional contributions to particulate matter concentration in the Seoul metropolitan area, South Korea: seasonal variation and sensitivity to meteorology and emissions inventory

    Science.gov (United States)

    Kim, Hyun Cheol; Kim, Eunhye; Bae, Changhan; Cho, Jeong Hoon; Kim, Byeong-Uk; Kim, Soontae

    2017-09-01

    The impact of regional emissions (e.g., domestic and international) on surface particulate matter (PM) concentrations in the Seoul metropolitan area (SMA), South Korea, and its sensitivities to meteorology and emissions inventories are quantitatively estimated for 2014 using regional air quality modeling systems. Located on the downwind side of strong sources of anthropogenic emissions, South Korea bears the full impact of the regional transport of pollutants and their precursors. However, the impact of foreign emissions sources has not yet been fully documented. We utilized two regional air quality simulation systems: (1) a Weather Research and Forecasting and Community Multi-Scale Air Quality (CMAQ) system and (2) a United Kingdom Met Office Unified Model and CMAQ system. The following combinations of emissions inventories are used: the Intercontinental Chemical Transport Experiment-Phase B, the Inter-comparison Study for Asia 2010, and the National Institute of Environment Research Clean Air Policy Support System. Partial contributions of domestic and foreign emissions are estimated using a brute force approach, adjusting South Korean emissions to 50 %. Results show that foreign emissions contributed ˜ 60 % of SMA surface PM concentration in 2014. Estimated contributions display clear seasonal variation, with foreign emissions having a higher impact during the cold season (fall to spring), reaching ˜ 70 % in March, and making lower contributions in the summer, ˜ 45 % in September. We also found that simulated surface PM concentration is sensitive to meteorology, but estimated contributions are mostly consistent. Regional contributions are also found to be sensitive to the choice of emissions inventories.

  19. Aggregation and ecotoxicity of CeO{sub 2} nanoparticles in synthetic and natural waters with variable pH, organic matter concentration and ionic strength

    Energy Technology Data Exchange (ETDEWEB)

    Van Hoecke, Karen, E-mail: karen.vanhoecke@ugent.be [Laboratory of Environmental Toxicology and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Jozef Plateaustraat 22, B-9000 Gent (Belgium); De Schamphelaere, Karel A.C. [Laboratory of Environmental Toxicology and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Jozef Plateaustraat 22, B-9000 Gent (Belgium); Van der Meeren, Paul [Particle and Interfacial Technology Group, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Gent (Belgium); Smagghe, Guy [Laboratory of Agrozoology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Gent (Belgium); Janssen, Colin R. [Laboratory of Environmental Toxicology and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Jozef Plateaustraat 22, B-9000 Gent (Belgium)

    2011-04-15

    The influence of pH (6.0-9.0), natural organic matter (NOM) (0-10 mg C/L) and ionic strength (IS) (1.7-40 mM) on 14 nm CeO{sub 2} NP aggregation and ecotoxicity towards the alga Pseudokirchneriella subcapitata was assessed following a central composite design. Mean NP aggregate sizes ranged between 200 and 10000 nm. Increasing pH and IS enhanced aggregation, while increasing NOM decreased mean aggregate sizes. The 48 h-E{sub r}C20s ranged between 4.7 and 395.8 mg CeO{sub 2}/L. An equation for predicting the 48 h-E{sub r}C20 (48 h-E{sub r}C20 = -1626.4 x (pH) + 109.45 x (pH){sup 2} + 116.49 x ([NOM]) - 14.317 x (pH) x ([NOM]) + 6007.2) was developed. In a validation study with natural waters the predicted 48 h-E{sub r}C20 was a factor 1.08-2.57 lower compared to the experimental values. - Research highlights: > Algal ecotoxicity of CeO{sub 2} nanoparticles (NPs) depends on pH and NOM concentration. > Increasing pH and ionic strength enhanced CeO{sub 2} nanoparticle aggregation. > Increasing NOM concentration decreased mean CeO{sub 2} aggregate size. > An empirical model to predict 48 h-E{sub r}C{sub 20} values of CeO{sub 2} NPs was developed. > The model was validated using natural surface waters with various characteristics. - CeO{sub 2} nanoparticle aggregation and toxicity depend on abiotic factors such as pH, NOM and IS. Effect concentrations can be predicted as a function of pH and NOM.

  20. The effect of feeding bull Bali cattle kept in extensive husbandry system with concentrates contained gliricidia sepium leaf meal and banana strach tuber meal on their feed consumption and dried organic matter digestability

    Science.gov (United States)

    Fattah, S.; Sobang, Y. U. L.; Samba, F. D.; Hartati, E.; Kapa, M. M. J.; Henuk, Y. L.

    2018-02-01

    This study aimed to evaluate the effect of feeding bull Bali Cattle kept in extensive husbnadry system with concentrates contained gliricidia sepium leaf meal and banana strach tuber meal in their feed consumptions and dried organic matter digestibility. Three bull Bali cattle aged 1 - 2 years old with an initial body weight of 135.5 kg - 168.0 kg were used in this study. The three treatments used were T0 = local feeds (consisted of Leucaena leucocephala, Acasia leochophloea, and Ficus sp. leaves as commonly used by local farmers); T1 = T0 + 1 kg concentrate (contained banana strach tuber meal + gliricidia sepium leaf meal); T2 = T1 +2 kg concentrate (contained banana strach tuber meal + gliricidia sepium leaf meal). The results showed that the dry matter intake were: 2.40, 3.52, and 4.14; organic matter intake were: 2.17, 3.32, and 3.62; dry matter digestible was 64.63%, 72.45%, 77.28% and organic matter digestible was 66.79%, 74.66%, 79.33% for T0, T1, and T2, respectively. There was no effect (P>0.05) of treatments on the three parameters observed on bull Bali cattle kept in extensive husbandry system and fed with concentrates contained leaf gliricidia sepium meal and banana starch tuber meal.

  1. Investigation of time-resolved atmospheric conditions and indoor/outdoor particulate matter concentrations in homes with gas and biomass cook stoves in Nogales, Sonora, Mexico.

    Science.gov (United States)

    Holmes, Heather A; Pardyjak, Eric R

    2014-07-01

    This paper reports findings from a case study designed to investigate indoor and outdoor air quality in homes near the United States-Mexico border During the field study, size-resolved continuous particulate matter (PM) concentrations were measured in six homes, while outdoor PM was simultaneously monitored at the same location in Nogales, Sonora, Mexico, during March 14-30, 2009. The purpose of the experiment was to compare PM in homes using different fuels for cooking, gas versus biomass, and to obtain a spatial distribution of outdoor PM in a region where local sources vary significantly (e.g., highway, border crossing, unpaved roads, industry). Continuous PM data were collected every 6 seconds using a valve switching system to sample indoor and outdoor air at each home location. This paper presents the indoor PM data from each home, including the relationship between indoor and outdoor PM. The meteorological conditions associated with elevated ambient PM events in the region are also discussed. Results indicate that indoor air pollution has a strong dependence on cooking fuel, with gas stoves having hourly averaged median PM3 concentrations in the range of 134 to 157 microg m(-3) and biomass stoves 163 to 504 microg m(-1). Outdoor PM also indicates a large spatial heterogeneity due to the presence of microscale sources and meteorological influences (median PM3: 130 to 770 microg m(-3)). The former is evident in the median and range of daytime PM values (median PM3: 250 microg m(-3), maximum: 9411 microg m(-3)), while the meteorological influences appear to be dominant during nighttime periods (median PM3: 251 microg m(-3), maximum: 10,846 microg m(-3)). The atmospheric stability is quantified for three nighttime temperature inversion episodes, which were associated with an order of magnitude increase in PM10 at the regulatory monitor in Nogales, AZ (maximum increase: 12 to 474 microg m(-3)). Implications: Regulatory air quality standards are based on outdoor

  2. Selective release of D and 13C from insoluble organic matter of the Murchison meteorite by impact shock

    Science.gov (United States)

    Mimura, Koichi; Okamoto, Michioki; Sugitani, Kenichiro; Hashimoto, Shigemasa

    2007-03-01

    We performed shock-recovery experiments on insoluble organic matter (IOM) purified from the Murchison meteorite, and determined the abundances and isotope ratios of hydrogen and carbon in the shocked IOM sample. We also performed shock experiments on type III kerogen and compared the results of these experiments with the experimental results regarding IOM.The shock selectively released D and 13C from the IOM, while it preferably released H and 12C from the kerogen. The release of these elements from IOM cannot be explained in terms of the isotope effect, whereas their release from kerogen can be explained by this effect. The selective release of heavier isotopes from IOM would be due to its structure, in which D and 13C-enriched parts are present as an inhomogeneity and are weakly attached to the main network. Shock gave rise to a high release of D even at a lower degree of dehydrogenation compared with the stepwise heating of IOM. This effective release of D is probably an inherent result of shock, in which a dynamic high-pressure and high-temperature condition prevails. Thus, shock would effectively control the hydrogen isotope behavior of extraterrestrial organic matter during the evolution of the solar nebula.

  3. Geospatial analysis of residential proximity to open-pit coal mining areas in relation to micronuclei frequency, particulate matter concentration, and elemental enrichment factors.

    Science.gov (United States)

    Espitia-Pérez, Lyda; Arteaga-Pertuz, Marcia; Soto, José Salvador; Espitia-Pérez, Pedro; Salcedo-Arteaga, Shirley; Pastor-Sierra, Karina; Galeano-Páez, Claudia; Brango, Hugo; da Silva, Juliana; Henriques, João A P

    2018-05-03

    During coal surface mining, several activities such as drilling, blasting, loading, and transport produce large quantities of particulate matter (PM) that is directly emitted into the atmosphere. Occupational exposure to this PM has been associated with an increase of DNA damage, but there is a scarcity of data examining the impact of these industrial operations in cytogenetic endpoints frequency and cancer risk of potentially exposed surrounding populations. In this study, we used a Geographic Information Systems (GIS) approach and Inverse Distance Weighting (IDW) methods to perform a spatial and statistical analysis to explore whether exposure to PM 2.5 and PM 10 pollution, and additional factors, including the enrichment of the PM with inorganic elements, contribute to cytogenetic damage in residents living in proximity to an open-pit coal mining area. Results showed a spatial relationship between exposure to elevated concentrations of PM 2.5, PM 10 and micronuclei frequency in binucleated (MNBN) and mononucleated (MNMONO) cells. Active pits, disposal, and storage areas could be identified as the possible emission sources of combustion elements. Mining activities were also correlated with increased concentrations of highly enriched elements like S, Cu and Cr in the atmosphere, corroborating its role in the inorganic elements pollution around coal mines. Elements enriched in the PM 2.5 fraction contributed to increasing of MNBN but seems to be more related to increased MNMONO frequencies and DNA damage accumulated in vivo. The combined use of GIS and IDW methods could represent an important tool for monitoring potential cancer risk associated to dynamically distributed variables like the PM. Copyright © 2018. Published by Elsevier Ltd.

  4. Comparison of dialysis and solid-phase extraction for isolation and concentration of dissolved organic matter prior to Fourier transform ion cyclotron resonance mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Tfaily, Malak M.; Cooper, William T. [Florida State University, Department of Chemistry and Biochemistry, Tallahassee, FL (United States); Hodgkins, Suzanne; Chanton, Jeffrey P. [Florida State University, Department of Earth, Ocean and Atmospheric Science, Tallahassee, FL (United States); Podgorski, David C. [Florida State University, Department of Chemistry and Biochemistry, Tallahassee, FL (United States); Florida State University, National High Magnetic Field Laboratory, Tallahassee, FL (United States)

    2012-08-15

    We compare two methods, solid-phase extraction (SPE) and dialysis, commonly used for extraction and concentration of dissolved organic matter (DOM) prior to molecular characterization by electrospray ionization (ESI) and ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry. Spectra of DOM samples from Minnesota and Sweden peatlands that were extracted with styrene divinyl benzene polymer SPE sorbents included ions with formulas that had higher oxygen to carbon (O/C) ratios than spectra of DOM from the same samples after de-salting by dialysis. The SPE method was not very effective in extracting several major classes of DOM compounds that had high ESI efficiencies, including carboxylic acids and organo-sulfur compounds, and that out-competed other less-functionalized compounds (e.g., carbohydrates) for charge in the ESI source. The large abundance of carboxylic acids in the dialysisextracted DOM, likely the result of in situ microbial production, makes it difficult to see other (mainly hydrophilic) compounds with high O/C ratios. Our results indicate that, while dialysis is generally preferable for the isolation of DOM, for samples with high microbial inputs, the use of both isolation methods is recommended for a more accurate molecular representation. (orig.)

  5. Retrieval of High-Resolution Atmospheric Particulate Matter Concentrations from Satellite-Based Aerosol Optical Thickness over the Pearl River Delta Area, China

    Directory of Open Access Journals (Sweden)

    Lili Li

    2015-06-01

    Full Text Available Satellite remote sensing offers an effective approach to estimate indicators of air quality on a large scale. It is critically significant for air quality monitoring in areas experiencing rapid urbanization and consequently severe air pollution, like the Pearl River Delta (PRD in China. This paper starts with examining ground observations of particulate matter (PM and the relationship between PM10 (particles smaller than 10 μm and aerosol optical thickness (AOT by analyzing observations on the sampling sites in the PRD. A linear regression (R2 = 0.51 is carried out using MODIS-derived 500 m-resolution AOT and PM10 concentration from monitoring stations. Data of atmospheric boundary layer (ABL height and relative humidity are used to make vertical and humidity corrections on AOT. Results after correction show higher correlations (R2 = 0.55 between extinction coefficient and PM10. However, coarse spatial resolution of meteorological data affects the smoothness of retrieved maps, which suggests high-resolution and accurate meteorological data are critical to increase retrieval accuracy of PM. Finally, the model provides the spatial distribution maps of instantaneous and yearly average PM10 over the PRD. It is proved that observed PM10 is more relevant to yearly mean AOT than instantaneous values.

  6. Organic richness, kerogen types and maturity in the shales of the Dakhla and Duwi formations in Abu Tartur area, Western Desert, Egypt: Implication of Rock–Eval pyrolysis

    Directory of Open Access Journals (Sweden)

    Mohamed M. El Nady

    2015-12-01

    Full Text Available The objective of this study is to assess the organic material for petroleum potential and characterize the relationships between organic material, thermal maturity, and the depositional environments. This is done using “14” samples from the shales of the Dakhla and Duwi formations in Abu Tartur area. The samples have been analyzed using the geochemical method of Rock–Eval pyrolysis. The analysis shows that the total organic carbon content lies between 0.56 and 1.96 wt%. It also shows that kerogen is a mixture of type II and III that is dominant, and is deposited in the shallow and restricted marine environment under prevailing reducing conditions. This type of kerogen is prone to oil and oil/gas production. The geochemical diagrams show that all the studied samples have good thermal maturation. The Dakhla and Duwi formations which have been divided into all zones are mature (have Tmax over 435 °C, and have organic carbon content located at the oil window (Tmax between 435 and 443 °C.

  7. Characterization of insoluble organic matter of the Lokpanta oil ...

    African Journals Online (AJOL)

    Conventional infrared (IR) spectroscopy was used to get quantitative information on the structure of the isolated kerogen of the Lokpanta oil shales in the Anambra basin. The kerogen was extracted from six shale samples collected from different geographical locations in the basin. Only about 1 to 14% of the kerogen ...

  8. Removal of High -Concentration and Refractory Organic Matter from Diosgenin Manufacture Wastewater : a case study of a demonstration project in Hubei Province, P R China

    Science.gov (United States)

    Bao, J.; Wang, L.

    2009-12-01

    Wastewater from diosgenin manufacture is dark brown (3,500 ~4,000 times of the chroma) and acidic(pH=0.8~1.5)with high concentration of organic matter(COD=25,000~38,000 mg/L)and poor biodegradability(BOD5/COD= 0.25~0.30). It is highly toxic to biota due to the water-soluble saponin, tannins and pectin. Therefore removal of the organic matter is of great importance before the discharge of the wastewater into the environment. Here we presented a set of data from a demonstration project in Hubei province, P R China with an improved technics. This technics, focusing on the treatment of diosgenin wastewater, included hydrolytic acidification, internal electrolysis, neutralization, aerating-improved Up-flow Anaerobic Sludge Bed (UASB) and bio-contact oxidation treatment in sequence to remove the organic matter. After 60 days of starting-up, the water quality from hydrolytic acidification reactor was greatly improved. The effluent became clear, indicating the obvious removal of suspended solids in the water; the ratio of BOD/COD increased to 0.44, suggesting an significant increase of biodegradability; the content of volatile fatty acid (VFA) increased from 22.6 mmol/L to 86.8 mmol/L and the volume loading of COD reached 9.48 kg COD/(m3d). Basically at this stage the removal efficiency of COD was stabilized at 25%. Further treatment was conducted on the effluent from hydrolytic acidification reactor through the Improved UASB Reactor after the internal electrolysis and neutralization. The Improved UASB Reactor can start up at room temperature with an influent of 1,500 mg/L COD and inflow rate of 50(m3/d). Then, temperature was increased gradually to 38 oC (± 2 oC) to optimize the growth of the mesophilic anaerobes in the reactor. The content of VFA of the effluent was controlled below 8 mmol/L to guarantee the pH in the range of 6.8~7.2. After 150 days of debugging, the COD of the influent to UASB increased to 9,600 mg/L, hydraulic retaining time (HRT) was around 70 hrs

  9. H-1 MR spectroscopy of the brain in multiple sclerosis subtypes with analysis of the metabolite concentrations in gray and white matter : initial findings

    NARCIS (Netherlands)

    Sijens, PE; Mostert, JP; Oudkerk, M; De Keyser, J

    Many MR spectroscopy (MRS) studies of multiple sclerosis (MS) have focussed on metabolism in normal-appearing white matter (NAWM) and in white matter lesions (WML). In this study, eight patients suffering from primary or secondary progressive MS (PPMS/SPMS) and seven patients with

  10. On the origin and variability of suspended particulate matter (PM1, PM2.5 and PM10) concentrations in Cyprus.

    Science.gov (United States)

    Pikridas, Michael; Vrekoussis, Mihalis; Mihalopoulos, Nikolaos; Kizas, Christos; Savvides, Chrysanthos; Sciare, Jean

    2017-04-01

    The Eastern Mediterranean (EM) lies at the crossroad of three different continents (Europe, Asia, and Africa). EM is a densely populated region including several cities with 3M inhabitants or more (e.g. Athens, Istanbul, Izmir, and Cairo). It has been identified as the most polluted area in Europe with respect to particulate matter (PM) mainly due to the combination of high photochemical activity, which causes pollutants to oxidize and partitioning in the particle phase, with the elevated pollutants emissions from neighboring regions. In addition, the proximity to Africa and the Middle East allows frequent transport of dust particles. At the center of the Eastern Mediterranean lies the island of Cyprus, which has received very little attention regarding its PM levels despite being the location in Europe most frequently impacted by air masses from the Middle East. Herewith, we present a historical PM archive that spans 2 decades. It involves ongoing monitoring on a daily basis of particulate matter with diameters smaller than 10 μm (PM10), 2.5 μm (PM2.5), and 1 μm (PM1) conducted in at least one, of the 12 currently existing air quality stations in Cyprus since 1997, 2005, and 2009, respectively. The most extended PM datasets correspond a) to the Agia Marina Xyliatou (AMX) monitoring station established at a remote area at the foothills of mount Troodos and b) that of the inland capital, Nicosia. Based on this long-term dataset, the diurnal, temporal and annual variability is assessed. Prior to 2010, PM10 concentration at all sites remained relatively constant, but at different levels, violating the annual EU legislated PM10 limit of 40 μg m-3. Since 2010, coarse mode levels have decreased at all sites. The reported decrease was equal to 30% at AMX. As a result, since 2010 the observed levels comply with the EU legislation threshold. Satellite observations of Aerosol Optical Thickness (AOT) Moderate Resolution Imaging Spectroradiometer (MODIS) onboard NASA

  11. Study of new germanium bolometers with interleaved concentric electrodes for non-baryonic cold dark matter direct detection in the Edelweiss-II experiment

    International Nuclear Information System (INIS)

    Domange, J.

    2011-09-01

    EDELWEISS is a direct non-baryonic cold dark matter detection experiment in the form of weakly interacting massive particles (also known as WIMPs), which currently constitute the most popular candidates to account for the missing mass in the Universe. To this purpose, EDELWEISS uses germanium bolometers at cryogenic temperature (20 mK approximately) in the Underground Laboratory of Modane (LSM) at the French-Italian border. Since 2008, a new type of detector is operated, equipped with concentric electrodes to optimize the rejection of surface events (coplanar-grid detectors). This thesis work is divided into several research orientations. First, we carried out measurements concerning charge collection in the crystals. The velocity laws of the carriers (electrons and holes) have been determined in germanium at 20 mK in the orientation, and a complete study of charge sharing has been done, including an evaluation of the transport anisotropy and of the straggling of the carriers. These results lead to a better understanding of the inner properties of the EDELWEISS detectors. Then, studies relating to the improvement of the performances were carried out. In particular, we have optimized the space-charge cancellation procedure in the crystals and improved the passive rejection of surface events (β). The fiducial volume of the detectors has been evaluated using two X-ray lines from cosmically activated radionuclides: 68 Ge and 65 Zn. Finally, an exhaustive study of the low energy spectra has been carried out, which makes it possible to develop a systematic analysis method for the search of low-mass WIMPs in EDELWEISS. (author)

  12. Characterization of size, number, concentration and morphology of particulate matter emitted from a high performance diesel combustion system using biomass derived fuels

    Energy Technology Data Exchange (ETDEWEB)

    Bhardwaj, Om Parkash; Krishnamurthy, Ketan; Kremer, Florian; Pischinger, Stefan [RWTH Aachen Univ. (Germany). Inst. for Combustion Engines; Berg, Angelika von; Roth, Georg [RWTH Aachen Univ. (Germany). Inst. of Crystallography; Lueers, Bernhard; Kolbeck, Andreas; Koerfer, Thomas [FEV GmbH, Aachen (Germany)

    2013-06-01

    Motor vehicle emissions have been identified as a major source of particulates. Although the low limits of particulate matter cause a need for a particulate trap in most of the present day diesel engines, the physical and chemical characterization of particles with the measures of size, number, volatility and reactivity etc. is of increasing interest with respect to the regeneration frequency and regeneration efficiency of a particulate trap. Within the Cluster of Excellence ''Tailor-Made Fuels from Biomass (TMFB)'' at RWTH Aachen University, the Institute for Combustion Engines carried out a detailed investigation program to explore the potential of future biofuel candidates for future combustion systems. The experiments for particulate measurements and analysis were conducted on a EURO 6 compliant High Efficiency Diesel Combustion System (HECS) with petroleum based diesel fuel as reference and today's biofuel (i.e. FAME) as well as a potential future biomass derived fuel candidate (i.e. 2-MTHF I DBE), being developed under TMFB approach. Soot samples collected on polycarbonate filters were analyzed using SEM; revealing vital informations regarding particle size distribution. Furthermore, thermophoretic sampling was also performed on copper grids and samples were analyzed using TEM to determine its graphitic micro-structure. In addition, X-Ray diffraction (XRD) measurements were also performed to get further quantitative information regarding crystal lattice parameters and structure of investigated soot. The results indicate more than 90% reduction in the mass and number concentrations of engine out particle emissions using future biomass derived fuel candidate. A good co-relation was observed between TEM micro-structure results and quantitative crystal lattice and structure information obtained from XRD studies, indicating higher reactivity for soot emitted from 2-MTHF/DBE. (orig.)

  13. Molecular environment of stable iodine and radioiodine (129I) in natural organic matter: Evidence inferred from NMR and binding experiments at environmentally relevant concentrations

    Science.gov (United States)

    Xu, Chen; Zhong, Junyan; Hatcher, Patrick G.; Zhang, Saijin; Li, Hsiu-Ping; Ho, Yi-Fang; Schwehr, Kathleen A.; Kaplan, Daniel I.; Roberts, Kimberly A.; Brinkmeyer, Robin; Yeager, Chris M.; Santschi, Peter H.

    2012-11-01

    129I is a major by-product of nuclear fission and had become one of the major radiation risk drivers at Department of Energy (DOE) sites. 129I is present at elevated levels in the surface soils of the Savannah River Site (SRS) F-Area and was found to be bound predominantly to soil organic matter (SOM). Naturally bound 127I and 129I to sequentially extracted humic acids (HAs), fulvic acids (FAs) and a water extractable colloid (WEC) were measured in a 129I-contaminated wetland surface soil located on the SRS. WEC is a predominantly colloidal organic fraction obtained from soil re-suspension experiments to mimic the fraction that may be released during groundwater exfiltration, storm water or surface runoff events. For the first time, NMR techniques were applied to infer the molecular environment of naturally occurring stable iodine and radioiodine binding to SOM. Iodine uptake partitioning coefficients (Kd) by these SOM samples at ambient iodine concentrations were also measured and related to quantitative structural analyses by 13C DPMAS NMR and solution state 1H NMR on the eight humic acid fractions. By assessing the molecular environment of iodine, it was found that it was closely associated with the aromatic regions containing esterified products of phenolic and formic acids or other aliphatic carboxylic acids, amide functionalities, quinone-like structures activated by electron-donating groups (e.g., NH2), or a hemicellulose-lignin-like complex with phenyl-glycosidic linkages. However, FAs and WEC contained much greater concentrations of 127I or 129I than HAs. The contrasting radioiodine contents among the three different types of SOM (HAs, FAs and WEC) suggest that the iodine binding environment cannot be explained solely by the difference in the amount of their reactive binding sites. Instead, indirect evidence indicates that the macro-molecular conformation, such as the hydrophobic aliphatic periphery hindering the active aromatic cores and the hydrophilic

  14. Molecular indicators for palaeoenvironmental change in a Messinian evaporitic sequence Vena del Gesso, Italy III. Stratigraphic changes in the molecular structure of kerogen in a single marl bed as revealed by flash pyrolysis

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Gelin, F.; Harrison, W.N.; Maxwell, J.R.

    1995-01-01

    Kerogens of nine samples from a single marl bed of the Gessoso-solfifera Formation in the Vena del Gesso basin (Messinian, Italy) were qualitatively and quantitatively studied by analytical pyrolysis. Relationships between the nature of the pyrolysis products and the source organisms were

  15. Omega-3 Fatty Acid Attenuates Cardiovascular Effects in Healthy Older Volunteers Exposed to Concentrated Ambient Fine and UltrafineParticulate Matter

    Science.gov (United States)

    Rationale: Ambient particulate matter (PM) exposure has been associated with adverse cardiovascular effects. A recent epidemiology study reported that omega-3 polyunsaturated fatty acid (fish oil) supplementation blunted the response of study participants to PM. Our study was des...

  16. Impacts of future climate change and effects of biogenic emissions on surface ozone and particulate matter concentrations in the United States

    Directory of Open Access Journals (Sweden)

    Y. F. Lam

    2011-05-01

    Full Text Available Simulations of present and future average regional ozone and PM2.5 concentrations over the United States were performed to investigate the potential impacts of global climate change and emissions on regional air quality using CMAQ. Various emissions and climate conditions with different biogenic emissions and domain resolutions were implemented to study the sensitivity of future air quality trends from the impacts of changing biogenic emissions. A comparison of GEOS-Chem and CMAQ was performed to investigate the effect of downscaling on the prediction of future air quality trends. For ozone, the impacts of global climate change are relatively smaller when compared to the impacts of anticipated future emissions reduction, except for the Northeast area, where increasing biogenic emissions due to climate change have stronger positive effects (increases to the regional ozone air quality. The combination effect from both climate change and emission reductions leads to approximately a 10 % or 5 ppbv decrease of the maximum daily average eight-hour ozone (MDA8 over the Eastern United States. For PM2.5, the impacts of global climate change have shown insignificant effect, where as the impacts of anticipated future emissions reduction account for the majority of overall PM2.5 reductions. The annual average 24-h PM2.5 of the future-year condition was found to be about 40 % lower than the one from the present-year condition, of which 60 % of its overall reductions are contributed to by the decrease of SO4 and NO3 particulate matters. Changing the biogenic emissions model increases the MDA8 ozone by about 5–10 % or 3–5 ppbv in the Northeast area. Conversely, it reduces the annual average PM2.5 by 5 % or 1.0 μg m−3 in the Southeast region.

