WorldWideScience

Sample records for plasma thermal-desorption creation

  1. Determination of metformin in mouse, rat, dog and human plasma samples by laser diode thermal desorption/atmospheric pressure chemical ionization tandem mass spectrometry.

    Science.gov (United States)

    Swales, John G; Gallagher, Richard; Peter, Raimund M

    2010-11-02

    A simple, rapid and robust high-throughput assay for the quantitative analysis of metformin in plasma from different species using laser diode thermal desorption interfaced with atmospheric chemical pressure ionization tandem mass spectrometry (LDTD-APCI-MSMS) was developed for use in a pharmaceutical discovery environment. In order to minimize sample preparation a generic protein precipitation method was used to extract metformin from the plasma. Laser diode thermal desorption is a relatively new sample introduction method, the optimization of the instrumental parameters are presented. The method was successfully applied to spiked mouse, rat, dog and human plasma samples and was subsequently used to determine the oral pharmacokinetics of metformin after dosing to male rats in order to support drug discovery projects. The deviations for intra-assay accuracy and precision across the four species were less than 30% at all calibration and quality control levels.

  2. Thermal Desorption of Helium Implanted in Tungsten at RT

    Institute of Scientific and Technical Information of China (English)

    ZHANGFu; XUZengyu; LIUXiang; CHENJiming; XUYing; N.Yoshida; H.Iwakiri

    2002-01-01

    Tungsten is envisaged as one of the main candidate materials for divertor plate of ITER and future fusion reactors. Due to D-T reaction, PFMs would suffer helium irradiation from plasma additional to the high heat loads. Helium retention and thermal desorption behavior are largely concerned.

  3. Pair creation and plasma oscillations.

    Energy Technology Data Exchange (ETDEWEB)

    Prozorkevich, A. V.; Vinnik, D. V.; Schmidt, S. M.; Hecht, M. B.; Roberts, C. D.

    2000-12-15

    We describe aspects of particle creation in strong fields using a quantum kinetic equation with a relaxation-time approximation to the collision term. The strong electric background field is determined by solving Maxwell's equation in tandem with the Vlasov equation. Plasma oscillations appear as a result of feedback between the background field and the field generated by the particles produced. The plasma frequency depends on the strength of the initial background fields and the collision frequency, and is sensitive to the necessary momentum-dependence of dressed-parton masses.

  4. Fatty acid profiling of raw human plasma and whole blood using direct thermal desorption combined with gas chromatography-mass spectrometry

    NARCIS (Netherlands)

    Akoto, Lawrence; Vreuls, Rene J. J.; Irth, Hubertus; Pel, Roel; Stellaard, Frans

    2008-01-01

    Gas chromatography (GC) has in recent times become an important tool for the fatty acid profiling of human blood and plasma. An at-line procedure used in the fatty acid profiling of whole/intact aquatic micro-organisms without any sample preparation was adapted for this work. A direct thermal

  5. Fatty acid profiling of raw human plasma and whole blood using direct thermal desorption combined with gas chromatography–mass spectrometry

    NARCIS (Netherlands)

    Akoto, L.; Vreuls, R.J.J.; Irth, H.; Pel, R.; Stellaard, F.

    2008-01-01

    Gas chromatography (GC) has in recent times become an important tool for the fatty acid profiling of human blood and plasma. An at-line procedure used in the fatty acid profiling of whole/intact aquatic micro-organisms without any sample preparation was adapted for this work. A direct thermal

  6. Helium concentration measurement in tungsten fuzz-like nanostructures by means of thermal desorption spectroscopy

    NARCIS (Netherlands)

    Gasparyan, Y.; Efimov, V.; Bystrov, K.

    2016-01-01

    The concentration of helium in tungsten fuzz-like nanostructures has been measured by means of thermal desorption spectroscopy. Fuzz was formed on the W surface under intensive plasma irradiation at 1500 K. The helium content was measured first in the as-irradiated sample, and then in a similar samp

  7. Magic-angle thermal desorption mass spectroscopy

    Science.gov (United States)

    Pauls, Steven W.; Campbell, Charles T.

    1990-02-01

    Accurate quantitative measurements of desorption rates or adsorbate coverages in thermal desorption mass spectroscopy (TDS) using line-of-sight mass spectrometers are hindered by the fact that the angular distributions of desorption flux can vary widely from desorbate to desorbate, ranging from cos 1ø to cos 9 ø for most species studied to date (ø = polar angle from surface normal). These differences can easily lead to errors exceeding 400% in measuring the relative desorption rates of different species. We show here that, by placing the mass spectrometer's ion source or entrance aperture at a "magic-angle" ø mthese errors can be reduced to less than 26% maximum deviation (or ± 7% standard deviation). Depending upon the sample-to-detector distance, ø m varies from ~ 42° to 34°. It is recommended that TDS experiments be performed at this "magic-angle" for improvement in the quantitative accuracy of coverage or rate measurements.

  8. Mercury speciation during in situ thermal desorption in soil

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chang Min, E-mail: cmpark80@gmail.com; Katz, Lynn E.; Liljestrand, Howard M.

    2015-12-30

    Highlights: • Impact of soil conditions on distribution and phase transitions of Hg was identified. • Metallic Hg was slowly transformed to Hg{sup 0} gas until the temperature reached 358.15 K. • Phase change of HgCl{sub 2(s)} completely occurred without decomposition at 335.15 K. • HgS remained solid in dry soil sharply decreased in the narrow temperature range. • Hg gas can be easily captured with higher vapor pressures of soil compositions. - Abstract: Metallic mercury (Hg{sup 0}) and its compounds are highly mobile and toxic environmental pollutants at trace level. In situ thermal desorption (ISTD) is one of the soil remediation processes applying heat and vacuum simultaneously. Knowledge of thermodynamic mercury speciation is imperative to understand the fate and transport of mercury during thermal remediation and operate the treatment processes in a cost-effective manner. Hence, speciation model for inorganic mercury was developed over a range of environmental conditions to identify distribution of dissolved mercury species and potential transformations of mercury at near source environment. Simulation of phase transitions for metallic mercury, mercury(II) chloride and mercury sulfide with temperature increase showed that complete vaporization of metallic mercury and mercury(II) chloride were achieved below the boiling point of water. The effect of soil compositions on mercury removal was also evaluated to better understand thermal remediation process. Higher vapor pressures expected both from soil pore water and inorganic carbonate minerals in soil as well as creation of permeability were significant for complete vaporization and removal of mercury.

