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Sample records for n-alkane film dotriacontane

  1. High-resolution ellipsometric study of an n-alkane film, dotriacontane, adsorbed on a SiO2 surface

    DEFF Research Database (Denmark)

    Volkmann, U.G.; Pino, M.; Altamirano, L.A.

    2002-01-01

    -crystal substrates. Our results suggest a model of a solid dotriacontane film that has a phase closest to the SiO2 surface in which the long-axis of the molecules is oriented parallel to the interface. Above this "parallel film" phase, a solid monolayer adsorbs in which the molecules are oriented perpendicular...... at higher coverages. In addition, we have performed high-resolution ellipsometry and stray-light measurements on dotriacontane films deposited from solution onto highly oriented pyrolytic graphite substrates. After film deposition, these substrates proved to be less stable in air than SiO2....

  2. Atomic force microscopy measurements of topography and friction on dotriacontane films adsorbed on a SiO2 surface

    DEFF Research Database (Denmark)

    Trogisch, S.; Simpson, M.J.; Taub, H.

    2005-01-01

    We report comprehensive atomic force microscopy (AFM) measurements at room temperature of the nanoscale topography and lateral friction on the surface of thin solid films of an intermediate-length normal alkane, dotriacontane (n-C32H66), adsorbed onto a SiO2 surface. Our topographic and frictional...

  3. Growth of n-alkane films on a single-crystal substrate

    DEFF Research Database (Denmark)

    Wu, Z. U.; Ehrlich, S. N.; Matthies, B.

    2001-01-01

    The structure and growth mode of alkane films (n-C/sub n/H/sub 2n+2/; n=4, 6, 7) adsorbed on a Ag(111) surface have been investigated by synchrotron X-ray scattering. New models are proposed for the butane (n=4) and hexane (n=6) monolayer and butane bilayer structures. Specular reflectivity scans...... reveal that growth of all films is preempted between two and three layers by nucleation of bulk particles oriented with a single bulk crystal plane parallel to the film. In the case of butane, the bulk particles also have a fixed azimuthal relationship with the film resulting in complete epitaxy....

  4. Thermally driven smoothening of molecular thin films: Structural transitions in n-alkane layers studied in real-time

    Energy Technology Data Exchange (ETDEWEB)

    Pithan, Linus; Weber, Christopher; Zykov, Anton; Sauer, Katrein; Opitz, Andreas; Kowarik, Stefan, E-mail: stefan.kowarik@physik.hu-berlin.de [Institut für Physik, Humboldt-Universität zu Berlin, 12489 Berlin (Germany); Meister, Eduard; Brütting, Wolfgang [Institut für Physik, Universität Augsburg, 86135 Augsburg (Germany); Jin, Chenyu; Riegler, Hans [Max-Planck-Institut für Kolloid- und Grenzflächenforschung, 14476 Potsdam-Golm (Germany)

    2015-10-28

    We use thermal annealing to improve smoothness and to increase the lateral size of crystalline islands of n-tetratetracontane (TTC, C{sub 44}H{sub 90}) films. With in situ x-ray diffraction, we find an optimum temperature range leading to improved texture and crystallinity while avoiding an irreversible phase transition that reduces crystallinity again. We employ real-time optical phase contrast microscopy with sub-nm height resolution to track the diffusion of TTC across monomolecular step edges which causes the unusual smoothing of a molecular thin film during annealing. We show that the lateral island sizes increase by more than one order of magnitude from 0.5 μm to 10 μm. This desirable behavior of 2d-Ostwald ripening and smoothing is in contrast to many other organic molecular films where annealing leads to dewetting, roughening, and a pronounced 3d morphology. We rationalize the smoothing behavior with the highly anisotropic attachment energies and low surface energies for TTC. The results are technically relevant for the use of TTC as passivation layer and as gate dielectric in organic field effect transistors.

  5. Thermodiffusion in multicomponent n-alkane mixtures.

    Science.gov (United States)

    Galliero, Guillaume; Bataller, Henri; Bazile, Jean-Patrick; Diaz, Joseph; Croccolo, Fabrizio; Hoang, Hai; Vermorel, Romain; Artola, Pierre-Arnaud; Rousseau, Bernard; Vesovic, Velisa; Bou-Ali, M Mounir; Ortiz de Zárate, José M; Xu, Shenghua; Zhang, Ke; Montel, François; Verga, Antonio; Minster, Olivier

    2017-01-01

    Compositional grading within a mixture has a strong impact on the evaluation of the pre-exploitation distribution of hydrocarbons in underground layers and sediments. Thermodiffusion, which leads to a partial diffusive separation of species in a mixture due to the geothermal gradient, is thought to play an important role in determining the distribution of species in a reservoir. However, despite recent progress, thermodiffusion is still difficult to measure and model in multicomponent mixtures. In this work, we report on experimental investigations of the thermodiffusion of multicomponent n -alkane mixtures at pressure above 30 MPa. The experiments have been conducted in space onboard the Shi Jian 10 spacecraft so as to isolate the studied phenomena from convection. For the two exploitable cells, containing a ternary liquid mixture and a condensate gas, measurements have shown that the lightest and heaviest species had a tendency to migrate, relatively to the rest of the species, to the hot and cold region, respectively. These trends have been confirmed by molecular dynamics simulations. The measured condensate gas data have been used to quantify the influence of thermodiffusion on the initial fluid distribution of an idealised one dimension reservoir. The results obtained indicate that thermodiffusion tends to noticeably counteract the influence of gravitational segregation on the vertical distribution of species, which could result in an unstable fluid column. This confirms that, in oil and gas reservoirs, the availability of thermodiffusion data for multicomponent mixtures is crucial for a correct evaluation of the initial state fluid distribution.

  6. Metabolism of Hydrocarbons in n-Alkane-Utilizing Anaerobic Bacteria.

    Science.gov (United States)

    Wilkes, Heinz; Buckel, Wolfgang; Golding, Bernard T; Rabus, Ralf

    2016-01-01

    The glycyl radical enzyme-catalyzed addition of n-alkanes to fumarate creates a C-C-bond between two concomitantly formed stereogenic carbon centers. The configurations of the two diastereoisomers of the product resulting from n-hexane activation by the n-alkane-utilizing denitrifying bacterium strain HxN1, i.e. (1-methylpentyl)succinate, were assigned as (2S,1'R) and (2R,1'R). Experiments with stereospecifically deuterated n-(2,5-2H2)hexanes revealed that exclusively the pro-S hydrogen atom is abstracted from C2 of the n-alkane by the enzyme and later transferred back to C3 of the alkylsuccinate formed. These results indicate that the alkylsuccinate-forming reaction proceeds with an inversion of configuration at the carbon atom (C2) of the n-alkane forming the new C-C-bond, and thus stereochemically resembles a SN2-type reaction. Therefore, the reaction may occur in a concerted manner, which may avoid the highly energetic hex-2-yl radical as an intermediate. The reaction is associated with a significant primary kinetic isotope effect (kH/kD ≥3) for hydrogen, indicating that the homolytic C-H-bond cleavage is involved in the first irreversible step of the reaction mechanism. The (1-methylalkyl)succinate synthases of n-alkane-utilizing anaerobic bacteria apparently have very broad substrate ranges enabling them to activate not only aliphatic but also alkyl-aromatic hydrocarbons. Thus, two denitrifiers and one sulfate reducer were shown to convert the nongrowth substrate toluene to benzylsuccinate and further to the dead-end product benzoyl-CoA. For this purpose, however, the modified β-oxidation pathway known from alkylbenzene-utilizing bacteria was not employed, but rather the pathway used for n-alkane degradation involving CoA ligation, carbon skeleton rearrangement and decarboxylation. Furthermore, various n-alkane- and alkylbenzene-utilizing denitrifiers and sulfate reducers were found to be capable of forming benzyl alcohols from diverse alkylbenzenes

  7. Variation in n-Alkane Distributions of Modern Plants: Questioning Applications of n-Alkanes in Chemotaxonomy and Paleoecology

    Science.gov (United States)

    Bush, R. T.; McInerney, F. A.

    2010-12-01

    Long chain n-alkanes (n-C21 to n-C37) are synthesized as part of the epicuticular leaf wax of terrestrial plants and are among the most recognizable and widely used plant biomarkers. n-Alkane distributions have been utilized in previous studies on modern plant chemotaxonomy, testing whether taxa can be identified based on characteristic n-alkane profiles. Dominant n-alkanes (e.g. n-C27 or n-C31) have also been ascribed to major plant groups (e.g. trees or grasses respectively) and have been used in paleoecology studies to reconstruct fluctuations in plant functional types. However, many of these studies have been based on relatively few modern plant data; with the wealth of modern n-alkane studies, a more comprehensive analysis of n-alkanes in modern plants is now possible and can inform the usefulness of n-alkane distributions as paleoecological indicators. The work presented here is a combination of measurements made using plant leaves collected from the Chicago Botanic Garden and a compilation of published literature data from six continents. We categorized plants by type: angiosperms, gymnosperms, woody plants, forbs, grasses, ferns and pteridophytes, and mosses. We then quantified n-alkane distribution parameters such as carbon preference index (CPI), average chain length (ACL), and dispersion (a measure of the spread of the profile over multiple chain lengths) and used these to compare plant groups. Among all plants, one of the emergent correlations is a decrease in dispersion with increasing CPI. Within and among plant groups, n-alkane distributions show a very large range of variation, and the results show little or no correspondence between broad plant groups and a single dominant n-alkane or a ratio of n-alkanes. These findings are true both when data from six continents are combined and when plants from a given region are compared (North America). We also compared the n-alkane distributions of woody angiosperms, woody gymnosperms, and grasses with one

  8. Solid acid catalysts in heterogeneous n-alkanes hydroisomerisation ...

    African Journals Online (AJOL)

    As the current global environmental concerns have prompted regulations to reduce the level of aromatic compounds, particularly benzene and its derivatives in gasoline, ydroisomerisation of n-alkanes is becoming a major alternative for enhancing octane number. Series of solid acid catalysts comprising of Freidel crafts, ...

  9. Theoretical study of n-alkane adsorption on metal surfaces

    DEFF Research Database (Denmark)

    Morikawa, Yoshitada; Ishii, Hisao; Seki, Kazuhiko

    2004-01-01

    The interaction between n-alkane and metal surfaces has been studied by means of density-functional theoretical calculations within a generalized gradient approximation (GGA). We demonstrate that although the GGA cannot reproduce the physisorption energy well, our calculations can reproduce the e...

  10. Flash Points of Secondary Alcohol and n-Alkane Mixtures.

    Science.gov (United States)

    Esina, Zoya N; Miroshnikov, Alexander M; Korchuganova, Margarita R

    2015-11-19

    The flash point is one of the most important characteristics used to assess the ignition hazard of mixtures of flammable liquids. To determine the flash points of mixtures of secondary alcohols with n-alkanes, it is necessary to calculate the activity coefficients. In this paper, we use a model that allows us to obtain enthalpy of fusion and enthalpy of vaporization data of the pure components to calculate the liquid-solid equilibrium (LSE) and vapor-liquid equilibrium (VLE). Enthalpy of fusion and enthalpy of vaporization data of secondary alcohols in the literature are limited; thus, the prediction of these characteristics was performed using the method of thermodynamic similarity. Additionally, the empirical models provided the critical temperatures and boiling temperatures of the secondary alcohols. The modeled melting enthalpy and enthalpy of vaporization as well as the calculated LSE and VLE flash points were determined for the secondary alcohol and n-alkane mixtures.

  11. C14–22 n-Alkanes in Soil from the Freetown Layered Intrusion, Sierra Leone: Products of Pt Catalytic Breakdown of Natural Longer Chain n-Alkanes?

    Directory of Open Access Journals (Sweden)

    John F. W. Bowles

    2018-03-01

    Full Text Available Soil above a platinum-group element (PGE-bearing horizon within the Freetown Layered Intrusion, Sierra Leone, contains anomalous concentrations of n-alkanes (CnH2n+2 in the range C14 to C22 not readily attributable to an algal or lacustrine origin. Longer chain n-alkanes (C23 to C31 in the soil were derived from the breakdown of leaf litter beneath the closed canopy humid tropical forest. Spontaneous breakdown of the longer chain n-alkanes to form C14–22 n-alkanes without biogenic or abiogenic catalysts is unlikely as the n-alkanes are stable. In the Freetown soil, the catalytic properties of the PGE (Pt in particular may lower the temperature at which oxidation of the longer chain n-alkanes can occur. Reaction between these n-alkanes and Pt species, such as Pt2+(H2O2(OH2 and Pt4+(H2O2(OH4 can bend and twist the alkanes, and significantly lower the Heat of Formation. Microbial catalysis is a possibility. Since a direct organic geochemical source of the lighter n-alkanes has not yet been identified, this paper explores the theoretical potential for abiogenic Pt species catalysis as a mechanism of breakdown of the longer n-alkanes to form C14–22 alkanes. This novel mechanism could offer additional evidence for the presence of the PGE in solution, as predicted by soil geochemistry.

  12. Distribution and sources of n-alkanes in surface sediments of Taihu Lake, China

    Directory of Open Access Journals (Sweden)

    Yu Yunlong

    2016-03-01

    Full Text Available The last study on n-alkanes in surface sediments of Taihu Lake was in 2000, only 13 surface sediment samples were analysed, in order to have a comprehensive and up-to-date understanding of n-alkanes in the surface sediments of Taihu Lake, 41 surface sediment samples were analyzed by GC-MS. C10 to C37 were detected, the total concentrations of n-alkanes ranged from 2109 ng g−1 to 9096 ng g−1 (dry weight. There was strong odd carbon predominance in long chain n-alkanes and even carbon predominance in short chain n-alkanes. When this finding was combined with the analysis results of wax n-alkanes (WaxCn, carbon preference index (CPI, unresolved complex mixture (UCM, hopanes and steranes, it was considered that the long chain n-alkanes were mainly from terrigenous higher plants, and that the short chain n-alkanes mainly originated from bacteria and algae in the lake, compared with previous studies, there were no obvious anthropogenic petrogenic inputs. Terrestrial and aquatic hydrocarbons ratio (TAR and C21−/C25+ indicated that terrigenous input was higher than aquatic sources and the nearshore n-alkanes were mainly from land-derived sources. Moreover, the distribution of short chain n-alkanes presented a relatively uniform pattern, while the long chain n-alkanes presented a trend that concentrations dropped from nearshore places to the middle of lake.

  13. Crystallisation and chain conformation of long chain n-alkanes

    International Nuclear Information System (INIS)

    Gorce, J.

    2000-06-01

    Hydrocarbon chains are a basic component in a number of systems as diverse as biological membranes, phospholipids and polymers. A better understanding of the physical properties of n-alkane chains should provide a better understanding of these more complex systems. With this aim, vibrational spectroscopy has been extensively used. This technique, sensitive to molecular details, is the only one able to both identify and quantify conformational disorder present in paraffinic systems. To achieve this, methyl deformations have been widely used as ''internal standards'' for the normalisation of peak areas. However, in the case of n-alkanes with short chain length, such as n-C 44 H 90 for example, the infrared spectra recorded at liquid nitrogen temperature and reported here show the sensitivity of these latter peaks to the various crystal structures formed. Indeed, the main frequencies of the symmetric methyl bending mode were found between 1384 cm -1 and 1368 cm -1 as a function of the crystal form. Changes in the frequency of the first order of the L.A.M. present in the Raman spectra were also observed. At higher temperatures, non all-trans conformers, inferred from different infrared bands present in the wagging mode region, were found to be essentially placed at the end of the n-alkane chains. At the monoclinic phase transition, the concentration of end-gauche conformers, proportional to the area of the infrared band at 1342 cm -1 , increases abruptly. On the contrary, in the spectra recorded at liquid nitrogen temperature no such band is observed. We also studied the degree of disorder in two purely monodisperse long chain n-alkanes, namely n-C 198 H 398 and n-C 246 H 494 . The chain conformation as well as the tilt angle of the chains from the crystal surfaces were determined by means of low frequency Raman spectroscopy and S.A.X.S. measurements on solution-crystallised samples. The increase in the number of end-gauche conformers which was expected to occur with

  14. n-Alkane adsorption to polar silica surfaces.

    Science.gov (United States)

    Brindza, Michael R; Ding, Feng; Fourkas, John T; Walker, Robert A

    2010-03-21

    The structures of medium-length n-alkane species (C(8)-C(11)) adsorbed to a hydrophilic silica/vapor interface were examined using vibrational sum frequency spectroscopy. Experiments sampling out-of-plane orientation show a clear pattern in vibrational band intensities that implies chains having primarily all-trans conformations lying flat along the interface. Further analysis shows that the methylene groups of the alkane chains have their local symmetry axes directed into and away from the surface. Spectra acquired under different polarization conditions interlock to reinforce this picture of interfacial structure and organization. Variation in signal intensities with chain length suggests that correlation between adsorbed monomers weakens with increasing chain length. This result stands in contrast with alkane behavior at neat liquid/vapor interfaces where longer length alkanes show considerably more surface induced ordering than short chain alkanes.

  15. Abundance of macroalgal organic matter in biofilms: Evidence from n-alkane biomarkers

    Digital Repository Service at National Institute of Oceanography (India)

    Garg, A; Bhosle, N.B.

    carbon (OC), organic nitrogen (ON), chlorophyll a, diatoms and bacterial numbers on the titanium panels generally increased over the period of immersion. Total lipids and n-alkane concentration also showed similar trends. n-alkanes from C sub(12) to C sub...

  16. Study of factors that influence complex-formation of n-alkanes with crystal carbamide

    Energy Technology Data Exchange (ETDEWEB)

    Dorodnova, V.S.; Korzhov, Yu.A.; Martynenko, A.G.

    1982-01-01

    Studies effect of temperature, solid phase content in the suspension and amount of MeOH on extent of n-alkane extraction during carbamide deparaffinization. A most thorough extraction of n-alkanes is achieved with a graduated temperature regimen of complex-formation.

  17. Intramolecular and Lattice Melting in n-Alkane Monolayers: An Analog of Melting in Lipid Bilayers

    DEFF Research Database (Denmark)

    Hansen, Flemming Yssing; Herwig, K.W.; Matthies, B.

    1999-01-01

    Molecular dynamics (MD) simulations and neutron diffraction experiments have been performed on n-dotriacontane (n-C32D66) monolayers adsorbed on a graphite basal-plane surface. The diffraction experiments show little change in the crystalline monolayer structure up to a temperature of similar to ...

  18. Analysis of polychlorinated n-alkanes in environmental samples.

    Science.gov (United States)

    Santos, F J; Parera, J; Galceran, M T

    2006-10-01

    Polychlorinated n-alkanes (PCAs), also known as chlorinated paraffins (CPs), are highly complex technical mixtures that contain a huge number of structural isomers, theoretically more than 10,000 diastereomers and enantiomers. As a consequence of their persistence, tendency to bioaccumulation, and widespread and unrestricted use, PCAs have been found in aquatic and terrestrial food webs, even in rural and remote areas. Recently, these compounds have been included in regulatory programs of several international organizations, including the US Environmental Protection Agency and the European Union. Consequently, there is a growing demand for reliable methods with which to analyze PCAs in environmental samples. Here, we review current trends and recent developments in the analysis of PCAs in environmental samples such as air, water, sediment, and biota. Practical aspects of sample preparation, chromatographic separation, and detection are covered, with special emphasis placed on analysis of PCAs using gas chromatography-mass spectrometry. The advantages and limitations of these techniques as well as recent improvements in quantification procedures are discussed.

  19. Application of a Crossover Equation of State to Describe Phase Equilibrium and Critical Properties of n-Alkanes and Methane/n-Alkane Mixtures

    DEFF Research Database (Denmark)

    P. C. M. Vinhal, Andre; Yan, Wei; Kontogeorgis, Georgios M.

    2018-01-01

    and the asymptotic one near the critical point. Although several crossover EOSs have been developed in the last decades their use in modeling industrial processes is rather limited. In this work, we use the crossover Soave–Redlich–Kwong (CSRK) to describe phase equilibrium and critical properties of pure n......-alkanes and methane/n-alkane binary mixtures and compare the results to two other modeling approaches of the SRK EOS. In the case of the pure fluids, CSRK gives an accurate overall description of the phase equilibrium and critical properties; nevertheless, a minor increase in the deviation of the saturation pressure...

  20. Critical wetting of n-alkanes on water; Mouillage critique des alcanes sur l`eau

    Energy Technology Data Exchange (ETDEWEB)

    Ragil, K

    1996-10-18

    This study concerns the wetting properties of n-alkanes on water under thermodynamic equilibrium conditions, a problem that is interesting for the petroleum industry as well as for the fundamental understanding of wetting phenomena. An experimental study using ellipsometry reveals that pentane on water undergoes a continuous or critical wetting transition at a temperature equal to 53.1 deg. C. This is the first experimental observation of such a transition, confirming theoretical predictions made on this subject over ten years. This transition is characterized by a continuous and reversible evolution of the thickness of the film of pentane with temperature from a thick (but finite film) to a macroscopic film. The critical wetting transition occurs when the Hamaker constant of the system, which gives the net interaction between the two interfaces bounding the wetting layer of pentane in terms of the van der Waals forces, changes sign. A theoretical approach based on the Cahn-Landau theory, which takes into account long range forces (van der Waals forces), enables us to explain the mechanism of the critical wetting transition and to show that a first-order wetting transition should precede it. Because of their similar dispersive properties, linear alkanes could all be able to show such a succession of transitions. An ellipsometry study performed on a brine/hexane/vapor system confirms that a discontinuous transition from a thin microscopic film to a thick but finite adsorbed film takes place. THis study demonstrates that the wetting of alkanes on water is determined by subtle interplay between short range and long range forces, which can lead to an intermediary state between partial and complete wetting. (author)

  1. Leaf wax n-alkane distributions in and across modern plants: Implications for paleoecology and chemotaxonomy

    Science.gov (United States)

    Bush, Rosemary T.; McInerney, Francesca A.

    2013-09-01

    Long chain (C21 to C37) n-alkanes are among the most long-lived and widely utilized terrestrial plant biomarkers. Dozens of studies have examined the range and variation of n-alkane chain-length abundances in modern plants from around the world, and n-alkane distributions have been used for a variety of purposes in paleoclimatology and paleoecology as well as chemotaxonomy. However, most of the paleoecological applications of n-alkane distributions have been based on a narrow set of modern data that cannot address intra- and inter-plant variability. Here, we present the results of a study using trees from near Chicago, IL, USA, as well as a meta-analysis of published data on modern plant n-alkane distributions. First, we test the conformity of n-alkane distributions in mature leaves across the canopy of 38 individual plants from 24 species as well as across a single growing season and find no significant differences for either canopy position or time of leaf collection. Second, we compile 2093 observations from 86 sources, including the new data here, to examine the generalities of n-alkane parameters such as carbon preference index (CPI), average chain length (ACL), and chain-length ratios for different plant groups. We show that angiosperms generally produce more n-alkanes than do gymnosperms, supporting previous observations, and furthermore that CPI values show such variation in modern plants that it is prudent to discard the use of CPI as a quantitative indicator of n-alkane degradation in sediments. We also test the hypotheses that certain n-alkane chain lengths predominate in and therefore can be representative of particular plant groups, namely, C23 and C25 in Sphagnum mosses, C27 and C29 in woody plants, and C31 in graminoids (grasses). We find that chain-length distributions are highly variable within plant groups, such that chemotaxonomic distinctions between grasses and woody plants are difficult to make based on n-alkane abundances. In contrast

  2. The effect of n-alkane selection depth on the quality of denormalizate

    Energy Technology Data Exchange (ETDEWEB)

    Dorodnova, V.S.; Bayburskaya, E.L.; Martynenko, A.G.

    1982-01-01

    The effect of n-alkane selection depth from crude diesel fuel on the quality of denormalization on a carbamide deparaffination G-64 device at the Gorknefteorgsintez Production Association. Diesel fuel with o.c. 210/sup 0/, c.c. 315/sup 0/, 828 kg/m/sup 3/ density, -25, n/sup 20/ D 1.4620, aniline point 66.9/sup 0/ and n-alkane content 14.7% was used. The regime of the stage of complex formation was maximal approximation of industrial conditions: ratio Cr: ben. 1:2.6 mass. no, complex formation 25/sup 0/, length of contact 30 min, levels of washing, 2; methanol, 2.0% in Cr. Changing the quantity of carbamide aided the various extraction depths of n-alkanes from the Cr. Following distillation of the solution the following parameters were examined: refraction, density, aniline point, diesel index; Obtained: the dependencies for changes in these indicators depending on the depth of the selection of n-alkanes from the potential or from their content in the denormalizate; as well as the dependence of the component composition of paraffins on the degree of their extraction from the Cr. To simultaneously obtain paraffins and diesel fuel of export quality with a diesel index no lower than 55, it is necessary to guarantee up to 50% (no higher) of paraffin selection from the potential Cr containing 14.7% n-alkanes; the sediment content of n-alkanes in the denormalizate must be found at the 7.4% level.

  3. Evaluation of n-alkanes and their carbon isotope enrichments (d13C) as diet composition markers

    NARCIS (Netherlands)

    Derseh, M.B.; Pellikaan, W.F.; Tolera, A.; Hendriks, W.H.

    2011-01-01

    Plant cuticular n-alkanes have been successfully used as markers to estimate diet composition and intake of grazing herbivores. However, additional markers may be required under grazing conditions in botanically diverse vegetation. This study was conducted to describe the n-alkane profiles and the

  4. Stable isotope labeled n-alkanes to assess digesta passage kinetics through the digestive tract of ruminants

    NARCIS (Netherlands)

    Warner, D.; Ferreira, L.M.M.; Breuer, M.J.H.; Dijkstra, J.; Pellikaan, W.F.

    2013-01-01

    We describe the use of carbon stable isotope (13C) labeled n-alkanes as a potential internal tracer to assess passage kinetics of ingested nutrients in ruminants. Plant cuticular n-alkanes originating from intrinsically 13C labeled ryegrass plants were pulse dosed intraruminally in four

  5. Cool-flame Extinction During N-Alkane Droplet Combustion in Microgravity

    Science.gov (United States)

    Nayagam, Vedha; Dietrich, Daniel L.; Hicks, Michael C.; Williams, Forman A.

    2014-01-01

    Recent droplet combustion experiments onboard the International Space Station (ISS) have revealed that large n-alkane droplets can continue to burn quasi-steadily following radiative extinction in a low-temperature regime, characterized by negative-temperaturecoefficient (NTC) chemistry. In this study we report experimental observations of n-heptane, n-octane, and n-decane droplets of varying initial sizes burning in oxygen/nitrogen/carbon dioxide and oxygen/helium/nitrogen environments at 1.0, 0.7, and 0.5 atmospheric pressures. The oxygen concentration in these tests varied in the range of 14% to 25% by volume. Large n-alkane droplets exhibited quasi-steady low-temperature burning and extinction following radiative extinction of the visible flame while smaller droplets burned to completion or disruptively extinguished. A vapor-cloud formed in most cases slightly prior to or following the "cool flame" extinction. Results for droplet burning rates in both the hot-flame and cool-flame regimes as well as droplet extinction diameters at the end of each stage are presented. Time histories of radiant emission from the droplet captured using broadband radiometers are also presented. Remarkably the "cool flame" extinction diameters for all the three n-alkanes follow a trend reminiscent of the ignition delay times observed in previous studies. The similarities and differences among the n-alkanes during "cool flame" combustion are discussed using simplified theoretical models of the phenomenon

  6. n-Alkane distributions as indicators of novel ecosystem development in western boreal forest soils

    Science.gov (United States)

    Norris, Charlotte; Dungait, Jennifer; Quideau, Sylvie

    2013-04-01

    Novel ecosystem development is occurring within the western boreal forest of Canada due to land reclamation following surface mining in the Athabasca Oil Sands Region. Sphagnum peat is the primary organic matter amendment used to reconstruct soils in the novel ecosystems. We hypothesised that ecosystem recovery would be indicated by an increasing similarity in the biomolecular characteristics of novel reconstructed soil organic matter (SOM) derived from peat to those of natural boreal ecosystems. In this study, we evaluated the use of the homologous series of very long chain (>C20) n-alkanes with odd-over-even predominance as biomarker signatures to monitor the re-establishment of boreal forests on reconstructed soils. The lipids were extracted from dominant vegetation inputs and SOM from a series of natural and novel ecosystem reference plots. We observed unique very long n-alkane signatures of the source vegetation, e.g. Sphagnum sp. was dominated by C31 and aspen (Populus tremuloides Michx.) leaves by C25. Greater concentrations of very long chain n-alkanes were extracted from natural than novel ecosystem SOM (puse of n-alkanes as biomarkers of ecosystem development is a promising method.

  7. Biodegradation of crude oil and n-alkanes by fungi isolated from Oman

    Energy Technology Data Exchange (ETDEWEB)

    Elshafie, Abdulkadir [Department of Biology, College of Science, Sultan Qaboos University, P.O. Box 36 Al Khod, Muscat (Oman)], E-mail: Elshafie@squ.edu.om; AlKindi, Abdulaziz Yahya [Department of Biology, College of Science, Sultan Qaboos University, P.O. Box 36 Al Khod, Muscat (Oman); Al-Busaidi, Sultan [Oman Refinery Company Laboratories, LLC, P.O. Box 3568 Ruwi PC112 (Oman); Bakheit, Charles [Department of Mathematics and Statistics, College of Science, Sultan Qaboos University, P.O. Box 36 Al Khod, Muscat (Oman); Albahry, S.N. [Department of Biology, College of Science, Sultan Qaboos University, P.O. Box 36 Al Khod, Muscat (Oman)

    2007-11-15

    Ten fungal species isolated from tar balls collected from the beaches of Oman were tested for their abilities to grow and degrade n-alkanes and crude oil. The abilities of Aspergillus niger, A. ochraceus and Penicillium chrysogenum to degrade n-alkanes (C13-C18), crude oil were compared and their mycelial biomass was measured. Significant differences were found in the utilization of C15, C16, C17 and C18 by the three fungi. Similarly, significant differences we found in the amount of biomass produced by the three fungi growing on C13, C17, C18 and crude oil. The correlation coefficient of biomass and oil utilization was not statistically significant for Aspergillus niger, significant for Aspergillus terreus and highly significant for P. chrysogenum.

  8. Application of statistical experimental methodology to optimize bioremediation of n-alkanes in aquatic environment

    International Nuclear Information System (INIS)

    Zahed, Mohammad Ali; Aziz, Hamidi Abdul; Mohajeri, Leila; Mohajeri, Soraya; Kutty, Shamsul Rahman Mohamed; Isa, Mohamed Hasnain

    2010-01-01

    Response surface methodology (RSM) was employed to optimize nitrogen and phosphorus concentrations for removal of n-alkanes from crude oil contaminated seawater samples in batch reactors. Erlenmeyer flasks were used as bioreactors; each containing 250 mL dispersed crude oil contaminated seawater, indigenous acclimatized microorganism and different amounts of nitrogen and phosphorus based on central composite design (CCD). Samples were extracted and analyzed according to US-EPA protocols using a gas chromatograph. During 28 days of bioremediation, a maximum of 95% total aliphatic hydrocarbons removal was observed. The obtained Model F-value of 267.73 and probability F < 0.0001 implied the model was significant. Numerical condition optimization via a quadratic model, predicted 98% n-alkanes removal for a 20-day laboratory bioremediation trial using nitrogen and phosphorus concentrations of 13.62 and 1.39 mg/L, respectively. In actual experiments, 95% removal was observed under these conditions.

  9. Experimental measurements and prediction of liquid densities for n-alkane mixtures

    International Nuclear Information System (INIS)

    Ramos-Estrada, Mariana; Iglesias-Silva, Gustavo A.; Hall, Kenneth R.

    2006-01-01

    We present experimental liquid densities for n-pentane, n-hexane and n-heptane and their binary mixtures from (273.15 to 363.15) K over the entire composition range (for the mixtures) at atmospheric pressure. A vibrating tube densimeter produces the experimental densities. Also, we present a generalized correlation to predict the liquid densities of n-alkanes and their mixtures. We have combined the principle of congruence with the Tait equation to obtain an equation that uses as variables: temperature, pressure and the equivalent carbon number of the mixture. Also, we present a generalized correlation for the atmospheric liquid densities of n-alkanes. The average absolute percentage deviation of this equation from the literature experimental density values is 0.26%. The Tait equation has an average percentage deviation of 0.15% from experimental density measurements

  10. Biodegradation of crude oil and n-alkanes by fungi isolated from Oman

    International Nuclear Information System (INIS)

    Elshafie, Abdulkadir; AlKindi, Abdulaziz Yahya; Al-Busaidi, Sultan; Bakheit, Charles; Albahry, S.N.

    2007-01-01

    Ten fungal species isolated from tar balls collected from the beaches of Oman were tested for their abilities to grow and degrade n-alkanes and crude oil. The abilities of Aspergillus niger, A. ochraceus and Penicillium chrysogenum to degrade n-alkanes (C13-C18), crude oil were compared and their mycelial biomass was measured. Significant differences were found in the utilization of C15, C16, C17 and C18 by the three fungi. Similarly, significant differences we found in the amount of biomass produced by the three fungi growing on C13, C17, C18 and crude oil. The correlation coefficient of biomass and oil utilization was not statistically significant for Aspergillus niger, significant for Aspergillus terreus and highly significant for P. chrysogenum

  11. Solid-Liquid equilibrium of n-alkanes using the Chain Delta Lattice Parameter model

    DEFF Research Database (Denmark)

    Coutinho, João A.P.; Andersen, Simon Ivar; Stenby, Erling Halfdan

    1996-01-01

    The formation of a solid phase in liquid mixtures with large paraffinic molecules is a phenomenon of interest in the petroleum, pharmaceutical, and biotechnological industries among onters. Efforts to model the solid-liquid equilibrium in these systems have been mainly empirical and with different...... degrees of success.An attempt to describe the equilibrium between the high temperature form of a paraffinic solid solution, commonly known as rotator phase, and the liquid phase is performed. The Chain Delta Lattice Parameter model (CDLP) is developed allowing a successful description of the solid-liquid...... equilibrium of n-alkanes ranging from n-C_20 to n-C_40.The model is further modified to achieve a more correct temperature dependence because it severely underestimates the excess enthalpy. It is shown that the ratio of excess enthalpy and entropy for n-alkane solid solutions, as happens for other solid...

  12. Mechanism of trans-vinylene groups formation in the radiolysis of polyethylene and n-alkanes

    International Nuclear Information System (INIS)

    Borzov, S.M.; Sukhov, F.F.; Slovokhotova, N.A.

    1984-01-01

    Infrared spectra of polyethylene and some n-alkanes were studied after their irradiation at 20 K with 1-MeV electrons and subsequent heating to 160 K. The mechanism of trans-vinylene groups formation is suggested, which takes into account the decay of excited states of molecules in primary processes and the intra-chain recombination of free radicals in post-irradiation reactions. (author)

  13. n-Alkane assimilation and tert-butyl alcohol (TBA) oxidation capacity in Mycobacterium austroafricanum strains.

    Science.gov (United States)

    Lopes Ferreira, Nicolas; Mathis, Hugues; Labbé, Diane; Monot, Frédéric; Greer, Charles W; Fayolle-Guichard, Françoise

    2007-06-01

    Mycobacterium austroafricanum IFP 2012, which grows on methyl tert-butyl ether (MTBE) and on tert-butyl alcohol (TBA), the main intermediate of MTBE degradation, also grows on a broad range of n-alkanes (C2 to C16). A single alkB gene copy, encoding a non-heme alkane monooxygenase, was partially amplified from the genome of this bacterium. Its expression was induced after growth on n-propane, n-hexane, n-hexadecane and on TBA but not after growth on LB. The capacity of other fast-growing mycobacteria to grow on n-alkanes (C1 to C16) and to degrade TBA after growth on n-alkanes was compared to that of M. austroafricanum IFP 2012. We studied M. austroafricanum IFP 2012 and IFP 2015 able to grow on MTBE, M. austroafricanum IFP 2173 able to grow on isooctane, Mycobacterium sp. IFP 2009 able to grow on ethyl tert-butyl ether (ETBE), M. vaccae JOB5 (M. austroaafricanum ATCC 29678) able to degrade MTBE and TBA and M. smegmatis mc2 155 with no known degradation capacity towards fuel oxygenates. The M. austroafricanum strains grew on a broad range of n-alkanes and three were able to degrade TBA after growth on propane, hexane and hexadecane. An alkB gene was partially amplified from the genome of all mycobacteria and a sequence comparison demonstrated a close relationship among the M. austroafricanum strains. This is the first report suggesting the involvement of an alkane hydroxylase in TBA oxidation, a key step during MTBE metabolism.

  14. Structural Insights into Diversity and n-Alkane Biodegradation Mechanisms of Alkane Hydroxylases

    Directory of Open Access Journals (Sweden)

    Yurui eJi

    2013-03-01

    Full Text Available Environmental microbes utilize four degradation pathways for the oxidation of n-alkanes. Although the enzymes degrading n-alkanes in different microbes may vary, enzymes functioning in the first step in the aerobic degradation of alkanes all belong to the alkane hydroxylases. Alkane hydroxylases are a class of enzymes that insert oxygen atoms derived from molecular oxygen into different sites of the alkane terminus (or termini depending on the type of enzymes. In this review, we summarize the different types of alkane hydroxylases, their degrading steps and compare typical enzymes from various classes with regard to their three dimensional structures, in order to provide insights into how the enzymes mediate their different roles in the degradation of n-alkanes and what determines their different substrate ranges. Through the above analyses, the degrading mechanisms of enzymes can be elucidated and molecular biological methods can be utilized to expand their catalytic roles in the petrochemical industry or in bioremediation of oil-contaminated environments.

  15. Investigating C4 Grass Contributions to N-alkane Based Paleoclimate Reconstructions

    Science.gov (United States)

    Doman, C. E.; Enders, S. K.; Chadwick, O.; Freeman, K. H.

    2014-12-01

    Plant wax n-alkanes are long-chain, saturated hydrocarbons contained within the protective waxy cuticle on leaves. These lipids are pervasive and persistent in soils and sediments and thus are ideal biomarkers of ancient terrestrial organic matter. In ecosystems dominated by C3 plants, the relationship between the carbon isotopic value of whole leaves and lipids is fairly well documented, but this relationship has not been fully investigated for plants that use C4 photosynthesis. In both cases, it is unclear if the isotopic relationships are sensitive to environmental conditions, or reflect inherited characteristics. This study used a natural climate gradient on the Kohala peninsula of Hawaii to investigate relationships between climate and the δ13C and δ2H values of n-alkanes in C3 and C4 plants. δ13C of C3 leaves and lipids decreased 5 ‰ from the driest to the wettest sites, consistent with published data. Carbon isotope values of C4 plants showed no relationship to moisture up to 1000 mm mean annual precipitation (MAP). Above this threshold, δ 13C values were around 10‰ more depleted, likely due to a combination of canopy effects and C4 grasses growing in an uncharacteristically wet and cold environment. In C3 plants, the fractionation between leaf and lipid carbon isotopes did not vary with MAP, which allows estimations of δ13C leaf to be made from alkanes preserved in ancient sediments. Along this transect, C3 plants produce around twice the quantity of n-alkanes as C4 grasses. C4 grasses produce longer carbon chains. As a result, n-alkanes in the geologic record will be biased towards C3 plants, but the presence of alkanes C33 and C35 indicate the contributions of C4 grasses. In both C3 and C4 plants, average chain length increased with mean annual precipitation, but the taxonomic differences in chain length were greater than environmental differences. Hydrogen isotopes of n-alkanes show no trends with MAP, but do show clear differences between plant

  16. Distribution and sources of n-alkanes and polycyclic aromatic hydrocarbons in shellfish of the Egyptian Red Sea coast

    Directory of Open Access Journals (Sweden)

    Ahmed El Nemr

    2016-06-01

    Full Text Available Aromatic hydrocarbons and n-alkanes were analyzed in shellfish collected from 13 different sites along the Egyptian Red Sea coast. All samples were analyzed for n-alkanes (C8–C40 and polycyclic aromatic hydrocarbons (EPA list of PAHs. n-Alkanes in shellfish samples from 13 locations were found to be in the range of 71.0–701.1 ng/g with a mean value of 242.2 ± 192.1 ng/g dry wt. Different indices were calculated for the n-alkanes to assess their sources. These were carbon preference index (CPI, average chain length (ACL, terrigenous/aquatic ratio (TAR, natural n-alkane ratio (NAR and proxy ratio (Paq. Most of the collected samples of n-alkanes were discovered to be from natural sources. Aromatic hydrocarbons (16 PAHs from 13 sites varied between 1.3 and 160.9 ng/g with an average of 47.9 ± 45.5 ng/g dry wt. Benzo(apyrine (BaP, a cancer risk assessment, was calculated for the PAHs and resulted in ranges between 0.08 and 4.47 with an average of 1.25 ng/g dry wt.

  17. n-Alkanes in surficial sediments of Visakhapatnam harbour, east coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Punyu, V.R.; Harji, R.R.; Bhosle, N.B.; Sawant, S.S.; Venkat, K.

    -alkanes mainly at C15, C17 and C19 Keywords. Sediments; lipids; n-alkanes; Visakhapatnam harbour. J. Earth Syst. Sci. 122, No. 2, April 2013, pp. 467–477 c© Indian Academy of Sciences 467 468 V R Punyu et al while terrestrial plants exhibit predominance of long... steel plant, a fertilizer plant and a lead and zinc smelter in the vicinity are discharged into this harbour. The harbour handles items such as man- ganese and iron ore, coal and oil products. Added to this, it receives most of the urban run...

  18. Determination of molecular diffusion coefficient in n-alkane binary mixtures: empirical correlations.

    Science.gov (United States)

    De Mezquia, D Alonso; Bou-Ali, M Mounir; Larrañaga, M; Madariaga, J A; Santamaría, C

    2012-03-08

    In this work we have measured the molecular diffusion coefficient of the n-alkane binary series nC(i)-nC(6), nC(i)-nC(10), and nC(i)-nC(12) at 298 K and 1 atm and a mass fraction of 0.5 by using the so-called sliding symmetric tubes technique. The results show that the diffusion coefficient at this concentration is proportional to the inverse viscosity of the mixture. In addition, we have also measured the diffusion coefficient of the systems nC(12)-nC(6), nC(12)-nC(7), and nC(12)-nC(8) as a function of concentration. From the data obtained, it is shown that the diffusion coefficient of the n-alkane binary mixtures at any concentration can be calculated from the molecular weight of the components and the dynamic viscosity of the corresponding mixture at 50% mass fraction.

  19. Molecular dynamics simulation studies of mid-size liquid n-Alkanes, C12–C160

    International Nuclear Information System (INIS)

    Kwon, Tae Woo; Lee, Song Hi

    2015-01-01

    In this study, we report the results of molecular dynamics simulations (MD) for model systems of mid-size liquid n-alkanes (C 12 –C 160 ) at several temperatures (⁓2700 K) in canonical ensembles to calculate structural and dynamic properties (viscosity η, self-diffusion constant D, and monomeric friction constant ζ). For the small n-alkanes for n ≤ 80, the chains are clearly ≥ 1, which leads to the conclusion that the liquid n-alkanes are far away from the Rouse regime, but for the n-alkanes for n ≥ 120, the chains are ⁓ 1 and they are Gaussian. It is found that the long chains of these n-alkanes at high temperatures show abnormalities in density, viscosity, and monomeric friction constant. The mass and temperature dependences of structural and dynamic properties (η, D, and ζ) are discussed

  20. Paleoclimatic implications of the hydrogen isotopic composition of terrigenous n-alkanes from Lake Yamzho, southern Tibetan Plateau

    International Nuclear Information System (INIS)

    Xia Zhonghuan; Xu Baiqing; Wu Guangjian; Zhu Liping; Muegler Ines; Gleixner, Gerd; Sachse, Dirk

    2009-01-01

    The hydrogen isotopic composition (δD) of leaf water used for biosynthesis of n-alkanes can be modified by climate. Therefore, the δD can be considered as potential paleolimatic proxy to explore. We compared measured δD values of alkanes (n-C 25 to n-C 31 ) extracted from a short sediment profile spanning the past 50 years with a 7-year resolution from Lake Yamzho, southern Tibetan Plateau. Climatic control was reconstructed using meteorological records of the nearby Langkazi and Lhasa weather stations. We found that the δD values of the n-alkanes correlated with the mean annular air temperature and significantly correlated with the mean growing season air temperature. On the other hand, the δD values show poor correlations with both rainfall amount and relative humidity. These results indicate that stable isotope composition of n-alkanes could be an excellent proxy for paleotemperature reconstruction. (author)

  1. n-Alkanes in sediments from the Yellow River Estuary, China: Occurrence, sources and historical sedimentary record.

    Science.gov (United States)

    Wang, Shanshan; Liu, Guijian; Yuan, Zijiao; Da, Chunnian

    2018-04-15

    A total of 21 surface sediments from the Yellow River Estuary (YRE) and a sediment core from the abandoned Old Yellow River Estuary (OYRE) were analyzed for n-alkanes using gas chromatography-mass spectrometry (GC-MS). n-Alkanes in the range C 12 -C 33 and C 13 -C 34 were identified in the surface sediments and the core, respectively. The homologous series were mainly bimodal distribution pattern without odd/even predominance in the YRE and OYRE. The total n-alkanes concentrations in the surface sediments ranged from 0.356 to 0.572mg/kg, with a mean of 0.434mg/kg on dry wt. Evaluation of n-alkanes proxies indicated that the aliphatic hydrocarbons in the surface sediments were derived mainly from a petrogenic source with a relatively low contribution of submerged/floating macrophytes, terrestrial and emergent plants. The dated core covered the time period 1925-2012 and the mean sedimentation rate was ca. 0.5cm/yr. The total n-alkanes concentrations in the core ranged from 0.0394 to 0.941mg/kg, with a mean of 0.180mg/kg. The temporal evolution of n-alkanes reflected the historical input of aliphatic hydrocarbons and was consistent with local and regional anthropogenic activity. In general, the investigation on the sediment core revealed a trend of regional environmental change and the role of anthropogenic activity in environmental change. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Viscosity and Liquid Density of Asymmetric n-Alkane Mixtures: Measurement and Modelling

    DEFF Research Database (Denmark)

    Queimada, António J.; Marrucho, Isabel M.; Coutinho, João A.P.

    2005-01-01

    Viscosity and liquid density Measurements were performed, at atmospheric pressure. in pure and mixed n-decane. n-eicosane, n-docosane, and n-tetracosane from 293.15 K (or above the melting point) up to 343.15 K. The viscosity was determined with a rolling ball viscometer and liquid densities...... with a vibrating U-tube densimeter. Pure component results agreed, oil average, with literature values within 0.2% for liquid density and 3% for viscosity. The measured data were used to evaluate the performance of two models for their predictions: the friction theory coupled with the Peng-Robinson equation...... of state and a corresponding states model recently proposed for surface tension, viscosity, vapor pressure, and liquid densities of the series of n-alkanes. Advantages and shortcoming of these models are discussed....

  3. Self-consistent molecular dynamics calculation of diffusion in higher n-alkanes.

    Science.gov (United States)

    Kondratyuk, Nikolay D; Norman, Genri E; Stegailov, Vladimir V

    2016-11-28

    Diffusion is one of the key subjects of molecular modeling and simulation studies. However, there is an unresolved lack of consistency between Einstein-Smoluchowski (E-S) and Green-Kubo (G-K) methods for diffusion coefficient calculations in systems of complex molecules. In this paper, we analyze this problem for the case of liquid n-triacontane. The non-conventional long-time tails of the velocity autocorrelation function (VACF) are found for this system. Temperature dependence of the VACF tail decay exponent is defined. The proper inclusion of the long-time tail contributions to the diffusion coefficient calculation results in the consistency between G-K and E-S methods. Having considered the major factors influencing the precision of the diffusion rate calculations in comparison with experimental data (system size effects and force field parameters), we point to hydrogen nuclear quantum effects as, presumably, the last obstacle to fully consistent n-alkane description.

  4. Measurement and modelling of hydrogen bonding in 1-alkanol plus n-alkane binary mixtures

    DEFF Research Database (Denmark)

    von Solms, Nicolas; Jensen, Lars; Kofod, Jonas L.

    2007-01-01

    Two equations of state (simplified PC-SAFT and CPA) are used to predict the monomer fraction of 1-alkanols in binary mixtures with n-alkanes. It is found that the choice of parameters and association schemes significantly affects the ability of a model to predict hydrogen bonding in mixtures, eve...... studies, which is clarified in the present work. New hydrogen bonding data based on infrared spectroscopy are reported for seven binary mixtures of alcohols and alkanes. (C) 2007 Elsevier B.V. All rights reserved....... though pure-component liquid densities and vapour pressures are predicted equally accurately for the associating compound. As was the case in the study of pure components, there exists some confusion in the literature about the correct interpretation and comparison of experimental data and theoretical...

  5. Catalytic dehydroaromatization of n-alkanes by pincer-ligated iridium complexes

    Science.gov (United States)

    Ahuja, Ritu; Punji, Benudhar; Findlater, Michael; Supplee, Carolyn; Schinski, William; Brookhart, Maurice; Goldman, Alan S.

    2011-02-01

    Aromatic hydrocarbons are among the most important building blocks in the chemical industry. Benzene, toluene and xylenes are obtained from the high temperature thermolysis of alkanes. Higher alkylaromatics are generally derived from arene-olefin coupling, which gives branched products—that is, secondary alkyl arenes—with olefins higher than ethylene. The dehydrogenation of acyclic alkanes to give alkylaromatics can be achieved using heterogeneous catalysts at high temperatures, but with low yields and low selectivity. We present here the first catalytic conversion of n-alkanes to alkylaromatics using homogeneous or molecular catalysts—specifically ‘pincer’-ligated iridium complexes—and olefinic hydrogen acceptors. For example, the reaction of n-octane affords up to 86% yield of aromatic product, primarily o-xylene and secondarily ethylbenzene. In the case of n-decane and n-dodecane, the resulting alkylarenes are exclusively unbranched (that is, n-alkyl-substituted), with selectivity for the corresponding o-(n-alkyl)toluene.

  6. Biodegradation of n-alkanes on oil-seawater interfaces at different temperatures and microbial communities associated with the degradation.

    Science.gov (United States)

    Lofthus, Synnøve; Netzer, Roman; Lewin, Anna S; Heggeset, Tonje M B; Haugen, Tone; Brakstad, Odd Gunnar

    2018-04-01

    Oil biodegradation studies have mainly focused on microbial processes in dispersions, not specifically on the interfaces between the oil and the seawater in the dispersions. In this study, a hydrophobic adsorbent system, consisting of Fluortex fabrics, was used to investigate biodegradation of n-alkanes and microbial communities on oil-seawater interfaces in natural non-amended seawater. The study was performed over a temperature range from 0 to 20 °C, to determine how temperature affected biodegradation at the oil-seawater interfaces. Biodegradation of n-alkanes were influenced both by seawater temperature and chain-length. Biotransformation rates of n-alkanes decreased by reduced seawater temperature. Low rate coefficients at a seawater temperature of 0 °C were probably associated with changes in physical-chemical properties of alkanes. The primary bacterial colonization of the interfaces was predominated by the family Oceanospirillaceae at all temperatures, demonstrating the wide temperature range of these hydrocarbonoclastic bacteria. The mesophilic genus Oleibacter was predominant at the seawater temperature of 20 °C, and the psychrophilic genus Oleispira at 5 and 0 °C. Upon completion of n-alkane biotransformation, other oil-degrading and heterotrophic bacteria became abundant, including Piscirickettsiaceae (Cycloclasticus), Colwelliaceae (Colwellia), Altermonadaceae (Altermonas), and Rhodobacteraceae. This is one of a few studies that describe the biodegradation of oil, and the microbial communities associated with the degradation, directly at the oil-seawater interfaces over a large temperature interval.

  7. Predictive Local Composition Models for Solid/Liquid Equilibrium in n-Alkane Systems: Wilson Equation for Multicomponent Systems

    DEFF Research Database (Denmark)

    Coutinho, João A.P.; Stenby, Erling Halfdan

    1996-01-01

    The predictive local composition model is applied to multicomponent hydrocarbon systems with long-chain n-alkanes as solutes. The results show that it can successfully be extended to highorder systems and accurately predict the solid appearance temperature, also known as cloud point, in solutions...

  8. A nonequilibrium simulation method for calculating tracer diffusion coefficients of small solutes in n-alkane liquids and polymers

    NARCIS (Netherlands)

    van der Vegt, N.F.A.; Briels, Willem J.; Wessling, Matthias; Strathmann, H.

    1998-01-01

    The tracer diffusion coefficients of methane in n-alkane liquids of increasing chain length were calculated by measuring the friction from short time nonequilibrium molecular dynamics simulations. The frictional constant was calculated from the exponentially decaying distance between two methane

  9. Carbon isotope analysis of n-alkanes in dust from the lower atmosphere over the eastern Atlantic

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Schefuß, E.; Ratmeyer, V.; Stuut, J-B.W.; Jansen, J.H.F.

    2003-01-01

    Atmospheric dust samples collected along a transect off the West African coast have been investigated for their lipid content and compound-specific stable carbon isotope compositions. The saturated hydrocarbon fractions of the organic solvent extracts consist mainly of long-chain n-alkanes derived

  10. 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

  11. Degradability of n-alkanes during ex situ natural bioremediation of soil contaminated by heavy residual fuel oil (mazut

    Directory of Open Access Journals (Sweden)

    Ali Ramadan Mohamed Muftah

    2013-01-01

    Full Text Available It is well known that during biodegradation of oil in natural geological conditions, or oil pollutants in the environment, a degradation of hydrocarbons occurs according to the well defined sequence. For example, the major changes during the degradation process of n-alkanes occur in the second, slight and third, moderate level (on the biodegradation scale from 1 to 10. According to previous research, in the fourth, heavy level, when intensive changes of phenanthrene and its methyl isomers begin, n-alkanes have already been completely removed. In this paper, the ex situ natural bioremediation (unstimulated bioremediation, without addition of biomass, nutrient substances and biosurfactant of soil contaminated with heavy residual fuel oil (mazut was conducted during the period of 6 months. Low abundance of n-alkanes in the fraction of total saturated hydrocarbons in the initial sample (identification was possible only after concentration by urea adduction technique showed that the investigated oil pollutant was at the boundary between the third and the fourth biodegradation level. During the experiment, an intense degradation of phenanthrene and its methyl-, dimethyl-and trimethyl-isomers was not followed by the removal of the remaining n-alkanes. The abundance of n-alkanes remained at the initial low level, even at end of the experiment when the pollutant reached one of the highest biodegradation levels. These results showed that the unstimulated biodegradation of some hydrocarbons, despite of their high biodegradability, do not proceed completely to the end, even at final degradation stages. In the condition of the reduced availability of some hydrocarbons, microorganisms tend to opt for less biodegradable but more accessible hydrocarbons.

  12. Structure and phase transitions of monolayers of intermediate-length n-alkanes on graphite studied by neutron diffraction and molecular dynamics simulation

    Science.gov (United States)

    Diama, A.; Matthies, B.; Herwig, K. W.; Hansen, F. Y.; Criswell, L.; Mo, H.; Bai, M.; Taub, H.