  17. Concentrations of Platinum Group Elements (Pt, Pd, Rh) in Airborne Particulate Matter (PM2.5 and PM10-2.5) Collected at Selected Canadian Urban Sites: a Case Study

    OpenAIRE

    Celo V.; Zhao J. J.; Dabek-Zlotorzynska E.

    2013-01-01

    Increasing environmental concentrations of platinum group elements (PGEs), in particular platinum (Pt), palladium (Pd) and rhodium (Rh), from catalytic converters has been reported worldwide. Initially it was believed that the emitted PGEs remain in the roadside environment, but recent studies have shown that fine PGE-containing particles can be transported and distributed at regional and long-range levels. Therefore, the monitoring of PGEs in airborne particulate matter (PM) is important for...

  18. Influence of sulfate reduction on the organic matter of Wealden sediments of the Lower Saxony Basin (Germany)

    Energy Technology Data Exchange (ETDEWEB)

    Berner, U. [Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR), Hannover (Germany)

    2013-08-01

    Sediments of the Wealden (Lower Saxony Basin, Germany) as obtained from the well Isterberg 1001 consist of clay stones, marls and few massive carbonate horizons. Although, the basin is predominantly characterized as lacustrine geochemical data indicate significant influences of marine ingression which have introduced sulfur into the depositional system. Consequently the organic matter of the sediments has been substantially affected by bacterial sulfate reduction, which has led to losses of the initial organic carbon of 5 to 80 wt.- percent, which is a minimum estimate as losses of H{sub 2}S form the sediments were not taken into account for the mass balance consideration. Complete uptake of reactive iron into sulfides has led in a significant number of samples to the presence of excess sulfur not contained in sulfides. In our argumentation we assume that excess sulfur is at least partly incorporated into the organic matter. Pyrolysis investigations show that organic matter in samples containing higher amounts of excess sulfur generates hydrocarbons at lower temperatures than samples with low concentrations of excess sulfur. These observations are compatible with findings usually reported for Type S-II kerogens. The likely organically bound excess sulfur introduces a bias with thermal maturities from RockEval pyrolysis, which implies that T{sub max} data rather reflect quality changes of the organic matter than thermal maturity in the investigated Wealden sediments. The hydrocarbon potential has been reduced significantly in samples which have been affected strongly by the microbial process as indicated by hydrogen indices of the sediments. The observations of variable degrees of sulfate reduction indicate also a variation of organic matter fluxes to the sediment surface of the palaeo-lake likely resulting from changes in biological surface productivity. Low carbon fluxes likely coincide with extensive use of organic substrate by sulfate reducers whereas high

  19. Effects on nano zero-valent iron reactivity of interactions between hardness, alkalinity, and natural organic matter in reverse osmosis concentrate

    DEFF Research Database (Denmark)

    Hwang, Yuhoon; Shin, Hang-Sik

    2013-01-01

    , the influence of hardness, alkalinity, and organic matter on NZVI reactivity was evaluated by the response surface method (RSM). Hardness (Ca2 ) had a positive effect on NZVI reactivity by accelerating iron corrosion. In contrast, alkalinity (bicarbonate; HCO3-) and organic matter (humic acid; HA) had negative...... effects on NZVI reactivity due to morphological change to carbonate green rust, and to competitive adsorption of HA, respectively. The validity of the statistical prediction model derived from RSM was confirmed by an additional confirmation experiment, and the experimental result was within the 95......% confidential interval. Therefore, it can be said that the RSM model produced results that were statistically significant....

  20. Study on Concentration of Particulate Matter with Diameter Less than 10 Microns, Heavy Metals and Polycyclic Aromatic Hydrocarbons Related to PM2.5 in the Ambient Air of Sina Hospital District

    Directory of Open Access Journals (Sweden)

    Majid Kermani

    2014-03-01

    Full Text Available Background:In recent decades, extensive studies have shown a number of short and long-term health effects of particle matters. In addition to particle matters, polycyclic aromatic hydrocarbons (PAHs and heavy metals in airborne particles due to their mutagenic and carcinogenic properties are considered major air pollutants. So, the aim of this study was to evaluate the concentration of PM2.5particulate, 7heavy metal concentrations and 13 PAHs compound associated with fine particles (PM2.5-boud PAHs in the district of Sina hospital, Tehran. Methods: This cross-sectional study was carried out in air of Sina Hospital district in Tehran. Concentrations of fine particulate matter (PM2.5 were determined by gravimetric. Also heavy metal concentrations in samples after digestion were determined with ICP-AES instrument through injection. Then the PAHs compounds from each sample were extracted by ultrasonic method. After this step, extracted sample was injected for analysis by GC-MS and concentration of each compound was read. Results: The daily average concentration of PM2.5 during the study was 41.19 µg/m3.Concentration values for zinc, lead, cadmium, chromium, nickel and arsenic, were 92/69, 05/38, 2/18, 24/4, 19/4 and 34/1 ng/m3 respectively but mercury not found in this study. Average concentrations of PAHs compounds have been variable from0.07 ng/m3 for Chrysene to 1.21ng/m3 for Dibenzo(ahanthracene. Conclusion: In this study, the daily average of PM2.5 concentrations was above the Iranian National PM, WHO (25 µg/m3 and EPA (35 µg/m3 standards established for PM2.5 particles. Heavy metal concentrations in this study were lower than values reported in previous studies in Tehran. The highest concentrations among PAHs compounds belonging toIndeo(cd 1,2,3pyren, Dibenzo(ah anthracene, Benzo (B flouranthin and Benzo (Kflouranthin that all of these compounds are related to vehicle emissions.

  1. THE INFLUENCE OF PARTICULATE MATTER OF AMBIENT ORIGIN UPON INDOOR RESIDENTIAL MASS CONCENTRATIONS INVOLVING SENSITIVE SUBPOPULATIONS-RESULTS FROM LONGITUDINAL PANEL STUDIES

    Science.gov (United States)

    The US EPA has completed field data collections from a series of longitudinal particulate matter (PM) exposure panel field studies. These studies were conducted in Baltimore, Maryland (1998), Fresno, California (1999), and Research Triangle Park (RTP), North Carolina (2000-2001) ...

  2. Effect of granular activated carbon concentration on the content of organic matter and salt, influencing E. coli activity and survival in fluidized bed disinfection reactor

    NARCIS (Netherlands)

    Racyte, J.; Langenhoff, A.A.M.; Ribeiro, A.F.M.M.R.; Paulitsch-Fuchs, A.H.; Bruning, H.; Rijnaarts, H.

    2014-01-01

    Granular activated carbon (GAC) is used in water treatment systems, typically to remove pollutants such as natural organic matter, volatile organic compounds, chlorine, taste, and odor. GAC is also used as a key component of a new technology that combines a fluidized bed reactor with radio frequency

  3. Definition of new trace-metal proxies for the controls on organic matter enrichment in marine sediments based on Mn, Co, Mo and Cd concentrations

    NARCIS (Netherlands)

    Sweere, T.; Van den Boorn, S.; Dickson, A.J.; Reichart, G.-J.

    2016-01-01

    Trace metal enrichments in sedimentary deposits are of prime interest because they are governed by processes that also control the production and preservation of organic matter. Consequently, trace metals have been used in reconstructions of the (palaeo)depositional environment of organic-rich

  4. Estimating absorption coefficients of colored dissolved organic matter (CDOM) using a semi-analytical algorithm for Southern Beaufort Sea (Canadian Arctic) waters: application to deriving concentrations of dissolved organic carbon from space

    Science.gov (United States)

    Matsuoka, A.; Hooker, S. B.; Bricaud, A.; Gentili, B.; Babin, M.

    2012-10-01

    A series of papers have suggested that freshwater discharge, including a large amount of dissolved organic matter (DOM), has increased since the middle of the 20th century. In this study, a semi-analytical algorithm for estimating light absorption coefficients of the colored fraction of DOM (CDOM) was developed for Southern Beaufort Sea waters using remote sensing reflectance at six wavelengths in the visible spectral domain corresponding to MODIS ocean color sensor. This algorithm allows to separate colored detrital matter (CDM) into CDOM and non-algal particles (NAP) by determining NAP absorption using an empirical relationship between NAP absorption and particle backscattering coefficients. Evaluation using independent datasets, that were not used for developing the algorithm, showed that CDOM absorption can be estimated accurately to within an uncertainty of 35% and 50% for oceanic and turbid waters, respectively. In situ measurements showed that dissolved organic carbon (DOC) concentrations were tightly correlated with CDOM absorption (r2 = 0.97). By combining the CDOM absorption algorithm together with the DOC versus CDOM relationship, it is now possible to estimate DOC concentrations in the near-surface layer of the Southern Beaufort Sea using satellite ocean color data. DOC concentrations in the surface waters were estimated using MODIS ocean color data, and the estimates showed reasonable values compared to in situ measurements. We propose a routine and near real-time method for deriving DOC concentrations from space, which may open the way to an estimate of DOC budgets for Arctic coastal waters.

  5. Quantifying Matter

    CERN Document Server

    Angelo, Joseph A

    2011-01-01

    Quantifying Matter explains how scientists learned to measure matter and quantify some of its most fascinating and useful properties. It presents many of the most important intellectual achievements and technical developments that led to the scientific interpretation of substance. Complete with full-color photographs, this exciting new volume describes the basic characteristics and properties of matter. Chapters include:. -Exploring the Nature of Matter. -The Origin of Matter. -The Search for Substance. -Quantifying Matter During the Scientific Revolution. -Understanding Matter's Electromagnet

  6. Increased cortical and deep grey matter sodium concentration is associated with physical and cognitive disability in relapse-onset multiple sclerosis

    DEFF Research Database (Denmark)

    Brownlee, WJ; Alves Da Mota, Patricia; Prados, Ferran

    digit modalities test (SDMT) and tests of verbal and visual memory. Linear regression was used to compare differences in tissue TSC between groups. Multivariable linear regression was used to identify independent associations between TSC and disability with adjustment for age, sex, disease duration......=0.40) and visual memory (β=-0.06, 95%CI -0.11, -.0.02, R2=0.19). Conclusion: Sodium accumulation in cortical and deep grey matter may reflect underlying neurodegeneration that is relevant to the development of long-term disability and cognitive impairment in relapse-onset MS. 23Na-MRI may become a secondary......-appearing white matter (NAWM), T1-isointense and T1-hypointense lesions was calculated. Physical disability was assessed using the Expanded Disability Status Scale (EDSS), timed 25-foot walk test (TWT) and 9-hole peg test (9HPT). Cognition was assessed using the paced auditory serial addition test (PASAT), symbol...

  7. Response of saprotrophic microfungi degrading the fulvic fraction of soil organic matter to different n fertilization intensities, different plant species cover and elevated atmospheric CO2 concentration

    Czech Academy of Sciences Publication Activity Database

    Strnadová, Veronika; Hršelová, Hana; Kolařík, Miroslav; Gryndler, Milan

    2004-01-01

    Roč. 49, č. 5 (2004), s. 563-568 ISSN 0015-5632 R&D Projects: GA ČR GA526/03/0188; GA ČR GD206/03/H137 Institutional research plan: CEZ:AV0Z5020903 Keywords : saprotrophic microfungi * soil organic matter Subject RIV: EE - Microbiology, Virology Impact factor: 1.034, year: 2004

  8. Laboratory simulated hydrothermal alteration of sedimentary organic matter from Guaymas Basin, Gulf of California. Ph.D. Thesis

    Science.gov (United States)

    Leif, Roald N.

    1993-01-01

    High temperature alteration of sedimentary organic matter associated with marine hydrothermal systems involves complex physical and chemical processes that are not easily measured in most natural systems. Many of these processes can be evaluated indirectly by examining the geochemistry of the hydrothermal system in the laboratory. In this investigation, an experimental organic geochemical approach to studying pyrolysis of sedimentary organic matter is applied to the hydrothermal system in the Guaymas Basin, Gulf of California. A general survey of hydrothermal oils and extractable organic matter (bitumen) in hydrothermally altered sediments identified several homologous series of alkanones associated with a high temperature hydrothermal origin. The alkanones range in carbon number from C11 to C30 with no carbon number preference. Alkan-2-ones are in highest concentrations, with lower amounts of 3-, 4-, 5- (and higher) homologs. The alkanones appear to be pyrolysis products synthesized under extreme hydrothermal conditions. Hydrous pyrolysis and confinement pyrolysis experiments were performed to simulate thermally enhanced diagenetic and catagenetic changes in the immature sedimentary organic matter. The extent of alteration was measured by monitoring the n-alkanes, acyclic isoprenoids, steroid and triterpenoid biomarkers, polycyclic aromatic hydrocarbons and alkanones. The results were compared to bitumen extracts from sediments which have been naturally altered by a sill intrusion and accompanied hydrothermal fluid flow. These pyrolysis experiments duplicated many of the organic matter transformations observed in the natural system. Full hopane and sterane maturation occurred after 48 hr in experiments at 330 deg C with low water/rock mass ratios (0.29). A variety of radical and ionic reactions are responsible for the organic compound conversions which occur under extreme hydrothermal conditions. Short duration pyrolysis experiments revealed that a portion of the

  9. Characterization and quantification by mass spectrometry of mobile organic matter from clay rock: influence of the origin and of the sampling

    International Nuclear Information System (INIS)

    Huclier-Markai, S.; Landesman, C.; Montavon, G.; Grambow, B.; Monteau, F.; Fernandez, A.M.; Vinsot, A.

    2012-01-01

    probable low velocity, that the inventory was focused on the small organic molecules. The influence of the sampling was studied, notably by performing an experiment in which the argillite core sample was squeezed for 28 days at 175 MPa. The initial water content of the sample was 5.3% and the concentration of organic matter XX mol C/L. The structural features observed for the DOM were different from the percolated water samples either obtained in situ from the POX 1601 borehole or in lab from EST 34399 cores than for the squeezed water sample. The influence of the water collection will be discussed. Additionally, a part of organic matter can be extracted and isolated by HCl/HF treatment. This corresponds to the kerogen fraction which is insoluble in the pore water. 150 Myears solid-bound organic matter of the COx has been already investigated in several studies and originates from a mixture of marine and terrestrial sources. In addition to this, the CCl4 soluble organic fraction (bitumen) has been already characterized by liquid and gas chromatography coupled to mass spectrometry. And finally, a small fraction of the kerogen can be mobilized under alkaline conditions from the COx, a scenario which could happen at the COx/cement interface. This fraction (approx. 0,002 mol C/L) could be transported in the pore water and has been characterized to contain small molecules with carboxylic and phenolic groups. Nonetheless, in order to predict the speciation of metals and radionuclides for a given scenario, Dissolved Organic Matter (DOM) either in the pore water or that could be mobilized from the kerogen fraction must be supported by quantitative data. Thus, the present study is focused the quantification of these low molecular weight compounds using mass spectrometry. Several simple, sensitive, and reproducible methods of quantification, such as internal calibration, calibrated addition of external standard or sequential tandem mass spectrometry, have been developed and are

  10. Increased cortical and deep grey matter sodium concentration is associated with physical and cognitive disability in relapse-onset multiple sclerosis

    DEFF Research Database (Denmark)

    Brownlee, WJ; Alves Da Mota, Patricia; Prados, Ferran

    digit modalities test (SDMT) and tests of verbal and visual memory. Linear regression was used to compare differences in tissue TSC between groups. Multivariable linear regression was used to identify independent associations between TSC and disability with adjustment for age, sex, disease duration......=0.40) and visual memory (β=-0.06, 95%CI -0.11, -.0.02, R2=0.19). Conclusion: Sodium accumulation in cortical and deep grey matter may reflect underlying neurodegeneration that is relevant to the development of long-term disability and cognitive impairment in relapse-onset MS. 23Na-MRI may become a secondary...

  11. Composition and concentration of soluble and particulate matter in the coolant of the reactor primary cooling system of the Embalse nuclear power plant

    International Nuclear Information System (INIS)

    Chocron, Mauricio; Garcia Rodenas, Luis; La Gamma, Ana M.; Villegas, Marina; Fernandez, Alberto N.; Allemandi, Walter; Manera, Raul; Rosales, Hugo

    2000-01-01

    Nuclear power plants type PWR and PHWR (pressurized water reactor and pressurized heavy water reactor) have three coolant circuits which only exchange energy among them. The primary circuit, whose coolant extracts the reactor energy, the secondary circuit or water-steam cycle and the tertiary circuit which could be lake, river or sea water. The chemistry of the primary and secondary coolants is carefully controlled with the aim of minimizing the corrosion of structural materials. However, very low rates of corrosion are inevitable and one of the consequences of the corrosion processes is the presence of soluble and particulate matter in the coolant from where several problems associated with mass transfer arisen. In this way radioactive nuclides are transported out of the core to the steam generators, hydraulic resistance increases and heat transfer capability degrades. In the present paper some alternative techniques are proposed for the quantification of both, the particulate and soluble matter present in the coolant and their correspondent composition. Some results are also included and discussed. (author)

  12. Direct sampling of sub-µm atmospheric particulate organic matter in sub-ng m-3 mass concentrations by proton-transfer-reaction mass spectrometry

    Science.gov (United States)

    Armin, W.; Mueller, M.; Klinger, A.; Striednig, M.

    2017-12-01

    A quantitative characterization of the organic fraction of atmospheric particulate matter is still challenging. Herein we present the novel modular "Chemical Analysis of Aerosol Online" (CHARON) particle inlet system coupled to a new-generation proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF 6000 X2, Ionicon Analytik, Austria) that quantitatively detects organic analytes in real-time and sub-pptV levels by chemical ionization with hydronium reagent ions. CHARON consists of a gas-phase denuder for stripping off gas-phase analytes (efficiency > 99.999%), an aerodynamic lens for particle collimation combined with an inertial sampler for the particle-enriched flow and a thermodesorption unit for particle volatilization prior to chemical analysis. With typical particle enrichment factors of around 30 for particle diameters (DP) between 120 nm and 1000 nm (somewhat reduced enrichment for 60 nm 6000) and excellent mass accuracies (< 10 ppm) chemical compositions can be assigned and included in further analyses. In addition to a detailed characterization of the CHARON PTR-TOF 6000 X2 we will present first results on the chemical composition of sub-µm particulate organic matter in the urban atmosphere in Innsbruck (Austria).

  13. Air oxidation and biodegradation of the organic matter from the Boom Claycomparison between artificial and natural altered series

    International Nuclear Information System (INIS)

    Blanchart, Pascale; Faure, Pierre; Michels, Raymond; Bruggeman, Christophe; De Craen, Mieke

    2010-01-01

    Document available in extended abstract form only. The Boom Clay formation (Belgium) is studied as the reference host rock for methodological studies on the geological disposal of high-level and long-lived radioactive waste. The drilling of galleries in the Boom Clay at Mol lead to the perturbation of the initial physical and chemical conditions. Since organic matter is present in this argillaceous formation, it is important to know its response to these new conditions. The Boom Clay is of Tertiary age (Rupelian) and has a TOC content up to 5%. Its pore water (20% in mass of rock) contains significant quantities of Dissolved Organic Carbon (DOC) with a mean concentration of 115+/-15 mg/L, determined on the basis of piezometer water as well as squeezing and leaching experiments. Yet, in piezometers, the DOC may show considerable and irregular variations through time, with values ranging between 80 and 425 mg/L. The origin and bio-physico-chemical controls of such variations are yet unknown. Perturbation of the in-situ conditions of the clay is a possible reason for such observation. More likely the introduction of air as well as micro-organisms may have an impact that needs to be estimated. Well-preserved, freshly-drilled Boom Clay samples, as well as samples of different degrees of alteration (air exposed clay from the older galleries) were collected with the aim of determining and quantifying different molecular markers representative for the alteration degree. Additionally, increasing artificial air oxidation experiments were carried out on fresh Praclay samples (sampled during the PRACLAY gallery excavation) in order to obtain an altered reference series. Moreover PRACLAY samples previously extracted with an organic solvent (dichloromethane) were also prepared in order to identify the influence of the kerogen during oxidation. In these experiments, powdered clay was heated at 80 deg. C under air flow during 1, 3, 6, 9, 12, 18 months. Organic matter composition

  14. A comparison of individual cow versus group concentrate allocation strategies on dry matter intake, milk production, tissue changes, and fertility of Holstein-Friesian cows offered a grass silage diet.

    Science.gov (United States)

    Little, M W; O'Connell, N E; Ferris, C P

    2016-06-01

    A diverse range of concentrate allocation strategies are adopted on dairy farms. The objectives of this study were to examine the effects on cow performance [dry matter (DM) intake (DMI), milk yield and composition, body tissue changes, and fertility] of adopting 2 contrasting concentrate allocation strategies over the first 140 d of lactation. Seventy-seven Holstein-Friesian dairy cows were allocated to 1 of 2 concentrate allocation strategies at calving, namely group or individual cow. Cows on the group strategy were offered a mixed ration comprising grass silage and concentrates in a 50:50 ratio on a DM basis. Cows on the individual cow strategy were offered a basal mixed ration comprising grass silage and concentrates (the latter included in the mix to achieve a mean intake of 6kg/cow per day), which was formulated to meet the cow's energy requirements for maintenance plus 24kg of milk/cow per day. Additional concentrates were offered via an out-of-parlor feeding system, with the amount offered adjusted weekly based on each individual cow's milk yield during the previous week. In addition, all cows received a small quantity of straw in the mixed ration part of the diet (approximately 0.3kg/cow per day), plus 0.5kg of concentrate twice daily in the milking parlor. Mean concentrate intakes over the study period were similar with each of the 2 allocation strategies (11.5 and 11.7kg of DM/cow per day for group and individual cow, respectively), although the pattern of intake with each treatment differed over time. Concentrate allocation strategy had no effect on either milk yield (39.3 and 38.0kg/d for group and individual cow, respectively), milk composition, or milk constituent yield. The milk yield response curves with each treatment were largely aligned with the concentrate DMI curves. Cows on the individual cow treatment had a greater range of concentrate DMI and milk yields than those on the group treatment. With the exception of a tendency for cows on the

  15. Plant induced changes in concentrations of caesium, strontium and uranium in soil solution with reference to major ions and dissolved organic matter

    International Nuclear Information System (INIS)

    Takeda, Akira; Tsukada, Hirofumi; Takaku, Yuichi; Akata, Naofumi; Hisamatsu, Shun'ichi

    2008-01-01

    For a better understanding of the soil-to-plant transfer of radionuclides, their behavior in the soil solution should be elucidated, especially at the interface between plant roots and soil particles, where conditions differ greatly from the bulk soil because of plant activity. This study determined the concentration of stable Cs and Sr, and U in the soil solution, under plant growing conditions. The leafy vegetable komatsuna (Brassica rapa L.) was cultivated for 26 days in pots, where the rhizosphere soil was separated from the non-rhizosphere soil by a nylon net screen. The concentrations of Cs and Sr in the rhizosphere soil solution decreased with time, and were controlled by K + NH 4 + and Ca, respectively. On the other hand, the concentration of U in the rhizosphere soil solution increased with time, and was related to the changes of DOC; however, this relationship was different between the rhizosphere and non-rhizosphere soil

  16. Plant induced changes in concentrations of caesium, strontium and uranium in soil solution with reference to major ions and dissolved organic matter.

    Science.gov (United States)

    Takeda, Akira; Tsukada, Hirofumi; Takaku, Yuichi; Akata, Naofumi; Hisamatsu, Shun'ichi

    2008-06-01

    For a better understanding of the soil-to-plant transfer of radionuclides, their behavior in the soil solution should be elucidated, especially at the interface between plant roots and soil particles, where conditions differ greatly from the bulk soil because of plant activity. This study determined the concentration of stable Cs and Sr, and U in the soil solution, under plant growing conditions. The leafy vegetable komatsuna (Brassica rapa L.) was cultivated for 26 days in pots, where the rhizosphere soil was separated from the non-rhizosphere soil by a nylon net screen. The concentrations of Cs and Sr in the rhizosphere soil solution decreased with time, and were controlled by K+NH(4)(+) and Ca, respectively. On the other hand, the concentration of U in the rhizosphere soil solution increased with time, and was related to the changes of DOC; however, this relationship was different between the rhizosphere and non-rhizosphere soil.

  17. Mass concentration, optical depth and carbon composition of particulate matter in the major southern West African cities of Cotonou (Benin) and Abidjan (Côte d'Ivoire)

    Science.gov (United States)

    Djossou, Julien; Léon, Jean-François; Barthélemy Akpo, Aristide; Liousse, Cathy; Yoboué, Véronique; Bedou, Mouhamadou; Bodjrenou, Marleine; Chiron, Christelle; Galy-Lacaux, Corinne; Gardrat, Eric; Abbey, Marcellin; Keita, Sékou; Bahino, Julien; Touré N'Datchoh, Evelyne; Ossohou, Money; Awanou, Cossi Norbert

    2018-05-01

    Air quality degradation is a major issue in the large conurbations on the shore of the Gulf of Guinea. We present for the first time PM2.5 time series collected in Cotonou, Benin, and Abidjan, Côte d'Ivoire, from February 2015 to March 2017. Measurements were performed in the vicinity of major combustion aerosol sources: Cotonou/traffic (CT), Abidjan/traffic (AT), Abidjan/landfill (AL) and Abidjan/domestic fires (ADF). We report the weekly PM2.5 mass and carbonaceous content as elemental (EC) and organic (OC) carbon concentrations. We also measure the aerosol optical depth (AOD) and the Ångström exponent in both cities. The average PM2.5 mass concentrations were 32 ± 32, 32 ± 24 and 28 ± 19 µg m-3 at traffic sites CT and AT and landfill site AL, respectively. The domestic fire site shows a concentration of 145 ± 69 µg m-3 due to the contribution of smoking and roasting activities. The highest OC and EC concentrations were also measured at ADF at 71 ± 29 and 15 ± 9 µg m-3, respectively, while the other sites present OC concentration between 8 and 12 µg m-3 and EC concentrations between 2 and 7 µg m-3. The OC / EC ratio is 4.3 at CT and 2.0 at AT. This difference highlights the influence of two-wheel vehicles using gasoline in Cotonou compared to that of four-wheel vehicles using diesel fuel in Abidjan. AOD was rather similar in both cities, with a mean value of 0.58 in Cotonou and of 0.68 in Abidjan. The seasonal cycle is dominated by the large increase in surface mass concentration and AOD during the long dry season (December-February) as expected due to mineral dust advection and biomass burning activities. The lowest concentrations are observed during the short dry season (August-September) due to an increase in surface wind speed leading to a better ventilation. On the other hand, the high PM2.5 / AOD ratio in the short wet season (October-November) indicates the stagnation of local pollution.