  9. Defect annealing and thermal desorption of deuterium in low dose HFIR neutron-irradiated tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Masashi Shimada; M. Hara; T. Otsuka; Y. Oya; Y. Hatano

    2014-05-01

    Accurately estimating tritium retention in plasma facing components (PFCs) and minimizing its uncertainty are key safety issues for licensing future fusion power reactors. D-T fusion reactions produce 14.1 MeV neutrons that activate PFCs and create radiation defects throughout the bulk of the material of these components. Recent studies show that tritium migrates and is trapped in bulk (>> 10 µm) tungsten beyond the detection range of nuclear reaction analysis technique [1-2], and thermal desorption spectroscopy (TDS) technique becomes the only established diagnostic that can reveal hydrogen isotope behavior in in bulk (>> 10 µm) tungsten. Radiation damage and its recovery mechanisms in neutron-irradiated tungsten are still poorly understood, and neutron-irradiation data of tungsten is very limited. In this paper, systematic investigations with repeated plasma exposures and thermal desorption are performed to study defect annealing and thermal desorption of deuterium in low dose neutron-irradiated tungsten. Three tungsten samples (99.99 at. % purity from A.L.M.T. Co., Japan) irradiated at High Flux Isotope Reactor at Oak Ridge National Laboratory were exposed to high flux (ion flux of (0.5-1.0)x1022 m-2s-1 and ion fluence of 1x1026 m-2) deuterium plasma at three different temperatures (100, 200, and 500 °C) in Tritium Plasma Experiment at Idaho National Laboratory. Subsequently, thermal desorption spectroscopy (TDS) was performed with a ramp rate of 10 °C/min up to 900 °C, and the samples were annealed at 900 °C for 0.5 hour. These procedures were repeated three (for 100 and 200 °C samples) and four (for 500 °C sample) times to uncover damage recovery mechanisms and its effects on deuterium behavior. The results show that deuterium retention decreases approximately 90, 75, and 66 % for 100, 200, and 500 °C, respectively after each annealing. When subjected to the same TDS recipe, the desorption temperature shifts from 800 °C to 600 °C after 1st annealing

  10. Electrostatic pair creation and recombination in quantum plasmas

    CERN Document Server

    Marklund, M; Shukla, P K; Stenflo, L; Dieckmann, M E; Parviainen, M

    2006-01-01

    The collective production of electron-positron pairs by electrostatic waves in quantum plasmas is investigated. In particular, a semi-classical governing set of equation for a self-consistent treatment of pair creation by the Schwinger mechanism in a quantum plasma is derived.

  11. The study of 'microsurfaces' using thermal desorption spectroscopy

    Science.gov (United States)

    Thomas, M. E.; Poppa, H.; Pound, G. M.

    1979-01-01

    The use of a newly combined ultrahigh vacuum technique for studying continuous and particulate evaporated thin films using thermal desorption spectroscopy (TDS), transmission electron microscopy (TEM), and transmission electron diffraction (TED) is discussed. It is shown that (1) CO thermal desorption energies of epitaxially deposited (111) Ni and (111) Pd surfaces agree perfectly with previously published data on bulk (111) single crystal, (2) contamination and surface structural differences can be detected using TDS as a surface probe and TEM as a complementary technique, and (3) CO desorption signals from deposited metal coverages of one-thousandth of a monolayer should be detectable. These results indicate that the chemisorption properties of supported 'microsurfaces' of metals can now be investigated with very high sensitivity. The combined use of TDS and TEM-TED experimental methods is a very powerful technique for fundamental studies in basic thin film physics and in catalysis.

  12. Spatially resolved thermal desorption/ionization coupled with mass spectrometry

    Science.gov (United States)

    Jesse, Stephen; Van Berkel, Gary J; Ovchinnikova, Olga S

    2013-02-26

    A system and method for sub-micron analysis of a chemical composition of a specimen are described. The method includes providing a specimen for evaluation and a thermal desorption probe, thermally desorbing an analyte from a target site of said specimen using the thermally active tip to form a gaseous analyte, ionizing the gaseous analyte to form an ionized analyte, and analyzing a chemical composition of the ionized analyte. The thermally desorbing step can include heating said thermally active tip to above 200.degree. C., and positioning the target site and the thermally active tip such that the heating step forms the gaseous analyte. The thermal desorption probe can include a thermally active tip extending from a cantilever body and an apex of the thermally active tip can have a radius of 250 nm or less.

  13. Defect annealing and thermal desorption of deuterium in low dose HFIR neutron-irradiated tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Shimada, Masashi, E-mail: Masashi.Shimada@inl.gov [Fusion Safety Program, Idaho National Laboratory, Idaho Falls, ID (United States); Hara, Masanori [Hydrogen Isotope Research Center, University of Toyama, Toyama (Japan); Otsuka, Teppei [Kyushu University, Interdisciplinary Graduate School of Engineering Science, Higashi-ku, Fukuoka (Japan); Oya, Yasuhisa [Radioscience Research Laboratory, Faculty of Science, Shizuoka University, Shizuoka (Japan); Hatano, Yuji [Hydrogen Isotope Research Center, University of Toyama, Toyama (Japan)

    2015-08-15

    Three tungsten samples irradiated at High Flux Isotope Reactor at Oak Ridge National Laboratory were exposed to deuterium plasma (ion fluence of 1 × 10{sup 26} m{sup −2}) at three different temperatures (100, 200, and 500 °C) in Tritium Plasma Experiment at Idaho National Laboratory. Subsequently, thermal desorption spectroscopy was performed with a ramp rate of 10 °C min{sup −1} up to 900 °C, and the samples were annealed at 900 °C for 0.5 h. These procedures were repeated three times to uncover defect-annealing effects on deuterium retention. The results show that deuterium retention decreases approximately 70% for at 500 °C after each annealing, and radiation damages were not annealed out completely even after the 3rd annealing. TMAP modeling revealed the trap concentration decreases approximately 80% after each annealing at 900 °C for 0.5 h.

  14. Thermal Desorption of Water-Ice in the Interstellar Medium

    CERN Document Server

    Fraser, H J; McCoustra, M R S; Williams, D A; Fraser, Helen J.; Collings, Mark P.; Coustra, Martin R.S. Mc; Williams, David A.

    2001-01-01

    Water (H2O) ice is an important solid constituent of many astrophysical environments. To comprehend the role of such ices in the chemistry and evolution of dense molecular clouds and comets, it is necessary to understand the freeze-out, potential surface reactivity, and desorption mechanisms of such molecular systems. Consequently, there is a real need from within the astronomical modelling community for accurate empirical molecular data pertaining to these processes. Here we give the first results of a laboratory programme to provide such data. Measurements of the thermal desorption of H2O ice, under interstellar conditions, are presented. For ice deposited under conditions that realistically mimic those in a dense molecular cloud, the thermal desorption of thin films (~50 molecular layers) is found to occur with zero order kinetics characterised by a surface binding energy, E_{des}, of 5773 +/- 60 K, and a pre-exponential factor, A, of 10^(30 +/- 2) molecules cm^-2 s^-1. These results imply that, in the den...