    2009-08-01

    We present evidence from neutron diffraction measurements and molecular dynamics (MD) simulations of three different monolayer phases of the intermediate-length alkanes tetracosane (n-C24H50 denoted as C24) and dotriacontane (n-C32H66 denoted as C32) adsorbed on a graphite basal-plane surface. Our measurements indicate that the two monolayer films differ principally in the transition temperatures between phases. At the lowest temperatures, both C24 and C32 form a crystalline monolayer phase with a rectangular-centered (RC) structure. The two sublattices of the RC structure each consists of parallel rows of molecules in their all-trans conformation aligned with their long axis parallel to the surface and forming so-called lamellas of width approximately equal to the all-trans length of the molecule. The RC structure is uniaxially commensurate with the graphite surface in its [110] direction such that the distance between molecular rows in a lamella is 4.26 Å=√3 ag, where ag=2.46 Å is the lattice constant of the graphite basal plane. Molecules in adjacent rows of a lamella alternate in orientation between the carbon skeletal plane being parallel and perpendicular to the graphite surface. Upon heating, the crystalline monolayers transform to a "smectic" phase in which the inter-row spacing within a lamella expands by ˜10% and the molecules are predominantly oriented with the carbon skeletal plane parallel to the graphite surface. In the smectic phase, the MD simulations show evidence of broadening of the lamella boundaries as a result of molecules diffusing parallel to their long axis. At still higher temperatures, they indicate that the introduction of gauche defects into the alkane chains drives a melting transition to a monolayer fluid phase as reported previously.

  13. Variation in the Apparent Biosynthetic Fractionation for N-alkane δD Among Terrestrial Plants: Patterns, Mechanisms, and Implications

    Science.gov (United States)

    Johnson, J. E.; Tipple, B. J.; Betancourt, J. L.; Ehleringer, J. R.; Leavitt, S. W.; Monson, R. K.

    2016-12-01

    Long-chain normal alkanes (n-alkanes) are a component of the leaf cuticle of all terrestrial plants. Since the hydrogen in the n-alkanes is derived from the hydrogen in plants' water sources and is non-exchangeable, the stable hydrogen isotopic composition (δD) of the n-alkanes provides information about the δD of environmental waters. While this relationship creates opportunities for using n-alkane δD for process-based reconstructions of δD of environmental waters, progress in this direction is currently constrained by the observation that terrestrial plants exhibit a startlingly wide range of apparent biosynthetic fractionations. To understand the mechanisms responsible for variation in the apparent biosynthetic fractionations, we compared measurements and models of δD for n-C29 in a water-limited ecosystem where the timing of primary and secondary cuticle deposition is closely coupled to water availability (Tumamoc Hill, Tucson, Arizona, USA). During the 2014-2015 hydrologic year, the most widespread and abundant plant species at this site exhibited δD for n-C29 varying over a total range of 102‰. Discrete samples of leaf water collected at the same time as the n-C29 samples exhibited δD varying over a total range of only 53‰, but a continuous model of leaf water through the annual cycle predicted δD varying over a total range of 190‰. These results indicate that the observed variation in the apparent biosynthetic fractionation for n-C29 δD could be primarily attributable to leaf water dynamics that are temporally uncoupled from primary and secondary cuticle deposition. If a single biosynthetic fractionation does describe the relationship between the δD of n-alkanes and leaf water during intervals of cuticle deposition, it will facilitate process-based interpretations of n-alkane δD values in ecological, hydrological, and climatological studies of modern and ancient terrestrial environments.

  14. Molecular dynamics insight to phase transition in n-alkanes with carbon nanofillers

    Directory of Open Access Journals (Sweden)

    Monisha Rastogi

    2015-05-01

    Full Text Available The present work aims to investigate the phase transition, dispersion and diffusion behavior of nanocomposites of carbon nanotube (CNT and straight chain alkanes. These materials are potential candidates for organic phase change materials(PCMs and have attracted flurry of research recently. Accurate experimental evaluation of the mass, thermal and transport properties of such composites is both difficult as well as economically taxing. Additionally it is crucial to understand the factors that results in modification or enhancement of their characteristic at atomic or molecular level. Classical molecular dynamics approach has been extended to elucidate the same. Bulk atomistic models have been generated and subjected to rigorous multistage equilibration. To reaffirm the approach, both canonical and constant-temperature, constant- pressure ensembles were employed to simulate the models under consideration. Explicit determination of kinetic, potential, non-bond and total energy assisted in understanding the enhanced thermal and transport property of the nanocomposites from molecular point of view. Crucial parameters including mean square displacement and simulated self diffusion coefficient precisely define the balance of the thermodynamic and hydrodynamic interactions. Radial distribution function also reflected the density variation, strength and mobility of the nanocomposites. It is expected that CNT functionalization could improve the dispersion within n-alkane matrix. This would further ameliorate the mass and thermal properties of the composite. Additionally, the determined density was in good agreement with experimental data. Thus, molecular dynamics can be utilized as a high throughput technique for theoretical investigation of nanocomposites PCMs.

  15. Molecular dynamics insight to phase transition in n-alkanes with carbon nanofillers

    Energy Technology Data Exchange (ETDEWEB)

    Rastogi, Monisha [School of Engineering, Indian Institute of Technology Mandi, Himachal Pradesh 175 001 (India); Vaish, Rahul, E-mail: rahul@iitmandi.ac.in [School of Engineering, Indian Institute of Technology Mandi, Himachal Pradesh 175 001 (India); Materials Research Centre, Indian Institute of Science, Bangalore 560 012 (India)

    2015-05-15

    The present work aims to investigate the phase transition, dispersion and diffusion behavior of nanocomposites of carbon nanotube (CNT) and straight chain alkanes. These materials are potential candidates for organic phase change materials(PCMs) and have attracted flurry of research recently. Accurate experimental evaluation of the mass, thermal and transport properties of such composites is both difficult as well as economically taxing. Additionally it is crucial to understand the factors that results in modification or enhancement of their characteristic at atomic or molecular level. Classical molecular dynamics approach has been extended to elucidate the same. Bulk atomistic models have been generated and subjected to rigorous multistage equilibration. To reaffirm the approach, both canonical and constant-temperature, constant- pressure ensembles were employed to simulate the models under consideration. Explicit determination of kinetic, potential, non-bond and total energy assisted in understanding the enhanced thermal and transport property of the nanocomposites from molecular point of view. Crucial parameters including mean square displacement and simulated self diffusion coefficient precisely define the balance of the thermodynamic and hydrodynamic interactions. Radial distribution function also reflected the density variation, strength and mobility of the nanocomposites. It is expected that CNT functionalization could improve the dispersion within n-alkane matrix. This would further ameliorate the mass and thermal properties of the composite. Additionally, the determined density was in good agreement with experimental data. Thus, molecular dynamics can be utilized as a high throughput technique for theoretical investigation of nanocomposites PCMs.

  16. The structure of n-alkane binary mixtures adsorbed on graphite

    International Nuclear Information System (INIS)

    Espeau, Philippe; White, John W.; Papoular, Robert J.

    2005-01-01

    The thermodynamics and structure of the surface adsorbed phase in binary C15-C16 and C15-C17 n-alkane mixtures confined in graphite pores have been studied by differential scanning calorimetry and small-angle X-ray scattering. The previously observed selective adsorption of the longer alkane for chain length differences greater than five carbon atoms is verified but reduced for chain length differences less than or equal to two. With a difference in chain length of one carbon atom, Vegard's law is followed for the melting points of the adsorbed mixture and the (0 2) d-spacing is a continuous function of the mole fraction x. With a two-carbon atom difference, samples aged for 1 week have a lamellar structure for which the entities A 1-x B x try to be commensurate with the substrate. The same samples aged for 1 month show a continuous parabolic x-dependence for both the melting points and the d-spacings. An explanation in terms of selective probability of adsorption is proposed based on crystallographic considerations

  17. The structure of n-alkane binary mixtures adsorbed on graphite

    Energy Technology Data Exchange (ETDEWEB)

    Espeau, Philippe [Laboratoire de Chimie Physique et Minerale, Faculte de Pharmacie, Universite Rene Descartes-Paris V, F-75006 Paris (France)]. E-mail: philippe.espeau@univ-paris5.fr; White, John W. [Research School of Chemistry, Australian National University, Canberra, ACT 0200 (Australia); Papoular, Robert J. [Laboratoire Leon Brillouin, CEA-CEN Saclay, F-91191 Gif-sur-Yvette Cedex (France)

    2005-12-15

    The thermodynamics and structure of the surface adsorbed phase in binary C15-C16 and C15-C17 n-alkane mixtures confined in graphite pores have been studied by differential scanning calorimetry and small-angle X-ray scattering. The previously observed selective adsorption of the longer alkane for chain length differences greater than five carbon atoms is verified but reduced for chain length differences less than or equal to two. With a difference in chain length of one carbon atom, Vegard's law is followed for the melting points of the adsorbed mixture and the (0 2) d-spacing is a continuous function of the mole fraction x. With a two-carbon atom difference, samples aged for 1 week have a lamellar structure for which the entities A{sub 1-x}B {sub x} try to be commensurate with the substrate. The same samples aged for 1 month show a continuous parabolic x-dependence for both the melting points and the d-spacings. An explanation in terms of selective probability of adsorption is proposed based on crystallographic considerations.

  18. Modeling SOA formation from the oxidation of intermediate volatility n-alkanes

    Directory of Open Access Journals (Sweden)

    J. Lee-Taylor

    2012-08-01

    Full Text Available The chemical mechanism leading to SOA formation and ageing is expected to be a multigenerational process, i.e. a successive formation of organic compounds with higher oxidation degree and lower vapor pressure. This process is here investigated with the explicit oxidation model GECKO-A (Generator of Explicit Chemistry and Kinetics of Organics in the Atmosphere. Gas phase oxidation schemes are generated for the C8–C24 series of n-alkanes. Simulations are conducted to explore the time evolution of organic compounds and the behavior of secondary organic aerosol (SOA formation for various preexisting organic aerosol concentration (COA. As expected, simulation results show that (i SOA yield increases with the carbon chain length of the parent hydrocarbon, (ii SOA yield decreases with decreasing COA, (iii SOA production rates increase with increasing COA and (iv the number of oxidation steps (i.e. generations needed to describe SOA formation and evolution grows when COA decreases. The simulated oxidative trajectories are examined in a two dimensional space defined by the mean carbon oxidation state and the volatility. Most SOA contributors are not oxidized enough to be categorized as highly oxygenated organic aerosols (OOA but reduced enough to be categorized as hydrocarbon like organic aerosols (HOA, suggesting that OOA may underestimate SOA. Results show that the model is unable to produce highly oxygenated aerosols (OOA with large yields. The limitations of the model are discussed.

  19. Plant n-alkane production from litterfall altered the diversity and community structure of alkane degrading bacteria in litter layer in lowland subtropical rainforest in Taiwan

    Science.gov (United States)

    Huang, Tung-Yi; Hsu, Bing-Mu; Chao, Wei-Chun; Fan, Cheng-Wei

    2018-03-01

    n-Alkane and alkane-degrading bacteria have long been used as crucial biological indicators of paleoecology, petroleum pollution, and oil and gas prospecting. However, the relationship between n-alkane and alkane-degrading bacteria in natural forests is still poorly understood. In this study, long-chain n-alkane (C14-C35) concentrations in litterfall, litter layer, and topsoil as well as the diversity and abundance of n-alkane-degrading bacterial communities in litter layers were investigated in three habitats across a lowland subtropical rainforest in southern Taiwan: ravine, windward, and leeward habitats in Nanjenshan. Our results demonstrate that the litterfall yield and productivity of long-chain n-alkane were highest in the ravine habitats. However, long-chain n-alkane concentrations in all habitats were decreased drastically to a similar low level from the litterfall to the bulk soil, suggesting a higher rate of long-chain n-alkane degradation in the ravine habitat. Operational taxonomic unit (OTU) analysis using next-generation sequencing data revealed that the relative abundances of microbial communities in the windward and leeward habitats were similar and different from that in the ravine habitat. Data mining of community amplicon sequencing using the NCBI database revealed that alkB-gene-associated bacteria (95 % DNA sequence similarity to alkB-containing bacteria) were most abundant in the ravine habitat. Empirical testing of litter layer samples using semi-quantitative polymerase chain reaction for determining alkB gene levels confirmed that the ravine habitat had higher alkB gene levels than the windward and leeward habitats. Heat map analysis revealed parallels in pattern color between the plant and microbial species compositions of the habitats, suggesting a causal relationship between the plant n-alkane production and microbial community diversity. This finding indicates that the diversity and relative abundance of microbial communities in the

  20. Contamination profiles of short-chain polychlorinated n-alkanes in foodstuff samples from Japan

    Energy Technology Data Exchange (ETDEWEB)

    Matsukami, Hidenori; Kurunthachalam, S; Ohi, Etsumasa; Takasuga, Takumi [Shimadzu Techno Research, Inc., Kyoto (Japan); Iino, Fukuya; Nakanishi, Junko [National Inst. of Advanced Industrial Science and Technology, Tsukuba (Japan)

    2004-09-15

    Polychlorinated n-alkanes (PCAs) are group of chemicals manufactured by chlorination of liquid n-paraffin or paraffin wax that contain 30 to 70% chlorine by weight. Large amounts of PCAs are widely used as plasticizers for vinyl chloride, lubricants, paints, and flame retardants and number of other industrial applications. Annual global production of PCAs is approximately 300 kilo tones, with a majority having medium-carbon-chain (C14-C19) length. According to the investigation made by Kagaku Kogyo Nippon-Sha, the annual consumption of PCAs in Japan was about 83,000 tons in between 1986-2001. Short-carbon-chain (C10-C13) has been placed on the Priority Substance List under Canadian Environmental Protection Act and on the Environmental Protection Agency Toxic Release Inventory in the USA due to its potential to act as tumor promoters in mammals. Data on environment levels of PCAs is meager, nevertheless, PCAs have been measured at relatively high concentrations in biota from Sweden, biota, sediment from Canada and marine biota and human milk from the Canadian Arctic. In our earlier study, we reported concentrations of short-chain PCAs from sewage treatment plant (STP) collected from Tama River, Tokyo and river water and sediment from Tokyo and Osaka. STP influent water contained greater shortchain PCAs concentrations than STP effluent. In addition, some river water and sediment samples contained detectable concentrations of short-chain PCAs, which was similar to other industrial countries. However, there is no study conducted to explore the contamination profiles of short-chain PCAs in human foodstuff samples. In the present study, we analyzed eleven foodstuff samples that were purchased from various supermarkets in order to know the short-chain PCAs concentrations in the foodstuff and possible human total daily intake (TDI) amounts.

  1. Flow reactor studies of non-equilibrium plasma-assisted oxidation of n-alkanes.

    Science.gov (United States)

    Tsolas, Nicholas; Lee, Jong Guen; Yetter, Richard A

    2015-08-13

    The oxidation of n-alkanes (C1-C7) has been studied with and without the effects of a nanosecond, non-equilibrium plasma discharge at 1 atm pressure from 420 to 1250 K. Experiments have been performed under nearly isothermal conditions in a flow reactor, where reactive mixtures are diluted in Ar to minimize temperature changes from chemical reactions. Sample extraction performed at the exit of the reactor captures product and intermediate species and stores them in a multi-position valve for subsequent identification and quantification using gas chromatography. By fixing the flow rate in the reactor and varying the temperature, reactivity maps for the oxidation of fuels are achieved. Considering all the fuels studied, fuel consumption under the effects of the plasma is shown to have been enhanced significantly, particularly for the low-temperature regime (T<800 K). In fact, multiple transitions in the rates of fuel consumption are observed depending on fuel with the emergence of a negative-temperature-coefficient regime. For all fuels, the temperature for the transition into the high-temperature chemistry is lowered as a consequence of the plasma being able to increase the rate of fuel consumption. Using a phenomenological interpretation of the intermediate species formed, it can be shown that the active particles produced from the plasma enhance alkyl radical formation at all temperatures and enable low-temperature chain branching for fuels C3 and greater. The significance of this result demonstrates that the plasma provides an opportunity for low-temperature chain branching to occur at reduced pressures, which is typically observed at elevated pressures in thermal induced systems. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  2. Hopane, sterane and n-alkane distributions in shallow sediments hosting high arsenic groundwaters in Cambodia

    International Nuclear Information System (INIS)

    Dongen, Bart E. van; Rowland, Helen A.L.; Gault, Andrew G.; Polya, David A.; Bryant, Charlotte; Pancost, Richard D.

    2008-01-01

    The presence of elevated As in ground waters exploited for drinking water and irrigation in South-East Asia is causing serious impacts on human health. A key mechanism that causes the mobilization of As in these waters is microbially mediated reductive transformation of As-bearing Fe(III) hydrated oxides and the role of degradable organic matter (OM) in this process is widely recognized. A number of different types of OM that drive As release in these aquifers have been suggested, including petroleum derived hydrocarbons naturally seeping into shallow sediments from deeper thermally mature source rocks. However, the amount of information on the characteristics of the OM in South-East Asian aquifers is limited. Here the organic geochemical analyses of the saturated hydrocarbon fractions and radiocarbon analysis, of two additional sites in SE Asia are reported. The results show that the OM in a given sedimentary horizon likely derives from multiple sources including naturally occurring petroleum. The importance of naturally occurring petroleum as one of the sources was clearly indicated by the n-alkane CPI of approximately 1, the presence of an unresolved complex mixture, and hopane (dominated by 17α(H),21β(H) hopanes) and sterane distribution patterns. The results also indicate that the OM in these aquifers varies tremendously in content, character and potential bioavailability. Furthermore, the presence of petroleum derived OM in sediments at both sites doubles the number of locations where their presence has been observed in association with As-rich, shallow aquifers, suggesting that the role of petroleum derived OM in microbially mediated As release might occur over a wider range of geographical locations than previously thought

  3. Molecular sieve isolation technique for use in stable carbon isotope analysis of individual long-chain n-alkanes in crude oil

    International Nuclear Information System (INIS)

    Yamada, Keita; Kon, Makoto; Naraoka, Hiroshi; Ishiwatari, Ryoshi; Uzaki, Minoru.

    1994-01-01

    An isolation procedure of microgram amounts of long-chain n-alkanes from crude oil using molecular sieve was examined for its applicability to stable carbon isotope analysis by gas chromatography/isotope ratio mass spectrometry (GC/IRMS). The procedure examined is as follows: molecular sieve (type 5A, 200 mg) in 1 ml of isooctane solvent are mixed with a saturated hydrocarbon fraction extracted from an appropriate amount (approx. 20 mg) of crude oil and stayed at room temperatures for more than 3 hours. Long-chain n-alkanes are isolated by extraction with n-hexane after dissolution of the resulting molecular sieve with 47% hydrofluoric acid solution. The recoveries were 90±6% for C 15 -C 34 n-alkanes when their total amounts applied do not exceed 1.4 mg. No effect of the isolation procedure on carbon isotope ratios of n-alkanes was observed. (author)

  4. Paleoclimate and Asian monsoon variability inferred from n-alkanes and their stable isotopes at lake Donggi Cona, NE Tibetan Plateau

    Science.gov (United States)

    Saini, Jeetendra; Guenther, Franziska; Mäusbacher, Roland; Gleixner, Gerd

    2015-04-01

    The Tibetan Plateau is one of the most extensive and sensitive region of elevated topography affecting global climate. The interplay between the Asian summer monsoon and the westerlies greatly influences the lake systems at the Tibetan Plateau. Despite a considerable number of research efforts in last decade, possible environmental reactions to change in monsoon dynamics are still not well understood. Here we present results from a sediment core of lake Donggi Cona, which dates back to late glacial period. Distinct organic geochemical proxies and stable isotopes are used to study the paleoenvironmental and hydrological changes in late glacial and Holocene period. Sedimentary n-alkanes of lake Donggi Cona are used as a proxy for paleoclimatic and monsoonal reconstruction. The hydrogen (δD) and carbon (δ13C) isotopes of n-alkanes are used as proxy for hydrological and phytoplankton productivity, respectively . Qualitative and quantitative analysis were performed for n-alkanes over the sediment core. δD proxy for sedimentary n-alkanes is used to infer lake water and rainfall signal. δD of (n-alkane C23) records the signal of the lake water, whereas δD of (n-alkane C29) record the precipitation signal, hence act as an appropriate proxy to track Asian monsoon. Long chain n-alkanes dominate over the sediment core while unsaturated mid chain n-alkenes have high abundance in some samples. From 18.4-13.8 cal ka BP, sample shows low organic productivity due to cold and arid climate. After 13.8-11.8 cal ka BP, slight increase in phytoplankton productivity indicate onset of weaker monsoon. From 11.8-6.8 cal ka BP, high content of organic matter indicates rise in productivity and strong monsoon with high inflow. After 6.8 cal ka BP, decrease in phytoplankton productivity indicating cooler climate and show terrestrial signal. Our results provide new insight into the variability of east Asian monsoon and changes in phytoplankton productivity for last 18.4 ka. Keywords: n-alkanes

  5. Stable hydrogen isotopic composition of n-alkanes in atmospheric aerosols as a tracer for the source region of terrestrial plant waxes

    Science.gov (United States)

    Yamamoto, S.; Kawamura, K.

    2009-12-01

    Studies on molecular composition and compound-specific carbon isotopic ratio (δ13C) of leaf wax n-alkanes in atmospheric aerosols have revealed a long-range atmospheric transport of terrestrial higher plant materials over the south Atlantic and western Pacific oceans. However, molecular and δ13C compositions of terrestrial plant waxes in the eastern part of the Asian continent are relatively constant reflecting C3-dominated vegetation, which makes it difficult to specify the source regions of plant materials in the atmospheric aerosols over the East Asia and northwest Pacific regions. Recent observation displays a large (>100‰) spatial variation in hydrogen isotopic composition (δD) of rainwater in East Asia. Because δD values of terrestrial higher plants sensitively reflect those of precipitation waters, δD of leaf waxes are expected to provide information on their source region. In this study, we measured the δD of n-alkanes in atmospheric aerosols from Tokyo to better understand the origin of leaf wax n-alkanes in atmospheric aerosols. The δD values of fossil fuel n-alkanes (C21 to C24) in Tokyo aerosols range from -65 to -94‰, which are in a range of those reported in marine crude oils. In contrast, the δD of higher molecular weight (C29 and C31) n-alkanes (δDHMW) show much larger values by ~70‰ than those of fossil fuel n-alkanes. Their values were found to exhibit concomitant variations with carbon preference index (CPI), suggesting that the δDHMW reflect the δD of leaf wax n-alkanes with a variable contribution from fossil fuel n-alkanes. Nevertheless, good positive correlation (r = 0.89, p < 0.01) between the δDHMW and CPI values enable us to remove the contribution of fossil fuels using a mass balance approach by assuming that CPI of fossil fuel is 1 and CPI of plant waxes is 5-15. Calculated n-alkane δD values averaged from -170 to -185‰ for C29 and from -155 to -168‰ for C31. These values are consistent with those reported from

  6. Preferential methanogenic biodegradation of short-chain n-alkanes by microbial communities from two different oil sands tailings ponds.

    Science.gov (United States)

    Mohamad Shahimin, Mohd Faidz; Foght, Julia M; Siddique, Tariq

    2016-05-15

    Oil sands tailings ponds harbor diverse anaerobic microbial communities capable of methanogenic biodegradation of solvent hydrocarbons entrained in the tailings. Mature fine tailings (MFT) from two operators (Albian and CNRL) that use different extraction solvents were incubated with mixtures of either two (n-pentane and n-hexane) or four (n-pentane, n-hexane, n-octane and n-decane) n-alkanes under methanogenic conditions for ~600 d. Microbes in Albian MFT began methane production by ~80 d, achieving complete depletion of n-pentane and n-hexane in the two-alkane mixture and their preferential biodegradation in the four-alkane mixture. Microbes in CNRL MFT preferentially metabolized n-octane and n-decane in the four-alkane mixture after a ~80 d lag but exhibited a lag of ~360 d before commencing biodegradation of n-pentane and n-hexane in the two-alkane mixture. 16S rRNA gene pyrosequencing revealed Peptococcaceae members as key bacterial n-alkane degraders in all treatments except CNRL MFT amended with the four-alkane mixture, in which Anaerolineaceae, Desulfobacteraceae (Desulfobacterium) and Syntrophaceae (Smithella) dominated during n-octane and n-decane biodegradation. Anaerolineaceae sequences increased only in cultures amended with the four-alkane mixture and only during n-octane and n-decane biodegradation. The dominant methanogens were acetoclastic Methanosaetaceae. These results highlight preferential n-alkane biodegradation by microbes in oil sands tailings from different producers, with implications for tailings management and reclamation. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Size distributions of n-alkanes, fatty acids and fatty alcohols in springtime aerosols from New Delhi, India.

    Science.gov (United States)

    Kang, Mingjie; Fu, Pingqing; Aggarwal, Shankar G; Kumar, Sudhanshu; Zhao, Ye; Sun, Yele; Wang, Zifa

    2016-12-01

    Size-segregated aerosol samples were collected in New Delhi, India from March 6 to April 6, 2012. Homologous series of n-alkanes (C 19 C 33 ), n-fatty acids (C 12 C 30 ) and n-alcohols (C 16 C 32 ) were measured using gas chromatography/mass spectrometry. Results showed a high-variation in the concentrations and size distributions of these chemicals during non-haze, haze, and dust storm days. In general, n-alkanes, n-fatty acids and n-alcohols presented a bimodal distribution, peaking at 0.7-1.1 μm and 4.7-5.8 μm for fine modes and coarse modes, respectively. Overall, the particulate matter mainly existed in the coarse mode (≥2.1 μm), accounting for 64.8-68.5% of total aerosol mass. During the haze period, large-scale biomass burning emitted substantial fine hydrophilic smoke particles into the atmosphere, which leads to relatively larger GMDs (geometric mean diameter) of n-alkanes in the fine mode than those during the dust storms and non-haze periods. Additionally, the springtime dust storms transported a large quantity of coarse particles from surrounding or local areas into the atmosphere, enhancing organic aerosol concentration and inducing a remarkable size shift towards the coarse mode, which are consistent with the larger GMDs of most organic compounds especially in total and coarse modes. Our results suggest that fossil fuel combustion (e.g., vehicular and industrial exhaust), biomass burning, residential cooking, and microbial activities could be the major sources of lipid compounds in the urban atmosphere in New Delhi. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Kinetics and mechanistic study of n-alkane hydroisomerization reaction on Pt-doped γ-alumina catalyst

    Directory of Open Access Journals (Sweden)

    Abhishek Dhar

    2017-12-01

    Full Text Available The catalysts γ-alumina (GA, the reference catalyst and Pt doped γ-alumina (PGA-s were synthesized using a simple sol-gel technique, in which at first preparation of porous base (GA, then impregnation of platinum salt over the base and finally reduction of platinum in the surface of the support were done. These catalysts prepared in different mole ratios of Pt:Al as 2:1, 1:1 and 1:2 are named as PGA-1, PGA-2 and PGA-3 respectively. The isomerization of n-alkanes (n-hexane, n-heptane and n-octane were investigated over the synthesized catalysts. The 2-methyl pentane (2-MP, 2,2-dimethyl pentane (2,2-DMP and 2,3-dimethyl hexane (2,3-DMH are the major products of respective isomerization of n-hexane, n-heptane and n-octane, besides a small amount of other branched isomers are also produced. The product distribution is comparable to that reported for Pt based other catalysts. The optimal mole ratios of Pt:Al is 1:1 (PGA-2 gives quite good catalytic activity for isomerization of n-alkane. Even through in reusability study, PGA-2 gives better performance than others. We have mainly focused on kinetic study, reaction mechanism behind isomerization and calculated the order of reactions and activation energies of the isomerization reactions in the present work. Keywords: Isomerization, n-alkanes, Catalyst, Reaction mechanism, Kinetics study, Activation energy

  9. Re-evaluating the isotopic divide between angiosperms and gymnosperms using n-alkane δ13C values

    Science.gov (United States)

    Bush, R. T.; McInerney, F. A.

    2009-12-01

    Angiosperm δ13C values are typically 1-3‰ more negative than those of co-occurring gymnosperms. This is known for both bulk leaf and compound-specific values from n-alkanes, which are stable, straight-chain hydrocarbons (C23-C35) found in the epicuticular leaf wax of vascular plants. For n-alkanes, there is a second distinction between the δ13C values of angiosperms and gymnosperms—δ13C values generally decrease with increasing chain-length in angiosperms, while in gymnosperms they increase. These two distinctions have been used to support the ‘plant community change hypothesis’ explaining the difference between the terrestrial and marine carbon isotope excursions during the Paleocene-Eocene Thermal Maximum (PETM.) Preserved n-alkanes from terrestrial paleosols in the Bighorn Basin, Wyoming reveal a negative carbon isotope excursion during the PETM of 4-5‰, which is 1-2‰ greater than the excursion recorded by marine carbonates. The local plant community, known from macrofossils as well as palynoflora, shifted from a deciduous, mixed angiosperm/gymnosperm flora to a suite of evergreen angiosperm species during the PETM. At the end of the PETM, the community returned to a mixed deciduous flora very similar to the original. This change in the plant community could thus magnify the terrestrial negative carbon isotope excursion to the degree necessary to explain its divergence from the marine record. However, the comparison between modern angiosperms and gymnosperms has been made mostly between broadleaf, deciduous angiosperms and evergreen, coniferous gymnosperms. New data analyzing deciduous, coniferous gymnosperms, including Metasequoia glyptostroboides and Taxodium distichum, suggests that the division previously ascribed to taxonomy may actually be based on leaf habit and physiology, specifically broadleaf, deciduous versus needle-leaf, evergreen plants. If differences in n-alkane δ13C values can be described not as angiosperms versus gymnosperms

  10. Acidic ionic liquids for n-alkane isomerization in a liquid-liquid or slurry-phase reaction mode

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, C.; Hager, V.; Geburtig, D.; Kohr, C.; Wasserscheid, P. [Erlangen-Nuernberg Univ. (Germany). Lehrstuhl fuer Chemische Reaktionstechnik; Haumann, M. [Chemical Reaction Engineering, FAU Busan Campus, Korea (Korea, Republic of)

    2011-07-01

    Highly acidic ionic liquid (IL) catalysts offer the opportunity to convert n-alkanes at very low reaction temperatures. The results of IL catalyzed isomerization and cracking reactions of pure n-octane are presented. Influence of IL composition, [C{sub 4}C{sub 1}Im]Cl / AlCl{sub 3} / H{sub 2}SO{sub 4} and [C{sub 4}C{sub 1}Im]Cl / AlCl{sub 3} / 1-chlorooctane, on catalyst activity and selectivities to branched alkanes was investigated. Acidic chloroaluminate IL catalysts form liquid-liquid biphasic systems with unpolar organic product mixtures. Thus, recycling of the acidic IL is enabled by simple phase separation in the liquid-liquid biphasic reaction mode or the IL can be immobilized on an inorganic support with a large specific surface area. These supported ionic liquid phase (SILP) catalysts offer the advantage to get a macroscopically heterogeneous system while still preserving all benefits of the homogeneous catalyst which can be used for the slurry-phase n-alkane isomerization. The interaction of the solid support and acidic IL influences strongly the catalytic activity. (orig.)

  11. Anomaly in the Chain Length Dependence of n-Alkane Diffusion in ZIF-4 Metal-Organic Frameworks

    Directory of Open Access Journals (Sweden)

    Seungtaik Hwang

    2018-03-01

    Full Text Available Molecular diffusion is commonly found to slow down with increasing molecular size. Deviations from this pattern occur in some host materials with pore sizes approaching the diameters of the guest molecules. A variety of theoretical models have been suggested to explain deviations from this pattern, but robust experimental data are scarcely available. Here, we present such data, obtained by monitoring the chain length dependence of the uptake of n-alkanes in the zeolitic imidazolate framework ZIF-4. A monotonic decrease in diffusivity from ethane to n-butane was observed, followed by an increase for n-pentane, and another decrease for n-hexane. This observation was confirmed by uptake measurements with n-butane/n-pentane mixtures, which yield faster uptake of n-pentane. Further evidence is provided by the observation of overshooting effects, i.e., by transient n-pentane concentrations exceeding the (eventually attained equilibrium value. Accompanying grand canonical Monte Carlo simulations reveal, for the larger n-alkanes, significant differences between the adsorbed and gas phase molecular configurations, indicating strong confinement effects within ZIF-4, which, with increasing chain length, may be expected to give rise to configurational shifts facilitating molecular propagation at particular chain lengths.

  12. Third O2 addition reactions promote the low-temperature auto-ignition of n-alkanes

    KAUST Repository

    Wang, Zhandong

    2016-01-20

    Comprehensive low-temperature oxidation mechanisms are needed to accurately predict fuel auto-ignition properties. This paper studies the effects of a previously unconsidered third O2 addition reaction scheme on the simulated auto-ignition of n-alkanes. We demonstrate that this extended low-temperature oxidation scheme has a minor effect on the simulation of n-pentane ignition; however, its addition significantly improves the prediction of n-hexane auto-ignition under low-temperature rapid compression machine conditions. Additional simulations of n-hexane in a homogeneous charge compression ignition engine show that engine-operating parameters (e.g., intake temperature and combustion phasing) are significantly altered when the third O2 addition kinetic mechanism is considered. The advanced combustion phasing is initiated by the formation and destruction of additional radical chain-branching intermediates produced in the third O2 addition process, e.g. keto-dihydroperoxides and/or keto-hydroperoxy cyclic ethers. Our results indicate that third O2 addition reactions accelerate low-temperature radical chain branching at conditions of relevance to advance engine technologies, and therefore these chemical pathways should also be considered for n-alkanes with 6 or more carbon atoms. © 2015 The Combustion Institute.

  13. Anomaly in the Chain Length Dependence of n-Alkane Diffusion in ZIF-4 Metal-Organic Frameworks.

    Science.gov (United States)

    Hwang, Seungtaik; Gopalan, Arun; Hovestadt, Maximilian; Piepenbreier, Frank; Chmelik, Christian; Hartmann, Martin; Snurr, Randall Q; Kärger, Jörg

    2018-03-15

    Molecular diffusion is commonly found to slow down with increasing molecular size. Deviations from this pattern occur in some host materials with pore sizes approaching the diameters of the guest molecules. A variety of theoretical models have been suggested to explain deviations from this pattern, but robust experimental data are scarcely available. Here, we present such data, obtained by monitoring the chain length dependence of the uptake of n- alkanes in the zeolitic imidazolate framework ZIF-4. A monotonic decrease in diffusivity from ethane to n- butane was observed, followed by an increase for n- pentane, and another decrease for n- hexane. This observation was confirmed by uptake measurements with n- butane/ n -pentane mixtures, which yield faster uptake of n- pentane. Further evidence is provided by the observation of overshooting effects, i.e., by transient n- pentane concentrations exceeding the (eventually attained) equilibrium value. Accompanying grand canonical Monte Carlo simulations reveal, for the larger n- alkanes, significant differences between the adsorbed and gas phase molecular configurations, indicating strong confinement effects within ZIF-4, which, with increasing chain length, may be expected to give rise to configurational shifts facilitating molecular propagation at particular chain lengths.

  14. Changes in the n-alkane composition of avocado pulp oil ( Persea americana, Mill. during fruit ripening

    Directory of Open Access Journals (Sweden)

    Giuffrè, A. M.

    2005-03-01

    Full Text Available The n-alkane composition of Avocado pulp oil (cv. Hass was investigated during fruit ripening. Three samples of fruit were harvested on March 3, 2003, March 18, 2003 and April 2, 2003. Glass gravity column chromatography was employed to separate n-alkanes from other minor components contained in the unsaponifiable fraction. Gas chromatography was used to analyze the eluate. Fourteen compounds were detected ranging from n -C21 to n -C34; mainly n -C24, followed by n -C25 and then by n -C23. Quantities of n -C21, n -C22, n -C23, n -C27 and n -C28 progressively increased during ripening, whereas n -C24, n -C25, n -C26, n -C29, n -C30 and n -C34 decreased from the first harvest date to the third harvest date. While odd-numbered carbon n-alkanes increased (52.38 %, 52.85 % and 53.06 % for the three samples respectively, even-numbered carbon n-alkanes decreased as the fruit ripened (47.62 %, 47.15 % and 46.94 %. The total n-alkane content decreased during ripening, from 25.20 mg/Kg (first harvest date to 16.77 mg/Kg (third harvest date. In order to minimize.Se ha analizado la composición en hidrocarburos lineales saturados del aceite de la pulpa de aguacate (variedad Hass. Tres muestras fueron recolectadas: el 3 de marzo 2003, el 18 de marzo 2003 y el 2 de abril 2003. La separación de los hidrocarburos lineales saturados se realizó mediante fraccionamiento del insaponificable por cromatografía gravimétrica de adsorción en columna y la determinación de los mismos hidrocarburos por cromatografía gaseosa. 14 compuestos fueron detectados del n- C21 al n- C34. El n- C24 fue el mayoritario, seguido del n- C25 y el n- C23. El porcentaje de n- C21, n- C22, n- C23, n- C27 y n- C28, aumentó durante la maduración, mientras que el porcentaje de n- C24, n- C25, n- C26, n- C29, n- C30 y C34 disminuyó desde el 3 de marzo 2003 hasta el 2 de abril 2003. Los hidrocarburos lineales saturados con número impar de átomos de carbono aumentaron (52.38 %, 52

  15. Terrestrial environmental changes around the Gulf of Aden over the last 210 kyr deduced from the sediment n-alkane record: Implications for the dispersal of Homo sapiens

    Science.gov (United States)

    Isaji, Yuta; Kawahata, Hodaka; Ohkouchi, Naohiko; Murayama, Masafumi; Tamaki, Kensaku

    2015-03-01

    We analyzed long-chain (C25-C36) n-alkanes and pollen grains in sediments from the Gulf of Aden covering the last 212 kyr to reconstruct the surrounding terrestrial environment, a critical region for the dispersal of Homo sapiens. Substantial increases in the flux of n-alkanes during 200-185, 120-95, and 70-50 ka were interpreted to indicate enhanced vegetation biomass in the Arabian Peninsula and the northern part of the Horn of Africa or increase in lithogenic material inputs. Periods of enhanced n-alkane flux occurred during or immediately after pluvial episodes, indicating that the increased precipitation may have induced substantially enhanced vegetation biomass, creating favorable conditions for Homo sapiens. Additionally, vegetation may have increased due to moderate precipitation unrecorded by speleothems or in accordance with the lowering of sea level, indicating that the dispersal might have been possible even after the shift to an arid environment indicated by the speleothems.

  16. Anaerobic Coculture of Microalgae with Thermosipho globiformans and Methanocaldococcus jannaschii at 68°C Enhances Generation of n-Alkane-Rich Biofuels after Pyrolysis

    Science.gov (United States)

    Matsuyama, Shigeru; Igarashi, Kensuke; Utsumi, Motoo; Shiraiwa, Yoshihiro; Kuwabara, Tomohiko

    2013-01-01

    We tested different alga-bacterium-archaeon consortia to investigate the production of oil-like mixtures, expecting that n-alkane-rich biofuels might be synthesized after pyrolysis. Thermosipho globiformans and Methanocaldococcus jannaschii were cocultured at 68°C with microalgae for 9 days under two anaerobic conditions, followed by pyrolysis at 300°C for 4 days. Arthrospira platensis (Cyanobacteria), Dunaliella tertiolecta (Chlorophyta), Emiliania huxleyi (Haptophyta), and Euglena gracilis (Euglenophyta) served as microalgal raw materials. D. tertiolecta, E. huxleyi, and E. gracilis cocultured with the bacterium and archaeon inhibited their growth and CH4 production. E. huxleyi had the strongest inhibitory effect. Biofuel generation was enhanced by reducing impurities containing alkanenitriles during pyrolysis. The composition and amounts of n-alkanes produced by pyrolysis were closely related to the lipid contents and composition of the microalgae. Pyrolysis of A. platensis and D. tertiolecta containing mainly phospholipids and glycolipids generated short-carbon-chain n-alkanes (n-tridecane to n-nonadecane) and considerable amounts of isoprenoids. E. gracilis also produced mainly short n-alkanes. In contrast, E. huxleyi containing long-chain (31 and 33 carbon atoms) alkenes and very long-chain (37 to 39 carbon atoms) alkenones, in addition to phospholipids and glycolipids, generated a high yield of n-alkanes of various lengths (n-tridecane to n-pentatriacontane). The gas chromatography-mass spectrometry (GC-MS) profiles of these n-alkanes were similar to those of native petroleum crude oils despite containing a considerable amount of n-hentriacontane. The ratio of phytane to n-octadecane was also similar to that of native crude oils. PMID:23183975

  17. Seasonal variation of the particle size distribution of n-alkanes and polycyclic aromatic hydrocarbons (PAHs) in urban aerosol of Guangzhou, China.

    Science.gov (United States)

    Tang, X L; Bi, X H; Sheng, G Y; Tan, J H; Fu, J M

    2006-06-01

    Seasonal aerosol samples have been collected by Andersen Hi-Vol pumping system equipped with a five stage cascade impactor and a backup filter (size range: 10-7.2 microm, 7.2-3.0 microm, 3.0-1.5 microm, 1.5-0.95 microm, 0.95-0.49 microm, gas chromatography and PAHs were measured using gas chromatography/mass spectrometry analysis. The bimodal log-normal distributions of n-alkanes and semi-volatile PAHs were found, while for non-volatile PAHs that was unimodal, so much as the mode of semi-volatile PAHs was similar with that of the particles. The n-alkanes and PAHs were preferably associated with fine particles. C (max) (carbon number maximum) (C(22)-C(26)), CPI (carbon preference index) (1.12-1.21), U/R (unresolved to resolved components ratio) (7.42-10.7), wax% (0.9-3.12%) and the diagnostic ratios for PAHs revealed that vehicular emission was the major source of these organic compounds during the study periods, while the contribution of epicuticular waxes emitted by terrestrial plants was minor. CPI(2) (values for petrogenic hydrocarbons), CPI(3) (values for biogenic n-alkanes) and wax% revealed that the natural preferentially accumulated in the larger aerosol while the anthropogenic in the smaller. In addition, the different MMDs (mass median diameters) for n-alkanes and PAHs were observed in different seasons. The MMDs for n-alkanes and PAHs were higher in autumn/winter than those in spring/summer. The seasonal effect was related to the hydrocarbon content in the individual particulate fractions, showing a preferential association of n-alkanes and PAHs with larger particles in the autumn/winter season.

  18. Source apportionment of PAHs and n-alkanes bound to PM1 collected near the Venice highway.

    Science.gov (United States)

    Valotto, Gabrio; Rampazzo, Giancarlo; Gonella, Francesco; Formenton, Gianni; Ficotto, Silvia; Giraldo, Giorgia

    2017-04-01

    n-Alkanes and polycyclic aromatic hydrocarbons (PAHs) bound to atmospheric particulate matter (PM 1 ) were investigated in a traffic site located in an urban area of Venice Province (Eastern Po Valley, Italy) during the cold season. Considering the critical situation affecting the Veneto Region concerning the atmospheric pollution and the general lack of information on PM 1 composition and emission in this area, this experimental study aims at determining the source profile, their relative contributions and the dispersion of finer particles. Four sources were identified and quantified using the Positive Matrix Factorization receptor model: (1) mixed combustions related to the residential activities, (2) agricultural biomass burning in addition to the resuspension of anthropogenic and natural debris carried by the wind, (3) gasoline and (4) diesel traffic-related combustions. The role of local atmospheric circulation was also investigated to identify the pollutant sources. Copyright © 2016. Published by Elsevier B.V.

  19. Oh Magadi! Interpreting isoGDGTs and n-alkanes in a saline tropical lake: Lake Magadi, Kenya

    Science.gov (United States)

    Ferland, T. M.; Werne, J. P.; Castañeda, I. S.; Cohen, A. S.; Lowenstein, T. K.; Deocampo, D.; Renaut, R.; Bernhart, O. R.

    2017-12-01

    The Hominin Sites and Paleolakes Drilling Project (HSPDP) seeks to understand the paleoclimatic and paleoenvironmental context of hominin adaptation and evolution by analysis of paleolacustrine cores taken near key hominin fossil and artifact localities in Kenya and Ethiopia. We present biomarker and compound specific isotope data from a 200 m drill core from Lake Magadi, Kenya. Located 20 km from the Koora Plain in the southern Kenya Rift, and adjacent to the Olorgesailie basin, Lake Magadi is in one of the richest Early-Late Pleistocene archaeological localities in Africa, a region that has been key in debates about the relationship between climate and evolution. Present-day Lake Magadi is a saline pan, a descendant of a series of paleolakes that have occupied its drainage basin and progressively dried for approximately one million years. Nearly 70% of samples analyzed for n-alkanes recorded a robust terrestrial signal. The majority of samples did not contain the complete suite of branched GDGTs necessary to reconstruct temperature from the Methylation of Branched Tetraethers and Cyclisation of Branched Tetraethers (MBT/CBT; Weijers et al., 2007) proxy. The TetraEther indeX with 86 carbon atoms (TEX86; Schouten et al., 2002) temperature proxy was established for 90% of samples analyzed for isoGDGTs, however the Methane and Ring Indices (Zhang et al., 2011; Zhang et al., 2016) suggest that the TEX86 is not applicable to temperature reconstruction at Magadi. Despite this, the Magadi TEX86 temperature reconstruction appears to agree with not only the trends in our n-alkane data but with other regional and global records, including the GRIP-2 δ18O record. We compare our temperature data to other records in the region, and investigate influences on our TEX86 data including microbial community turnover and lake drying.

  20. The effect of environmental factors on stable isotopic composition of n-alkanes in Mediterranean olive oils

    Science.gov (United States)

    Pedentchouk, Nikolai; Mihailova, Alina; Abbado, Dimitri

    2014-05-01

    Traceability of the geographic origin of olive oils is an important issue from both commercial and health perspectives. This study evaluates the impact of environmental factors on stable C and H isotope compositions of n-alkanes in extra virgin olive oils from Croatia, France, Greece, Italy, Morocco, Portugal, Slovenia, and Spain. The data are used to investigate the applicability of stable isotope methodology for olive oil regional classification in the Mediterranean region. Analysis of stable C isotope composition of n-C29 alkane showed that extra virgin olive oils from Portugal and Spain have the most positive n-C29 alkane delta13C values. Conversely, olive oils from Slovenia, northern and central Italy are characterized by the most negative values. Overall, the n-C29 alkane delta13C values show a positive correlation with the mean air temperature during August-December and a negative correlation with the mean relative humidity during these months. Analysis of stable H isotope composition of n-C29 alkane revealed that the deltaD values are the most positive in olive oils from Greece and Morocco and the most negative in oils from northern Italy. The deltaD values of oils show significant correlation with all the analyses geographical parameters: the mean air temperature and relative humidity during August-December, the total amount of rainfall (the same months) and the annual deltaD values of precipitation. As predictor variables in the Categorical Data Analysis, the n-C29 alkane deltaD values show the most significant discriminative power, followed by the n-C29 alkane delta13C values. Overall, 93.4% of olive oil samples have been classified correctly into one of the production regions. Our findings suggest that an integrated analysis of C and H isotope compositions of n-alkanes extracted from extra virgin olive oil could become a useful tool for geographical provenancing of this highly popular food commodity.

  1. Difference equation model for isothermal gas chromatography expresses retention behavior of homologues of n-alkanes excluding the influence of holdup time

    Science.gov (United States)

    Wu, Liejun; Chen, Yongli; Caccamise, Sarah A.L.; Li, Qing X.

    2012-01-01

    A difference equation (DE) model is developed using the methylene retention increment (Δtz) of n-alkanes to avoid the influence of gas holdup time (tM). The effects of the equation orders (1st–5th) on the accuracy of a curve fitting show that a linear equation (LE) is less satisfactory and it is not necessary to use a complicated cubic or higher order equation. The relationship between the logarithm of Δtz and the carbon number (z) of the n-alkanes under isothermal conditions closely follows the quadratic equation for C3–C30 n-alkanes at column temperatures of 24–260 °C. The first and second order forward differences of the expression (Δlog Δtz and Δ2log Δtz, respectively) are linear and constant, respectively, which validates the DE model. This DE model lays a necessary foundation for further developing a retention model to accurately describe the relationship between the adjusted retention time and z of n-alkanes. PMID:22939376

  2. Distribution and origins of n-alkanes, hopanes, and steranes in rivers and marine sediments from Southwest Caspian coast, Iran: implications for identifying petroleum hydrocarbon inputs.

    Science.gov (United States)

    Shirneshan, Golshan; Bakhtiari, Alireza Riyahi; Memariani, Mahmoud

    2016-09-01

    The occurrence of n-alkanes and biomarkers (hopane and sterane) in surface sediments from Southwestern coasts of Caspian Sea and 28 rivers arriving to this lake, determined with a gas chromatography-mass spectrometry method, was used to assess the impacts of anthropogenic activities in the studied area. The concentrations of total n-alkanes (Σ21 n-alkane) in costal and riverine sediments varied from 249.2 to 3899.5 and 56 to 1622.4 μg g(-1), respectively. An evaluation of the source diagnostic indices indicated that petroleum related sources (petrogenic) were mainly contributed to n-alkanes in costal and most riverine sediments. Only the hydrocarbons in sediment of 3 rivers were found to be mainly of biogenic origin. Principal component analysis using hopane diagnostic ratios in costal and riverine sediments, and Anzali, Turkmenistan, and Azerbaijan oils were used to identify the sources of hydrocarbons in sediments. It was indicated that the anthropogenic contributions in most of the costal sediment samples are dominated with inputs of oil spills from Turkmenistan and Azerbaijan countries.

  3. Heat capacity and Joule-Thomson coefficient of selected n-alkanes at 0.1 and 10 MPa in broad temperature ranges

    DEFF Research Database (Denmark)

    Regueira Muñiz, Teresa; Varzandeh, Farhad; Stenby, Erling Halfdan

    2017-01-01

    Isobaric heat capacity of six n-alkanes, i.e. n-hexane, n-octane, n-decane, n-dodecane, n-tetradecane and n-hexadecane, was determined with a Calvet type differential heat-flux calorimeter at 0.1 and 10 MPa in a broad temperature range. The measured isobaric heat capacity data were combined...

  4. Nucleation, growth and habit modification of n-alkanes and homologous mixtures in the absence and presence of flow improving additives

    International Nuclear Information System (INIS)

    Taggart, Audrey M.

    1996-01-01

    A detailed study has been performed on the nucleation, growth and habit modification of n-alkanes and homologous mixtures in the absence and presence of flow improving additives in an attempt to gain a clearer appreciation of the interaction mechanisms behind wax / additive crystallisation. Kinetic and structural assessment of melt phase n-alkanes illustrate the different crystallographic forms present within the homologous series. Studies demonstrate the alternating behaviour of the even and odd numbered homologues which converges as a function of increasing molecular weight. Greater crystal lattice stabilities were found for those n-alkanes which have an even carbon number and which crystallise into the triclinic crystal structure. Solid state phase behaviour of the n-alkanes was found to vary depending on the number and parity of n. Nucleation kinetic studies of n-alkanes and homologous mixtures from model diesel fuel solvents (dodecane, m-xylene, decalin, pristane and a dewaxed fuel) are assessed using turbidity as the method of crystallite detection. Saturation temperatures are found to be related to both alkane structure and molecular chain length for all solvent systems. N-alkane solubilities are lower for n-alkane like solvents. The width of the meta stable zone varies as a function of solvent in order of dodecane ≅ pristane 19 H 40 and solvent m-xylene. Wax precipitation from distillate fuels in the presence of flow improving additives (di-alkyl di-amino xylene, phthalic acid and sulphobenzene acid derivatives and high molecular weight polymers) reveal responsive wax crystal nucleator and growth inhibitor additives. The crystal morphology of heptacosane, C 27 H 56 to simulate a model wax crystal is assessed in addition to its response to blocker 'tailor made' additives: methyl substituted C 27 H 56 and di-alkyl substituted phenyl additives [additive (A) and (B)]. Pure C 27 H 56 reveals a thin lozenge shaped platelet. All additives studied induce growth

  5. Transport properties of mixtures by the soft-SAFT + free-volume theory: application to mixtures of n-alkanes and hydrofluorocarbons.

    Science.gov (United States)

    Llovell, F; Marcos, R M; Vega, L F

    2013-05-02

    In a previous paper (Llovell et al. J. Phys. Chem. B, submitted for publication), the free-volume theory (FVT) was coupled with the soft-SAFT equation of state for the first time to extend the capabilities of the equation to the calculation of transport properties. The equation was tested with molecular simulations and applied to the family of n-alkanes. The capability of the soft-SAFT + FVT treatment is extended here to other chemical families and mixtures. The compositional rules of Wilke (Wilke, C. R. J. Chem. Phys. 1950, 18, 517-519) are used for the diluted term of the viscosity, while the dense term is evaluated using very simple mixing rules to calculate the viscosity parameters. The theory is then used to predict the vapor-liquid equilibrium and the viscosity of mixtures of nonassociating and associating compounds. The approach is applied to determine the viscosity of a selected group of hydrofluorocarbons, in a similar manner as previously done for n-alkanes. The soft-SAFT molecular parameters are taken from a previous work, fitted to vapor-liquid equilibria experimental data. The application of FVT requires three additional parameters related to the viscosity of the pure fluid. Using a transferable approach, the α parameter is taken from the equivalent n-alkane, while the remaining two parameters B and Lv are fitted to viscosity data of the pure fluid at several isobars. The effect of these parameters is then investigated and compared to those obtained for n-alkanes, in order to better understand their effect on the calculations. Once the pure fluids are well characterized, the vapor-liquid equilibrium and the viscosity of nonassociating and associating mixtures, including n-alkane + n-alkane, hydrofluorocarbon + hydrofluorocarbon, and n-alkane + hydrofluorocarbon mixtures, are calculated. One or two binary parameters are used to account for deviations in the vapor-liquid equilibrium diagram for nonideal mixtures; these parameters are used in a

  6. Deposition of radiation energy in solids as visualized by the distribution, structure and properties of alkyl radicals in γ-irradiated n-alkane single crystals

    International Nuclear Information System (INIS)

    Gillbro, T.; Lund, A.

    1976-01-01

    This paper summarizes results obtained earlier from ESR studies of γ-irradiated n-alkane single crystals. It also contains some new experimental results that serve to give a more complete picture of the deposition of radiation energy in solid alkanes. The experiments performed with solid n-alkanes have thus far provided structural data that permit the nature and even the conformation of alkyl radicals to be clearly understood. Two types of radical exist namely, one where the unpaired electron is located next to the end methyl group and one with the unpaired electron in the interior of the chain. The first type has a conformation which differs from that of the undamaged molecule. Microwave saturation data show that there is a difference in relaxation properties of these radicals which can be understood in terms of a difference in mobility. Relative yield measurements give the distribution of isomeric alkyl, the result differing from that obtained using product analysis in liquids. For protiated n-alkanes n-alkyl is lacking and the 2-alkyl concentration is higher than expected. For deuterated n-alkanes the ESR spectrum is mainly that of radicals with the unpaired electron located in the interior of the carbon chain. This isotope effect is again contrary to observations in liquid n-alkanes. The broad lines observed in protiated alkanes irradiated at 77 K and deuterated alkanes irradiated at 4.2 K are not believed to arise from strong spin-spin interactions. They are thought instead to arise from distorted crystal and radical structures relating to the damaged regions of the crystals. (Auth.)