  18. Mass concentration, optical depth and carbon composition of particulate matter in the major southern West African cities of Cotonou (Benin and Abidjan (Côte d'Ivoire

    Directory of Open Access Journals (Sweden)

    J. Djossou

    2018-05-01

    Full Text Available Air quality degradation is a major issue in the large conurbations on the shore of the Gulf of Guinea. We present for the first time PM2.5 time series collected in Cotonou, Benin, and Abidjan, Côte d'Ivoire, from February 2015 to March 2017. Measurements were performed in the vicinity of major combustion aerosol sources: Cotonou/traffic (CT, Abidjan/traffic (AT, Abidjan/landfill (AL and Abidjan/domestic fires (ADF. We report the weekly PM2.5 mass and carbonaceous content as elemental (EC and organic (OC carbon concentrations. We also measure the aerosol optical depth (AOD and the Ångström exponent in both cities. The average PM2.5 mass concentrations were 32 ± 32, 32 ± 24 and 28 ± 19 µg m−3 at traffic sites CT and AT and landfill site AL, respectively. The domestic fire site shows a concentration of 145 ± 69 µg m−3 due to the contribution of smoking and roasting activities. The highest OC and EC concentrations were also measured at ADF at 71 ± 29 and 15 ± 9 µg m−3, respectively, while the other sites present OC concentration between 8 and 12 µg m−3 and EC concentrations between 2 and 7 µg m−3. The OC ∕ EC ratio is 4.3 at CT and 2.0 at AT. This difference highlights the influence of two-wheel vehicles using gasoline in Cotonou compared to that of four-wheel vehicles using diesel fuel in Abidjan. AOD was rather similar in both cities, with a mean value of 0.58 in Cotonou and of 0.68 in Abidjan. The seasonal cycle is dominated by the large increase in surface mass concentration and AOD during the long dry season (December–February as expected due to mineral dust advection and biomass burning activities. The lowest concentrations are observed during the short dry season (August–September due to an increase in surface wind speed leading to a better ventilation. On the other hand, the high PM2.5 ∕ AOD ratio in the short wet season (October–November indicates the

  19. Estimating absorption coefficients of colored dissolved organic matter (CDOM) using a semi-analytical algorithm for southern Beaufort Sea waters: application to deriving concentrations of dissolved organic carbon from space

    Science.gov (United States)

    Matsuoka, A.; Hooker, S. B.; Bricaud, A.; Gentili, B.; Babin, M.

    2013-02-01

    A series of papers have suggested that freshwater discharge, including a large amount of dissolved organic matter (DOM), has increased since the middle of the 20th century. In this study, a semi-analytical algorithm for estimating light absorption coefficients of the colored fraction of DOM (CDOM) was developed for southern Beaufort Sea waters using remote sensing reflectance at six wavelengths in the visible spectral domain corresponding to MODIS ocean color sensor. This algorithm allows the separation of colored detrital matter (CDM) into CDOM and non-algal particles (NAP) through the determination of NAP absorption using an empirical relationship between NAP absorption and particle backscattering coefficients. Evaluation using independent datasets, which were not used for developing the algorithm, showed that CDOM absorption can be estimated accurately to within an uncertainty of 35% and 50% for oceanic and coastal waters, respectively. A previous paper (Matsuoka et al., 2012) showed that dissolved organic carbon (DOC) concentrations were tightly correlated with CDOM absorption in our study area (r2 = 0.97). By combining the CDOM absorption algorithm together with the DOC versus CDOM relationship, it is now possible to estimate DOC concentrations in the near-surface layer of the southern Beaufort Sea using satellite ocean color data. DOC concentrations in the surface waters were estimated using MODIS ocean color data, and the estimates showed reasonable values compared to in situ measurements. We propose a routine and near real-time method for deriving DOC concentrations from space, which may open the way to an estimate of DOC budgets for Arctic coastal waters.

  20. Double Compressions of Atmospheric Depth by Geopotential Tendency, Vorticity, and Atmospheric Boundary Layer Affected Abrupt High Particulate Matter Concentrations at a Coastal City for a Yellow Dust Period in October

    Directory of Open Access Journals (Sweden)

    Hyo Choi

    2014-01-01

    Full Text Available Using GRIMM-aerosol sampler, NOAA-HYSPLIT model, and 3D-WRF-3.3 model, the transportation of dusts from Gobi Desert toward Gangneung city, Korea was investigated from 09:00 LST October 27 to 04:00 LST October 28, 2003. Maximum PM10 (PM2.5, PM1 concentration was detected with 3.8 (3.4, 14.1 times higher magnitude than one in non-Yellow Dust period. The combination of dusts transported from the desert under westerly wind with particulate matters and gases from vehicles on the road of the city caused high PM concentrations near the ground surface at 09:00 LST and their maxima at 17:00 LST near sunset with further pollutants from heating boilers in the resident area. Positive geopotential tendency at the 500 hPa level of the city (∂Φ/∂t; m day−1 corresponding to negative vorticity of -4×10-5 sec−1 (-2.5×10-5 sec−1 at 0900 LST (21:00 LST; at night was +83 m day−1 (+30 m day−1 and it caused atmospheric depth between 500 hPa level and the ground surface to be vertically expanded. However, its net reduction to −53 m/12 hrs until 21:00 LST indicated synoptic-scale atmospheric layer to be vertical shrunken, resulting in the increase of PM concentrations at 17:00 LST. Simultaneously, much shallower microscale stable nocturnal surface inversion layer (NSIL than daytime thermal internal boundary layer induced particulate matters to be merged inside the NSIL, resulting in maximum PM concentrations at 17:00 LST.

  1. Estimating absorption coefficients of colored dissolved organic matter (CDOM using a semi-analytical algorithm for southern Beaufort Sea waters: application to deriving concentrations of dissolved organic carbon from space

    Directory of Open Access Journals (Sweden)

    A. Matsuoka

    2013-02-01

    Full Text Available A series of papers have suggested that freshwater discharge, including a large amount of dissolved organic matter (DOM, has increased since the middle of the 20th century. In this study, a semi-analytical algorithm for estimating light absorption coefficients of the colored fraction of DOM (CDOM was developed for southern Beaufort Sea waters using remote sensing reflectance at six wavelengths in the visible spectral domain corresponding to MODIS ocean color sensor. This algorithm allows the separation of colored detrital matter (CDM into CDOM and non-algal particles (NAP through the determination of NAP absorption using an empirical relationship between NAP absorption and particle backscattering coefficients. Evaluation using independent datasets, which were not used for developing the algorithm, showed that CDOM absorption can be estimated accurately to within an uncertainty of 35% and 50% for oceanic and coastal waters, respectively. A previous paper (Matsuoka et al., 2012 showed that dissolved organic carbon (DOC concentrations were tightly correlated with CDOM absorption in our study area (r2 = 0.97. By combining the CDOM absorption algorithm together with the DOC versus CDOM relationship, it is now possible to estimate DOC concentrations in the near-surface layer of the southern Beaufort Sea using satellite ocean color data. DOC concentrations in the surface waters were estimated using MODIS ocean color data, and the estimates showed reasonable values compared to in situ measurements. We propose a routine and near real-time method for deriving DOC concentrations from space, which may open the way to an estimate of DOC budgets for Arctic coastal waters.

  2. Dark Matter

    Directory of Open Access Journals (Sweden)

    Einasto J.

    2011-06-01

    Full Text Available I give a review of the development of the concept of dark matter. The dark matter story passed through several stages from a minor observational puzzle to a major challenge for theory of elementary particles. Modern data suggest that dark matter is the dominant matter component in the Universe, and that it consists of some unknown non-baryonic particles. Dark matter is the dominant matter component in the Universe, thus properties of dark matter particles determine the structure of the cosmic web.

  3. Landsat-Based Long-Term Monitoring of Total Suspended Matter Concentration Pattern Change in the Wet Season for Dongting Lake, China

    Directory of Open Access Journals (Sweden)

    Zhubin Zheng

    2015-10-01

    Full Text Available Assessing the impacts of environmental change and anthropogenic activities on the historical and current total suspended matter (TSM pattern in Dongting Lake, China, is a large challenge. We addressed this challenge by using more than three decades of Landsat data. Based on in situ measurements, we developed an algorithm based on the near-infrared (NIR band to estimate TSM in Dongting Lake. The algorithm was applied to Landsat images to derive TSM distribution maps from 1978 to 2013 in the wet season, revealing significant inter-annual and spatial variability. The relationship of TSM to water level, precipitation, and wind speed was analyzed, and we found that: (1 sand mining areas usually coincide with regions that have high TSM levels in Dongting Lake; (2 water level and seven-day precipitation were both important to TSM variation, but no significant relationship was found between TSM and wind speed or other meteorological data; (3 the increased level of sand mining in response to rapid economic growth has deeply influenced the TSM pattern since 2000 due to the resuspension of sediment; and (4 TSM variation might be associated with policy changes regarding the management of sand mining; it might also be affected by lower water levels caused by the impoundment of the Three Gorges Dam since 2000.

  4. The effect of grain size and surface area on organic matter, lignin and carbohydrate concentration, and molecular compositions in Peru Margin sediments

    Science.gov (United States)

    Bergamaschi, Brian A.; Tsamakis, Elizabeth; Keil, Richard G.; Eglinton, Timothy I.; Montluçon, Daniel B.; Hedges, John I.

    1997-03-01

    A C-rich sediment sample from the Peru Margin was sorted into nine hydrodynamically-determined grain size fractions to explore the effect of grain size distribution and sediment surface area on organic matter content and composition. The neutral monomeric carbohydrate composition, lignin oxidation product yields, total organic carbon, and total nitrogen contents were determined independently for each size fraction, in addition to sediment surface area and abundance of biogenic opal. The percent organic carbon and percent total nitrogen were strongly related to surface area in these sediments. In turn, the distribution of surface area closely followed mass distribution among the textural size classes, suggesting hydrodynamic controls on grain size also control organic carbon content. Nevertheless, organic compositional distinctions were observed between textural size classes. Total neutral carbohydrate yields in the Peru Margin sediments were found to closely parallel trends in total organic carbon, increasing in abundance among grain size fractions in proportion to sediment surface area. Coincident with the increases in absolute abundance, rhamnose and mannose increased as a fraction of the total carbohydrate yield in concert with surface area, indicating these monomers were preferentially represented in carbohydrates associated with surfaces. Lignin oxidation product yields varied with surface area when normalized to organic carbon, suggesting that the terrestrially-derived component may be diluted by sorption of marine derived material. Lignin-based parameters suggest a separate source for terrestrially derived material associated with sand-size material as opposed to that associated with silts and clays.

  5. Short-term population-based and spatiotemporal nonlinear concentration-response associations between fine particulate matter and children's respiratory clinic visits

    Science.gov (United States)

    Yu, Hwa-Lung; Chien, Lung-Chang

    2014-05-01

    Advert health impacts associated with the PM2.5 exposure have been confirmed in mortality and cardiovascular diseases; however, findings of the influence of PM2.5 on respiratory diseases investigated among previous studies are still inconsistent. We investigated the short-term population-based associations between the respiratory clinic visits of children population and the PM2.5 exposure levels with considering both the spatiotemporal distributions of the ambient pollution and clinic visit data. We applied a spatiotemporal structured additive regression model to examine the concentration-response (C-R) association between daily children's respiratory clinic visits and PM2.5 concentrations. The analysis was performed separately on the four selected respiratory disease categories of the population-based dataset, obtained from Taiwan National Health Insurance database, covering the 41 districts in Taipei area during the period of 2005 to 2007. This study reveals a strong nonlinear C-R pattern that the PM2.5 increment can significantly affect respiratory health at PM2.5 concentration ≤ 18.17µg/m3 for both preschool children and schoolchildren. The elevated risks are especially present in the category of acute respiratory infections. PM2.5 increase is mostly non-significant to the more severe respiratory diseases, e.g., COPD and pneumonia, over the ranges of 8.85-92.45µg/m3. The significantly higher relative rate of respiratory clinic visit most likely concentrated at populated areas. We highlight the nonlinearity of the respiratory health impacts of PM2.5 on children's populations from the first study, to our knowledge, to investigate this population-based association. The strong nonlinearity can possibly cause the inconsistency of PM2.5 health impact assessments with linear assumptions.

  6. Air oxidation of samples from different clay formations of East Paris basin: quantitative and qualitative consequences on the dissolved organic matter

    International Nuclear Information System (INIS)

    Blanchart, Pascale; Faure, Pierre; Michels, Raymond; Parant, Stephane

    2012-01-01

    Document available in extended abstract form only. During the excavation and the building of an underground research laboratory in clay geological formations, exposure to air is one of the most important parameters affecting the composition of fossil organic matter. Indeed the net effect of air oxidation of the organic matter is enrichment in oxygen and carbon combined with a loss of hydrogen. Effluents formed are CO 2 and water as well as the liberation of hydrocarbons. This process may have an impact on water chemistry of the clay, especially on the quantity and composition of Dissolved Organic Matter (DOM). The clays studied were the following and may be distinguished on the basis of their organic matter content: - The Callovo-Oxfordian argillite, collected in the Bure Underground Research Laboratory (Meuse, France), which contains a mixture of type II and III kerogen; - The Toarcian shales of East Paris Basin collected from drilling EST 204 (Meuse, France) contains type II kerogen; - The Kimmeridgian shales of East Paris Basin collected from drilling HTM 102 (Meuse, France) also contains type II kerogen. The powdered clay samples were oxidized in a ventilated oven at 100 C under air flow during 2, 256, 512 and 1088 hours for Callovo-Oxfordian samples and during 512 and 2048 hours for Toarcian and Kimmeridgian samples. The DOM of each sample was extracted by soxhlet using pure water. Different analyses were carried out: - Quantitative evolution of DOM with the oxidation process; - Evolution of several chemical parameters of DOM with oxidation using molecular analyses (PyGC-MS) molecular weight distribution (GPC-HPLC) as well as spectroscopic measurements (3D-Fluorescence). Increasing oxidation induces an increase of DOC values for all samples. Also, Changes in the chemical composition of the DOM are observed: decrease in the molecular weight range; enrichment in acidic functional groups (alkane-dioic acids, alkanoic acids, aromatics poly acids). Moreover the

  7. Characteristics of lead isotope ratios and elemental concentrations in PM 10 fraction of airborne particulate matter in Shanghai after the phase-out of leaded gasoline

    Science.gov (United States)

    Zheng, Jian; Tan, Mingguang; Shibata, Yasuyuki; Tanaka, Atsushi; Li, Yan; Zhang, Guilin; Zhang, Yuanmao; Shan, Zuci

    The stable lead (Pb) isotope ratios and the concentrations of 23 elements, including heavy metals and toxic elements, were measured in the PM 10 airborne particle samples collected at seven monitoring sites in Shanghai, China, to evaluate the current elemental compositions and local airborne Pb isotope ratio characteristics. Some source-related samples, such as cement, coal and oil combustion dust, metallurgic dust, vehicle exhaust particles derived from leaded gasoline and unleaded gasoline, and polluted soils were analyzed for their Pb content and isotope ratio and compared to those observed in PM 10 samples. Airborne Pb concentration ranged from 167 to 854 ng/m 3 in the seven monitored sites with an average of 515 ng/m 3 in Shanghai, indicating that a high concentration of Pb remains in the air after the phasing out of leaded gasoline. Lead isotopic compositions in airborne particles ( 207Pb/ 206Pb, 0.8608±0.0018; 208Pb/ 206Pb, 2.105±0.005) are clearly distinct from the vehicle exhaust particles ( 207Pb/ 206Pb, 0.8854±0.0075; 208Pb/ 206Pb, 2.145±0.006), suggesting that the automotive lead is not currently the major component of Pb in the air. By using a binary mixing equation, a source apportionment based on 207Pb/ 206Pb ratios, indicates that the contribution from automotive emission to the airborne Pb is around 20%. The Pb isotope ratios obtained in the source-related samples confirmed that the major emission sources are metallurgic dust, coal combustion, and cement.

  8. Gender Disparity in Lung Function Abnormalities among a Population Exposed to Particulate Matter Concentration in Ambient Air in the National Capital Region, India

    Directory of Open Access Journals (Sweden)

    Chandrasekharan Nair Kesavachandran

    2015-01-01

    Conclusions. Since the women in this study were non-smokers, the PM in ambient air can be considered to be the major reason for the decline in lung function. The sources of PM pollutants in the study locations are large scale infrastructural development activities such as building and road construction activities. Narrowed lung airways can alter the airway caliber or resistance and flow rates proportional to the airway radius, especially in smaller airways. The present study suggests the need for policy makers and stake holders to take the necessary steps to identify PM sources and reduce the emissions of PM concentrations in ambient air.

  9. Solid Matter

    CERN Document Server

    Angelo, Joseph A

    2011-01-01

    Supported by a generous quantity of full-color illustrations and interesting sidebars, Solid Matter introduces the basic characteristics and properties of solid matter. It briefly describes the cosmic connection of the elements, leading readers through several key events in human pre-history that resulted in more advanced uses of matter in the solid state. Chapters include:. -Solid Matter: An Initial Perspective. -Physical Behavior of Matter. -The Gravity of Matter. -Fundamentals of Materials Science. -Rocks and Minerals. -Metals. -Building Materials. -Carbon Earth's Most Versatile Element. -S

  10. Catalytic generation of methane at 60-100 °C and 0.1-300 MPa from source rocks containing kerogen Types I, II, and III

    Science.gov (United States)

    Wei, Lin; Schimmelmann, Arndt; Mastalerz, Maria; Lahann, Richard W.; Sauer, Peter E.; Drobniak, Agnieszka; Strąpoć, Dariusz; Mango, Frank D.

    2018-06-01

    Low temperature (60 and 100 °C) and long-term (6 months to 5 years) heating of pre-evacuated and sterilized shales and coals containing kerogen Types I (Mahogany Shale), II (Mowry Shale and New Albany Shale), and III (Springfield Coal and Wilcox Lignite) with low initial maturities (vitrinite reflectance Ro 0.39-0.62%) demonstrates that catalytically generated hydrocarbons may explain the occurrence of some non-biogenic natural gas accumulations where insufficient thermal maturity contradicts the conventional thermal cracking paradigm. Extrapolation of the observed rate of catalytic methanogenesis in the laboratory suggests that significant amounts of sedimentary organic carbon can be converted to relatively dry natural gas over tens of thousands of years in sedimentary basins at temperatures as low as 60 °C. Our laboratory experiments utilized source rock (shale and coal) chips sealed in gold and Pyrex® glass tubes in the presence of hydrogen-isotopically contrasting waters. Parallel heating experiments applied hydrostatic pressures from 0.1 to 300 MPa. Control experiments constrained the influence of pre-existing and residual methane in closed pores of rock chips that was unrelated to newly generated methane. This study's experimental methane yields at 60 and 100 °C are 5-11 orders of magnitude higher than the theoretically predicted yields from kinetic models of thermogenic methane generation, which strongly suggests a contribution of catalytic methanogenesis. Higher temperature, longer heating time, and lower hydrostatic pressure enhanced catalytic methanogenesis. No clear relationships were observed between kerogen type or total organic carbon content and methane yields via catalysis. Catalytic methanogenesis was strongest in Mowry Shale where methane yields at 60 °C amounted to ∼2.5 μmol per gram of organic carbon after one year of hydrous heating at ambient pressure. In stark contrast to the earlier findings of hydrogen isotopic exchange between

  11. Chemical and nanometer-scale structure of kerogen and its change during thermal maturation investigated by advanced solid-state 13C NMR spectroscopy

    Science.gov (United States)

    Mao, J.; Fang, X.; Lan, Y.; Schimmelmann, A.; Mastalerz, Maria; Xu, L.; Schmidt-Rohr, K.

    2010-01-01

    We have used advanced and quantitative solid-state nuclear magnetic resonance (NMR) techniques to investigate structural changes in a series of type II kerogen samples from the New Albany Shale across a range of maturity (vitrinite reflectance R0 from 0.29% to 1.27%). Specific functional groups such as CH3, CH2, alkyl CH, aromatic CH, aromatic C-O, and other nonprotonated aromatics, as well as "oil prone" and "gas prone" carbons, have been quantified by 13C NMR; atomic H/C and O/C ratios calculated from the NMR data agree with elemental analysis. Relationships between NMR structural parameters and vitrinite reflectance, a proxy for thermal maturity, were evaluated. The aromatic cluster size is probed in terms of the fraction of aromatic carbons that are protonated (???30%) and the average distance of aromatic C from the nearest protons in long-range H-C dephasing, both of which do not increase much with maturation, in spite of a great increase in aromaticity. The aromatic clusters in the most mature sample consist of ???30 carbons, and of ???20 carbons in the least mature samples. Proof of many links between alkyl chains and aromatic rings is provided by short-range and long-range 1H-13C correlation NMR. The alkyl segments provide most H in the samples; even at a carbon aromaticity of 83%, the fraction of aromatic H is only 38%. While aromaticity increases with thermal maturity, most other NMR structural parameters, including the aromatic C-O fractions, decrease. Aromaticity is confirmed as an excellent NMR structural parameter for assessing thermal maturity. In this series of samples, thermal maturation mostly increases aromaticity by reducing the length of the alkyl chains attached to the aromatic cores, not by pronounced growth of the size of the fused aromatic ring clusters. ?? 2010 Elsevier Ltd. All rights reserved.

  12. Concentration dynamics of soluble matter in a large water supply system and its implication as regards the propagation of accidental pollution in the system, using isotope techniques

    International Nuclear Information System (INIS)

    Gilath, C.

    1977-04-01

    The concentration dynamics of conservative pollutants in the water conveyance scheme of the Israel National Water Carrier was investigated by means of radioactive tracer techniques. The mixing behaviour of three shallow lakes is predominantly reflected by wind-induced currents and it can be described by a model consisting of a time delay in series with one or two time constants. The parameters of these mixed region models were found under different operational and environmental conditions. The turbulent dispersion was measured for two types of open channels. The computed values of the dispersion coefficient were close to experimental findings, confirming the agreement of the observed dispersion with Taylor's theory. Complete mixing was observed at a certain distance from the injection point, beyond which the dispersion coefficient becomes constant

  13. Speech Matters

    DEFF Research Database (Denmark)

    Hasse Jørgensen, Stina

    2011-01-01

    About Speech Matters - Katarina Gregos, the Greek curator's exhibition at the Danish Pavillion, the Venice Biannual 2011.......About Speech Matters - Katarina Gregos, the Greek curator's exhibition at the Danish Pavillion, the Venice Biannual 2011....

  14. Memory Matters

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Memory Matters KidsHealth / For Kids / Memory Matters What's in ... of your complex and multitalented brain. What Is Memory? When an event happens, when you learn something, ...

  15. Dark Matter

    Indian Academy of Sciences (India)

    What You See Ain't What. You Got, Resonance, Vol.4,. No.9,1999. Dark Matter. 2. Dark Matter in the Universe. Bikram Phookun and Biman Nath. In Part 11 of this article we learnt that there are compelling evidences from dynamics of spiral galaxies, like our own, that there must be non-luminous matter in them. In this.

  16. Geochemical study of the insoluble organic material (kerogen) in the Oklo uranium ore and the associated Francevillian schists

    International Nuclear Information System (INIS)

    Vandenbroucke, M.; Rouzaud, J.N.; Oberlin, A.

    1978-01-01

    The purpose of this study was to describe the organic material associated with uranium ore and ore transformations undergone by it, in terms of the following problems: (1) In the natural reactor zones, evolution of the organic material in the core and as a function of the distance away from it; (2) Comparison of organic materials from a rich and a poor ore; (3) Intercomparison of organic materials in the dispersed and concentrated state; (4) Comparison of organic materials in the uranium ore zones and in the adjacent non-mineralized Francevillian. The organic material from the reactor core could not be isolated by the normal techniques of treatment with acid. It is found in other cases that the organic material is oxidized in the uranium-bearing sediments and that the nearer to the reaction zone, the greater the oxidation, irrespective of the state of dispersion of the organic material in the rock. The uranium content does not affect this phenomenon, which is attributed to the action of the water raised to a high temperature in the vicinity of the reaction zones. On the basis of the present distribution of organic material and uranium the authors suggest a pattern for the formation of the deposit that would take into account localization of the ore in the sandstones and the part played by organic material in the accumulation process. (author)

  17. Is ozonation environmentally benign for reverse osmosis concentrate treatment? Four-level analysis on toxicity reduction based on organic matter fractionation.

    Science.gov (United States)

    Weng, Jingxia; Jia, Huichao; Wu, Bing; Pan, Bingcai

    2018-01-01

    Ozonation is a promising option to treat reverse osmosis concentrate (ROC). However, a systematic understanding and assessment of ozonation on toxicity reduction is insufficient. In this study, ROC sampled from a typical industrial park wastewater treatment plant of China was fractionated into hydrophobic acid (HOA), hydrophobic base (HOB), hydrophobic neutral (HON), and hydrophilic fraction (HI). Systematic bioassays covering bacteria, algae, fish, and human cell lines were conducted to reveal the role of ozonation in toxicity variation of the four ROC fractions. HOA in the raw ROC exhibited the highest toxicity, followed by HON and HI. Ozonation significantly reduced total organic carbon (TOC) and UV 254 values in HOA, HON, and HI and their toxicity except in HOB. Correlation analysis indicated that chemical data (TOC and UV 254 ) of HOA and HON correlated well with their toxicities; however, poor correlations were observed for HOB and HI, suggesting that a battery of toxicity assays is necessary. This study indicates that TOC reduction during ozonation could not fully reflect the toxicity issue, and toxicity assessment is required in conjunction with the chemical data to evaluate the effectiveness of ozonation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Effect of organic-matter type and thermal maturity on methane adsorption in shale-gas systems

    Science.gov (United States)

    Zhang, Tongwei; Ellis, Geoffrey S.; Ruppel, Stephen C.; Milliken, Kitty; Yang, Rongsheng

    2012-01-01

    A series of methane (CH4) adsorption experiments on bulk organic rich shales and their isolated kerogens were conducted at 35 °C, 50 °C and 65 °C and CH4 pressure of up to 15 MPa under dry conditions. Samples from the Eocene Green River Formation, Devonian–Mississippian Woodford Shale and Upper Cretaceous Cameo coal were studied to examine how differences in organic matter type affect natural gas adsorption. Vitrinite reflectance values of these samples ranged from 0.56–0.58 %Ro. In addition, thermal maturity effects were determined on three Mississippian Barnett Shale samples with measured vitrinite reflectance values of 0.58, 0.81 and 2.01 %Ro. For all bulk and isolated kerogen samples, the total amount of methane adsorbed was directly proportional to the total organic carbon (TOC) content of the sample and the average maximum amount of gas sorption was 1.36 mmol of methane per gram of TOC. These results indicate that sorption on organic matter plays a critical role in shale-gas storage. Under the experimental conditions, differences in thermal maturity showed no significant effect on the total amount of gas sorbed. Experimental sorption isotherms could be fitted with good accuracy by the Langmuir function by adjusting the Langmuir pressure (PL) and maximum sorption capacity (Γmax). The lowest maturity sample (%Ro = 0.56) displayed a Langmuir pressure (PL) of 5.15 MPa, significantly larger than the 2.33 MPa observed for the highest maturity (%Ro > 2.01) sample at 50 °C. The value of the Langmuir pressure (PL) changes with kerogen type in the following sequence: type I > type II > type III. The thermodynamic parameters of CH4 adsorption on organic rich shales were determined based on the experimental CH4 isotherms. For the adsorption of CH4 on organic rich shales and their isolated kerogen, the heat of adsorption (q) and the standard entropy (Δs0) range from 7.3–28.0 kJ/mol and from −36.2 to −92.2 J/mol/K, respectively.

  19. The palaeoenvironmental implications of carbonate petrography, kerogen distribution and carbon and oxygen isotope variations in the early Proterozoic transition from Campbellrand limestone to Kuruman iron-formation deposition in Griqualand West

    International Nuclear Information System (INIS)

    Beukes, N.J.; Klein, C.; Kaufman, A.J.; Hayes, J.M.

    1990-01-01

    The Griqualand West area of the Transvaal basin in South Africa offers a unique opportunity to study the relationships between the deposition of limestone and iron-formation. The stratigraphic sequence includes the transition from microbialaminated Campbellrand carbonates to the conformably Kuruman iron formation composed mainly of microbanded iron-formation. The relationships between carbonate mineral paragenesis, kerogen abundance, and isotopic compositions of carbon and oxygen for the same drill core samples are reported. The significance of whole rock carbon-isotopic compositions of iron-formations relative to those of limestones and dolomites are explored. 6 refs

  20. A global analysis of the concentration and dynamics of non-structural carbohydrates in plants: does it matter under global change? (Invited)

    Science.gov (United States)

    Sala, A.; Martínez-Vilalta, J.; Asencio, M.; Lloret, F.; Palacio, S.; Galiano, L.; Hoch, G.; Piper, F.