  15. Wheat Growth in Soils Treated by Ex Situ Thermal Desorption.

    Science.gov (United States)

    O'Brien, Peter L; DeSutter, Thomas M; Casey, Francis X M; Wick, Abbey F; Khan, E

    2017-07-01

    Successful remediation of oil-contaminated agricultural land may include the goal of returning the land to prespill levels of agricultural productivity. This productivity may be measured by crop yield, quality, and safety, all of which are influenced by soil characteristics. This research was conducted to determine if these metrics are affected in hard red spring wheat ( L. cultivar Barlow) when grown in soils treated by ex situ thermal desorption (TD) compared with wheat grown in native topsoil (TS). Additionally, TD soils were mixed with TS at various ratios to assess the effectiveness of soil mixing as a procedure for enhancing productivity. In two greenhouse studies, TD soils alone produced similar amounts of grain and biomass as TS, although grain protein in TD soils was 22% (±7%) lower. After mixing TS into TD soils, the mean biomass and grain yield were reduced by up to 60%, but grain protein increased. These trends are likely the result of nutrient availability determined by soil organic matter and nutrient cycling performed by soil microorganisms. Thermal desorption soil had 84% (±2%) lower soil organic carbon than TS, and cumulative respiration was greatly reduced (66 ± 2%). From a food safety perspective, grain from TD soils did not show increased uptake of polycyclic aromatic hydrocarbons. Overall, this research suggests that TD soils are capable of producing safe, high-quality grain yields. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  16. Laser-induced thermal desorption of aniline from silica surfaces

    Science.gov (United States)

    Voumard, Pierre; Zenobi, Renato

    1995-10-01

    A complete study on the energy partitioning upon laser-induced thermal desorption of aniline from silica surfaces was undertaken. The measurements include characterization of the aniline-quartz adsorption system using temperature-programmed desorption, the extrapolation of quasiequilibrium desorption temperatures to the regime of laser heating rates on the order of 109-1010 K/s by computational means, measurement of the kinetic energy distributions of desorbing aniline using a pump-probe method, and the determination of internal energies with resonance-enhanced multiphoton ionization spectroscopy. The measurements are compared to calculations of the surface temperature rise and the resulting desorption rates, based on a finite-difference mathematical description of pulsed laser heating. While the surface temperature of laser-heated silica reaches about 600-700 K at the time of desorption, the translational temperature of laser-desorbed aniline was measured to be Tkin=420±60 K, Tvib was 360±60 K, and Trot was 350±100 K. These results are discussed using different models for laser-induced thermal desorption from surfaces.

  17. Thermal desorption of PCBs from contaminated soil with copper dichloride.

    Science.gov (United States)

    Liu, Jie; Qi, Zhifu; Li, Xiaodong; Chen, Tong; Buekens, Alfons; Yan, Jianhua; Ni, Mingjiang

    2015-12-01

    Copper dichloride is an important catalyst both in the dechlorination of chlorinated aromatic compounds and the formation of PCDD/Fs. The effect of copper dichloride on polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) was studied in treated soil and off gas after thermal desorption of PCB-contaminated soil at 300, 400, 500, 600 °C. The presence of copper dichloride clearly enhances thermal desorption by promoting PCBs removal, destruction, and dechlorination. After thermal treatment at 600 °C for 1 h, the removal efficiency and destruction efficiency for PCBs reached 98.1 and 93.9%, respectively. Compared with the positive influence on PCBs, copper dichloride catalyzed large amount of PCDFs formation at 300 °C, with the concentration ratio of 2.35. The effect of CuCl2 on PCDFs formation weakened with the rising temperature since PCDFs destruction became dominant under higher temperature. Different from PCDFs, PCDDs concentration in treated soil and off gas decreased continuously with the increasing temperature.

  18. Apparatus for low temperature thermal desorption spectroscopy of portable samples

    Science.gov (United States)

    Stuckenholz, S.; Büchner, C.; Ronneburg, H.; Thielsch, G.; Heyde, M.; Freund, H.-J.

    2016-04-01

    An experimental setup for low temperature thermal desorption spectroscopy (TDS) integrated in an ultrahigh vacuum-chamber housing a high-end scanning probe microscope for comprehensive multi-tool surface science analysis is described. This setup enables the characterization with TDS at low temperatures (T > 22 K) of portable sample designs, as is the case for scanning probe optimized setups or high-throughput experiments. This combination of techniques allows a direct correlation between surface morphology, local spectroscopy, and reactivity of model catalysts. The performance of the multi-tool setup is illustrated by measurements of a model catalyst. TDS of CO from Mo(001) and from Mo(001) supported MgO thin films were carried out and combined with scanning tunneling microscopy measurements.

  19. Study of Thermal Desorption of Helium from Hydrogenated Zirconium

    Institute of Scientific and Technical Information of China (English)

    SUN Wei-Ming; WEI Yu-Cheng; SHI Li-Qun

    2006-01-01

    @@ A new method prepared for helium and hydrogen co-containing Zr films is presented to simulate aging metal tritides, in which direct current magnetron sputtering with a He/H/Ar mixture is used. The retained amount and depth profiles of helium and hydrogen are determined by elastic recoil detection analysis. Thermal desorption spectrometry is applied to investigate He thermal release and the effect of hydrogen. It is found that the hightemperature peaks with a large mount of helium release obviously shifted toward lower temperature at high hydrogen concentration, especially at the hydride transformation region, and that the shapes of the release peaks also changed due to the additional hydrogen. However, at the low-temperature releasing region the peak intense decreases when phase transformation takes place. The mechanism of helium thermal release and the effect of hydrogen are also discussed.

  20. Orbital dynamics of a solar sail accelerated by thermal desorption of coatings

    CERN Document Server

    Ancona, Elena

    2016-01-01

    In this study we considered a solar sail coated with materials that undergo thermal desorption at a specific temperature, as a result of heating by solar radiation at a particular heliocentric distance. Three different scenarios, that only differ in the way the sail approaches the Sun, were analyzed and compared. In every case once the perihelion is reached, the sail coat undergoes thermal desorption. When the desorption process ends, the sail then escapes the Solar System having the conventional acceleration due to solar radiation pressure. Thermal desorption here comes as an additional source of solar sail acceleration beside traditional propulsion systems for extrasolar space exploration. The compared scenarios are the following: i. Hohmann transfer plus thermal desorption. In this scenario the sail would be carried as a payload to the perihelion with a conventional propulsion system by an Hohmann transfer from Earth's orbit to an orbit very close to the Sun (almost at 0.1 AU) and then be deployed there. i...