  7. Measurement and modelling of high pressure density and interfacial tension of (gas + n-alkane) binary mixtures

    International Nuclear Information System (INIS)

    Pereira, Luís M.C.; Chapoy, Antonin; Burgass, Rod; Tohidi, Bahman

    2016-01-01

    Highlights: • (Density + IFT) measurements are performed in synthetic reservoir fluids. • Measured systems include CO_2, CH_4 and N_2 with n-decane. • Novel data are reported for temperatures up to 443 K and pressures up to 69 MPa. • Predictive models are tested in 16 (gas + n-alkane) systems. • Best modelling results are achieved with the Density Gradient Theory. - Abstract: The deployment of more efficient and economical extraction methods and processing facilities of oil and gas requires the accurate knowledge of the interfacial tension (IFT) of fluid phases in contact. In this work, the capillary constant a of binary mixtures containing n-decane and common gases such as carbon dioxide, methane and nitrogen was measured. Experimental measurements were carried at four temperatures (313, 343, 393 and 442 K) and pressures up to 69 MPa, or near the complete vaporisation of the organic phase into the gas-rich phase. To determine accurate IFT values, the capillary constants were combined with saturated phase density data measured with an Anton Paar densitometer and correlated with a model based on the Peng–Robinson 1978 equation of state (PR78 EoS). Correlated density showed an overall percentage absolute deviation (%AAD) to measured data of (0.2 to 0.5)% for the liquid phase and (1.5 to 2.5)% for the vapour phase of the studied systems and P–T conditions. The predictive capability of models to accurately describe both the temperature and pressure dependence of the saturated phase density and IFT of 16 (gas + n-alkane) binary mixtures was assessed in this work by comparison with data gathered from the literature and measured in this work. The IFT models considered include the Parachor, the Linear Gradient Theory (LGT) and the Density Gradient Theory (DGT) approaches combined with the Volume-Translated Predictive Peng–Robinson 1978 EoS (VT-PPR78 EoS). With no adjustable parameters, the VT-PPR78 EoS allowed a good description of both solubility and

  8. Predominance of even carbon-numbered n-alkanes from lacustrine sediments in Linxia Basin, NE Tibetan Plateau: Implications for climate change

    Energy Technology Data Exchange (ETDEWEB)

    Wang Yongli [Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics, Chinese Academy of Sciences, Lanzhou 730000 (China)] [Institute of Tibetan and Plateau Research, Chinese Academy of Sciences, Beijing 100085 (China); Fang Xiaomin, E-mail: fangxm@itpcas.ac.cn [Institute of Tibetan and Plateau Research, Chinese Academy of Sciences, Beijing 100085 (China)] [Key Laboratory of Western Resources and Environment of Education Ministry, College at Earth and Environment Sciences, University of Lanzhou, Lanzhou 730000 (China); Zhang Tongwei [Key Laboratory of Western Resources and Environment of Education Ministry, College at Earth and Environment Sciences, University of Lanzhou, Lanzhou 730000 (China); Li Yuanmao; Wu Yingqin; He Daxiang; Wang Youxiao [Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics, Chinese Academy of Sciences, Lanzhou 730000 (China)

    2010-10-15

    Research highlights: {yields} This study reports the first observation of predominant even carbon-numbered n-alkanes of sediments in the continuous lacustrine-sedimentary section (Maogou) from the Late Miocene to the Early Pliocene (13-4.4 Ma) in the Linxia Basin, NE Tibetan Plateau. {yields} Certain types of special autochthonous bacteria are a possible source for the special distribution of even carbon-numbered n-alkanes in lacustrine sediments. {yields} These bacteria may have a high production rate in weak oxic-anoxic and arid depositional environments, in which a variety of geochemical parameters have recorded palaeoclimate change. {yields} A close correspondence among the low ratio of n-C{sub 27}/n-C{sub 31}, the heavy {delta}{sup 13}C values of TOC and a strong even carbon-number predominance (low OEP{sub 16-20} values) from approximately 6.5 to 4.4 Ma and at approximately 8 Ma in the studied section suggests that n-alkanes with a high predominance of even carbon-numbers may be treated as geochemical proxies for arid climate. - Abstract: This study reports the first observation of predominant even C-numbered n-alkanes from sediments in the continuous lacustrine-sedimentary section (Maogou) from the Late Miocene to the Early Pliocene (13-4.4 Ma) in the Linxia Basin, NE Tibetan Plateau. The n-alkanes showed a bimodal distribution that is characterised by a centre at n-C{sub 16}-n-C{sub 20} with maximum values at n-C{sub 18} and n-C{sub 27}-n-C{sub 31} as well as at n-C{sub 29}. The first mode shows a strong even C-number predominance (OEP{sub 16-20} 0.34-0.66). In contrast, the second mode has a strong odd C-number predominance (OEP{sub 27-31} 1.20-2.45). Certain types of special autochthonous bacteria are a possible source for this distribution of even C-numbered n-alkanes in lacustrine sediments. These bacteria may have a high production rate in weak oxic-anoxic and arid depositional environments, in which a variety of geochemical parameters have recorded

  9. Predominance of even carbon-numbered n-alkanes from lacustrine sediments in Linxia Basin, NE Tibetan Plateau: Implications for climate change

    International Nuclear Information System (INIS)

    Wang Yongli; Fang Xiaomin; Zhang Tongwei; Li Yuanmao; Wu Yingqin; He Daxiang; Wang Youxiao

    2010-01-01

    Research highlights: → This study reports the first observation of predominant even carbon-numbered n-alkanes of sediments in the continuous lacustrine-sedimentary section (Maogou) from the Late Miocene to the Early Pliocene (13-4.4 Ma) in the Linxia Basin, NE Tibetan Plateau. → Certain types of special autochthonous bacteria are a possible source for the special distribution of even carbon-numbered n-alkanes in lacustrine sediments. → These bacteria may have a high production rate in weak oxic-anoxic and arid depositional environments, in which a variety of geochemical parameters have recorded palaeoclimate change. → A close correspondence among the low ratio of n-C 27 /n-C 31 , the heavy δ 13 C values of TOC and a strong even carbon-number predominance (low OEP 16-20 values) from approximately 6.5 to 4.4 Ma and at approximately 8 Ma in the studied section suggests that n-alkanes with a high predominance of even carbon-numbers may be treated as geochemical proxies for arid climate. - Abstract: This study reports the first observation of predominant even C-numbered n-alkanes from sediments in the continuous lacustrine-sedimentary section (Maogou) from the Late Miocene to the Early Pliocene (13-4.4 Ma) in the Linxia Basin, NE Tibetan Plateau. The n-alkanes showed a bimodal distribution that is characterised by a centre at n-C 16 -n-C 20 with maximum values at n-C 18 and n-C 27 -n-C 31 as well as at n-C 29 . The first mode shows a strong even C-number predominance (OEP 16-20 0.34-0.66). In contrast, the second mode has a strong odd C-number predominance (OEP 27-31 1.20-2.45). Certain types of special autochthonous bacteria are a possible source for this distribution of even C-numbered n-alkanes in lacustrine sediments. These bacteria may have a high production rate in weak oxic-anoxic and arid depositional environments, in which a variety of geochemical parameters have recorded palaeoclimate change.

  10. Physical properties of {anisole + n-alkanes} at temperatures between (293.15 and 303.15) K

    International Nuclear Information System (INIS)

    Al-Jimaz, Adel S.; Al-Kandary, Jasem A.; Abdul-latif, Abdul-Haq M.; Al-Zanki, Adnan M.

    2005-01-01

    Density ρ, viscosity η, and refractive index n D , values of {anisole + hexane, or heptane, or octane, or nonane, or decane, or dodecane} binary mixtures over the entire range of mole fraction at temperatures (293.15, 298.15, and 303.15) K, have been investigated at atmospheric pressure. The excess molar volume V E , has been calculated from the experimental measurements. These results were fitted to Redlich and Kister polynomial equation to estimate the binary interaction parameters. The viscosity data were correlated with equations of Grunberg and Nissan, and McAllister. The refractive indices data were used to calculate the specific refractivity R 12 , and also correlated with Lorentz-Lorenz equation. While the excess molar volumes of {anisole + hexane} are negative, and {anisole + heptane} are sigmoidal S-shaped, the remaining binary mixtures are positive. The effects of n-alkanes chain length as well as the temperature on the excess molar volume have been studied. The calculated values have been qualitatively used to explain the intermolecular interaction between the mixing components

  11. Transport behavior of n-alkane penetrants into castor oil based polyurethane-polyester nonwoven fabric composites

    International Nuclear Information System (INIS)

    Satheesh Kumar, M.N.; Manjula, K.S.; Siddaramaiah

    2007-01-01

    Castor oil based polyurethane (PU)-polyester nonwoven fabric composites were fabricated by impregnating the polyester nonwoven fabric in a composition containing castor oil and diisocyanate. Composites were fabricated with two different isocyanates such as toluene-2,4-diisocyanate (TDI) and hexamethylene diisocyanate (HMDI). Transport behavior of n-alkane penetrants (pentane, hexane and heptane) into both PUs and PU-polyester nonwoven fabric composites were studied. Sorption studies were carried out at different temperatures. From the sorption results, the diffusion (D) and permeation (P) coefficients of penetrants have been calculated. Significant increase in the diffusion and permeation coefficients was observed with increase in the temperature of sorption experiments. Drastical reduction in diffusion and permeation coefficients was noticed in the composites compared to neat PUs. Attempts were made to estimate the empirical parameters like n, which suggests the mode of transport and K is a constant depends on the structural characteristics of the composite in addition to its interaction with penetrants. The temperature dependence of the transport coefficients has been used to estimate the activation energy parameter for diffusion (E D ) and permeation (E P ) processes from Arrhenius plots. Furthermore, the sorption results have been interpreted in terms of the thermodynamic parameters such as enthalpy (ΔH) and entropy (ΔS)

  12. Molecular dynamics simulations of diffusion and clustering along critical isotherms of medium-chain n-alkanes.

    Science.gov (United States)

    Mutoru, J W; Smith, W; O'Hern, C S; Firoozabadi, A

    2013-01-14

    Understanding the transport properties of molecular fluids in the critical region is important for a number of industrial and natural systems. In the literature, there are conflicting reports on the behavior of the self diffusion coefficient D(s) in the critical region of single-component molecular systems. For example, D(s) could decrease to zero, reach a maximum, or remain unchanged and finite at the critical point. Moreover, there is no molecular-scale understanding of the behavior of diffusion coefficients in molecular fluids in the critical regime. We perform extensive molecular dynamics simulations in the critical region of single-component fluids composed of medium-chain n-alkanes-n-pentane, n-decane, and n-dodecane-that interact via anisotropic united-atom potentials. For each system, we calculate D(s), and average molecular cluster sizes κ(cl) and numbers N(cl) at various cluster lifetimes τ, as a function of density ρ in the range 0.2ρ(c) ≤ ρ ≤ 2.0ρ(c) at the critical temperature T(c). We find that D(s) decreases with increasing ρ but remains finite at the critical point. Moreover, for any given τ critical point.

  13. Fabrication, thermal properties and thermal stabilities of microencapsulated n-alkane with poly(lauryl methacrylate) as shell

    International Nuclear Information System (INIS)

    Qiu, Xiaolin; Lu, Lixin; Wang, Ju; Tang, Guoyi; Song, Guolin

    2015-01-01

    Highlights: • Microencapsulation of octadecane and paraffin by crosslinked poly(lauryl methacrylate). • Octadecane microcapsules have a melting enthalpy of about 118 J g −1 . • Weight loss temperatures of the microcapsules were increased by 67 °C and 28 °C. • Phase change enthalpies decreased by around 10 wt% after 500 thermal cycles. • Foams with microcapsules can be applied for passive temperature control. - Abstract: Microencapsulation of n-octadecane or paraffin with poly(lauryl methacrylate) (PLMA) shell was performed by a suspension-like polymerization. The polymer shell was crosslinked by pentaerythritol tetraacrylate (PETRA). The surface morphologies of microcapsules were investigated by scanning electron microscopy (SEM). Phase change properties, thermal reliabilities and thermal stabilities of microcapsules were determined by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The n-octadecane microcapsule exhibits higher melting enthalpy (118.0 J g −1 ) and crystallization enthalpy (108.3 J g −1 ) compared with the paraffin microcapsule. The thermal resistant temperatures were enhanced by more than 25 °C when n-alkanes were microencapsulated by PLMA. The PCM contents of microcapsules decreased by less than 4 wt% and 6 wt% after 500 and 1000 thermal cycles, respectively. Heat-up experiments indicated that microcapsule-treated foams exhibited upgraded thermal regulation capacities. Consequently, microencapsulated n-octadecane or paraffin with PLMA as shell possesses good potentials for heat storage and thermal regulation.

  14. Effects of chain length, chlorination degree, and structure on the octanol-water partition coefficients of polychlorinated n-alkanes.

    Science.gov (United States)

    Hilger, Bettina; Fromme, Hermann; Völkel, Wolfgang; Coelhan, Mehmet

    2011-04-01

    Log octanol-water partition coefficients (log Kow) of 40 synthesized polychlorinated n-alkanes (PCAs) with different chlorination degrees were determined using reversed-phase high performance liquid chromatography (RP-HPLC). In addition, log Kow values of a technical mixture namely Cereclor 63L as well as 15 individual in house synthesized C10, C11, and C12 chloroalkanes with known chlorine positions were estimated. Based on these results, the effects of chain length, chlorination degree, and structure were explored. The estimated log Kow values ranged from 4.10 (polychlorinated n-decanes with 50.2% chlorine content) to 11.34 (polychlorinated n-octacosanes with 54.8% chlorine content) for PCAs and from 3.82 (1,2,5,6,9,10-hexachlorodecane) to 7.75 (1,1,1,3,9,11,11,11-octachlorododecane) for the individual chloroalkanes studied. The results showed that log Kow value was influenced linearly at a given chlorine content by chain length, while a polynominal effect was observed in dependence on the chlorination degree of an alkane chain. Chlorine substitution pattern influenced markedly the log Kow value of chloroalkanes.

  15. High Amounts of n-Alkanes in the Composition of Asphodelus aestivus Brot. Flower Essential Oil from Cyprus.

    Science.gov (United States)

    Polatoğlu, Kaan; Demirci, Betül; Can Başer, Kemal Hüsnü

    2016-10-01

    There is only a couple of reports indicating essential oil composition of Asphodelus species in the literature. However, from the members of this genus many non-volatile secondary metabolites were isolated. In Cyprus, Asphodelus aestivus Brot. can be found abundantly in all regions of the island. This plant has various ethnobotanical uses in Cyprus. There is no report on the volatiles nor the essential oil composition of A. aestivus. The smell of A. aestivus flowers resembles that of a cat pee which caught our attention. Therefore, we have carried out GC, GC/MS analysis of the essential oil (yield: 0.01 v/w) obtained from Asphodelus aestivus flowers. Seventeen compounds were identified in the essential oil comprising 96.2% of the oil. The major components of the essential oil were hexadecanoic acid 35.6%, pentacosane 17.4%, tricosane 13.4% and heptacosane 8.4%. In our results, we expected to see sulfur containing cat pee odorants due to the odor of the flower whereas high amounts of n-alkanes, saturated fatty acids and minor amounts of acyclic diterpenes were observed.

  16. Fabrication, thermal properties and thermal stabilities of microencapsulated n-alkane with poly(lauryl methacrylate) as shell

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Xiaolin, E-mail: shirleyqiu2009@gmail.com [Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology, School of Mechanical Engineering, Jiangnan University, Wuxi 214122 (China); Lu, Lixin; Wang, Ju [Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology, School of Mechanical Engineering, Jiangnan University, Wuxi 214122 (China); Tang, Guoyi [Advanced Materials Institute and Clearer Production Key Laboratory, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Key Laboratory of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Haidian District, Beijing 100084 (China); Song, Guolin [Advanced Materials Institute and Clearer Production Key Laboratory, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China)

    2015-11-20

    Highlights: • Microencapsulation of octadecane and paraffin by crosslinked poly(lauryl methacrylate). • Octadecane microcapsules have a melting enthalpy of about 118 J g{sup −1}. • Weight loss temperatures of the microcapsules were increased by 67 °C and 28 °C. • Phase change enthalpies decreased by around 10 wt% after 500 thermal cycles. • Foams with microcapsules can be applied for passive temperature control. - Abstract: Microencapsulation of n-octadecane or paraffin with poly(lauryl methacrylate) (PLMA) shell was performed by a suspension-like polymerization. The polymer shell was crosslinked by pentaerythritol tetraacrylate (PETRA). The surface morphologies of microcapsules were investigated by scanning electron microscopy (SEM). Phase change properties, thermal reliabilities and thermal stabilities of microcapsules were determined by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The n-octadecane microcapsule exhibits higher melting enthalpy (118.0 J g{sup −1}) and crystallization enthalpy (108.3 J g{sup −1}) compared with the paraffin microcapsule. The thermal resistant temperatures were enhanced by more than 25 °C when n-alkanes were microencapsulated by PLMA. The PCM contents of microcapsules decreased by less than 4 wt% and 6 wt% after 500 and 1000 thermal cycles, respectively. Heat-up experiments indicated that microcapsule-treated foams exhibited upgraded thermal regulation capacities. Consequently, microencapsulated n-octadecane or paraffin with PLMA as shell possesses good potentials for heat storage and thermal regulation.

  17. Degradation of Hydrocarbons by Members of the Genus Candida II. Oxidation of n-Alkanes and 1-Alkenes by Candida lipolytica

    Science.gov (United States)

    Klug, M. J.; Markovetz, A. J.

    1967-01-01

    Candida lipolytica ATCC 8661 was grown in a mineral-salts hydrocarbon medium. n-Alkanes and 1-alkenes with 14 through 18 carbon atoms were used as substrates. Ether extracts of culture fluids and cells obtained from cultures grown on the various substrates were analyzed by thin-layer and gas-liquid chromatography. Analyses of fluids from cultures grown on n-alkanes indicated a predominance of fatty acids and alcohols of the same chain length as the substrate. In addition, numerous other fatty acids and alcohols were present. Analyses of saponifiable and nonsaponifiable material obtained from the cells revealed essentially the same products. The presence of primary and secondary alcohols, as well as fatty acids, of the same chain length as the n-alkane substrate suggested that attack on both the methyl and α-methylene group was occurring. The significance of these two mechanisms in the degradation of n-alkanes by this organism was not evident from the data presented. Analyses of fluids from cultures grown on 1-alkenes indicated the presence of 1,2-diols, as well as ω-unsaturated fatty acids, of the same chain length as the substrate. Alcohols present were all unsaturated. Saponifiable and nonsaponifiable material obtained from cells contained essentially the same products. The presence of 1,2-diols and ω-unsaturated fatty acids of the same chain length as the substrate from cultures grown on 1-alkenes indicated that both the terminal methyl group and the terminal double bond were being attacked. PMID:6025303

  18. Growth of Rhodococcus sp. strain BCP1 on gaseous n-alkanes: new metabolic insights and transcriptional analysis of two soluble di-iron monooxygenase genes

    Directory of Open Access Journals (Sweden)

    Martina eCappelletti

    2015-05-01

    Full Text Available Rhodococcus sp. strain BCP1 was initially isolated for its ability to grow on gaseous n-alkanes, which act as inducers for the co-metabolic degradation of low-chlorinated compounds. Here, both molecular and metabolic features of BCP1 cells grown on gaseous and short-chain n-alkanes (up to n-heptane were examined in detail. We show that propane metabolism generated terminal and sub-terminal oxidation products such as 1- and 2-propanol, whereas 1-butanol was the only terminal oxidation product detected from butane metabolism. Two gene clusters, prmABCD and smoABCD – coding for soluble di-iron monooxgenases (SDIMOs involved in gaseous n-alkanes oxidation – were detected in the BCP1 genome. By means of reverse transcriptase-quantitative PCR (RT-qPCR analysis, a set of substrates inducing the expression of the sdimo genes in BCP1 were assessed as well as their transcriptional repression in the presence of sugars, organic acids or during the cell growth on rich medium (Luria Bertani broth. The transcriptional start sites of both the sdimo gene clusters were identified by means of primer extension experiments. Finally, proteomic studies revealed changes in the protein pattern induced by growth on gaseous- (n-butane and/or liquid (n-hexane short-chain n-alkanes as compared to growth on succinate. Among the differently expressed protein spots, two chaperonins and an isocytrate lyase were identified along with oxidoreductases involved in oxidation reactions downstream of the initial monooxygenase reaction step.

  19. Growth of Rhodococcus sp. strain BCP1 on gaseous n-alkanes: new metabolic insights and transcriptional analysis of two soluble di-iron monooxygenase genes

    Science.gov (United States)

    Cappelletti, Martina; Presentato, Alessandro; Milazzo, Giorgio; Turner, Raymond J.; Fedi, Stefano; Frascari, Dario; Zannoni, Davide

    2015-01-01

    Rhodococcus sp. strain BCP1 was initially isolated for its ability to grow on gaseous n-alkanes, which act as inducers for the co-metabolic degradation of low-chlorinated compounds. Here, both molecular and metabolic features of BCP1 cells grown on gaseous and short-chain n-alkanes (up to n-heptane) were examined in detail. We show that propane metabolism generated terminal and sub-terminal oxidation products such as 1- and 2-propanol, whereas 1-butanol was the only terminal oxidation product detected from n-butane metabolism. Two gene clusters, prmABCD and smoABCD—coding for Soluble Di-Iron Monooxgenases (SDIMOs) involved in gaseous n-alkanes oxidation—were detected in the BCP1 genome. By means of Reverse Transcriptase-quantitative PCR (RT-qPCR) analysis, a set of substrates inducing the expression of the sdimo genes in BCP1 were assessed as well as their transcriptional repression in the presence of sugars, organic acids, or during the cell growth on rich medium (Luria–Bertani broth). The transcriptional start sites of both the sdimo gene clusters were identified by means of primer extension experiments. Finally, proteomic studies revealed changes in the protein pattern induced by growth on gaseous- (n-butane) and/or liquid (n-hexane) short-chain n-alkanes as compared to growth on succinate. Among the differently expressed protein spots, two chaperonins and an isocytrate lyase were identified along with oxidoreductases involved in oxidation reactions downstream of the initial monooxygenase reaction step. PMID:26029173

  20. High frequency of Thermodesulfovibrio spp. and Anaerolineaceae in association with Methanoculleus spp. in a long-term incubation of n-alkanes-degrading methanogenic enrichment culture

    Directory of Open Access Journals (Sweden)

    Bo Liang

    2016-09-01

    Full Text Available In the present study, the microbial community and functional gene composition of a long-term active alkane-degrading methanogenic culture was established after two successive enrichment culture transfers and incubated for a total period of 1750 days. Molecular analysis was conducted after the second transfer (incubated for 750 days for both the active alkanes-degrading methanogenic enrichment cultures (T2-AE and the background control (T2-BC. A net increase of methane as the end product was detected in the headspace of the enrichment cultures amended with long-chain n-alkanes and intermediate metabolites, including octadecanoate, hexadecanoate, isocaprylate, butyrate, isobutyrate, propionate, acetate and formate were measured in the liquid cultures. The composition of microbial community shifted through the successive transfers over time of incubation. Sequences of bacterial and archaeal 16S rRNA gene (16S rDNA and mcrA functional gene indicated that bacterial sequences affiliated to Thermodesulfovibrio spp. and Anaerolineaceae and archaeal sequences falling within the genus Methanoculleus were the most frequently encountered and thus represented the dominant members performing the anaerobic degradation of long-chain n-alkanes and methanogenesis. In addition, the presence of assA functional genes encoding the alkylsuccinate synthase α subunit indicated that fumarate addition mechanism could be considered as a possible initial activation step of n-alkanes in the present study. The succession pattern of microbial communities indicates that Thermodesulfovibrio spp. could be a generalist participating in the metabolism of intermediates, while Anaerolineaceae plays a key role in the initial activation of long-chain n-alkane biodegradation.

  1. Solvent extraction of thiophene from n-alkanes (C7, C12, and C16) using the ionic liquid [C8mim][BF4

    International Nuclear Information System (INIS)

    Alonso, Luisa; Arce, Alberto; Francisco, Maria; Soto, Ana

    2008-01-01

    In the last years, new strict environmental regulations to reduce sulfur content in liquid fuels have been established. Thiophene derivates can be considered as the key substances to be separated from liquid fuel oils. This paper reports the ability of the ionic liquid 1-methyl-3-octylimidazolium tetrafluoroborate to act as solvent in the (liquid + liquid) extraction of thiophene from aliphatic hydrocarbons. Tie-line data have been determined for ternary systems containing the ionic liquid, thiophene, and some n-alkanes at T = 298.15 K. Extraction process has been analyzed by means of thiophene distribution ratio and selectivity. The solute distribution coefficient decreases and the selectivity increases as the chain length of n-alkane increases. The use of 1-methyl-3-octylimidazolium tetrafluoroborate as potential solvent for separation of thiophene from n-alkanes is feasible using the necessary quantity of solvent. A correlation of the equilibrium data reported here has also been made, using the NRTL activity coefficient model, in order to facilitate their use in simulation and design processes

  2. Plant Wax n-Alkane and n-Alkanoic Acid Signatures Overprinted by Microbial Contributions and Old Carbon in Meromictic Lake Sediments

    Science.gov (United States)

    Makou, Matthew; Eglinton, Timothy; McIntyre, Cameron; Montluçon, Daniel; Antheaume, Ingrid; Grossi, Vincent

    2018-01-01

    Specific n-alkanes and n-alkanoic acids are commonly used as biomarkers in paleoenvironmental reconstruction, yet any individual homologue may originate from multiple biological sources. Here we improve source and age controls for these compounds in meromictic systems by measuring the radiocarbon (14C) ages of specific homologues preserved in twentieth century Lake Pavin (France) sediments. In contrast to many studies, 14C ages generally decreased with increasing carbon chain length, from 7.3 to 2.6 ka for the C14-C30 n-alkanoic acids and from 9.2 to 0.3 ka for the C21-C33 n-alkanes. Given a known hard water effect, these values suggest that aquatic microbial sources predominate and contributed to most of the homologues measured. Only the longest chain n-alkanes exclusively represent inputs of higher plant waxes, which were previously sequestered in soils over centennial to millennial timescales prior to transport and deposition. These findings suggest that biomarker source and age should be carefully established for lacustrine settings.

  3. ESR study of n-alkane cation structure and photodecomposition in γ-irradiated frozen solutions of CF3CCl3

    International Nuclear Information System (INIS)

    Tabata, M.; Lund, A.

    1984-01-01

    Cations of several n-alkanes produced by γ-irradiation at 77 K of a CF 3 CCl 3 matrix containing 0.1 to 2 mole% of solute have been investigated with special emphasis on their photo-induced decomposition. A general route of reaction of n-alkane cations containing 4 to 7 chain carbon atoms involves the formation of 2-butene cation probably in a process of the type Csub(n)H + sub(2n+2) -> 2-C 4 H 8 + + Csub(n-4)Hsub(2n-6). This reaction is exothermic, but does not occur thermally over the temperature interval 77 to 140 K. The variation of the ESR spectral data of the parent cations have been investigated over the temperature interval 4 to 140 K and have been compared with data obtained using other matrices. It is concluded that the assumption of an extended conformation of the n-alkane cation is not always valid and that the structure is sensitive to matrix and temperature effects. (author)

  4. Carbon and Hydrogen Isotopic Composition of Plant Wax n-Alkanes: A Tool for Characterizing Soil Provenance in Forensic Science

    Science.gov (United States)

    Pedentchouk, N.; Wagner, T.; Jones, M.

    2009-04-01

    Forensic science is an integrative discipline that requires material evidence from diverse sources. Geochemical evidence derived from inorganic and organic substances is becoming increasingly popular among law enforcement agencies in industrialized countries. Previous investigations indicate that the relative distributions of individual plant-derived biomarkers found in soils are linked to the biomarker patterns found in the overlying vegetation. However, identification of soil provenance based on the distribution of plant-derived biomarkers for forensic purposes is inhibited by the fact that a significant number of terrestrial plant species have overlapping biomarker distributions. In order to enhance the resolving power of plant-derived biomarker signal, we propose to enhance the molecular approach by adding a stable isotope component, i.e. the delta13C/deltaD values of individual biomarkers. The first objective of this project is to determine the delta13C/deltaD signatures of n-alkanes derived from various higher plant types commonly growing in the UK. The second objective is to investigate whether the same species/plant types differ isotopically between two locations affected by different weather patterns in the UK: a relatively warmer and drier Norwich, Norfolk and a cooler and wetter Newcastle-upon-Tyne in NE England. The n-C29 alkane data from 14 tree species sampled during July 2007 and August 2008 in Newcastle show a clear negative trend between delta13C and deltaD values. When these data are plotted against each other, the six deciduous angiosperms (delta13C: c. -39 to -35 per mil; deltaD: c. -155 to -130 per mil) are completely separated from four evergreen angiosperms (delta13C: c. -33 to -28 per mil; deltaD: c. -195 to -165 per mil). The four gymnosperm species data plot between those of the deciduous and evergreen angiosperms. Because all 14 species in Newcastle experience the same environmental conditions, we suggest that the observed isotopic

  5. Predictions of homogeneous nucleation rates for n-alkanes accounting for the diffuse phase interface and capillary waves.

    Science.gov (United States)

    Planková, Barbora; Vinš, Václav; Hrubý, Jan

    2017-10-28

    Homogeneous droplet nucleation has been studied for almost a century but has not yet been fully understood. In this work, we used the density gradient theory (DGT) and considered the influence of capillary waves (CWs) on the predicted size-dependent surface tensions and nucleation rates for selected n-alkanes. The DGT model was completed by an equation of state (EoS) based on the perturbed-chain statistical associating fluid theory and compared to the classical nucleation theory and the Peng-Robinson EoS. It was found that the critical clusters are practically free of CWs because they are so small that even the smallest wavelengths of CWs do not fit into their finite dimensions. The CWs contribute to the entropy of the system and thus decrease the surface tension. A correction for the effect of CWs on the surface tension is presented. The effect of the different EoSs is relatively small because by a fortuitous coincidence their predictions are similar in the relevant range of critical cluster sizes. The difference of the DGT predictions to the classical nucleation theory computations is important but not decisive. Of the effects investigated, the most pronounced is the suppression of CWs which causes a sizable decrease of the predicted nucleation rates. The major difference between experimental nucleation rate data and theoretical predictions remains in the temperature dependence. For normal alkanes, this discrepancy is much stronger than observed, e.g., for water. Theoretical corrections developed here have a minor influence on the temperature dependency. We provide empirical equations correcting the predicted nucleation rates to values comparable with experiments.

  6. Characterization of sorbent properties of soil organic matter and carbonaceous geosorbents using n-alkanes and cycloalkanes as molecular probes.

    Science.gov (United States)

    Endo, Satoshi; Grathwohl, Peter; Haderlein, Stefan B; Schmidt, Torsten C

    2009-01-15

    Nonspecific interactions and modes (i.e., adsorption vs absorption) of sorption by noncondensed, amorphous organic phases (here termed organic matter; OM) in soils and by rigid, aromatic, and condensed phases (termed carbonaceous geosorbents; CGs) were investigated using n-alkanes and cycloalkanes as molecular probes. Sorption isotherms of n- and cyclooctane from water for seven CGs (charcoal, lignite coke, activated carbon, graphite, partially oxidized graphite, diesel soot, bituminous coal), four sorbents with a predominance of OM (lignite, peat, two sapric soils), and two soils containing OM and high amounts of CGs were measured in batch systems. The peat and the sapric soils showed extensively linear sorption, while the CGs exhibited highly nonlinear (Freundlich exponents 0.2-0.7) and strong (Koc values being up to 10(5) times those for the OM-rich materials at low concentrations) sorption for the alkanes studied, showing that enhanced sorption by CGs can occur to completely apolar sorbates that do not undergo any specific interaction. Sorption by CGs was generally stronger and more nonlinear for n-octane than for cyclooctane, which suggests a strong dependence of sorption on the 3-D structure of sorbate molecules. The n-octane-to-cyclooctane sorption coefficient ratios (Kn/Kc) for adsorption to CGs were > or = 1, being distinctly different from those for absorption to the OM-rich materials (Kn/Kc soils determined by quantitative petrography analysis suggest, however, that CGs occurring in soils may be far less effective sorbents than the reference CGs used in the sorption experiments at least for nonspecifically interacting sorbates, probably because of competitive sorption and/or pore blocking by natural OM. The presented approaches and results offer a basis for interpreting sorption data for other organic compounds, as nonspecific interactions and sorption modes are relevant for any compound.

  7. Predictions of homogeneous nucleation rates for n-alkanes accounting for the diffuse phase interface and capillary waves

    Science.gov (United States)

    Planková, Barbora; Vinš, Václav; Hrubý, Jan

    2017-10-01

    Homogeneous droplet nucleation has been studied for almost a century but has not yet been fully understood. In this work, we used the density gradient theory (DGT) and considered the influence of capillary waves (CWs) on the predicted size-dependent surface tensions and nucleation rates for selected n-alkanes. The DGT model was completed by an equation of state (EoS) based on the perturbed-chain statistical associating fluid theory and compared to the classical nucleation theory and the Peng-Robinson EoS. It was found that the critical clusters are practically free of CWs because they are so small that even the smallest wavelengths of CWs do not fit into their finite dimensions. The CWs contribute to the entropy of the system and thus decrease the surface tension. A correction for the effect of CWs on the surface tension is presented. The effect of the different EoSs is relatively small because by a fortuitous coincidence their predictions are similar in the relevant range of critical cluster sizes. The difference of the DGT predictions to the classical nucleation theory computations is important but not decisive. Of the effects investigated, the most pronounced is the suppression of CWs which causes a sizable decrease of the predicted nucleation rates. The major difference between experimental nucleation rate data and theoretical predictions remains in the temperature dependence. For normal alkanes, this discrepancy is much stronger than observed, e.g., for water. Theoretical corrections developed here have a minor influence on the temperature dependency. We provide empirical equations correcting the predicted nucleation rates to values comparable with experiments.

  8. Dotriacontane-16,17-14C distribution pattern in the respiratory system of two hamster species after passive exposure to radioactive labelled smoke

    International Nuclear Information System (INIS)

    Kmoch, N.; Mohr, U.

    1974-01-01

    The quantitative and qualitative distribution of 14 C labeled dotriacontane (DOT- 14 C) determined by liquid scintillation counting and autoradiography in the respiratory system, the digestive tract, liver and kidneys of Syrian golden and European hamsters, males and females, is described after they had been exposed to radioactive labeled cigarette smoke. The different DOT- 14 C distributions are discussed in detail with special attention given to the respiratory tract, related species differences and the topographic subdivisions of apex nasi, fundus nasi, pharynx, larynx, trachea, and lungs. It is apparent that the absolute amount of activity in the respiratory tract related to body size of the Syrian golden hamster is greater than in the European hamster but that the percentual distribution exhibits a greater filtering action of the upper respiratory tract of Syrian golden hamster than of the European hamster so that a larger percentual amount of total inhaled particulate matter reaches the lungs. The European hamster might be a more useful model for the investigation of respiratory tract carcinogenesis due to the possibility of a longer life time exposure and a higher sensitivity to respiratory tract carcinogens

  9. Size-distributions of n-alkanes, PAHs and hopanes and their sources in the urban, mountain and marine atmospheres over East Asia

    Directory of Open Access Journals (Sweden)

    Z. Wang

    2009-11-01

    Full Text Available Size-segregated (9 stages n-alkanes, polycyclic aromatic hydrocarbons (PAHs and hopanes in the urban (Baoji city in inland China, mountain (Mt. Tai in east coastal China and marine (Okinawa Island, Japan atmospheres over East Asia were studied using a GC/MS technique. Ambient concentrations of n-alkanes (1698±568 ng m−3 in winter and 487±145 ng m−3 in spring, PAHs (536±80 and 161±39 ng m−3, and hopanes (65±24 and 20±2.4 ng m−3 in the urban air are 1–2 orders of magnitude higher than those in the mountain aerosols and 2–3 orders of magnitude higher than those in the marine samples. Mass ratios of n-alkanes, PAHs and hopanes clearly demonstrate coal-burning emissions as their major source. Size distributions of fossil fuel derived n-alkane, PAHs and hopanes were found to be unimodal in most cases, peaking at 0.7–1.1 μm size. In contrast, plant wax derived n-alkanes presented a bimodal distribution with two peaks at the sizes of 0.7–1.1 μm and >4.7 μm in the summer mountain and spring marine samples. Among the three types of samples, geometric mean diameter (GMD of the organics in fine mode (<2.1 μm was found to be smallest (av. 0.63 μm in spring for the urban samples and largest (1.01 μm for the marine samples, whereas the GMD in coarse mode (≥2.1 μm was found to be smallest (3.48 μm for the marine aerosols and largest (4.04 μm for the urban aerosols. The fine mode GMDs of the urban and mountain samples were larger in winter than in spring and summer. Moreover, GMDs of 3- and 4-ring PAHs were larger than those of 5- and 6-ring PAHs in the three types of atmospheres. Such differences in GMDs can be interpreted by the repartitioning of organic compounds and the coagulation and hygroscopic growth of particles during a long-range transport from the inland continent to the marine area, as well as the difference in their sources among the three regions.

  10. Prediction of the vapor–liquid equilibria and speed of sound in binary systems of 1-alkanols and n-alkanes with the simplified PC-SAFT equation of state

    DEFF Research Database (Denmark)

    Liang, Xiaodong; Thomsen, Kaj; Yan, Wei

    2013-01-01

    (or other derivative properties) with satisfactory accuracy over wide temperature, pressure and composition conditions. This work presents the prediction of the vapor–liquid equilibria and speed of sound in binary mixtures of 1-alkanols and n-alkanes using the simplified PC-SAFT equation of state...... of sound with a satisfactory accuracy for 1-alkanols and n-alkanes binary systems within the PC-SAFT framework....

  11. Degradation of n-alkanes and PAHs from the heavy crude oil using salt-tolerant bacterial consortia and analysis of their catabolic genes.

    Science.gov (United States)

    Gurav, Ranjit; Lyu, Honghong; Ma, Jianli; Tang, Jingchun; Liu, Qinglong; Zhang, Hairong

    2017-04-01

    In the present study, salt-tolerant strains, Dietzia sp. HRJ2, Corynebacterium variabile HRJ4, Dietzia cinnamea HRJ5 and Bacillus tequilensis HRJ6 were isolated from the Dagang oil field, China. These strains degraded n-alkanes and polycyclic aromatic hydrocarbons (PAHs) aerobically from heavy crude oil (HCO) in an experiment at 37 °C and 140 rpm. The GC/MS investigation for degradation of different chain lengths of n-alkanes (C8-C40) by individual strains showed the highest degradation of C8-C19 (HRJ5), C20-C30 (HRJ4) and C31-C40 (HRJ5), respectively. Moreover, degradation of 16 PAHs with individual strains demonstrated that the bicyclic and pentacyclic aromatic hydrocarbons (AHs) were mostly degraded by HRJ5, tricyclic and tetracyclic AHs by HRJ6 and hexacyclic AHs by HRJ2. However, the highest degradation of total petroleum hydrocarbons (TPHs), total saturated hydrocarbons (TSH), total aromatic hydrocarbons (TAH), n-alkanes (C8-C40) and 16 PAHs was achieved by a four-membered consortium (HRJ2 + 4 + 5 + 6) within 12 days, with the predominance of HRJ4 and HRJ6 strains which was confirmed by denaturing gradient gel electrophoresis. The abundance of alkB and nah genes responsible for catabolism of n-alkanes and PAHs was quantified using the qPCR. Maximum copy numbers of genes were observed in HRJ2 + 4 + 5 + 6 consortium (gene copies l -1 ) 2.53 × 10 4 (alkB) and 3.47 × 10 3 (nah) at 12 days, which corresponded to higher degradation rates of petroleum hydrocarbons. The superoxide dismutase (SOD) (total SOD (T-SOD), Cu 2+ Zn 2+ -SOD), catalase (CAT) and ascorbate peroxidase (APX) activities in Allium sativum and Triticum aestivum were lower in the HRJ2 + 4 + 5 + 6-treated HCO as compared to the plantlets exposed directly to HCO. The present results revealed the effective degradation of HCO-contaminated saline medium using the microbial consortium having greater metabolic diversity.

  12. Polycyclic aromatic hydrocarbons (PAHs) and n-Alkanes in beaked sea snake Enhydrina schistose (Daudin, 1803) from the Mandovi Estuary, Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Mote, S.; RanjeetKumar; Naik, B.G.; Ingole, B.S.

    , occur in high abundances (Voris H K 1985; Aaron Lobo et al. 2004) Present study demonstrates the tissue specific distribution of 15 EPA priority PAHs and 27 n-alkanes compounds in two individuals of E. schistose. We used GC-MS for analysis, which... in 20 ml dichloromethane/hexane (1:3 v/v) with surrogate internal standard (SIS) 20 ppm-200μl Tetracosane-d50 for alkane, 5ppm-200μl Chrysene-d12 for PAHs were spiked and transferred to 5% H2O deactivated silica gel column (1 cm i.dx 9 cm). Elution...

  13. Photochemical oxidation of short-chain polychlorinated n-alkane mixtures using H2O2/UV and the photo-Fenton reaction

    OpenAIRE

    Ken J. Friesen; Taha M. El-Morsi; Alaa S. Abd-El-Aziz

    2004-01-01

    The photochemical oxidation of a series of short-chain polychlorinated n-alkane (PCA) mixtures was investigated using H2O2/UV and modified photo-Fenton conditions (Fe3+/H2O2/UV) in both Milli-Q and lake water. All PCA mixtures, including chlorinated (Cl5 to Cl8) decanes, undecanes, dodecanes and tridecanes degraded in 0.02 M H2O2/UV at pH 2.8 in pure water, with 80±4% disappearance after 3 h of irradiation using a 300 nm light source. Degradation was somewhat enhanced under similar conditions...

  14. Equation of state modeling of the phase equilibria of asymmetric CO2+n-alkane binary systems using mixing rules cubic with respect to mole fraction

    DEFF Research Database (Denmark)

    Cismondi, Martin; Mollerup, Jørgen M.; Zabaloy, Marcelo S.

    2010-01-01

    for a great diversity of mixtures. Nevertheless, the models for representing phase equilibria and physico-chemical properties of asymmetric systems may require more flexible mixing rules than the classical quadratic van der Waals (vdW) mixing rules or their equivalent (with regard to the number of available...... interaction parameters) in modern equations of state.In particular, the phase equilibria of binary mixtures containing CO2 and heavy n-alkanes have been studied by an important number of authors and using different types of models, achieving only partially accurate results and realizing the difficulties...

  15. Excess molar volumes of the ternary system {methylcyclohexane (1)+cyclohexane (2)+n-alkanes (3)} at T=298.15 K

    International Nuclear Information System (INIS)

    Iloukhani, Hossein; Rezaei-Sameti, Mahdi

    2005-01-01

    Densities were experimentally determined in the whole range of composition at T=298.15 K for the ternary system {methylcyclohexane (1)+cyclohexane (2)+n-alkanes (3)} and for the seven corresponding binary systems. The n-alkanes include n-hexane, n-heptane, and n-octane. Excess molar volumes, V E , were calculated for the binaries and ternaries systems. The V 123 E data are positive over the entire range of composition for the systems {methylcyclohexane (1)+cyclohexane (2)+n-heptane (3) or n-octane (3)} at three fixed compositions (f m =X 1 /X 2 ). For the system {methylcyclohexane (1)+cyclohexane (2)+n-hexane (3)}, the V E values showed positive for f m =0.3 and negative for f m =3. The V E data exhibit, an inversion in sign in the mixture containing f m =1 for later ternary system. Several empirical expressions are used to predict and correlate the ternary excess molar volumes from experimental results on the constituted binaries and analyzed to gain insight about liquid mixture interactions

  16. Excess molar enthalpies of binary mixtures containing 2-decanone or dipentyl ether with long-chain n-alkanes at T = 298.15 K

    International Nuclear Information System (INIS)

    Liao, Wei-Chen; Lin, Ho-mu; Lee, Ming-Jer

    2011-01-01

    Research highlights: → An isothermal titration calorimeter was used for enthalpy data measurment. → The investigated systems are 2-decanone or dipentyl ether with long-chain n-alkanes. → The excess enthalpies are all positive over entire composition range. → The Patel-Teja equation of state with two parameters gives the best representation. - Abstract: Excess molar enthalpies (H E ) of binary mixtures of 2-decanone or dipentyl ether with n-alkanes, including n-dodecane, n-tetradecane, and n-hexadecane, were measured with an isothermal titration calorimeter (ITC) at T = 298.15 K under atmospheric pressure. All the measured H E values are positive over the entire range of composition, indicating that all these mixing processes are endothermic. The H E values varying with composition are found to be nearly symmetric for each binary system. It was also shown that the H E values follow the order of n-hexadecane > n-tetradecane > n-dodecane at a given composition in either the 2-decanone or dipentyl ether binary systems. An empirical Redlich-Kister equation correlated quantitatively these new H E data. The Peng-Robinson and the Patel-Teja equations of state, and the NRTL model were also applied to fit the H E results. Among these tested correlative models, the Patel-Teja equation of state with two adjustable binary interaction parameters generally yielded the best representation.

  17. n-Alkane and clofibrate, a peroxisome proliferator, activate transcription of ALK2 gene encoding cytochrome P450alk2 through distinct cis-acting promoter elements in Candida maltosa

    International Nuclear Information System (INIS)

    Kogure, Takahisa; Takagi, Masamichi; Ohta, Akinori

    2005-01-01

    The ALK2 gene, encoding one of the n-alkane-hydroxylating cytochromes P450 in Candida maltosa, is induced by n-alkanes and a peroxisome proliferator, clofibrate. Deletion analysis of this gene's promoter revealed two cis-acting elements-an n-alkane-responsive element (ARE2) and a clofibrate-responsive element (CRE2)-that partly overlap in sequence but have distinct functions. ARE2-mediated activation responded to n-alkanes but not to clofibrate and was repressed by glucose. CRE2-mediated activation responded to polyunsaturated fatty acids and steroid hormones as well as to peroxisome proliferators but not to n-alkanes, and it was not repressed by glucose. Both elements mediated activation by oleic acid. Mutational analysis demonstrated that three CCG sequences in CRE2 were critical to the activation by clofibrate as well as to the in vitro binding of a specific protein to this element. These findings suggest that ALK2 is induced by peroxisome proliferators and steroid hormones through a specific CRE2-mediated regulatory mechanism

  18. Heat and Mass Transfer during Solid-Liquid Phase Transition of n-Alkanes in the C{sub 16} to C{sub 19} Range

    Energy Technology Data Exchange (ETDEWEB)

    Holmen, Rune

    2002-07-01

    The main goal of this project has been to study heat and mass transfer during solid-liquid phase transition of n-alkanes in the in the C{sub 16} to C{sub 19} range. Phase transitions of both mixtures and pure components have been investigated. All experiments and simulations have been performed without any convection. Thermal conductivities have been determined at the melting point for solid and liquid unbranched alkanes ranging from C{sub 16} to C{sub 19}. An assessment of the error of the method has been performed. The measurements of solid conductivities are in accordance with measurements reported previously and confirm the applicability of the method. Liquid conductivities are higher than extrapolated values from the literature. The enhanced conductivity is believed to be caused by structural changes close to the melting point which is not taken into account when extrapolating values from the literature. Experiments have been performed for the purpose of investigating the freezing of mixtures of n-alkanes in the C{sub 16}-C{sub 19} range. The positions of the solid-liquid interfaces have been measured as freezing occurred. Calculations of the ratio of liquid and solid conductivities show that the solid structure of mixtures of the investigated n-alkanes is predominantly in a rotator structure at the temperatures investigated. There are indications of a transformation into an orthorhombic structure at lower temperatures. The temperatures on the solid-liquid interface have been measured, and compared with calculated values from chapter 4. The temperature of the interface is represented better by the measured interfacial temperatures than by the calculated interfacial temperatures. The experimental results indicate that the diffusion of heat is the limiting mechanism of phase transition. This result in a homogeneous liquid composition. A numerical model has been developed in order to simulate the experimental freezing of mixtures. The model represents the results

  19. Solvation molar enthalpies and heat capacities of n-alkanes and n-alkylbenzenes on stationary phases of wide-ranging polarity.

    Science.gov (United States)

    Lebrón-Aguilar, Rosa; Quintanilla-López, Jesús Eduardo; Santiuste, José María

    2010-12-03

    A comparison of the most usual gas chromatographic methods for the calculation of partial molar enthalpies of solvation (Δ(sol)H(o)) has been carried out. Those methods based on the fitting of lnV(g) or ln(k/T) vs. 1/T and ln(k/T) vs. (1/T and the temperature arrangement, T(a)) are the most adequate ones for obtaining Δ(sol)H(o) values. However, the latter is the only reliable option for Δ(sol)H(o) estimation when commercial WCOT capillary columns are used, since in this case the estimation of some variables involved in the V(g) determination is less accurate or even impossible. Consequently, in this paper, Δ(sol)H(o) obtained from ln(k/T) vs. (1/T+T(a)) fitting at 373.15 and 298.15K for n-alkanes and n-alkylbenzenes on 12 commercial capillary columns coated with stationary phases covering the 203-3608 McReynolds polarity range are reported. Moreover, molar heat capacities of solvation at constant pressure (Δ(sol)C(p)(o)) have also been calculated using this method. A clear influence on Δ(sol)H(o) of the type and content of the substitution group in the stationary phase was observed. In addition, a linear relationship of Δ(sol)C(p)(o) with the van der Waals volume of the n-alkanes and the temperature gradient of density of the stationary phase was found. The effect of the size of the hydrocarbon on both thermodynamic variables was also investigated. Copyright © 2010 Elsevier B.V. All rights reserved.

  20. Effect of isothermal dilution on emission factors of organic carbon and n-alkanes in the particle and gas phases of diesel exhaust

    Science.gov (United States)

    Fujitani, Yuji; Saitoh, Katsumi; Fushimi, Akihiro; Takahashi, Katsuyuki; Hasegawa, Shuich; Tanabe, Kiyoshi; Kobayashi, Shinji; Furuyama, Akiko; Hirano, Seishiro; Takami, Akinori

    2012-11-01

    To investigate the effect of isothermal dilution (30 °C) on emission factors (EFs) of semivolatile and nonvolatile compounds of heavy-duty diesel exhaust, we measured EFs for particulate matter (PM), organic carbon (OC), and elemental carbon (EC) in the particle phase, and EFs for n-alkanes in both the particle phase and the gas phase of exhaust produced under high-idle engine operating conditions at dilution ratios (DRs) ranging from 8 to 1027. The EC EFs did not vary with DR, whereas the OC EFs in the particle phase determined at DR = 1027 were 13% of the EFs determined at DR = 8, owing to evaporation of organic compounds. Using partitioning theory and n-alkane EFs measured at DR = 14 and 238, we calculated the distributions of compounds between the particle and gas phases at DR = 1760, which corresponds to the DR for tailpipe emissions as they move from the tailpipe to the roadside atmosphere. The gas-phase EF of a compound with a vapor pressure of 10-7 Pa was 0.01 μg kg-1-fuel at DR = 14, and this value is 1/330 the value derived at DR = 1760. Our results suggest that the EFs of high-volatility compounds in the particle phase will be overestimated and that the EFs of low-volatility compounds in the gas phase will be underestimated if the estimates are derived from data obtained at the low DRs and they are applied to the real world. Therefore, extrapolation from EFs derived at low DR values to EFs at atmospherically relevant DRs will be a source of error in predictions of the concentrations of particulate matter and gas-phase precursors to secondary organic aerosols in air quality models.

  1. Gas chromatographic-mass spectrometric investigation of n-alkanes and carboxylic acids in bottom sediments of the northern Caspian Sea

    Science.gov (United States)

    Kenzhegaliev, Akimgali; Zhumagaliev, Sagat; Kenzhegalieva, Dina; Orazbayev, Batyr

    2018-03-01

    Prior to the start of experimental oil production in the Kashagan field (northern part of the Caspian Sea), n-alkanes and carboxylic acids contained in samples obtained from bottom sediments in the area of artificial island "D" were investigated by gas chromatography-mass spectrometry. Concentrations of 10 n-alkanes (composed of C10-C13, C15-C20) and 11 carboxylic acids (composed of C6-C12, C14-C16) were identified and measured. Concentrations of individual alkanes and carboxylic acids in bottom sediments of the various samples varied between 0.001 ÷ 0.88 μg/g and 0.001 ÷ 1.94 μg/g, respectively. Mass spectra, in particular the M+ molecular ion peak and the most intense peaks of fragment ions, are given. The present study illustrates the stability of molecular ions to electronic ionisation and the main fragment ions to the total ion current and shows that the initial fragmentation of alkanes implies radical cleavage of C2H5 rather than CH3. All aliphatic monocarboxylic acids studied were characterised by McLafferty rearrangement leading to the formation of F4 cation-radical with m/z 60 and F3 cation-radical with m/z 88 in the case of ethylhexanoic acid. The formation of oxonium ions presents another important aspect of acid fragmentation. Using mass numbers of oxonium ions and rearrangement ions allows determination of the substitution character in α- and β- C atoms. The essence of our approach is to estimate the infiltration of hydrocarbon fluids from the enclosing formation into sea water, comprising an analysis of derivatives of organic compounds in bottom sediments. Thus, concentrations of derived organic molecules can serve as a basis for estimates of the depth at which hydrocarbon fluids leak, i.e., to serve as an auxiliary technique in the search for hydrocarbon deposits and to repair well leaks.

  2. Determination of n-alkanes in C. annuum (bell pepper) fruit and seed using GC-MS: comparison of extraction methods and application to samples of different geographical origin

    NARCIS (Netherlands)

    de Rijke, E.; Fellner, C.; Westerveld, J.; Lopatka, M.; Cerli, C.; Kalbitz, K.; de Koster, C.G.

    2015-01-01

    An efficient extraction and analysis method was developed for the isolation and quantification of n-alkanes from bell peppers of different geographical locations. Five extraction techniques, i.e., accelerated solvent extraction (ASE), ball mill extraction, ultrasonication, rinsing, and shaking, were

  3. Hydrogen isotope ratios of terrestrial leaf wax n-alkanes from the Tibetan Plateau: Controls on apparent enrichment factors, effect of vapor sources and implication for altimetry

    Science.gov (United States)

    Zhang, Xiaolong; Xu, Baiqing; Günther, Franziska; Mügler, Ines; Lange, Markus; Zhao, Huabiao; Li, Jiule; Gleixner, Gerd

    2017-08-01

    Empirical evidence suggested that the altitudinal dependence of hydrogen isotope ratios of leaf wax n-alkanes (δDwax) can be used to estimate paleoaltitudinal changes. However, the application of δDwax-based paleoaltimetry remains difficult, as the impacts of evaporative, transpirative and biosynthetic processes on hydrogen isotope fractionations in changing environments and the influence of likely changing water vapor sources are not well explored. For this study, we sampled stream waters, soils and plant leaves along two transects spanning large gradients of altitude, precipitation amount, vapor source, temperature and vegetation type on the Tibetan Plateau (TP). δD values of stream water (as an approximation for δDp), soil water (δDsw) and plant leaf water (δDlw) as well as leaf wax n-alkanes were measured in order to quantify isotopic fractionations in the formation of leaf waxes. Most interestingly, we found a strong negative correlation between the evapotranspirative enrichment of leaf water against precipitation (εlw-p), which combines the effects of soil evaporation and leaf transpiration, and the biosynthetic hydrogen isotope fractionation (εwax-lw), which describes isotopic enrichment between leaf wax and leaf water. The relationship yields a steady apparent isotopic enrichment factor (εwax-p) between leaf wax and precipitation, which is independent from climatic parameters and has an average value of -107 ± 26‰ for grasses (monocotyledons) and -77 ± 22‰ for trees (dicotyledons). Since the terrestrial n-alkanes, especially n-C27 and n-C29, in sediments are derived from trees and grasses, the likely change of the vegetation type in the uplift of mountains can change the isotopic estimates by about ±30‰, which corresponds to an altitudinal change of ∼1600 m. We, therefore, suggest that hydrogen isotope ratio of sedimentary n-C31 alkane, which is mainly derived from grasses might be better proxies to reconstruct paleoaltitudes. Our large

  4. Digestibilidade determinada pelo método indireto usando o n-alcano C35 Digestibility determinate by indirect method using C35 n-alkane

    Directory of Open Access Journals (Sweden)

    Dimas Estrásulas de Oliveira

    2000-06-01

    Full Text Available Foi feito um trabalho de extração e análise de n-alcanos com o objetivo de investigar o uso do n-alcano (C35 presente nas forragens como um indicador interno para determinação de digestibilidade. Foram utilizadas amostras de experimentos de digestibilidade convencional realizados previamente entre os anos de 1978 e 1982. O C35 subestimou as digestibilidades da matéria seca e orgânica, apresentando diferença média, em relação ao método in vivo, de 4,68 (± 0,69 e 4,43 (± 0,85 unidades percentuais, respectivamente. O coeficiente de regressão não diferiu da unidade, indicando que os métodos foram equivalentes, havendo, porém, a necessidade de um fator de correção. Os coeficientes de correlação para a matéria seca e orgânica, observados entre os dois métodos, foram 0,87 e 0,85, respectivamente. O C35 apresentou recuperação fecal média de 91,76% (± 7,94, que contribuiu para o vício da técnica.An experiment was conducted, on extraction and analysis of n-alkanes, to investigate the use of n-alkane (C35 present in forages as an internal marker for the digestibility determination. Samples of forages and feces were taken from conventional digestibility trials, which were previous conducted from 1978 to 1982. The C35 underestimated the dry matter and organic matter digestibilities, presenting an average difference in relation to in vivo of 4.68 (± 0.69 and 4,43 (± 0.85 perceptual units, respectively. The coefficient of regression did not differ from the unit, indicating that both methods were equivalent, having, however, the necessity of a correction factor. The coefficients of correlation observed for the dry and organic matter between the two methods were 0.87 and 0.85, respectively. The average fecal recovery of C35 was 91.76% (± 7.94, and this contributed to the bias of the method.