    2013-12-01

    Forests store significant amounts of C globally and recent reports of forest mortality world-wide have generated strong concern. Evidence suggests that increasing drought associated with climate change is a primary cause of tree stress and subsequent mortality. This has generated an urgent need to predict how forests will cope with increasing stress. Storage of non-structural C compounds (NSC, compounds not permanently invested in structural biomass that can later be used to support diverse plant functions) is critical for survival during periods when C assimilation does not meet demand. However, remarkable knowledge gaps exist to accurately predict plant growth and survival under climate change. Although trees accumulate relatively large pools of NSC, there is a strong debate on how these pools build up over time. On the one hand, it is frequently assumed that the build- up of NSC in trees occurs when supply via photosynthesis exceeds overall demands. If so, the abundant NSC pools in trees reflect an overabundance of C in the long term. An alternative explanation is that trees regulate NSC storage to maintain sufficient pools to cope with asynchronies between demand and supply and with stresses that long lived plants inevitably experience during their life time. However, our understanding of whether and how trees regulate storage in the long term is minimal. Here, we assembled a new global database to examine broad patterns of seasonal NSC variation across organs, life forms and biomes, and the degree to which NSC storage is depleted in plants under a wide range of natural conditions. We compiled seasonal data (at least three measurements over a minimum of four months) for ca. 200 wild species under natural conditions. On average, NSC account for ca. 8-10% of dry plant biomass. NSC and starch concentrations do not vary significantly with biome, but soluble sugars (SS) in plants from Mediterranean biomes are higher than in temperate or tropical biomes. On average

  1. Multi-technical approach to characterize the dissolved organic matter from clay-stone

    International Nuclear Information System (INIS)

    Blanchart, Pascale; Michels, Raymond; Faure, Pierre; Parant, Stephane; Bruggeman, Christophe; De Craen, Mieke

    2012-01-01

    Document available in extended abstract form only. Currently, different clay formations (Boom Clay, Callovo-Oxfordian argilites, Opalinus Clay, Toarcian shales...) are studied as reference host rocks for methodological studies on the geological disposal of high-level and long-lived radioactive waste. While a significant effort is being done on the characterization of the mineral composition and the reactivity of the clays as barriers, the occurrence of organic matter, even in low proportion cannot be neglected. The organic matter appears as gas (C 1 -C 4 as identified in the Bure underground facilities), as solid (kerogen), as hydrocarbon liquids (free hydrocarbons within the kerogen or adsorbed on minerals) as well as in the aqueous phase (Dissolved Organic Matter - DOM). DOM raises specific interest, as it may have complexation properties towards metals and rare earth elements and is potentially mobile. Therefore, it is important to characterize the DOM as part of a study of feasibility of geological disposal. In this study, four host rocks were studied: - The Callovo-Oxfordian shales of Bure Underground Research Laboratory (Meuse, France); - The Opalinus Clay of Mont Terri Underground Research Laboratory (Switzerland); - The Toarcian shales of Tournemire (Aveyron, France); - The Boom Clay formation studied in The HADES Underground Research Laboratory (Mol, Belgium). Organic matter characteristics vary upon formation in terms of (i) origin (mainly marine type II; mixtures of marine type II and higher plants type III organic matter often poorly preserved), (ii) TOC contents, (iii) thermal maturity (for instance, Opalinus Clay and Toarcian shales are more mature and have poor oxygen content compare to Callovo-Oxfordian shales and Boom Clay). These differences in organic matter quality may have an influence on the quantity and the quality of DOM. The DOM of the rocks was isolated by Soxhlet extraction using pure water. A quantitative and qualitative multi

  2. Concentrations of Platinum Group Elements (Pt, Pd, Rh in Airborne Particulate Matter (PM2.5 and PM10-2.5 Collected at Selected Canadian Urban Sites: a Case Study

    Directory of Open Access Journals (Sweden)

    Celo V.

    2013-04-01

    Full Text Available Increasing environmental concentrations of platinum group elements (PGEs, in particular platinum (Pt, palladium (Pd and rhodium (Rh, from catalytic converters has been reported worldwide. Initially it was believed that the emitted PGEs remain in the roadside environment, but recent studies have shown that fine PGE-containing particles can be transported and distributed at regional and long-range levels. Therefore, the monitoring of PGEs in airborne particulate matter (PM is important for the estimation of potential risks to human health and to the ecosystem. The aim of this study is to present the first results from an analysis on the concentration and distribution of Pt, Pd and Rh in PM collected on Teflon filters at two selected urban sites (Toronto, Ontario; Edmonton, Alberta collected within the Canadian National Air Pollution Surveillance (NAPS network. In this work, a quadruple inductively coupled plasma mass spectrometry (ICP-MS, combined with microwave assisted acid digestion using aqua regia was used. A cation exchange separation was used to alleviate the matrix-induced spectral and nonspectral interferences prior to ICP-MS analysis. To obtain sufficient material needed for PGEs analysis, fine PM (particles with aerodynamic diameter less than 2.5 mm; PM2.5 and coarse PM (with aerodynamic diameter between 2.5 and 10 mm; PM10-2.5 samples were combined into composite samples on a seasonal basis. The obtained results will be discussed and compared with literature data.

  3. D matter

    International Nuclear Information System (INIS)

    Shiu, Gary; Wang Liantao

    2004-01-01

    We study the properties and phenomenology of particlelike states originating from D branes whose spatial dimensions are all compactified. They are nonperturbative states in string theory and we refer to them as D matter. In contrast to other nonperturbative objects such as 't Hooft-Polyakov monopoles, D-matter states could have perturbative couplings among themselves and with ordinary matter. The lightest D particle (LDP) could be stable because it is the lightest state carrying certain (integer or discrete) quantum numbers. Depending on the string scale, they could be cold dark matter candidates with properties similar to that of WIMPs or wimpzillas. The spectrum of excited states of D matter exhibits an interesting pattern which could be distinguished from that of Kaluza-Klein modes, winding states, and string resonances. We speculate about possible signatures of D matter from ultrahigh energy cosmic rays and colliders

  4. Dark Matter

    International Nuclear Information System (INIS)

    Holt, S. S.; Bennett, C. L.

    1995-01-01

    These proceedings represent papers presented at the Astrophysics conference in Maryland, organized by NASA Goddard Space Flight Center and the University of Maryland. The topics covered included low mass stars as dark matter, dark matter in galaxies and clusters, cosmic microwave background anisotropy, cold and hot dark matter, and the large scale distribution and motions of galaxies. There were eighty five papers presented. Out of these, 10 have been abstracted for the Energy Science and Technology database

  5. Lectures on dark matter

    International Nuclear Information System (INIS)

    Seljak, U.

    2001-01-01

    These lectures concentrate on evolution and generation of dark matter perturbations. The purpose of the lectures is to present, in a systematic way, a comprehensive review of the cosmological parameters that can lead to observable effects in the dark matter clustering properties. We begin by reviewing the relativistic linear perturbation theory formalism. We discuss the gauge issue and derive Einstein's and continuity equations for several popular gauge choices. We continue by developing fluid equations for cold dark matter and baryons and Boltzmann equations for photons, massive and massless neutrinos. We then discuss the generation of initial perturbations by the process of inflation and the parameters of that process that can be extracted from the observations. Finally we discuss evolution of perturbations in various regimes and the imprint of the evolution on the dark matter power spectrum both in the linear and in the nonlinear regime. (author)

  6. Lectures on dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Seljak, U [Department of Physics, Princeton University, Princeton, NJ (United States)

    2001-11-15

    These lectures concentrate on evolution and generation of dark matter perturbations. The purpose of the lectures is to present, in a systematic way, a comprehensive review of the cosmological parameters that can lead to observable effects in the dark matter clustering properties. We begin by reviewing the relativistic linear perturbation theory formalism. We discuss the gauge issue and derive Einstein's and continuity equations for several popular gauge choices. We continue by developing fluid equations for cold dark matter and baryons and Boltzmann equations for photons, massive and massless neutrinos. We then discuss the generation of initial perturbations by the process of inflation and the parameters of that process that can be extracted from the observations. Finally we discuss evolution of perturbations in various regimes and the imprint of the evolution on the dark matter power spectrum both in the linear and in the nonlinear regime. (author)

  7. Individual-Level Concentrations of Fine Particulate Matter Chemical Components and Subclinical Atherosclerosis: A Cross-Sectional Analysis Based on 2 Advanced Exposure Prediction Models in the Multi-Ethnic Study of Atherosclerosis

    Science.gov (United States)

    Kim, Sun-Young; Sheppard, Lianne; Kaufman, Joel D.; Bergen, Silas; Szpiro, Adam A.; Larson, Timothy V.; Adar, Sara D.; Diez Roux, Ana V.; Polak, Joseph F.; Vedal, Sverre

    2014-01-01

    Long-term exposure to outdoor particulate matter with an aerodynamic diameter less than or equal to 2.5 µm (PM2.5) has been associated with cardiovascular morbidity and mortality. The chemical composition of PM2.5 that may be most responsible for producing these associations has not been identified. We assessed cross-sectional associations between long-term concentrations of PM2.5 and 4 of its chemical components (sulfur, silicon, elemental carbon, and organic carbon (OC)) and subclinical atherosclerosis, measured as carotid intima-media thickness (CIMT) and coronary artery calcium, between 2000 and 2002 among 5,488 Multi-Ethnic Study of Atherosclerosis participants residing in 6 US metropolitan areas. Long-term concentrations of PM2.5 components at participants' homes were predicted using both city-specific spatiotemporal models and a national spatial model. The estimated differences in CIMT associated with interquartile-range increases in sulfur, silicon, and OC predictions from the spatiotemporal model were 0.022 mm (95% confidence interval (CI): 0.014, 0.031), 0.006 mm (95% CI: 0.000, 0.012), and 0.026 mm (95% CI: 0.019, 0.034), respectively. Findings were generally similar using the national spatial model predictions but were often sensitive to adjustment for city. We did not find strong evidence of associations with coronary artery calcium. Long-term concentrations of sulfur and OC, and possibly silicon, were associated with CIMT using 2 distinct exposure prediction modeling approaches. PMID:25164422

  8. Dark Matter

    International Nuclear Information System (INIS)

    Bashir, A.; Cotti, U.; De Leon, C. L.; Raya, A; Villasenor, L.

    2008-01-01

    One of the biggest scientific mysteries of our time resides in the identification of the particles that constitute a large fraction of the mass of our Universe, generically known as dark matter. We review the observations and the experimental data that imply the existence of dark matter. We briefly discuss the properties of the two best dark-matter candidate particles and the experimental techniques presently used to try to discover them. Finally, we mention a proposed project that has recently emerged within the Mexican community to look for dark matter

  9. Dry matter digestibility of roughages and concentrates determined “in vitro” procedures Digestibilidade da matéria seca de alimentos volumosos e concentrados determinada por procedimentos "in vitro"

    Directory of Open Access Journals (Sweden)

    Rui da Silva Verneque

    2011-09-01

    Full Text Available The aim of this work was to compare the values of in vitro dry matter digestibility of six classes of concentrates and roughages feeds, determined by the two-stage technique carried in individual digestion tubes or using an automatized equipment of fermentation (filter bag technique, FBT. In the second digestion stage of the technique it was also evaluated the effect of pepsin acid solution and the reflux with neutral detergent solution on the in vitro dry matter digestibility. For both studies the experimental design was completely randomized with a 2 x 6 factorial arrangement (in vitro procedures x food classes. The IVDMD values determined in tubes were close to those found by others authors and lower than those obtained by the filter bag technique. Standard deviation of in vitro dry matter digestibility means were, in general, lower when the individual tubes method were used. The procedure using reflux with neutral detergent was less expensive and time-consuming, and yield similar results when compared to those using the acidified pepsin digestion methodology. The apparent overestimated values of in vitro dry matter digestibility observed in the filter bag technique suggests that the recommendation of the automatized equipment will be dependent of new studies, with emphasis to the material used to make the incubation bags.Objetivou-se neste trabalho comparar valores de digestibilidade in vitro da matéria seca de seis classes de alimentos concentrados e volumosos, determinados pelo método de dois estágios, realizado em tubos individuais ou em equipamento automatizado de fermentação (incubadora in vitro. No segundo estágio da análise foi adicionalmente avaliado o efeito sobre a digestibilidade in vitro da matéria seca da utilização de solução ácida de pepsina ou do refluxo em solução de detergente neutro. Para ambos os estudos utilizou-se delineamento inteiramente casualizado, em esquema fatorial 2 x 6 (procedimentos in vitro x

  10. Gaseous Matter

    CERN Document Server

    Angelo, Joseph A

    2011-01-01

    aseous Matter focuses on the many important discoveries that led to the scientific interpretation of matter in the gaseous state. This new, full-color resource describes the basic characteristics and properties of several important gases, including air, hydrogen, helium, oxygen, and nitrogen. The nature and scope of the science of fluids is discussed in great detail, highlighting the most important scientific principles upon which the field is based. Chapters include:. Gaseous Matter An Initial Perspective. Physical Characteristics of Gases. The Rise of the Science of Gases. Kinetic Theory of

  11. Biogenicity and Syngeneity of Organic Matter in Ancient Sedimentary Rocks: Recent Advances in the Search for Evidence of Past Life

    Energy Technology Data Exchange (ETDEWEB)

    Oehler, Dorothy Z.; Cady, Sherry L.

    2014-12-01

    he past decade has seen an explosion of new technologies for assessment of biogenicity and syngeneity of carbonaceous material within sedimentary rocks. Advances have been made in techniques for analysis of in situ organic matter as well as for extracted bulk samples of soluble and insoluble (kerogen) organic fractions. The in situ techniques allow analysis of micrometer-to-sub-micrometer-scale organic residues within their host rocks and include Raman and fluorescence spectroscopy/imagery, confocal laser scanning microscopy, and forms of secondary ion/laser-based mass spectrometry, analytical transmission electron microscopy, and X-ray absorption microscopy/spectroscopy. Analyses can be made for chemical, molecular, and isotopic composition coupled with assessment of spatial relationships to surrounding minerals, veins, and fractures. The bulk analyses include improved methods for minimizing contamination and recognizing syngenetic constituents of soluble organic fractions as well as enhanced spectroscopic and pyrolytic techniques for unlocking syngenetic molecular signatures in kerogen. Together, these technologies provide vital tools for the study of some of the oldest and problematic carbonaceous residues and for advancing our understanding of the earliest stages of biological evolution on Earth and the search for evidence of life beyond Earth. We discuss each of these new technologies, emphasizing their advantages and disadvantages, applications, and likely future directions.

  12. Biogenicity and Syngeneity of Organic Matter in Ancient Sedimentary Rocks: Recent Advances in the Search for Evidence of Past Life

    Science.gov (United States)

    Oehler, Dorothy Z.; Cady, Sherry L.

    2014-08-01

    The past decade has seen an explosion of new technologies for assessment of biogenicity and syngeneity of carbonaceous material within sedimentary rocks. Advances have been made in techniques for analysis of in situ organic matter as well as for extracted bulk samples of soluble and insoluble (kerogen) organic fractions. The in situ techniques allow analysis of micrometer-to-sub-micrometer-scale organic residues within their host rocks and include Raman and fluorescence spectroscopy/imagery, confocal laser scanning microscopy, and forms of secondary ion/laser-based mass spectrometry, analytical transmission electron microscopy, and X-ray absorption microscopy/spectroscopy. Analyses can be made for chemical, molecular, and isotopic composition coupled with assessment of spatial relationships to surrounding minerals, veins, and fractures. The bulk analyses include improved methods for minimizing contamination and recognizing syngenetic constituents of soluble organic fractions as well as enhanced spectroscopic and pyrolytic techniques for unlocking syngenetic molecular signatures in kerogen. Together, these technologies provide vital tools for the study of some of the oldest and problematic carbonaceous residues and for advancing our understanding of the earliest stages of biological evolution on Earth and the search for evidence of life beyond Earth. We discuss each of these new technologies, emphasizing their advantages and disadvantages, applications, and likely future directions.

  13. Biogenicity and Syngeneity of Organic Matter in Ancient Sedimentary Rocks: Recent Advances in the Search for Evidence of Past Life

    Directory of Open Access Journals (Sweden)

    Dorothy Z. Oehler

    2014-08-01

    Full Text Available The past decade has seen an explosion of new technologies for assessment of biogenicity and syngeneity of carbonaceous material within sedimentary rocks. Advances have been made in techniques for analysis of in situ organic matter as well as for extracted bulk samples of soluble and insoluble (kerogen organic fractions. The in situ techniques allow analysis of micrometer-to-sub-micrometer-scale organic residues within their host rocks and include Raman and fluorescence spectroscopy/imagery, confocal laser scanning microscopy, and forms of secondary ion/laser-based mass spectrometry, analytical transmission electron microscopy, and X-ray absorption microscopy/spectroscopy. Analyses can be made for chemical, molecular, and isotopic composition coupled with assessment of spatial relationships to surrounding minerals, veins, and fractures. The bulk analyses include improved methods for minimizing contamination and recognizing syngenetic constituents of soluble organic fractions as well as enhanced spectroscopic and pyrolytic techniques for unlocking syngenetic molecular signatures in kerogen. Together, these technologies provide vital tools for the study of some of the oldest and problematic carbonaceous residues and for advancing our understanding of the earliest stages of biological evolution on Earth and the search for evidence of life beyond Earth. We discuss each of these new technologies, emphasizing their advantages and disadvantages, applications, and likely future directions.

  14. The effects of forage proportion and rapidly degradable dry matter from concentrate on ruminal digestion in dairy cows fed corn silage-based diets with fixed neutral detergent fiber and starch contents.

    Science.gov (United States)

    Lechartier, C; Peyraud, J-L

    2010-02-01

    This study investigated the effects of the forage-to-concentrate (F:C) ratio and the rate of ruminal degradation of carbohydrates from the concentrate on digestion in dairy cows fed corn silage-based diets. Six cows with ruminal cannulas were assigned to 6 treatments in a 6x6 Latin square. Treatments were arranged in a 3x2 factorial design. Three proportions of neutral detergent fiber from forage [FNDF; 7.6, 13.2, and 18.9% of dry matter (DM)] were obtained by modifying F:C (20:80, 35:65, and 50:50). These F:C were combined with concentrates with either high or low content of rapidly degradable carbohydrates. The dietary content of rapidly degradable carbohydrates from the concentrate was estimated from the DM disappearance of concentrate after 4h of in sacco incubation (CRDM). Thus, 2 proportions of CRDM were tested (20 and 30% of DM). Wheat and corn grain were used as rapidly and slowly degradable starch sources, respectively. Soybean hulls and citrus pulp were used as slowly and rapidly degradable fiber sources, respectively. Concentrate composition was adjusted to maintain dietary starch and neutral detergent fiber contents at 35.9 and 28.9% of DM, respectively. There was no effect of the interaction between F:C and CRDM on DM intake (DMI), ruminal fermentation, chewing activity, and fibrolytic activity. When F:C decreased, DMI increased, the mean ruminal pH linearly decreased, and the pH range linearly increased from 0.95 to 1.27 pH unit. At the same time, the acetate-to-propionate ratio decreased linearly. Decreasing F:C linearly decreased the average time spent chewing per kilogram of DMI from 35.2 to 19.5min/kg of DMI and decreased ruminal liquid outflow from 11.6 to 9.2L/kg of DMI, suggesting a decrease in the salivary flow. Increasing CRDM decreased DMI and increased the time during which pH was below 6.0 (3.1 vs. 4.8h), the pH range (0.90 vs. 1.33), and the initial rate of pH drop. It also increased the volatile fatty acid range (35 vs. 59mM), thus

  15. Dark matters

    International Nuclear Information System (INIS)

    Silk, Joseph

    2010-01-01

    One of the greatest mysteries in the cosmos is that it is mostly dark. That is, not only is the night sky dark, but also most of the matter and the energy in the universe is dark. For every atom visible in planets, stars and galaxies today there exists at least five or six times as much 'Dark Matter' in the universe. Astronomers and particle physicists today are seeking to unravel the nature of this mysterious but pervasive dark matter, which has profoundly influenced the formation of structure in the universe. Dark energy remains even more elusive, as we lack candidate fields that emerge from well established physics. I will describe various attempts to measure dark matter by direct and indirect means, and discuss the prospects for progress in unravelling dark energy.

  16. Dirac matter

    CERN Document Server

    Rivasseau, Vincent; Fuchs, Jean-Nöel

    2017-01-01

    This fifteenth volume of the Poincare Seminar Series, Dirac Matter, describes the surprising resurgence, as a low-energy effective theory of conducting electrons in many condensed matter systems, including graphene and topological insulators, of the famous equation originally invented by P.A.M. Dirac for relativistic quantum mechanics. In five highly pedagogical articles, as befits their origin in lectures to a broad scientific audience, this book explains why Dirac matters. Highlights include the detailed "Graphene and Relativistic Quantum Physics", written by the experimental pioneer, Philip Kim, and devoted to graphene, a form of carbon crystallized in a two-dimensional hexagonal lattice, from its discovery in 2004-2005 by the future Nobel prize winners Kostya Novoselov and Andre Geim to the so-called relativistic quantum Hall effect; the review entitled "Dirac Fermions in Condensed Matter and Beyond", written by two prominent theoreticians, Mark Goerbig and Gilles Montambaux, who consider many other mater...

  17. Water-sediment distribution and behaviour of Polonium ("2"1"0Po) in a shallow coastal area with high concentration of dissolved organic matters in water, North Vietnam

    International Nuclear Information System (INIS)

    Tran Thi Van; Nguyen Duc Tam; Dang Duc Nhan; Nguyen Quang Long; Duong Van Thang; Bui Duy Cam

    2016-01-01

    The behaviour and water-sediment distribution of particle-reactive Polonium-210 in the marine environment with high concentration of total suspended particulates (TSP) and dissolved organic matters (DOC) along the coast of the Tonkin Gulf (North Vietnam) were investigated. It was revealed that the water-sediment distribution coefficient, K_d(s), of "2"1"0Po varied from 2.39x10"3 to 1.9x10"4 (L kg"-"1) and from 7x10"3 to 2.5x10"5 (L kg"-"1), respectively, in the rainy and dry season. This implies that in the aquatic environment "2"1"0Po tends to be of high affinity to suspended particulates. The "2"1"0Po K_d(s) was positively correlated with salinity in both rainy and dry seasons. With DOC the K_d(s) was positively correlated in the rainy season, but in the dry season the relationship tended to be reverse. This behaviour of "2"1"0Po in the coastal region was explained by the variation of pH of seawater and by the complexation of the isotope with DOC. The K_d(s) found in this study was in an order lower compared to that reported by Malaysian researchers for the Thailand Gulf. The most important source of "2"1"0Po was suggested to be from in-situ generation by the decay of its grand-parent "2"1"0Pb which mainly derived from the atmospheric fall-out. (author)

  18. Digestibilidade da matéria seca de silagens de milho e de suplementos concentrados determinada por procedimentos in vitro Dry matter digestibility of corn silages and concentrates determined by in vitro procedures

    Directory of Open Access Journals (Sweden)

    F.C.F. Lopes

    2010-10-01

    Full Text Available Compararam-se os valores de digestibilidade in vitro da matéria seca (DIVMS de quatro silagens de milho e de seis concentrados (três proteicos e três energéticos, determinados pelo método de dois estádios realizados em tubos individuais ou em equipamento automatizado de fermentação, e avaliou-se a ocorrência de efeito associativo na digestão de alimentos destas três classes incubadas em um mesmo jarro de fermentação da incubadora in vitro, ou em jarros diferentes contendo a mesma classe de alimentos. Utilizou-se delineamento inteiramente ao acaso, em esquema fatorial 3 x 3 (procedimentos in vitro x classes de alimentos. Os valores de DIVMS determinados pelo método dos tubos foram mais próximos dos relatados na literatura e menores (P0,05 nos valores de DIVMS dos concentrados e das silagens de milho incubados no mesmo jarro de fermentação da incubadora ou, separadamente por alimento, em jarros diferentes.The values of in vitro dry matter digestibility (IVDMD of four corn silages and six concentrates (three proteic and three energetics were determined by the two-stage technique that utilizes individual digestion tubes and by an automatic equipment of fermentation (filter bag technique. It was also evaluated the associative effect on digestion of these three food classes when incubated in the same fermentation jar of the "in vitro incubator" and when in different vessels containing the same class of foods. The experimental design was completely randomized in a 3 x 3 factorial arrangement (in vitro procedures x food classes. The IVDMD values determined in tubes were closer to those found in the literature and lower (P0.05 in IVDMD of concentrates and silages when incubated together in the same fermentation jar or separated by food classes in separated jars.

  19. Quark matter

    Energy Technology Data Exchange (ETDEWEB)

    Csernai, L.; Kampert, K. H.

    1994-10-15

    Precisely one decade ago the GSI (Darmstadt)/LBL (Berkeley) Collaboration at the Berkeley Bevalac reported clear evidence for collective sidewards flow in high energy heavy ion collisions. This milestone observation clearly displayed the compression and heating up of nuclear matter, providing new insights into how the behaviour of nuclear matter changes under very different conditions. This year, evidence for azimuthally asymmetric transverse flow at ten times higher projectile energy (11 GeV per nucleon gold on gold collisions) was presented by the Brookhaven E877 collaboration at the recent European Research Conference on ''Physics of High Energy Heavy Ion Collisions'', held in Helsinki from 17-22 June.

  20. Dark Matter

    Indian Academy of Sciences (India)

    As if this was not enough, it turns out that if our knowledge of ... are thought to contain dark matter, although the evidences from them are the .... protons, electrons, neutrons ... ratio of protons to neutrons was close to unity then as they were in ...

  1. Quantum matter

    International Nuclear Information System (INIS)

    Buechler, Hans Peter; Calcarco, Tommaso; Dressel, Martin

    2008-01-01

    The following topics are dealt with: Artificial atoms and molecules, tailored from solids, fractional flux quanta, molecular magnets, controlled interaction in quantum gases, the theory of quantum correlations in mott matter, cold gases, and mesoscopic systems, Bose-Einstein condensates on the chip, on the route to the quantum computer, a quantum computer in diamond. (HSI)

  2. Molecule Matters

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 4. Molecule Matters – van der Waals Molecules - History and Some Perspectives on Intermolecular Forces. E Arunan. Feature Article Volume 14 Issue 4 April 2009 pp 346-356 ...

  3. Molecule Matters

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 16; Issue 12. Molecule Matters - Dinitrogen. A G Samuelson J Jabadurai. Volume 16 Issue 12 ... Author Affiliations. A G Samuelson1 J Jabadurai1. Department of Inroganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India.

  4. Interstellar matter

    International Nuclear Information System (INIS)

    Mezger, P.G.

    1978-01-01

    An overview of the formation of our galaxy is presented followed by a summary of recent work in star formation and related topics. Selected discussions are given on interstellar matter including absorption characteristics of dust, the fully ionised component of the ISM and the energy density of lyc-photons in the solar neighbourhood and the diffuse galactic IR radiation

  5. Dark Matter

    Indian Academy of Sciences (India)

    The study of gas clouds orbiting in the outer regions of spiral galaxies has revealed that their gravitational at- traction is much larger than the stars alone can provide. Over the last twenty years, astronomers have been forced to postulate the presence of large quantities of 'dark matter' to explain their observations. They are ...

  6. Molecule Matters

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 9. Molecule Matters - A Chromium Compound with a Quintuple Bond. K C Kumara Swamy. Feature Article Volume 11 Issue 9 September 2006 pp 72-75. Fulltext. Click here to view fulltext PDF. Permanent link:

  7. Dark Matter

    International Nuclear Information System (INIS)

    Audouze, J.; Tran Thanh Van, J.