  1. Orbital dynamics of a solar sail accelerated by thermal desorption of coatings

    OpenAIRE

    2016-01-01

    In this study we considered a solar sail coated with materials that undergo thermal desorption at a specific temperature, as a result of heating by solar radiation at a particular heliocentric distance. Three different scenarios, that only differ in the way the sail approaches the Sun, were analyzed and compared. In every case once the perihelion is reached, the sail coat undergoes thermal desorption. When the desorption process ends, the sail then escapes the Solar System having the conventi...

  2. Creation of electron-positron plasma with superstrong laser field

    CERN Document Server

    Narozhny, N B

    2013-01-01

    We present a short review of recent progress in studying QED effects of interaction of ultra-relativistic laser pulses with vacuum and $e^-e^+$ plasma. The development of laser technologies promises very rapid growth of laser intensities in close future already. Two exawatt class facilities (ELI and XCELS, Russia) in Europe are already in the planning stage. Realization of these projects will make available a laser of intensity $\\sim 10^{26}$W/cm$^2$ or even higher. Therefore, discussion of nonlinear optical effects in vacuum are becoming urgent for experimentalists and are currently gaining much attention. We show that, in spite of the fact that the respective field strength is still essentially less than $E_S=m^2c^3/e\\hbar=1.32\\cdot 10^{16}$V/cm, the nonlinear vacuum effects will be accessible for observation at ELI and XCELS facilities. The most promissory for observation is the effect of pair creation by laser pulse in vacuum. It is shown, that at intensities $\\sim 5\\cdot 10^{25}$W/cm$^2$, creation even o...

  3. Treating high-mercury-containing lamps using full-scale thermal desorption technology.

    Science.gov (United States)

    Chang, T C; You, S J; Yu, B S; Chen, C M; Chiu, Y C

    2009-03-15

    The mercury content in high-mercury-containing lamps are always between 400 mg/kg and 200,000 mg/kg. This concentration is much higher than the 260 mg/kg lower boundary recommended for the thermal desorption process suggested by the US Resource Conservation and Recovery Act. According to a Taiwan EPA survey, about 4,833,000 cold cathode fluorescent lamps (CCFLs), 486,000 ultraviolet lamps and 25,000 super high pressure mercury lamps (SHPs) have been disposed of in the industrial waste treatment system, producing 80, 92 and 9 kg-mercury/year through domestic treatment, offshore treatment and air emissions, respectively. To deal with this problem we set up a full-scale thermal desorption process to treat and recover the mercury from SHPs, fluorescent tube tailpipes, fluorescent tubes containing mercury-fluorescent powder, and CCFLs containing mercury-fluorescent powder and monitor the use of different pre-heating temperatures and desorption times. The experimental results reveal that the average thermal desorption efficiency of SHPs and fluorescent tube tailpipe were both 99.95%, while the average thermal desorption efficiencies of fluorescent tubes containing mercury-fluorescent powder were between 97% and 99%. In addition, a thermal desorption efficiency of only 69.37-93.39% was obtained after treating the CCFLs containing mercury-fluorescent powder. These differences in thermal desorption efficiency might be due to the complexity of the mercury compounds contained in the lamps. In general, the thermal desorption efficiency of lamps containing mercury-complex compounds increased with higher temperatures.

  4. Present status of thin oxide films creation in a microwave plasma

    Energy Technology Data Exchange (ETDEWEB)

    Loncar, G. (Ceske Vysoke Uceni Technicke, Prague (Czechoslovakia). Fakulta Jaderna a Fysikalne Inzenyrska); Musil, J.; Bardos, L. (Ceskoslovenska Akademie Ved, Prague. Ustav Fyziky Plazmatu)

    1980-01-01

    The paper summarizes present knowledge of the creation of thin films in both isotropic and magnetoactive plasmas. It analyses conditions under which films in the microwave plasma can be created and shows how the growth rates and properties of films depend on microparameters of the plasma. On the basis of plasma floating potential measurements it is shown why the creation of thin films in microwave discharges takes place at high electron plasma densities (N > or approximately 10/sup 12/ cm/sup -3/) only. Besides, it describes properties of formed films, underlines the negative role of fast electrons in forming good quality films and gives recommendation of how to avoid their generation. Considerable attention is devoted also to a comparison of film creation in pulsed and continuous plasmas. The possibility of film creation at low temperatures by the deposition technique utilizing microwave excitation of molecular gases is given.

  5. ECO LOGIC INTERNATIONAL GAS-PHASE CHEMICAL REDUCTION PROCESS - THE THERMAL DESORPTION UNIT - APPLICATIONS ANALYSIS REPORT

    Science.gov (United States)

    ELI ECO Logic International, Inc.'s Thermal Desorption Unit (TDU) is specifically designed for use with Eco Logic's Gas Phase Chemical Reduction Process. The technology uses an externally heated bath of molten tin in a hydrogen atmosphere to desorb hazardous organic compounds fro...

  6. Offline thermal-desorption proton-transfer-reaction mass spectrometry to study composition of organic aerosol

    NARCIS (Netherlands)

    Timkovsky, J.; Dusek, U.; Henzing, J. S.; Kuipers, T. L.; Röckmann, T.; Holzinger, R.

    2015-01-01

    We present a novel approach to study the organic composition of aerosol filter samples using thermal-desorption proton-transfer-reaction mass spectrometry (TD-PTR-MS) in the laboratory. The method is tested and validated based on the comparison with in situ TD-PTR-MS measurements. In general, we obs

  7. Thermal desorption of deuterium from modified carbon nanotubes and its correlation to the microstructure

    NARCIS (Netherlands)

    Lisowski, W.; Keim, E.G.; Berg, van den A.H.J.; Smithers, M.A.

    2006-01-01

    The process of deuterium desorption from single-wall carbon nanotubes (SWNTs) modified by atomic (D) and molecular (D2) deuterium treatment was investigated in an ultrahigh vacuum environment using thermal desorption mass spectroscopy (TDMS). Microstructural and chemical analyses of SWNT material, m

  8. Decomposition of thin titanium deuteride films; thermal desorption kinetics studies combined with microstructure analysis

    NARCIS (Netherlands)

    Lisowski, Wojciech; Keim, Enrico G.; Kaszkur, Zbigniew; Smithers, Mark A.