  5. An instrument for the examination of nucleation from solution and its applications to the study of precipitation from diesel fuels and solutions of n-alkanes

    Energy Technology Data Exchange (ETDEWEB)

    Gerson, A R; Roberts, K J; Sherwood, J N [Strathclyde Univ., Glasgow (UK). Dept. of Pure and Applied Chemistry

    1991-03-01

    An automated apparatus has been designed and constructed to measure precipitation and dissolution of solids from solution at varying automatically predetermined rates of heating and cooling. The appearance and disappearance of crystals are detected by means of a fibre optic turbidity sensor attached to a Sybron/Brinkman colorimeter. Temperature is measured by a Pt resistance thermometer attached to a constant current source. Both of these measurements are recorded by a personal computer via an analog to digital converter. The temperature of the system and its variation is controlled from the personal computer via a digital to analog interface attached to the control head of a Haake F3Q cryostat. The system has been used for measurements of precipitation and dissolution temperatures for diesel waxes with and without nucleation additives. Studies have been made of the nucleation of a single n-alkane from solution. From these measurements, saturation curves, orders of reactions, interfacial tensions and the critical radii of nuclei can be assessed. (orig.).

  6. Bulk and compound-specific isotope analysis of long-chain n-alkanes from a 85,000 year sediment core from Lake Peten Petén Itzá, Guatemala

    Science.gov (United States)

    Mays, J.; Brenner, M.; Curtis, J. H.; Curtis, K.; Hodell, D. A.; Correa-Metrio, A.; Escobar, J.; Dutton, A. L.; Zimmerman, A. R.; Guilderson, T. P.

    2013-12-01

    Sediment core PI-6 from Lake Petén Itzá, Guatemala possesses an 85-ka record of climate from lowland Central America. Variations in sediment lithology suggest large, abrupt changes in precipitation during the last glacial and deglacial periods, and into the early Holocene. Study of cores from nearby Lake Quexil demonstrated the utility of using the carbon isotopic composition of leaf wax n-alkanes to infer changes in terrestrial vegetation (Huang et al. 2001). Forty-nine samples were taken from composite Petén Itzá core PI-6 to measure carbon isotopes of bulk organic carbon and long-chain n alkanes. Changes in δ13C values indicate shifts in the relative proportion of C3 to C4 biomass. The record shows largest δ13C variations are associated with Heinrich Events. Carbon isotope values in sediments deposited during the Last Glacial Maximum (LGM) indicate moderate precipitation and little rainfall fluctuation. The deglacial was a period of pronounced climate variability, e.g. the Bölling-Allerod and Younger Dryas. Arid times of the deglacial were inferred from samples with the greatest δ13C values in organic matter, reflecting the largest proportion of C4 plants. Such inferences are supported by stable isotope measurements on ostracod shells and analysis of pollen from the same sample depths in core PI-6. Carbon stable isotope measures on bulk organic carbon and n alkane compounds show similar trends throughout the record and the C:N ratio of Petén Itzá sediments indicates a predominantly allochthonous source for bulk organic matter. Hence, isotope measures on bulk organic carbon (δ13CTOC) in sediments from this lake are sufficient to infer climate-driven shifts in vegetation, making n-alkane extraction and isotope analysis superfluous.

  7. Hydrogen Apparent Fractionation between Precipitation and Leaf Wax n-Alkanes from Conifers and Deciduous Angiosperms along a Longitudinal Transect in Eurasia

    Science.gov (United States)

    Pedentchouk, Nikolai; Fisher, Katherine; Wagner, Thomas

    2010-05-01

    D/H composition of individual organic compounds derived from leaf wax may provide a wealth of information regarding plant-water relations in studies of plant ecology and climate change. Extracting that information from the organic D/H signal requires a thorough understanding of hydrogen isotope fractionation between environmental water and organic compounds. The purpose of this project is to investigate the importance of plant types and local climatic conditions on hydrogen apparent fractionation in higher terrestrial plants. We determined D/H composition of n-alkanes derived from leaf wax extracted from several extant plants representing common evergreen and deciduous conifer (Pinus and Larix) and deciduous angiosperm (Betula, Salix, and Sorbus) genera along a longitudinal transect from the UK to central Siberia at 10 different locations. These data were used to calculate the apparent fractionation factor (epsilon) between source water, estimated using the Online Isotopes in Precipitation Calculator, and n-alkanes. Our initial results show the following. First, we found large differences in the epsilon values among different genera at each location, e.g. Betula -63‰ vs. Salix -115‰ in Norwich, UK, and Betula -86‰ vs. Salix -146‰ in Novosibirsk, Russia. Assuming the plants at individual locations utilized soil water of very similar deltaD values, variations in the epsilon values are likely to be explained by differences in plant physiology and biochemistry. Second, we identified extensive shifts in the epsilon values in individual species along the transect from the UK to central Siberia, e.g. Betula -63‰ in Norwich vs. -104‰ in Zotino, Krasnoyarsk Krai, central Siberia and Salix -115‰ in Norwich vs. -164‰ in Sodankyla, Finland. With the exception of Sorbus, there is a positive relationship between the MAT (mean annual temperature) and epsilon values at locations above 2 °C MAT, suggesting a possible climatic effect on isotopic fractionation

  8. GC×GC measurements of C7-C11 aromatic and n-alkane hydrocarbons on Crete, in air from Eastern Europe during the MINOS campaign

    Directory of Open Access Journals (Sweden)

    X. Xu

    2003-01-01

    Full Text Available During the Mediterranean Intensive Oxidant Study (MINOS campaign in August 2001 gas-phase organic compounds were measured using comprehensive two-dimensional gas chromatography (GCxGC at the Finokalia ground station, Crete. In this paper, C7-C11 aromatic and n-alkane measurements are presented and interpreted. The mean mixing ratios of the hydrocarbons varied from 1±1 pptv (i-propylbenzene to 43±36 pptv (toluene. The observed mixing ratios showed strong day-to-day variations and generally higher levels during the first half of the campaign. Mean diel profiles showed maxima at local midnight and late morning, and minima in the early morning and evening. Results from analysis using a simplified box model suggest that both the chemical sink (i.e. reaction with OH and the variability of source strengths were the causes of the observed variations in hydrocarbon mixing ratios. The logarithms of hydrocarbon concentrations were negatively correlated with the OH concentrations integral over a day prior to the hydrocarbon measurements. Slopes of the regression lines derived from these correlations for different compounds are compared with literature rate constants for their reactions with OH. The slopes for most compounds agree reasonably well with the literature rate constants. A sequential reaction model has been applied to the interpretation of the relationship between ethylbenzene and two of its potential products, i.e. acetophenone and benzeneacetaldehyde. The model can explain the good correlation observed between [acetophenone]/[ethylbenzene] and [benzeneacetaldehyde]/[ethylbenzene]. The model results and field measurements suggest that the reactivity of benzeneacetaldehyde may lie between those of acetophenone and ethylbenzene and that the ratio between yields of acetophenone and benzeneacetaldehyde may be up to 28:1. Photochemical ages of trace gases sampled at Finokalia during the campaign are estimated using the sequential reaction model and

  9. GC×GC measurements of C7-C11 aromatic and n-alkane hydrocarbons on Crete, in air from Eastern Europe during the MINOS campaign

    Science.gov (United States)

    Xu, X.; Williams, C.; Plass-Dülmer, H.; Berresheim, H.; Salisbury, G.; Lange, L.; Lelieveld, J.

    2003-09-01

    During the Mediterranean Intensive Oxidant Study (MINOS) campaign in August 2001 gas-phase organic compounds were measured using comprehensive two-dimensional gas chromatography (GCxGC) at the Finokalia ground station, Crete. In this paper, C7-C11 aromatic and n-alkane measurements are presented and interpreted. The mean mixing ratios of the hydrocarbons varied from 1±1 pptv (i-propylbenzene) to 43±36 pptv (toluene). The observed mixing ratios showed strong day-to-day variations and generally higher levels during the first half of the campaign. Mean diel profiles showed maxima at local midnight and late morning, and minima in the early morning and evening. Results from analysis using a simplified box model suggest that both the chemical sink (i.e. reaction with OH) and the variability of source strengths were the causes of the observed variations in hydrocarbon mixing ratios. The logarithms of hydrocarbon concentrations were negatively correlated with the OH concentrations integral over a day prior to the hydrocarbon measurements. Slopes of the regression lines derived from these correlations for different compounds are compared with literature rate constants for their reactions with OH. The slopes for most compounds agree reasonably well with the literature rate constants. A sequential reaction model has been applied to the interpretation of the relationship between ethylbenzene and two of its potential products, i.e. acetophenone and benzeneacetaldehyde. The model can explain the good correlation observed between [acetophenone]/[ethylbenzene] and [benzeneacetaldehyde]/[ethylbenzene]. The model results and field measurements suggest that the reactivity of benzeneacetaldehyde may lie between those of acetophenone and ethylbenzene and that the ratio between yields of acetophenone and benzeneacetaldehyde may be up to 28:1. Photochemical ages of trace gases sampled at Finokalia during the campaign are estimated using the sequential reaction model and related data

  10. Ecological response to climate change and human activities indicated by n-alkane proxy during the mid- to late Holocene: a case study from an alpine lake

    Science.gov (United States)

    Zhang, C.; Zhao, C.

    2017-12-01

    Paleolimonological records provide long-term dynamics information of past climate, environment, human activities and ecological variations and give evolutionary perspectives to understand responses process of ecological shift to internal or external trigger. In this study, a powerful biomarkers, n-alkanes, was used to reconstruct the past 5000 years organic matter sources and ecological evolution history of Beilianchi Lake in the southwestern of Loess Plateau after preliminary investigation of modern samples. Climate-environment change and human activities were also traced by total organic matter (TOC), magnetic susceptibility (MS) and relevant proxies. The results showed that the ecosystem related to organic matter composition in Beilianchi Lake might be mainly controlled by climate change before 1400 cal B.P., whereas after that, it was significantly influenced by soil erosion induced by increasing population and enhanced human activities. Lake ecosystem experienced periodical change from relatively stable stage with combination of allochthonous-autochthonous organic sources prior to 1400 cal B.P. to extremely instability and final return to steady state with allochthonous-dominant organic source since 300 cal B.P.. During the period of instability, organic matter composition during 1400-800 cal B.P. indicated a obvious bimodal distribution based on probability density distribution analysis, which reflected the lake ecosystem might stay at bistable state and switched repeatedly from more-macrophytes state (regime A with low ACL) towards less-macrophytes state (regime B with high ACL) controlled by disturbance of soil erosion. The flickering during this period could serve as the early warning signal of transition towards more-macrophytes state or less-macrophytes state in lake ecosystems.

  11. Estimativa da ingestão e digestibilidade de erva e bolota em porcos alentejanos pela técnica dos n-alcanos Estimation of intake and digestibility of pasture and acorns by alentejano pigs using n-alkanes

    Directory of Open Access Journals (Sweden)

    C. Mendes

    2007-01-01

    Full Text Available Com o objectivo de estimar, em porcos Alentejanos, a ingestão e a digestibilidade de erva e bolota, foi realizado um ensaio utilizando n-alcanos de cadeia longa como marcadores fecais. Oito animais, alojados em caixas metabólicas, distribuídos aleatoriamente em 2 grupos de 4 animais cada, foram sujeitos a dois tratamentos. Cada animal do grupo 1 recebeu um bolinho por dia, contendo 100 mg de C32 e 150 mg de C36 e do grupo 2, dois bolinhos por dia contendo 50 mg de C32 e 75 mg de C36. Os animais foram alimentados com erva e bolota ao longo de todo o ensaio. A ingestão e a digestibilidade da dieta foram determinadas individualmente, através da medição das quantidades de alimento ingeridas e de fezes produzidas durante 5 dias e estimadas através da utilização da técnica dos n-alcanos. As estimativas da digestibilidade feitas através da utilização dos n-alcanos naturais C25 e C27 permitiram a obtenção de resultados muito próximos das medições in vivo. Os C29 e C31, em combinação com os nalcanos artificiais (C32 e C36, forneceram as estimativas da digestibilidade mais próximas da determinada, sendo os pares C29:C32 e C29:C36 os que forneceram as melhores estimativas para a ingestão. A administração dos C32 e C36 uma ou duas vezes por dia não demonstrou ter qualquer influência nas estimativas realizadas. A composição da dieta (bolota e erva, estimada pelos n-alcanos, apresentou valores próximos dos medidos in vivo, sendo as melhores estimativas dadas pelas combinações dos n-alcanos C29 e C31.The aim of this experiment was to estimate intake and digestibility of grass and acorns in Alentejano pigs, using long chain n-alkanes as fecal markers. Eight male Alentejano pigs, housed in metabolic cages were randomly allocated into two groups. Group 1 received one small cake per animal per day containing 100 mg of C32 and 150 mg of C36 and group 2 received two small cakes per animal per day containing 50 mg of C32 and 75 mg of C

  12. Abundance and diversity of n-alkane-degrading bacteria in a forest soil co-contaminated with hydrocarbons and metals: a molecular study on alkB homologous genes.

    Science.gov (United States)

    Pérez-de-Mora, Alfredo; Engel, Marion; Schloter, Michael

    2011-11-01

    Unraveling functional genes related to biodegradation of organic compounds has profoundly improved our understanding of biological remediation processes, yet the ecology of such genes is only poorly understood. We used a culture-independent approach to assess the abundance and diversity of bacteria catalyzing the degradation of n-alkanes with a chain length between C(5) and C(16) at a forest site co-contaminated with mineral oil hydrocarbons and metals for nearly 60 years. The alkB gene coding for a rubredoxin-dependent alkane monooxygenase enzyme involved in the initial activation step of aerobic aliphatic hydrocarbon metabolism was used as biomarker. Within the area of study, four different zones were evaluated: one highly contaminated, two intermediately contaminated, and a noncontaminated zone. Contaminant concentrations, hydrocarbon profiles, and soil microbial respiration and biomass were studied. Abundance of n-alkane-degrading bacteria was quantified via real-time PCR of alkB, whereas genetic diversity was examined using molecular fingerprints (T-RFLP) and clone libraries. Along the contamination plume, hydrocarbon profiles and increased respiration rates suggested on-going natural attenuation at the site. Gene copy numbers of alkB were similar in contaminated and control areas. However, T-RFLP-based fingerprints suggested lower diversity and evenness of the n-alkane-degrading bacterial community in the highly contaminated zone compared to the other areas; both diversity and evenness were negatively correlated with metal and hydrocarbon concentrations. Phylogenetic analysis of alkB denoted a shift of the hydrocarbon-degrading bacterial community from Gram-positive bacteria in the control zone (most similar to Mycobacterium and Nocardia types) to Gram-negative genotypes in the contaminated zones (Acinetobacter and alkB sequences with little similarity to those of known bacteria). Our results underscore a qualitative rather than a quantitative response of

  13. Bimolecular encounters and re-encounters (cage effect) of a spin-labeled analogue of cholestane in a series of n-alkanes: effect of anisotropic exchange integral.

    Science.gov (United States)

    Vandenberg, Andrew D; Bales, Barney L; Salikhov, K M; Peric, Miroslav

    2012-12-27

    Electron paramagnetic resonance (EPR) spectra of the nitroxide spin probe 3β-doxyl-5α-cholestane (CSL) are studied as functions of the molar concentration, c, and the temperature, T, in a series of n-alkanes. The results are compared with a similar study of a much smaller spin probe, perdeuterated 2,2,6,6-tetramethyl-4-oxopiperidine-1-oxyl (pDT). The Heisenberg spin exchange (HSE) rate constants, K(ex), of CSL are similar in hexane, octane, and decane and are about one-half of those for pDT in the same solvents. They are also about one-half of the Stokes-Einstein-Perrin prediction. This reduction in HSE efficiency is attributed to an effective steric factor, f(eff), which was evaluated by comparing the results with the Stokes-Einstein-Perrin prediction or with pDT, and it is equal to 0.49 ± 0.03, independent of temperature. The unpaired spin density in CSL is localized near one end of the long molecule, so the exchange integral, J, leading to HSE, is expected to be large in some collisions and small in others; thus, J is modeled by an ideal distribution of values of J = J(0) with probability f and J = 0 with probability (1 - f). Because of rotational and translation diffusion during contact and between re-encounters of the probe, the effective steric factor is predicted to be f(eff) = f(1/2). Estimating the fraction of the surface of CSL with rich spin density yields a theoretical estimate of f(eff) = 0.59 ± 0.08, in satisfactory agreement with experiment. HSE is well described by simple hydrodynamic theory, with only a small dependence on solvent-probe relative sizes at the same value of T/η, where η is the viscosity of the solvent. This result is probably due to a fortuitous interplay between long- and short-range effects that describe diffusion processes over relatively large distances. In contrast, dipole-dipole interactions (DD) as measured by the line broadening, B(dip), and the mean time between re-encounters within the cage, τ(RE), vary significantly

  14. Potencial discriminatório dos N-alcanos em plantas forrageiras tropicais por análises multivariadas Discriminatory potential of the N-alkanes in tropical forages by multivariate analysis

    Directory of Open Access Journals (Sweden)

    Cristiano Côrtes

    2005-08-01

    Full Text Available O potencial dos n-alcanos em discriminar frações ou espécies de gramíneas (Brachiaria brizantha Stapf. cv. Marandu, Cynodon dactylon Pers. cv. Coast-cross 1 e Panicum maximum Jacq. cv. Tanzânia 1 e leguminosas tropicais (Arachis pintoi Koprov & Gregory. cv. Amarillo e Glycine wightii Verdc. Soja Perene foi avaliado neste estudo. As forrageiras foram amostradas na primavera, no verão e inverno, com quatro repetições por espécie. Utilizaram-se nas análises os n-alcanos C24 a C35, sendo o C32 e C34 padrões internos. As concentrações dos n-alcanos nas diferentes espécies e respectivas frações (lâminas foliares, haste porções superior e inferior e matéria morta, para gramíneas; folhas, caule porções superior e inferior e matéria morta para leguminosas foram avaliadas mediante análises multivariadas. O potencial discriminatório dos n-alcanos foi determinado pela análise de variáveis canônicas. As espécies e frações foram divididas em grupos por meio da análise de agrupamento. Os alcanos com menor potencial discriminatório foram: C26, C29, C25, C27 e C28 (primavera, C26, C28, C27, C30 e C29 (verão e C28, C26, C25, C29 e C27 (inverno. Nos períodos de primavera e inverno, a técnica de n-alcanos permitiu distinguir a lâmina foliar do coastcross das hastes superior e inferior, bem como das gramíneas e leguminosas. Em pastagens exclusivas de Brachiaria brizantha, no período de verão, seria possível discriminar as frações de importância nutricional, lâmina foliar e haste superior, pela determinação dos n-alcanos. As análises multivariadas, as variáveis canônicas e a análise de agrupamento representam boas alternativas de cálculo para melhorar a aplicabilidade da técnica dos n-alcanos na discriminação das dietas de herbívoros.The discriminatory potential of n-alkanes in tropical grasses (Brachiaria brizantha Stapf. cv. Marandu, Cynodon dactylon Pers. cv. Coast-cross 1 and Panicum maximum Jacq. cv. Tanz

  15. Secretive production of long-chain fatty acids, triacylglycerols and n-alkane-2-ones by fermentation processes; Hakkoho ni yoru ekitai nenryo no seisan wa kanoka (shishitsu no bunpi seisan)

    Energy Technology Data Exchange (ETDEWEB)

    Fukui, S. [University of Fukuyama, Hiroshima (Japan). Faculty of Engineering

    1995-10-20

    Secretive production of lipids, which are useful source for engine-driving fuel, by microbial process using carbohydrate biomasses as substrate has been investigated in our laboratory. This review consists of four parts concerning breedings and selection of lipid-secretive microorganisms : (1) breedings of long-chain fatty acid-secretive strains from Candida lipolytica L-1 by a step-wise mutagenesis process, (2) selection of a triacylglycerol (TG)-secretive and accumulative yeast strain Trichosporon sp. SH45Y, (3) breedings of mutants, SH45Y-derivatieves, having potent ability to produce TG secretively from glucose, a typical biomass charbohydrate, and (4) selection of microorganisms which produce liquid-n-alkane in culture medium by utilizing long-chain fatty acids and TG; a strain of Penicillium decumbens can produce liquid alkalis with a yield of approximately 60 % in weight from palm kernel oil, a commercial TG. 10 refs., 7 figs., 7 tabs.

  16. Structure and phase transitions of monolayers of intermediate-length n-alkanes on graphite studied by neutron diffraction and molecular dynamics simulation

    DEFF Research Database (Denmark)

    Diama, A.; Matthies, B.; Herwig, K. W.

    2009-01-01

    measurements indicate that the two monolayer films differ principally in the transition temperatures between phases. At the lowest temperatures, both C24 and C32 form a crystalline monolayer phase with a rectangular-centered (RC) structure. The two sublattices of the RC structure each consists of parallel rows...... show evidence of broadening of the lamella boundaries as a result of molecules diffusing parallel to their long axis. At still higher temperatures, they indicate that the introduction of gauche defects into the alkane chains drives a melting transition to a monolayer fluid phase as reported previously...

  17. Long n-alkanes isomerization by medium pore zeolites with pore mouth and key lock mechanisms; Isomerisation des paraffines longues par des zeolithes a pores moyens selon les mecanismes ouverture de pore et cle serrure

    Energy Technology Data Exchange (ETDEWEB)

    Claude, M.

    1999-10-01

    Skeletal isomerization of long n-alkanes is practiced to improve cold flow properties of diesel and lubricant fractions. In this work, model long n-alkanes (n-C{sub 10} - n-C{sub 24}) were hydro-isomerized in a fixed bed down flow vapour phase reactor loaded with bifunctional Pt/H-ZSM-22 zeolite catalyst. The skeletal isomers were analysed and identified with GC/MS. High isomer yields were obtained. The distribution of positional mono-methyl-branched isomers obtained from n-C{sub 12} to n-C{sub 24} are typically bimodal. This is explained by adsorption and reaction of the alkanes in pore mouths and locks on the external surface of the zeolite crystals. The pore mouth mode favours branching at C{sub 2} and C{sub 3}. The 'key lock' type proceeds by penetration of the two ends of the hydrocarbon chain into a different pore opening and favours more central mono-branching of the chain. The contribution of the key lock mode increases with increasing chain length and with the reaction temperature. The preferentially formed dimethyl-branched isomers have a separation between branchings of three up to fourteen carbon atoms. The formation of the second methyl-branching occurs preferentially from a centrally branched mono-methyl-branched isomer, so that the second branching is generated always more toward the end of the chain. Owing to the differences in adsorption entropy among the locks, at higher temperatures the largest lock is preferred and the distance between the two branching along the carbon chain in the preferred isomers is biggest. Thus the work resulted in the formulation of structure-selectivity relationships. n-C{sub 18} was hydro-isomerized on other zeolites. The nature and distribution of the isomers obtained suggest that the tubular 10-ring zeolites ZSM-23, ZSM-35 and SAPO-11 also operate according to pore mouth and key lock concepts. Zeolites with 12-rings show typical product patterns for catalysis in absence of steric hindrance. (author)

  18. Excess molar volumes and dynamic viscosities for binary mixtures of toluene + n-alkanes (C5-C10) at T = 298.15 K - Comparison with Prigogine-Flory-Patterson theory

    International Nuclear Information System (INIS)

    Iloukhani, Hossein; Rezaei-Sameti, Mahdi; Basiri-Parsa, Jalal

    2006-01-01

    Densities ρ, dynamic viscosities η, for binary mixtures of toluene with some n-alkanes, namely, n-pentane, n-hexane, n-heptane, n-octane, n-nonane, and n-decane have been measured over the complete composition range. Excess molar volumes V E , viscosity deviations Δη, and excess Gibbs free energy of activation ΔG * E , were calculated there from and were correlated by Redlich-Kister type function in terms of mole fractions. For mixtures of toluene with n-pentane and n-hexane the V E is negative and for the remaining systems is positive. The Δη values are negative for all the studied mixtures. The ΔG * E values shows the positive values for the binary mixtures with n-decane, whereas the negative values have been observed for all the remaining binary mixtures. From the results, the excess thermal expansivities at constant pressure α E , is also estimated. The Prigogine-Flory-Patterson (PFP) theory and its applicability in predicting V E is tested. The results obtained for viscosity of binary mixtures were used to test the semi-empirical relations of Grunberg and Nissan, Tamura and Kurata, Hind et al., Katti and Chaudhri, McAllister, Heric, Kendall, and Monroe. The experimental on the constituted binaries are analyzed to discus the nature and strength of intermolecular interactions in these mixtures

  19. Integrated Use of n-Alkanes and PAH to Evaluate the Anthropogenic Hydrocarbon Sources and the Toxicity Assessment of Surface Sediments from the Southwestern Coasts of the Caspian Sea

    Directory of Open Access Journals (Sweden)

    Golshan Shirneshan

    2017-07-01

    Full Text Available Polycyclic aromatic hydrocarbon (PAH compounds and normal alkanes form a large group of undegradable environmental contaminats. This study aims to determine the sources and distribution of oil pollution (PAH compounds and normal alkanes in the sediments of the southwestern coastal areas of the Caspian Sea and to compare their levels with the relevant standards. For this purpose, 18 surface sediment samples were collected from depths of 10, 20, and 50 meters along two transects in the vertical direction located in the coastal areas of Sangachin and Hashtpar (Gilan Province. The samples were then examined using mass-spectrometric gas chromatography. The origins of n-alkanes were identified using CPI index (0.76-0.95, U/R (3.30‒6.57, and Pristane/Phytane (0.21‒0.42. The sources of PAHs were determined using the index ratios of LMW/HMW (1.93‒13.37, Phenanthrene/Anthracene (11.44‒ 16.7, Chrysene/Benzo (a anthracene (4.69‒10/33, Fluoranthene/Pyrene (0.53‒0.69, and MP/P (0.05‒0.08. Results confirmed the dominant petrogenic source of the hydrocarbons found in the region. The total concentrations of 30 aliphatic hydrocarbons and PAHs in the sediments ranged from 823.8 to 3899.5 µg/g and from 626.95 to 3842.5362 ng/g, respectively. Comparison of the measured PAH concentrations with US sediment quality guidelines revealed that the levels of naphthalene, fluorine, Acenaphthylene, and Acenaphthene exceeded the ERLs at stations with depths of 50m in Sangachin and Hashtpar while comparisons with Canadian standards indicated that they were higher than PELs at all the stations sampled. A major point of great concern is the high concentration of naphthalene as the most toxic PAH compound, which naturally warrants due attention to adopt appropriate management programs.

  20. Optimized cleanup method for the determination of short chain polychlorinated n-alkanes in sediments by high resolution gas chromatography/electron capture negative ion-low resolution mass spectrometry

    International Nuclear Information System (INIS)

    Gao Yuan; Zhang Haijun; Chen Jiping; Zhang Qing; Tian Yuzeng; Qi Peipei; Yu Zhengkun

    2011-01-01

    Graphical abstract: The sediment sample could be purified by the optimized cleanup method, and satisfying cleanup efficiency was obtained. Highlights: → The elution characters of sPCAs and interfering substances were evaluated on three adsorbents. → An optimized cleanup method was developed for sPCAs with satisfying cleanup efficiency. → The cleanup method combined with HRGC/ECNI-LRMS was applied for sPCAs analysis. → The sPCAs levels range from 53.6 ng g -1 to 289.3 ng g -1 in tested sediment samples. - Abstract: The performances of three adsorbents, i.e. silica gel, neutral and basic alumina, in the separation of short chain polychlorinated n-alkanes (sPCAs) from potential interfering substances such as polychlorinated biphenyls (PCBs) and organochlorine pesticides were evaluated. To increase the cleanup efficiency, a two-step cleanup method using silica gel column and subsequent basic alumina column was developed. All the PCB and organochlorine pesticides could be removed by this cleanup method. The very satisfying cleanup efficiency of sPCAs has been achieved and the recovery in the cleanup method reached 92.7%. The method detection limit (MDL) for sPCAs in sediments was determined to be 14 ng g -1 . Relative standard deviation (R.S.D.) of 5.3% was obtained for the mass fraction of sPCAs by analyzing four replicates of a spiked sediment sample. High resolution gas chromatography/electron capture negative ion-low resolution mass spectrometry (HRGC/ECNI-LRMS) was used for sPCAs quantification by monitoring [M-HCl]· - ions. When applied to the sediment samples from the mouth of the Daliao River, the optimized cleanup method in conjunction with HRGC/ECNI-LRMS allowed for highly selective identifications for sPCAs. The sPCAs levels in sediment samples are reported to range from 53.6 ng g -1 to 289.3 ng g -1 . C 10 - and C 11 -PCAs are the dominant residue in most of investigated sediment samples.

  1. Perfil de n-alcanos em cinco espécies de plantas forrageiras tropicais - DOI: 10.4025/actascianimsci.v27i3.1207 Profile of n-alkanes in five species of plants tropical forages - DOI: 10.4025/actascianimsci.v27i3.1207

    Directory of Open Access Journals (Sweden)

    Antônio Ferriani Branco

    2005-03-01

    Full Text Available O objetivo do experimento foi estudar o perfil de n-alcanos em espécies de gramíneas (Brachiaria brizantha, Cynodon dactylon e Panicum maximum e leguminosas (Arachis pintoi e Glycine wightii. Foram identificados e quantificados por meio de cromatografia gasosa, os n-alcanos C24 a C35, sendo C32 e C34 padrões internos. As concentrações dos n-alcanos nas diferentes espécies e respectivas frações (lâminas foliares, colmos porções superior e inferior e matéria morta para gramíneas; folhas, caule porção superior e inferior e matéria morta para leguminosas foram submetidas à análise de variância e teste de média (Tukey. Nos períodos de primavera e inverno, para a maioria das espécies e frações, há predomínio dos n-alcanos de cadeia ímpar. Houve maior concentração de C29, C31 e C33 na primavera, C27, C28, C29, C30 e C31, no verão e C27, C29, C31 e C33 no invernoThis experiment aimed to study the profile of n-alkanes in tropical grasses species (Brachiaria brizantha, Cynodon dactylon and Panicum maximum and legumes (Arachis pintoi and Glycine wightii. They were identified and quantified, through gas cromatography, the n-alkanes C24 to C35, being the alkanes C32 and C34 internal indices. The n-alkanes concentrations in the different species and respective fractions (leaf blade, stem higher and lower portion and dead matter for grasses; leaves, stem higher portion, stem lower portion and dead matter for legumes were submitted to variance analysis and mean test (Tukey. For most of the species and fractions, there is prevalence of odd chain n-alkanes during springtime and winter. There was larger concentration of the alkanes C29, C31 and C33 in springtime, C27, C28, C29, C30 and C31 in summer and C27, C29, C31 and C33 in winter

  2. Uso de N-alcanos na estimativa da composição botânica em amostras com diferentes proporções de Brachiaria brizantha e Arachis pintoi Use of N-alkanes for estimations of botanical composition in samples with different proportions of Brachiaria brizantha and Arachis pintoi

    Directory of Open Access Journals (Sweden)

    Cristiano Côrtes

    2005-10-01

    Full Text Available Este trabalho foi conduzido para se determinar a composição de n-alcanos (C24 a C36 em diferentes proporções de dietas hipotéticas de Brachiaria brizantha Stapf. cv. Marandu e Arachis pintoi Koprov & Gregory. cv. Amarillo (0; 15; 30; 45; 60 e 100% de Arachis pintoi e identificar a combinação de alcanos que permite calcular a composição botânica de dietas com o menor valor residual (real menos o estimado. As forragens foram amostradas no verão e os n-alcanos extraídos pelo método de saponificação direta, sendo identificados e quantificados por meio de análise de cromatografia gasosa. O alcano C34 foi utilizado como padrão interno. As proporções de A. pintoi nas dietas foram estimadas pela minimização do z (soma dos quadrados dos desvios entre a proporção real dos alcanos analisados e as proporções pré-estabelecidas (tratamentos, utilizando-se a equação de Duncan et al. (1999. Observou-se que houve predomínio das cadeias carbônicas ímpares e que a concentração total de n-alcanos decresceu à medida que se aumentou a proporção de A. pintoi nos tratamentos. Estimativas acuradas da composição botânica de misturas de A. pintoi com B. brizantha foram obtidas utilizando-se os alcanos C29, C31, C33 e C35. O alcano C35 foi fundamental para a qualidade das estimativas. Os resultados indicaram o grande potencial da técnica para estudos com animais em pastejo.This trial was carried out to determine the composition of n-alkanes (C24 to C36 in hypothetical diets comprising of pure Brachiaria brizantha Stapf. cv. Marandu and Arachis pintoi Koprov & Gregory. cv. Amarillo and mixtures of these two spececies with 15%, 30%, 45%, or 60% of Arachis pintoi; it also intended to identify the combination of alkanes that allows to calculate the botanical composition of diets with the smallest residual value (real less estimated values. The forages were sampled in the summer. The n-alkanes were extracted for the direct saponification

  3. Comparative study of normal and branched alkane monolayer films adsorbed on a solid surface. I. Structure

    DEFF Research Database (Denmark)

    Enevoldsen, Ann Dorrit; Hansen, Flemming Yssing; Diama, A.

    2007-01-01

    their backbone and squalane has, in addition, six methyl side groups. Upon adsorption, there are significant differences as well as similarities in the behavior of these molecular films. Both molecules form ordered structures at low temperatures; however, while the melting point of the two-dimensional (2D......The structure of a monolayer film of the branched alkane squalane (C30H62) adsorbed on graphite has been studied by neutron diffraction and molecular dynamics (MD) simulations and compared with a similar study of the n-alkane tetracosane (n-C24H52). Both molecules have 24 carbon atoms along...... temperature. The neutron diffraction data show that the translational order in the squalane monolayer is significantly less than in the tetracosane monolayer. The authors' MD simulations suggest that this is caused by a distortion of the squalane molecules upon adsorption on the graphite surface. When...

  4. Uso de n-alcanos na estimativa da composição botânica da dieta em ovinos alimentados com diferentes proporções de Brachiaria decumbens Stapf e Arachis pintoi Koprov e Gregory Use of n-alkanes to estimate the dietary botanical composition in sheep fed different proportions of Brachiaria decumbens Stapf and Arachis pintoi Koprov and Gregory

    Directory of Open Access Journals (Sweden)

    Nelson Massaru Fukumoto

    2007-08-01

    Full Text Available Neste experimento objetivou-se avaliar o poder discriminatório dos n-alcanos para estimar com acurácia e precisão a composição botânica da dieta em ovinos alimentados com diferentes proporções de Arachis pintoi Koprov & Gregory cv. Amarillo (0, 15, 30, 45 e 60% e Brachiaria decumbens Stapf. Foram utilizados 20 ovinos em delineamento inteiramente casualizado, com período experimental de dez dias de adaptação à dieta e cinco dias de coleta de fezes. Nas amostras (compostas de fezes do período e nos fenos, foi analisada a concentração de n-alcanos. Para o cálculo da composição botânica, utilizou-se minimização da soma dos quadrados dos desvios, considerando as concentrações dos alcanos nos componentes da dieta e nas fezes. Para a escolha dos alcanos mais discriminatórios, foram utilizadas as análises multivariadas e as variáveis canônicas. As estimativas calculadas foram submetidas à análise de variância. As médias foram comparadas pelo teste t e as correções dos valores estimados em relação aos valores reais foram ajustadas em regressão linear. As variáveis canônicas indicaram que os alcanos C35, C33, C30, C31, C27, C29 e C36 são os de maior potencial discriminatório. O uso desses alcanos nos cálculos foi mais acurado e preciso para estimar a proporção de A. pintoi na dieta que o uso de apenas dois ou três alcanos com poder discriminatório. O melhor ajuste da regressão também foi encontrado para esses alcanos. O teste t para o intercepto da equação (a e o coeficiente de regressão (b indicaram que a = 0 e b = 1, comprovando que os valores estimados são equivalentes aos valores reais. As análises multivariadas mostraram-se ferramentas de grande importância na escolha dos n-alcanos nos cálculos nas estimativas.The objective of this experiment was to use n-alkane to estimate accurately and precisely the botanical composition of dietary forage in sheep fed different proportions of Arachis pintoi

  5. Thermodynamic parameters for the adsorption of volatile n-alkane ...

    African Journals Online (AJOL)

    alkanes hexane to nonane on ground dried water hyacinth (E. crassipes) root biomass were studied between 40 and 70°C column temperature using inverse gas chromatography, before and after treatment of the root biomass with mineral acid ...

  6. n-Alkanes in surficial sediments of Visakhapatnam harbour, east ...

    Indian Academy of Sciences (India)

    Visakhapatnam harbour, a semi-enclosed water body is one of the .... PDB − 1. } × 1000. 2.5 Extraction of lipids. Total lipids (TL) were extracted from lyophilized sediments following ..... 2010 Sources of OM and microbial community structure.

  7. Distribution and congener profiles of short-chain chlorinated paraffins in indoor/outdoor glass window surface films and their film-air partitioning in Beijing, China.

    Science.gov (United States)

    Gao, Wei; Wu, Jing; Wang, Yawei; Jiang, Guibin

    2016-02-01

    Short-chain chlorinated paraffins (SCCPs) are a group of n-alkanes with carbon chain length of 10-13. In this work, paired indoor/outdoor samples of organic films on window glass surfaces from urban buildings in Beijing, China, were collected to measure the concentrations and congener distributions of SCCPs. The total SCCP levels ranged from 337 ng/m(2) to 114 μg/m(2), with total organic carbon (TOC) normalized concentrations of 365 μg/m(2)-365 mg/m(2). Overall, the concentrations of SCCPs on the interior films were higher than the concentrations on the exterior films, suggesting an important indoor environmental exposure of SCCPs to the general public. A significant linear relationship was found between the SCCP concentrations and TOC, with a correlation coefficient of R = 0.34 (p film-air partitioning model suggests that the indoor gas-phase SCCPs are related to their corresponding window film levels. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Consumo e digestibilidade da matéria seca de fenos de braquiária decumbens e amendoim forrageiro em ovinos estimados por meio de n-alcanos Use of n-alkanes to estimate intake and digestibility of signalgrass and forage peanut in sheep

    Directory of Open Access Journals (Sweden)

    Nelson Massaru Fukumoto

    2007-04-01

    Full Text Available O experimento foi realizado com os objetivos de avaliar a técnica de n-alcanos para estimar o consumo e a digestibilidade da MS em ovinos e definir a estratégia de coleta de fezes e os alcanos internos a serem utilizados no cálculos. Vinte ovinos foram distribuídos em delineamento inteiramente casualizado e alimentados com dietas formuladas com diferentes proporções de amendoim forrageiro (Arachis pintoi Koprov & Gregory cv. Amarillo e braquiária decumbens [Urochloa decumbens (Stapf, Webster] (0, 15, 30, 45 e 60% de amendoim forrageiro, base da MS. O período experimental teve duração de 18 dias, dez de adaptação à dieta, três para administração do indicador externo (C32 em péletes de celulose e cinco de coleta de fezes. As fezes foram coletadas seis vezes ao dia (9, 13, 17, 21, 1 e 5h, diretamente no reto do animal. Os dados foram submetidos à análise de variância e as comparações das médias estimadas aos valores reais foram feitas utilizando-se o teste t a 5% de significância. Para determinação da digestibilidade aparente da MS, os animais foram equipados com bolsas coletoras de fezes. O consumo foi calculado utilizando-se os alcanos internos C31 e C33 isoladamente ou em conjunto. Para o cálculo da digestibilidade da MS, foram utilizados os alcanos internos C33 a C35. Para obtenção de estimativas adequadas de digestibilidade, é necessária a correção para os valores de recuperação fecal dos indicadores internos, observando-se que os melhores resultados foram obtidos quando se utilizou o alcano interno C33 nos cálculos. Para estimar o consumo de MS, devem-se utilizar, de forma conjunta nos cálculos, os alcanos internos C31 e C33, sem necessidade de correção para recuperação fecal, podendo-se coletar uma única amostra de fezes por animal por dia, pela manhã (9 h ou à tarde (13 h.The objective of this trial was to use n-alkanes to estimate dry matter intake (DMI and DM digestibility in sheep. It was also

  9. Film Reviews.

    Science.gov (United States)

    Lance, Larry M.; Atwater, Lynn

    1987-01-01

    Reviews four Human Sexuality films and videos. These are: "Personal Decisions" (Planned Parenthood Federation of America, 1985); "The Touch Film" (Sterling Production, 1986); "Rethinking Rape" (Film Distribution Center, 1985); "Not A Love Story" (National Film Board of Canada, 1981). (AEM)

  10. Depletion of compounds from thin oil films in seawater

    International Nuclear Information System (INIS)

    Brakstad, O.G.; Faksness, L.G.; Melbye, A.G.

    2002-01-01

    When oil is spilled on water, the oil compounds distribute between droplets and water-soluble phases in the water column. Some small organic acids, phenols, BTEX, and aromatic compounds will dissolve completely, but larger polycyclic aromatic hydrocarbons (PAH) and alkanes will remain in the droplet fraction. The biodegradation of droplets occurs at the oil-water interface. A method for immobilizing the oil films onto hydrophobic surfaces was developed in order to obtain a stable oil surface during the biodegradation period. A test system was also established to determine the depletion of oil compounds from the oil phase, including both abiotic and biotic processes. Three North Sea oils were used in the study. Two were paraffinic oils rich in n-alkanes and aromatic compounds, and one was asphalthenic which was richer in branched alkanes and PAH. The biodegradation period was 2 months at 13 degrees C. Samples from the water and thin film on the fabric was analyzed for carbon 10 and carbon 36 by gas chromatography-flame ionization detection. Semi-volatile organic compounds were analyzed using gas chromatography-mass spectrometry. Results indicated that the depletion process for alkanes was completely caused by biodegradation, while aromatic compounds were depleted by abiotic dissolution as well as by biodegradation. The system has potential for determining oil depletion processes under controlled surface-to-volume conditions, such as thin oil films and dispersed oil droplets. In addition, the system can be used to determine the depletion process in flow-through systems. 13 refs., 3 tabs., 9 figs

  11. Study of the role of film flows in three-phase displacement mechanisms in porous media; Etude du role des ecoulements par film dans les mecanismes de deplacement triphasique en milieux poreux

    Energy Technology Data Exchange (ETDEWEB)

    Bataillon, D

    1996-12-11

    The determination of the role of liquid films in three phase flows in porous media is very important for enhanced oil recovery by gas injection in a petroleum reservoir. The existence of liquid films (water, oil), their thickness and their stability, control the distribution of fluids and the displacement of these fluids in the reservoir. The target of this research is to obtain, from experimental observations, the microscopic rules of flow by films taking into account the elementary mechanisms controlling the displacement of fluids. For this, a method of liquid film flow thickness measurement is developed in a quartz Hele-Shaw cell. It is based on infrared spectrometry, used for the first time to our knowledge for such an application, which gives the possibility to follow the drainage kinetics of oil and water in the presence of gas. When the thick oil film is initially stable on water in the presence of gas, it slowly drains until it reaches a constant thickness of about 20 nm. This film may breaks down into micro droplets of less than few micrometers in diameter. When this thick oil film is not initially stable, it immediately breaks down into droplets of 10 to 20 {mu}m in diameter prevents any oil flow. For spreading conditions, the initial oil thickness of about 200 nm is calculated form the Ca capillary number. The flow kinetics of this film is then determined when macroscopic forces are predominant. Finally, for the estimation of the stabilisation thickness, disjoining pressure isotherms, based on long-scale intermolecular forces (VdW), are calculated for pure n-alkanes. In order to study the macroscopic flow parameters, gravity drainage experiments are carried out in a 2D glass network (micro-model). Measurements of oil production (weight) and residual saturations (image analysis) show clearly the influence of the initial stability of oil, coating water in the presence of gas, on the flow mechanisms. (author) 73 refs.

  12. Thermodynamic and kinetic anisotropies in octane thin films.

    Science.gov (United States)

    Haji-Akbari, Amir; Debenedetti, Pablo G

    2015-12-07

    structure calculations, and observe no noticeable difference between the free surface and the bulk in efficiently exploring the potential energy landscape. This is unlike the films of model atomic glass formers that tend to sample their respective landscape more efficiently at free surfaces. We discuss the implications of this finding to the ability of octane-and other n-alkanes-to form ultrastable glasses.

  13. Thin films

    International Nuclear Information System (INIS)

    Strongin, M.; Miller, D.L.

    1976-01-01

    This article reviews the phenomena that occur in films from the point of view of a solid state physicist. Films form the basis for many established and developing technologies. Metal layers have always been important for optical coatings and as protective coatings. In the most sophisticated cases, films and their interaction on silicon surfaces form the basis of modern electronic technology. Films of silicon, GaAs and composites of these materials promise to lead to practical photovoltaic devices

  14. Nuclear films

    International Nuclear Information System (INIS)

    Malone, Peter.

    1985-01-01

    This booklet is a resource for the study of feature films that highlight the theme of nuclear war. It provides basic credits and brief indication of the theme, treatment, quality and particular notable aspects; and a series of questions raised by the film. Seventy feature films and thirty documentaries are examined

  15. Film processing

    International Nuclear Information System (INIS)

    Abdul Nassir Ibrahim; Azali Muhammad; Ab. Razak Hamzah; Abd. Aziz Mohamed; Mohamad Pauzi Ismail

    2008-01-01

    The processing was made not only to show what are in the film but also to produce radiograph with high quality where the information gathered really presented level of the quality of the object inspected. Besides that, good procedure will make the film with good quality can keep the film in long time for reference. Here, more detailed on how the dark room functioned and its design. So, the good procedure while processed the film will be discussed detailed in this chapter from entering the dark room to exit from there.

  16. Demens Film

    DEFF Research Database (Denmark)

    Jensen, Anders Møller

    2012-01-01

    Vi vil skabe film til mennesker med demens – ikke film om demens sygdommen eller beretninger om livet og hverdagen med en kronisk lidelse. Filmene skal medvirke til at frembringe en behagelig stemning omkring og hos mennesker med demens, så hverdagen bliver så tryg som mulig. Filmene skal samtidig...... var at afgrænse og prioritere projektet, samt komme med anbefalinger omkring hvad der er vigtigt, i forbindelse med produktion af film målrettet mennesker med demens. Resultat af ekspertgruppen sammenfattes i denne rapport. Projektet gennemføres som et samarbejde mellem Retrospect Film...

  17. thin films

    Indian Academy of Sciences (India)

    microscopy (SEM) studies, respectively. The Fourier transform ... Thin films; chemical synthesis; hydrous tin oxide; FTIR; electrical properties. 1. Introduction ... dehydrogenation of organic compounds (Hattori et al 1987). .... SEM images of (a) bare stainless steel and (b) SnO2:H2O thin film on stainless steel substrate at a ...

  18. Into films

    DEFF Research Database (Denmark)

    Tan, Ed S.; Doicaru, Miruna M.; Hakemulder, Frank

    2017-01-01

    Most film viewers know the experience of being deeply absorbed in the story of a popular film. It seems that at such moments they lose awareness of watching a movie. And yet it is highly unlikely that they completely ignore the fact that they watch a narrative and technological construction. Perh...

  19. Catalytic behavior of Pt nanoparticles dealuminated Y-zeolite for some n-alkane hydroisomerization

    Directory of Open Access Journals (Sweden)

    S.A. Hanafi

    2014-06-01

    Full Text Available Dealuminated zeolite Y-supported platinum was prepared adopting two dealumination methods, viz. fast (1, 3 and 6 h and slow method (18 h. The content of Pt was constant at 0.5 wt% in all investigated catalysts. The prepared samples were characterized using TGA/DSC, XRD, FTIR techniques, nitrogen adsorption at −196 °C and TEM-connected with energy dispersive spectroscopy (EDS. Surface acidity was investigated via pyridine adsorption using FT-IR spectroscopy. The parent and dealuminated Y-zeolite samples were characterized by their microporous system. By increasing the dealumination time to 6 h, the increased specific surface area and total pore volume indicated a sort of pore opening taking place with an increase in the accessibility of nitrogen molecules. DSC confirmed the thermal stability of the dealuminated zeolite samples up to 800 °C. The prepared catalysts were tested through hydroisomerization reactions of n-hexane and n-heptane using a micro-catalytic pulse technique. Different catalytic behaviors could be distinguished for the dealuminated samples based on competitive reactions; hydro-isomerization, hydrocracking and cyclization. Slow dealumination leads to the most selective catalysts for hydroisomerization. n-Heptane was converted to higher extent than n-hexane; cracking process was more evident when the former was fed to the reactor.

  20. Inelastic neutron scattering study on the polytypism of even-numbered n-alkanes

    Science.gov (United States)

    Kubota, Hideki; Kaneko, Fumitoshi; Kawaguchi, Tatsuya

    2005-02-01

    The thermodynamic properties of the two polytypes of n-hexatriacontane ( n- C36H74), single-layered structure Mon and double-layered structure Orth II, have been studied with incoherent inelastic neutron scattering and solubility measurements. The solubility measurements show that Orth II is more stable than Mon, because of its larger entropy. The neutron scattering measurements reveal that the vibrational modes of Orth II shift to the lower frequencies compared with those of Mon in the frequency region below 120 cm-1. The vibrational modes in this region make a dominant contribution to the vibrational entropy of a system, and the advantage of Orth II in vibrational entropy due to the low-frequency shifts is estimated to be 7.8 J K-1 mol-1 at 288 K under the harmonic approximation, which is in good agreement with the entropy difference between Mon and Orth II determined by solubility measurements. These results suggest that the relative stability of polytypic structures of long-chain compounds is mainly determined by the vibrational entropy of the low-frequency modes.

  1. Application of the N-Alkane molecular alloys to thermally protected containers for catering

    Directory of Open Access Journals (Sweden)

    Arjona, F.

    2000-08-01

    Full Text Available A thermally controlled transport device was designed and tested. As hot food needs to be transported at temperatures between 60 and 70ºC in order to avoid contamination by microorganisms, the use of Molecular Alloy Phase Change Materials (MAPCM can lead to improvements in this field of application. A heat transfer numerical simulation of the box used for transporting the food was conducted. Despite obvious simplifications, a good agreement between numerical simulation and experimental results was obtained. Furthermore, we compared our experimental results with those from other experiments related to the transport of hot food. Here, pizza is taken as the example, and it is shown that delivering time can be increased three-fold.

    Para evitar la proliferación de microorganismos, los alimentos cocinados deben ser transportados a temperaturas entre 60 y 70ºC. Los Materiales con Cambio de Fase a base de Aleaciones Moleculares (MAPCM representan una solución en este tipo de aplicaciones. Para ello hemos diseñado y probado un contenedor que permite el transporte a temperatura controlada. Se ha realizado la experimentación y simulación numérica de la transferencia de calor en el dispositivo con el objetivo de determinar su rendimiento. A pesar de las necesarias simplificaciones, hemos obtenido un buen acuerdo entre resultados experimentales y de simulación. En este trabajo hemos tomado el transporte de pizzas como ejemplo, mostrando que el tiempo de protección térmica puede ser incrementado utilizando aleaciones moleculares.

  2. The use of stock with various contents of n-alkanes in G-64 installations

    Energy Technology Data Exchange (ETDEWEB)

    Dorodnova, V.S.; Martirosov, R.A.; Martynenko, A.G.; Okhrimenko, N.V.; Pereverzev, A.N.

    1979-01-01

    The industrial savings indicators of installations for the carbide separation of paraffin decrease with a processing of the fraction of diesel fuel from west Siberian petroleum with a content of 10 to 12% of n-paraffins. Presentation is made of the results of the calculations of the indicators of the operation of the G-64 installation for fractions of diesel fuel, with a boiling temperature of 200 to 320/sup 0/ and containing 30% (for Stavoropolsk), 20% (for Ukhtinsk) and 15% (for Romashkin oils) occurrence of n-paraffins. It is shown that for the processing of the required amount of paraffin at the G-64 installation, it is expedient to use the stock with an occurrence of 18% to 24% of n-paraffins. With this, besides paraffin, a significant amount of denormalizers are obtained which can be drawn into the composition of cold and export diesel fuels. The use in the capacity of the stock of diesel fraction of low and average paraffin bearing oil with a ratio of carbamide to the stock of 0.4 to 0.5 (mass.) insures the production of two commercial products -- liquid paraffins and diesel fuels.

  3. Density and Compressibility of Multicomponent n-Alkane Mixtures up to 463 K and 140 MPa

    DEFF Research Database (Denmark)

    Regueira, Teresa; Glykioti, Maria-Lito; Stenby, Erling Halfdan

    2017-01-01

    Density measurements of two ternary alkane mixtures (methane/n-butane/n-decane and methane/n-butane/n-dodecane) and two multicomponent mixtures composed of methane/n-butane/n-octane/n-dodecane/n-hexadecane/n-eicosane were performed in the temperature range from (278.15 to 463.15) K and pressures ......–Redlich–Kwong (SRK), Peng–Robinson (PR), Perturbed Chain Statistical Associating Fluid Theory (PC-SAFT), and Soave-Benedict-Webb-Rubin (Soave-BWR) were used for predicting the experimental density values as well as the excess volumes....... to 140 MPa. The isothermal compressibility values of these mixtures were obtained by differentiation from a Tait-type fitting of experimental densities as a function of temperature and pressure. Excess volume of the studied mixtures was also determined. Four different equations of state, that is, Soave...

  4. The use of n-alkane markers to estimate the intake and apparent ...

    African Journals Online (AJOL)

    However, the effect of the higher recovery of the dosed marker needs further investigation. The estimates of apparent dry matter digestibility corresponded well with measured values, provided the factor for the incomplete faecal recovery of the internal alkanes was included in the calculation. It was concluded that the alkane ...