    1988-01-01

    The book begins with the papers devoted to the experimental search of signatures of the dark matter which governs the evolution of the Universe as a whole. A series of contributions describe the presently considered experimental techniques (cryogenic detectors, supraconducting detectors...). A real dialogue concerning these techniques has been instaured between particle physicists and astrophysicists. After the progress report of the particle physicists, the book provides the reader with an updated situation concerning the research in cosmology. The second part of the book is devoted to the analysis of the backgrounds at different energies such as the possible role of the cooling flows in the constitution of massive galactic halos. Any search of dark matter implies necessarily the analysis of the spatial distributions of the large scale structures of the Universe. This report is followed by a series of statistical analyses of these distributions. These analyses concern mainly universes filled up with cold dark matter. The last paper of this third part concerns the search of clustering in the spatial distribution of QSOs. The presence of dark matter should affect the solar neighborhood and related to the existence of galactic haloes. The contributions are devoted to the search of such local dark matter. Primordial nucleosynthesis provides a very powerful tool to set up quite constraining limitations on the overall baryonic density. Even if on takes into account the inhomogeneities in density possibly induced by the Quark-Hadron transition, this baryonic density should be much lower than the overall density deduced from the dynamical models of Universe or the inflationary theories

  8. Disposal Of Waste Matter

    International Nuclear Information System (INIS)

    Kim, Jeong Hyeon; Lee, Seung Mu

    1989-02-01

    This book deals with disposal of waste matter management of soiled waste matter in city with introduction, definition of waste matter, meaning of management of waste matter, management system of waste matter, current condition in the country, collect and transportation of waste matter disposal liquid waste matter, industrial waste matter like plastic, waste gas sludge, pulp and sulfuric acid, recycling technology of waste matter such as recycling system of Black clawson, Monroe and Rome.

  9. Quark matter

    International Nuclear Information System (INIS)

    Csernai, L.; Kampert, K.H.

    1994-01-01

    Precisely one decade ago the GSI (Darmstadt)/LBL (Berkeley) Collaboration at the Berkeley Bevalac reported clear evidence for collective sidewards flow in high energy heavy ion collisions. This milestone observation clearly displayed the compression and heating up of nuclear matter, providing new insights into how the behaviour of nuclear matter changes under very different conditions. This year, evidence for azimuthally asymmetric transverse flow at ten times higher projectile energy (11 GeV per nucleon gold on gold collisions) was presented by the Brookhaven E877 collaboration at the recent European Research Conference on ''Physics of High Energy Heavy Ion Collisions'', held in Helsinki from 17-22 June

  10. Heterogeneity of the organic matter in the Guayuta group, Eastern Venezuelan Basin

    Energy Technology Data Exchange (ETDEWEB)

    Alberdi, M.; Gallango, O.; Ruggiero, A.; Jordan, N. (Intevep, S.A., Caracas (Venezuela)); Lefargue, E. (I.F.P., Rueil Malmaison (France))

    1993-02-01

    The purpose of this study is to evaluate the organic matter heterogeneities in the Guayuta Group as a principal hydrocarbon source rock in the Eastern Venezuelan Basin. In order to do this, thirteen wells and five work stations on outcrops of the Interior Mountain Belt were analyzed to study the regional and vertical variations in the geochemical characteristics of the organic matter. It is possible to detect significant differences in quality and quantity of the organic matter which could corroborate the regional development of two organic facies from North to South in the Maturin Subbasin. The northern organic facies show excellent characteristics as source rock. The study of vertical distribution of organic matter was carried out in a well of northern part of the Monagas state, which represents the southern organic facies. It shows an irregular input of continental organic matter, thermally immature. Besides the organic matter content was low (around 1.5%) without depth tendencies. These sediments are clastic and bioclastic in contrast with carbonates and pelagic shales of the Guayuta Group in the Interior Mountain Belt. The outcrop samples studied show a high total organic content (2-6%) despite the high maturity determined on kerogen. The systematic study of this geochemical parameter show pseudocyclic relationships with a general tendency to increase toward the bottom of the section. V, Ni, and S determinations could indicate that anoxic conditions were developing toward the North where the marine organic matter was sedimenting. The results of this study are in agreement with paleogeographic model of sedimentation during middle and late Cretaceous, with sources of sediments from South and a progressive depth of the basin toward the North.

  11. Media Matter

    Directory of Open Access Journals (Sweden)

    Holger Pötzsch

    2017-02-01

    Full Text Available The present contribution maps materialist advances in media studies. Based on the assumption that matter and materiality constitute significant aspects of communication processes and practices, I introduce four fields of inquiry - technology, political economy, ecology, and the body - and argue that these perspectives enable a more comprehensive understanding of the implications of contemporary technologically afforded forms of interaction. The article shows how each perspective can balance apologetic and apocalyptic approaches to the impact of in particular digital technologies, before it demonstrates the applicability of an integrated framework with reference to the techno-politics of NSA surveillance and the counter-practices of WikiLeaks.

  12. Play Matters

    DEFF Research Database (Denmark)

    Sicart (Vila), Miguel Angel

    ? In Play Matters, Miguel Sicart argues that to play is to be in the world; playing is a form of understanding what surrounds us and a way of engaging with others. Play goes beyond games; it is a mode of being human. We play games, but we also play with toys, on playgrounds, with technologies and design......, but not necessarily fun. Play can be dangerous, addictive, and destructive. Along the way, Sicart considers playfulness, the capacity to use play outside the context of play; toys, the materialization of play--instruments but also play pals; playgrounds, play spaces that enable all kinds of play; beauty...

  13. Effect of organic matter properties, clay mineral type and thermal maturity on gas adsorption in organic-rich shale systems

    Science.gov (United States)

    Zhang, Tongwei; Ellis, Geoffrey S.; Ruppel, Stephen C.; Milliken, Kitty; Lewan, Mike; Sun, Xun; Baez, Luis; Beeney, Ken; Sonnenberg, Steve

    2013-01-01

    A series of CH4 adsorption experiments on natural organic-rich shales, isolated kerogen, clay-rich rocks, and artificially matured Woodford Shale samples were conducted under dry conditions. Our results indicate that physisorption is a dominant process for CH4 sorption, both on organic-rich shales and clay minerals. The Brunauer–Emmett–Teller (BET) surface area of the investigated samples is linearly correlated with the CH4 sorption capacity in both organic-rich shales and clay-rich rocks. The presence of organic matter is a primary control on gas adsorption in shale-gas systems, and the gas-sorption capacity is determined by total organic carbon (TOC) content, organic-matter type, and thermal maturity. A large number of nanopores, in the 2–50 nm size range, were created during organic-matter thermal decomposition, and they significantly contributed to the surface area. Consequently, methane-sorption capacity increases with increasing thermal maturity due to the presence of nanopores produced during organic-matter decomposition. Furthermore, CH4 sorption on clay minerals is mainly controlled by the type of clay mineral present. In terms of relative CH4 sorption capacity: montmorillonite ≫ illite – smectite mixed layer > kaolinite > chlorite > illite. The effect of rock properties (organic matter content, type, maturity, and clay minerals) on CH4 adsorption can be quantified with the heat of adsorption and the standard entropy, which are determined from adsorption isotherms at different temperatures. For clay-mineral rich rocks, the heat of adsorption (q) ranges from 9.4 to 16.6 kJ/mol. These values are considerably smaller than those for CH4 adsorption on kerogen (21.9–28 kJ/mol) and organic-rich shales (15.1–18.4 kJ/mol). The standard entropy (Δs°) ranges from -64.8 to -79.5 J/mol/K for clay minerals, -68.1 to -111.3 J/mol/K for kerogen, and -76.0 to -84.6 J/mol/K for organic-rich shales. The affinity of CH4 molecules for sorption on organic matter

  14. Organic matter in central California radiation fogs.

    Science.gov (United States)

    Herckes, Pierre; Lee, Taehyoung; Trenary, Laurie; Kang, Gongunn; Chang, Hui; Collett, Jeffrey L

    2002-11-15

    Organic matter was studied in radiation fogs in the San Joaquin Valley of California during the California Regional Particulate Air Quality Study (CRPAQS). Total organic carbon (TOC) concentrations ranged from 2 to 40 ppm of C. While most organic carbon was found in solution as dissolved organic carbon (DOC), 23% on average was not dissolved inside the fog drops. We observe a clear variation of organic matter concentration with droplet size. TOC concentrations in small fog drops (fogwater, consistent with the enrichment of the organic matter in smaller fog drops with lower terminal settling velocities.

  15. Standardization of reflectance measurements in dispersed organic matter: results of an exercise to improve interlaboratory agreement

    Science.gov (United States)

    Hackley, Paul C.; Araujo, Carla Viviane; Borrego, Angeles G.; Bouzinos, Antonis; Cardott, Brian; Cook, Alan C.; Eble, Cortland; Flores, Deolinda; Gentzis, Thomas; Gonçalves, Paula Alexandra; Filho, João Graciano Mendonça; Hámor-Vidó, Mária; Jelonek, Iwona; Kommeren, Kees; Knowles, Wayne; Kus, Jolanta; Mastalerz, Maria; Menezes, Taíssa Rêgo; Newman, Jane; Pawlewicz, Mark; Pickel, Walter; Potter, Judith; Ranasinghe, Paddy; Read, Harold; Reyes, Julito; Rodriguez, Genaro De La Rosa; de Souza, Igor Viegas Alves Fernandes; Suarez-Ruiz, Isabel; Sýkorová, Ivana; Valentine, Brett J.

    2015-01-01

    the other components. Discussion among participants suggested this problem could not be easily corrected via kerogen concentration or solvent extraction and is related to operator training and background. No statistical difference in mean reflectance was identified between participants reporting bitumen reflectance vs. vitrinite reflectance vs. a mixture of bitumen and vitrinite reflectance values, suggesting empirical conversion schemes should be treated with caution. Analysis of reproducibility limits obtained during this exercise in comparison to reproducibility limits from historical interlaboratory exercises suggests use of a common methodology (D7708) improves interlaboratory precision. Future work will investigate opportunities to improve reproducibility in high maturity, organic-lean shale varieties.

  16. Concentrated Ownership

    DEFF Research Database (Denmark)

    Rose, Caspar

    2014-01-01

    This entry summarizes the main theoretical contributions and empirical findings in relation to concentrated ownership from a law and economics perspective. The various forms of concentrated ownership are described as well as analyzed from the perspective of the legal protection of investors......, especially minority shareholders. Concentrated ownership is associated with benefits and costs. Concentrated ownership may reduce agency costs by increased monitoring of top management. However, concentrated ownership may also provide dominating owners with private benefits of control....

  17. Marginal Matter

    Science.gov (United States)

    van Hecke, Martin

    2013-03-01

    All around us, things are falling apart. The foam on our cappuccinos appears solid, but gentle stirring irreversibly changes its shape. Skin, a biological fiber network, is firm when you pinch it, but soft under light touch. Sand mimics a solid when we walk on the beach but a liquid when we pour it out of our shoes. Crucially, a marginal point separates the rigid or jammed state from the mechanical vacuum (freely flowing) state - at their marginal points, soft materials are neither solid nor liquid. Here I will show how the marginal point gives birth to a third sector of soft matter physics: intrinsically nonlinear mechanics. I will illustrate this with shock waves in weakly compressed granular media, the nonlinear rheology of foams, and the nonlinear mechanics of weakly connected elastic networks.

  18. Elliptical concentrators.

    Science.gov (United States)

    Garcia-Botella, Angel; Fernandez-Balbuena, Antonio Alvarez; Bernabeu, Eusebio

    2006-10-10

    Nonimaging optics is a field devoted to the design of optical components for applications such as solar concentration or illumination. In this field, many different techniques have been used to produce optical devices, including the use of reflective and refractive components or inverse engineering techniques. However, many of these optical components are based on translational symmetries, rotational symmetries, or free-form surfaces. We study a new family of nonimaging concentrators called elliptical concentrators. This new family of concentrators provides new capabilities and can have different configurations, either homofocal or nonhomofocal. Translational and rotational concentrators can be considered as particular cases of elliptical concentrators.

  19. Hyperons in dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Dapo, Haris

    2009-01-28

    The hyperon-nucleon YN low momentum effective interaction (V{sub low} {sub k}) allows for an extensive study of the behavior of hyperons in dense matter, together with an investigation of effects of the presence of hyperons on dense matter. The first step towards this goal is the construction of the matrix elements for the hyperon-nucleon low momentum potential. In order to assess the different properties of hyperons within these potentials we calculate the hyperon single-particle potentials in the Hartree-Fock approximation for all of the interactions. Their dependence on both momentum and density, is studied. The single-particle potentials are then used to determine the chemical potential of hyperons in neutron stars. For nucleonic properties, the nucleon-nucleon V{sub low} {sub k} can be used with the caveat that the calculation of the ground-state energy of symmetric nuclear matter does not correctly reproduce the properties of matter at saturation. With the nucleon-nucleon V{sub low} {sub k} one is unable to reach the densities needed for the calculation of neutron star masses. To circumvent this problem we use two approaches: in the first one, we parametrize the entire nucleonic sector. In the second one, we replace only the three-body force. The former will enable us to study neutron star masses, and the latter for studying the medium's response to the external probe. In this thesis we take the external probe to be the neutrino. By combining this parametrization with the YN V{sub low} {sub k} potential, we calculate the equation of state of equilibrated matter. Performing the calculation in the Hartree-Fock approximation at zero temperature, the concentrations of all particles are calculated. From these we can ascertain at which densities hyperons appear for a wide range of parameters. Finally, we calculate the masses of neutron stars with these concentrations. For the calculation of the medium's response to an external probe, we replace the three

  20. Hyperons in dense matter

    International Nuclear Information System (INIS)

    Dapo, Haris

    2009-01-01

    The hyperon-nucleon YN low momentum effective interaction (V low k ) allows for an extensive study of the behavior of hyperons in dense matter, together with an investigation of effects of the presence of hyperons on dense matter. The first step towards this goal is the construction of the matrix elements for the hyperon-nucleon low momentum potential. In order to assess the different properties of hyperons within these potentials we calculate the hyperon single-particle potentials in the Hartree-Fock approximation for all of the interactions. Their dependence on both momentum and density, is studied. The single-particle potentials are then used to determine the chemical potential of hyperons in neutron stars. For nucleonic properties, the nucleon-nucleon V low k can be used with the caveat that the calculation of the ground-state energy of symmetric nuclear matter does not correctly reproduce the properties of matter at saturation. With the nucleon-nucleon V low k one is unable to reach the densities needed for the calculation of neutron star masses. To circumvent this problem we use two approaches: in the first one, we parametrize the entire nucleonic sector. In the second one, we replace only the three-body force. The former will enable us to study neutron star masses, and the latter for studying the medium's response to the external probe. In this thesis we take the external probe to be the neutrino. By combining this parametrization with the YN V low k potential, we calculate the equation of state of equilibrated matter. Performing the calculation in the Hartree-Fock approximation at zero temperature, the concentrations of all particles are calculated. From these we can ascertain at which densities hyperons appear for a wide range of parameters. Finally, we calculate the masses of neutron stars with these concentrations. For the calculation of the medium's response to an external probe, we replace the three-body force with a density-dependent interaction. This

  1. Hydrocarbons and oxygen compounds in the bitumens of kukersite oil shales

    Energy Technology Data Exchange (ETDEWEB)

    Pais, R; Klesment, I; Pobul, L

    1979-01-01

    This is a continuation of an earlier work which described commercial batches of kukersite in terms of oxidative kerogen destruction. The low concentration of bitumen in the kerogen and its group composition indicate that this bitumen is syngenetic. The authors studied the way in which the bitumen and kerogen are structurally connected. They also analyzed four commercial batches of kukersite and asphaltite, the organic-rich dark-colored layer found in the middle of the kukersite strate. Whereas American studies of Colorado shales containing 10-20% bitumen from organic matter have indicated, based on the identical structures of the bitumen and kerogen that there is a genetic relationship between them, the present study rarely found such structural elements in the bitumen and kerogen. The kukersite contained little bitumen--0.7% of the total organic matter. The authors believed that the different composition of the bitumen and kerogen does not prove that they are epigenetic. Kukersite also fails to follow the rule that the paraffins of ancient shales have KHapprox.1 and carbon chains shorter than C/sub 22/.

  2. Concentration risk

    Directory of Open Access Journals (Sweden)

    Matić Vesna

    2016-01-01

    Full Text Available Concentration risk has been gaining a special dimension in the contemporary financial and economic environment. Financial institutions are exposed to this risk mainly in the field of lending, mostly through their credit activities and concentration of credit portfolios. This refers to the concentration of different exposures within a single risk category (credit risk, market risk, operational risk, liquidity risk.

  3. Allegheny County Particulate Matter 2.5

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The U.S. Environmental Protection Agency provides information on the particulate matter concentration for Allegheny County that have a diameter greater or equal to...

  4. Concentrator Photovoltaics

    CERN Document Server

    Luque, Antonio L

    2007-01-01

    Photovoltaic solar-energy conversion is one of the most promising technologies for generating renewable energy, and conversion of concentrated sunlight can lead to reduced cost for solar electricity. In fact, photovoltaic conversion of concentrated sunlight insures an efficient and cost-effective sustainable power resource. This book gives an overview of all components, e.g. cells, concentrators, modules and systems, for systems of concentrator photovoltaics. The authors report on significant results related to design, technology, and applications, and also cover the fundamental physics and market considerations. Specific contributions include: theory and practice of sunlight concentrators; an overview of concentrator PV activities; a description of concentrator solar cells; design and technology of modules and systems; manufacturing aspects; and a market study.

  5. Baryonic matter and beyond

    OpenAIRE

    Fukushima, Kenji

    2014-01-01

    We summarize recent developments in identifying the ground state of dense baryonic matter and beyond. The topics include deconfinement from baryonic matter to quark matter, a diquark mixture, topological effect coupled with chirality and density, and inhomogeneous chiral condensates.

  6. Front Matter

    Directory of Open Access Journals (Sweden)

    HLRC Editor

    2016-08-01

    Full Text Available Higher Learning Research Communications (HLRC, ISSN: 2157-6254 [Online] is published collaboratively by Walden University (USA, Universidad Andrés Bello (Chile, Universidad Europea de Madrid (Spain and Istanbul Bilgi University (Turkey. Written communication to HLRC should be addressed to the office of the Executive Director at Laureate Education, Inc. 701 Brickell Ave Ste. 1700, Miami, FL 33131, USA. HLRC is designed for open access and online distribution through www.hlrcjournal.com. The views and statements expressed in this journal do not necessarily reflect the views of Laureate Education, Inc. or any of its affiliates (collectively “Laureate”. Laureate does not warrant the accuracy, reliability, currency or completeness of those views or statements and does not accept any legal liability arising from any reliance on the views, statements and subject matter of the journal. Acknowledgements The Guest Editors gratefully acknowledge the substantial contribution of the readers for the blind peer review of essays submitted for this special issue as exemplars of individuals from around the world who have come together in a collective endeavor for the common good: Robert Bringle (Indiana University Purdue University Indianapolis, US, Linda Buckley (University of the Pacific, US, Guillermo Calleja (Universidad Rey Juan Carlos, Spain, Eva Egron-Polak (International Association of Universities, France, Heather Friesen (Abu Dhabi University, UAE, Saran Gill (National University of Malaysia, Malaysia, Chester Haskell (higher education consultant, US, Kanokkarn Kaewnuch (National Institute for Development Administration, Thailand, Gil Latz (Indiana University Purdue University Indianapolis, US, Molly Lee (higher education consultant, Malaysia, Deane Neubauer (East-West Center at University of Hawaii, US, Susan Sutton (Bryn Mawr College, US, Francis Wambalaba (United States International University, Kenya, and Richard Winn (higher education

  7. Urban tree effects on fine particulate matter and human health

    Science.gov (United States)

    David J. Nowak

    2014-01-01

    Overall, city trees reduce particulate matter and provide substantial health benefits; but under certain conditions, they can locally increase particulate matter concentrations. Urban foresters need to understand how trees affect particulate matter so they can select proper species and create appropriate designs to improve air quality. This article details trees'...

  8. Passage kinetics of dry matter and neutral detergent fibre through the gastro-intestinal tract of growing beef heifers fed a high-concentrate diet measured with internal ð13C and external markers

    NARCIS (Netherlands)

    Daniel, J.B.; Laar, van H.; Warner, D.; Dijkstra, J.; Navarro-Villa, A.; Pellikaan, W.F.

    2014-01-01

    Fractional rumen passage rates (K1) are fundamental in feed evaluation systems for ruminants to predict the extent of nutrient degradation. Data on passage kinetics of growing beef cattle fed high-concentrate diets are scarce and mainly rely on external passage markers which do not provide

  9. Diversity and Distribution of Heavy Metal-Resistant Bacteria in Polluted Sediments of the Araça Bay, São Sebastião (SP), and the Relationship Between Heavy Metals and Organic Matter Concentrations.

    Science.gov (United States)

    Zampieri, Bruna Del Busso; Pinto, Aline Bartelochi; Schultz, Leonardo; de Oliveira, Marcos Antonio; de Oliveira, Ana Julia Fernandes Cardoso

    2016-10-01

    Heavy metals influence the population size, diversity, and metabolic activity of bacteria. In turn, bacteria can develop heavy metal resistance mechanisms, and this can be used in bioremediation of contaminated areas. The purpose of the present study was to understand how heavy metals concentration influence on diversity and distribution of heavy metal-resistant bacteria in Araça Bay, São Sebastião, on the São Paulo coast of Brazil. The hypothesis is that activities that contribute for heavy metal disposal and the increase of metals concentrations in environment can influence in density, diversity, and distribution of heavy metal-resistant bacteria. Only 12 % of the isolated bacteria were sensitive to all of the metals tested. We observed that the highest percentage of resistant strains were in areas closest to the São Sebastião channel, where port activity occurs and have bigger heavy metals concentrations. Bacterial isolated were most resistant to Cr, followed by Zn, Cd, and Cu. Few strains resisted to Cd levels greater than 200 mg L(-1). In respect to Cr, 36 % of the strains were able to grow in the presence of as much as 3200 mg L(-1). Few strains were able to grow at concentrations of Zn and Cu as high as 1600 mg L(-1), and none grew at the highest concentration of 3200 mg L(-1). Bacillus sp. was most frequently isolated and may be the dominant genus in heavy metal-polluted areas. Staphylococcus sp., Planococcus maritimus, and Vibrio aginolyticus were also isolated, suggesting their potential in bioremediation of contaminated sites.

  10. Conducting compositions of matter

    Science.gov (United States)

    Viswanathan, Tito (Inventor)

    2000-01-01

    The invention provides conductive compositions of matter, as well as methods for the preparation of the conductive compositions of matter, solutions comprising the conductive compositions of matter, and methods of preparing fibers or fabrics having improved anti-static properties employing the conductive compositions of matter.

  11. Simulation thermique de l'évolution diagénétique des kérogènes : étude par résonance paramagnétique électronique Thermal Simulation of the Diagenetic Evolution of Kerogens: Electron Paramagnetic Resonance Analysis

    Directory of Open Access Journals (Sweden)

    Villey M.

    2006-11-01

    Full Text Available Dans cet article sont exposés les résultats obtenus en résonance paramagnétique électronique (RPE sur des séries chauffées en laboratoire, d'échantillons de kérogènes, illustrant les trois lignées évolutives. L'évolution de ces kérgènes est caractérisée par la susceptibilité paramagnétique, la largeur et la forme de la raie RPE et le facteur de décomposition spectrale g. Ces résultats sont, d'une part comparés à ceux obtenus (sur les mêmes échantillons en microscopie électronique à haute résolution, en spectroscopie infra-rouge, en analyse thermique et élémentaire, d'autre part confrontés aux données RPE de kérogènes différents précédemment étudiés. Enfin, le modèle d'évolution d'un carbonisat proposé par la microscopie électronique est ici complété. This article describes the results obtained by electron paramagnetic resonance (EPR analysis of heated series of kerogen samples in the laboratory to illustrate three evolutive lines. The evolution of these kerogens is characterized by paramagnet susceptibility, the width and shape of the EPR line and the spectral decomposition factor g. These results are compared with those obtained (with the same samples by high-resolution electron microscopy, infrared spectroscopy and thermal and elemental analysis. They are also compared with EPR data from previous kerogen analyses. The evolution model of a carbonizate proposed by electron microscopy is completed here.

  12. Method of enriching oil shale concentrate

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, M

    1942-02-14

    The method is characterized by producing one concentrate first and then this concentrate, in water solution using suitable apparatus, is separated by settling into one heavier bottom portion, rich in mineral matter, and into a lighter slime containing concentrated organic substance.

  13. Comparison of Metabolite Concentrations in the Left Dorsolateral Prefrontal Cortex, the Left Frontal White Matter, and the Left Hippocampus in Patients in Stable Schizophrenia Treated with Antipsychotics with or without Antidepressants. 1H-NMR Spectroscopy Study

    Directory of Open Access Journals (Sweden)

    Dominik Strzelecki

    2015-10-01

    Full Text Available Managing affective, negative, and cognitive symptoms remains the most difficult therapeutic problem in stable phase of schizophrenia. Efforts include administration of antidepressants. Drugs effects on brain metabolic parameters can be evaluated by means of proton nuclear magnetic resonance (1H-NMR spectroscopy. We compared spectroscopic parameters in the left prefrontal cortex (DLPFC, the left frontal white matter (WM and the left hippocampus and assessed the relationship between treatment and the spectroscopic parameters in both groups. We recruited 25 patients diagnosed with schizophrenia (DSM-IV-TR, with dominant negative symptoms and in stable clinical condition, who were treated with antipsychotic and antidepressive medication for minimum of three months. A group of 25 patients with schizophrenia, who were taking antipsychotic drugs but not antidepressants, was matched. We compared metabolic parameters (N-acetylaspartate (NAA, myo-inositol (mI, glutamatergic parameters (Glx, choline (Cho, and creatine (Cr between the two groups. All patients were also assessed with the Positive and Negative Syndrome Scale (PANSS and the Calgary Depression Scale for Schizophrenia (CDSS. In patients receiving antidepressants we observed significantly higher NAA/Cr and NAA/Cho ratios within the DLPFC, as well as significantly higher mI/Cr within the frontal WM. Moreover, we noted significantly lower values of parameters associated with the glutamatergic transmission—Glx/Cr and Glx/Cho in the hippocampus. Doses of antipsychotic drugs in the group treated with antidepressants were also significantly lower in the patients showing similar severity of psychopathology.

  14. Condensed elementary particle matter

    International Nuclear Information System (INIS)

    Kajantie, K.

    1996-01-01

    Quark matter is a special case of condensed elementary particle matter, matter governed by the laws of particle physics. The talk discusses how far one can get in the study of particle matter by reducing the problem to computations based on the action. As an example the computation of the phase diagram of electroweak matter is presented. It is quite possible that ultimately an antireductionist attitude will prevail: experiments will reveal unpredicted phenomena not obviously reducible to the study of the action. (orig.)

  15. Short term variations in particulate matter in Mahi river estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Rokade, M.A.; Zingde, M.D.

    The particulate matter (PM) collected from Mahi River Estuary was analysed for organic carbon (POC), nitrogen (PON), and chlorophyll a (Chl a). The concentration of PM, POC, PON and Chl a showed short term variations. Average surface concentration...

  16. Concentrating Radioactivity

    Science.gov (United States)

    Herrmann, Richard A.

    1974-01-01

    By concentrating radioactivity contained on luminous dials, a teacher can make a high reading source for classroom experiments on radiation. The preparation of the source and its uses are described. (DT)

  17. Inverted dipole feature in directional detection of exothermic dark matter

    International Nuclear Information System (INIS)

    Bozorgnia, Nassim; Gelmini, Graciela B.; Gondolo, Paolo

    2017-01-01

    Directional dark matter detection attempts to measure the direction of motion of nuclei recoiling after having interacted with dark matter particles in the halo of our Galaxy. Due to Earth's motion with respect to the Galaxy, the dark matter flux is concentrated around a preferential direction. An anisotropy in the recoil direction rate is expected as an unmistakable signature of dark matter. The average nuclear recoil direction is expected to coincide with the average direction of dark matter particles arriving to Earth. Here we point out that for a particular type of dark matter, inelastic exothermic dark matter, the mean recoil direction as well as a secondary feature, a ring of maximum recoil rate around the mean recoil direction, could instead be opposite to the average dark matter arrival direction. Thus, the detection of an average nuclear recoil direction opposite to the usually expected direction would constitute a spectacular experimental confirmation of this type of dark matter.