    2008-01-01

    The thermal evolution of deuterium from thin titanium films, prepared under UHV conditions and deuterated in situ at room temperature, has been studied by means of thermal desorption mass spectrometry (TDMS) and a combination of scanning electron microscopy (SEM), transmission electron microscopy (T

  9. Thermal desorption from surfaces with laser-induced defects

    Energy Technology Data Exchange (ETDEWEB)

    Szabelski, Pawel; Panczyk, Tomasz; Rudzinski, Wladyslaw

    2002-12-30

    Monte Carlo simulation method was used to mimic surface damage development caused by short laser pulses. The influence of pulsed laser irradiation on the creation of defect concentration was examined in the case of a model surface. In particular, the dependence of the intact surface area on a number of laser scans was studied and compared with the experimental results obtained for Rh(1 1 1) crystal face. Changes in the adsorptivoperties of the surface produced by laser irradiation are explained with the help of a simple geometric model connecting the laser intensity and the disordered area generated by a single laser shot. It was demonstrated that exponential decay of the Low Energy Electron Diffraction (LEED) signal with the number of laser scans, which is observed experimentally, may result directly from the overlapping of the laser spots created on the surface. This effect becomes enhanced when the laser intensity, hence the spot size, increases. The importance of laser-induced defects in the kinetics of catalytic/separation processes was examined in the case of temperature programmed desorption (TPD) spectra from surfaces subjected to a different number of laser shots. The spectra were simulated by employing the Monte Carlo method as well as by application of the absolute rate theory (ART) coupled with the mean field approximation. The results obtained with both methods were in a good agreement even when weak lateral interactions in the adsorbed phase were allowed.

  10. Creation of an Ultracold Plasma by Photoionizing Laser-Cooled Cesium Atom

    Institute of Scientific and Technical Information of China (English)

    JING Qun; FENG Zhi-Gang; ZHANG Lin-Jie; LI Chang-Yong; ZHAO Jian-Ming; JIA Suo-Tang

    2008-01-01

    @@ The signals of ultracold plasma are observed by two-photon ionization of laser-cooled atom in a caesium magneto-optical trap.A simple model has been introduced to explain the creation of plasma, and the mechanism is further investigated by changing the energy of a pulsed dye laser and the number of initial cooled atoms.

  11. Bonding configurations for nickelocene on Ag(100) and steric effects in thermal desorption

    Energy Technology Data Exchange (ETDEWEB)

    Borca, C.N.; Welipitiya, D.; Dowben, P.A.; Boag, N.M.

    2000-02-10

    The molecular adsorption and desorption of nickelocene, Ni(C{sub 5}H{sub 5}){sub 2}, on Ag(100) has been studied by coverage dependent angle-resolved thermal desorption. The angle-resolved thermal desorption of nickelocene is unusual in that the molecular orientation is seen to affect the angular dependence of molecular desorption. The coexistence of two chemisorption phases for molecular nickelocene adsorption on Ag(100) near the desorption temperature of approximately 230 K is identified. One phase, with the bonding configuration of the nickelocene molecular axis along the surface normal, appears to dominate at higher coverages. The results are discussed in the context of rehybridization and recent angle-resolved photoemission and high-resolution electron energy loss measurements.

  12. Decomposition kinetics study of zirconium hydride by interrupted thermal desorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Mingwang; Liang, Li; Tang, Binghua; Xiang, Wei; Wang, Yuan; Cheng, Yanlin; Tan, Xiaohua, E-mail: caepiee@163.com

    2015-10-05

    Highlights: • Interrupted TDS was applied to investigate the mechanism of ZrH{sub 2} decomposition. • The activation energies for the five desorption peaks were determined. • The origins of the five desorption peaks were identified. • The γZrH phase was observed at ambient conditions. - Abstract: Thermal desorption kinetics of zirconium hydride powder were studied using thermogravimetry and simultaneous thermal desorption spectroscopy. The activation energies for observed desorption peaks were estimated according to Kissinger relation. The intermediate phase composition was studied using X-ray diffraction by rapid cooling on different stages of heating. The origins of the peaks were described as the equilibrium hydrogen pressure of a number of consecutive phase regions that decomposition reaction passed through. The zirconium monohydride γZrH was observed for extended periods of time at ambient conditions, which has been supposed to be metastable for a long time.

  13. Adsorption, Diffusion and Thermal Desorption Features of Cyclopentane and Cyclohexane in Silicalite-1

    Institute of Scientific and Technical Information of China (English)

    DUAN, Lin-Hai; SONG, Li-Juan; ZHANG, Xiao-Tong; TANG, Ke; DAI, Zhen-Hua; SUN, Zhao-Lin

    2006-01-01

    Adsorption, diffusion and thermal desorption features of cyclopentane and cyclohexane in silicalite-1 have been investigated using the intelligent gravimetric technique. Both the saturation adsorption loadings and diffusion coefficient of cyclopentane were greater than those of cyclohexane. The diffusivity of cyclopentane was about one order of magnitude greater than that of cyclohexane at the same temperature and initial loading. For cyclopentane, there was only one kind of desorption process at adsorption loadings lower than 4 muc (molecule per unit cell), but two desorption processes appeared at the adsorption loadings higher than 4 muc. While for cyclohexane, one desorption process was found in the whole range of loadings. Both thermal desorption peaks of cyclopentane and cyclohexane moved to higher temperature region with increasing loading.

  14. Modelling of hydrogen thermal desorption spectrum in nonlinear dynamical boundary-value problem

    Science.gov (United States)

    Kostikova, E. K.; Zaika, Yu V.

    2016-11-01

    One of the technological challenges for hydrogen materials science (including the ITER project) is the currently active search for structural materials with various potential applications that will have predetermined limits of hydrogen permeability. One of the experimental methods is thermal desorption spectrometry (TDS). A hydrogen-saturated sample is degassed under vacuum and monotone heating. The desorption flux is measured by mass spectrometer to determine the character of interactions of hydrogen isotopes with the solid. We are interested in such transfer parameters as the coefficients of diffusion, dissolution, desorption. The paper presents a distributed boundary-value problem of thermal desorption and a numerical method for TDS spectrum simulation, where only integration of a nonlinear system of low order (compared with, e.g., the method of lines) ordinary differential equations (ODE) is required. This work is supported by the Russian Foundation for Basic Research (project 15-01-00744).

  15. Organic and inorganic decomposition products from the thermal desorption of atmospheric particles

    OpenAIRE

    Williams, Brent J.; Zhang, Yaping; Zuo, Xiaochen; Martinez, Raul E.; Walker, Michael J.; Kreisberg, Nathan M.; Goldstein, Allen H.; Docherty, Kenneth S.; Jimenez, Jose L.