  5. XH···C hydrogen bonds in n-alkane-HX

    Indian Academy of Sciences (India)

    Hada M, Ehara K, Toyota K, Fukuda R, Hasegawa J,. Ishida M, Nakajima T, Honda Y, Kitao O, Nakai H,. Klene M, Li X, Knox J E, Hratchian H P, Cross J B,. Adamo C, Jaramillo J, Gomperts R, Stratmann R E,. Yazyev O, Austin A J, Cammi R, Pomelli C, Ochterski. J W, Ayala P Y, Morokuma K, Voth G A, Salvador P,.

  6. Consistency of plant-specific n-alkane patterns in plaggen ecosystems: a review

    NARCIS (Netherlands)

    Kirkels, F.M.S.A.; Jansen, B.; Kalbitz, K.

    2013-01-01

    Plaggen soils, formed by various vegetational inputs during century-long plaggen (i.e. sod) application, comprise remarkably stable organic matter. Source identification could contribute to a better understanding of carbon stabilization mechanisms in soils and reconstruction of Holocene vegetation

  7. The phase behavior of a hard sphere chain model of a binary n-alkane mixture

    International Nuclear Information System (INIS)

    Malanoski, A. P.; Monson, P. A.

    2000-01-01

    Monte Carlo computer simulations have been used to study the solid and fluid phase properties as well as phase equilibrium in a flexible, united atom, hard sphere chain model of n-heptane/n-octane mixtures. We describe a methodology for calculating the chemical potentials for the components in the mixture based on a technique used previously for atomic mixtures. The mixture was found to conform accurately to ideal solution behavior in the fluid phase. However, much greater nonidealities were seen in the solid phase. Phase equilibrium calculations indicate a phase diagram with solid-fluid phase equilibrium and a eutectic point. The components are only miscible in the solid phase for dilute solutions of the shorter chains in the longer chains. (c) 2000 American Institute of Physics

  8. Demens Film

    DEFF Research Database (Denmark)

    Ridder, Hanne Mette Ochsner

    2012-01-01

    I forbindelse med opstarten af Demens Film projektet har der været nedsat en ekspertgruppe, som er kommet med en række anbefalinger omkring film til mennesker med demens. Anbefalingerne skal bruges i de næste faser af projektet. Deltagerne i ekspertgruppen var sammensat af en bred gruppe...... fagpersoner inde for forskellige fagområder. Læs mere om gruppens anbefalinger og sammensætning af ekspertgruppen i den kort rapport som er offentlig tilgængelig. Læs Ekspertgruppe anbefalingerne til Demens Film projekt....

  9. Polymer films

    Science.gov (United States)

    Granick, Steve; Sukhishvili, Svetlana A.

    2004-05-25

    A film contains a first polymer having a plurality of hydrogen bond donating moieties, and a second polymer having a plurality of hydrogen bond accepting moieties. The second polymer is hydrogen bonded to the first polymer.

  10. Science Fiction on Film.

    Science.gov (United States)

    Burmester, David

    1985-01-01

    Reviews science fiction films used in a science fiction class. Discusses feature films, short science fiction films, short story adaptations, original science fiction pieces and factual science films that enrich literature. (EL)

  11. Black Films and Film-Makers.

    Science.gov (United States)

    Patterson, Lindsay, Ed.

    The development of black films and the attitudes of the film industry toward black films and black actors are some of the topics examined in this anthology of essays. Section 1, "Nigger to Supernigger," contains such articles as "The Death of Rastus: Negroes in American Films" by Thomas R. Cripps and "Folk Values in a New Medium" by Alain Locke…

  12. The role of alkenes produced during hydrous pyrolysis of a shale

    Energy Technology Data Exchange (ETDEWEB)

    Leif, R.N.; Simoneit, B.R.T. [Oregon State Univ., Corvallis, OR (United States). College of Oceanic and Atmospheric Sciences

    2000-07-01

    Hydrous pyrolysis experiments conducted on Messel shale with D{sub 2}O demonstrated that a large amount of deuterium becomes incorporated into the hydrocarbons generated from the shale kerogen. In order to understand the pathway of deuterium (and protium) exchange and the role of water during hydrous pyrolysis, we conducted a series of experiments using aliphatic compounds (1,13-tetradecadiene, 1-hexadecene, eicosane and dotriacontane) as probe molecules. These compounds were pyrolyzed in D{sub 2}O, shale/D{sub 2}O, and shale/H{sub 2}O and the products analyzed by GC-MS. In the absence of powdered shale, the incorporation of deuterium from D{sub 2}O occurred only in olefinic compounds via double bond isomerization. The presence of shale accelerated deuterium incorporation into the olefins and resulted in a minor amount of deuterium incorporation in the saturated n-alkanes. The pattern of deuterium substitution of the diene closely matched the deuterium distribution observed in the n-alkanes generated from the shale kerogen in the D{sub 2}O/shale pyrolyses. The presence of the shale also resulted in reduction (hydrogenation) of olefins to saturated n-alkanes with concomitant oxidation of olefins to ketones. These results show that under hydrous pyrolysis conditions, kerogen breakdown generates n-alkanes and terminal n-alkenes by free radical hydrocarbon cracking of the aliphatic kerogen structure. The terminal n-alkenes rapidly isomerize to internal alkenes via acid-catalyzed isomerization under hydrothermal conditions, a significant pathway of deuterium (and protium) exchange between water and the hydrocarbons. These n-alkenes simultaneously undergo reduction to n-alkanes (major) or oxidation to ketones (minor) via alcohols formed by the hydration of the alkenes. (Author)

  13. Film: An Introduction.

    Science.gov (United States)

    Fell, John L.

    "Understanding Film," the opening section of this book, discusses perceptions of and responses to film and the way in which experiences with and knowledge of other media affect film viewing. The second section, "Film Elements," analyzes the basic elements of film: the use of space and time, the impact of editing, sound and color, and the effects…

  14. Film and History.

    Science.gov (United States)

    Schaber, Robin L.

    2002-01-01

    Provides an annotated bibliography of Web sites that focus on using film to teach history. Includes Web sites in five areas: (1) film and education; (2) history of cinema; (3) film and history resources; (4) film and women; and (5) film organizations. (CMK)

  15. Ferroelectric ultrathin perovskite films

    Science.gov (United States)

    Rappe, Andrew M; Kolpak, Alexie Michelle

    2013-12-10

    Disclosed herein are perovskite ferroelectric thin-film. Also disclosed are methods of controlling the properties of ferroelectric thin films. These films can be used in a variety materials and devices, such as catalysts and storage media, respectively.

  16. Film Noir Style Genealogy

    OpenAIRE

    Rietuma, Dita

    2012-01-01

    Annotation for the Doctoral Work Film Noir Style Genealogy (The Genealogy of the Film Noir Style) The doctoral work topic Film Noir Style Genealogy encompasses traditionally approved world film theory views on the concept of film noir and its related cinematographic heritage, and an exploration of its evolution and distinctive style, including – the development of film noir in the USA, Europe, and also in Latvia, within the context of both socio-political progression and the paradigm of m...

  17. Contemporary Films' Mini Course on Film Study.

    Science.gov (United States)

    Schillaci, Peter

    This minicourse on film study can be a unit in English, in arts, or in the humanities. It can help to launch a film study course or complement an introduction to theater. Whatever form it takes, it helps to build a bridge to the student's media environment. Part one, the language of images, utilizes four films which demonstrate the basic elements…

  18. The Evolution of Film: Rethinking Film Studies

    OpenAIRE

    Harbord, Janet P.

    2007-01-01

    How is film changing? What does it do, and what do we do with it? This book examines the reasons why we should be studying film in the twenty-first century, connecting debates from philosophy, anthropology and new media with historical concerns of film studies.

  19. Film quality in film mammography. Pt. 2

    International Nuclear Information System (INIS)

    Friedrich, M.; Weskamp, P.; Freie Univ. Berlin

    1976-01-01

    During consideration of three film mammographic systems, the concept of signal/noise ratio is developed as a quantitative measure of film quality. The ability to recognise detail related to detail size, film blackening and exposure geometry was studied for various systems, and the quality profiles are discussed. There is a considerable difference in quality between industrial films without screens and film-screen combinations; however, exposure geometry during mammography has a considerable effect which tends to reduce the difference. Consequently, detail sizes of 200 μ to 1,000 μ (including the majority of mammographic micro-calcifications) are shown about equally well. Contrast for the lo-dose system is somewhat less than for adequately exposed industrial film. Over-exposure with the lo-dose system, contrary to industrial film, rapidly leads to unsatisfactory results. On the other hand it is often not possible to obtain an adequate exposure when using industrial film. For these reasons it is often an advantage to examine large breasts and the dense breasts of young women with a film-screen combination which requires approximately one eighth of the dose necessary for industrial film. For small or easily compressable breasts best results are obtained, using an adequate exposure by employing industril film; radiation dose it then acceptable. (orig./ORU) [de

  20. Uniformly irradiated polymer film

    International Nuclear Information System (INIS)

    Fowler, S.L.

    1979-01-01

    Irradiated film having substantial uniformity in the radiation dosage profile is produced by irradiating the film within a trough having lateral deflection blocks disposed adjacent the film edges for deflecting electrons toward the surface of the trough bottom for further deflecting the electrons toward the film edge

  1. Films and dark room

    International Nuclear Information System (INIS)

    Abdul Nassir Ibrahim; Azali Muhammad; Ab. Razak Hamzah; Abd. Aziz Mohamed; Mohamad Pauzi Ismail

    2008-01-01

    After we know where the radiographic come from, then we must know about the film and also dark room. So, this chapter 5 discusses the two main components for radiography work that is film and dark room, places to process the film. Film are structured with three structured that are basic structured, emulsion and protection structured. So, this film can be classified either with their speed, screen and standard that used. The process to wash the film must be done in dark room otherwise the radiographer cannot get what are they inspected. The processing of film will be discussed briefly in next chapter.

  2. Film som kunst

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    2013-01-01

    Films by artists induce scholars to work across art, film and cultural history. Accordingly, this article adopts an interdisciplinary approach to the British-Nigerian artist Yinka Shonibare’s film Un Ballo in Maschera (2004). The film is grounded in Shonibare’s unique use of African-print fabric...... in conjunction with references to European cultural and political history, but the film is also – it is alleged – rooted in Black British cinema and the transnational postcolonialism which emerged in the UK of the 1980s. The article starts with a general introduction to Shonibare’s art and the colonial...... connotations of the African-print fabric, which are also central to the critique of power in Un Ballo in Maschera. Its critical agenda is then analysed and put into historical perspective by relating the film to Black British film. A comparison with the Black Audio Film Collective’s key work Handsworth Songs...

  3. The Educational Film Industry

    Science.gov (United States)

    Tortora, Vincent R.; Schillaci, Peter

    1975-01-01

    Increased dialog is needed among educational film producers, distributors, and consumers in order to be sure that what is being produced meets educators' needs and also to help solve the financial problems of the film industry. (LS)

  4. Electrochromic nanocomposite films

    Science.gov (United States)

    Milliron, Delia; Llordes, Anna; Buonsanti, Raffaella; Garcia, Guillermo

    2018-04-10

    The present invention provides an electrochromic nanocomposite film. In an exemplary embodiment, the electrochromic nanocomposite film, includes (1) a solid matrix of oxide based material and (2) transparent conducting oxide (TCO) nanostructures embedded in the matrix. In a further embodiment, the electrochromic nanocomposite film farther includes a substrate upon which the matrix is deposited. The present invention also provides a method of preparing an electrochromic nanocomposite film.

  5. Lars von Triers film

    DEFF Research Database (Denmark)

    Nielsen, Lisbeth Overgaard

    2007-01-01

    Afhandlingen undersøger Lars von Triers filmæstetik, som den kommer til udtryk i spillefilmene fra perioden 1984-2007. Afhandlingen analyserer de enkelte films stil, virkningsstrategi og betydningsdannelse.......Afhandlingen undersøger Lars von Triers filmæstetik, som den kommer til udtryk i spillefilmene fra perioden 1984-2007. Afhandlingen analyserer de enkelte films stil, virkningsstrategi og betydningsdannelse....

  6. Defining Documentary Film

    DEFF Research Database (Denmark)

    Juel, Henrik

    2006-01-01

    A discussion of various attemts at defining documentary film regarding form, content, truth, stile, genre or reception - and a propoposal of a positive list of essential, but non-exclusive characteristica of documentary film......A discussion of various attemts at defining documentary film regarding form, content, truth, stile, genre or reception - and a propoposal of a positive list of essential, but non-exclusive characteristica of documentary film...

  7. Personnel photographic film dosimetry

    International Nuclear Information System (INIS)

    Keirim-Markus, I.B.

    1981-01-01

    Technology of personnel photographic film dosimetry (PPD) based on the photographic effect of ionizing radiation is described briefly. Kinds of roentgen films used in PPD method are enumerated, compositions of a developer and fixing agents for these films are given [ru

  8. Radiochromic film dosimetry

    International Nuclear Information System (INIS)

    Xu Zhiyong

    2002-01-01

    Radiochromic film dosimetry was developed to measure ionization irradiation dose for industry and medicine. At this time, there are no comprehensive guideline on the medical application, calibration method and densitometer system for medicine. The review gives update on Radiochromic film dosimetry used for medicine, including principles, film model and material, characteristics, calibration method, scanning densitometer system and medical application

  9. Australian Film Studies.

    Science.gov (United States)

    Breen, Myles P.

    Although Australia had a vigorous film industry in the silent film era, it was stifled in the 1930s when United States and British interests bought up the Australian distribution channels and closed down the indigenous industry. However, the industry and film study have undergone a renaissance since the advent of the Labor government in 1972,…

  10. Getting into Film.

    Science.gov (United States)

    London, Mel

    This book describes the various aspects of the film industry and the many jobs related to filmmaking, stressing that no "formula" exists for finding a successful career in the film industry. Chapters provide information on production, writing for film, cinematography, editing, music, sound, animation and graphics, acting and modeling, the "unsung…

  11. The Sponsored Film.

    Science.gov (United States)

    Klein, Walter J.

    For public relations professionals and would-be sponsors of films, this book provides guidelines for understanding the film medium and its potential as a persuasive force in industry, government, organizations, and religious orders. For filmmakers, it brings together practical information needed to survive in the sponsored-film industry and to…

  12. Introduction to Film Making.

    Science.gov (United States)

    Davis, Robert E.

    This booklet is intended for teachers who are now teaching units in film production as part of a program in communication or who wish to begin work with filmmaking in such a program. The first section is intended to serve as a brief introduction to film theory, while a major portion of the rest of the booklet is devoted to film projects which may…

  13. Teaching Culture Through Films

    Institute of Scientific and Technical Information of China (English)

    徐婷

    2016-01-01

    Cultural teaching is an issue which is associated with complexity and paradox and also it is a big challenge for faculty. Teaching culture through films has become an important way of cross-cultural teaching This paper focuses on the reasons for teaching culture through films, the value and how it works. And finally it leads out the prospects of cultural teaching through films.

  14. Third O2 addition reactions promote the low-temperature auto-ignition of n-alkanes

    KAUST Repository

    Wang, Zhandong; Sarathy, Mani

    2016-01-01

    kinetic mechanism is considered. The advanced combustion phasing is initiated by the formation and destruction of additional radical chain-branching intermediates produced in the third O2 addition process, e.g. keto-dihydroperoxides and/or keto

  15. Fractionation of hydrogen, oxygen and carbon isotopes in n-alkanes and cellulose of three Sphagnum species

    NARCIS (Netherlands)

    Brader, A.V.; Winden, J.F.; Bohncke, S.J.P.; Beets, C.J.; Reichart, G.-J.; De Leeuw, J.W.

    2010-01-01

    Compound-specific isotope measurements of organic compounds are increasingly important in palaeoclimate reconstruction. Searching for more accurate peat-based palaeoenvironmental proxies, compound-specific fractionation of stable C, H and O isotopes of organic compounds synthesized by Sphagnum were

  16. Insights into the Anaerobic Biodegradation Pathway of n-Alkanes in Oil Reservoirs by Detection of Signature Metabolites

    Science.gov (United States)

    Bian, Xin-Yu; Maurice Mbadinga, Serge; Liu, Yi-Fan; Yang, Shi-Zhong; Liu, Jin-Feng; Ye, Ru-Qiang; Gu, Ji-Dong; Mu, Bo-Zhong

    2015-01-01

    Anaerobic degradation of alkanes in hydrocarbon-rich environments has been documented and different degradation strategies proposed, of which the most encountered one is fumarate addition mechanism, generating alkylsuccinates as specific biomarkers. However, little is known about the mechanisms of anaerobic degradation of alkanes in oil reservoirs, due to low concentrations of signature metabolites and lack of mass spectral characteristics to allow identification. In this work, we used a multidisciplinary approach combining metabolite profiling and selective gene assays to establish the biodegradation mechanism of alkanes in oil reservoirs. A total of twelve production fluids from three different oil reservoirs were collected and treated with alkali; organic acids were extracted, derivatized with ethanol to form ethyl esters and determined using GC-MS analysis. Collectively, signature metabolite alkylsuccinates of parent compounds from C1 to C8 together with their (putative) downstream metabolites were detected from these samples. Additionally, metabolites indicative of the anaerobic degradation of mono- and poly-aromatic hydrocarbons (2-benzylsuccinate, naphthoate, 5,6,7,8-tetrahydro-naphthoate) were also observed. The detection of alkylsuccinates and genes encoding for alkylsuccinate synthase shows that anaerobic degradation of alkanes via fumarate addition occurs in oil reservoirs. This work provides strong evidence on the in situ anaerobic biodegradation mechanisms of hydrocarbons by fumarate addition. PMID:25966798

  17. Influence of Pt nanoparticles modified by La and Ce oxides on catalytic dehydrocyclization of n-alkanes

    Directory of Open Access Journals (Sweden)

    A.H. Samia

    2015-06-01

    Full Text Available Catalytic reforming accounts for a large share of the world’s gasoline production, it is the most important source of aromatics for the petrochemical industry. In addition, reforming of hydrocarbon on the dual-function catalysts has been found to form fundamentally different products in hydrogen diluents. Typical catalysts employed for this reforming process are Pt/Al2O3 and Pt-M/Al2O3, M being the promoter. These solids are characterized by both acid and metal functions which catalyze dehydrocyclization, dehydrogenation, isomerization and cracking processes. In this regard, information about cerium and lanthanum, as promoters, is hardly revealed. The present work aims to study the performance of Pt/Al2O3 catalysts modified by lanthanum or cerium during the conversion of cyclohexane, n-hexane and n-heptane. Catalytic activities of the prepared catalysts were tested using a micro catalytic pulse technique. Physicochemical characterization of the solid catalysts such as, surface area (SBET, Fourier transform infrared (FTIR, differential scanning calorimetry (DSC, thermogravimetric analysis (TGA, hydrogen-temperature programed reduction (H2-TPR, hydrogen-temperature-programed desorption (H2-TPD, CO2-TPD, NH3-TPD, high resolution transmission electron microscopy (HRTEM and X-ray diffraction (XRD were depicted. Results indicated clearly that Pt/Al2O3 catalyst is selective toward dehydrogenation to benzene which could be explained as due to the decrease in the active acid sites and the comparative segregation of the alumina support especially at 3% load of CeO. The presence of La2O3 in the Pt/Al2O3 catalyst promotes aromatization of n-hexane and n-heptane, also the dehydrocyclization of n-hexane is more difficult than that of n-heptane. Thus, modification of the Pt/Al2O3 catalyst by La, resulted in a more active and selective reforming catalyst.

  18. Environmental controls on δ13C variations of Sphagnum derived n-alkanes in the Dajiuhu peatland, central China

    Science.gov (United States)

    Huang, X.; Xue, J.; Wang, X.; WANG, H.; Meyers, P. A.; Qin, Y.; Gong, L.; Ding, W.

    2012-12-01

    Northern peatlands are one of the very important atmospheric carbon sinks and represent about 30% of the global soil organic carbon (Gorham, 1991). In peatland conditions, high water levels and consequent anoxia make them an important source of methane. A recent study revealed that methanotrophic bacteria growing on stems or in hyaline cells of Sphagnum can provide methane derived carbon for photosynthesis (Raghoebarsing et al., 2005). This interaction has been found to be globally prevalent in peat-moss ecosystems and can contribute up to 30% of carbon for Sphagnum photosynthesis (Kip et al., 2010). Due to the uptake of 13C-depleted methane-derived CO2 and the sensitivity of methane oxidizing bacteria to the surface wetness, the carbon isotopic signatures of Sphagnum derived lipids have the potential to be used as a proxy for the surface wetness in peatlands and hence as paleoclimate archives (Nichols et al., 2009). In this study, we report the δ13C variations of the Sphagnum derived n-C23 alkane in both fresh Sphagnum and surface peat samples in the Dajiuhu peatland, a small fen located in the Shennongjia forestry region, Hubei province, central China. The δ13C23 values of Sphagnum show a negative correlation with the water level, supporting the idea that that the carbon isotope fractionation of Sphagnum is mainly manifested by the diffusion resistance of CO2 in hyaline cells of Sphagnum. However, δ13C23 values of surface peats collected in Sphagnum dominated ecosystems display a positive relation with the water level when the water level is less than 30 cm. Such an inconsistency probably results from the higher potential for methane-oxidizing activity in the lower parts of Sphagnum in fen meadows. When the water level is higher than 30 cm, the influence of symbiotic methanotrophic bacteria on Sphagnum derived n-C23 alkane is weak or nearly absent. These findings provide direct evidence to support the hypothesis that the carbon isotopic signatures of Sphagnum derived lipids can be used as a proxy of surface wetness in peatlands. References Gorham, E., 1991. Northern peatlands: role in the carbon cycle and probable responses to climatic warming. Ecological Applications, 1, 182-195. Kip, N., van Winden, J.F., Pan, Y., et al., 2010. Global prevalence of methane oxidation by symbiotic bacteria in peat-moss ecosystems. Nature Geosciences 3, 617-621. Nichols, JE, Walcott, M, Bradley, R., et al., 2009. Quantitative assessment of precipitation seasonality and summer surface wetness using ombrotrophic sediments from an Arctic Norwegian peatland. Quaternary Research, 2009, 72: 443-451. Raghoebarsing, A.A., Smolders, A.J.P., Schmid, M.C., et al., 2005. Methanotrophic symbionts provide carbon for photosynthesis in peat bogs. Nature 436, 1153-1156.

  19. Effect of leaf litter degradation and seasonality on D/H isotope ratios of n-alkane biomarkers

    NARCIS (Netherlands)

    Zech, M.; Pedentchouk, N.; Buggle, B.; Leiber, K.; Kalbitz, K.; Markovic, S.B.; Glaser, B.

    2011-01-01

    During the last decade, compound-specific hydrogen isotope analysis of plant leaf-wax and sedimentary n-alkyl lipids has become a promising tool for paleohydrological reconstructions. However, with the exception of several previous studies, there is a lack of knowledge regarding possible effects of

  20. Predictions of homogeneous nucleation rates for n-alkanes accounting for the diffuse phase interface and capillary waves

    Czech Academy of Sciences Publication Activity Database

    Planková, Barbora; Vinš, Václav; Hrubý, Jan

    2017-01-01

    Roč. 147, č. 16 (2017), č. článku 164702. ISSN 0021-9606 R&D Projects: GA MŠk(CZ) 7F14466; GA ČR(CZ) GJ15-07129Y Institutional support: RVO:61388998 Keywords : nucleation * classical nucleation theory * density gradient theory Subject RIV: BJ - Thermodynamics OBOR OECD: Thermodynamics Impact factor: 2.965, year: 2016

  1. Film studies the basics

    CERN Document Server

    Villarejo, Amy

    2013-01-01

    Film Studies: The Basics is a compelling guide to the study of cinema in all its forms. This second edition has been thoroughly revised and updated to take account of recent scholarship, the latest developments in the industry and the explosive impact of new technologies. Core topics covered include:   The history, technology and art of cinema Theories of stardom, genre and film-making The movie industry from Hollywood to Bollywood Who does what on a film set   Complete with film stills, end-of-chapter summaries and a substantial glossary, Film Studies: The Basics is the ideal introduction to those new to the study of cinema.

  2. Thin film processes II

    CERN Document Server

    Kern, Werner

    1991-01-01

    This sequel to the 1978 classic, Thin Film Processes, gives a clear, practical exposition of important thin film deposition and etching processes that have not yet been adequately reviewed. It discusses selected processes in tutorial overviews with implementation guide lines and an introduction to the literature. Though edited to stand alone, when taken together, Thin Film Processes II and its predecessor present a thorough grounding in modern thin film techniques.Key Features* Provides an all-new sequel to the 1978 classic, Thin Film Processes* Introduces new topics, and sever

  3. Pyrolyzed thin film carbon

    Science.gov (United States)

    Tai, Yu-Chong (Inventor); Liger, Matthieu (Inventor); Harder, Theodore (Inventor); Konishi, Satoshi (Inventor); Miserendino, Scott (Inventor)

    2010-01-01

    A method of making carbon thin films comprises depositing a catalyst on a substrate, depositing a hydrocarbon in contact with the catalyst and pyrolyzing the hydrocarbon. A method of controlling a carbon thin film density comprises etching a cavity into a substrate, depositing a hydrocarbon into the cavity, and pyrolyzing the hydrocarbon while in the cavity to form a carbon thin film. Controlling a carbon thin film density is achieved by changing the volume of the cavity. Methods of making carbon containing patterned structures are also provided. Carbon thin films and carbon containing patterned structures can be used in NEMS, MEMS, liquid chromatography, and sensor devices.

  4. Screen-film mammography

    International Nuclear Information System (INIS)

    Logan, W.W.; Janus, J.A.

    1987-01-01

    The development of screen-film mammography has resulted in the re-emergence of confidence, rather than fear, in mammography. When screen-film mammography is performed with state-of-the-art dedicated equipment utilizing vigorous breast compression and a ''soft'' x-ray beam for improved contrast, screen-film images are equivalent or superior to those of reduced-dose xeromammography and superior to those of nonscreen film mammography. Technological aids for conversion from xeromammographic or nonscreen film mammographic techniques to screen-film techniques have been described. Screen-film mammography should not be attempted until dedicated equipment has been obtained and the importance of vigorous compression has been understood

  5. Ceramic Composite Thin Films

    Science.gov (United States)

    Ruoff, Rodney S. (Inventor); Stankovich, Sasha (Inventor); Dikin, Dmitriy A. (Inventor); Nguyen, SonBinh T. (Inventor)

    2013-01-01

    A ceramic composite thin film or layer includes individual graphene oxide and/or electrically conductive graphene sheets dispersed in a ceramic (e.g. silica) matrix. The thin film or layer can be electrically conductive film or layer depending the amount of graphene sheets present. The composite films or layers are transparent, chemically inert and compatible with both glass and hydrophilic SiOx/silicon substrates. The composite film or layer can be produced by making a suspension of graphene oxide sheet fragments, introducing a silica-precursor or silica to the suspension to form a sol, depositing the sol on a substrate as thin film or layer, at least partially reducing the graphene oxide sheets to conductive graphene sheets, and thermally consolidating the thin film or layer to form a silica matrix in which the graphene oxide and/or graphene sheets are dispersed.

  6. Film: Genres and Genre Theory

    DEFF Research Database (Denmark)

    Bondebjerg, Ib

    2015-01-01

    Genre is a concept used in film studies and film theory to describe similarities between groups of films based on aesthetic or broader social, institutional, cultural, and psychological aspects. Film genre shares similarities in form and style, theme, and communicative function. A film genre...

  7. Film Music. Factfile No. 8.

    Science.gov (United States)

    Elsas, Diana, Ed.; And Others

    Organizations listed here with descriptive information include film music clubs and music guilds and associations. These are followed by a representative list of schools offering film music and/or film sound courses. Sources are listed for soundtrack recordings, sound effects/production music, films on film music, and oral history programs. The…

  8. Demagnetization in photomagnetic films

    Energy Technology Data Exchange (ETDEWEB)

    Pajerowski, Daniel M., E-mail: daniel@pajerowski.com [NIST Center for Neutron Research, Gaithersburg, Maryland 20899 (United States); Hallock, Scott J. [NIST Center for Neutron Research, Gaithersburg, Maryland 20899 (United States); Winston Churchill High School, Potomac, Maryland 20854 (United States)

    2012-05-15

    We present a model for demagnetization in photomagnetic films, and investigate different regimes for the magnetizing process using finite element analysis. It is found that the demagnetizing factor may depend strongly upon the high-spin fraction of the film, and the specifics of the dependence are dictated by the microscopic morphology of the photomagnetic domains. This picture allows for facile interpretation of existing data on photomagnetic films, and can even explain an observed photoinduced decrease in low-field magnetization concurrent with increase in high-spin fraction. As a whole, these results reiterate the need to consider demagnetizing effects in photomagnetic films. - Highlights: Black-Right-Pointing-Pointer Finite element methods are used to examine demagnetization in photomagnetic films. Black-Right-Pointing-Pointer Under the right conditions, photomagnetic films may show a photoinduced decrease. Black-Right-Pointing-Pointer Demagnetization in photomagnets will be important to consider in possible devices.

  9. Superconducting thin films

    International Nuclear Information System (INIS)

    Hebard, A.F.; Vandenberg, J.M.

    1982-01-01

    This invention relates to granular metal and metal oxide superconducting films formed by ion beam sputter deposition. Illustratively, the films comprise irregularly shaped, randomly oriented, small lead grains interspersed in an insulating lead oxide matrix. The films are hillock-resistant when subjected to thermal cycling and exhibit unusual josephson-type switching characteristics. Depending on the oxygen content, a film may behave in a manner similar to that of a plurality of series connected josephson junctions, or the film may have a voltage difference in a direction parallel to a major surface of the film that is capable of being switched from zero voltage difference to a finite voltage difference in response to a current larger than the critical current

  10. Underwater 3D filming

    Directory of Open Access Journals (Sweden)

    Roberto Rinaldi

    2014-12-01

    Full Text Available After an experimental phase of many years, 3D filming is now effective and successful. Improvements are still possible, but the film industry achieved memorable success on 3D movie’s box offices due to the overall quality of its products. Special environments such as space (“Gravity” and the underwater realm look perfect to be reproduced in 3D. “Filming in space” was possible in “Gravity” using special effects and computer graphic. The underwater realm is still difficult to be handled. Underwater filming in 3D was not that easy and effective as filming in 2D, since not long ago. After almost 3 years of research, a French, Austrian and Italian team realized a perfect tool to film underwater, in 3D, without any constrains. This allows filmmakers to bring the audience deep inside an environment where they most probably will never have the chance to be.

  11. Den danske independent film

    DEFF Research Database (Denmark)

    Hansen, Kim Toft

    2014-01-01

    at producere film, og derved er filmproduktion potentielt gjort tilgængelig for en større gruppe personer som både afsender og modtager. For det fjerde implicerer diskussionen af de to film også genre- og stilmæssige spørgsmål om dansk filmkultur, fordi indiefilmen både i film og uden for filmene italesætter...

  12. Religion og film

    DEFF Research Database (Denmark)

    Hvithamar, Annika; Eskjær, Mikkel Fugl

    2007-01-01

    Artiklen søger at stipulere en ramme for analyse af religion og film. Dels ved at række ud over den blotte konstatering af tilstedeværelse af religiøse elementer i film, dels ved at anslå en række temaer, der kan anvendes til analyse af sådanne film (individualisering, (de-)sekularisering, banal...

  13. Horror films and psychiatry.

    Science.gov (United States)

    Friedman, Susan Hatters; Forcen, Fernando Espi; Shand, John Preston

    2014-10-01

    Horror films have been popular for generations. The purpose of this article is to illustrate psychiatric conditions, themes and practice seen in horror films. Horror films often either include psychiatrists as characters or depict (Hollywood's dangerous version of) serious mental illness. Demonic possession, zombies, and 'slasher' killers are described, as well as the horror genre's characterizations of psychiatrists. © The Royal Australian and New Zealand College of Psychiatrists 2014.

  14. Renaissance of the Film.

    Science.gov (United States)

    Bellone, Julius, Ed.

    The post-World War II period was one of the liveliest in the history of the cinema. This is a collection of 33 critical articles on some of the best films of the perd. Most of the essays explicate the themes and symbols of the films. The essays deal with these films: "The Apu Trilogy,""L'Avventura,""Balthazar,""Blow-Up,""Bonnie and Clyde," Citizen…

  15. Film in concert

    OpenAIRE

    2017-01-01

    From the very beginning of cinema, music always played an important role in the history of filmmaking. Nonetheless, film music is judged by critics as a kind of low-grade art form. However, the majority of film score composers enjoyed a classical education and composed as well for the silver screen as for the concert hall. Film music also has its roots in the musical era of romanticism. Therefore, symphonic film scores can be regarded as program music in a broader sense. These scores were inf...

  16. Film, Neuroaesthetics, and Empathy

    DEFF Research Database (Denmark)

    Grodal, Torben Kragh; Kramer, Mette

    2014-01-01

    The article analyzes the link between film viewing and human 'ultra-sociality' (Boyd and Richardson 1998), describing how empathy is supported by mirror resonances but also modified by appraisal mechanisms and how emotions are communicated, It further discusses how 'attainment' to film builds...... on mother-child communication and also how film genres of attachment use such attainment, especially by means of close-ups of human faces and shot-reverse shots. Finally it deals with how films boost development of cognitive and emotional intelligence...

  17. The Possibility of Film Criticism.

    Science.gov (United States)

    Poague, Leland; Cadbury, William

    1989-01-01

    Examines the role of critical language in film criticism. Compares and contrasts Monroe Beardsley's philosophy on film aesthetics with the New Criticism. Outlines some of the contributions Beardsley has made to the study of film criticism. (KM)

  18. Thin Film & Deposition Systems (Windows)

    Data.gov (United States)

    Federal Laboratory Consortium — Coating Lab: Contains chambers for growing thin film window coatings. Plasma Applications Coating Lab: Contains chambers for growing thin film window coatings. Solar...

  19. FAA Film Catalog.

    Science.gov (United States)

    Federal Aviation Administration (DOT), Washington, DC.

    Some 75 films from the U.S. Department of Transportation's Federal Aviation Administration are listed in this catalog. Topics dealt with include aerodynamics, airports, aviation history and careers, flying clubs, navigation and weather. Most of the films are 16mm sound and color productions. Filmstrips requiring a 35mm projector and phonograph or…

  20. What Is Film Phenomenology?

    NARCIS (Netherlands)

    Hanich, Julian; Ferencz-Flatz, Christian

    2016-01-01

    In this article Christian Ferencz-Flatz and I try to give an answer to the question what film phenomenology actually is. We proceed in three steps. First, we provide a survey of five different research practices within current film phenomenological writing: We call them excavation, explanation,

  1. Stabilized chromium oxide film

    Science.gov (United States)

    Garwin, Edward L.; Nyaiesh, Ali R.

    1988-01-01

    Stabilized air-oxidized chromium films deposited on high-power klystron ceramic windows and sleeves having a thickness between 20 and 150.ANG. are useful in lowering secondary electron emission yield and in avoiding multipactoring and window failure due to overheating. The ceramic substrate for the film is chosen from alumina, sapphire or beryllium oxide.

  2. On Teaching Ethnographic Film

    Science.gov (United States)

    Clarfield, Geoffrey

    2013-01-01

    The author of this article, a developmental anthropologist, illustrates how the instructor can use ethnographic films to enhance the study of anthropology and override notions about the scope and efficacy of Western intervention in the Third World, provided the instructor places such films in their proper historical and cultural context. He…

  3. Determining Film Art.

    Science.gov (United States)

    Bullis, Roger

    1974-01-01

    The criteria by which films can and should be analyzed as art are discussed in this paper. A triangular model of theme-form-content is presented with form given greater significance than is usually the case in film criticism. The form-content-theme synthesis is the process in which theme is made clear by means of form and content within an…

  4. Thick film hydrogen sensor

    Science.gov (United States)

    Hoffheins, Barbara S.; Lauf, Robert J.

    1995-01-01

    A thick film hydrogen sensor element includes an essentially inert, electrically-insulating substrate having deposited thereon a thick film metallization forming at least two resistors. The metallization is a sintered composition of Pd and a sinterable binder such as glass frit. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors.

  5. "Fate: The short film"

    OpenAIRE

    Maya Quintana, Jennifer

    2014-01-01

    "Fate: The Short Film" is a four minute short film which reflects the idea that nobody can escape from the fate. It has a good picture and sound quality with an understandable message for all public and with the collaboration of actors, filmmaker, stylist, script advisor and media technician.

  6. Malaysian Cinema, Asian Film

    NARCIS (Netherlands)

    Heide, van der William

    2002-01-01

    This title series departs from traditional studies of national cinema by accentuating the intercultural and intertextual links between Malaysian films and Asian (as well as European and American) film practices. Using cross-cultural analysis, the author characterizes Malaysia as a pluralist society

  7. Abstract Film and Beyond.

    Science.gov (United States)

    Le Grice, Malcolm

    A theoretical and historical account of the main preoccupations of makers of abstract films is presented in this book. The book's scope includes discussion of nonrepresentational forms as well as examination of experiments in the manipulation of time in films. The ten chapters discuss the following topics: art and cinematography, the first…

  8. Protolytic carbon film technology

    Energy Technology Data Exchange (ETDEWEB)

    Renschler, C.L.; White, C.A.

    1996-04-01

    This paper presents a technique for the deposition of polyacrylonitrile (PAN) on virtually any surface allowing carbon film formation with only the caveat that the substrate must withstand carbonization temperatures of at least 600 degrees centigrade. The influence of processing conditions upon the structure and properties of the carbonized film is discussed. Electrical conductivity, microstructure, and morphology control are also described.

  9. Selective inorganic thin films

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, M.L.F.; Weisenbach, L.A.; Anderson, M.T. [Sandia National Laboratories, Albuquerque, NM (United States)] [and others

    1995-05-01

    This project is developing inorganic thin films as membranes for gas separation applications, and as discriminating coatings for liquid-phase chemical sensors. Our goal is to synthesize these coatings with tailored porosity and surface chemistry on porous substrates and on acoustic and optical sensors. Molecular sieve films offer the possibility of performing separations involving hydrogen, air, and natural gas constituents at elevated temperatures with very high separation factors. We are focusing on improving permeability and molecular sieve properties of crystalline zeolitic membranes made by hydrothermally reacting layered multicomponent sol-gel films deposited on mesoporous substrates. We also used acoustic plate mode (APM) oscillator and surface plasmon resonance (SPR) sensor elements as substrates for sol-gel films, and have both used these modified sensors to determine physical properties of the films and have determined the sensitivity and selectivity of these sensors to aqueous chemical species.

  10. Conceiving Landscape through Film

    DEFF Research Database (Denmark)

    Farsø, Mads; Munck Petersen, Rikke

    2015-01-01

    This article shows how the media of film can be integrated, explored and can add value to architectural design studios and practice. It elucidates how film may offer an alternative position in architecture, where landscapes and cities are thought, planned and developed in closer relation...... to their spatial and sensory effects on humans. It underscores that the film camera can work as a kind of amplifier of how we, with our bodies, perceive space and project space. In the “Landscape Film” Studio at University of Copenhagen the film medium was tested as a combined registration and design tool...... for a new Nature Park south of Copenhagen. The final studio films and designs show how resonate recordings of sound, time and a bodily presence may simulate an Einfühling that inspires an alternative architecture of relations: the ambient, the changeable and the volatile. They also emphasize that an ability...

  11. Film sheet cassette

    International Nuclear Information System (INIS)

    1981-01-01

    A novel film sheet cassette is described for handling CAT photographic films under daylight conditions and facilitating their imaging. A detailed description of the design and operation of the cassette is given together with appropriate illustrations. The resulting cassette is a low-cost unit which is easily constructed and yet provides a sure light-tight seal for the interior contents of the cassette. The individual resilient fingers on the light-trap permit the ready removal of the slide plate for taking pictures. The stippled, non-electrostatic surface of the pressure plate ensures an air layer and free slidability of the film for removal and withdrawal of the film sheet. The advantage of the daylight system is that a darkroom need not be used for inserting and removing the film in and out of the cassette resulting in a considerable time saving. (U.K.)

  12. IAEA film library

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1959-01-15

    Most of the scientific and technical films shown during the Second Geneva Conference for the Peaceful Uses of Atomic Energy were donated to IAEA by the producing countries at the end of the Conference. They will form the basic stock for the Agency's loan service intended to provide atomic energy institutions in Member States with film material. A detailed catalogue of the films, classified according to subject and giving conditions of loan or purchase, is now being prepared. In addition to this, information on all films produced in Member Countries dealing with the peaceful uses cf atomic energy is being assembled. The documentary information contained in the films in IAEA's possession relates to the following subjects: national programmes; nuclear physics; accelerators; plasma and fusion; reactors (power, research, material testing and experimental); prospecting and mining; ore dressing; metallurgy; production of fuel elements; treatment of irradiated fuel elements; protection against radiation; detection and counting; uses of radiation in medicine, biochemistry, agriculture and industry; industrial application of nuclear explosions. Most of the commentaries are in the language of the producing country. A few films are available in a choice of two languages. The films donated to the Agency total 82, two of which have been produced in Canada, 13 in France, one in India, one in Romania, one in Spain, 14 in the United Kingdom, one in the Union of South Africa, 47 in the United States of America and two in the USSR: they are mostly illustrations of papers presented at the Second Geneva Conference. In arranging for the circulation of scientific and technical films IAEA wishes to help meet some of the training and information needs of Member States. It is hoped that all organizations producing films on the peaceful uses of atomic energy will entrust copies to the IAEA with a view to their widest possible circulation. In the meantime, the Agency's films have been given

  13. IAEA film library

    International Nuclear Information System (INIS)

    1959-01-01

    Most of the scientific and technical films shown during the Second Geneva Conference for the Peaceful Uses of Atomic Energy were donated to IAEA by the producing countries at the end of the Conference. They will form the basic stock for the Agency's loan service intended to provide atomic energy institutions in Member States with film material. A detailed catalogue of the films, classified according to subject and giving conditions of loan or purchase, is now being prepared. In addition to this, information on all films produced in Member Countries dealing with the peaceful uses cf atomic energy is being assembled. The documentary information contained in the films in IAEA's possession relates to the following subjects: national programmes; nuclear physics; accelerators; plasma and fusion; reactors (power, research, material testing and experimental); prospecting and mining; ore dressing; metallurgy; production of fuel elements; treatment of irradiated fuel elements; protection against radiation; detection and counting; uses of radiation in medicine, biochemistry, agriculture and industry; industrial application of nuclear explosions. Most of the commentaries are in the language of the producing country. A few films are available in a choice of two languages. The films donated to the Agency total 82, two of which have been produced in Canada, 13 in France, one in India, one in Romania, one in Spain, 14 in the United Kingdom, one in the Union of South Africa, 47 in the United States of America and two in the USSR: they are mostly illustrations of papers presented at the Second Geneva Conference. In arranging for the circulation of scientific and technical films IAEA wishes to help meet some of the training and information needs of Member States. It is hoped that all organizations producing films on the peaceful uses of atomic energy will entrust copies to the IAEA with a view to their widest possible circulation. In the meantime, the Agency's films have been given

  14. Films Deliver: Teaching Creatively with Film.

    Science.gov (United States)

    Schillaci, Anthony, Ed.; Culkin, John M., Ed.

    The fifteen papers in this resource guide are grouped into four sections. Section one contains formulations of the basic rationale for screen education and descriptions of new concepts and approaches to film study. Section two presents a definition of the elements involved in filmmaking and viewing, and it describes several model programs which…

  15. Process and apparatus for irradiating film, and irradiated film

    International Nuclear Information System (INIS)

    1981-01-01

    A process for irradiating film is described, which consists of passing the film through an electron irradiation zone having an electron reflection surface disposed behind and generally parallel to the film; and disposing within the irradiation zone adjacent the edges of the film a lateral reflection member for reflecting the electrons toward the reflection surface to further reflect the reflected electrons towards the adjacent edges of the film. (author)

  16. Biomimetic thin film synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Graff, G.L.; Campbell, A.A.; Gordon, N.R.

    1995-05-01

    The purpose of this program is to develop a new process for forming thin film coatings and to demonstrate that the biomimetic thin film technology developed at PNL is useful for industrial applications. In the biomimetic process, mineral deposition from aqueous solution is controlled by organic functional groups attached to the underlying substrate surface. The coatings process is simple, benign, inexpensive, energy efficient, and particularly suited for temperature sensitive substrate materials (such as polymers). In addition, biomimetic thin films can be deposited uniformly on complex shaped and porous substrates providing a unique capability over more traditional line-of-sight methods.

  17. Intermetallic semiconducting films

    CERN Document Server

    Wieder, H H

    1970-01-01

    Intermetallic Semiconducting Films introduces the physics and technology of AшВv compound films. This material is a type of a polycrystalline semiconductor that is used for galvanomagnetic device applications. Such material has a high electron mobility that is ideal for generators and magnetoresistors. The book discusses the available references on the preparation and identification of the material. An assessment of its device applications and other possible use is also enumerated. The book describes the structures and physical parts of different films. A section of the book covers the three t

  18. X-ray film

    International Nuclear Information System (INIS)

    Arndt, U.W.; Gilmore, D.J.; Wonacott, A.J.

    1977-01-01

    The performance of film as an X-ray detector is discussed and its behaviour is compared with that of a perfect Poissonian detector. The efficiency of microdensitometry as a method of extracting the information recorded on the film is discussed. More emphasis is placed in the precision of microdensitometric measurements than on the more obvious characteristic of film speed. The effects of chemical fog and background on the precision of the measurements is considered and it is concluded that the final limit to precision is set by the chemical fog. (B.D.)

  19. Ultrahard carbon nanocomposite films

    Energy Technology Data Exchange (ETDEWEB)

    Siegal, M. P. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1421 (United States); Tallant, D. R. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1421 (United States); Provencio, P. N. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1421 (United States); Overmyer, D. L. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1421 (United States); Simpson, R. L. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1421 (United States); Martinez-Miranda, L. J. [Department of Materials and Nuclear Engineering, University of Maryland, College Park, Maryland 20742 (United States)

    2000-05-22

    Modest thermal annealing to 600 degree sign C of diamondlike amorphous-carbon (a-C) films grown at room temperature results in the formation of carbon nanocomposites with hardness similar to diamond. These nanocomposite films consist of nanometer-sized regions of high density a-C embedded in an a-C matrix with a reduced density of 5%-10%. We report on the evolution of density and bonding topologies as a function of annealing temperature. Despite a decrease in density, film hardness actually increases {approx}15% due to the development of the nanocomposite structure. (c) 2000 American Institute of Physics.

  20. Ultrahard carbon nanocomposite films

    Energy Technology Data Exchange (ETDEWEB)

    SIEGAL,MICHAEL P.; TALLANT,DAVID R.; PROVENCIO,PAULA P.; OVERMYER,DONALD L.; SIMPSON,REGINA L.; MARTINEZ-MIRANDA,L.J.

    2000-01-27

    Modest thermal annealing to 600 C of diamondlike amorphous-carbon (a-C) films grown at room temperature results in the formation of carbon nanocomposites with hardness similar to diamond. These nanocomposite films consist of nanometer-sized regions of high density a-C embedded in an a-C matrix with a reduced density of 5--10%. The authors report on the evolution of density and bonding topologies as a function of annealing temperature. Despite a decrease in density, film hardness actually increases {approximately} 15% due to the development of the nanocomposite structure.

  1. FEMINIST FILM THEORY

    OpenAIRE

    Wijaya, Haris

    2015-01-01

    The developing of film industry has brought us into a complexity of art and business. If the first movie audiences were delighted to see that it was possible to record a moving scene on film; today we debate the desirability behind every movie, rather than just the possibility of capturing an image. Film has already become entertainment tool and communication media with quite powerful effect to influence people at the early 20th century. The problem that happens now is there are not many wome...

  2. Nopal cactus film

    Science.gov (United States)

    Toxqui-López, S.; Olivares-Pérez, A.; Fuentes-Tapia, I.; Conde-Cuatzo, María. G.

    2017-03-01

    Nopal mucilage potentially has certain properties required for the preparation biofilms which can be used as holographic replication recording medium. In this study, mucilage from nopal was extracted and characterized by its ability to form films under different concentration with polyvinyl alcohol. The transmission holographic diffraction gratings (master) were replicated into nopal films. The results showed good diffraction efficiencies. Mucilage from nopal could represent a good option for the development of films to replication holographic, owing to; its low cost and its compatibility with the environmental.

  3. Underwater 3D filming

    OpenAIRE

    Rinaldi, Roberto

    2014-01-01

    After an experimental phase of many years, 3D filming is now effective and successful. Improvements are still possible, but the film industry achieved memorable success on 3D movie’s box offices due to the overall quality of its products. Special environments such as space (“Gravity” ) and the underwater realm look perfect to be reproduced in 3D. “Filming in space” was possible in “Gravity” using special effects and computer graphic. The underwater realm is still difficult to be handled. Unde...

  4. Radiographic film digitizing devices

    International Nuclear Information System (INIS)

    McFee, W.H.

    1988-01-01

    Until recently, all film digitizing devices for use with teleradiology or picture archiving and communication systems used a video camera to capture an image of the radiograph for subsequent digitization. The development of film digitizers that use a laser beam to scan the film represents a significant advancement in digital technology, resulting in improved image quality compared with video scanners. This paper discusses differences in resolution, efficiency, reliability, and the cost between these two types of devices. The results of a modified receiver operating characteristic comparison study of a video scanner and a laser scanner manufactured by the same company are also discussed

  5. Film Scriptwriting: A Practical Manual.

    Science.gov (United States)

    Swain, Dwight V.

    Dealing with both documentary and feature films, this book is a guide to using particular tools and procedures in developing ideas and concepts for writing film scripts. Part one deals with the factual, or documentary, film and discusses the proposal outline, film treatment, sequence outline, shooting script, and narration writing. Part two…

  6. Discovery in Film, Book Two.

    Science.gov (United States)

    Gordon, Malcolm W.

    Approximately 80 16 millimeter (16mm) short films are reviewed in this introduction and guide which attempts to be comprehensive in touching the major areas and styles of 16mm films now being produced. An attempt is made to describe as carefully as possible the style and content of each film and suggest ways in which the films might be used. Films…

  7. Thin films for precision optics

    International Nuclear Information System (INIS)

    Araujo, J.F.; Maurici, N.; Castro, J.C. de

    1983-01-01

    The technology of producing dielectric and/or metallic thin films for high precision optical components is discussed. Computer programs were developed in order to calculate and register, graphically, reflectance and transmittance spectra of multi-layer films. The technology of vacuum evaporation of several materials was implemented in our thin-films laboratory; various films for optics were then developed. The possibility of first calculate film characteristics and then produce the film is of great advantage since it reduces the time required to produce a new type of film and also reduces the cost of the project. (C.L.B.) [pt

  8. Film and Visual Perception

    Science.gov (United States)

    Giltrow, David

    1978-01-01

    One practical method which development film makers can adopt to increase comprehension of important scenes is to eliminate extraneous background information by putting it out of focus, or by shooting against plain backgrounds. (Author/STS)

  9. Film documentaire, lecture documentarisante

    Directory of Open Access Journals (Sweden)

    Roger Odin

    2012-06-01

    Full Text Available Réfléchir sur la relation entre le cinéma et la réalité n’est pas, bien sûr, tenter de distinguer l’espace du documentaire de celui de la fiction, au point que l’opposition avec le film de fiction est devenu le critère de définition privilégié du film documentaire. Prenant acte l’existence, dans le espace de la lecture des films, d’une lecture documentaire ou, plus exactement, d’une lecture documentarisante, nous pensons qu’il y a un ensemble de films que s’affiche comme documentaire (tout le problème est précisément étudier comment s’effetue cet affichage.

  10. Fra bog til film

    DEFF Research Database (Denmark)

    Schepelern, Peter

    2010-01-01

    Efter en historisk oversigt over samspillet mellem film og litteratur i dansk film, opstilles en råkke begreber, som filmatiseringer kan analyseres ud fra. Der ses pa det litteråre vårks status — evt. som klassiker eller bestseller. Der ses pa de centrale filmatiseringsproblemer, forhold som pråger...... adaptionsprocessen fra bog til film. De kan opdeles dels i forhold, der udspringer af filmsprogets specifikke sys- tem, dels forhold, der udspringer af filmens status som massemedium. Den färste kategori er pråget af, at filmsproget generelt fremstiller handling snarere end refleksion, noget konkret snarere end...... noget abstrakt, en scene snarere end et resume og det ydre snarere det indre. Den anden kategori kan forklare filmens tilbäjelighed til åndring af forlågget, til forkortelse, forenkling og modernisering. Eksemplerne er en råkke centrale danske film/romaner...

  11. Thin Film Microbatteries

    International Nuclear Information System (INIS)

    Dudney, Nancy J.

    2008-01-01

    Thin film batteries are built layer by layer by vapor deposition. The resulting battery is formed of parallel plates, much as an ordinary battery construction, just much thinner. The figure (Fig. 1) shows an example of a thin film battery layout where films are deposited symmetrically onto both sides of a supporting substrate. The full stack of films is only 10 to 15 (micro)m thick, but including the support at least doubles the overall battery thickness. When the support is thin, the entire battery can be flexible. At least six companies have commercialized or are very close to commercializing such all-solid-state thin film batteries and market research predicts a growing market and a variety of applications including sensors, RFID tags, and smarter cards. In principle with a large deposition system, a thin film battery might cover a square meter, but in practice, most development is targeting individual cells with active areas less than 25 cm 2 . For very small battery areas, 2 , microfabrication processes have been developed. Typically the assembled batteries have capacities from 0.1 to 5 mAh. The operation of a thin film battery is depicted in the schematic diagram (Fig. 2). Very simply, when the battery is allowed to discharge, a Li + ion migrates from the anode to the cathode film by diffusing through the solid electrolyte. When the anode and cathode reactions are reversible, as for an intercalation compound or alloy, the battery can be recharged by reversing the current. The difference in the electrochemical potential of the lithium determines the cell voltage. Most of the thin films used in current commercial variations of this thin film battery are deposited in vacuum chambers by RF and DC magnetron sputtering and by thermal evaporation onto unheated substrates. In addition, many publications report exploring a variety of other physical and chemical vapor deposition processes, such as pulsed laser deposition, electron cyclotron resonance sputtering, and

  12. Thin film device applications

    CERN Document Server

    Kaur, Inderjeet

    1983-01-01

    Two-dimensional materials created ab initio by the process of condensation of atoms, molecules, or ions, called thin films, have unique properties significantly different from the corresponding bulk materials as a result of their physical dimensions, geometry, nonequilibrium microstructure, and metallurgy. Further, these characteristic features of thin films can be drasti­ cally modified and tailored to obtain the desired and required physical characteristics. These features form the basis of development of a host of extraordinary active and passive thin film device applications in the last two decades. On the one extreme, these applications are in the submicron dimensions in such areas as very large scale integration (VLSI), Josephson junction quantum interference devices, magnetic bubbles, and integrated optics. On the other extreme, large-area thin films are being used as selective coatings for solar thermal conversion, solar cells for photovoltaic conver­ sion, and protection and passivating layers. Ind...

  13. Quantitative film radiography

    International Nuclear Information System (INIS)

    Devine, G.; Dobie, D.; Fugina, J.; Hernandez, J.; Logan, C.; Mohr, P.; Moss, R.; Schumacher, B.; Updike, E.; Weirup, D.