  18. Soil organic matter studies

    International Nuclear Information System (INIS)

    1977-01-01

    A total of 77 papers were presented and discussed during this symposium, 37 are included in this Volume II. The topics covered in this volume include: biochemical transformation of organic matter in soils; bitumens in soil organic matter; characterization of humic acids; carbon dating of organic matter in soils; use of modern techniques in soil organic matter research; use of municipal sludge with special reference to heavy metals constituents, soil nitrogen, and physical and chemical properties of soils; relationship of soil organic matter and plant metabolism; interaction between agrochemicals and organic matter; and peat. Separate entries have been prepared for those 20 papers which discuss the use of nuclear techniques in these studies

  19. AN In vitro ASSESSMENT OF SUPPLEMENTARY EFFECT OF CONCENTRATES CONTAINING GRADED LEVELS OF GROUND LINSEED (Linum usitatissimum TO HOUSEHOLD WASTES ON ORGANIC MATTER DEGRADABILITY, SHORT CHAIN FATTY ACIDS, MICROBIAL PROTEIN, METABOLIZABLE ENERGY AND RELATIVE FEED VALUES

    Directory of Open Access Journals (Sweden)

    Tegene Negesse

    2016-08-01

    Full Text Available With the objective to assess effect of level of linseed inclusion in feeds on nutritive value, an in vitro OM digestibility (IVOMD, total short chain fatty acids (SCFA:mMol l-1, microbial crude protein (MCP:g kg-1 DM, metabolizable energy (MEruminants:MJ kg-1 DM and relative feed values (RFV of household wastes=HW (Areke-Atela=AA, carrot peels=CaP, cabbage leaf=Cle, cabbage leftover=Clef, onion leaf=OL, onion peels=OP, potato peels=PP, Tela-Atela=TA supplemented with linseed (LS containing concentrates=LSC1…LSC5 (39.32, 37.32, 35.32, 33.32, 31.32% noug cake + 58.99% wheat bran + 1.69% salt + 0, 2, 4, 6, 8% LS, as fed basis were estimated via an in vitro gas trial. HWs were mixed with LSC (LSC-HW at 3:1 ratio. Samples were incubated in-vitro with rumen fluid in duplicate and readings recorded at 0, 3, 6, 12, 24, 48, 72 and 96 h of incubation. LSC-HW mixtures had higher CP, IVDMD, IVOMD, ME and SCFA, MCP and RFV than those of HWs alone. IVDMD and IVOMD of the LSC-HW improved with increasing LS levels, mostly at 2 and 4%LSC; but at higher concentrations they declined.  AA, TA had high IVOMD. However, IVDMD of AA (with the lowest IVDMD was much more influenced than TA (with highest IVDMD by LS levels. Clef had lowest and AA and TA highest ME. SCFA increased over incubation periods and with increasing levels of LS, in Clef improvement (from 0.25 to 0.61 mMol l-1 was significant but in AA (from 0.69 to 0.72 mMol l-1 moderate. Mixing HWs with LSC gave best results at 2%LSC.

  20. Global Particulate Matter Source Apportionment

    Science.gov (United States)

    Lamancusa, C.; Wagstrom, K.

    2017-12-01

    As our global society develops and grows it is necessary to better understand the impacts and nuances of atmospheric chemistry, in particular those associated with atmospheric particulate matter. We have developed a source apportionment scheme for the GEOS-Chem global atmospheric chemical transport model. While these approaches have existed for several years in regional chemical transport models, the Global Particulate Matter Source Apportionment Technology (GPSAT) represents the first incorporation into a global chemical transport model. GPSAT runs in parallel to a standard GEOS-Chem run. GPSAT uses the fact that all molecules of a given species have the same probability of undergoing any given process as a core principle. This allows GPSAT to track many different species using only the flux information provided by GEOS-Chem's many processes. GPSAT accounts for the change in source specific concentrations as a result of aqueous and gas-phase chemistry, horizontal and vertical transport, condensation and evaporation on particulate matter, emissions, and wet and dry deposition. By using fluxes, GPSAT minimizes computational cost by circumventing the computationally costly chemistry and transport solvers. GPSAT will allow researchers to address many pertinent research questions about global particulate matter including the global impact of emissions from different source regions and the climate impacts from different source types and regions. For this first application of GPSAT, we investigate the contribution of the twenty largest urban areas worldwide to global particulate matter concentrations. The species investigated include: ammonium, nitrates, sulfates, and the secondary organic aerosols formed by the oxidation of benzene, isoprene, and terpenes. While GPSAT is not yet publically available, we will incorporate it into a future standard release of GEOS-Chem so that all GEOS-Chem users will have access to this new tool.

  1. Baryonic Dark Matter

    OpenAIRE

    Silk, Joseph

    1994-01-01

    In the first two of these lectures, I present the evidence for baryonic dark matter and describe possible forms that it may take. The final lecture discusses formation of baryonic dark matter, and sets the cosmological context.

  2. Grammar of the matter

    International Nuclear Information System (INIS)

    Jacob, M.

    1992-01-01

    In this paper, the author describes the structure of the matter and presents the families of elementary particles (fermions) and the interaction messengers (bosons) with their properties. He presents the actual status and future trends of research on nuclear matter

  3. Dark matter detectors

    International Nuclear Information System (INIS)

    Forster, G.

    1995-01-01

    A fundamental question of astrophysics and cosmology is the nature of dark matter. Astrophysical observations show clearly the existence of some kind of dark matter, though they cannot yet reveal its nature. Dark matter can consist of baryonic particles, or of other (known or unknown) elementary particles. Baryonic dark matter probably exists in the form of dust, gas, or small stars. Other elementary particles constituting the dark matter can possibly be measured in terrestrial experiments. Possibilities for dark matter particles are neutrinos, axions and weakly interacting massive particles (WIMPs). While a direct detection of relic neutrinos seems at the moment impossible, there are experiments looking for baryonic dark matter in the form of Massive Compact Halo Objects, and for particle dark matter in the form of axions and WIMPS. (orig.)

  4. Dence Cold Matter

    Directory of Open Access Journals (Sweden)

    Stavinskiy Alexey

    2014-04-01

    Full Text Available Possible way to create dense cold baryonic matter in the laboratory is discussed. The density of this matter is comparable or even larger than the density of neutron star core. The properties of this matter can be controlled by trigger conditions. Experimental program for the study of properties of dense cold matter for light and heavy ion collisions at initial energy range √sNN~2-3GeV is proposed..

  5. Dark Matter Effective Theory

    DEFF Research Database (Denmark)

    Del Nobile, Eugenio; Sannino, Francesco

    2012-01-01

    We organize the effective (self)interaction terms for complex scalar dark matter candidates which are either an isosinglet, isodoublet or an isotriplet with respect to the weak interactions. The classification has been performed ordering the operators in inverse powers of the dark matter cutoff...... scale. We assume Lorentz invariance, color and charge neutrality. We also introduce potentially interesting dark matter induced flavor-changing operators. Our general framework allows for model independent investigations of dark matter properties....

  6. Nonthermal Supermassive Dark Matter

    Science.gov (United States)

    Chung, Daniel J. H.; Kolb, Edward W.; Riotto, Antonio

    1999-01-01

    We discuss several cosmological production mechanisms for nonthermal supermassive dark matter and argue that dark matter may he elementary particles of mass much greater than the weak scale. Searches for dark matter should ma be limited to weakly interacting particles with mass of the order of the weak scale, but should extend into the supermassive range as well.

  7. Nonthermal Supermassive Dark Matter

    International Nuclear Information System (INIS)

    Chung, D.J.; Chung, D.J.; Kolb, E.W.; Kolb, E.W.; Riotto, A.

    1998-01-01

    We discuss several cosmological production mechanisms for nonthermal supermassive dark matter and argue that dark matter may be elementary particles of mass much greater than the weak scale. Searches for dark matter should not be limited to weakly interacting particles with mass of the order of the weak scale, but should extend into the supermassive range as well. copyright 1998 The American Physical Society

  8. Nonthermal Supermassive Dark Matter

    OpenAIRE

    Chung, Daniel J. H.; Kolb, Edward W.; Riotto, Antonio

    1998-01-01

    We discuss several cosmological production mechanisms for nonthermal supermassive dark matter and argue that dark matter may be elementary particles of mass much greater than the weak scale. Searches for dark matter should not be limited to weakly interacting particles with mass of the order of the weak scale, but should extend into the supermassive range as well.

  9. Matter and Energy

    CERN Document Server

    Karam, P Andrew

    2011-01-01

    In Matter and Energy, readers will learn about the many forms of energy, the wide variety of particles in nature, and Albert Einstein's world-changing realization of how matter can be changed into pure energy. The book also examines the recent discoveries of dark matter and dark energy and the future of the universe.

  10. The role of fossil organic matter in the ecosystem development of post-mining sites revealed by isotope analyses

    Science.gov (United States)

    Jandova, Katerina; Hyodo, Fujio; Vindušková, Olga; Moradi, Jabbar; Frouz, Jan

    2017-04-01

    Sediments rich in kerogen ( 19 Ma old, 14C-free) are present in the overburden at post-mining area in Western Bohemia, near Sokolov city, the Czech Republic. There are two successional chronosequences, an alder reclamation and spontaneous succession, consisting of sites that differ in time since heaping. Both chronosequences accumulate recent organic matter over time, although the process is initially faster at reclamation. We hypothesized that (i) radiocarbon age of soil organic matter would be decreasing with time since spoil heaping; (ii) the detrital food web would show the assimilation of fossil carbon by heterotrophic organisms in the initial stages of succession when fossil organic matter is the predominant source of carbon; (iii) the isotopic track of fossil organic matter in the detrital food web would be more prominent at sites with lower vegetation cover and litter production. Nitrogen isotopic ratios of soils were high at the young sites and the decrease in δ15N was correlated with the increase in content of recent organic carbon. Nitrogen isotopic ratios of soil detritivores equalled to that of tree leaves at reclamation but were higher at successional sites. Possibly, other food sources were used apart from tree leaves litter at the latter. Interestingly, soil animals but not primary producers were 14C depleted in the youngest relative to the oldest sites. The depletion in 14C of detritivores relative to primary producers was likely due to the geophagy behaviour of the millipedes at the young sites where fossil organic matter is the largest carbon pool.

  11. Secretly asymmetric dark matter

    Science.gov (United States)

    Agrawal, Prateek; Kilic, Can; Swaminathan, Sivaramakrishnan; Trendafilova, Cynthia

    2017-01-01

    We study a mechanism where the dark matter number density today arises from asymmetries generated in the dark sector in the early Universe, even though the total dark matter number remains zero throughout the history of the Universe. The dark matter population today can be completely symmetric, with annihilation rates above those expected from thermal weakly interacting massive particles. We give a simple example of this mechanism using a benchmark model of flavored dark matter. We discuss the experimental signatures of this setup, which arise mainly from the sector that annihilates the symmetric component of dark matter.

  12. Dark Matter Caustics

    International Nuclear Information System (INIS)

    Natarajan, Aravind

    2010-01-01

    The continuous infall of dark matter with low velocity dispersion in galactic halos leads to the formation of high density structures called caustics. Dark matter caustics are of two kinds : outer and inner. Outer caustics are thin spherical shells surrounding galaxies while inner caustics have a more complicated structure that depends on the dark matter angular momentum distribution. The presence of a dark matter caustic in the plane of the galaxy modifies the gas density in its neighborhood which may lead to observable effects. Caustics are also relevant to direct and indirect dark matter searches.

  13. Dark Matter Searches

    International Nuclear Information System (INIS)

    Moriyama, Shigetaka

    2008-01-01

    Recent cosmological as well as historical observations of rotational curves of galaxies strongly suggest the existence of dark matter. It is also widely believed that dark matter consists of unknown elementary particles. However, astrophysical observations based on gravitational effects alone do not provide sufficient information on the properties of dark matter. In this study, the status of dark matter searches is investigated by observing high-energy neutrinos from the sun and the earth and by observing nuclear recoils in laboratory targets. The successful detection of dark matter by these methods facilitates systematic studies of its properties. Finally, the XMASS experiment, which is due to start at the Kamioka Observatory, is introduced

  14. Impeded Dark Matter

    Energy Technology Data Exchange (ETDEWEB)

    Kopp, Joachim; Liu, Jia [PRISMA Cluster of Excellence & Mainz Institute for Theoretical Physics,Johannes Gutenberg University,Staudingerweg 7, 55099 Mainz (Germany); Slatyer, Tracy R. [Center for Theoretical Physics, Massachusetts Institute of Technology,Cambridge, MA 02139 (United States); Wang, Xiao-Ping [PRISMA Cluster of Excellence & Mainz Institute for Theoretical Physics,Johannes Gutenberg University,Staudingerweg 7, 55099 Mainz (Germany); Xue, Wei [Center for Theoretical Physics, Massachusetts Institute of Technology,Cambridge, MA 02139 (United States)

    2016-12-12

    We consider dark matter models in which the mass splitting between the dark matter particles and their annihilation products is tiny. Compared to the previously proposed Forbidden Dark Matter scenario, the mass splittings we consider are much smaller, and are allowed to be either positive or negative. To emphasize this modification, we dub our scenario “Impeded Dark Matter”. We demonstrate that Impeded Dark Matter can be easily realized without requiring tuning of model parameters. For negative mass splitting, we demonstrate that the annihilation cross-section for Impeded Dark Matter depends linearly on the dark matter velocity or may even be kinematically forbidden, making this scenario almost insensitive to constraints from the cosmic microwave background and from observations of dwarf galaxies. Accordingly, it may be possible for Impeded Dark Matter to yield observable signals in clusters or the Galactic center, with no corresponding signal in dwarfs. For positive mass splitting, we show that the annihilation cross-section is suppressed by the small mass splitting, which helps light dark matter to survive increasingly stringent constraints from indirect searches. As specific realizations for Impeded Dark Matter, we introduce a model of vector dark matter from a hidden SU(2) sector, and a composite dark matter scenario based on a QCD-like dark sector.

  15. Impeded Dark Matter

    International Nuclear Information System (INIS)

    Kopp, Joachim; Liu, Jia; Slatyer, Tracy R.; Wang, Xiao-Ping; Xue, Wei

    2016-01-01

    We consider dark matter models in which the mass splitting between the dark matter particles and their annihilation products is tiny. Compared to the previously proposed Forbidden Dark Matter scenario, the mass splittings we consider are much smaller, and are allowed to be either positive or negative. To emphasize this modification, we dub our scenario “Impeded Dark Matter”. We demonstrate that Impeded Dark Matter can be easily realized without requiring tuning of model parameters. For negative mass splitting, we demonstrate that the annihilation cross-section for Impeded Dark Matter depends linearly on the dark matter velocity or may even be kinematically forbidden, making this scenario almost insensitive to constraints from the cosmic microwave background and from observations of dwarf galaxies. Accordingly, it may be possible for Impeded Dark Matter to yield observable signals in clusters or the Galactic center, with no corresponding signal in dwarfs. For positive mass splitting, we show that the annihilation cross-section is suppressed by the small mass splitting, which helps light dark matter to survive increasingly stringent constraints from indirect searches. As specific realizations for Impeded Dark Matter, we introduce a model of vector dark matter from a hidden SU(2) sector, and a composite dark matter scenario based on a QCD-like dark sector.

  16. Collapsed Dark Matter Structures.

    Science.gov (United States)

    Buckley, Matthew R; DiFranzo, Anthony

    2018-02-02

    The distributions of dark matter and baryons in the Universe are known to be very different: The dark matter resides in extended halos, while a significant fraction of the baryons have radiated away much of their initial energy and fallen deep into the potential wells. This difference in morphology leads to the widely held conclusion that dark matter cannot cool and collapse on any scale. We revisit this assumption and show that a simple model where dark matter is charged under a "dark electromagnetism" can allow dark matter to form gravitationally collapsed objects with characteristic mass scales much smaller than that of a Milky-Way-type galaxy. Though the majority of the dark matter in spiral galaxies would remain in the halo, such a model opens the possibility that galaxies and their associated dark matter play host to a significant number of collapsed substructures. The observational signatures of such structures are not well explored but potentially interesting.

  17. Collapsed Dark Matter Structures

    Science.gov (United States)

    Buckley, Matthew R.; DiFranzo, Anthony

    2018-02-01

    The distributions of dark matter and baryons in the Universe are known to be very different: The dark matter resides in extended halos, while a significant fraction of the baryons have radiated away much of their initial energy and fallen deep into the potential wells. This difference in morphology leads to the widely held conclusion that dark matter cannot cool and collapse on any scale. We revisit this assumption and show that a simple model where dark matter is charged under a "dark electromagnetism" can allow dark matter to form gravitationally collapsed objects with characteristic mass scales much smaller than that of a Milky-Way-type galaxy. Though the majority of the dark matter in spiral galaxies would remain in the halo, such a model opens the possibility that galaxies and their associated dark matter play host to a significant number of collapsed substructures. The observational signatures of such structures are not well explored but potentially interesting.

  18. Sterile neutrino dark matter

    CERN Document Server

    Merle, Alexander

    2017-01-01

    This book is a new look at one of the hottest topics in contemporary science, Dark Matter. It is the pioneering text dedicated to sterile neutrinos as candidate particles for Dark Matter, challenging some of the standard assumptions which may be true for some Dark Matter candidates but not for all. So, this can be seen either as an introduction to a specialized topic or an out-of-the-box introduction to the field of Dark Matter in general. No matter if you are a theoretical particle physicist, an observational astronomer, or a ground based experimentalist, no matter if you are a grad student or an active researcher, you can benefit from this text, for a simple reason: a non-standard candidate for Dark Matter can teach you a lot about what we truly know about our standard picture of how the Universe works.

  19. Silagem de sorgo de porte baixo com diferentes teores de tanino e de umidade no colmo.I - pH e teores de matéria seca e de ácidos graxos durante a fermentação Forage sorghum silage with different tannin concentration and moisture in the stem. I - Dry matter concentration, pH and fat acids during fermentation

    Directory of Open Access Journals (Sweden)

    N.M. Rodriguez

    1999-10-01

    Full Text Available Quatro híbridos de porte baixo, com diferentes teores de tanino e de umidade no colmo, foram ensilados em silos de laboratório feitos de tubos "PVC", e abertos após 1 (P2, 7 (P3, 14 (P4, 28 (P5 e 56 (P6 dias, para estudo da fermentação e da variação no teor de matéria seca. Foram usados 24 tratamentos com quatro repetições cada, sendo quatro híbridos (T1=colmo suculento e baixo tanino, T2=colmo seco e baixo tanino, T3=colmo seco e alto tanino, T4= colmo suculento e alto tanino combinados com seis tempos para abertura do silo, sendo o primeiro tempo antes de ensilar (P1. Foram determinados os teores de matéria seca (MS, perdas de matéria seca, ácidos graxos voláteis, ácido láctico e pH. As diferenças foram verificadas pelo teste de Tukey. As silagens estabilizaram-se entre P4 e P5. As silagens dos híbridos T1 e T2 apresentaram menores teores de MS e de acetato que T3 e T4. A correlação entre tanino e acetato foi de 0,36 (PFour hybrid forage sorghums with different tannin concentrations and moisture in the stem were ensiled in laboratory silos made of "PVC" tubes. The silos were opened after 1 (P2, 7 (P3, 14 (P4, 28 (P5 e 56 (P6 days after ensiling, in order to evaluate fermentation patterns and other silage characteristics. Twenty-four treatments were used, with four repetitions each: four hybrids (T1=moist stem/low tannin, T2=not moist stem/low tannin, T3=not moist stem/high tannin, T4= moist stem/high tannin and with six periods, since the forages before ensiling (P1 were also studied. Dry matter content (DM, dry matter losses, pH, lactic acid and volatile fat acids were determined. Data were evaluated by analysis of variance, with mean separation achieved using Tukey statistical test. The stability was achieved between P4 and P5. T1 and T2 had lower DM content and acetate than T3 and T4. All silages showed good fermentation patterns.

  20. Strategies for dark matter detection

    International Nuclear Information System (INIS)

    Silk, J.

    1988-01-01

    The present status of alternative forms of dark matter, both baryonic and nonbaryonic, is reviewed. Alternative arguments are presented for the predominance of either cold dark matter (CDM) or of baryonic dark matter (BDM). Strategies are described for dark matter detection, both for dark matter that consists of weakly interacting relic particles and for dark matter that consists of dark stellar remnants

  1. Dike intrusions into bituminous coal, Illinois Basin: H, C, N, O isotopic responses to rapid and brief heating

    Science.gov (United States)

    Schimmelmann, A.; Mastalerz, Maria; Gao, L.; Sauer, P.E.; Topalov, K.

    2009-01-01

    Unlike long-term heating in subsiding sedimentary basins, the near-instantaneous thermal maturation of sedimentary organic matter near magmatic intrusions is comparable to artificial thermal maturation in the laboratory in terms of short duration and limited extent. This study investigates chemical and H, C, N, O isotopic changes in high volatile bituminous coal near two Illinois dike contacts and compares observed patterns and trends with data from other published studies and from artificial maturation experiments. Our study pioneers in quantifying isotopically exchangeable hydrogen and measuring the D/H (i.e., 2H/1H) ratio of isotopically non-exchangeable organic hydrogen in kerogen near magmatic contacts. Thermal stress in coal caused a reduction of isotopically exchangeable hydrogen in kerogen from 5% to 6% in unaltered coal to 2-3% at contacts, mostly due to elimination of functional groups (e.g., {single bond}OH, {single bond}COOH, {single bond}NH2). In contrast to all previously published data on D/H in thermally matured organic matter, the more mature kerogen near the two dike contacts is D-depleted, which is attributed to (i) thermal elimination of D-enriched functional groups, and (ii) thermal drying of hydrologically isolated coal prior to the onset of cracking reactions, thereby precluding D-transfer from relatively D-enriched water into kerogen. Maxima in organic nitrogen concentration and in the atomic N/C ratio of kerogen at a distance of ???2.5 to ???3.5 m from the thicker dike indicate that reactive N-compounds had been pyrolytically liberated at high temperature closer to the contact, migrated through the coal seam, and recombined with coal kerogen in a zone of lower temperature. The same principle extends to organic carbon, because a strong ??13Ckerogen vs. ??15Nkerogen correlation across 5.5 m of coal adjacent to the thicker dike indicates that coal was functioning as a flow-through reactor along a dynamic thermal gradient facilitating back

  2. Artificial maturation of an immature sulfur- and organic matter-rich limestone from the Ghareb Formation, Jordan

    Science.gov (United States)

    Koopmans, M.P.; Rijpstra, W.I.C.; De Leeuw, J. W.; Lewan, M.D.; Damste, J.S.S.

    1998-01-01

    An immature (Ro=0.39%), S-rich (S(org)/C = 0.07), organic matter-rich (19.6 wt. % TOC) limestone from the Ghareb Formation (Upper Cretaceous) in Jordan was artificially matured by hydrous pyrolysis (200, 220 ..., 300??C; 72 h) to study the effect of progressive diagenesis and early catagenesis on the amounts and distributions of hydrocarbons, organic sulfur compounds and S-rich geomacromolecules. The use of internal standards allowed the determination of absolute amounts. With increasing thermal maturation, large amounts of alkanes and alkylthiophenes with predominantly linear carbon skeletons are generated from the kerogen. The alkylthiophene isomer distributions do not change significantly with increasing thermal maturation, indicating the applicability of alkylthiophenes as biomarkers at relatively high levels of thermal maturity. For a given carbon skeleton, the saturated hydrocarbon, alkylthiophenes and alkylbenzo[b]thiophenes are stable forms at relatively high temperatures, whereas the alkylsulfides are not stable. The large amount of alkylthiophenes produced relative to the alkanes may be explained by the large number of monosulfide links per carbon skeleton. These results are in good agreement with those obtained previously for an artificial maturation series of an immature S-rich sample from the Gessoso-solfifera Formation.An immature (Ro = 0.39%), S-rich (Sorg/C = 0.07), organic matter-rich (19.6 wt.% TOC) limestone from the Ghareb Formation (Upper Cretaceous) in Jordan was artificially matured by hydrous pyrolysis (200, 220, ..., 300??C; 72 h) to study the effect of progressive diagenesis and early catagenesis on the amounts and distributions of hydrocarbons, organic sulfur compounds and S-rich geomacromolecules. The use of internal standards allowed the determination of absolute amounts. With increasing thermal maturation, large amounts of alkanes and alkylthiophenes with predominantly linear carbon skeletons are generated from the kerogen. The

  3. Stars of strange matter

    International Nuclear Information System (INIS)

    Bethe, H.A.; Brown, G.E.; Cooperstein, J.

    1987-01-01

    We investigate suggestions that quark matter with strangeness per baryon of order unity may be stable. We model this matter at nuclear matter densities as a gas of close packed Λ-particles. From the known mass of the Λ-particle we obtain an estimate of the energy and chemical potential of strange matter at nuclear densities. These are sufficiently high to preclude any phase transition from neutron matter to strange matter in the region near nucleon matter density. Including effects from gluon exchange phenomenologically, we investigate higher densities, consistently making approximations which underestimate the density of transition. In this way we find a transition density ρ tr > or approx.7ρ 0 , where ρ 0 is nuclear matter density. This is not far from the maximum density in the center of the most massive neutron stars that can be constructed. Since we have underestimated ρ tr and still find it to be ∝7ρ 0 , we do not believe that the transition from neutron to quark matter is likely in neutron stars. Moreover, measured masses of observed neutron stars are ≅1.4 M sun , where M sun is the solar mass. For such masses, the central (maximum) density is ρ c 0 . Transition to quark matter is certainly excluded for these densities. (orig.)

  4. Hidden charged dark matter

    International Nuclear Information System (INIS)

    Feng, Jonathan L.; Kaplinghat, Manoj; Tu, Huitzu; Yu, Hai-Bo

    2009-01-01

    Can dark matter be stabilized by charge conservation, just as the electron is in the standard model? We examine the possibility that dark matter is hidden, that is, neutral under all standard model gauge interactions, but charged under an exact (\\rm U)(1) gauge symmetry of the hidden sector. Such candidates are predicted in WIMPless models, supersymmetric models in which hidden dark matter has the desired thermal relic density for a wide range of masses. Hidden charged dark matter has many novel properties not shared by neutral dark matter: (1) bound state formation and Sommerfeld-enhanced annihilation after chemical freeze out may reduce its relic density, (2) similar effects greatly enhance dark matter annihilation in protohalos at redshifts of z ∼ 30, (3) Compton scattering off hidden photons delays kinetic decoupling, suppressing small scale structure, and (4) Rutherford scattering makes such dark matter self-interacting and collisional, potentially impacting properties of the Bullet Cluster and the observed morphology of galactic halos. We analyze all of these effects in a WIMPless model in which the hidden sector is a simplified version of the minimal supersymmetric standard model and the dark matter is a hidden sector stau. We find that charged hidden dark matter is viable and consistent with the correct relic density for reasonable model parameters and dark matter masses in the range 1 GeV ∼ X ∼< 10 TeV. At the same time, in the preferred range of parameters, this model predicts cores in the dark matter halos of small galaxies and other halo properties that may be within the reach of future observations. These models therefore provide a viable and well-motivated framework for collisional dark matter with Sommerfeld enhancement, with novel implications for astrophysics and dark matter searches

  5. Organic and Inorganic Matter in Louisiana Coastal Waters: Vermilion, Atchafalaya, Terrebonne, Barataria, and Mississippi Regions.