    2016-01-01

    Atmospheric aerosol composition is often analyzed using thermal desorption techniques to evaporate samples and deliver organic or inorganic molecules to various designs of detectors for identification and quantification. The organic aerosol (OA) fraction is composed of thousands of individual compounds, some with nitrogen- and sulfur-containing functionality and, often contains oligomeric material, much of which may be susceptible to decomposition upon heating. Here we analy...

  16. Organic and inorganic decomposition products from the thermal desorption of atmospheric particles

    OpenAIRE

    B. J. Williams; Y. Zhang; X. Zuo; R. E. Martinez; Walker, M. J.; N. M. Kreisberg; Goldstein, A. H.; K. S. Docherty; Jimenez, J.L.

    2015-01-01

    Atmospheric aerosol composition is often analyzed using thermal desorption techniques to evaporate samples and deliver organic or inorganic molecules to various designs of detectors for identification and quantification. The organic aerosol (OA) fraction is composed of thousands of individual compounds, some with nitrogen- and sulfur-containing functionality, and often contains oligomeric material, much of which may be susceptible to decomposition upon heating. Here we analy...

  17. PCDD/F formation during thermal desorption of p,p'-DDT contaminated soil.

    Science.gov (United States)

    Zhao, Zhonghua; Ni, Mingjiang; Li, Xiaodong; Buekens, Alfons; Yan, Jianhua

    2017-05-01

    Thermal treatment of polychlorinated biphenyls (PCB) contaminated soil was shown in earlier work to generate polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF). In this study, the PCDD/F were studied arising during the remediation of p,p'-DDT contaminated soil by thermal desorption. Three kinds of soil (sandy, clayey and lateritic soil) were tested to investigate the effect of soil texture on PCDD/F formation. Those soils were artificially polluted with p,p'-DDT, obtaining a concentration level of 100 mg/kg. Thermal desorption experiments were conducted for 10 min at 300 °C in an air atmosphere. The total concentration of PCDD/F generated for three soils were 331, 803 and 865 ng/kg, respectively, and TeCDD and TeCDF were dominant among all PCDD/F congeners. After thermal desorption, the total amount of PCDD/F generated both in soil and in off-gas correlated positively with the amount of DDT added to soil. In addition, a possible pathway of the formation of PCDD/F was presented.

  18. Progress toward the creation of magnetically confined pair plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Saitoh, Haruhiko [Max-Planck-Institut fuer Plasmaphysik (Germany); The University of Tokyo (Japan); Hergenhahn, Uwe; Paschkowski, Norbert; Stanja, Juliane; Stenson, Eve V. [Max-Planck-Institut fuer Plasmaphysik (Germany); Niemann, Holger; Sunn Pedersen, Thomas [Max-Planck-Institut fuer Plasmaphysik (Germany); Ernst-Moritz-Arndt-Universitaet Greifswald (Germany); Stoneking, Matthew R. [Max-Planck-Institut fuer Plasmaphysik (Germany); Lawrence University (United States); Hugenschmidt, Christoph; Piochacz, Christian; Vohburger, Sebastian [Technische Universitaet Muenchen (Germany); Schweikhard, Lutz [Ernst-Moritz-Arndt-Universitaet Greifswald (Germany); Danielson, James R.; Surko, Clifford M. [University of California, San Diego (United States)

    2016-07-01

    The PAX (Positron Accumulation eXperiment) and APEX (A Positron Electron eXperiment) projects aim to experimentally study the unique wave propagation and stability properties of pair plasmas. We plan to accumulate a large number of positrons in a multicell-type trap system (PAX) and to confine them with electrons in APEX, a levitated dipole or stellarator configuration, operated at the NEPOMUC facility, the world's most intense positron source. In this contribution, we report on recent results from PAX and APEX. We have conducted electron experiments with a 2.3 T Penning-Malmberg trap; confinement for more than 1 hour and observation of a collective mode were demonstrated. At NEPOMUC, we have characterized the positron beam for a wide energy range. In a prototype permanent-magnet dipole trap, efficient (38%) injection of the remoderated 5 eV positron beam was realized using E x B drifts. Based on these results, design studies on the confinement of pair-plasmas in a levitated dipole trap are ongoing.

  19. Organic and inorganic decomposition products from the thermal desorption of atmospheric particles

    Science.gov (United States)

    Williams, Brent J.; Zhang, Yaping; Zuo, Xiaochen; Martinez, Raul E.; Walker, Michael J.; Kreisberg, Nathan M.; Goldstein, Allen H.; Docherty, Kenneth S.; Jimenez, Jose L.

    2016-04-01

    Atmospheric aerosol composition is often analyzed using thermal desorption techniques to evaporate samples and deliver organic or inorganic molecules to various designs of detectors for identification and quantification. The organic aerosol (OA) fraction is composed of thousands of individual compounds, some with nitrogen- and sulfur-containing functionality and, often contains oligomeric material, much of which may be susceptible to decomposition upon heating. Here we analyze thermal decomposition products as measured by a thermal desorption aerosol gas chromatograph (TAG) capable of separating thermal decomposition products from thermally stable molecules. The TAG impacts particles onto a collection and thermal desorption (CTD) cell, and upon completion of sample collection, heats and transfers the sample in a helium flow up to 310 °C. Desorbed molecules are refocused at the head of a gas chromatography column that is held at 45 °C and any volatile decomposition products pass directly through the column and into an electron impact quadrupole mass spectrometer. Analysis of the sample introduction (thermal decomposition) period reveals contributions of NO+ (m/z 30), NO2+ (m/z 46), SO+ (m/z 48), and SO2+ (m/z 64), derived from either inorganic or organic particle-phase nitrate and sulfate. CO2+ (m/z 44) makes up a major component of the decomposition signal, along with smaller contributions from other organic components that vary with the type of aerosol contributing to the signal (e.g., m/z 53, 82 observed here for isoprene-derived secondary OA). All of these ions are important for ambient aerosol analyzed with the aerosol mass spectrometer (AMS), suggesting similarity of the thermal desorption processes in both instruments. Ambient observations of these decomposition products compared to organic, nitrate, and sulfate mass concentrations measured by an AMS reveal good correlation, with improved correlations for OA when compared to the AMS oxygenated OA (OOA

  20. Reliability of a BTEX radial diffusive sampler for thermal desorption: field measurements

    Science.gov (United States)

    Bruno, P.; Caputi, M.; Caselli, M.; de Gennaro, G.; de Rienzo, M.