    1991-01-01

    We have developed a system of quantitative radiography in order to produce quantitative images displaying homogeneity of parts. The materials that we characterize are synthetic composites and may contain important subtle density variations not discernible by examining a raw film x-radiograph. In order to quantitatively interpret film radiographs, it is necessary to digitize, interpret, and display the images. Our integrated system of quantitative radiography displays accurate, high-resolution pseudo-color images in units of density. We characterize approximately 10,000 parts per year in hundreds of different configurations and compositions with this system. This report discusses: the method; film processor monitoring and control; verifying film and processor performance; and correction of scatter effects

  14. Min Morfars Film

    DEFF Research Database (Denmark)

    Juel, Henrik

    1957-01-01

    Reflektioner over filmhistoriebegrebet og gennemgang af konkrete filmoplevelser i 1957 og i nutiden med udgangspunkt i mødet med en gammel familiefilm. Reflektioner over valg af motiver i en social- og personhistorisk dateret film.......Reflektioner over filmhistoriebegrebet og gennemgang af konkrete filmoplevelser i 1957 og i nutiden med udgangspunkt i mødet med en gammel familiefilm. Reflektioner over valg af motiver i en social- og personhistorisk dateret film....

  15. Architecture and Film

    OpenAIRE

    Mohammad Javaheri, Saharnaz

    2016-01-01

    Film does not exist without architecture. In every movie that has ever been made throughout history, the cinematic image of architecture is embedded within the picture. Throughout my studies and research, I began to see that there is no director who can consciously or unconsciously deny the use of architectural elements in his or her movies. Architecture offers a strong profile to distinguish characters and story. In the early days, films were shot in streets surrounde...

  16. Anthropology of Film

    Directory of Open Access Journals (Sweden)

    Ivan Kovačević

    2017-08-01

    Full Text Available The second volume of the journal in 2017, which is part of the thematic issue, includes foreign films, and five of the eight papers contribute analyses of dystopian films. These are: A Clockwork Orange (1971, Westworld (1973, Gattaca (1997 The Lobster (2015 and Man and Chicken (2015. Aside from this thematic block, the first part of the thematic issue comprises the analyses of Miracolo a Milano (1951, Happiness (1998 and American Gangster (2007.

  17. Isodose curves through films

    International Nuclear Information System (INIS)

    Moura, A.M.S.; Campos, J.C.F. de; Scaff, L.A.M.; Val Kopacek, A.B. do

    1985-01-01

    Information about the beam profile of 4 MV X-rays through irradiation of radiographic films is presented. The films were irradiated in parallel to the central axis, within tissue-like phantom and in conditions of clinical application. The conclusion is that the method does not supply absolute values of percentage depth dose over points outside of beam bounds, but throughout the corrections it may be of great utility in radiation dosimetry. (Author) [pt

  18. Isodose curves through films

    Energy Technology Data Exchange (ETDEWEB)

    Moura, A.M.S.; Campos, J.C.F. de; Scaff, L.A.M.; Val Kopacek, A.B. do

    Information about the beam profile of 4 MV X-rays through irradiation of radiographic films is presented. The films were irradiated in parallel to the central axis, within tissue-like phantom and in conditions of clinical application. The conclusion is that the method does not supply absolute values of percentage depth dose over points outside of beam bounds, but throughout the corrections it may be of great utility in radiation dosimetry. (Author).

  19. Thin film tritium dosimetry

    Science.gov (United States)

    Moran, Paul R.

    1976-01-01

    The present invention provides a method for tritium dosimetry. A dosimeter comprising a thin film of a material having relatively sensitive RITAC-RITAP dosimetry properties is exposed to radiation from tritium, and after the dosimeter has been removed from the source of the radiation, the low energy electron dose deposited in the thin film is determined by radiation-induced, thermally-activated polarization dosimetry techniques.

  20. Innovative polyimide film

    International Nuclear Information System (INIS)

    Yaro, L.

    1988-01-01

    This paper reports on a new type of polyimide film with a unique chemical structure. Developed using proprietary technology, Upilex features outstanding properties over a wide range of temperatures, and offers the following advantages over previously available polyimide film: ultra-high heat resistance, excellent cryogenic properties, high tensile strength and modulus, excellent radiation resistance, excellent weather resistance (ultraviolet), superior dimensional stability, excellent chemical resistance, low water absorption, and low gas permeability

  1. Equilibrium helium film in the thick film limit

    International Nuclear Information System (INIS)

    Klier, J.; Schletterer, F.; Leiderer, P.; Shikin, V.

    2003-01-01

    For the thickness of a liquid or solid quantum film, like liquid helium or solid hydrogen, there exist still open questions about how the film thickness develops in certain limits. One of these is the thick film limit, i.e., the crossover from the thick film to bulk. We have performed measurements in this range using the surface plasmon resonance technique and an evaporated Ag film deposited on glass as substrate. The thickness of the adsorbed helium film is varied by changing the distance h of the bulk reservoir to the surface of the substrate. In the limiting case, when h > 0, the film thickness approaches about 100 nm following the van der Waals law in the retarded regime. The film thickness and its dependence on h is precisely determined and theoretically modeled. The equilibrium film thickness behaviour is discussed in detail. The agreement between theory and experiment is very good

  2. Radiochromic film dosimetry

    International Nuclear Information System (INIS)

    Soares, Christopher G.

    2006-01-01

    The object of this paper is to give a new user some practical information on the use of radiochromic films for medical applications. While various aspects of radiochromic film dosimetry for medical applications have been covered in some detail in several other excellent review articles which have appeared in the last few years [Niroomand-Rad, A., Blackwell, C.R., Coursey, B.M., Gall, K.P., McLaughlin, W.L., Meigooni, A.S., Nath, R., Rodgers, J.E., Soares, C.G., 1998. Radiochromic dosimetry: recommendations of the AAPM Radiation Therapy Committee Task Group 55. Med. Phys. 25, 2093-2115; Dempsey, J.F., Low, D.A., Mutic, S., Markman, J., Kirov, A.S., Nussbaum, G.H., Williamson, J.F., 2000. Validation of a precision radiochromic film dosimetry system for quantitative two-dimensional imaging of acute exposure dose distributions. Med. Phys. 27, 2462-2475; Butson, M.J., Yu, P.K.N., Cheung, T., Metcalfe, P., 2003. Radiochromic film for medical radiation dosimetry. Mater. Sci. Eng. R41, 61-120], it is the intent of the present author to present material from a more user-oriented and practical standpoint. That is, how the films work will be stressed much less than how to make the films work well. The strength of radiochromic films is most evident in applications where there is a very high dose gradient and relatively high absorbed dose rates. These conditions are associated with brachytherapy applications, measurement of small fields, and at the edges (penumbra regions) of larger fields

  3. Thin films and nanomaterials

    International Nuclear Information System (INIS)

    Jayakumar, S.; Kannan, M.D.; Prasanna, S.

    2012-01-01

    The objective of this book is to disseminate the most recent research in Thin Films, Nanomaterials, Corrosion and Metallurgy presented at the International Conference on Advanced Materials (ICAM 2011) held in PSG College of Technology, Coimbatore, India during 12-16 December 2011. The book is a compilation of 113 chapters written by active researchers providing information and critical insights into the recent advancements that have taken place. Important new applications are possible today in the fields of microelectronics, opto-electronics, metallurgy and energy by the application of thin films on solid surfaces. Recent progress in high vacuum technology and new materials has a remarkable effect in thin film quality and cost. This has led to the development of new single or multi-layered thin film devices with diverse applications in a multitude of production areas, such as optics, thermal barrier coatings and wear protections, enhancing service life of tools and to protect materials against thermal and atmospheric influence. On the other hand, thin film process techniques and research are strongly related to the basic research activities in nano technology, an increasingly important field with countless opportunities for applications due to the emergence of new properties at the nanoscale level. Materials and structures that are designed and fabricated at the nano scale level, offer the potential to produce new devices and processes that may enhance efficiencies and reduce costs in many areas, as photovoltaic systems, hydrogen storage, fuel cells and solar thermal systems. In the book, the contributed papers are classified under two sections i) thin films and ii) nanomaterials. The thin film section includes single or multi layer conducting, insulating or semiconducting films synthesized by a wide variety of physical or chemical techniques and characterized or analyzed for different applications. The nanomaterials section deals with novel or exciting materials

  4. Film beyond boundaries: film, migrant narratives and other media

    OpenAIRE

    Anelise Reich Corseuil

    2006-01-01

    The articles here presented are representative of the debates about the various transformational aspects of film studies, fostering the discussion about the transformations and interactions between national and international narrative forms, the interrelations between film and literature, and film with other media. The critical perspectives here presented range from an emphasis on cultural materialism, dialogism, reception theory, deconstructionism, narrative studies to film aesthetics or fil...

  5. Filming eugenics: teaching the history of eugenics through film.

    Science.gov (United States)

    Ooten, Melissa; Trembanis, Sarah

    2007-01-01

    In teaching eugenics to undergraduate students and general public audiences, film should he considered as a provocative and fruitful medium that can generate important discussions about the intersections among eugenics, gender, class, race, and sexuality. This paper considers the use of two films, A Bill of Divorcement and The Lynchburg Story, as pedagogical tools for the history of eugenics. The authors provide background information on the films and suggestions for using the films to foster an active engagement with the historical eugenics movement.

  6. Gammel Sherlock Holmes-film fundet - igen

    DEFF Research Database (Denmark)

    Lauridsen, Palle Schantz

    2017-01-01

    Om genfunden af en forsvundet Sherlock Holmes-film fra 1911, produceret af Nordisk Films Kompagni......Om genfunden af en forsvundet Sherlock Holmes-film fra 1911, produceret af Nordisk Films Kompagni...

  7. Film Propaganda: Ikonografi Kekuasaan

    Directory of Open Access Journals (Sweden)

    Budi Irawanto

    2004-07-01

    Full Text Available As a modern technological invention cinema has numerous potentialities such as economic, social and political power. Fascist regimes as well as film corporations have employed cinema as a tool of propaganda to control and mobilize the masses for the sake of their power longevity. Moreover, the character of film itself is a perfect fascist medium which came from the network of proto-fascism of the twentieth century civilization. By using various genres of Indonesian cinema from different eras as a case study, this article argues that Indonesian propaganda films have monolithic representation which can be described as a cult of "bapakisme" (patronism, "kultur komando" (command culture, marginalisation of women' role in Indonesian revolutionary movement and demonization of progressive women organisation, and glorification of the role of Soeharto in Indonesian revolutionary movement.

  8. Influence of film dimensions on film droplet formation.

    Science.gov (United States)

    Holmgren, Helene; Ljungström, Evert

    2012-02-01

    Aerosol particles may be generated from rupturing liquid films through a droplet formation mechanism. The present work was undertaken with the aim to throw some light on the influence of film dimensions on droplet formation with possible consequences for exhaled breath aerosol formation. The film droplet formation process was mimicked by using a purpose-built device, where fluid films were spanned across holes of known diameters. As the films burst, droplets were formed and the number and size distributions of the resulting droplets were determined. No general relation could be found between hole diameter and the number of droplets generated per unit surface area of fluid film. Averaged over all film sizes, a higher surface tension yielded higher concentrations of droplets. Surface tension did not influence the resulting droplet diameter, but it was found that smaller films generated smaller droplets. This study shows that small fluid films generate droplets as efficiently as large films, and that droplets may well be generated from films with diameters below 1 mm. This has implications for the formation of film droplets from reopening of closed airways because human terminal bronchioles are of similar dimensions. Thus, the results provide support for the earlier proposed mechanism where reopening of closed airways is one origin of exhaled particles.

  9. Buy, Borrow, or Steal? Film Access for Film Studies Students

    Science.gov (United States)

    Rodgers, Wendy

    2018-01-01

    Libraries offer a mix of options to serve the film studies curriculum: streaming video, DVDs on Reserve, and streaming DVDs through online classrooms. Some professors screen films and lend DVDs to students. But how do students obtain the films required for their courses? How would they prefer to do so? These are among the questions explored using…

  10. Radiographic film cassette unloading apparatus

    International Nuclear Information System (INIS)

    Stievenart, E.F.; Plessers, H.S.; Neujens, G.J.

    1980-01-01

    Apparatus for unloading cassettes, containing exposed radiographic films, has means for unfastening the cassettes, an inclined pathway for gravity feeding and rotating feed members (rollers or belts) to propel the films into the processor. (UK)

  11. Partnervalg på film

    DEFF Research Database (Denmark)

    Kramer, Mette

    2006-01-01

    Nye kognitions- og evolutionspsykologiske aspekter på kvinders filmpræferencer for romantiske film og melodramer......Nye kognitions- og evolutionspsykologiske aspekter på kvinders filmpræferencer for romantiske film og melodramer...

  12. Thin film metal-oxides

    CERN Document Server

    Ramanathan, Shriram

    2009-01-01

    Presents an account of the fundamental structure-property relations in oxide thin films. This title discusses the functional properties of thin film oxides in the context of applications in the electronics and renewable energy technologies.

  13. Optical thin film deposition

    International Nuclear Information System (INIS)

    Macleod, H.A.

    1979-01-01

    The potential usefulness in the production of optical thin-film coatings of some of the processes for thin film deposition which can be classified under the heading of ion-assisted techniques is examined. Thermal evaporation is the process which is virtually universally used for this purpose and which has been developed to a stage where performance is in almost all respects high. Areas where further improvements would be of value, and the possibility that ion-assisted deposition might lead to such improvements, are discussed. (author)

  14. Thin Film Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Zweibel, K.

    1998-11-19

    The motivation to develop thin film technologies dates back to the inception of photovoltaics. It is an idea based on achieving truly low-cost photovoltaics appropriate for mass production and energy significant markets. The key to the idea is the use of pennies worth of active materials. Since sunlight carries relatively little energy in comparison with combustion-based energy sources, photovoltaic (PV) modules must be cheap to produce energy that can be competitive. Thin films are presumed to be the answer to that low-cost requirement. But how cheap do they have to be? The following is an oversimplified analysis that allows some insight into this question.

  15. Oxidation films morphology

    International Nuclear Information System (INIS)

    Paidassi, J.

    1960-01-01

    After studying the oxidation of several pure polyvalent metals (Fe, Cu, Mn, Ni, U) and of their oxides at high temperature and atmospheric pressure, the author suggests how to modify the usual representation of the oxide film (a piling of different oxide layers, homogeneous on a micrographic scale with a equi-axial crystallisation, free of mechanical tensions, with flat boundary surfaces) to have it nearer to reality. In this first part, the author exposes the study of the real micrographic structure of the oxidation film and gives examples of precipitation in the oxides during the cooling of the oxidised sample. (author) [fr

  16. Films and nursing education

    Directory of Open Access Journals (Sweden)

    María GABRIELA FELIPPA

    2016-01-01

    Full Text Available The purpose of this paper is to provide some ideas about the importance of film, with it’s audiovisual narrative, in the nursing education. The use of films during teaching gives the posibility to increase the construction of a professional view.The nursing carreer of Isalud University of Argentina is founded a sistematic work with cinematographic support. In this case are presented different ways of work with cinematographic support in a curricular space of Fundamentals of Nursing of the career of a professional Nurse of the Isalud University.

  17. Superconducting Electronic Film Structures

    Science.gov (United States)

    1991-02-14

    Segmuller, A., Cooper, E.I., Chisholm, M.F., Gupta, A. Shinde, S., and Laibowitz, R.B. Lanthanum gallate substrates for epitaxial high-T superconducting thin...M. F. Chisholm, A. Gupta, S. Shinde, and R. B. Laibowitz, " Lanthanum Gallate Substrates for Epitaxial High-T c Superconducting Thin Films," Appl...G. Forrester and J. Talvacchio, " Lanthanum Copper Oxide Buffer Layers for Growth of High-T c Superconductor Films," Disclosure No. RDS 90-065, filed

  18. Storyboarding an Animated Film

    DEFF Research Database (Denmark)

    Frølunde, Lisbeth

    2009-01-01

    This paper applies notions of transformation to the analysis of data on semiotic processes related to making an animated film. The data derives from a study conducted in an upper secondary school in Copenhagen with students (18 years old) participating in a week-long workshop. The paper applies...... the concept of transduction with a focus on film storyboards: how students transform ideas when working with different modes (audio, visual) of representation. Data includes discourse analysis of semiotic processes and texts, referring to Social Semiotics and the methodology of Mediated Discourse Analysis...

  19. Intellectual Video Filming

    DEFF Research Database (Denmark)

    Juel, Henrik

    in favour of worthy causes. However, it is also very rewarding to draw on the creativity, enthusiasm and rapidly improving technical skills of young students, and to guide them to use video equipment themselves for documentary, for philosophical film essays and intellectual debate. In the digital era......Like everyone else university students of the humanities are quite used to watching Hollywood productions and professional TV. It requires some didactic effort to redirect their eyes and ears away from the conventional mainstream style and on to new and challenging ways of using the film media...

  20. Superconducting oxypnictide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Reisner, Andreas; Kidszun, Martin; Reich, Elke; Holzapfel, Bernhard; Schultz, Ludwig; Haindl, Silvia [IFW Dresden, Institute of Metallic Materials (Germany); Thersleff, Thomas [Uppsala University, Angstrom Laboratory (Sweden)

    2012-07-01

    We present an overview on the oxypnictide thin film preparation. So far, only LaAlO{sub 3} (001) single crystalline substrates provided a successful growth using pulsed laser deposition in combination with a post annealing process. Further experiments on the in-situ deposition will be reported. The structure of the films was investigated by X-ray diffractometry and transmission electron microscopy. Transport properties were measured with different applied fields to obtain a magnetic phase diagram for this new type of superconductor.

  1. Mechanics of Thin Films

    Science.gov (United States)

    1992-02-06

    and the second geometry was that of squat cylinders (diameter 6.4 mm, height 6.4 mm). These two geometries were tested in thermal shock tests, and a...milder [13]. More recently, Lau, Rahman and stressa nce ntrati, tha n films of lmalla rat ve spc Delale calculated the free edge singularity for stress...thickness of 3 mm); the second geometry was that As an example of the shielding effect of thin films, we of squat cylinders (diameter 6.4 mm, height 6.4

  2. Den umulige film

    DEFF Research Database (Denmark)

    Moestrup, Steffen Damkjær

    2014-01-01

    Den smertelige Sorg og Glæde fuldender en lang og glorværdig karriere for danske Nils Malmros. Den er en yderst vellykket film, fordi den forbliver usentimental om en skæbnesvanger dag i instruktørens liv.......Den smertelige Sorg og Glæde fuldender en lang og glorværdig karriere for danske Nils Malmros. Den er en yderst vellykket film, fordi den forbliver usentimental om en skæbnesvanger dag i instruktørens liv....

  3. Thin film ceramic thermocouples

    Science.gov (United States)

    Gregory, Otto (Inventor); Fralick, Gustave (Inventor); Wrbanek, John (Inventor); You, Tao (Inventor)

    2011-01-01

    A thin film ceramic thermocouple (10) having two ceramic thermocouple (12, 14) that are in contact with each other in at least on point to form a junction, and wherein each element was prepared in a different oxygen/nitrogen/argon plasma. Since each element is prepared under different plasma conditions, they have different electrical conductivity and different charge carrier concentration. The thin film thermocouple (10) can be transparent. A versatile ceramic sensor system having an RTD heat flux sensor can be combined with a thermocouple and a strain sensor to yield a multifunctional ceramic sensor array. The transparent ceramic temperature sensor that could ultimately be used for calibration of optical sensors.

  4. NMR characterization of thin films

    Science.gov (United States)

    Gerald II, Rex E.; Klingler, Robert J.; Rathke, Jerome W.; Diaz, Rocio; Vukovic, Lela

    2010-06-15

    A method, apparatus, and system for characterizing thin film materials. The method, apparatus, and system includes a container for receiving a starting material, applying a gravitational force, a magnetic force, and an electric force or combinations thereof to at least the starting material, forming a thin film material, sensing an NMR signal from the thin film material and analyzing the NMR signal to characterize the thin film of material.

  5. Film beyond boundaries: film, migrant narratives and other media Film beyond boundaries: film, migrant narratives and other media

    OpenAIRE

    Anelise Reich Corseuil

    2008-01-01

    The articles here presented are representative of the debates about the various transformational aspects of film studies, fostering the discussion about the transformations and interactions between national and international narrative forms, the interrelations between film and literature, and film with other media. The critical perspectives here presented range from an emphasis on cultural materialism, dialogism, reception theory, deconstructionism, narrative studies to film aesthetics or fil...

  6. Antikken på film

    DEFF Research Database (Denmark)

    Krasilnikoff, Jens

    2012-01-01

    Review af forskning om den græsk-romerske oldtid på film. Dertil en skitse til videre arbejde med antikken på film ud fra et historiefagligt og kulturhistorisk udgangspunkt.......Review af forskning om den græsk-romerske oldtid på film. Dertil en skitse til videre arbejde med antikken på film ud fra et historiefagligt og kulturhistorisk udgangspunkt....

  7. NMR characterization of thin films

    Science.gov (United States)

    Gerald, II, Rex E.; Klingler, Robert J.; Rathke, Jerome W.; Diaz, Rocio; Vukovic, Lela

    2008-11-25

    A method, apparatus, and system for characterizing thin film materials. The method, apparatus, and system includes a container for receiving a starting material, applying a gravitational force, a magnetic force, and an electric force or combinations thereof to at least the starting material, forming a thin film material, sensing an NMR signal from the thin film material and analyzing the NMR signal to characterize the thin film of material.

  8. Rare Earth Oxide Thin Films

    CERN Document Server

    Fanciulli, Marco

    2007-01-01

    Thin rare earth (RE) oxide films are emerging materials for microelectronic, nanoelectronic, and spintronic applications. The state-of-the-art of thin film deposition techniques as well as the structural, physical, chemical, and electrical properties of thin RE oxide films and of their interface with semiconducting substrates are discussed. The aim is to identify proper methodologies for the development of RE oxides thin films and to evaluate their effectiveness as innovative materials in different applications.

  9. Film in Education: This Worked For Me.

    Science.gov (United States)

    Breen, Myles P.

    Several techniques for teaching film appreciation to adults are discussed, including the use of audio cassettes, instructional films, silent films, and film dissection. Included are the techniques, philosophy, and content of a seminar on the short film, in which the short film is viewed as a variant of a short story, a pop song, a joke, and a…

  10. Radical Pedagogy, Prison, and Film

    Science.gov (United States)

    O'Neill, Dierdre

    2015-01-01

    This article explores the work of The Inside Film project. Inside Film works with a specific group of people (prisoners and ex-prisoners) in a particular set of circumstances (in prison or on parole) exploring how film making can be used within prison education or with people who have been to prison as a means of fostering a critical engagement…

  11. Film Analysis through Linguistic Base

    Science.gov (United States)

    Tanriverdi, Belgin

    2007-01-01

    Studies made in the last few years show that using films in language classrooms is an effective way in teaching a foreign language. Well-chosen films can serve as a valuable pedagogical aid, both for classroom use and self-study. This article is about using films in language classrooms through a specially designed course, whose outline description…

  12. Diamond films: Historical perspective

    Energy Technology Data Exchange (ETDEWEB)

    Messier, R. [Pennsylvania State Univ., University Park (United States)

    1993-01-01

    This section is a compilation of notes and published international articles about the development of methods of depositing diamond films. Vapor deposition articles are included from American, Russian, and Japanese publications. The international competition to develop new deposition methodologies is stressed. The current status of chemical vapor deposition of diamond is assessed.

  13. The magnetohydrodynamic squeeze film

    International Nuclear Information System (INIS)

    Hamza, E.A.

    1987-06-01

    The motion of an electrically conducting fluid film squeezed between two parallel disks in the presence of a magnetic field applied perpendicular to the disks is studied. Analytic solutions through use of a regular perturbation scheme are obtained. The results show that the electromagnetic forces increase the load carrying capacity considerably. (author). 5 refs, 10 figs, 3 tabs

  14. A Film Canister Colorimeter.

    Science.gov (United States)

    Gordon, James; James, Alan; Harman, Stephanie; Weiss, Kristen

    2002-01-01

    A low-cost, low-tech colorimeter was constructed from a film canister. The student-constructed colorimeter was used to show the Beer-Lambert relationship between absorbance and concentration and to calculate the value of the molar absorptivity for permanganate at the wavelength emission maximum for an LED. Makes comparisons between this instrument…

  15. FILM I KUFFERTEN

    DEFF Research Database (Denmark)

    Johansen, Stine Liv; Hansen, Adriana Maria

    2013-01-01

    kulturen, medierne er i kulturen – også i legekulturen. Denne rapport beskriver og undersøger et særligt eksempel på medialiseret leg. På baggrund af feltstudier i fem danske børnehaver, hvor et nyt filmpædagogisk materiale – Film i Kufferten - introduceres, er det rapportens formål at eksemplificere...

  16. Filmens krop, kroppens film

    DEFF Research Database (Denmark)

    Moestrup, Steffen Damkjær

    2014-01-01

    Vi har i nyere tid set en lind strøm af dokumentarfilm, der iscenesætter afvigende kroppe. Det gælder film som Shape of the Shapeless (2010), Herbstgold (2010), Beating Time (2010), Planet of Snail (2011), Whole (2003) og Kinbaku – the Art of Bondage (2009). Fælles for filmene er, at de dels...

  17. History, Memory and Film

    DEFF Research Database (Denmark)

    Bondebjerg, Ib

    In this paper I discuss history and memory from a theoretical and philosophical point of view and the non-fiction and fiction aspects of historical representation. I use Edgar Reitz’ monumental work Heimat 1-3 (and his recent film Die Andere Heimat) as examples of very different transformative...

  18. Our Favorite Film Shocks

    DEFF Research Database (Denmark)

    Willerslev, Rane; Suhr, Christian

    2014-01-01

    The modern medium of film has long been hailed for its capacity for producing shocks of an entertaining, thought-provoking, or even politically emancipative nature. But what is a shock, how and when does it occur, how long does it last, and are there particular techniques for producing cinematic...

  19. Intercultural Training with Films

    Science.gov (United States)

    Roell, Christine

    2010-01-01

    Films are a great medium to use not only to practice English, but also to facilitate intercultural learning. Today English is a global language spoken by people from many countries and cultural backgrounds. Since culture greatly impacts communication, it is helpful for teachers to introduce lessons and activities that reveal how different…

  20. "Gudbai, Lenin!" - film goda

    Index Scriptorium Estoniae

    2003-01-01

    Euroopa Filmiakadeemia tänavused auhinnasaajad : Saksa film "Good bye, Lenin!" võitis 6 auhinda, kaasaarvatud parima filmi tiitel. Parim režissöör - Lars von Trier "Dogville'i" eest, aasta üllatus - Andrei Zvjagintsevi "Tagasitulek"

  1. Introduction to Film.

    Science.gov (United States)

    Burns, Gary

    There are numerous ways to structure the introduction to film course so as to meet the needs of the different types of students who typically enroll. Assuming there is no production component in the course, the teacher is left with two major approaches to choose from--historical and aesthetic. The units in the course will typically be built around…

  2. Korupsi dalam Film Indonesia

    Directory of Open Access Journals (Sweden)

    Rhafidilla Vebrynda

    2015-01-01

    Full Text Available Abstract: Corruption has been rooted and institutionalized in our smallest environment. The campaign to fight corruption comes from various organizations through numerous varieties of means. This study looks at the Komisi Pemberantasan Korupsi (KPK campaign through a film entitled “Kita Versus Korupsi”. This study uses narrative analysis by looking at the elements of narrative, narrative structure, the analysis model of aktan and the Greimas’ semiotic square. It is found that the film narrates corruption as trouble and resistor. The various forms of corruption are narrated using the combination of techniques scene, dialogue and flashback. Abstrak: Korupsi sudah mengakar dan melembaga hingga lingkungan terkecil kita. Kampanye untuk melawannya datang dari berbagai pihak melalui beragam sarana. Penelitian ini melihat kampanye Komisi Pemberantasan Korupsi (KPK melalui film “Kita Versus Korupsi”. Menggunakan metode analisis naratif dengan melihat unsur naratif, struktur naratif, analisis model aktan dan oposisi segi empat Algirdas Greimas, penelitian ini menemukan bahwa korupsi dinarasikan sebagai gangguan dan penghambat. Film tersebut selalu menghadapkan pelaku korupsi dengan pihak yang tidak korupsi secara langsung. Latar belakang pengetahuan tokoh utama tentang korupsi berpengaruh dalam pengambilan keputusannya. Berbagai bentuk korupsi dinarasikan dengan teknik penggabungan scene, dialog dan flashback.

  3. Film o Heraklicie

    OpenAIRE

    Tytko, Marek Mariusz

    1987-01-01

    Tekst jest wierszem metafizycznym o relacji człowieka ze światem na przykładzie filozofii Heraklita i manipulacji filmowej. The text is a metaphysical verse on relationship a man and the world for example philosophy of Heraclitus and film manipulation.

  4. Film selection in medical radiology

    International Nuclear Information System (INIS)

    Bor, Dogan

    1988-01-01

    Importing of medical imaging films is the responsibility of Turkish Red Croscend, but some institutions have currently started to import their own films. Because of the different resources in individual departments throughout Turkey, a general purpose medical film is imported by Turkish Red Croscend. This kind of film has the advantage to tolerate some technical faults related to the exposure, dark room and processing conditions and still reveals the necessary image quality. In addition to general purpose film, many companies produce special used films which improve some film characteristics in order to have a better image. The initial results of a project already started by Turkish Atomic Energy Authority showed that some other technical reasons prevent obtaining films with optimum quality. The film is the last step of diagnostic procedure and not only gives necessary clinical information, but also visualizes all the problems related to the lock of the calibration of X-ray system and dark room processing conditions. Because of these reasons, many people hold the film responsible for every technical problem. During the selection of the best film among the different companies, institutions have to fulfill some prerequisites at the beginning and than evaluate the quantitative results obtained from measurements according to their clinical purposes. It is the subject of this paper to show how to use film parameter as a comparison to different types of films measured with light sensitometry method. The dark room and processing problems which adversely effect the results are also given. The requirements for the best film selection both for general and special purposes are also evaluated. The extent of this paper is limited only to films using radiology and does not cover the types used in other imaging areas

  5. Ion beam assisted film growth

    CERN Document Server

    Itoh, T

    2012-01-01

    This volume provides up to date information on the experimental, theoretical and technological aspects of film growth assisted by ion beams.Ion beam assisted film growth is one of the most effective techniques in aiding the growth of high-quality thin solid films in a controlled way. Moreover, ion beams play a dominant role in the reduction of the growth temperature of thin films of high melting point materials. In this way, ion beams make a considerable and complex contribution to film growth. The volume will be essential reading for scientists, engineers and students working in thi

  6. Handbook of thin film technology

    CERN Document Server

    Frey, Hartmut

    2015-01-01

    “Handbook of Thin Film Technology” covers all aspects of coatings preparation, characterization and applications. Different deposition techniques based on vacuum and plasma processes are presented. Methods of surface and thin film analysis including coating thickness, structural, optical, electrical, mechanical and magnetic properties of films are detailed described. The several applications of thin coatings and a special chapter focusing on nanoparticle-based films can be found in this handbook. A complete reference for students and professionals interested in the science and technology of thin films.

  7. Professor Camillo Negro's Neuropathological Films.

    Science.gov (United States)

    Chiò, Adriano; Gianetto, Claudia; Dagna, Stella

    2016-01-01

    Camillo Negro, Professor in Neurology at the University of Torino, was a pioneer of scientific film. From 1906 to 1908, with the help of his assistant Giuseppe Roasenda and in collaboration with Roberto Omegna, one of the most experienced cinematographers in Italy, he filmed some of his patients for scientific and educational purposes. During the war years, he continued his scientific film project at the Military Hospital in Torino, filming shell-shocked soldiers. In autumn 2011, the Museo Nazionale del Cinema, in partnership with the Faculty of Neurosciences of the University of Torino, presented a new critical edition of the neuropathological films directed by Negro. The Museum's collection also includes 16 mm footage probably filmed in 1930 by Doctor Fedele Negro, Camillo's son. One of these films is devoted to celebrating the effects of the so-called "Bulgarian cure" on Parkinson's disease.

  8. Host thin films incorporating nanoparticles

    Science.gov (United States)

    Qureshi, Uzma

    The focus of this research project was the investigation of the functional properties of thin films that incorporate a secondary nanoparticulate phase. In particular to assess if the secondary nanoparticulate material enhanced a functional property of the coating on glass. In order to achieve this, new thin film deposition methods were developed, namely use of nanopowder precursors, an aerosol assisted transport technique and an aerosol into atmospheric pressure chemical vapour deposition system. Aerosol assisted chemical vapour deposition (AACVD) was used to deposit 8 series of thin films on glass. Five different nanoparticles silver, gold, ceria, tungsten oxide and zinc oxide were tested and shown to successfully deposit thin films incorporating nanoparticles within a host matrix. Silver nanoparticles were synthesised and doped within a titania film by AACVD. This improved solar control properties. A unique aerosol assisted chemical vapour deposition (AACVD) into atmospheric pressure chemical vapour deposition (APCVD) system was used to deposit films of Au nanoparticles and thin films of gold nanoparticles incorporated within a host titania matrix. Incorporation of high refractive index contrast metal oxide particles within a host film altered the film colour. The key goal was to test the potential of nanopowder forms and transfer the suspended nanopowder via an aerosol to a substrate in order to deposit a thin film. Discrete tungsten oxide nanoparticles or ceria nanoparticles within a titanium dioxide thin film enhanced the self-cleaning and photo-induced super-hydrophilicity. The nanopowder precursor study was extended by deposition of zinc oxide thin films incorporating Au nanoparticles and also ZnO films deposited from a ZnO nanopowder precursor. Incorporation of Au nanoparticles within a VO: host matrix improved the thermochromic response, optical and colour properties. Composite VC/TiC and Au nanoparticle/V02/Ti02 thin films displayed three useful

  9. Silk Film Embossing System

    Science.gov (United States)

    Paquette, Mark S.

    New tools are often required to facilitate new discoveries and test new methods. Commercial offerings can be prohibitively expensive and difficult to customize. The development of ad-hoc tools provides the most flexibility and provides an opportunity to modify and refine a technology. An embossing system was developed for silk film imprinting and stamping in order to facilitate and add versatility to the efforts involving micro- and nanoscale device manufacturing in biopolymers. This system features temperature controlled embossing surfaces, adjustable embossing pressures, and variable embossing times. The device can also be fitted with interchangeable temperature controlled embossing and stamping tools. The design, development, fabrication, applications, and future improvements are explored for the system. This device may facilitate new discoveries in the realm of biopolymer micro- and nanomanufacturing and may provide a path towards high volume production of silk film based technologies.

  10. Reading through Films

    Directory of Open Access Journals (Sweden)

    Madhavi Gayathri Raman

    2016-02-01

    Full Text Available This paper captures the design of a comprehensive curriculum incorporating the four skills based exclusively on the use of parallel audio-visual and written texts. We discuss the use of authentic materials to teach English to Indian undergraduates aged 18 to 20 years. Specifically, we talk about the use of parallel reading (screen-play and audio-visual texts (Shawshank Redemption, and Life is Beautiful, A Few Good Men and Lion King drawn from popular culture in the classroom as an effective teaching medium. Students were gradually introduced to films based on novels with extracts from the original texts (Schindler’s List, Beautiful Mind for extended reading and writing practice. We found that students began to pay more attention to aspects such as pronunciation, intonational variations, discourse markers and vocabulary items (phrasal verbs, synonyms, homophones, and puns. Keywords: Reading, films, popular culture, ESL classroom, language skills

  11. Strategic Talk in Film.

    Science.gov (United States)

    Payr, Sabine; Skowron, Marcin; Dobrosovestnova, Anna; Trapp, Martin; Trappl, Robert

    2017-01-01

    Conversational robots and agents are being designed for educational and/or persuasive tasks, e.g., health or fitness coaching. To pursue such tasks over a long time, they will need a complex model of the strategic goal, a variety of strategies to implement it in interaction, and the capability of strategic talk. Strategic talk is incipient ongoing conversation in which at least one participant has the objective of changing the other participant's attitudes or goals. The paper is based on the observation that strategic talk can stretch over considerable periods of time and a number of conversational segments. Film dialogues are taken as a source to develop a model of the strategic talk of mentor characters. A corpus of film mentor utterances is annotated on the basis of the model, and the data are interpreted to arrive at insights into mentor behavior, especially into the realization and sequencing of strategies.

  12. Polyether ether ketone film. Polyether ether ketone film

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, S. (Sumitomo Chemical Co. Ltd., Tokyo (Japan))

    1990-07-05

    The characteristics and the film making process of polyether ether ketone (PEEK) resin, and the characteristics and the applications of PEEK film, are described. PEEK is aromatic polyketone with super thermal resistance. Though it is a crystalline polymer of which the crystallinity is controlled to 48% in a highest degree, it has also amorphous property, thus it shows unique property. The characteristics of PEEK resin are found in thermal resistance, incombusti-bility, transparency, chemical resistance, light resistance and radiation resistance. As for the film making process, casting method by T-die is generally adopted. The general properties of PEEK film are excellent in high thermal resistance, good electrical properties, chemical resistance, hydrolysis resistance, radiation resistance and imcombusti-bility. In the application of PEEK film, new development is expected in following fields; a high performance composite, flexible print substrate with high thermal resistance, insulating tape with thermal resistance, and a general film in the nuclear energy industry. 5 figs., 5 tabs.

  13. Thin film processes

    CERN Document Server

    Vossen, John L

    1978-01-01

    Remarkable advances have been made in recent years in the science and technology of thin film processes for deposition and etching. It is the purpose of this book to bring together tutorial reviews of selected filmdeposition and etching processes from a process viewpoint. Emphasis is placed on the practical use of the processes to provide working guidelines for their implementation, a guide to the literature, and an overview of each process.

  14. Darwinisme, film og filmteori

    DEFF Research Database (Denmark)

    Grodal, Torben Kragh

    2010-01-01

    Artiklen giver først en oversigt over evolutionshistorisk baseret kulturanalyse og dennes tilknytning til neuropsykologi, herunder evolutionsteoretiske studier af religion og andre overnaturlige forestillingssystemer. Derefter redegøres der kort for, hvorledes Darwinismen har  stødt på modstand, ...... kulturhistoriske baggrund for retssag og film.   Keywords: evolutionsteori, filmteori, evolutionær religionsanalyse, Inherit the wind.     Udgivelsesdato: april 2010...

  15. Ellipsometry of anodic film growth

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.G.

    1978-08-01

    An automated computer interpretation of ellisometer measurements of anodic film growth was developed. Continuous mass and charge balances were used to utilize more fully the time dependence of the ellipsometer data and the current and potential measurements. A multiple-film model was used to characterize the growth of films which proceeds via a dissolution--precipitation mechanism; the model also applies to film growth by adsorption and nucleation mechanisms. The characteristic parameters for film growth describe homogeneous and heterogeneous crystallization rates, film porosities and degree of hydration, and the supersaturation of ionic species in the electrolyte. Additional descriptions which may be chosen are patchwise film formation, nonstoichiometry of the anodic film, and statistical variations in the size and orientation of secondary crystals. Theories were developed to describe the optical effects of these processes. An automatic, self-compensating ellipsometer was used to study the growth in alkaline solution of anodic films on silver, cadmium, and zinc. Mass-transport conditions included stagnant electrolyte and forced convection in a flow channel. Multiple films were needed to characterize the optical properties of these films. Anodic films grew from an electrolyte supersatuated in the solution-phase dissolution product. The degree of supersaturation depended on transport conditions and had a major effect on the structure of the film. Anodic reaction rates were limited by the transport of charge carriers through a primary surface layer. The primary layers on silver, zinc, and cadmium all appeared to be nonstoichiometric, containing excess metal. Diffusion coefficients, transference numbers, and the free energy of adsorption of zinc oxide were derived from ellipsometer measurements. 97 figures, 13 tables, 198 references.

  16. Polymer Thin Film Stabilization.

    Science.gov (United States)

    Costa, A. C.; Oslanec, R.; Composto, R. J.; Vlcek, P.

    1998-03-01

    We study the dewetting dynamics of thin polystyrene (PS) films deposited on silicon oxide surfaces using optical (OM) and atomic force (AFM) microscopes. Quantitative analysis of the hole diameter as a function of annealing time at 175^oC shows that blending poly(styrene-block-methyl-methacrylate) (PS-b-PMMA) with PS acts to dramatically slow down the dewetting rate and even stops holes growth before they impinge. AFM studies show that the hole floor is smooth for a pure PS film but contains residual polymer for the blend. At 5% vol., a PS-b-PMMA with high molar mass and low PMMA is a more effective stabilizing agent than a low molar mass/high PMMA additive. The optimum copolymer concentration is 3% vol. beyond which film stability doesn't improve. Although dewetting is slowed down relative to pure PS, PS/PS-b-PMMA bilayers dewet at a faster rate than blends having the same overall additive concentration.

  17. Automatic film loader for X-ray spot film device

    International Nuclear Information System (INIS)

    1975-01-01

    A light tight tunnel extends over the top of a diagnostic X-ray table. A film cassette is mounted for reciprocating in the tunnel between an X-ray exposure position and a position in which the cassette is unloaded or loaded with film automatically. Unexposed films are dispensed one at a time into the cassette from a feed magazine at one end of the tunnel. After exposure, the film is ejected from the cassette into a receiving magazine at the same end of the tunnel. (Auth.)

  18. FOREIGN LANGUAGE FILMS IN LOUISIANA DEPOSITORIES.

    Science.gov (United States)

    BABINEAUX, AUDREY

    THIS MANUAL IS AN ANNOTATED LIST OF 16-MILLIMETER EDUCATIONAL FOREIGN LANGUAGE FILMS (BOTH LINGUISTIC AND CULTURAL) WHICH WERE PURCHASED WITH STATE AND FEDERAL FUNDS AND PLACED IN LOUISIANA'S NINE FILM LIBRARIES. FILMS ARE ARRANGED ALPHABETICALLY BY LANGUAGES. FILMS IN THE TARGET LANGUAGE ARE LISTED SEPARATELY FROM FILMS WITH ENGLISH NARRATION. A…

  19. Olympic Training Film Profiles. Volume III.

    Science.gov (United States)

    1971

    Approximately 250 instructional films are described in Volume Three (1970-1971) of this review. After an introduction which considers film discussions from the instructor's point of view and offers some ideas for conducting a film showing and ordering the films, profiles of the films are presented grouped under such areas as management…

  20. Silent Film in the German Classroom.

    Science.gov (United States)

    Caldwell, David

    In addition to using films in the German classroom to introduce students to German culture and history, it is important to show and study the film as film. This procedure emphasizes the importance of the film as a part of creative arts in Germany and demands student participation in observation and discussion. Many German silent films are…

  1. Film-screen digital radiography

    International Nuclear Information System (INIS)

    Schwenker, R.P.; Eger, H.

    1985-01-01

    The excellent performance of the digital film-screen system as a receptor for projection radiographic data is discussed. An experimental system for obtaining high quality digital radiographic data by laser scanning radiographic films is described. This system is being used to evaluate the clinical utility of various digital image processing algorithms. Future plans include an investigation of quantitative analysis of projection radiographic data. Digital data obtained by film scanning can be used with digital image archiving and communications systems. (author)

  2. Thin-film solar cells

    International Nuclear Information System (INIS)

    Aberle, Armin G.

    2009-01-01

    The rapid progress that is being made with inorganic thin-film photovoltaic (PV) technologies, both in the laboratory and in industry, is reviewed. While amorphous silicon based PV modules have been around for more than 20 years, recent industrial developments include the first polycrystalline silicon thin-film solar cells on glass and the first tandem solar cells based on stacks of amorphous and microcrystalline silicon films ('micromorph cells'). Significant thin-film PV production levels are also being set up for cadmium telluride and copper indium diselenide.

  3. Film Editing Handbook; Technique of 16mm Film Cutting.

    Science.gov (United States)

    Churchill, Hugh B.

    Designed to help the film student with the complexities of 16mm film cutting, this handbook catalogs the mechanical procedures of both picture and sound cutting and supplies step-by-step explanations of these procedures. Because the handbook was organized so that it could be used while working at the cutting bench, common cutting problems and…

  4. "Kuleshov on Film": A Spectator-Centered Film Theory.

    Science.gov (United States)

    Curran, Trisha

    This paper describes some of the theories of cinematography of Soviet film theorist and filmmaker Lev Kuleshov. It points out that for him, film was communication portraying people's activities emanating from the environment. It explains that he was especially interested in audience response, particularly that of the proletariat, and that he felt…

  5. Nuclear power in films

    International Nuclear Information System (INIS)

    Marth, H.

    1977-01-01

    The model film seminar consists of 4 parts: the first one deals with the technology of NPPs, the various reactor types and their fuel cycles; based on this, safety problems and environmental effects of NPPs during routine operation and in incidents as well as the working conditions in the atomic industry are dealt with. The second field of topics covers the 'Atomic industry complex' with the aim of illustrating governmental atomic energy promotion and the economic interests of the atomic industry; in this context, the role played by atomic energy in energy supply and economic growth are reflected on critically, too. In the third complex of topics resistance against NPPs is reported on; this includes the various forms of resistance, the motives of the people concerned, and the perspectives of the anti-NPP-movement. Alternatives to atomic energy are dealt with in the fourth group of topics. Here, ways to save energy and to use it in a more rational way are presented, as well as non-nuclear alternatives (solar, wind, geothermal energy etc.) and the fusion reactor as an alternative to the present fission reactors. Chapter 5 contains didactics-methodical information on the use of the various media and on planning and organizing events of this kind. This chapter was afterwards taken into the brochure. It deals with the experiences and impulses of the first model film seminar in Berlin. The filmography with comments contains the most important films on atomic energy problems as far as they are available easily. (orig./HP) [de

  6. [Oral films as perspective dosage form].

    Science.gov (United States)

    Walicová, Veronika; Gajdziok, Jan

    Oral films, namely buccal mucoadhesive films and orodispersible films represent innovative formulations for administration of a wide range of drugs. Oral films show many advantageous properties and are intended for systemic drug delivery or for local treatment of the oral mucosa. In both cases, the film represents a thin layer, which could be intended to adhere to the oral mucosa by means of mucoadhesion; or to rapid dissolution and subsequent swallowing without the need of liquid intake, in the case of orodispersible films. Main constitutive excipients are film-forming polymers, which must in the case of mucoadhesive forms remain on the mucosa within the required time interval. Oral films are currently available on the pharmaceutical market and could compete with conventional oral dosage forms in the future. oral cavity oral films buccal mucoadhesive films orodispersible films film-forming polymers.

  7. Film scoring today - Theory, practice and analysis

    OpenAIRE

    Flach, Paula Sophie

    2012-01-01

    This thesis considers film scoring by taking a closer look at the theoretical discourse throughout the last decades, examining current production practice of film music and showcasing a musical analysis of the film Inception (2010).

  8. Microstructure of Thin Films

    Science.gov (United States)

    1990-02-07

    Proceedings, Thin film Technologies II, 652, 256-263, (1986) B. Schmitt, J.P. Borgogno, G. Albrand and E. Pelletier, "In situ and air index measurements...34 SPIE Proceedings, "Optical Components and Systems", 805, 128 (1987) 11 B. Schmitt, J.P. Borgogno, G. Albrand and E. Pelletier. "In situ and air index...aT , m..a, lot,, o ,,f,02,d I4 k -1-1..... autocovariance lengths, less than 0.5 um, indicate that , 514n, ob0 o p’,Ofclllc....,,o,,oy0,1- agua sblrt

  9. Towards the Possible Film

    OpenAIRE

    Dawood, S.

    2014-01-01

    Towards the Possible Film is a study in parallel universes – and the sparks that fly when worlds collide. As much of a projection into a far-off future as a flashback to a long-forgotten past, Dawood’s vivid 20-minute tableau combines the resonance of a mythic fable with the hallucinatory haziness of a waking dream. Emerging from the waves, as if transported from another dimension, two blue-skinned astronauts materialise on a red-rocked shoreline (Sidi Ifni in Southern Morocco). Blinking into...

  10. Falling Liquid Films

    CERN Document Server

    Kalliadasis, S; Scheid, B

    2012-01-01

    This research monograph gives a detailed review of the state-of-the-art theoretical methodologies for the analysis of dissipative wave dynamics and pattern formation on the surface of a film falling down a planar, inclined substrate. This prototype is an open-flow hydrodynamic instability representing an excellent paradigm for the study of complexity in active nonlinear media with energy supply, dissipation and dispersion. Whenever possible, the link between theory and experiments is illustrated and the development of order-of-magnitude estimates and scaling arguments is used to facilitate the

  11. Radiation grafting on natural films

    Science.gov (United States)

    Lacroix, M.; Khan, R.; Senna, M.; Sharmin, N.; Salmieri, S.; Safrany, A.

    2014-01-01

    Different methods of polymer grafting using gamma irradiation are reported in the present study for the preparation of newly functionalized biodegradable films, and some important properties related to their mechanical and barrier properties are described. Biodegradable films composed of zein and poly(vinyl alcohol) (PVA) were gamma-irradiated in presence of different ratios of acrylic acid (AAc) monomer for compatibilization purpose. Resulting grafted films (zein/PVA-g-AAc) had their puncture strength (PS=37-40 N mm-1) and puncture deformation (PD=6.5-9.8 mm) improved for 30% and 50% PVA in blend, with 5% AAc under 20 kGy. Methylcellulose (MC)-based films were irradiated in the presence of 2-hydroxyethyl methacrylate (HEMA) or silane, in order to determine the effect of monomer grafting on the mechanical properties of films. It was found that grafted films (MC-g-HEMA and MC-g-silane) using 35% monomer performed higher mechanical properties with PS values of 282-296 N mm-1 and PD of 5.0-5.5 mm under 10 kGy. Compatibilized polycaprolactone (PCL)/chitosan composites were developed via grafting silane in chitosan films. Resulting trilayer grafted composite film (PCL/chitosan-g-silane/PCL) presented superior tensile strength (TS=22 MPa) via possible improvement of interfacial adhesion (PCL/chitosan) when using 25% silane under 10 kGy. Finally, MC-based films containing crystalline nanocellulose (CNC) as a filling agent were prepared and irradiated in presence of trimethylolpropane trimethacrylate (TMPTMA) as a grafted plasticizer. Grafted films (MC-g-TMPTMA) presented superior mechanical properties with a TS of 47.9 MPa and a tensile modulus (TM) of 1792 MPa, possibly due to high yield formation of radicals to promote TMPTMA grafting during irradiation. The addition of CNC led to an additional improvement of the barrier properties, with a significant 25% reduction of water vapor permeability (WVP) of grafted films.

  12. Fire resistant films for aircraft applications

    Science.gov (United States)

    Kourtides, D. A.

    1983-01-01

    Alternative sandwich panel decorative films were investigated as replacements for the polyvinyl fluoride currently used in aircraft interiors. Candidate films were studied for flammability, smoke emission, toxic gas emission, flame spread, and suitability as a printing surface for the decorative acrylic ink system. Several of the candidate films tested were flame modified polyvinyl fluoride, polyvinylidene fluoride, polyimide, polyamide, polysulfone, polyphenylsulfone, polyethersulfone, polybenzimidazole, polycarbonate, polyparabanic acid, polyphosphazene, polyetheretherketon, and polyester. The films were evaluated as pure films only, films silk-screened with an acrylic ink, and films adhered to a phenolic fiberglass substrate. Films which exhibited the highest fire resistant properties included PEEK polyetheretherketon, Aramid polyamide, and ISO-BPE polyester.

  13. Predicting film genres with implicit ideals

    Directory of Open Access Journals (Sweden)

    Andrew McGregor Olney

    2013-01-01

    Full Text Available We present a new approach to defining film genre based on implicit ideals. When viewers rate the likability of a film, they indirectly express their ideal of what a film should be. Across six studies we investigate the category structure that emerges from likability ratings and the category structure that emerges from the features of film. We further compare these data-driven category structures with human annotated film genres. We conclude that film genres are structured more around ideals than around features of film. This finding lends experimental support to the notion that film genres are set of shifting, fuzzy, and highly contextualized psychological categories.

  14. Organized organic ultrathin films fundamentals and applications

    CERN Document Server

    Ariga, Katsuhiko

    2012-01-01

    This handy reference is the first comprehensive book covering both fundamentals and recent developments in the field with an emphasis on nanotechnology. Written by a highly regarded author in the field, the book details state-of-the-art preparation, characterization and applications of thin films of organic molecules and biomaterials fabricated by wet processes and also highlights applications in nanotechnology The categories of films covered include monomolecular films (monolayers) both on a water surface and on a solid plate, Langmuir-Blodgett films (transferred multilayer films on a solid plate from a water surface), layer-by-layer films (adsorbed multilayer films on a solid support), and spontaneously assembled films in solution.

  15. Electrical initiation of an energetic nanolaminate film

    Science.gov (United States)

    Tringe, Joseph W.; Gash, Alexander E.; Barbee, Jr., Troy W.

    2010-03-30

    A heating apparatus comprising an energetic nanolaminate film that produces heat when initiated, a power source that provides an electric current, and a control that initiates the energetic nanolaminate film by directing the electric current to the energetic nanolaminate film and joule heating the energetic nanolaminate film to an initiation temperature. Also a method of heating comprising providing an energetic nanolaminate film that produces heat when initiated, and initiating the energetic nanolaminate film by directing an electric current to the energetic nanolaminate film and joule heating the energetic nanolaminate film to an initiation temperature.

  16. More than films and dragon awards

    DEFF Research Database (Denmark)

    Redvall, Eva Novrup

    2012-01-01

    This article discusses how the largest film festival in the Nordic countries, the Göteborg International Film Festival (GIFF), is much more than a setting for bringing quality films to local audiences.With retrospectives, an extensive programme of seminars and master classes, a film lab for upcom......This article discusses how the largest film festival in the Nordic countries, the Göteborg International Film Festival (GIFF), is much more than a setting for bringing quality films to local audiences.With retrospectives, an extensive programme of seminars and master classes, a film lab...

  17. Beryllium thin films for resistor applications

    Science.gov (United States)

    Fiet, O.

    1972-01-01

    Beryllium thin films have a protective oxidation resistant property at high temperature and high recrystallization temperature. However, the experimental film has very low temperature coefficient of resistance.

  18. Predicting film genres with implicit ideals.

    Science.gov (United States)

    Olney, Andrew McGregor

    2012-01-01

    We present a new approach to defining film genre based on implicit ideals. When viewers rate the likability of a film, they indirectly express their ideal of what a film should be. Across six studies we investigate the category structure that emerges from likability ratings and the category structure that emerges from the features of film. We further compare these data-driven category structures with human annotated film genres. We conclude that film genres are structured more around ideals than around features of film. This finding lends experimental support to the notion that film genres are set of shifting, fuzzy, and highly contextualized psychological categories.

  19. Radiographic film orientation in radiotherapy dosimetry

    International Nuclear Information System (INIS)

    Suchowerska, N.; Davison, A.; Drew, J.; Metcalfe, P.

    1996-01-01

    Since the discovery of x-rays, film has been used as a detection medium for radiation. More recently radiographic film has become established as a practical tool for the measurement of dose distribution in radiotherapy. The accuracy and reproducibility of film dosimetry depends on photon energy, processing conditions and film plane orientation. The relationship between photon energy, processing conditions and film dosimetry accuracy has been studied. The role of film plane orientation is still controversial. The current work aims to clarify the effects film plane orientation has on film dosimetry. Poster 205. (author)

  20. Feminist Film Theory and Criticism.

    Science.gov (United States)

    Mayne, Judith

    1985-01-01

    Discusses Laura Mulvey's 1975 essay, "Visual Pleasure and Narrative Cinema," and the ideas about feminist film theory and psychoanalysis as a critical tool which it raises. Suggests contradiction is the central issue in feminist film theory. Explores definitions of women's cinema. (SA)

  1. Thin films: Past, present, future

    Energy Technology Data Exchange (ETDEWEB)

    Zweibel, K

    1995-04-01

    This report describes the characteristics of the thin film photovoltaic modules necessary for an acceptable rate of return for rural areas and underdeveloped countries. The topics of the paper include a development of goals of cost and performance for an acceptable PV system, a review of current technologies for meeting these goals, issues and opportunities in thin film technologies.