    Science.gov (United States)

    Chromophoric dissolved organic matter (CDOM) spectral absorption, dissolved organic carbon (DOC) concentration, and the particulate fraction of inorganic (PIM) and organic matter (POM) were measured in Louisiana coastal waters at Vermilion, Atchafalaya, Terrebonne, Barataria, and...

  6. Codecaying Dark Matter.

    Science.gov (United States)

    Dror, Jeff Asaf; Kuflik, Eric; Ng, Wee Hao

    2016-11-18

    We propose a new mechanism for thermal dark matter freeze-out, called codecaying dark matter. Multicomponent dark sectors with degenerate particles and out-of-equilibrium decays can codecay to obtain the observed relic density. The dark matter density is exponentially depleted through the decay of nearly degenerate particles rather than from Boltzmann suppression. The relic abundance is set by the dark matter annihilation cross section, which is predicted to be boosted, and the decay rate of the dark sector particles. The mechanism is viable in a broad range of dark matter parameter space, with a robust prediction of an enhanced indirect detection signal. Finally, we present a simple model that realizes codecaying dark matter.

  7. Diseases of white matter

    International Nuclear Information System (INIS)

    Holland, B.A.

    1987-01-01

    The diagnosis of white matter abnormalities was revolutionized by the advent of computed tomography (CT), which provided a noninvasive method of detection and assessment of progression of a variety of white matter processes. However, the inadequacies of CT were recognized early, including its relative insensitivity to small foci of abnormal myelin in the brain when correlated with autopsy findings and its inability to image directly white matter diseases of the spinal cord. Magnetic resonance imaging (MRI), on the other hand, sensitive to the slight difference in tissue composition of normal gray and white matter and to subtle increase in water content associated with myelin disorders, is uniquely suited for the examination of white matter pathology. Its clinical applications include the evaluation of the normal process of myelination in childhood and the various white matter diseases, including disorders of demyelination and dysmyelination

  8. Detecting dark matter

    International Nuclear Information System (INIS)

    Dixon, Roger L.

    2000-01-01

    Dark matter is one of the most pressing problems in modern cosmology and particle physic research. This talk will motivate the existence of dark matter by reviewing the main experimental evidence for its existence, the rotation curves of galaxies and the motions of galaxies about one another. It will then go on to review the corroborating theoretical motivations before combining all the supporting evidence to explore some of the possibilities for dark matter along with its expected properties. This will lay the ground work for dark matter detection. A number of differing techniques are being developed and used to detect dark matter. These will be briefly discussed before the focus turns to cryogenic detection techniques. Finally, some preliminary results and expectations will be given for the Cryogenic Dark Matter Search (CDMS) experiment

  9. Clumpy cold dark matter

    Science.gov (United States)

    Silk, Joseph; Stebbins, Albert

    1993-01-01

    A study is conducted of cold dark matter (CDM) models in which clumpiness will inhere, using cosmic strings and textures suited to galaxy formation. CDM clumps of 10 million solar mass/cu pc density are generated at about z(eq) redshift, with a sizable fraction surviving. Observable implications encompass dark matter cores in globular clusters and in galactic nuclei. Results from terrestrial dark matter detection experiments may be affected by clumpiness in the Galactic halo.

  10. Dark matter haloes: a multistream view

    Science.gov (United States)

    Ramachandra, Nesar S.; Shandarin, Sergei F.

    2017-09-01

    Mysterious dark matter constitutes about 85 per cent of all masses in the Universe. Clustering of dark matter plays a dominant role in the formation of all observed structures on scales from a fraction to a few hundreds of Mega-parsecs. Galaxies play a role of lights illuminating these structures so they can be observed. The observations in the last several decades have unveiled opulent geometry of these structures currently known as the cosmic web. Haloes are the highest concentrations of dark matter and host luminous galaxies. Currently the most accurate modelling of dark matter haloes is achieved in cosmological N-body simulations. Identifying the haloes from the distribution of particles in N-body simulations is one of the problems attracting both considerable interest and efforts. We propose a novel framework for detecting potential dark matter haloes using the field unique for dark matter-multistream field. The multistream field emerges at the non-linear stage of the growth of perturbations because the dark matter is collisionless. Counting the number of velocity streams in gravitational collapses supplements our knowledge of spatial clustering. We assume that the virialized haloes have convex boundaries. Closed and convex regions of the multistream field are hence isolated by imposing a positivity condition on all three eigenvalues of the Hessian estimated on the smoothed multistream field. In a single-scale analysis of high multistream field resolution and low softening length, the halo substructures with local multistream maxima are isolated as individual halo sites.

  11. Hybrid Dark Matter

    OpenAIRE

    Chao, Wei

    2018-01-01

    Dark matter can be produced in the early universe via the freeze-in or freeze-out mechanisms. Both scenarios were investigated in references, but the production of dark matters via the combination of these two mechanisms are not addressed. In this paper we propose a hybrid dark matter model where dark matters have two components with one component produced thermally and the other one produced non-thermally. We present for the first time the analytical calculation for the relic abundance of th...

  12. The quark matter

    International Nuclear Information System (INIS)

    Rho, Mannque.

    1980-04-01

    The present status of our understanding of the physics of hadronic (nuclear or neutron) matter under extreme conditions, in particular at high densities is discussed. This is a problem which challenges three disciplines of physics: nuclear physics, astrophysics and particle physics. It is generally believed that we now have a correct and perhaps ultimate theory of the strong interactions, namely quantum chromodynamics (QCD). The constituents of this theory are quarks and gluons, so highly dense matters should be describable in terms of these constituents alone. This is a question that addresses directly to the phenomenon of quark confinement, one of the least understood aspects in particle physics. For nuclear physics, the possibility of a phase change between nuclear matter and quark matter introduces entirely new degrees of freedom in the description of nuclei and will bring perhaps a deeper understanding of nuclear dynamics. In astrophysics, the properties of neutron stars will be properly understood only when the equation of state of 'neutron' matter at densities exceeding that of nuclear matter can be realiably calculated. Most fascinating is the possibility of quark stars existing in nature, not entirely an absurd idea. Finally the quark matter - nuclear matter phase transition must have occured in the early stage of universe when matter expanded from high temperature and density; this could be an essential ingredient in the big-bang cosmology

  13. Soft matter physics

    CERN Document Server

    Doi, Masao

    2013-01-01

    Soft matter (polymers, colloids, surfactants and liquid crystals) are an important class of materials in modern technology. They also form the basis of many future technologies, for example in medical and environmental applications. Soft matter shows complex behaviour between fluids and solids, and used to be a synonym of complex materials. Due to the developments of the past two decades, soft condensed matter can now be discussed on the same sound physical basis as solid condensedmatter. The purpose of this book is to provide an overview of soft matter for undergraduate and graduate students

  14. Searching for dark matter

    Science.gov (United States)

    Mateo, Mario

    1994-01-01

    Three teams of astronomers believe they have independently found evidence for dark matter in our galaxy. A brief history of the search for dark matter is presented. The use of microlensing-event observation for spotting dark matter is described. The equipment required to observe microlensing events and three groups working on dark matter detection are discussed. The three groups are the Massive Compact Halo Objects (MACHO) Project team, the Experience de Recherche d'Objets Sombres (EROS) team, and the Optical Gravitational Lensing Experiment (OGLE) team. The first apparent detections of microlensing events by the three teams are briefly reported.

  15. Characterization of Particulate Matter Concentrations during Controlled Indoor Activities

    Czech Academy of Sciences Publication Activity Database

    Glytsos, T.; Ondráček, Jakub; Ondráčková, Lucie; Kopanakis, I.; Lazaridis, M.

    2010-01-01

    Roč. 44, č. 12 (2010), s. 1539-1549 ISSN 1352-2310 Grant - others:MTDK(XE) CT/2004/513849 Institutional research plan: CEZ:AV0Z40720504 Keywords : indoor sources * number size distribution * emission rates Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.226, year: 2010

  16. Trace Metals Concentration Assessment in Urban Particulate Matter ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Principal component analysis revealed that major sources of trace metals in ambient air ... contributed by earth crust and windblown soil .... Source Apportionment: To probe the origin of trace .... atmospheric accumulation of heavy metals and.

  17. The investigation of atmospheric particulate matter pollution in Suzhou

    International Nuclear Information System (INIS)

    Chen Yi'ou; Zhang Yuliang; Wang Ya; Wang Pei; Tian Hailin

    2012-01-01

    Objective: To investigate the pollution status, vertical distribution and concentration variation within 24 hours of total suspended particles (TSPs), particulate matter ≤10 μm (PM10), particulate matter ≤5 (PM5) and particulate matter ≤2.5 μm (PM2.5) in major functional areas of Suzhou and the protective effect of different type masks on particulate matter. Methods: (1) The concentration of atmospheric TSPs, PM10, PM5 and PM2.5 in seven functional areas in Suzhou was monitored for three consecutive days. (2) A residential building of 25 stories was chosen and the concentration of TSPs, PM10, PM5, PM2.5 was detected at the 1st, 5th, 10th, 15th, 20 th and the 25th floor respectively. (3) The concentrations of the four particulate matter were detected every two-hours for three consecutive days to investigate how concentration of particulate matter varies within 24 hours. (4) The concentration of the four kinds of particulate matter was analyzed with the sampling head of monitor wrapped with disposable non-woven medical mask, fashion-type mask, gauze mask or activated carbon anti-dust mask respectively, and the protective effect of the four masks on particulate matter was compared. Results: (1) The concentration of PM2.5 was higher than the national health limit in all seven functional areas in Suzhou. (2) No significant difference in vertical distribution of particulate matter was found among different floors in residential buildings (P>0.05). (3) Two small peaks of particulate matter appeared in the morning and evening respectively while the top appeared at dawn (P< 0.05). (4) Disposable non-woven medical mask showed the best protective effect on particulate matter among the four tested masks. Conclusion: PM2.5 is the main particulate matter in Suzhou area. In addition the 4 kinds of particulate matter: TSP, PM10, PM5 and PM2.5 are of higher concentration in the early morning. No significant difference was detected from an altitude of less than 75 meters

  18. Nuclear and quark matter at high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Biro, Tamas S. [H.A.S. Wigner Research Centre for Physics, Budapest (Hungary); Jakovac, Antal [Roland Eotvos University, Budapest (Hungary); Schram, Zsolt [University of Debrecen, Institute for Theoretical Physics, Debrecen (Hungary)

    2017-03-15

    We review important ideas on nuclear and quark matter description on the basis of high-temperature field theory concepts, like resummation, dimensional reduction, interaction scale separation and spectral function modification in media. Statistical and thermodynamical concepts are spotted in the light of these methods concentrating on the -partially still open- problems of the hadronization process. (orig.)

  19. Optimal concentrations in transport systems

    Science.gov (United States)

    Jensen, Kaare H.; Kim, Wonjung; Holbrook, N. Michele; Bush, John W. M.

    2013-01-01

    Many biological and man-made systems rely on transport systems for the distribution of material, for example matter and energy. Material transfer in these systems is determined by the flow rate and the concentration of material. While the most concentrated solutions offer the greatest potential in terms of material transfer, impedance typically increases with concentration, thus making them the most difficult to transport. We develop a general framework for describing systems for which impedance increases with concentration, and consider material flow in four different natural systems: blood flow in vertebrates, sugar transport in vascular plants and two modes of nectar drinking in birds and insects. The model provides a simple method for determining the optimum concentration copt in these systems. The model further suggests that the impedance at the optimum concentration μopt may be expressed in terms of the impedance of the pure (c = 0) carrier medium μ0 as μopt∼2αμ0, where the power α is prescribed by the specific flow constraints, for example constant pressure for blood flow (α = 1) or constant work rate for certain nectar-drinking insects (α = 6). Comparing the model predictions with experimental data from more than 100 animal and plant species, we find that the simple model rationalizes the observed concentrations and impedances. The model provides a universal framework for studying flows impeded by concentration, and yields insight into optimization in engineered systems, such as traffic flow. PMID:23594815

  20. Dark matter and cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Schramm, D.N.

    1992-03-01

    The cosmological dark matter problem is reviewed. The Big Bang Nucleosynthesis constraints on the baryon density are compared with the densities implied by visible matter, dark halos, dynamics of clusters, gravitational lenses, large-scale velocity flows, and the {Omega} = 1 flatness/inflation argument. It is shown that (1) the majority of baryons are dark; and (2) non-baryonic dark matter is probably required on large scales. It is also noted that halo dark matter could be either baryonic or non-baryonic. Descrimination between ``cold`` and ``hot`` non-baryonic candidates is shown to depend on the assumed ``seeds`` that stimulate structure formation. Gaussian density fluctuations, such as those induced by quantum fluctuations, favor cold dark matter, whereas topological defects such as strings, textures or domain walls may work equally or better with hot dark matter. A possible connection between cold dark matter, globular cluster ages and the Hubble constant is mentioned. Recent large-scale structure measurements, coupled with microwave anisotropy limits, are shown to raise some questions for the previously favored density fluctuation picture. Accelerator and underground limits on dark matter candidates are also reviewed.

  1. Dark matter and cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Schramm, D.N.

    1992-03-01

    The cosmological dark matter problem is reviewed. The Big Bang Nucleosynthesis constraints on the baryon density are compared with the densities implied by visible matter, dark halos, dynamics of clusters, gravitational lenses, large-scale velocity flows, and the {Omega} = 1 flatness/inflation argument. It is shown that (1) the majority of baryons are dark; and (2) non-baryonic dark matter is probably required on large scales. It is also noted that halo dark matter could be either baryonic or non-baryonic. Descrimination between cold'' and hot'' non-baryonic candidates is shown to depend on the assumed seeds'' that stimulate structure formation. Gaussian density fluctuations, such as those induced by quantum fluctuations, favor cold dark matter, whereas topological defects such as strings, textures or domain walls may work equally or better with hot dark matter. A possible connection between cold dark matter, globular cluster ages and the Hubble constant is mentioned. Recent large-scale structure measurements, coupled with microwave anisotropy limits, are shown to raise some questions for the previously favored density fluctuation picture. Accelerator and underground limits on dark matter candidates are also reviewed.

  2. Superball dark matter

    CERN Document Server

    Kusenko, A

    1999-01-01

    Supersymmetric models predict a natural dark-matter candidate, stable baryonic Q-balls. They could be copiously produced in the early Universe as a by-product of the Affleck-Dine baryogenesis. I review the cosmological and astrophysical implications, methods of detection, and the present limits on this form of dark matter.

  3. Baryonic Dark Matter

    OpenAIRE

    De Paolis, F.; Jetzer, Ph.; Ingrosso, G.; Roncadelli, M.

    1997-01-01

    Reasons supporting the idea that most of the dark matter in galaxies and clusters of galaxies is baryonic are discussed. Moreover, it is argued that most of the dark matter in galactic halos should be in the form of MACHOs and cold molecular clouds.

  4. Dark matter detection - II

    International Nuclear Information System (INIS)

    Zacek, Viktor

    2015-01-01

    The quest for the mysterious missing mass of the universe has become one of the big challenges of today's particle physics and cosmology. Astronomical observations show that only 1% of the matter of the universe is luminous. Moreover there is now convincing evidence that 85% of all gravitationally observable matter in the universe is of a new exotic kind, different from the 'ordinary' matter surrounding us. In a series of three lectures we discuss past, recent and future efforts made world-wide to detect and/or decipher the nature of Dark Matter. In Lecture I we review our present knowledge of the Dark Matter content of the Universe and how experimenters search for it's candidates; In Lecture II we discuss so-called 'direct detection' techniques which allow to search for scattering of galactic dark matter particles with detectors in deep-underground laboratories; we discuss the interpretation of experimental results and the challenges posed by different backgrounds; In Lecture III we take a look at the 'indirect detection' of the annihilation of dark matter candidates in astrophysical objects, such as our sun or the center of the Milky Way; In addition we will have a look at efforts to produce Dark Matter particles directly at accelerators and we shall close with a look at alternative nonparticle searches and future prospects. (author)

  5. Dark matter and cosmology

    International Nuclear Information System (INIS)

    Schramm, D.N.

    1992-03-01

    The cosmological dark matter problem is reviewed. The Big Bang Nucleosynthesis constraints on the baryon density are compared with the densities implied by visible matter, dark halos, dynamics of clusters, gravitational lenses, large-scale velocity flows, and the Ω = 1 flatness/inflation argument. It is shown that (1) the majority of baryons are dark; and (2) non-baryonic dark matter is probably required on large scales. It is also noted that halo dark matter could be either baryonic or non-baryonic. Descrimination between ''cold'' and ''hot'' non-baryonic candidates is shown to depend on the assumed ''seeds'' that stimulate structure formation. Gaussian density fluctuations, such as those induced by quantum fluctuations, favor cold dark matter, whereas topological defects such as strings, textures or domain walls may work equally or better with hot dark matter. A possible connection between cold dark matter, globular cluster ages and the Hubble constant is mentioned. Recent large-scale structure measurements, coupled with microwave anisotropy limits, are shown to raise some questions for the previously favored density fluctuation picture. Accelerator and underground limits on dark matter candidates are also reviewed

  6. Matter in transition

    International Nuclear Information System (INIS)

    Anderson, Lara B.; Gray, James; Raghuram, Nikhil; Taylor, Washington

    2016-01-01

    We explore a novel type of transition in certain 6D and 4D quantum field theories, in which the matter content of the theory changes while the gauge group and other parts of the spectrum remain invariant. Such transitions can occur, for example, for SU(6) and SU(7) gauge groups, where matter fields in a three-index antisymmetric representation and the fundamental representation are exchanged in the transition for matter in the two-index antisymmetric representation. These matter transitions are realized by passing through superconformal theories at the transition point. We explore these transitions in dual F-theory and heterotic descriptions, where a number of novel features arise. For example, in the heterotic description the relevant 6D SU(7) theories are described by bundles on K3 surfaces where the geometry of the K3 is constrained in addition to the bundle structure. On the F-theory side, non-standard representations such as the three-index antisymmetric representation of SU(N) require Weierstrass models that cannot be realized from the standard SU(N) Tate form. We also briefly describe some other situations, with groups such as Sp(3), SO(12), and SU(3), where analogous matter transitions can occur between different representations. For SU(3), in particular, we find a matter transition between adjoint matter and matter in the symmetric representation, giving an explicit Weierstrass model for the F-theory description of the symmetric representation that complements another recent analogous construction.

  7. CONFERENCE: Quark matter 88

    International Nuclear Information System (INIS)

    Jacob, Maurice

    1988-01-01

    The 'Quark Matter' Conference caters for physicists studying nuclear matter under extreme conditions. The hope is that relativistic (high energy) heavy ion collisions allow formation of the long-awaited quark-gluon plasma, where the inter-quark 'colour' force is no longer confined inside nucleon-like dimensions

  8. Dark matter detection - I

    International Nuclear Information System (INIS)

    Zacek, Viktor

    2015-01-01

    The quest for the mysterious missing mass of the universe has become one of the big challenges of today's particle physics and cosmology. Astronomical observations show that only 1% of the matter of the universe is luminous. Moreover there is now convincing evidence that 85% of all gravitationally observable matter in the universe is of a new exotic kind, different from the 'ordinary' matter surrounding us. In a series of three lectures we discuss past, recent and future efforts made world-wide to detect and/or decipher the nature of Dark Matter. In Lecture I we review our present knowledge of the Dark Matter content of the Universe and how experimenters search for it's candidates; In Lecture II we discuss so-called 'direct detection' techniques which allow to search for scattering of galactic dark matter particles with detectors in deep-underground laboratories; we discuss the interpretation of experimental results and the challenges posed by different backgrounds; In Lecture III we take a look at the 'indirect detection' of the annihilation of dark matter candidates in astrophysical objects, such as our sun or the center of the Milky Way; In addition we will have a look at efforts to produce Dark Matter particles directly at accelerators and we shall close with a look at alternative nonparticle searches and future prospects. (author)

  9. Dark matter detection - III

    International Nuclear Information System (INIS)

    Zacek, Viktor

    2015-01-01

    The quest for the missing mass of the universe has become one of the big challenges of todays particle physics and cosmology. Astronomical observations show that only 1% of the matter of the Universe is luminous. Moreover there is now convincing evidence that 85% of all gravitationally observable matter in the Universe is of a new exotic kind, different from the 'ordinary' matter surrounding us. In a series of three lectures we discuss past, recent and future efforts made world- wide to detect and/or decipher the nature of Dark Matter. In Lecture I we review our present knowledge of the Dark Matter content of the Universe and how experimenters search for it's candidates; In Lecture II we discuss so-called 'direct detection' techniques which allow to search for scattering of galactic dark matter particles with detectors in deep-underground laboratories; we discuss the interpretation of experimental results and the challenges posed by different backgrounds; In Lecture III we take a look at the 'indirect detection' of the annihilation of dark matter candidates in astrophysical objects, such as our sun or the center of the Milky Way; In addition we will have a look at efforts to produce Dark Matter particles directly at accelerators and we shall close with a look at alternative nonparticle searches and future prospects. (author)

  10. Asymptotically Safe Dark Matter

    DEFF Research Database (Denmark)

    Sannino, Francesco; Shoemaker, Ian M.

    2015-01-01

    We introduce a new paradigm for dark matter (DM) interactions in which the interaction strength is asymptotically safe. In models of this type, the coupling strength is small at low energies but increases at higher energies, and asymptotically approaches a finite constant value. The resulting...... searches are the primary ways to constrain or discover asymptotically safe dark matter....

  11. Asymmetric dark matter

    International Nuclear Information System (INIS)

    Kaplan, David E.; Luty, Markus A.; Zurek, Kathryn M.

    2009-01-01

    We consider a simple class of models in which the relic density of dark matter is determined by the baryon asymmetry of the Universe. In these models a B-L asymmetry generated at high temperatures is transferred to the dark matter, which is charged under B-L. The interactions that transfer the asymmetry decouple at temperatures above the dark matter mass, freezing in a dark matter asymmetry of order the baryon asymmetry. This explains the observed relation between the baryon and dark matter densities for the dark matter mass in the range 5-15 GeV. The symmetric component of the dark matter can annihilate efficiently to light pseudoscalar Higgs particles a or via t-channel exchange of new scalar doublets. The first possibility allows for h 0 →aa decays, while the second predicts a light charged Higgs-like scalar decaying to τν. Direct detection can arise from Higgs exchange in the first model or a nonzero magnetic moment in the second. In supersymmetric models, the would-be lightest supersymmetric partner can decay into pairs of dark matter particles plus standard model particles, possibly with displaced vertices.

  12. Inelastic dark matter

    International Nuclear Information System (INIS)

    Smith, David; Weiner, Neal

    2001-01-01

    Many observations suggest that much of the matter of the universe is nonbaryonic. Recently, the DAMA NaI dark matter direct detection experiment reported an annual modulation in their event rate consistent with a WIMP relic. However, the Cryogenic Dark Matter Search (CDMS) Ge experiment excludes most of the region preferred by DAMA. We demonstrate that if the dark matter can only scatter by making a transition to a slightly heavier state (Δm∼100 keV), the experiments are no longer in conflict. Moreover, differences in the energy spectrum of nuclear recoil events could distinguish such a scenario from the standard WIMP scenario. Finally, we discuss the sneutrino as a candidate for inelastic dark matter in supersymmetric theories

  13. Baryonic dark matter

    International Nuclear Information System (INIS)

    Uson, Juan M.

    2000-01-01

    Many searches for baryonic dark matter have been conducted but, so far, all have been unsuccessful. Indeed, no more than 1% of the dark matter can be in the form of hydrogen burning stars. It has recently been suggested that most of the baryons in the universe are still in the form of ionized gas so that it is possible that there is no baryonic dark matter. Although it is likely that a significant fraction of the dark matter in the Milky Way is in a halo of non-baryonic matter, the data do not exclude the possibility that a considerable amount, perhaps most of it, could be in a tenuous halo of diffuse ionized gas

  14. Macro Dark Matter

    CERN Document Server

    Jacobs, David M; Lynn, Bryan W.

    2015-01-01

    Dark matter is a vital component of the current best model of our universe, $\\Lambda$CDM. There are leading candidates for what the dark matter could be (e.g. weakly-interacting massive particles, or axions), but no compelling observational or experimental evidence exists to support these particular candidates, nor any beyond-the-Standard-Model physics that might produce such candidates. This suggests that other dark matter candidates, including ones that might arise in the Standard Model, should receive increased attention. Here we consider a general class of dark matter candidates with characteristic masses and interaction cross-sections characterized in units of grams and cm$^2$, respectively -- we therefore dub these macroscopic objects as Macros. Such dark matter candidates could potentially be assembled out of Standard Model particles (quarks and leptons) in the early universe. A combination of earth-based, astrophysical, and cosmological observations constrain a portion of the Macro parameter space; ho...

  15. Dark matter universe.

    Science.gov (United States)

    Bahcall, Neta A

    2015-10-06

    Most of the mass in the universe is in the form of dark matter--a new type of nonbaryonic particle not yet detected in the laboratory or in other detection experiments. The evidence for the existence of dark matter through its gravitational impact is clear in astronomical observations--from the early observations of the large motions of galaxies in clusters and the motions of stars and gas in galaxies, to observations of the large-scale structure in the universe, gravitational lensing, and the cosmic microwave background. The extensive data consistently show the dominance of dark matter and quantify its amount and distribution, assuming general relativity is valid. The data inform us that the dark matter is nonbaryonic, is "cold" (i.e., moves nonrelativistically in the early universe), and interacts only weakly with matter other than by gravity. The current Lambda cold dark matter cosmology--a simple (but strange) flat cold dark matter model dominated by a cosmological constant Lambda, with only six basic parameters (including the density of matter and of baryons, the initial mass fluctuations amplitude and its scale dependence, and the age of the universe and of the first stars)--fits remarkably well all the accumulated data. However, what is the dark matter? This is one of the most fundamental open questions in cosmology and particle physics. Its existence requires an extension of our current understanding of particle physics or otherwise point to a modification of gravity on cosmological scales. The exploration and ultimate detection of dark matter are led by experiments for direct and indirect detection of this yet mysterious particle.

  16. The effects of increased phosphorus application on shoot dry matter ...

    African Journals Online (AJOL)

    The effects of increased phosphorus application on shoot dry matter, shoot P and Zn concentrations in wheat ( Triticum durum L.) and maize ( Zea mays L.)wheat ( Triticum durum L.) and maize ( Zea mays L.) grown in a calcareous soil.

  17. Non disturbing characterization and quantification of natural organic matter (NOM) contained in clay rock pore water by mass spectrometry using electro-spray and atmospheric pressure chemical ionization modes

    International Nuclear Information System (INIS)

    Huclier-Markai, S.; Landesman, C.; Grambow, B.; Rogniaux, H.; Monteau, F.; Vinsot, A.

    2010-01-01

    Document available in extended abstract form only. The Callovo-Oxfordian formation (COx) rock may contain up to 1% w/w of organic Carbon. Most of the Organic Matter (OM) is attached to the mineral particles whereas a small portion is present as Dissolved Organic Matter (DOM) in the pore water. In environmental studies, Natural Organic Matter (NOM) plays a key role on the bioavailability and the toxicity of metallic compounds. It is necessary to know the structure of any organic substance in order to assess which chemical and biological reactions occur under environmentally relevant conditions. The 150 Myears solid-bound organic matter of the COx (kerogen) has been already investigated in several studies and originates from a mixture of marine and terrestrial sources. In addition to this, the CCl 4 soluble organic fraction (bitumen) has been already characterized by liquid and gas chromatography coupled to mass spectrometry. It allows proportion and distribution of biological markers to be determined as polar compounds with aromatic and saturated hydrocarbons. DOM was extracted from a crushed clay rock of the COx formation with a high rock/water ratio of about 1500 g/L. Part of the OM from the COx is known to be sensitive to air oxidation which can significantly modify the nature of the bitumen by an overall shift towards lower molecular weight compounds. Therefore, the characteristics of the DOM must be determined in in-situ like conditions if one wants to assess the mobility of DOM in the clay pore space and to evaluate the mobility of heavy metals/ radionuclides. Due to their high binding capacity with metal ions and their colloidal sizes in natural waters, these macromolecules, through complexation reactions, might either enhance the mobility of trace elements, or reduce their migration rates by sorption processes in relation with their size and that of the porous medium. Consequently, the characterization of DOM in anoxic pore water samples from the COx

  18. Organic Matter in the Early Toarcian Shales, Paris Basin, France: a Response to Environmental Changes La matière organique dans les argiles du Toarcien inférieur du bassin de Paris, France : un enregistrement des changements d'environnement

    Directory of Open Access Journals (Sweden)

    Hollander D. J.