    Radiello ®, a radial symmetry diffusive sampler, has been evaluated for its potential for ambient air quality monitoring, in particular for benzene, toluene, ethyl benzene, p-xylene, m-xylene, o-xylene (BTEX) measurements. BTEX were first sampled onto adsorbing cartridges before analyses were performed by thermal desorption and GC-MS. Tests were carried out to determine blank values and any storage effects. The results of an investigation into repeatability of the Radiello ® sampler and the influence of sampling time under field conditions are reported. Inter-comparison with automatic instruments is also illustrated.

  1. Layer resolved spectroscopy of potassium adsorbed on a Ru(001) surface: Photoemission and thermal desorption study

    Energy Technology Data Exchange (ETDEWEB)

    Hrbek, J. (Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973 (US)); Shek, M. (Department of Physics, Hunter College of CUNY, New York, New York 10021); Sham, T.K. (Department of Chemistry, University of Western Ontario, London, Ontario N6A 5B7, Canada); Xu, G. (Chemistry Department, Brookhaven National Laboratory, Upton, New York, 11973)

    1989-11-01

    High-resolution photoemission spectroscopy and thermal desorption were used to study the coverage dependence of the K 3{ital p}{sub 3/2,1/2} core levels of K overlayers on Ru(001). Three doublets were observed to evolve sequentially and to shift to higher binding energy with increasing coverage of potassium. The doublets were assigned to photoemission from the interface (first layer), bulk'' (second layer), and surface (third layer). Spin--orbit splitting was observed for the first time in the condensed potassium phase by photoemission. The results are discussed in terms of the equivalent core approximation using a Born--Haber cycle. In the thermal desorption data three coverage regimes can be distinguished: a first layer desorbing with first-order kinetics and a strongly decreasing heat of adsorption ({ital E}{sub {ital A}} =2.80--0.87 eV); a second layer with zero-order desorption kinetics and {ital E}{sub {ital A}} =0.78 eV; a third layer and multilayers with the same kinetic order but with {ital E}{sub {ital A}} increasing from 0.78 to 0.93 eV, which is close to the heat of sublimation of potassium.

  2. Application of thermal desorption for the identification of mercury species in solids derived from coal utilization.

    Science.gov (United States)

    Rumayor, M; Diaz-Somoano, M; Lopez-Anton, M A; Martinez-Tarazona, M R

    2015-01-01

    The speciation of mercury is currently attracting widespread interest because the emission, transport, deposition and behaviour of toxic mercury species depend on its chemical form. The identification of these species in low concentrations is no easy task and it is even more complex in coal combustion products due to the fact that these products contain organic and mineral matter that give rise to broad peaks and make it difficult to carry out qualitative and quantitative analysis. In this work, a solution to this problem is proposed using a method based on thermal desorption. A sequential extraction procedure was employed for the comparison and validation of the method developed. Samples of fly ashes and soils were analyzed by both of these methods, and thermal desorption was found to be an appropriate technique for mercury speciation. Even in the case of low mercury contents, recovery percentages were close to 100%. The main mercury species identified in the samples studied were HgS and, to a lesser extent, HgO and HgSO4. In addition, although the presence of mercury complexes cannot be demonstrated, the desorption behaviour and sequential extraction results suggest that this element might be associated with the mineral matrix or with carbon particles in some of the solids. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Thermal desorption characterisation of molecularly imprinted polymers. Part I: A novel study using direct-probe GC-MS analysis.

    Science.gov (United States)

    Cummins, Wayne; Duggan, Patrick; McLoughlin, Peter

    2008-06-01

    A novel thermal desorption technique using a direct-probe device (Chromatoprobe) attached to a gas chromatograph-mass spectrometer is presented for the thermal pretreatment, characterisation and analysis of molecularly imprinted polymers. The technique is demonstrated as effective for the removal of volatile materials, including template and unreacted monomers, from methacrylic acid-ethylene glycol dimethacrylate copolymers imprinted with 2-aminopyridine. Mass spectrometry is a powerful technique for polymer bleed characterisation. Thermal desorption studies on reloaded template and related compounds are reported as a means of assessing polymer morphology, specific binding by imprinted polymers compared with reference non-imprinted polymers and selective binding by an imprinted polymer for its template. Calibration studies on the thermal desorption technique using an internal standard are presented with R(2) > 0.999. The technique provides a novel method for assessment of polymer thermal stability, composition and morphology.

  4. Charge creation and nucleation of longitudinal plasma wave in coupled Josephson junctions

    OpenAIRE

    Shukrinov, Yu M.; Hamdipour, M.

    2009-01-01

    We study the phase dynamics in coupled Josephson junctions describing by system of nonlinear differential equations. Results of detailed numerical simulations of charge creation in the superconducting layers and the longitudinal plasma wave (LPW) nucleation are presented. We demonstrate the different time stages in the development of the LPW and present results of FFT analysis at different values of bias current. The correspondence between the breakpoint position on the outermost branch of cu...

  5. Multivariate analysis of progressive thermal desorption coupled gas chromatography-mass spectrometry.

    Energy Technology Data Exchange (ETDEWEB)

    Van Benthem, Mark Hilary; Mowry, Curtis Dale; Kotula, Paul Gabriel; Borek, Theodore Thaddeus, III

    2010-09-01

    Thermal decomposition of poly dimethyl siloxane compounds, Sylgard{reg_sign} 184 and 186, were examined using thermal desorption coupled gas chromatography-mass spectrometry (TD/GC-MS) and multivariate analysis. This work describes a method of producing multiway data using a stepped thermal desorption. The technique involves sequentially heating a sample of the material of interest with subsequent analysis in a commercial GC/MS system. The decomposition chromatograms were analyzed using multivariate analysis tools including principal component analysis (PCA), factor rotation employing the varimax criterion, and multivariate curve resolution. The results of the analysis show seven components related to offgassing of various fractions of siloxanes that vary as a function of temperature. Thermal desorption coupled with gas chromatography-mass spectrometry (TD/GC-MS) is a powerful analytical technique for analyzing chemical mixtures. It has great potential in numerous analytic areas including materials analysis, sports medicine, in the detection of designer drugs; and biological research for metabolomics. Data analysis is complicated, far from automated and can result in high false positive or false negative rates. We have demonstrated a step-wise TD/GC-MS technique that removes more volatile compounds from a sample before extracting the less volatile compounds. This creates an additional dimension of separation before the GC column, while simultaneously generating three-way data. Sandia's proven multivariate analysis methods, when applied to these data, have several advantages over current commercial options. It also has demonstrated potential for success in finding and enabling identification of trace compounds. Several challenges remain, however, including understanding the sources of noise in the data, outlier detection, improving the data pretreatment and analysis methods, developing a software tool for ease of use by the chemist, and demonstrating our belief