  2. Light scattering by soap films

    NARCIS (Netherlands)

    Vrij, A.

    A theory is constructed describing the scattering from a liquid film (e.g., a soap film) of a light beam polarized normal to the plane of incidence. This scattering is due to the small irregular corrugations caused by thermal motion. The interference of the reflected incident beam with its multiple

  3. Thin-film solar cell

    NARCIS (Netherlands)

    Metselaar, J.W.; Kuznetsov, V.I.

    1998-01-01

    The invention relates to a thin-film solar cell provided with at least one p-i-n junction comprising at least one p-i junction which is at an angle alpha with that surface of the thin-film solar cell which collects light during operation and at least one i-n junction which is at an angle beta with

  4. Thin-film photovoltaic technology

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, R.N. [National Renewable Energy Laboratory, Golden, CO (United States)

    2010-07-01

    The high material and processing costs associated with single-crystal and polycrystalline silicon wafers that are commonly used in photovoltaic cells render these modules expensive. This presentation described thin-film solar cell technology as a promising alternative to silicon solar cell technology. Cadmium telluride (CdTe) thin films along with copper, indium, gallium, and selenium (CIGS) thin films have become the leaders in this field. Their large optical absorption coefficient can be attributed to a direct energy gap that allows the use of thin layers (1-2 {mu}m) of active material. The efficiency of thin-film solar cell devices based on CIGS is 20 per cent, compared to 16.7 per cent for thin-film solar cell devices based on CdTe. IBM recently reported an efficiency of 9.7 per cent for a new type of inorganic thin-film solar cell based on a Cu{sub 2}ZnSn(S, Se){sub 4} compound. The efficiency of an organic thin-film solar cell is 7.9 per cent. This presentation included a graph of PV device efficiencies and discussed technological advances in non-vacuum deposited, CIGS-based thin-film solar cells. 1 fig.

  5. Size effects in thin films

    CERN Document Server

    Tellier, CR; Siddall, G

    1982-01-01

    A complete and comprehensive study of transport phenomena in thin continuous metal films, this book reviews work carried out on external-surface and grain-boundary electron scattering and proposes new theoretical equations for transport properties of these films. It presents a complete theoretical view of the field, and considers imperfection and impurity effects.

  6. On almost inviscid film flows

    NARCIS (Netherlands)

    Kuiken, H.K.

    1970-01-01

    This study is concerned with flow of liquid films down inclined plates, which carry an increasing amount of fluid in the downstream direction. It is supposed that by some mechanism, e.g. condensation, the fluid enters the film at its outer edge. The rate at which this mass-addition occurs is

  7. The Public Library Film Redefined.

    Science.gov (United States)

    Peltier, Euclid

    1978-01-01

    An historical discussion of three types of film--teaching, information, and entertainment--is presented. The numbers of films in each category, especially the last, which includes the animated, unnarrated, iconographic, underground, and avant-garde, has grown substantially. Libraries have quickly accepted all except the revolutionary philosophies…

  8. Improved Dielectric Films For Capacitors

    Science.gov (United States)

    Yen, Shiao-Ping S.; Lewis, Carol R.; Cygan, Peter J.; Jow, T. Richard

    1994-01-01

    Dielectric films made from blends of some commercially available high-dielectric-constant cyanoresins with each other and with cellulose triacetate (CTA) have both high dielectric constants and high breakdown strengths. Dielectric constants as high as 16.2. Films used to produce high-energy-density capacitors.

  9. Partner selection and Hollywood Films

    DEFF Research Database (Denmark)

    Grodal, Torben Kragh; Kramer, Mette

    2012-01-01

    Based on cognitive, neurological and evolutionary based film theory the article describes the representation of partner selection in Hollywood films. It analyses paradigm scenarios of partner selection and love, It further describes some of those mechanisms that regulate the relation between...

  10. Cinemabilia; Catalogue of Film Literature.

    Science.gov (United States)

    Cinemabilia, New York, NY.

    The catalog lists and briefly annotates more than 3,500 current, second-hand, and out-of-print books about film that are available from Cinemabilia, New York City. The catalog is divided into 37 categories. The section on special genre lists works on horror, science fiction, Westerns, and Tarzan films, ranging from "Drums of Fu-Manchu" to "Movie…

  11. Radiation grafting on natural films

    International Nuclear Information System (INIS)

    Lacroix, M.; Khan, R.; Senna, M.; Sharmin, N.; Salmieri, S.; Safrany, A.

    2014-01-01

    Different methods of polymer grafting using gamma irradiation are reported in the present study for the preparation of newly functionalized biodegradable films, and some important properties related to their mechanical and barrier properties are described. Biodegradable films composed of zein and poly(vinyl alcohol) (PVA) were gamma-irradiated in presence of different ratios of acrylic acid (AAc) monomer for compatibilization purpose. Resulting grafted films (zein/PVA-g-AAc) had their puncture strength (PS=37–40 N mm −1 ) and puncture deformation (PD=6.5–9.8 mm) improved for 30% and 50% PVA in blend, with 5% AAc under 20 kGy. Methylcellulose (MC)-based films were irradiated in the presence of 2-hydroxyethyl methacrylate (HEMA) or silane, in order to determine the effect of monomer grafting on the mechanical properties of films. It was found that grafted films (MC-g-HEMA and MC-g-silane) using 35% monomer performed higher mechanical properties with PS values of 282–296 N mm −1 and PD of 5.0–5.5 mm under 10 kGy. Compatibilized polycaprolactone (PCL)/chitosan composites were developed via grafting silane in chitosan films. Resulting trilayer grafted composite film (PCL/chitosan-g-silane/PCL) presented superior tensile strength (TS=22 MPa) via possible improvement of interfacial adhesion (PCL/chitosan) when using 25% silane under 10 kGy. Finally, MC-based films containing crystalline nanocellulose (CNC) as a filling agent were prepared and irradiated in presence of trimethylolpropane trimethacrylate (TMPTMA) as a grafted plasticizer. Grafted films (MC-g-TMPTMA) presented superior mechanical properties with a TS of 47.9 MPa and a tensile modulus (TM) of 1792 MPa, possibly due to high yield formation of radicals to promote TMPTMA grafting during irradiation. The addition of CNC led to an additional improvement of the barrier properties, with a significant 25% reduction of water vapor permeability (WVP) of grafted films. - Highlights: • Irradiation of zein

  12. Film dosimetry in conformal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Danciu, C; Proimos, B S [Patras Univ. (Greece). Dept. of Medical Physics

    1995-12-01

    Dosimetry, through a film sandwiched in a transverse cross-section of a solid phantom, is a method of choice in Conformal Radiotherapy because: (a) the blackness (density) of the film at each point offers a measure of the total dose received at that point, and (b) the film is easily calibrated by exposing a film strip in the same cross-section, through a stationary field. The film must therefore have the following properties: (a) it must be slow, in order not to be overexposed, even at a therapeutic dose of 200 cGy, and (b) the response of the film (density versus dose curve) must be independent of the photon energy spectrum. A few slow films were compared. It was found that the Kodak X-Omat V for therapy verification was the best choice. To investigate whether the film response was independent of the photon energy, response curves for six depths, starting from the depth of maximum dose to the depth of 25 cm, in solid phantom were derived. The vertical beam was perpendicular to the anterior surface of the phantom, which was at the distance of 100 cm from the source and the field was 15x15 cm at that distance. This procedure was repeated for photon beams emitted by a Cobalt-60 unit, two 6 MV and 15 MV Linear Accelerators, as well as a 45 MV Betatron. For each of those four different beams the film response was the same for all six depths. The results, as shown in the diagrams, are very satisfactory. The response curve under a geometry similar to that actually applied, when the film is irradiated in a transverse cross-section of the phantom, was derived. The horizontal beam was almost parallel (angle of 85) to the plane of the film. The same was repeated with the central ray parallel to the film (angle 90) and at a distance of 1.5 cm from the horizontal film. The field size was again 15x15 at the lateral entrance surface of the beam. The response curves remained the same, as when the beam was perpendicular to the films.

  13. Surface electrons of helium films

    International Nuclear Information System (INIS)

    Studart, N.; Hipolito, O.

    1986-01-01

    Theoretical calculations of some properties of two-dimensional electrons on a liquid helium film adsorbed on a solid substrate are reviewed. We describe the spectrum of electron bound states on bulk helium as well on helium films. The correlational properties, such as the structure factor and correlation energy, are determined as functions of the film thickness for different types of substrates in the framework of a Generalized Random-Phase Approximation. The collective excitations of this system are also described. The results for electrons on the surface of thin films and bulk helium are easily obtained. we examine the electron interaction with the excitations of the liquid helium surface resulting in a new polaron state, which was observed very recently. The ground state energy and the effective mass of this polaron are determined by using the path-integral formalism and unitary-transformation method. Recent speculations about the phase diagram of electrons on the helium film are also discussed. (Author) [pt

  14. Viscous bursting of suspended films

    Science.gov (United States)

    Debrégeas, G.; Martin, P.; Brochard-Wyart, F.

    1995-11-01

    Soap films break up by an inertial process. We present here the first observations on freely suspended films of long-chain polymers, where viscous effects are dominant and no surfactant is present. A hole is nucleated at time 0 and grows up to a radius R(t) at time t. A surprising feature is that the liquid from the hole is not collected into a rim (as it is in soap films): The liquid spreads out without any significant change of the film thickness. The radius R(t) grows exponentially with time, R~exp(t/τ) [while in soap films R(t) is linear]. The rise time τ~ηe/2γ where η is viscosity, e is thickness (in the micron range), and γ is surface tension. A simple model is developed to explain this growth law.

  15. A new radiochromic dosimeter film

    Science.gov (United States)

    Sidney, L. N.; Lynch, D. C.; Willet, P. S.

    By employing acid-sensitive leuco dyes in a chlorine-containing polymer matrix, a new radiochromic dosimeter film has been developed for gamma, electron beam, and ultraviolet radiation. These dosimeter films undergo a color change from colorless to royal blue, red fuchsia, or black, depending on dye selection, and have been characterized using a visible spectrophotometer over an absorbed dose range of 1 to 100 kGy. The primary features of the film are improved color stability before and after irradiation, whether stored in the dark or under artificial lights, and improved moisture resistance. The effects of absorbed dose, dose rate, and storage conditions on dosimeter performance are discussed. The dosimeter material may be produced as a free film or coated onto a transparent substrate and optionally backed with adhesive. Potential applications for these materials include gamma sterilization indicator films for food and medical products, electron beam dosimeters, and in-line radiation monitors for electron beam and ultraviolet processing.

  16. Characterization of organic thin films

    CERN Document Server

    Ulman, Abraham; Evans, Charles A

    2009-01-01

    Thin films based upon organic materials are at the heart of much of the revolution in modern technology, from advanced electronics, to optics to sensors to biomedical engineering. This volume in the Materials Characterization series introduces the major common types of analysis used in characterizing of thin films and the various appropriate characterization technologies for each. Materials such as Langmuir-Blodgett films and self-assembled monolayers are first introduced, followed by analysis of surface properties and the various characterization technologies used for such. Readers will find detailed information on: -Various spectroscopic approaches to characterization of organic thin films, including infrared spectroscopy and Raman spectroscopy -X-Ray diffraction techniques, High Resolution EELS studies, and X-Ray Photoelectron Spectroscopy -Concise Summaries of major characterization technologies for organic thin films, including Auger Electron Spectroscopy, Dynamic Secondary Ion Mass Spectrometry, and Tra...

  17. Oxide ultrathin films science and technology

    CERN Document Server

    Pacchioni, Gianfranco

    2012-01-01

    A wealth of information in one accessible book. Written by international experts from multidisciplinary fields, this in-depth exploration of oxide ultrathin films covers all aspects of these systems, starting with preparation and characterization, and going on to geometrical and electronic structure, as well as applications in current and future systems and devices. From the Contents: Synthesis and Preparation of Oxide Ultrathin Films Characterization Tools of Oxide Ultrathin Films Ordered Oxide Nanostructures on Metal Surfaces Unusual Properties of Oxides and Other Insulators in the Ultrathin Limit Silica and High-K Dielectrics Thin Films in Microelectronics Oxide Passive Films and Corrosion Protection Oxide Films as Catalytic Materials and as Models of Real Catalysts Oxide Films in Spintronics Oxide Ultrathin Films in Solid Oxide Fuel Cells Transparent Conducting and Chromogenic Oxide Films as Solar Energy Materials Oxide Ultrathin Films in Sensor Applications Ferroelectricity in Ultrathin Film Capacitors T...

  18. Contributions of Film Introductions and Film Summaries to Learning from Instructional Films.

    Science.gov (United States)

    Lathrop, C. W., Jr.; Norford, C. A.

    An exploratory study of the contribution to learning of typical introductory and summarizing sequences in instructional films underlined the need for further experimental work to determine what kinds of introductory and concluding sequences are most useful in promoting learning from films. The first part of the study was concerned with film…

  19. Nutrition of grazing cattle in the Mid Rift Valley of Ethiopia: use of an improved n-alkane method to estimate nutrient intake

    NARCIS (Netherlands)

    Derseh, M.B.

    2013-01-01

    Nutrient intake is an important factor that determines the performance of production animals. In free ranging animals, direct measurement of nutrient intake is difficult to conduct, and it is frequently estimated indirectly by the aid of markers. The aim of this thesis was to investigate the

  20. Phase Equilibria of Mixtures Containing Glycol and n-Alkane: Experimental Study of Infinite Dilution Activity Coefficients and Modeling Using the Cubic-Plus-Association Equation of State

    DEFF Research Database (Denmark)

    Afzal, Waheed; Breil, Martin Peter; Théveneau, Pascal

    2009-01-01

    previously reported in the literature, along with the data measured in this work have been modeled using the cubic-plus-association (CPA) equation of state (EoS). Satisfactory results have been obtained using temperature-independent interaction parameters. Useful remarks are presented about the application...

  1. Solution properties of C60 and C70 fullerenes and C21 to C40 n-alkanes at infinite dilution in carbon dioxide from supercritical fluid chromatography

    Czech Academy of Sciences Publication Activity Database

    Roth, Michal; Maag, K.; Schneider, G. M.; Tuma, D.

    2001-01-01

    Roč. 105, č. 42 (2001), s. 10373-10378 ISSN 1089-5647 Institutional research plan: CEZ:AV0Z4031919 Keywords : thermodynamics Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.379, year: 2001

  2. Krichevskii parameters of heavy n-alkanes in carbon dioxide: comparison of the results from solubility measurements and from supercritical fluid chromatography

    Czech Academy of Sciences Publication Activity Database

    Roth, Michal

    2003-01-01

    Roč. 212, 1-2 (2003), s. 1-9 ISSN 0378-3812 R&D Projects: GA ČR GA203/02/1093; GA ČR GA203/02/0023 Institutional research plan: CEZ:AV0Z4031919 Keywords : dilute solution in supercritical solvent * partial molar volume * cubic equation of state Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.165, year: 2003

  3. Vapor phase nucleation of the short-chain n-alkanes (n-pentane, n-hexane and n-heptane): Experiments and Monte Carlo simulations

    Science.gov (United States)

    Ogunronbi, Kehinde E.; Sepehri, Aliasghar; Chen, Bin; Wyslouzil, Barbara E.

    2018-04-01

    We measured the nucleation rates of n-pentane through n-heptane in a supersonic nozzle at temperatures ranging from ca. 109 K to 168 K. For n-pentane and n-hexane, these are the first nucleation rate measurements that have been made, and the trends in the current data agree well with those in the earlier work of Ghosh et al. [J. Chem. Phys. 132, 024307 (2010)] for longer chain alkanes. Complementary Monte Carlo simulations, using the transferable potentials for phase equilibria-united atom potentials, suggest that despite the high degree of supercooling, the critical clusters remain liquid like under experimental conditions for n-pentane through n-heptane, but adopt more ordered structures for n-octane and n-nonane. For all three alkanes, the experimental and simulated nucleation rates are offset by ˜3 orders of magnitude when plotted as a function of ln S/(Tc/T - 1)1.5. Explicitly accounting for the surface tension difference between the real and model substances, or alternatively using the Hale [Phys. Rev. A 33, 4156 (1986); Metall. Mater. Trans. A 23, 1863 (1992)] scaling parameter, Ω, consistent with the model potential, increases the offset to ˜6 orders of magnitude.

  4. Effect of Size and Distribution of Ni Nanoparticles on γ-Al2O3 in Oleic Acid Hydrodeoxygenation to Produce n-Alkanes

    Directory of Open Access Journals (Sweden)

    Manuel Sánchez-Cárdenas

    2016-10-01

    Full Text Available To contribute to the search for an oxygen-free biodiesel from vegetable oil, a process based in the oleic acid hydrodeoxygenation over Ni/γ-Al2O3 catalysts was performed. In this work different wt % of Ni nanoparticles were prepared by wetness impregnation and tested as catalytic phases. Oleic acid was used as a model molecule for biodiesel production due to its high proportion in vegetable oils used in food and agro-industrial processes. A theoretical model to optimize yield of n-C17 was developed using size, distribution, and wt % of Ni nanoparticles (NPs as additional factors besides operational conditions such as temperature and reaction time. These mathematical models related to response surfaces plots predict a higher yield of n-C17 when physical parameters of Ni NPs are suitable. It can be of particular interest that the model components have a high interaction with operation conditions for the n-C17 yields, with the size, distribution, and wt % of Ni NPs being the most significant. A combination of these factors statistically pointed out those conditions that create a maximum yield of alkanes; these proved to be affordable for producing biodiesel from this catalytic environmental process.

  5. Partial Molar Volumes of Air-Component Gases in Several Liquid n-Alkanes and 1-Alkanols at 313.15 K

    Czech Academy of Sciences Publication Activity Database

    Izák, Pavel; Cibulka, I.; Heintz, A.

    1995-01-01

    Roč. 109, č. 2 (1995), s. 227-234 ISSN 0378-3812 Keywords : data density * partial molar volume * gas -liquid mixture Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.024, year: 1995

  6. INHIBITION OF GROWTH OF A GRAPHIUM SP. ON GASEOUS N-ALKANES BY GASEOUS N-ALKYNES AND N-ALKENES. (R825689C018)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  7. Using n-alkane records to constrain carbon cycle - hydrological cycle coupling: Case study from the Northern Hemisphere mid-latitudes during the PETM

    Science.gov (United States)

    Krishnan, S.; Pagani, M.; Tipple, B. J.

    2010-12-01

    The early Eocene was a warmer world compared to the present and is characterized by rising temperatures interspersed with rapid hyperthermal events. During the largest of these rapid warming events; the Paleocene-Eocene Thermal Maximum (PETM), proxy records suggest that sea surface temperatures (SST) rose by 3-5 deg. C in the tropics (Zachos et al., 2003, Tripati and Elderfield, 2004), >5 deg. C in the Arctic (Sluijs et al., 2006) and perhaps has high as 9 deg. C in some sub-Antarctic regions (Kennett and Stott, 1991; Thomas et al., 1999). This warming is believed to be the result of massive input of 13C-depleted carbon into the ocean-atmosphere system, evidenced by the large negative carbon isotope excursion (CIE) and carbonate dissolution associated with the event. However, there are several questions regarding the exact mechanism of warming and feedbacks between the carbon cycle and climate. Did climate shift prior to the main event that led to the release of isotopically light carbon? Do we observe consistent leads or lags between changes in carbon isotopes and hydrological conditions during warm intervals? This study aims to reconstruct hydrological changes in the in the Northern Hemisphere mid-latitudes during the PETM using terrestrial biomarkers. Terrestrial biomarkers, such leaf-wax lipids stored in sediments, have the unique advantage of recording carbon and hydrogen isotopic compositions of atmospheric CO2 (modified by plant fractionation) and precipitation (modified by plant fractionation and evapotranspiration), allowing evaluation of the relative timing of carbon and hydrogen isotopic (i.e., climate) shifts. In this study, we compile and present three mid-latitude PETM records from the Northern Hemisphere, i.e. Alamedilla (Spain), Cicogna and Forada (Italy). The Cicogna and Forada sections are located in the Belluno basin (~12 km apart). Preliminary results do not indicate any significant pre-excursion hydrogen isotope changes at Cicogna, while at Forada we observe a pre-excursion shift toward more positive values. Comparison of the mean-weighted isotopic trends (to account for vegetation changes) indicates that the carbon and hydrogen isotopic compositions shift simultaneously at the start of the CIE at Cicogna and Forada and remain coupled during the latter part of the recovery. However, the most depleted values in δD do not coincide with the most negative δ13C values, suggesting that the response time of the hydrological cycle was slower than the carbon isotopic excursion. The δD trends appear to diverge from δ13C records during the initial recovery period. This difference in response and response times between the initial perturbation and recovery enable us to constrain the timing and mechanism of feedbacks. A third section (Alamedilla), located at lower latitude, will be used to test these hypotheses. The timing and average magnitudes of δD changes at these three sites will be extrapolated to infer precipitation trends during the late Paleocene, peak PETM, and early Eocene for this region and will be useful for future data-model comparisons.

  8. Use of n-alkanes and long-chain alcohols as faecal markers to estimate diet composition on small ruminants grazing/browsing mountain grasslands

    OpenAIRE

    Magalhães, Rui José Ribeiro Ferreira de

    2018-01-01

    Knowledge on the grazing/browsing behaviour, especially diet selection, of the different domestic herbivorous species under diverse vegetation communities is of particular importance for the development and application of appropriate grazing management strategies that increase the efficiency of the utilization of the existing vegetation and, consequently, the sustainability of the animal production system. Plant-wax components, namely alkanes and long-chain alcohols (LCOH), have been suggeste...

  9. Film Presentation: Die Urknallmaschine

    CERN Multimedia

    Carolyn Lee

    2010-01-01

    Die Urknallmaschine, an Austrian film by Gerd Baldauf, narrated by Norbert Frischauf (Alpha Österreich - ORF, 2009).  In CERN’s gigantic complex particles are accelerated to almost the speed of light, brought to collision and made to divide into even smaller particles. Public opinion of CERN’s research is also divided. Sceptics fear that black holes may be created. Might the goal to study the origin of the world lead to its destruction? The Austrian researcher Norbert Frischauf worked at CERN for many years. With his guidance it is possible to explore the world’s largest research centre, get a glimpse of the fascinating work the scientists do there and take a crash course in particle physics. Die Urknallmaschine will be presented on Friday, 25 June from 13:00 to 14:00 in the Main Auditorium. Language: German

  10. Dispersed flow film boiling

    International Nuclear Information System (INIS)

    Andreani, M.; Yadigaroglu, G.

    1989-12-01

    Dispersed flow film boiling is the heat transfer regime that occurs at high void fractions in a heated channel. The way this transfer mode is modelled in the NRC computer codes (RELAP5 and TRAC) and the validity of the assumption and empirical correlations used is discussed. An extensive review of the theoretical and experimental work related with heat transfer to highly dispersed mixtures reveals the basic deficiencies of these models: the investigation refers mostly to the typical conditions of low rate bottom reflooding, since the simulation of this physical situation by the computer codes has often showed poor results. The alternative models that are available in the literature are reviewed, and their merits and limits are highlighted. The modification that could improve the physics of the models implemented in the codes are identified. (author) 13 figs., 123 refs

  11. Following and Filming Fibromyalgia

    DEFF Research Database (Denmark)

    Schøler, Maja; Blaakilde, Anne Leonora

    from FM comprises a very complex situation, difficult to grasp, and, unfit for the traditional Cartesian conceptualization. The reaction from the outside to the sufferer is therefore often: "But you look so good!" (Connotatively implying, how can you be in pain?) In response to the difficulties...... in at least 11 spots, she is diagnosed with FM. We will now show a video spot with a woman being tested by the tenderpoint-test. The woman performs pain reactions to 18 of the 18 tenderpoints and thereby suffers of Fibromyalgia at a severe level. Show film (2 min ca.) Method In order to study FM...... is to get both a sensitive and a discoursive knowledge about bodies in pain. The use of the video camera is the cinematic part of the fieldwork. During fieldwork the persons revealed that a most common reaction to having pain, being tired, or feeling dizzy or depressed, is to isolate and hide away from...

  12. Sputtered indium oxide films

    International Nuclear Information System (INIS)

    Gillery, F.H.

    1986-01-01

    A method is described for depositing on a substrate multiple layer films comprising at least one primary layer of a metal oxide and at least one primary layer of a metal other than the metal of the oxide layer. The improvement described here comprises improving the adhesion between the metal oxide and metal layers by depositing between the layers an intermediate metal-containing layer having an affinity for both the metal and metal oxide layers. An article of manufacture is described comprising a nonmetallic substrate, and deposited thereon in any order: a. at least one coating layer of metal; b. at least one coating layer of an oxide of a metal other than the metal of the metal layer; and c. deposited between the metal and metal oxide layers an intermediate metal-containing layer having an affinity for both the metal and metal oxide layers

  13. Radiochromic film and polarization effects

    International Nuclear Information System (INIS)

    Yu, P.K.N.; Cheung, T.; Butson, M.J.; Cancer Services, Wollongong, NSW; Inwood, D.

    2004-01-01

    Full text: A new high sensitivity radiochromic film has been tested for its polarization properties. Gafchromic HS film has been shown to produce a relatively small (less than 3%) variation in measured optical density measured at 660nm wavelength when the light source is fully linear polarized and the film is rotated through 360 deg angle. Similar variations are seen when the detector is linearly polarized. If both light source and detector is linearly polarised variations in measured optical density can reach 15% when the film is rotated through 360 deg angle. This seems to be due to a phase shift in polarised light caused by the radiochromic film resulting in the polarised light source becoming out of phase with the polarised detector. Gafchromic HS radiochromic film produces a minimal polarization response with varying angle of rotation however we recommend that a polarization test be performed on a densitometry system to establish the extent of its polarization properties before accuracy dosimetry is performed with radiochromic HS film. Copyright (2004) Australasian College of Physical Scientists and Engineers in Medicine

  14. Irradiation gamma on chitosan films

    Energy Technology Data Exchange (ETDEWEB)

    Mello, Luana Miranda Lopes de; Souza, Adriana Regia Marques de; Arthur, Valter, E-mail: lumilopes@hotmail.com, E-mail: drilavras@yahoo.com.br, E-mail: arthur@cena.usp.br [Universidade Federal do Tocantins (UFT), Palmas,TO (Brazil). Departmento de Ciencia e Tecnologia de Alimentos; Universidade Federal de Goias (UFGO), Goiania (Brazil). Departmento de Ciencia e Tecnologia de Alimentos; Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)

    2017-11-01

    Films are preformed structures, independent, that are used to wrap food after processing, increasing their shelf life and enhancing its bright and attractive appearance. They are prepared from biological materials as an alternative to the plastic synthetic containers to improve the quality of the environment. Chitosan is a biodegradable polymer composed of β-(1-4) linked D-glucosamine (deacetylated unit) and N-acetyl-D- glucosamine (acetylated unit). It is produced commercially by deacetylation of chitin, which is a structural component of the exoskeleton of crustaceans. She is able to form films and edible and/or biodegradable coatings. With the objective to evaluate the effect of different doses of gamma radiation (0, 5, 10 and 15 kGy) and chitosan concentrations (1 and 2%) in film properties, it was evaluated its optical, mechanical and morphological properties. The films were produced by casting. Irradiation did not affect the thickness of the films, but influenced its colors, increasing the tone of the film for a stronger yellowish color. This fact can be attributed to the increased concentration of C = O bonds of chitosan due to the breakdown of the chain reaction and the Maillard reaction. Irradiated films showed smoother surface and less rough, due to the degradation of the chitosan molecule and poor mechanical properties, not showing good flexibility and stretching. (author)

  15. Passive films at the nanoscale

    International Nuclear Information System (INIS)

    Maurice, Vincent; Marcus, Philippe

    2012-01-01

    Highlights: ► Nanoscale data on growth, structure and local properties of passive films reviewed. ► Preferential role of defects of passive films on the corrosion resistance emphasized. ► Effect of grain boundaries on local electronic properties shown by new data. ► Use of atomistic modeling to test mechanistic hypotheses illustrated. - Abstract: The nanometer scale chemical and structural aspects of ultrathin oxide passive films providing self-protection against corrosion to metals and alloys in aqueous environments are reviewed. Data on the nucleation and growth of 2D anodic oxide films, details on the atomic structure and nanostructure of 3D passive films, the preferential role of surface step edges in dissolution in the passive state and the preferential role of grain boundaries of the passive films in passivity breakdown are presented. Future perspectives are discussed, and exemplified by new data obtained on the relationship between the nanostructure of oxide passive films and their local electronic properties. Atomistic corrosion modeling by ab initio density functional theory (DFT) is illustrated by the example of interactions of chloride ions with hydroxylated oxide surfaces, including the role of surface step edges. Data obtained on well-defined substrate surfaces with surface analytical techniques are emphasized.

  16. Film repeats in radiology department

    International Nuclear Information System (INIS)

    Suwan, A. Z.; Al-Shakharah, A. I

    1997-01-01

    During a one year period, 4910 radiographs of 55780 films were repeated. The objective of our study was to analyse and to classify the causes in order to minimize the repeats, cut the expenses and to provide optimal radiographs for accurate diagnosis. Analysis of the different factors revealed that, 43.6% of film repeats in our service were due to faults in exposure factors, centering comprises 15.9% of the repeats, while too much collimation was responsible for 7.6% of these repeats. All of which can be decreased by awareness and programmed training of technicians. Film blurring caused by patient motion was also responsible for 4.9% for radiographs reexamination, which can be minimized by detailed explanation to the patient and providing the necessary privacy. Fogging of X-Ray films by improper storage or inadequate handling or processing faults were responsible for 14.5% in repeats in our study. Methods and criteria for proper storage and handling of films were discussed. Recommendation for using modern day-light and laser processor has been high lighted. Artefacts are noticeably high in our cases, due to spinal dresses and frequent usage of precious metals for c osmotic purposes in this part of the world. The repeated films comprise 8.8% of all films We conclude that, the main factor responsible for repeats of up to 81.6% of cases was the technologists, thus emphasizing the importance of adequate training of the technologists. (authors). 15 refs., 9 figs., 1 table

  17. Irradiation gamma on chitosan films

    International Nuclear Information System (INIS)

    Mello, Luana Miranda Lopes de; Souza, Adriana Regia Marques de; Arthur, Valter

    2017-01-01

    Films are preformed structures, independent, that are used to wrap food after processing, increasing their shelf life and enhancing its bright and attractive appearance. They are prepared from biological materials as an alternative to the plastic synthetic containers to improve the quality of the environment. Chitosan is a biodegradable polymer composed of β-(1-4) linked D-glucosamine (deacetylated unit) and N-acetyl-D- glucosamine (acetylated unit). It is produced commercially by deacetylation of chitin, which is a structural component of the exoskeleton of crustaceans. She is able to form films and edible and/or biodegradable coatings. With the objective to evaluate the effect of different doses of gamma radiation (0, 5, 10 and 15 kGy) and chitosan concentrations (1 and 2%) in film properties, it was evaluated its optical, mechanical and morphological properties. The films were produced by casting. Irradiation did not affect the thickness of the films, but influenced its colors, increasing the tone of the film for a stronger yellowish color. This fact can be attributed to the increased concentration of C = O bonds of chitosan due to the breakdown of the chain reaction and the Maillard reaction. Irradiated films showed smoother surface and less rough, due to the degradation of the chitosan molecule and poor mechanical properties, not showing good flexibility and stretching. (author)

  18. Computational simulation of radiographic film

    International Nuclear Information System (INIS)

    Goncalves, Elicardo A. de S.; Santos, Marcio H. dos; Anjos, Marcelino J.; Oliveira, Luis F. de

    2013-01-01

    The composition of a radiographic film gives its values of speed, spatial resolution and base density. The technical knowledge allows to predict how a film with a known composition works, and simulate how this film will work with changes in composition and exposure. In this paper, characterization of films composed by different emulsions was realized, in a way to know the characteristic curve, and to study how the format, organization and concentration of silver salt crystals set the radiographic film images.This work aims to increase an existing simulator, where parallel programming was used to simulate X-ray fluorescence processes. The setup of source and X-ray interactions with objects stills the same, and the detector constructed in this work was placed to form images. At first, considering the approach that the film is a square matrix where each element has a specific quantity of silver grains, that each grain fills a specific area, and that each interaction to radiation transforms a salt silver grain in to metallic silver grain (black grain), we have a blackening standard, and it should show how is the behavior of a optic density in a specific area of the film. Each matrix element has a degree of blackening, and it is proportional to the black grains area. (author)

  19. Electrostatic fluctuations in soap films

    International Nuclear Information System (INIS)

    Dean, D.S.; Horgan, R.R.

    2002-01-01

    A field theory to describe electrostatic interactions in soap films, described by electric multilayers with a generalized thermodynamic surface-charging mechanism, is studied. In the limit where the electrostatic interactions are weak, this theory is exactly soluble. The theory incorporates in a consistent way, the surface-charging mechanism and the fluctuations in the electrostatic field that correspond to the zero-frequency component of the van der Waals force. It is shown that these terms lead to a Casimir-like attraction that can be sufficiently large to explain the transition between the common black film to a Newton black film

  20. Interfaces and thin films physics

    International Nuclear Information System (INIS)

    Equer, B.

    1988-01-01

    The 1988 progress report of the Interfaces and Thin Film Physics laboratory (Polytechnic School France) is presented. The research program is focused on the thin films and on the interfaces of the amorphous semiconductor materials: silicon and silicon germanium, silicon-carbon and silicon-nitrogen alloys. In particular, the following topics are discussed: the basic processes and the kinetics of the reactive gas deposition, the amorphous materials manufacturing, the physico-chemical characterization of thin films and interfaces and the electron transport in amorphous semiconductors. The construction and optimization of experimental devices, as well as the activities concerning instrumentation, are also described [fr

  1. ZnO Film Photocatalysts

    Directory of Open Access Journals (Sweden)

    Bosi Yin

    2014-01-01

    Full Text Available We have synthesized high-quality, nanoscale ultrathin ZnO films at relatively low temperature using a facile and effective hydrothermal approach. ZnO films were characterized by scanning electron microscope (SEM, X-ray diffraction (XRD, Raman spectroscopy, photoluminescence spectra (PL, and UV-vis absorption spectroscopy. The products demonstrated 95% photodegradation efficiency with Congo red (CR after 40 min irradiation. The photocatalytic degradation experiments of methyl orange (MO and eosin red also were carried out. The results indicate that the as-obtained ZnO films might be promising candidates as the excellent photocatalysts for elimination of waste water.

  2. Preparation of thin vyns films

    International Nuclear Information System (INIS)

    Blanc, R.; Chedin, P.; Gizon, A.

    1965-01-01

    The fabrication of thin films of VYNS resin (copolymer of chloride and vinyl acetate) of superficial density from 3 to 50 μg/cm 2 with solutions in cyclohexanone is presented. Study and discussion of some properties compared with formvar film (polyvinyl formals). It appears that both can be used as source supports but formvar films are prepared more easily and more quickly, in addition they withstand higher temperatures. The main quality of VYNS is that they can be easily separated even several days after their preparation [fr

  3. Subjective Sexual Arousal to Films of Masturbation

    Science.gov (United States)

    Mosher, Donald L.; Abramson, Paul R.

    1977-01-01

    A film of a male or female masturbating was viewed by 96 males and 102 females. Males reported the highest level of sexual arousal to the female film and the lowest level of arousal to the male film. Females were sexually aroused by both films. (Author)

  4. Regional Film Culture: Challenges and Problems.

    Science.gov (United States)

    Fountain, Alan

    1978-01-01

    Discusses the relationship between general film culture and state intervention through the formation of a regional film policy and the funding of film exhibition, film education, and filmmaking in Britain. Suggests ways in which intervention can perpetuate the dominant cultural ideology and ways to identify, resist, and challenge present…

  5. Film Handbook. Communication Manual. 2nd Edition.

    Science.gov (United States)

    Beuthner, Reginald, Comp.; And Others

    Reference material is provided in this book for editors, producers, camera and sound technicians, others working in film, and film students. Each chapter is a self-contained unit about specific aspects of film-making, designed to accompany film courses being offered by the University of the West Indies, the Jamaica Broadcasting Corporation, and…

  6. Historians and Film: Some Problems and Prospects

    Science.gov (United States)

    O'Connor, John E.

    1973-01-01

    The growing interest towards using film in history classes and by historians developing a methodology for research into film is discussed in this article. Problems of using films for teachers focus on cost and poor quality. Difficulties for historical researchers concern the treatment of historical documents in film medium -- recording,…

  7. 16 CFR 501.1 - Camera film.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Camera film. 501.1 Section 501.1 Commercial... 500 § 501.1 Camera film. Camera film packaged and labeled for retail sale is exempt from the net... should be expressed, provided: (a) The net quantity of contents on packages of movie film and bulk still...

  8. Cultural Dependency in Canada's Feature Film Industry.

    Science.gov (United States)

    Pendakur, Manjunath

    1981-01-01

    Examines the ownership and policies of the dominant firms in the Canadian film market to explain Canada's dependence on imported films. Demonstrates how the economic relations existing between Canadian and U.S. film industries limit the profitability of films made in Canada. (JMF)

  9. Are Wildlife Films Really "Nature Documentaries"?

    Science.gov (United States)

    Bouse, Derek

    1998-01-01

    Examines origins of wildlife films. Outlines their tension between education and entertainment. Looks at how Disney codified wildlife films as a coherent genre by imposing conventionalized narrative frameworks upon them. Discusses factors influencing wildlife television in the 1990s. Concludes that wildlife films are a valid and distinct film and…

  10. The Harvard Project Physics Film Program

    Science.gov (United States)

    Bork, Alfred M.

    1970-01-01

    States the philosophy behind the Harvard Project Physics (HPP) film program. Describes the three long HPP films. Lists the 48 color film loops covering six broad topics, primarily motion and energy. The 8-mm silent loops are synchronized with the text materials. Explains some of the pedagogical possibilities of these film loops. (RR)

  11. A Long Look at the Short Film

    Science.gov (United States)

    Miller, Franklin, Jr.

    1971-01-01

    The history of the short film and the single concept film loop is presented. Lists fourteen reasons why it may be necessary to make and use a film loop. Film loop projectors are analyzed according to present features and deficiencies with predictions on future improvements. (DS)

  12. Geoflicks Reviewed--Films about Hawaiian Volcanoes.

    Science.gov (United States)

    Bykerk-Kauffman, Ann

    1994-01-01

    Reviews 11 films on volcanic eruptions in the United States. Films are given a one- to five-star rating and the film's year, length, source and price are listed. Top films include "Inside Hawaiian Volcanoes" and "Kilauea: Close up of an Active Volcano." (AIM)

  13. "Space slitter" for film or tape

    Science.gov (United States)

    Johnson, W. H.

    1978-01-01

    Device cuts film or tape into strips by guiding film in channel under cutting blades. Device is operated by lifting pressure bar to insert blades into film. Film is then pulled through blades. Cutter has potential uses in advertising, commercial art, and publishing fields.

  14. American Film Genres: Approaches to a Critical Theory of Popular Film.

    Science.gov (United States)

    Kaminsky, Stuart M.

    This book is divided into twelve sections and contains photographs from many of the films discussed. The introduction defines film genre and describes the general theories behind this book; "The Individual Film" analyzes the film "Little Caesar" as it relates to the genre of gangster films; "Comparative Forms"…

  15. Student film clinches top prize in film competition

    OpenAIRE

    Elliott, Jean

    2006-01-01

    Virginia Tech senior Tim Leaton earned the top prize in the widely acclaimed Film Your Issue (FYI) competition - an eight-week paid internship at Disney Studios in Los Angeles. Leaton's one-minute film, "Orphans in Africa," won the nationwide contest, an initiative to encourage young Americans, age 18 to 26, to engage in social issues and add their voices to the public dialogue.

  16. Scoring an Abstract Contemporary Silent Film

    OpenAIRE

    Frost, Crystal

    2014-01-01

    I composed an original digital audio film score with full sound design for a contemporary silent film called Apple Tree. The film is highly conceptual and interpretive and required a very involved, intricate score to successfully tell the story. In the process of scoring this film, I learned new ways to convey an array of contrasting emotions through music and sound. After analyzing the film's emotional journey, I determined that six defining emotions were the foundation on which to build an ...

  17. Cellulose triacetate, thin film dielectric capacitor

    Science.gov (United States)

    Yen, Shiao-Ping S. (Inventor); Jow, T. Richard (Inventor)

    1995-01-01

    Very thin films of cellulose triacetate are cast from a solution containing a small amount of high boiling temperature, non-solvent which evaporates last and lifts the film from the casting surface. Stretched, oriented, crystallized films have high electrical breakdown properties. Metallized films less than about 2 microns in thickness form self-healing electrodes for high energy density, pulsed power capacitors. Thicker films can be utilized as a dielectric for a capacitor.

  18. Testing Bonds Between Brittle And Ductile Films

    Science.gov (United States)

    Wheeler, Donald R.; Ohsaki, Hiroyuki

    1989-01-01

    Simple uniaxial strain test devised to measure intrinsic shear strength. Brittle film deposited on ductile stubstrate film, and combination stretched until brittle film cracks, then separates from substrate. Dimensions of cracked segments related in known way to tensile strength of brittle film and shear strength of bond between two films. Despite approximations and limitations of technique, tests show it yields semiquantitative measures of bond strengths, independent of mechanical properties of substrates, with results reproducible with plus or minus 6 percent.

  19. Music as word: Film music - superlibretto?

    OpenAIRE

    Ćirić Marija

    2013-01-01

    The aim of his paper is to prove that film music can be understood as authentic narrative force: film music as word / discourse and its superlibretto status. Superlibretto is the status of music in a film which is constructing its own (aural) reality and is narrating, speaking its own text which creates a wholesome film meaning. The existence of superlibretto is substantiated by fundamental theoretic concepts of film music and practically proven by analyses...

  20. Silencing cinema: film censorship around the world

    OpenAIRE

    Biltereyst, Daniël; Vande Winkel, Roel

    2013-01-01

    Why does oppression by censorship affect the film industry far more frequently than any other mass media? "Silencing Cinema" brings together the key issues and authors to examine instances of film censorship throughout the world. Including essays by some of today's leading film historians, the book offers groundbreaking historical research on film censorship in major film production countries, including the United States, the United Kingdom, Russia/Soviet Union, India, China, and Nigeria, amo...

  1. Viscosity of particle laden films

    Science.gov (United States)

    Timounay, Yousra; Rouyer, Florence

    2017-06-01

    We perform retraction experiments on soap films where large particles bridge the two interfaces. Local velocities are measured by PIV during the unstationnary regime. The velocity variation in time and space can be described by a continuous fluid model from which effective viscosity (shear and dilatational) of particulate films is measured. The 2D effective viscosity of particulate films η2D increases with particle surface fraction ϕ: at low ϕ, it tends to the interfacial dilatational viscosity of the liquid/air interfaces and it diverges at the critical particle surface fraction ϕc ≃ 0.84. Experimental data agree with classical viscosity laws of hard spheres suspensions adapted to the 2D geometry, assuming viscous dissipation resulting from the squeeze of the liquid/air interfaces between the particles. Finally, we show that the observed viscous dissipation in particulate films has to be considered to describe the edge velocity during a retraction experiment at large particle coverage.

  2. PTFE films with improved flexibility

    Science.gov (United States)

    Muraca, R. F.; Koch, A. A.

    1972-01-01

    Development and application of flexible polytetrafluroethylene films for expulsion bladders in spacecraft propellant tanks are described. Flexibility of material is obtained by reducing crystallinity through annealing and quenching in water. Physical and mechanical properties of material are presented.

  3. Silver Films with Hierarchical Chirality.

    Science.gov (United States)

    Ma, Liguo; Cao, Yuanyuan; Duan, Yingying; Han, Lu; Che, Shunai

    2017-07-17

    Physical fabrication of chiral metallic films usually results in singular or large-sized chirality, restricting the optical asymmetric responses to long electromagnetic wavelengths. The chiral molecule-induced formation of silver films prepared chemically on a copper substrate through a redox reaction is presented. Three levels of chirality were identified: primary twisted nanoflakes with atomic crystal lattices, secondary helical stacking of these nanoflakes to form nanoplates, and tertiary micrometer-sized circinates consisting of chiral arranged nanoplates. The chiral Ag films exhibited multiple plasmonic absorption- and scattering-based optical activities at UV/Vis wavelengths based on their hierarchical chirality. The Ag films showed chiral selectivity for amino acids in catalytic electrochemical reactions, which originated from their primary atomic crystal lattices. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Laser deposition of HTSC films

    International Nuclear Information System (INIS)

    Sobol', Eh.N.; Bagratashvili, V.N.; Zherikhin, A.N.; Sviridov, A.P.

    1990-01-01

    Studies of the high-temperature superconducting (HTSC) films fabrication by the laser deposition are reviewed. Physical and chemical processes taking place during laser deposition are considered, such as the target evaporation, the material transport from the target to the substrate, the film growth on the substrate, thermochemical reactions and mass transfer within the HTSC films and their stability. The experimental results on the laser deposition of different HTSC ceramics and their properties investigations are given. The major technological issues are discussed including the deposition schemes, the oxygen supply, the target compositions and structure, the substrates and interface layers selection, the deposition regimes and their impact on the HTSC films properties. 169 refs.; 6 figs.; 2 tabs

  5. Engineering Graphene Films from Coal

    Science.gov (United States)

    Vijapur, Santosh H.

    Graphene is a unique material with remarkable properties suitable for a wide array of applications. Chemical vapor deposition (CVD) is a simple technique for synthesis of large area and high quality graphene films on various metal substrates. Among the metal substrates, copper has been shown to be an excellent support for the growth of graphene films. Traditionally, hydrocarbon gases are used for the graphene synthesis via CVD. Unconventional solid carbon sources such as various polymers and food waste have also shown great potential for synthesis of graphene films. Coal is one such carbon enriched and abundantly available unconventional source. Utilization of coal as a carbon source to synthesize large area, transparent, and high quality few-layer graphene films via CVD has been demonstrated in the present work. Hydrocarbon gases are released as products of coal pyrolysis at temperatures ≥400 °C. This study hypothesized that, these hydrocarbon gases act as precursors for the synthesis of graphene films on the copper substrate. Hence, atmospheric pressure CVD and low temperature of 400 °C were utilized initially for the production of graphene films. These conditions were suitable for the formation of amorphous carbon (a-C) films but not crystalline graphene films that were the objective of this work. The synthesized a-C films on the copper substrate were shown to be uniform and transparent with large surface area. The thickness and surface roughness of the a-C films were determined to have typical values of 5 nm and 0.55 nm, respectively. The a-C film has >95 % optical transmittance and sheet resistivity of 0.6 MO sq-1. These values are comparable to other carbon thin films synthesized at higher temperatures. Further, the a-C films were transferred onto any type of substrate such as silicon wafer and titanium foil, and can be utilized for diverse applications. However, crystalline graphene films were not produced by implementing atmospheric pressure CVD and low

  6. Aasta Suurim Film? / Chili Palmer

    Index Scriptorium Estoniae

    Palmer, Chili

    2002-01-01

    Peter Jacksoni esimene film J.R.R. Tolkieni triloogia "Sõrmuste isand" alusel - "Sõrmuse vennaskond", ("The Lord of the Rings : The Fellowship of the Ring") : Uus-Meremaa, Ameerika Ühendriigid 2001

  7. Mechanical integrity of thin films

    International Nuclear Information System (INIS)

    Hoffman, R.W.

    1979-01-01

    Mechanical considerations starting with the initial film deposition including questions of adhesion and grading the interface are reviewed. Growth stresses, limiting thickness, stress relief, control aging, and creep are described

  8. Nature tourism and Irish film

    OpenAIRE

    Brereton, Pat

    2006-01-01

    This article provides a historical overview and reading of seminal Irish film from the perspective of nature tourism. Within Irish cultural studies, tourism is frequently equated with an overly romantic image of the island, which has been used to sell the country abroad. However, using notions like the tourist gaze and taking on board influential debates around space/place, one can posit a more progressive environmental vision of nature and landscape in our readings of film.

  9. Film holder for radiographing tubing

    International Nuclear Information System (INIS)

    Davis, E.V.; Foster, B.E.

    1976-01-01

    A film cassette is described which may be easily placed about tubing or piping and readily held in place while radiographic inspection is performed. A pair of precurved light-impervious semi-rigid plastic sheets, hinged at one edge, enclose sheet film together with any metallic foils or screens. Other edges are made light-tight with removable caps, and the entire unit is held securely about the object to be radiographed with a releasable fastener such as a strip of Velcro

  10. Film holder for radiographing tubing

    Science.gov (United States)

    Davis, Earl V.; Foster, Billy E.

    1976-01-01

    A film cassette is provided which may be easily placed about tubing or piping and readily held in place while radiographic inspection is performed. A pair of precurved light-impervious semi-rigid plastic sheets, hinged at one edge, enclose sheet film together with any metallic foils or screens. Other edges are made light-tight with removable caps, and the entire unit is held securely about the object to be radiographed with a releasable fastener such as a strip of Velcro.

  11. Microwave properties of HTS films

    International Nuclear Information System (INIS)

    Cooke, D.W.; Arendt, P.M.; Grey, E.R.; Muenchausen, R.E.; Bennett, B.L.; Foltyn, S.R.; Estler, R.C.; Wu, X.D.; Reeves, G.A.; Elliott, N.E.; Brown, D.R.; Portis, A.M.; Taber, R.C.; Mogrocampero, A.

    1990-01-01

    High-frequency applications of high- temperature superconductors generally fall into two categories: 1) devices that require low values (relative to Cu) of surface resistance R S in ambient surface magnetic fields H rf ; and 2) devices that require low R S in modest fields (H rf ∼ 250 Oe). Moreover, many applications can be realized with small- surface-area films (∼ 1 cm 2 ) whereas others require larger areas - radiofrequency (rf) cavities, for example. Regardless of the application, the potential of HTS films is predicted on satisfying one or both of the above-stated requirements. The authors have measured the surface resistance of small-area (1 cm 2 ) and large-area (6.5 cm 2 ) YBa 2 Cu 3 O 7 (YBCO) films that have been laser ablated onto LaA ell O 3 substrates, large-area (5.1 cm 2 YBCO films that have been e-beam deposited onto LaA ell O 3 , and large-area (11.4 cm 2 ) T ell-based films that have been magnetron sputtered onto metallic substrates. The best R S values are obtained from the 1-cm 2 laser-ablated films; they are 40 μΩ and 340 μΩ at 4 K And 77 K, respectively (ω/2π = 10 GHz). Comparable values for Cu are 6 and 13 mΩ, respectively. Large-area T ell-based films yield typical R S values of 4 mΩ and 14 mΩ at 4 K and 77 K, respectively (ω/2π = 18 GHz). The dependence of R S on H rf for these films indicates that surface fields as large as 55 Oe can be achieved with R S increasing only by a factor of 10. This field dependence is associated with c-axis texturing

  12. Science and film-making.

    Science.gov (United States)

    Gouyon, Jean-Baptiste

    2016-01-01

    The essay reviews the literature, mostly historical, on the relationship between science and film-making, with a focus on the science documentary. It then discusses the circumstances of the emergence of the wildlife making-of documentary genre. The thesis examined here is that since the early days of cinema, film-making has evolved from being subordinate to science, to being an equal partner in the production of knowledge, controlled by non-scientists. © The Author(s) 2015.

  13. Censoring and Selling Film Noir

    Directory of Open Access Journals (Sweden)

    Sheri Chinen Biesen

    2015-05-01

    Full Text Available Film noir is known for its duplicity. Industry censors considered 1940s noir cinema provocative, salacious and ‘sordid.’ Hollywood studios walked a fine line between appearing to comply with Hays office Production Code censorship while simultaneously pushing the envelope of its moral constraints, then hyping and sensationalizing censorable sex, violence and hard-hitting themes to sell noir films to the public. In fact, studios capitalized on the racy explicit nature of noir pictures in publicity contradicting assurances of censorial compliance. For instance, censor Joseph Breen was “shocked” when MGM purchased James Cain’s The Postman Always Rings Twice. It was banned for a decade. Yet, ten years later as filmmakers adapted hardboiled fiction, Breen assured religious groups it would “not be offensive.” Yet, it was promoted as “torrid,” “too hot to handle” with Lana Turner in a bathing suit finding “Love at Laguna Beach” with hunky John Garfield who clamored, “You must be a she-devil,” suggesting far more sex, skin and “savage boldness” than is shown in the film. Film noir responded to Production Code censorship and other regulatory factors, including Office of War Information Bureau of Motion Pictures restrictions on Hollywood screen depictions of the domestic American home front (or overseas combat front, and Office of Censorship strictures such as a wartime ban on screen gangsters as ‘un-American’ for propaganda purposes in World War II-era noir films centering on criminals. These multiple censorship entities often collided. This regulatory climate catalyzed the development of film noir, a dark cycle of shadowy 1940s-50s crime films that boomed by World War II and evolved over the postwar era. I will investigate extensive primary archival research—including scripts, memos from industry censors, writers, directors, producers, and publicity records—to compare how film noir was censored and sold.

  14. The Art of Teaching Social Studies with Film

    Science.gov (United States)

    Russell, William B., III

    2012-01-01

    Teaching with film is a powerful and meaningful instructional strategy. This article discusses five classroom-tested methods for teaching with film: (1) film as a visual textbook, (2) film as a depicter of atmosphere, (3) film as an analogy, (4) film as a historiography, and (5) film as a springboard. Each of the methods discussed includes…

  15. The Reincarnation of Animated Film

    Directory of Open Access Journals (Sweden)

    Šošková Eva

    2017-12-01

    Full Text Available Throughout its entire history, Slovak animated film has had the form of figurative narrative art or craft. For this reason, the author of this study examines its post-1989 development through the prism of the body. Since the most visible change that has affected contemporary film aesthetics is the feminization of animated film in terms of authorship, the study primarily focuses on the ability of an animated body to represent gender and gender roles. It attempts to capture the most significant changes in the depiction of the body in authorial animated film before and after 1989, in more detail record the post-revolution changes in the body, and relate this to the changes in the institutional background of animated film. Animated bodies have developed from “ordinary people” from a dominant male point of view in socio-critical socialist production through female characters in interaction with clearly distinguished male characters in the films of female authors from the Academy of Performing Arts, the crisis of stereotypical masculinity in the production of male authors to independent women looking for their own identity inside themselves, without relating themselves to their male counterparts.

  16. Photoconductivity of thin organic films

    International Nuclear Information System (INIS)

    Tkachenko, Nikolai V.; Chukharev, Vladimir; Kaplas, Petra; Tolkki, Antti; Efimov, Alexander; Haring, Kimmo; Viheriaelae, Jukka; Niemi, Tapio; Lemmetyinen, Helge

    2010-01-01

    Thin organic films were deposited on silicon oxide surfaces with golden interdigitated electrodes (interelectrode gap was 2 μm), and the film resistivities were measured in dark and under white light illumination. The compounds selected for the measurements include molecules widely used in solar cell applications, such as polythiophene (PHT), fullerene (C 60 ), pyrelene tetracarboxylic diimide (PTCDI) and copper phthalocyanine (CuPc), as well as molecules potentially interesting for photovoltaic applications, e.g. porphyrin-fullerene dyads. The films were deposited using thermal evaporation (e.g. for C 60 and CuPc films), spin coating for PHT, and Langmuir-Schaeffer for the layer-by-layer deposition of porphyrin-fullerene dyads. The most conducting materials in the series are films of PHT and CuPc with resistivities 1.2 x 10 3 Ω m and 3 x 10 4 Ω m, respectively. Under light illumination resistivity of all films decreases, with the strongest light effect observed for PTCDI, for which resistivity decreases by 100 times, from 3.2 x 10 8 Ω m in dark to 3.1 x 10 6 Ω m under the light.