    2006-11-01

    Full Text Available A freshly drilled core from the Paris Basin contains a 16 m section of Early Toarcian Shale deposition. The organic matter and carbonates in these black-shale sediments were investigated using isotopic, petrologic and molecular organic geochemical methods. Throughout the studied section, molecular organic geochemical and organic petrographic characteristics remain remarkably uniform and suggest that the organic matter is overwhelmingly of marine origin (bacterial and algal with only minor contributions of terrigenous organic matter. In contrast, TOC content of the sediments, hydrogen indices of the kerogens, isotopic composition of co-existing kerogens and carbonates, and isotopic fractionation between the organic and inorganic carbon vary greatly and follow systematic trends. In general, higher values of hydrogen indices and TOC content are associated with the significantly depleted 13C values in both kerogens and carbonates and greater values of carbon isotopic fractionation. The integration of carbon isotopic fractionation between carbonates and kerogens (a proxy for surface water [CO2(aq] and hydrogen indices (a reflection of organic matter preservation suggests that the greatest accumulation of hydrocarbon-rich organic matter occurred at a time when surface water [CO2(aq] was extremely high. This implies that intermediate waters enriched in 12C-CO2 and [CO2(aq] were recycled into the photic zone of the surface water masses and provided the waters necessary to produce the observed negative isotopic excursions and maximum carbon isotopic fractionations. The settling of organic matter through a primarily anoxic water column with deposition in a highly reducing and quiescent bottom water mass was ideal for the extraordinary preservation of the organic matter. In turn, these results suggest that the depositional environment prevailing during the early Toarcian in the Paris Basin was a stratified-silled basin type environment. Si le cadre pal

  19. Exothermic dark matter

    International Nuclear Information System (INIS)

    Graham, Peter W.; Saraswat, Prashant; Harnik, Roni; Rajendran, Surjeet

    2010-01-01

    We propose a novel mechanism for dark matter to explain the observed annual modulation signal at DAMA/LIBRA which avoids existing constraints from every other dark matter direct detection experiment including CRESST, CDMS, and XENON10. The dark matter consists of at least two light states with mass ∼few GeV and splittings ∼5 keV. It is natural for the heavier states to be cosmologically long-lived and to make up an O(1) fraction of the dark matter. Direct detection rates are dominated by the exothermic reactions in which an excited dark matter state downscatters off of a nucleus, becoming a lower energy state. In contrast to (endothermic) inelastic dark matter, the most sensitive experiments for exothermic dark matter are those with light nuclei and low threshold energies. Interestingly, this model can also naturally account for the observed low-energy events at CoGeNT. The only significant constraint on the model arises from the DAMA/LIBRA unmodulated spectrum but it can be tested in the near future by a low-threshold analysis of CDMS-Si and possibly other experiments including CRESST, COUPP, and XENON100.

  20. Dark matter maps reveal cosmic scaffolding

    Energy Technology Data Exchange (ETDEWEB)

    Massey, R; Rhodes, J; Ellis, R; Scoville, N; Capak, P [CALTECH, Pasadena, CA 91125 (United States); Rhodes, J [CALTECH, Jet Prop Lab, Pasadena, CA 91109 (United States); Leauthaud, A; Kneib, J P [Lab Astrophys Marseille, F-13376 Marseille, (France); Finoguenov, A [Max Planck Inst Extraterr Phys, D-85748 Garching, (Germany); Bacon, D; Taylor, A [Inst Astron, Edinburgh EH9 3HJ, Midlothian, (United Kingdom); Aussel, H; Refregier, A [CNRS, CEA, Unite Mixte Rech, AIM, F-91191 Gif Sur Yvette, (France); Koekemoer, A; Mobasher, B [Univ Paris 07, CE Saclay, UMR 7158, F-91191 Gif Sur Yvette, (France); McCracken, H [Space Telescope Sci Inst, Baltimore, MD 21218 (United States); Pires, S; Starck, J L [Univ Paris 06, Inst Astrophys Paris, F-75014 Paris, (France); Pires, S [Ctr Etud Saclay, CEA, DSM, DAPNIA, SEDI, F-91191 Gif Sur Yvette, (France); Sasaki, S; Taniguchi, Y [Ehime Univ, Dept Phys, Matsuyama, Ehime 7908577, (Japan); Taylor, J [Univ Waterloo, Dept Phys and Astron, Waterloo, ON N2L 3G1, (Canada)

    2007-07-01

    Ordinary baryonic particles (such as protons and neutrons) account for only one-sixth of the total matter in the Universe. The remainder is a mysterious 'dark matter' component, which does not interact via electromagnetism and thus neither emits nor reflects light. As dark matter cannot be seen directly using traditional observations, very little is currently known about its properties. It does interact via gravity, and is most effectively probed through gravitational lensing: the deflection of light from distant galaxies by the gravitational attraction of foreground mass concentrations. This is a purely geometrical effect that is free of astrophysical assumptions and sensitive to all matter - whether baryonic or dark. Here we show high-fidelity maps of the large-scale distribution of dark matter, resolved in both angle and depth. We find a loose network of filaments, growing over time, which intersect in massive structures at the locations of clusters of galaxies. Our results are consistent with predictions of gravitationally induced structure formation, in which the initial, smooth distribution of dark matter collapses into filaments then into clusters, forming a gravitational scaffold into which gas can accumulate, and stars can be built. (authors)

  1. Dark matter maps reveal cosmic scaffolding

    International Nuclear Information System (INIS)

    Massey, R.; Rhodes, J.; Ellis, R.; Scoville, N.; Capak, P.; Rhodes, J.; Leauthaud, A.; Kneib, J.P.; Finoguenov, A.; Bacon, D.; Taylor, A.; Aussel, H.; Refregier, A.; Koekemoer, A.; Mobasher, B.; McCracken, H.; Pires, S.; Starck, J.L.; Pires, S.; Sasaki, S.; Taniguchi, Y.; Taylor, J.

    2007-01-01

    Ordinary baryonic particles (such as protons and neutrons) account for only one-sixth of the total matter in the Universe. The remainder is a mysterious 'dark matter' component, which does not interact via electromagnetism and thus neither emits nor reflects light. As dark matter cannot be seen directly using traditional observations, very little is currently known about its properties. It does interact via gravity, and is most effectively probed through gravitational lensing: the deflection of light from distant galaxies by the gravitational attraction of foreground mass concentrations. This is a purely geometrical effect that is free of astrophysical assumptions and sensitive to all matter - whether baryonic or dark. Here we show high-fidelity maps of the large-scale distribution of dark matter, resolved in both angle and depth. We find a loose network of filaments, growing over time, which intersect in massive structures at the locations of clusters of galaxies. Our results are consistent with predictions of gravitationally induced structure formation, in which the initial, smooth distribution of dark matter collapses into filaments then into clusters, forming a gravitational scaffold into which gas can accumulate, and stars can be built. (authors)

  2. Dark matter maps reveal cosmic scaffolding.

    Science.gov (United States)

    Massey, Richard; Rhodes, Jason; Ellis, Richard; Scoville, Nick; Leauthaud, Alexie; Finoguenov, Alexis; Capak, Peter; Bacon, David; Aussel, Hervé; Kneib, Jean-Paul; Koekemoer, Anton; McCracken, Henry; Mobasher, Bahram; Pires, Sandrine; Refregier, Alexandre; Sasaki, Shunji; Starck, Jean-Luc; Taniguchi, Yoshi; Taylor, Andy; Taylor, James

    2007-01-18

    Ordinary baryonic particles (such as protons and neutrons) account for only one-sixth of the total matter in the Universe. The remainder is a mysterious 'dark matter' component, which does not interact via electromagnetism and thus neither emits nor reflects light. As dark matter cannot be seen directly using traditional observations, very little is currently known about its properties. It does interact via gravity, and is most effectively probed through gravitational lensing: the deflection of light from distant galaxies by the gravitational attraction of foreground mass concentrations. This is a purely geometrical effect that is free of astrophysical assumptions and sensitive to all matter--whether baryonic or dark. Here we show high-fidelity maps of the large-scale distribution of dark matter, resolved in both angle and depth. We find a loose network of filaments, growing over time, which intersect in massive structures at the locations of clusters of galaxies. Our results are consistent with predictions of gravitationally induced structure formation, in which the initial, smooth distribution of dark matter collapses into filaments then into clusters, forming a gravitational scaffold into which gas can accumulate, and stars can be built.

  3. Dark matter universe

    Science.gov (United States)

    Bahcall, Neta A.

    2015-01-01

    Most of the mass in the universe is in the form of dark matter—a new type of nonbaryonic particle not yet detected in the laboratory or in other detection experiments. The evidence for the existence of dark matter through its gravitational impact is clear in astronomical observations—from the early observations of the large motions of galaxies in clusters and the motions of stars and gas in galaxies, to observations of the large-scale structure in the universe, gravitational lensing, and the cosmic microwave background. The extensive data consistently show the dominance of dark matter and quantify its amount and distribution, assuming general relativity is valid. The data inform us that the dark matter is nonbaryonic, is “cold” (i.e., moves nonrelativistically in the early universe), and interacts only weakly with matter other than by gravity. The current Lambda cold dark matter cosmology—a simple (but strange) flat cold dark matter model dominated by a cosmological constant Lambda, with only six basic parameters (including the density of matter and of baryons, the initial mass fluctuations amplitude and its scale dependence, and the age of the universe and of the first stars)—fits remarkably well all the accumulated data. However, what is the dark matter? This is one of the most fundamental open questions in cosmology and particle physics. Its existence requires an extension of our current understanding of particle physics or otherwise point to a modification of gravity on cosmological scales. The exploration and ultimate detection of dark matter are led by experiments for direct and indirect detection of this yet mysterious particle. PMID:26417091

  4. A geochemical and petrographical characterization of organic matter in the Jurassic Mikulov Marls from the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Geršlová, E.; Opletal, V.; Sýkorová, Ivana; Sedláková, I.; Geršl, M.

    141-142, MAR 1 (2015), s. 42-50 ISSN 0166-5162 Institutional support: RVO:67985891 Keywords : Mikulov Marls * kerogen type * thermal maturity Subject RIV: DB - Geology ; Mineralogy Impact factor: 3.294, year: 2015

  5. Physics of condensed matter

    CERN Document Server

    Misra, Prasanta K

    2012-01-01

    Physics of Condensed Matter is designed for a two-semester graduate course on condensed matter physics for students in physics and materials science. While the book offers fundamental ideas and topic areas of condensed matter physics, it also includes many recent topics of interest on which graduate students may choose to do further research. The text can also be used as a one-semester course for advanced undergraduate majors in physics, materials science, solid state chemistry, and electrical engineering, because it offers a breadth of topics applicable to these majors. The book be

  6. Light, Matter, and Geometry

    DEFF Research Database (Denmark)

    Frisvad, Jeppe Revall

    Interaction of light and matter produces the appearance of materials. To deal with the immense complexity of nature, light and matter is modelled at a macroscopic level in computer graphics. This work is the first to provide the link between the microscopic physical theories of light and matter...... of a material and determine the contents of the material. The book is in four parts. Part I provides the link between microscopic and macroscopic theories of light. Part II describes how to use the properties of microscopic particles to compute the macroscopic properties of materials. Part III illustrates...

  7. QED coherence in matter

    CERN Document Server

    Preparata, Giuliano

    1995-01-01

    Up until now the dominant view of condensed matter physics has been that of an "electrostatic MECCANO" (erector set, for Americans). This book is the first systematic attempt to consider the full quantum-electrodynamical interaction (QED), thus greatly enriching the possible dynamical mechanisms that operate in the construction of the wonderful variety of condensed matter systems, including life itself.A new paradigm is emerging, replacing the "electrostatic MECCANO" with an "electrodynamic NETWORK," which builds condensed matter through the long range (as opposed to the "short range" nature o

  8. Nuclear matter revisited

    International Nuclear Information System (INIS)

    Negele, J.W.; Zabolitzky, J.G.

    1978-01-01

    It is stated that at the Workshop on Nuclear and Dense Matter held at the University of Illinois in May 1977 significant progress was reported that largely resolves many of the questions raised in this journal Vol. 6, p.149, 1976. These include perturbative versus variational methods as applied to nuclear matter, exact solutions for bosons, what is known as the fermion 'homework problem', and various other considerations regarding nuclear matter, including the use of variational methods as opposed to perturbation theory. (15 references) (U.K.)

  9. Organic geochemistry investigations of crude oils from Bayoot oilfield in the Masila Basin, east Yemen and their implication for origin of organic matter and source-related type

    Directory of Open Access Journals (Sweden)

    Mohammed Hail Hakimi

    2018-03-01

    Full Text Available Thirteen crude oil samples from fractured basement reservoir rocks in the Bayoot oilfield, Masila Basin were studied to describe oil characteristics and to provide information on the source of organic matter input and the genetic link between oils and their potential source rock in the basin. The bulk geochemical results of whole oil and gasoline hydrocarbons indicate that the Bayoot oils are normal crude oil, with high hydrocarbons of more than 60%. The hydrocarbons are dominated by normal, branched and cyclic alkanes a substantial of the light aromatic compounds, suggesting aliphatic oil-prone kerogen. The high abundant of normal, branched and cyclic alkanes also indicate that the Bayoot oils are not biodegradation oils.The biomarker distributions of isoprenoid, hopane, aromatic and sterane and their cross and triangular plots suggest that the Bayoot oils are grouped into one genetic family and were generated from marine clay-rich source rock that received mixed organic matter and deposited under suboxic conditions. The biomarker distributions of the Bayoot oils are consistent with those of the Late Jurassic Madbi source rock in the basin. Biomarker maturity and oil compositions data also indicate that the Bayoot oils were generated from mature source rock with peak oil-window maturity. Keywords: Crude oil, Basement reservoir rocks, Biomarker, Organic source input, Bayoot oilfield, Masila Basin

  10. Dark matter: the astrophysical case

    International Nuclear Information System (INIS)

    Silk, J.

    2012-01-01

    The identification of dark matter is one of the most urgent problems in cosmology. I describe the astrophysical case for dark matter, from both an observational and a theoretical perspective. This overview will therefore focus on the observational motivations rather than the particle physics aspects of dark matter constraints on specific dark matter candidates. First, however, I summarize the astronomical evidence for dark matter, then I highlight the weaknesses of the standard cold dark matter model (LCDM) to provide a robust explanation of some observations. The greatest weakness in the dark matter saga is that we have not yet identified the nature of dark matter itself

  11. Matter-antimatter and matter-matter interactions at intermediate energies

    International Nuclear Information System (INIS)

    Santos, Antonio Carlos Fontes dos

    2002-01-01

    This article presents some of the recent experimental advances on the study on antimatter-matter and matter-matter interactions, and some of the subtle differences stimulated a great theoretical efforts for explanation of the results experimentally observed

  12. Little composite dark matter.

    Science.gov (United States)

    Balkin, Reuven; Perez, Gilad; Weiler, Andreas

    2018-01-01

    We examine the dark matter phenomenology of a composite electroweak singlet state. This singlet belongs to the Goldstone sector of a well-motivated extension of the Littlest Higgs with T -parity. A viable parameter space, consistent with the observed dark matter relic abundance as well as with the various collider, electroweak precision and dark matter direct detection experimental constraints is found for this scenario. T -parity implies a rich LHC phenomenology, which forms an interesting interplay between conventional natural SUSY type of signals involving third generation quarks and missing energy, from stop-like particle production and decay, and composite Higgs type of signals involving third generation quarks associated with Higgs and electroweak gauge boson, from vector-like top-partners production and decay. The composite features of the dark matter phenomenology allows the composite singlet to produce the correct relic abundance while interacting weakly with the Higgs via the usual Higgs portal coupling [Formula: see text], thus evading direct detection.

  13. Inflatable Dark Matter.

    Science.gov (United States)

    Davoudiasl, Hooman; Hooper, Dan; McDermott, Samuel D

    2016-01-22

    We describe a general scenario, dubbed "inflatable dark matter," in which the density of dark matter particles can be reduced through a short period of late-time inflation in the early Universe. The overproduction of dark matter that is predicted within many, otherwise, well-motivated models of new physics can be elegantly remedied within this context. Thermal relics that would, otherwise, be disfavored can easily be accommodated within this class of scenarios, including dark matter candidates that are very heavy or very light. Furthermore, the nonthermal abundance of grand unified theory or Planck scale axions can be brought to acceptable levels without invoking anthropic tuning of initial conditions. A period of late-time inflation could have occurred over a wide range of scales from ∼MeV to the weak scale or above, and could have been triggered by physics within a hidden sector, with small but not necessarily negligible couplings to the standard model.

  14. Dark matter search

    International Nuclear Information System (INIS)

    Bernabei, R.

    2003-01-01

    Some general arguments on the particle Dark Matter search are addressed. The WIMP direct detection technique is mainly considered and recent results obtained by exploiting the annual modulation signature are summarized. (author)

  15. Mind Over Matter: Methamphetamine

    Science.gov (United States)

    ... Teaching Guide and Series / Methamphetamine Mind Over Matter: Methamphetamine (Meth) Print Order Free Publication in: English Spanish ... paranoia, aggressiveness, and hallucinations. The Brain's Response to Methamphetamine Hi, my name's Sara Bellum. Welcome to my ...

  16. Matter Tracking Information System -

    Data.gov (United States)

    Department of Transportation — The Matter Tracking Information System (MTIS) principle function is to streamline and integrate the workload and work activity generated or addressed by our 300 plus...

  17. Prevention Research Matters

    Centers for Disease Control (CDC) Podcasts

    Prevention Research Matters is a series of one-on-one interviews with researchers from 26 university prevention research centers across the country. Their work focuses on preventing and controlling chronic diseases like obesity, cancer, and heart disease.

  18. Dynamics of interstellar matter

    International Nuclear Information System (INIS)

    Kahn, F.D.

    1975-01-01

    A review of the dynamics of interstellar matter is presented, considering the basic equations of fluid flow, plane waves, shock waves, spiral structure, thermal instabilities and early star cocoons. (B.R.H.)

  19. Dark matter search

    Energy Technology Data Exchange (ETDEWEB)

    Bernabei, R [Dipto. di Fisica, Universita di Roma ' Tor Vergata' and INFN, sez. Roma2, Rome (Italy)

    2003-08-15

    Some general arguments on the particle Dark Matter search are addressed. The WIMP direct detection technique is mainly considered and recent results obtained by exploiting the annual modulation signature are summarized. (author)

  20. Soft Active Matter

    OpenAIRE

    Marchetti, M. C.; Joanny, J. -F.; Ramaswamy, S.; Liverpool, T. B.; Prost, J.; Rao, Madan; Simha, R. Aditi

    2012-01-01

    In this review we summarize theoretical progress in the field of active matter, placing it in the context of recent experiments. Our approach offers a unified framework for the mechanical and statistical properties of living matter: biofilaments and molecular motors in vitro or in vivo, collections of motile microorganisms, animal flocks, and chemical or mechanical imitations. A major goal of the review is to integrate the several approaches proposed in the literature, from semi-microscopic t...

  1. DARK MATTER: Optical shears

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    Evidence for dark matter continues to build up. Last year (December 1993, page 4) excitement rose when the French EROS (Experience de Recherche d'Objets Sombres) and the US/Australia MACHO collaborations reported hints that small inert 'brown dwarf stars could provide some of the Universe's missing matter. In the 1930s, astronomers first began to suspect that there is a lot more to the Universe than meets the eye

  2. Charming dark matter

    Science.gov (United States)

    Jubb, Thomas; Kirk, Matthew; Lenz, Alexander

    2017-12-01

    We have considered a model of Dark Minimal Flavour Violation (DMFV), in which a triplet of dark matter particles couple to right-handed up-type quarks via a heavy colour-charged scalar mediator. By studying a large spectrum of possible constraints, and assessing the entire parameter space using a Markov Chain Monte Carlo (MCMC), we can place strong restrictions on the allowed parameter space for dark matter models of this type.

  3. Dynamics of Soft Matter

    CERN Document Server

    García Sakai, Victoria; Chen, Sow-Hsin

    2012-01-01

    Dynamics of Soft Matter: Neutron Applications provides an overview of neutron scattering techniques that measure temporal and spatial correlations simultaneously, at the microscopic and/or mesoscopic scale. These techniques offer answers to new questions arising at the interface of physics, chemistry, and biology. Knowledge of the dynamics at these levels is crucial to understanding the soft matter field, which includes colloids, polymers, membranes, biological macromolecules, foams, emulsions towards biological & biomimetic systems, and phenomena involving wetting, friction, adhesion, or micr

  4. Matter-antimatter Cosmology

    Science.gov (United States)

    Omnes, R.

    1973-01-01

    The possible existence of antimatter on a large scale in the universe is evaluated. As a starting point, an attempt was made to understand the origin of matter as being essentially analogous to the origin of backgound thermal radiation. Several theories and models are examined, with particular emphasis on nucleon-antinucleon interactions at intermediate energies. Data also cover annihilation interaction with the matter-antimatter boundary to produce the essential fluid motion known as coalesence.

  5. Matter and cosmology

    International Nuclear Information System (INIS)

    Effenberger, R.

    1974-09-01

    The author summarizes some of the many questions and answers which have been raised over the years regarding the nature of matter, the origin of its forms and the associated concept of cosmology including the formation of the universe, our place in it and its course of evolution. An examination of the development of the classical concept of matter and its subsequent transformations within the space-time fields of relativity and quantum theory is also presented

  6. Condensed Matter Nuclear Science

    Science.gov (United States)

    Biberian, Jean-Paul

    2006-02-01

    of analysis of Ti foil after glow discharge with deuterium / I. B. Savvatimova and D. V. Gavritenkov. Enhancement mechanisms of low-energy nuclear reactions / F. A. Gareev, I. E. Zhidkova, and Y. L. Ratis. Co-deposition of palladium with hydrogen isotopes / J. Dash and A. Ambadkar. Variation of the concentration of isotopes copper and zinc in human plasmas of patients affected by cancer / A. Triassi. Transmutation of metal at low energy in a confined plasma in water / D. Cirillo and V. Iorio. The conditions and realization of self-similar Coulomb collapse of condensed target and low-energy laboratory nucleosynthesis / S. V. Adamenko and V. I. Vysotskii. The spatial structure of water and the problem of controlled low-energy nuclear reactions in water matrix / V. I. Vysotskii and A. A. Kornilova. Experiments on controlled decontamination of water mixture of longlived active isotopes in biological cells / V. I. Vysotskii. Assessment of the biological effects of "strange" radiation / E. A. Pryakhin ... [et al.]. Possible nuclear transmutation of nitrogen in the earth's atmosphere / M. Fukuhara. Evidences on the occurrence of LENR-type processes in alchemical transmutations / J. Pérez-Pariente. History of the discovery of transmutation at Texas A&M University / J. O.-M. Bockris -- 4. Theory. Quantum electrodynamics. Concerning the modeling of systems in terms of quantum electro dynamics: the special case of "cold fusion" / M. Abyaneh ... [et al.]. Screening. Theoretical model of the probability of fusion between deuterons within deformed lattices with microcracks at room temperature / F. Fulvio. Resonant tunnelling. Effective interaction potential in the deuterium plasma and multiple resonance scattering / T. Toimela. Multiple scattering theory and condensed matter nuclear science - "super-absorption" in a crystal latice / X. Z. Li ... [et al.]. Ion band states. Framework for understanding LENR processes, using conventional condensed matter physics / S. R. Chubb. I

  7. Dark matter: Theoretical perspectives

    International Nuclear Information System (INIS)

    Turner, M.S.

    1993-01-01

    The author both reviews and makes the case for the current theoretical prejudice: a flat Universe whose dominant constituent is nonbaryonic dark matter, emphasizing that this is still a prejudice and not yet fact. The theoretical motivation for nonbaryonic dark matter is discussed in the context of current elementary-particle theory, stressing that (i) there are no dark-matter candidates within the open-quotes standard modelclose quotes of particle physics, (ii) there are several compelling candidates within attractive extensions of the standard model of particle physics, and (iii) the motivation for these compelling candidates comes first and foremost from particle physics. The dark-matter problem is now a pressing issue in both cosmology and particle physics, and the detection of particle dark matter would provide evidence for open-quotes new physics.close quotes The compelling candidates are a very light axion (10 -6 --10 -4 eV), a light neutrino (20--90 eV), and a heavy neutralino (10 GeV--2 TeV). The production of these particles in the early Universe and the prospects for their detection are also discussed. The author briefly mentions more exotic possibilities for the dark matter, including a nonzero cosmological constant, superheavy magnetic monopoles, and decaying neutrinos. 119 refs

  8. Dark matter: Theoretical perspectives

    International Nuclear Information System (INIS)

    Turner, M.S.

    1993-01-01

    I both review and make the case for the current theoretical prejudice: a flat Universe whose dominant constituent is nonbaryonic dark matter, emphasizing that this is still a prejudice and not yet fact. The theoretical motivation for nonbaryonic dark matter is discussed in the context of current elementary-particle theory, stressing that: (1) there are no dark matter candidates within the standard model of particle physics; (2) there are several compelling candidates within attractive extensions of the standard model of particle physics; and (3) the motivation for these compelling candidates comes first and foremost from particle physics. The dark-matter problem is now a pressing issue in both cosmology and particle physics, and the detection of particle dark matter would provide evidence for ''new physics.'' The compelling candidates are: a very light axion ( 10 -6 eV--10 -4 eV); a light neutrino (20 eV--90 eV); and a heavy neutralino (10 GeV--2 TeV). The production of these particles in the early Universe and the prospects for their detection are also discussed. I briefly mention more exotic possibilities for the dark matter, including a nonzero cosmological constant, superheavy magnetic monopoles, and decaying neutrinos

  9. Soil organic matter

    International Nuclear Information System (INIS)

    1976-01-01

    The nature, content and behaviour of the organic matter, or humus, in soil are factors of fundamental importance for soil productivity and the development of optimum conditions for growth of crops under diverse temperate, tropical and arid climatic conditions. In the recent symposium on soil organic matter studies - as in the two preceding ones in 1963 and 1969 - due consideration was given to studies involving the use of radioactive and stable isotopes. However, the latest symposium was a departure from previous efforts in that non-isotopic approaches to research on soil organic matter were included. A number of papers dealt with the behaviour and functions of organic matter and suggested improved management practices, the use of which would contribute to increasing agricultural production. Other papers discussed the turnover of plant residues, the release of plant nutrients through the biodegradation of organic compounds, the nitrogen economy and the dynamics of transformation of organic forms of nitrogen. In addition, consideration was given to studies on the biochemical transformation of organic matter, characterization of humic acids, carbon-14 dating and the development of modern techniques and their impact on soil organic matter research

  10. Dark matter: Theoretical perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Turner, M.S. (Chicago Univ., IL (United States). Enrico Fermi Inst. Fermi National Accelerator Lab., Batavia, IL (United States))

    1993-01-01

    I both review and make the case for the current theoretical prejudice: a flat Universe whose dominant constituent is nonbaryonic dark matter, emphasizing that this is still a prejudice and not yet fact. The theoretical motivation for nonbaryonic dark matter is discussed in the context of current elementary-particle theory, stressing that: (1) there are no dark