  17. Two days of films

    CERN Document Server

    2011-01-01

    The Chinese community at CERN and the CERN CineClub, on the occasion of the Chinese New Year, invite everyone to two days of films Thursday 3 February 2011 at 20:30 - CERN Council Chamber Eat drink man woman Directed by Ang LEE (Taiwan, 1994) 122 min. With Sihung Lung, Yu-Wen Wang, Chien-Lien Wu, Kuei-Mei Yang Senior Master Chef Chu lives in a large house in Taipei with his three unmarried daughters, Jia-Jen, a chemistry teacher converted to Christianity, Jia-Chien, an airline executive, and Jia-Ning, a student who also works in a fast food restaurant. Life in the house revolves around the ritual of an elaborate dinner each Sunday, and the love lives of all the family members. Original version Mandarin with English subtitles Friday 4 February 2011 at 19:30 - CERN Council Chamber Adieu, ma concubine Directed by Chen KAIGE (China / Hong Kong, 1993) 171 min. With Leslie Cheung, Fengyi Zhang, Li Gong "Farewell, My Concubine" is a movie with two parallel, intertwined stories. It is the story of two performers in t...

  18. As Film Goes Byte: The Change From Analog to Digital Film Perception

    OpenAIRE

    Loertscher, Miriam Laura; Weibel, David; Spiegel, Simon; Flueckiger, Barbara; Mennel, Pierre; Mast, Fred; Iseli, Christian

    2016-01-01

    The digital revolution changed film production in many ways. Until the end of the 20th century, most film professionals and critics preferred celluloid film. However, no previous empirical study compared complete narrative films recorded with analog and digital cinematography. Three short narrative films were produced with an analog and a digital camera attached to a 3D rig in order to control all optical parameters. In postproduction, a third version of a digital film was created to mimic th...

  19. As Film Goes Byte: The Change From Analog to Digital Film Perception.

    OpenAIRE

    Loertscher M. L. Weibel D. Spiegel S. Flueckiger B. Mennel P. Mast F. W. & Iseli C.

    2016-01-01

    The digital revolution changed film production in many ways. Until the end of the 20th century most film professionals and critics preferred celluloid film. However no previous empirical study compared complete narrative films recorded with analog and digital cinematography. Three short narrative films were produced with an analog and a digital camera attached to a 3D rig in order to control all optical parameters. In postproduction a third version of a digital film was created to mimic the a...

  20. New radiochroic film densitometry system

    International Nuclear Information System (INIS)

    Tran, T.; Freeman, N.; Johnston, P.

    2004-01-01

    Full text: The advantages of radiochromic film in radiation dosimetry are well known. They include dosimetry with high spatial resolution, response less dependent on incident beam energy than common radiotherapy films (such as the Kodak XV films), tissue equivalence and the ability to be handled and developed in room light. This study entails the design and testing of a new radiochromic densitometry system. The system consists of a single light emitting diode (LED), opaque 'diffuser' and digital camera. Customised software was developed to analyse images obtained from the digital camera. Standard characteristics of a commercially available super bright red LED (peak wavelength 625nm) was analysed in order to determine the voltage, current and intensity settings. Various methods in diffusing the single LED light source were investigated and it was determined that an opaque transmission 'diffuser' was the best alternative. While the intensity of the LED was kept constant, the digital camera exposure times were varied in order to determine a setting which would produce the best image exposure. The system was designed and built and preliminary tests were carried using the standard radiochromic film GafChromic MD-55-2. LED current vs. voltage curves were characteristically exponential for positive voltage. Studies into LED intensity versus camera exposure produced an unexpected result. At high exposures the camera saturates and if even higher exposures are used the LED intensity apparently decreases. This was thought to be due to the pixels in the charge couple device (CCD) saturating and eventually electronically 'bleeding' into adjacent pixels. Using the opaque transmission 'diffuser' enabled successful use of the single LED light producing an area of homogenous light intensity in which images of radiochromic films can be obtained. Preliminary results from radiochromic film characteristic studies show no unusual results. The single LED, diffuser and digital camera

  1. Music as word: Film music - superlibretto?

    Directory of Open Access Journals (Sweden)

    Ćirić Marija

    2013-01-01

    Full Text Available The aim of his paper is to prove that film music can be understood as authentic narrative force: film music as word / discourse and its superlibretto status. Superlibretto is the status of music in a film which is constructing its own (aural reality and is narrating, speaking its own text which creates a wholesome film meaning. The existence of superlibretto is substantiated by fundamental theoretic concepts of film music and practically proven by analyses of examples taken from the opus of Serbian film composer Zoran Simjanović.

  2. Family Porn - the zodiac-film

    DEFF Research Database (Denmark)

    Thorsen, Christian Isak

    2015-01-01

    This article addresses the highly popular Danish Zodiac films, a series of six films made between 1973 and 1978. What was extraordinary about the films was their combination of traditional popular comedy and hard-core porn. Analysing the films� combination of comedy and pornography from a histori......This article addresses the highly popular Danish Zodiac films, a series of six films made between 1973 and 1978. What was extraordinary about the films was their combination of traditional popular comedy and hard-core porn. Analysing the films� combination of comedy and pornography from...

  3. Passivation Effects in Copper Thin Films

    International Nuclear Information System (INIS)

    Wiederhirn, G.; Nucci, J.; Richter, G.; Arzt, E.; Balk, T. J.; Dehm, G.

    2006-01-01

    We studied the influence of a 10 nm AlxOy passivation on the stress-temperature behavior of 100 nm and 1 μm thick Cu films. At low temperatures, the passivation induces a large tensile stress increase in the 100 nm film; however, its effect on the 1 μm film is negligible. At high temperatures, the opposite behavior is observed; while the passivation does not change the 100 nm film behavior, it strengthens the 1 μm film by driving it deeper into compression. These observations are explained in light of a combination of constrained diffusional creep and dislocation dynamics unique to ultra-thin films

  4. Use of a horror film in psychotherapy.

    Science.gov (United States)

    Turley, J M; Derdeyn, A P

    1990-11-01

    Modern improvements in the technology of cinematic special effects have ushered in a new genre of vivid and graphic horror film. The numerous sequels of these films attest to their popularity among adolescents and young adults. Considerable concern has arisen on the part of parents, professionals, and policymakers regarding adverse effects of these films upon children. The authors discuss the meaning of a horror film to a troubled 13-year-old boy and describe the use of the film in his psychotherapy. The modern horror film serves many of the same functions for the adolescent that the traditional fairy tale serves for the younger child.

  5. Superhydrophobic films and methods for making superhydrophobic films

    Science.gov (United States)

    Aytug, Tolga; Paranthaman, Mariappan Parans; Simpson, John T.; Bogorin, Daniela Florentina

    2017-09-26

    This disclosure relates to methods that include depositing a first component and a second component to form a film including a plurality of nanostructures, and coating the nanostructures with a hydrophobic layer to render the film superhydrophobic. The first component and the second component can be immiscible and phase-separated during the depositing step. The first component and the second component can be independently selected from the group consisting of a metal oxide, a metal nitride, a metal oxynitride, a metal, and combinations thereof. The films can have a thickness greater than or equal to 5 nm; an average surface roughness (Ra) of from 90 to 120 nm, as measured on a 5 .mu.m.times.5 .mu.m area; a surface area of at least 20 m.sup.2/g; a contact angle with a drop of water of at least 120 degrees; and can maintain the contact angle when exposed to harsh conditions.

  6. Films from the Couch: Film Theory and Psychoanalysis

    Directory of Open Access Journals (Sweden)

    Pedro Sangro Colón

    2008-10-01

    Full Text Available   Different disciplines have contributed to weaving a theory of psychoanalysis in the cinema: ranging from the loans from anthropology and experimental psychology, to proposals belonging to the specific sphere of film theory, such as Filmology, Text Analysis or Feminist Theory in films. In all cases, the aim is to establish a relationship between the significance structure that governs the cinema and psychology, so as to confirm that the cinema’s system of representation is modelled on our unconscious psychological apparatus, as was explained by the psychoanalyst Jacques Lacan, among others. The arrival of psychoanalysis in film thought forges the idea that considers the cinema as an auxiliary psychological device capable of making us subjects and submerging us in the emotions in play in the conflicts proposed by any audiovisual story.

  7. Field noise near ferromagnetic films

    Science.gov (United States)

    McMichael, Robert; Liu, Hau-Jian; Yoon, Seungha

    Thermally driven magnetization fluctuations can be viewed as a nuisance noise source or as interesting physics. For example, mag noise in a field sensor may set the minimum detectable field of that sensor. On the other hand, the field noise spectrum reflects the dynamics of the magnetic components, which are essential for device operation. Here, we model the field noise spectrum near the surface of a magnetic film due to thermal spin waves, and we calculate its effect on the T1 relaxation rate of a nearby nitrogen-vacancy (NV) center spin. The model incorporates four components: the spin wave dispersion of the magnetization in a finite-thickness film, thermal excitation of spin waves, the coupling geometry between waves in the film and an external point dipole and finally, the relaxation dynamics of the NV spin. At a distance of 100 nm above a 50 nm thick permalloy film, we find that the strongest stray fields are along the film normal and parallel to the magnetization, on the order of 1 mA m-1 Hz- 1 / 2 or 1 nT Hz- 1 / 2, yielding relaxation times on the order of 10 μs. The spin wave field noise can dominate the intrinsic relaxation, (T1 1 ms) of the NV center spin.

  8. Receptor saturation in roentgen films

    Energy Technology Data Exchange (ETDEWEB)

    Strid, K G; Reichmann, S [Sahlgrenska Sjukhuset, Goeteborg (Sweden)

    1980-01-01

    Roentgen-film recording of small object details of low attenuation differences (e.g. pulmonary vessels) is regularly seen to be impaired when the film is exposed to yield high values of optical density (D). This high-density failure is due to receptor saturation, which implies that at high exposure values most silver halide grains of the film are made developable, leaving few grains available to receive additional informative photons. The receptor saturation is analysed by means of a mathematical model of a non-screen film yielding Dsub(max) = 2.0. Optimum recording, defined by maximum signal-to-noise ratio in the image, is found at D approximately 0.64, corresponding to, on an average, 1.6 photons absorbed per grain. On the other hand, maximum contrast occurs at D approximately 1.4, where, on the average, 3.6 photons are absorbed per grain. The detective quantum efficiency of the film, i.e. the fraction of the photons actually contributing to the information content of the image, drops from 41 per cent at maximum signal-to-noise ratio to a mere 10 per cent at maximum contrast.

  9. Film Learning in the Classroom

    Science.gov (United States)

    Kopp, R.; Liddicoat, J.

    2012-04-01

    Is a picture worth a thousand words? That is a bit of a trick question. We process films and photographs very differently from the way we wrestle with words. They literally work on a different part of our brain, and their testimony is typically weighed differently as well, both in terms of emotional and evidentiary value. Film rhetoric does not quite play with the same deck of cards as classical rhetoric: it shuffles in some jokers and wild cards. To effectively use film in the classroom, faculty need to understand that these visual texts resemble but at the same time differ from written texts. By training faculty in various disciplines in the social and natural sciences to become more aware of not just what a film they are showing in a course says, but how it says it, the faculty can help frame their discussions in a dramatic new way, underlining the crucial connections between content and form that are essential to all critical thinking. There is a real urgency to this task in a world where more and more of the information that students receive is transmitted through visual means from sources of varying degrees of integrity and objectivity. Although this is a life skill that needs to be developed at any age, it most definitely is required at the university level. Recognizing this need, we will share our experience using film in a constructive way for teaching students social and natural sciences at colleges and universities in New York City.

  10. Spray pyrolysis process for preparing superconductive films

    International Nuclear Information System (INIS)

    Hsu, H.M.; Yee, I.Y.

    1991-01-01

    This paper describes a spray pyrolysis method for preparing thin superconductive film. It comprises: preparing a spray pyrolysis solution comprising Bi,Sr,Ca and Cu metals in a solvent; heating a substrate to a first temperature; spraying the solution onto the heated substrate to form a film thereon; heating the film and substrate to a second temperature of about 700 degrees-825 degrees C, the second temperature being higher than the first temperature; heating the film and substrate to a third temperature of about 870 degrees-890 degrees C to melt the film; once the film and substrate reach the third temperature, further heat treating the film and substrate; cooling the film and substrate to ambient temperature. This patent also describes a spray pyrolysis method for preparing thin superconductive films. It comprises: preparing a spray pyrolysis solution comprising Bi, Ca and Cu metals and fluxing agent in a solvent; heating a substrate to a first temperature; spraying the solution onto the heated substrate to form a film thereon; heating the film and substrate to a second temperature about 700 degrees-825 degrees C, the second temperature being higher than the first temperature; heating the film and substrate at a third temperature about 840 degrees-860 degrees C; and cooling the film and substrate to ambient temperature

  11. Thermogravimetric analysis of fuel film evaporation

    Institute of Scientific and Technical Information of China (English)

    HU Zongjie; LI Liguang; YU Shui

    2006-01-01

    Thermogravimetric analysis (TGA) was compared with the petrochemical distillation measurement method to better understand the characteristics of fuel film evaporation at different wall tem- peratures. The film evaporation characteristics of 90# gasoline, 93# gasoline and 0# diesel with different initial thicknesses were investigated at different environmental fluxes and heating rates. The influences of heating rate, film thickness and environmental flux on fuel film evaporation for these fuels were found. The results showed that the environmental conditions in TGA were similar to those for fuel films in the internal combustion engines, so data from TGA were suitable for the analysis of fuel film evaporation. TGA could simulate the key influencing factors for fuel film evaporation and could investigate the basic quantificational effect of heating rate and film thickness. To get a rapid and sufficient fuel film evaporation, sufficiently high wall temperature is necessary. Evaporation time decreases at a high heating rate and thin film thickness, and intense gas flow is important to promoting fuel film evaporation. Data from TGA at a heating rate of 100℃/min are fit to analyze the diesel film evaporation during cold-start and warming-up. Due to the tense molecular interactions, the evaporation sequence could not be strictly divided according to the boiling points of each component for multicomponent dissolved mixture during the quick evaporation process, and the heavier components could vaporize before reaching their boiling points. The 0# diesel film would fully evaporate when the wall temperature is beyond 250℃.

  12. Cracking in Drying Colloidal Films

    Science.gov (United States)

    Singh, Karnail B.; Tirumkudulu, Mahesh S.

    2007-05-01

    It has long been known that thick films of colloidal dispersions such as wet clays, paints, and coatings crack under drying. Although capillary stresses generated during drying have been recently identified as the cause for cracking, the existence of a maximum crack-free film thickness that depends on particle size, rigidity, and packing has not been understood. Here, we identify two distinct regimes for crack-free films based on the magnitude of compressive strain at the maximum attainable capillary pressure and show remarkable agreement of measurements with our theory. We anticipate our results to not only form the basis for design of coating formulations for the paints, coatings, and ceramics industry but also assist in the production of crack-free photonic band gap crystals.

  13. Solar advanced internal film receiver

    International Nuclear Information System (INIS)

    Torre Cabezas, M. de la

    1990-01-01

    In a Solar Central Internal Film Receiver, the heat absorbing fluid (a molten nitrate salt) flows in a thin film down over the non illuminated side of an absorber panel. Since the molten salt working fluid is not contained in complicated tube manifolds, the receiver design is simples than a conventional tube type-receiver resulting in a lower cost and a more reliable receiver. The Internal Film Receiver can be considered as an alternative to the Direct Absorption Receiver, in the event that the current problems of the last one can not be solved. It also describes here the test facility which will be used for its solar test, and the test plans foreseen. (Author) 17 refs

  14. Co-sputtered optical films

    Energy Technology Data Exchange (ETDEWEB)

    Misiano, C; Simonetti, E [Selenia S.p.A., Rome (Italy)

    1977-06-01

    The co-sputtering of two dielectric materials with indices of refraction as widely different as possible has been investigated with the aim of obtaining both homogeneous films with an intermediate index of refraction and inhomogeneous films with predetermined profiles. An rf sputtering module is described which has been especially designed, with two separate cathodes and two independent tunable rf generators. The substrates are placed on a circular anode rotating underneath the two cathodes. So far mainly CeO/sub 2/, TiO2 and SiO/sub 2/ targets have been used. The deposition rate from each cathode and the total film thickness are determined by means of two quartz thickness monitors, sputtering compatible. Values obtained for the refractive index and optical thickness are reported, as well as repeatability, mechanical and chemical characteristics, reliability and high power optical radiation resistance. Finally, results obtained on optical components of practical interest are discussed.

  15. Duplex Tear Film Evaporation Analysis.

    Science.gov (United States)

    Stapf, M R; Braun, R J; King-Smith, P E

    2017-12-01

    Tear film thinning, hyperosmolarity, and breakup can cause irritation and damage to the human eye, and these form an area of active investigation for dry eye syndrome research. Recent research demonstrates that deficiencies in the lipid layer may cause locally increased evaporation, inducing conditions for breakup. In this paper, we explore the conditions for tear film breakup by considering a model for tear film dynamics with two mobile fluid layers, the aqueous and lipid layers. In addition, we include the effects of osmosis, evaporation as modified by the lipid, and the polar portion of the lipid layer. We solve the system numerically for reasonable parameter values and initial conditions and analyze how shifts in these cause changes to the system's dynamics.

  16. Single-layer nano-carbon film, diamond film, and diamond/nano-carbon composite film field emission performance comparison

    International Nuclear Information System (INIS)

    Wang, Xiaoping; Wang, Jinye; Wang, Lijun

    2016-01-01

    A series of single-layer nano-carbon (SNC) films, diamond films, and diamond/nano-carbon (D/NC) composite films have been prepared on the highly doped silicon substrate by using microwave plasma chemical vapor deposition techniques. The films were characterised by scanning electron microscopy, Raman spectroscopy, and field emission I-V measurements. The experimental results indicated that the field emission maximum current density of D/NC composite films is 11.8–17.8 times that of diamond films. And the field emission current density of D/NC composite films is 2.9–5 times that of SNC films at an electric field of 3.0 V/μm. At the same time, the D/NC composite film exhibits the advantage of improved reproducibility and long term stability (both of the nano-carbon film within the D/NC composite cathode and the SNC cathode were prepared under the same experimental conditions). And for the D/NC composite sample, a high current density of 10 mA/cm"2 at an electric field of 3.0 V/μm was obtained. Diamond layer can effectively improve the field emission characteristics of nano-carbon film. The reason may be due to the diamond film acts as the electron acceleration layer.

  17. US/Russian Joint Film Test

    Science.gov (United States)

    Slater, Richard

    1996-01-01

    A joint U.S./Russian film test was conducted during MIR Mission 18 to evaluate the effects of radiation on photographic film during long-duration space flights. Two duplicate sets of film were flown on this MIR mission: one set was processed and evaluated by the NASA/JSC Photographic Laboratory, and the other by the RKK Energia's Photographic Laboratory in Moscow. This preliminary report includes only the results of the JSC evaluation (excluding the SN-10 film which was not available for evaluation at the time this report was written). The final report will include an evaluation by JSC of the SN-10 film and an evaluation of the test data by the RKK Energia. ISC's evaluation of the test data showed the positive film flown was damaged very little when exposed to approximately 8 rads of radiation. Two of the three negative films were significantly damaged and the third film was damaged only moderately.

  18. Anmeldelse af Evolution, Literature and Film

    DEFF Research Database (Denmark)

    Grodal, Torben Kragh

    2011-01-01

    Diskussion af basisproblemer i evolutionær fiktionsteori med udgangspunkt i en anmeldelse af Evolution, Literature and Film......Diskussion af basisproblemer i evolutionær fiktionsteori med udgangspunkt i en anmeldelse af Evolution, Literature and Film...

  19. Oromucosal film preparations: classification and characterization methods.

    Science.gov (United States)

    Preis, Maren; Woertz, Christina; Kleinebudde, Peter; Breitkreutz, Jörg

    2013-09-01

    Recently, the regulatory authorities have enlarged the variety of 'oromucosal preparations' by buccal films and orodispersible films. Various film preparations have entered the market and pharmacopoeias. Due to the novelty of the official monographs, no standardized characterization methods and quality specifications are included. This review reports the methods of choice to characterize oromucosal film preparations with respect to biorelevant characterization and quality control. Commonly used dissolution tests for other dosage forms are not transferable for films in all cases. Alternatives and guidance on decision, which methods are favorable for film preparations are discussed. Furthermore, issues about requirements for film dosage forms are reflected. Oromucosal film preparations offer a wide spectrum of opportunities. There are a lot of suggestions in the literature on how to control the quality of these innovative products, but no standardized tests are available. Regulatory authorities need to define the standards and quality requirements more precisely.

  20. Semiconductor-nanocrystal/conjugated polymer thin films

    Science.gov (United States)

    Alivisatos, A. Paul; Dittmer, Janke J.; Huynh, Wendy U.; Milliron, Delia

    2014-06-17

    The invention described herein provides for thin films and methods of making comprising inorganic semiconductor-nanocrystals dispersed in semiconducting-polymers in high loading amounts. The invention also describes photovoltaic devices incorporating the thin films.

  1. Soap Films as 1D waveguides

    Directory of Open Access Journals (Sweden)

    Emile Olivier

    2014-01-01

    Full Text Available Laser light is injected in a free standing horizontal draining soap film through the glass frame sustaining the film. Two propagation regimes are clearly identified depending on the film thickness. At the beginning of the drainage, the soap film behaves as a multimode-one dimensional optofiuidic waveguide. In particular, we observe that the injected light creates a bottleneck in the film and part of the injected light is refracted leading to whiskers. At the end of the drainage where the film thickness is below 1μm, there is a strong selection among the various possible optical modes in the film, and part of the light is defiected. This leads to a self selection of the mode propagation inside the film.

  2. Biaxial stretching of film principles and applications

    CERN Document Server

    Demeuse, M T

    2011-01-01

    Biaxial (having two axes) stretching of film is used for a range of applications and is the primary manufacturing process by which products are produced for the food packaging industry. Biaxial stretching of film: principles and applications provides an overview of the manufacturing processes and range of applications for biaxially stretched films. Part one reviews the fundamental principles of biaxial stretching. After an introductory chapter which defines terms, chapters discuss equipment design and requirements, laboratory evaluations, biaxial film structures and typical industrial processes for the biaxial orientation of films. Additional topics include post production processing of biaxially stretched films, the stress-strain behaviour of poly(ethylene terephthalate) and academic investigations of biaxially stretched films. Part two investigates the applications of biaxial films including fresh cut produce, snack packaging and product labelling. A final chapter investigates potential future trends for bi...

  3. Film for Non-Formal Education.

    Science.gov (United States)

    Jenkins, Janet

    1979-01-01

    Looks at educational factors in using television or cinema film for non-formal education in developing nations. Styles of presentation in films are discussed, and suggestions are made for assessing effectiveness. (JEG)

  4. Transparent conducting film: Effect of mechanical stretching

    Indian Academy of Sciences (India)

    We describe in this paper a transparent conducting film (TCF). ... conducting carbon nanotube film which is crack-resistant for solar cell applications. ... CA 90095, USA; Nanocomp Technologies, Inc, 162 Pembroke Road, Concord, NH 03301 ...

  5. New ISO standard - personnel photographic film dosemeters

    International Nuclear Information System (INIS)

    Brabec, D.

    1980-01-01

    The ISO Standard 1757 ''Personnel Photographic Film Dosemeters'', issued in June 1980, is briefly described. UVVVR's own dosemeter developed for use in the national film dosimetry service in Czechoslovakia is evaluated in relation to this ISO Standard. (author)

  6. Public invited to Appalachian Studies Film Series

    OpenAIRE

    Elliott, Jean

    2004-01-01

    The Appalachian Studies Program at Virginia Tech is hosting a series of notable artistic and documentary films. The films deal with themes or issues covered in Appalachian Studies courses and are organized historically, touching upon issues common to all Appalachians.

  7. An intelligence ink for photocatalytic films.

    Science.gov (United States)

    Mills, Andrew; Wang, Jishun; Lee, Soo-Keun; Simonsen, Morten

    2005-06-07

    An ink is described which, when printed or coated onto a photocatalyst film, changes colour irreversibly and rapidly upon UV activation of the photocatalyst film and at a rate commensurate with its activity.

  8. X-ray film calibration

    International Nuclear Information System (INIS)

    Stone, G.F.; Dittmore, C.H.; Henke, B.L.

    1986-01-01

    This paper discusses the use of silver halide x-ray films for imaging and spectroscopy which is limited by the range of intensities that can be recorded and densitometered. Using the manufacturers processing techniques can result in 10 2-3 range in intensity recorded over 0-5 density range. By modifying the chemistry and processing times, ranges of 10 5-6 can be recorded in the same density range. The authors report on x-ray film calibration work and dynamic range improvements. Changes to the processing chemistry and the resulting changes in dynamic range and x-ray sensitivity are discussed

  9. Films--Too Good for Words. A Directory of Nonnarrated 16mm Films.

    Science.gov (United States)

    Parlato, Salvatore J., Jr.

    A nonnarrated film is one that communicates pictorially on the strength of its visual unity, continuity, and coherence without relying on narration or dialogue. This directory lists 1,000 such 16mm films, mostly curriculum-oriented educational films, in three main parts. The first part describes films under subject headings such as the arts, other…

  10. Spectator's trust as an indicator of film authorship: Is Vinterberg a film auteur?

    NARCIS (Netherlands)

    van der Pol, G.

    2015-01-01

    In this article, the Trust Model is presented as a new theory to tackle the old film theoretical problem of distinguishing film directors from film auteurs. The model proposes that in certain films, the spectator becomes problematically engaged to the fiction and to certain characters. During the

  11. Predictors of Horror Film Attendance and Appeal: An Analysis of the Audience for Frightening Films.

    Science.gov (United States)

    Tamborini, Ron; Stiff, James

    1987-01-01

    Analyzes the appeal of horror films. Develops a model that finds that important factors in the horror film's appeal are the audience's desire to experience the satisfying resolutions and to see the destruction usually found in these films and the sensation-seeking personality traits of audience members for these films. (NKA)

  12. Perkembangan Motif Sineas Film Indie dalam Menghadapi Industri Film Mainstream

    Directory of Open Access Journals (Sweden)

    Yoppy Ardiyono

    2016-03-01

    Full Text Available The research aims to review to review determine the effect and its impact raised by motive - a motive the ada in the hearts period travel time history of film short against cinematographer-filmmaker as principal especially filmmakers left path (indie. The used platform theory research hearts singer adopts from theory commodification media vincent mosco. Singer helped shift theory understanding the motive filmmakers working hearts differences fundamental basis of political pressure economic happens under with demands regime. The method used is descriptive qualitative research methods. Data collection techniques through observation of the environment of an independent film live and in-depth interviews with speakers including mr. Yang prayer orangutan direct contact 'with realm of research. Coupled with study to review the literature references adding insight research. And that was concluded change appears motif among indie film cinematographer it is true the situation is closely linked to the mainstream industry, konstilasi politics, and the orientation of capitalism. Necessary their one thing is clear and systematic regulation from the government to the future movement of currents sidestream (indie more with good operates professionally arranged, the air so that the contribution of indie cinema film land for progress can feels good to yourself indie filmmakers as well as those of its main industries.

  13. The Argument in Film: Applying Rhetorical Theory to Film Criticism.

    Science.gov (United States)

    Behrens, Laurence

    1979-01-01

    Approaches film criticism using classical and modern rhetorical concepts. Discusses the nature and effectiveness of the filmmaker's modes of appeal--to logos, pathos, and ethos, and the appropriateness of his/her rhetorical stance--the balance of attitudes toward subject, audience, and his/her creative self. (JMF)

  14. Film Music: Implications for Instructional Films and Television.

    Science.gov (United States)

    Hlynka, D.

    This paper provides a critical review of the behavioral research on film music, indicates that there is a visual bias in media attribute research which needs to be balanced, and provides media producers and instructional developers with a theoretical basis and practical guidelines for using music in audiovisual presentations. The question of film…

  15. Cinematography; A Guide for Film Makers and Film Teachers.

    Science.gov (United States)

    Malkiewicz, J. Kris

    Concentrating on the work of the cinematographer--the man behind the camera or in charge of the shooting--this book also touches on techniques of sound recording, cutting, and production logistics. Technical discussions designed to provide the basic principles and techniques of cinematography are presented about cameras, films and sensitometry,…

  16. PVA-based nanographene film by electrospinning

    Directory of Open Access Journals (Sweden)

    Pang Jing

    2013-01-01

    Full Text Available Two-dimensional polyvinyl alcohol based graphene films with the thickness of less than 20 nm were fabricated directly by using polyvinyl alcohol/graphite solution or polyvinyl alcohol/ash solution by electrospinning. It was found that ash particles are good candidate for substitution of graphite particles to fabricate nanographene films. The relationship between the thickness and width of the film is elucidated, and the periodic morphology of the film is explained.

  17. Nanocrystal thin film fabrication methods and apparatus

    Science.gov (United States)

    Kagan, Cherie R.; Kim, David K.; Choi, Ji-Hyuk; Lai, Yuming

    2018-01-09

    Nanocrystal thin film devices and methods for fabricating nanocrystal thin film devices are disclosed. The nanocrystal thin films are diffused with a dopant such as Indium, Potassium, Tin, etc. to reduce surface states. The thin film devices may be exposed to air during a portion of the fabrication. This enables fabrication of nanocrystal-based devices using a wider range of techniques such as photolithography and photolithographic patterning in an air environment.

  18. Representasi Homoseksualitas dalam Film Indonesia Kontemporer

    OpenAIRE

    Maimunah Maimunah

    2007-01-01

    This paper examines the emergence of non-normative sexual orientations in contemporary Indonesian films. Unlike the representation of sexuality in New Order Indonesian films, which centred on the female reproductive role and presented the nation as constructed of heterosexual families rather than individual citizens, a number of 200()s Indonesian films can be seen as negotiations of new understandings of sexual diversity and individual subjectivity. These films represent a challenge to monoli...

  19. Representasi Homoseksualitas Dalam Film Indonesia Kontemporer

    OpenAIRE

    Maimunah, Maimunah

    2007-01-01

    This paper examines the emergence of non-normative sexual orientations in contemporary Indonesian films. Unlike the representation of sexuality in New Order Indonesian films, which centred on the female reproductive role and presented the nation as constructed of heterosexual families rather than individual citizens, a number of 200()s Indonesian films can be seen as negotiations of new understandings of sexual diversity and individual subjectivity. These films represent a challenge to monoli...

  20. Video enhancement of dental radiographic films

    International Nuclear Information System (INIS)

    Van Dis, M.L.; Beck, F.M.; Miles, D.A.

    1989-01-01

    A prototype video image display system, a real-time analog enhancer (RAE), was compared to conventional viewing conditions with the use of nonscreen dental films. When medium optical density films were evaluated, there was no significant difference in the number of radiographic details detected. Conventional viewing conditions allowed perception of more details when dark films were evaluated; however, the RAE unit allowed the perception of more details when light films were viewed

  1. Avant-Garde Film: Cinema as Discourse.

    Science.gov (United States)

    MacDonald, Scott

    1988-01-01

    Considers the state of the avant-garde film movement. Contends that for those who are convinced of the potential importance of the broadest articulation of cinema, it is necessary to demonstrate the excitement and value of using avant-garde films in a wide range of academic contexts and as one of academic film activity's essential components. (MS)

  2. Päeva film / Tiit Merisalu

    Index Scriptorium Estoniae

    Merisalu, Tiit

    1997-01-01

    Autobiograafiline film "Maffia ja mina" ("Mafia ja minä"), režissöör Tuomas Sallinen : Soome 1997. Film jälgib toimunud sündmuste käiku päeviku vormis ja on tehtud osalt intervjuudena, osalt lavastatud episoodidena. Film on valminud sarjas "Uus kino"

  3. Film sound in preservation and presentation

    NARCIS (Netherlands)

    Campanini, S.

    2014-01-01

    What is the nature of film sound? How does it change through time? How can film sound be conceptually defined? To address these issues, this work assumes the perspective of film preservation and presentation practices, describing the preservation of early sound systems, as well as the presentation

  4. Film Language: A Student-Made Dictionary.

    Science.gov (United States)

    Poteet, G. Howard

    1967-01-01

    The failure of verbal descriptions to convey an understanding of film terminology led to a student production of a 20-minute color film that defines various film methods by illustrating them. A technique is shown on the screen and simultaneous soundtrack narration explains how this technique can be used. When the narration lasts longer than the…

  5. Fruit and vegetable films and uses thereof

    Science.gov (United States)

    The present invention is directed to monolayer, bilayer, and multilayer films made from fruit, vegetable or a combination thereof, which films have the thinness, strength, flexibility and crispness to serve as alternates or substitutes for seaweed-based films such as nori, while providing nutrition ...

  6. Shakespeare on Film in the Classroom.

    Science.gov (United States)

    Mullin, Michael

    A course at the University of Illinois entitled "Shakespeare on Film" is discussed briefly, and an annotated list of Shakespeare films for the classroom teacher is provided in this paper. Thirteen films are listed: three versions of "Hamlet,""Henry V,""Julius Caesar," four versions of…

  7. 21 CFR 892.1840 - Radiographic film.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiographic film. 892.1840 Section 892.1840 Food... DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1840 Radiographic film. (a) Identification. Radiographic film is a device that consists of a thin sheet of radiotransparent material coated on one or both...

  8. Method of producing thin cellulose nitrate film

    International Nuclear Information System (INIS)

    Lupica, S.B.

    1975-01-01

    An improved method for forming a thin nitrocellulose film of reproducible thickness is described. The film is a cellulose nitrate film, 10 to 20 microns in thickness, cast from a solution of cellulose nitrate in tetrahydrofuran, said solution containing from 7 to 15 percent, by weight, of dioctyl phthalate, said cellulose nitrate having a nitrogen content of from 10 to 13 percent

  9. [Psychopathology and film: a valuable interaction?].

    Science.gov (United States)

    van Duppen, Z; Summa, M; Fuchs, T

    2015-01-01

    Film or film fragments are often used in psychopathology education. However, so far there have been very few articles that have discussed the benefits and limitations of using films to explain or illustrate psychopathology. Although numerous films involves psychopathology in varying degrees, it is not clear how we can use films for psychopathology education. To examine the advantages, limitations and possible methods of using film as a means of increasing our knowledge and understanding of psychiatric illnesses. We discuss five examples that illustrate the interaction of film and psychopathology. On the one hand we explain how the psychopathological concepts are used in each film and on the other hand we explain which aspects of each film are valuable aids for teaching psychopathology. The use of film makes it possible to introduce the following topics in psychopathological teaching programme: holistic psychiatric reasoning, phenomenology and the subjective experience, the recognition of psychopathological prototypes and the importance of context. There is undoubtedly an analogy between the method we have chosen for teaching psychopathology with the help of films and the holistic approach of the psychiatrist and his or her team. We believe psychopathology education can benefit from films and we would recommend our colleagues to use it in this way.

  10. Perceiving Event Dynamics and Parsing Hollywood Films

    Science.gov (United States)

    Cutting, James E.; Brunick, Kaitlin L.; Candan, Ayse

    2012-01-01

    We selected 24 Hollywood movies released from 1940 through 2010 to serve as a film corpus. Eight viewers, three per film, parsed them into events, which are best termed subscenes. While watching a film a second time, viewers scrolled through frames and recorded the frame number where each event began. Viewers agreed about 90% of the time. We then…

  11. Characterization of nanocrystalline cadmium telluride thin films ...

    Indian Academy of Sciences (India)

    Unknown

    tion method, successive ionic layer adsorption and reaction (SILAR), are described. For deposition of CdTe thin films ... By conducting several trials optimization of the adsorption, reaction and rinsing time duration for CdTe thin film .... The electrical resistivity of CdTe films was studied in air. Figure 3 shows the variation of log ...

  12. Europa Heute: Filmbegleitheft (Europe Today: Film Manual).

    Science.gov (United States)

    Freudenstein, Reinhold; And Others

    This teacher's guide to the German promotional film "Europe Today", suitable for use in advanced courses, concentrates on linguistic preparation required for full appreciation. The film focuses on the role of European countries as participating members of the Common Market. The manual includes information on the German film industry, a…

  13. The Film Book Bibliography 1940-1975.

    Science.gov (United States)

    Ellis, Jack C.; And Others

    More than 5,400 entries are included in this first attempt to cite and classify all English language books, monographs, and dissertations about film that appeared from 1940 to 1975. Intended as a source of information about existing film books and as a tool for researching available literature on any film topic, the bibliography uses ten basic…

  14. The Historian Encounters Film: A Historiography.

    Science.gov (United States)

    Toplin, Robert Brent; Eudy, Jason

    2002-01-01

    Provides a historiography of the articles and books that focuses upon studying history through film. Reviews topics such as: censorship, the film industry's use and interpretations of history in films, and the lack of material on documentaries in the scholarship. (CMK)

  15. A Study on Environmental Education Films.

    Science.gov (United States)

    Gerba, Diana

    The degree of communication between the film industry and educators and its effect on the future directions of environmental education films are the focus of this report. Separate surveys were mailed to 100 film industry producers and distributors and 150 elementary and secondary educators in Maine, Kansas, Pennsylvania, California, and Alabama.…

  16. doped ZnO thick film resistors

    Indian Academy of Sciences (India)

    The characterization and ethanol gas sensing properties of pure and doped ZnO thick films were investigated. Thick films of pure zinc oxide were prepared by the screen printing technique. Pure zinc oxide was almost insensitive to ethanol. Thick films of Al2O3 (1 wt%) doped ZnO were observed to be highly sensitive to ...

  17. Script Design for Information Film and Video.

    Science.gov (United States)

    Shelton, S. M. (Marty); And Others

    1993-01-01

    Shows how the empathy created in the audience by each of the five genres of film/video is a function of the five elements of film design: camera angle, close up, composition, continuity, and cutting. Discusses film/video script designing. Illustrates these concepts with a sample script and story board. (SR)

  18. Special equipment for etching nitrocellulose film

    International Nuclear Information System (INIS)

    Domanus, J.C.

    1983-08-01

    Nitrocellulose film and converter screens used for neutron radiography are described. Difficulties in visualization of radiographs on those films are mentioned. Because there is no equipment for etching nitrocellulose film available on the market Risoe has designed and produced such equipment at an estimated cost of Dkr. 15,000. Design criteria for this equipment are given and its performance described

  19. Federal Judge Orders Showing of Controversial Film.

    Science.gov (United States)

    Flygare, Thomas J.

    1987-01-01

    Reviews a recent court decision in Nebraska regarding the cancellation of a controversial film on the University of Nebraska campus. The film was cancelled after a state senator threatened to close the theater if the movie was shown. The lawsuit alleged the university violated the First Amendment in cancelling the film; the judge ruled for the…

  20. Properties of sericin films crosslinking with dimethylolurea

    International Nuclear Information System (INIS)

    Turbiani, Franciele R.B.; Stroher, Gylles Ricardo; Tomadon Junior, Jose; Seixas, Fernanda L.; Stroher, Gylles Ricardo; Gimenes, Marcelino L.

    2011-01-01

    Sericin is a natural silk protein which is removed from silk in a process called degumming. Thus, finding a use for the extracted sericin as a bio polymer film will create added value product which will benefit both the economy and society. The films were manufactured with silk sericin, using different dimethylolurea (DMU) concentrations as cross-linking agent and glycerol as plasticizer. Sericin films produced by crosslinking method were light yellow, homogeneous, transparent and visually attractive. The average film thickness was 0.10 ± 0.02 mm. The bio films show low water solubility (up to 30% of total dry mass), good tension strength and high elongation ability. The water vapor permeability is moderate, typical of highly hydrophilic films. Structural transformations in silk sericin films were analyzed using Fourier transform infrared-attenuated total reflection (FTIR-ATR) spectroscopy and X-ray diffraction. This resulted in aggregated β-sheet structure (peak at 1616 cm-1 in the amide I absorption) by FTIR studies and increasing the DMU concentration in film decreased the peak intensity at 2θ = 20 degree. Sericin-based film properties are dependent on components used to form film, which can used to tailor the desired film flexibility and minimize permeability of films. (author)

  1. Polyvinylidene fluoride film as a capacitor dielectric

    Science.gov (United States)

    Dematos, H. V.

    1981-01-01

    Thin strips of polyvinylidene fluoride film (PVDF) with vacuum deposited electrodes were made into capacitors by conventional winding and fabrication techniques. These devices were used to identify and evaluate the performance characteristics offered by the PVDF in metallized film capacitors. Variations in capacitor parameters with temperature and frequence were evaluated and compared with other dielectric films. Their impact on capacitor applications is discussed.

  2. Staging the Amateur Film Dispositif (video)

    NARCIS (Netherlands)

    van der Heijden, T.

    2014-01-01

    A media archaeological experiment performed on March 31st 2014, at the 9th International Orphan Film Symposium, EYE Film Institute Amsterdam. In the performance we reconstruct the changing 'dispositif' of home movie screening practices. In three ‘tableaux’ we explore how past media usages of film,

  3. Film and the Young Adult Novel.

    Science.gov (United States)

    Foster, Harold M.

    1994-01-01

    Discusses films based on young adult novels and why they are often considered failures. Describes various films about young adults and their problems that have proven to be artistic successes. Gives close attention to film versions of S. E. Hinton's novels and of Robert Cormier's "The Chocolate War." (HB)

  4. Teaching World Music through Feature Films

    Science.gov (United States)

    Lum, Chee-Hoo

    2009-01-01

    When used effectively, feature films can bring a plethora of visual and aural stimulation to students and enhance their learning about world cultures. Feature films can take students to places, sights, and sounds that they have yet to experience. After watching these films, students might become new admirers or even keen followers of the subject…

  5. The Enthymeme and Contemporary Film Criticism.

    Science.gov (United States)

    Arnett, Robert

    Aristotle's "Rhetoric" offers a model for applying the concept of the enthymeme to the work of film scholars to understand the role of the audience. Used from an analytic perspective, enthymemes emphasize audience reaction to a film, with the focus on how the film is seen, not on how it was made. Applying viewing skills to a sample of…

  6. Lithium insertion in sputtered vanadium oxide film

    DEFF Research Database (Denmark)

    West, K.; Zachau-Christiansen, B.; Skaarup, S.V.

    1992-01-01

    were oxygen deficient compared to V2O5. Films prepared in pure argon were reduced to V(4) or lower. The vanadium oxide films were tested in solid-state lithium cells. Films sputtered in oxygen showed electrochemical properties similar to crystalline V2O5. The main differences are a decreased capacity...

  7. Properties of sericin films crosslinking with dimethylolurea

    Energy Technology Data Exchange (ETDEWEB)

    Turbiani, Franciele R.B.; Stroher, Gylles Ricardo [Federal Technology University - UTFPR, Campus Apucarana, PR (Brazil); Tomadon, Junior, Jose; Seixas, Fernanda L; Stroher, Gylles Ricardo; Gimenes, Marcelino L., E-mail: francieler@utfpr.edu.br [State University of Maringa. UEM, Campus Maringa, PR (Brazil)

    2011-07-01

    Sericin is a natural silk protein which is removed from silk in a process called degumming. Thus, finding a use for the extracted sericin as a bio polymer film will create added value product which will benefit both the economy and society. The films were manufactured with silk sericin, using different dimethylolurea (DMU) concentrations as cross-linking agent and glycerol as plasticizer. Sericin films produced by crosslinking method were light yellow, homogeneous, transparent and visually attractive. The average film thickness was 0.10 {+-} 0.02 mm. The bio films show low water solubility (up to 30% of total dry mass), good tension strength and high elongation ability. The water vapor permeability is moderate, typical of highly hydrophilic films. Structural transformations in silk sericin films were analyzed using Fourier transform infrared-attenuated total reflection (FTIR-ATR) spectroscopy and X-ray diffraction. This resulted in aggregated {beta}-sheet structure (peak at 1616 cm-1 in the amide I absorption) by FTIR studies and increasing the DMU concentration in film decreased the peak intensity at 2{theta} = 20 degree. Sericin-based film properties are dependent on components used to form film, which can used to tailor the desired film flexibility and minimize permeability of films. (author)

  8. ZnO film deposition on Al film and effects of deposition temperature on ZnO film growth characteristics

    International Nuclear Information System (INIS)

    Yoon, Giwan; Yim, Munhyuk; Kim, Donghyun; Linh, Mai; Chai, Dongkyu

    2004-01-01

    The effects of the deposition temperature on the growth characteristics of the ZnO films were studied for film bulk acoustic wave resonator (FBAR) device applications. All films were deposited using a radio frequency magnetron sputtering technique. It was found that the growth characteristics of ZnO films have a strong dependence on the deposition temperature from 25 to 350 deg. C. ZnO films deposited below 200 deg. C exhibited reasonably good columnar grain structures with highly preferred c-axis orientation while those above 200 deg. C showed very poor columnar grain structures with mixed-axis orientation. This study seems very useful for future FBAR device applications

  9. Evaluation and mitigation of potential errors in radiochromic film dosimetry due to film curvature at scanning.

    Science.gov (United States)

    Palmer, Antony L; Bradley, David A; Nisbet, Andrew

    2015-03-08

    This work considers a previously overlooked uncertainty present in film dosimetry which results from moderate curvature of films during the scanning process. Small film samples are particularly susceptible to film curling which may be undetected or deemed insignificant. In this study, we consider test cases with controlled induced curvature of film and with film raised horizontally above the scanner plate. We also evaluate the difference in scans of a film irradiated with a typical brachytherapy dose distribution with the film naturally curved and with the film held flat on the scanner. Typical naturally occurring curvature of film at scanning, giving rise to a maximum height 1 to 2 mm above the scan plane, may introduce dose errors of 1% to 4%, and considerably reduce gamma evaluation passing rates when comparing film-measured doses with treatment planning system-calculated dose distributions, a common application of film dosimetry in radiotherapy. The use of a triple-channel dosimetry algorithm appeared to mitigate the error due to film curvature compared to conventional single-channel film dosimetry. The change in pixel value and calibrated reported dose with film curling or height above the scanner plate may be due to variations in illumination characteristics, optical disturbances, or a Callier-type effect. There is a clear requirement for physically flat films at scanning to avoid the introduction of a substantial error source in film dosimetry. Particularly for small film samples, a compression glass plate above the film is recommended to ensure flat-film scanning. This effect has been overlooked to date in the literature.

  10. Representasi Perempuan Dalam Film (Analisis Semiotika Representasi Perempuan Dalam Film “Fifty Shades of Grey”)

    OpenAIRE

    Aviomeita, Friska

    2016-01-01

    This study entitled "Representation of Women In Film ( Roland Barthes Semiotics Analysis In the film Fifty Shades of Grey ) " . The purpose of this study to find out how women are represented in the film " Fifty Shades of Grey " by denotation , connotation and myths . Film has always influenced and shaped the public based on the contents of the message behind it. Messages or values contained in the film may affect the audience. In this study, researchers used several theorie...

  11. Veneetsias esilinastus uus Madonna film

    Index Scriptorium Estoniae

    2011-01-01

    Väljaspool võistlust linastub Veneetsia filmifestivalil Madonna film "W.E.". Ka Katusekinos esietenduvast tantsulavastusest "Lost at Midnight"; "Legend vägevast seebist" maailmaesilinastusest Austinis, Texases toimuval filmifestivalil Fantastic Fest; Katusekinos 9. sept. toimuvast üritusest PechaKucha

  12. Viscosity of particle laden films

    Directory of Open Access Journals (Sweden)

    Timounay Yousra

    2017-01-01

    Full Text Available We perform retraction experiments on soap films where large particles bridge the two interfaces. Local velocities are measured by PIV during the unstationnary regime. The velocity variation in time and space can be described by a continuous fluid model from which effective viscosity (shear and dilatational of particulate films is measured. The 2D effective viscosity of particulate films η2D increases with particle surface fraction ϕ: at low ϕ, it tends to the interfacial dilatational viscosity of the liquid/air interfaces and it diverges at the critical particle surface fraction ϕc ≃ 0.84. Experimental data agree with classical viscosity laws of hard spheres suspensions adapted to the 2D geometry, assuming viscous dissipation resulting from the squeeze of the liquid/air interfaces between the particles. Finally, we show that the observed viscous dissipation in particulate films has to be considered to describe the edge velocity during a retraction experiment at large particle coverage.

  13. (MAA:EA) copolymer films

    Indian Academy of Sciences (India)

    2017-08-16

    Aug 16, 2017 ... behaviour. The interaction between oppositely charged poly- ... methods to improve the ionic conductivity, optical proper- ties, mechanical and ... liquid, filler and mixed salt systems [10,11]. Based on the ... multiple ways of preparing Cu2+ based polymer thin films. The Cu2+ ion ..... A broad and very strong.

  14. Learning about Teachers through Film.

    Science.gov (United States)

    Raimo, Angela; Devlin-Scherer, Roberta; Zinicola, Debra

    2002-01-01

    Analysis of films featuring teachers reveals a variety of roles portrayed: teacher as culture guardian, iconoclast/subverter, alien culture-bearer, change agent, learner, compassionate mentor, student advocate, maverick, and incompetent. Examination of these portrayals can prompt critical thinking about teacher responses to different social and…

  15. Stress in hard metal films

    NARCIS (Netherlands)

    Janssen, G.C.A.M.; Kamminga, J.D.

    2004-01-01

    In the absence of thermal stress, tensile stress in hard metal films is caused by grain boundary shrinkage and compressive stress is caused by ion peening. It is shown that the two contributions are additive. Moreover tensile stress generated at the grain boundaries does not relax by ion

  16. Kinetic phenomena in Sc films

    International Nuclear Information System (INIS)

    Stasyuk, Z.V.

    1992-01-01

    Size effects in electrical conductivity, thermoelectric power and Hall coefficient of thin scandium films have been investigated. An analysis of experimental data was made within the framework of Mayadas-Shatzkes and Tellier-Tosser-Pichard models. The transport parameters of scandium have been found. (author)

  17. Falling films on flexible inclines

    Science.gov (United States)

    Matar, O. K.; Craster, R. V.; Kumar, S.

    2007-11-01

    The nonlinear stability and dynamic behavior of falling fluid films is studied for flow over a flexible substrate. We use asymptotic methods to deduce governing equations valid in various limits. Long-wave theory is used to derive Benney-like coupled equations for the film thickness and substrate deflection. Weakly nonlinear equations are then derived from these equations that, in the limit of large wall damping and/or large wall tension, reduce to the Kuramoto-Sivashinsky equation. These models break down when inertia becomes more significant, so we also use a long-wave approximation in conjunction with integral theory to derive three strongly coupled nonlinear evolution equations for the film thickness, substrate deflection, and film volumetric flow rate valid at higher Reynolds numbers. These equations, accounting for inertia, capillary, viscous, wall tension, and damping effects, are solved over a wide range of parameters. Our results suggest that decreasing wall damping and/or wall tension can promote the development of chaos in the weakly nonlinear regime and lead to severe substrate deformations in the strongly nonlinear regime; these can give rise to situations in which the free surface and underlying substrate come into contact in finite time.

  18. Teaching Bank Runs through Films

    Science.gov (United States)

    Flynn, David T.

    2009-01-01

    The author advocates the use of films to supplement textbook treatments of bank runs and panics in money and banking or general banking classes. Modern students, particularly those in developed countries, tend to be unfamiliar with potential fragilities of financial systems such as a lack of deposit insurance or other safety net mechanisms. Films…

  19. Flexible thin film magnetoimpedance sensors

    International Nuclear Information System (INIS)

    Kurlyandskaya, G.V.; Fernández, E.; Svalov, A.; Burgoa Beitia, A.; García-Arribas, A.; Larrañaga, A.

    2016-01-01

    Magnetically soft thin film deposited onto polymer substrates is an attractive option for flexible electronics including magnetoimpedance (MI) applications. MI FeNi/Ti based thin film sensitive elements were designed and prepared using the sputtering technique by deposition onto rigid and flexible substrates at different deposition rates. Their structure, magnetic properties and MI were comparatively analyzed. The main structural features were sufficiently accurately reproduced in the case of deposition onto cyclo olefine polymer substrates compared to glass substrates for the same conditions. Although for the best condition (28 nm/min rate) of the deposition onto polymer a significant reduction of the MI field sensitivity was found satisfactory for sensor applications sensitivity: 45%/Oe was obtained for a frequency of 60 MHz. - Highlights: • [FeNi/Ti] 3 /Cu/[FeNi/Ti] 3 films were prepared by sputtering at different deposition rates. • Polymer substrates insure sufficiently accurate reproducibility of the film structure. • High deposition rate of 28 nm/min insures the highest values of the magnetoimpedance sensitivity. • Deposition onto polymer results in the satisfactory magnetoimpedance sensitivity of 45%/Oe.

  20. Flexible thin film magnetoimpedance sensors

    Energy Technology Data Exchange (ETDEWEB)

    Kurlyandskaya, G.V., E-mail: galina@we.lc.ehu.es [Universidad del País Vasco, UPV/EHU, Departamento de Electricidad y Electrónica, P.O. Box 644, Bilbao 48080 (Spain); Ural Federal University, Laboratory of Magnetic sensoric, Lenin Ave. 51, 620083 Ekaterinburg (Russian Federation); Fernández, E. [BCMaterials UPV-EHU, Vizcaya Science and Technology Park, 48160 Derio (Spain); Svalov, A. [Universidad del País Vasco, UPV/EHU, Departamento de Electricidad y Electrónica, P.O. Box 644, Bilbao 48080 (Spain); Ural Federal University, Laboratory of Magnetic sensoric, Lenin Ave. 51, 620083 Ekaterinburg (Russian Federation); Burgoa Beitia, A. [Universidad del País Vasco, UPV/EHU, Departamento de Electricidad y Electrónica, P.O. Box 644, Bilbao 48080 (Spain); García-Arribas, A. [Universidad del País Vasco, UPV/EHU, Departamento de Electricidad y Electrónica, P.O. Box 644, Bilbao 48080 (Spain); BCMaterials UPV-EHU, Vizcaya Science and Technology Park, 48160 Derio (Spain); Larrañaga, A. [SGIker, Servicios Generales de Investigación, Universidad del País Vasco (UPV/EHU), 48080 Bilbao (Spain)

    2016-10-01

    Magnetically soft thin film deposited onto polymer substrates is an attractive option for flexible electronics including magnetoimpedance (MI) applications. MI FeNi/Ti based thin film sensitive elements were designed and prepared using the sputtering technique by deposition onto rigid and flexible substrates at different deposition rates. Their structure, magnetic properties and MI were comparatively analyzed. The main structural features were sufficiently accurately reproduced in the case of deposition onto cyclo olefine polymer substrates compared to glass substrates for the same conditions. Although for the best condition (28 nm/min rate) of the deposition onto polymer a significant reduction of the MI field sensitivity was found satisfactory for sensor applications sensitivity: 45%/Oe was obtained for a frequency of 60 MHz. - Highlights: • [FeNi/Ti]{sub 3}/Cu/[FeNi/Ti]{sub 3} films were prepared by sputtering at different deposition rates. • Polymer substrates insure sufficiently accurate reproducibility of the film structure. • High deposition rate of 28 nm/min insures the highest values of the magnetoimpedance sensitivity. • Deposition onto polymer results in the satisfactory magnetoimpedance sensitivity of 45%/Oe.