  6. Hydrogen solubility and diffusion in austenitic stainless steels studied with thermal desorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Yagodzinskyy, Y.; Todoshchenko, O.; Papula, S.; Haenninen, H. [Laboratory of Engineering Materials, School of Science and Technology, Aalto University, Espoo (Finland)

    2011-01-15

    Hydrogen solubility and diffusion in austenitic stainless steels, namely AISI 310, AISI 301LN and AISI 201, are studied with thermal desorption spectroscopy (TDS) after electrochemical potentiostatic hydrogen pre-charging. Temperature dependencies of hydrogen desorption for all studied steels manifest a complex main peak caused by hydrogen releasing from the steel lattice by diffusion. Depending on the steel and heating rate the peak is situated from 350 to 500 K and its shape reflects a specific of hydrogen diffusion in stainless steels, which are multicomponent alloys. Analysis of the TDS curves is based on the hydrogen diffusion model taking into account trapping of hydrogen atoms in the energetically deep interstitial positions in the steel crystal lattice. Diffusion coefficient of hydrogen and its total content after the same charging procedure are obtained from the TDS curves and compared for the studied steels. (Copyright copyright 2011 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. A Solid Trap and Thermal Desorption System with Application to a Medical Electronic Nose

    Directory of Open Access Journals (Sweden)

    Xuntao Xu

    2008-11-01

    Full Text Available In this paper, a solid trap/thermal desorption-based odorant gas condensation system has been designed and implemented for measuring low concentration odorant gas. The technique was successfully applied to a medical electronic nose system. The developed system consists of a flow control unit, a temperature control unit and a sorbent tube. The theoretical analysis and experimental results indicate that gas condensation, together with the medical electronic nose system can significantly reduce the detection limit of the nose system and increase the system’s ability to distinguish low concentration gas samples. In addition, the integrated system can remove the influence of background components and fluctuation of operational environment. Even with strong disturbances such as water vapour and ethanol gas, the developed system can classify the test samples accurately.

  8. Thermal desorption from self-damaged tungsten exposed to deuterium atoms

    Energy Technology Data Exchange (ETDEWEB)

    Gasparyan, Yu.M., E-mail: gasparyan.yury@plasma.mephi.ru [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoe sh.31, 115409 Moscow (Russian Federation); Ogorodnikova, O.V. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoe sh.31, 115409 Moscow (Russian Federation); Max-Planck-Institut für Plasmaphysik, EURATOM Association, Boltzmannstr. 2, D-85748 Garching (Germany); Efimov, V.S.; Mednikov, A.; Marenkov, E.D.; Pisarev, A.A. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoe sh.31, 115409 Moscow (Russian Federation); Markelj, S.; Čadež, I. [Jožef Stefan Institute and Association EURATOM-MHEST, Jamova Cesta 39, 1000 Ljubljana (Slovenia)

    2015-08-15

    Deuterium retention in tungsten damaged by 2–20 MeV W ions and then exposed to D atoms was investigated by means of thermal desorption spectroscopy. Experimental data demonstrate a significant increase of deuterium retention in the presence of radiation defects. A remarkable amount of deuterium is trapped even at the temperature of 800 K. TDS spectra were simulated using the computer code DIFTRAP based on kinetic rate equations to derive parameters of deuterium interaction with radiation defects. It was shown that irradiation by MeV W ions forms in W a high concentration of strong traps with the detrapping energy of 1.7–2 eV. These traps play major role in the D retention at elevated temperatures. The experimental spectra have peculiarities that are not described by the standard modeling; and the reasons for that are discussed.

  9. Activation energy of thermal desorption of silicon oxide layers on silicon substrates

    Science.gov (United States)

    Enta, Yoshiharu; Osanai, Shodai; Ogasawara, Takahito

    2017-02-01

    Thermal desorption rates of silicon oxide layers, from 20 to 120 nm in thickness, on silicon substrates in vacuum have been accurately obtained from intervals between ring structures formed inside voids on the oxide layers. From the temperature dependence of the desorption rate, the activation energy and frequency factor of the desorption reaction have been derived as a function of the oxide thickness. The obtained values are compared with the previous studies, and as a result, the activation energy is found to be almost constant ( 4 eV) in a wide range of the oxide thickness. The frequency factor decreases as the inverse square of the oxide thickness. The decomposition kinetics of the oxide layer is also discussed from the obtained results.

  10. Non-isothermal kinetics of the thermal desorption of mercury from a contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, F. A.; Sierra, M. J.; Rodriguez, O.; Millan, R.; Alguacil, F. J.

    2014-04-01

    The Almaden mining district (Ciudad Real, Spain) was the largest cinnabar (mercury sulphide) mine in the world. Its soils have high levels of mercury a consequence of its natural lithology, but often made much worse by its mining history. The present work examines the thermal desorption of two contaminated soils from the Almaden area under non-isothermal conditions in a N{sub 2} atmosphere, using differential scanning calorimetry (DSC). DSC was performed at different heating rates between room temperature and 600 degree centigrade. Desorption temperatures for different mercury species were determined. The Friedman, Flynn-Wall-Ozawa and Coasts Redfern methods were employed to determine the reaction kinetics from the DSC data. The activation energy and pre-exponential factor for mercury desorption were calculated. (Author)

  11. Detection of deuterium trapping sites in tungsten by thermal desorption spectroscopy and positron annihilation spectroscopy

    Directory of Open Access Journals (Sweden)

    K. Sato

    2016-12-01

    Full Text Available Thermal desorption spectroscopy (TDS of tungsten implanted with D2+ ions was performed after irradiation with 8 MeV-electrons, 5.0keV-D2+, and 6.0 MeV-Fe3+. The release peak temperatures of the TDS spectra are discussed. Positron annihilation lifetime (PAL measurements of electron-irradiated tungsten were also performed, showing that single vacancies migrate a sufficient distance to arrive at a sink or meet interstitial-type defects during annealing at 673K. A decrease in the PAL was detected for single vacancies that contain deuterium atoms. The peak temperature of deuterium release from dislocations was lower than that from single vacancies. In samples irradiated with 6.0 MeV-Fe3+, the effect of Fe contamination on deuterium trapping and the deuterium release from voids were detected. These tendencies correspond to previous works.

  12. MGP remediation using thermal desorption: emerging technology yields a permanent solution

    Energy Technology Data Exchange (ETDEWEB)

    Umfleet, D.E.; Bachman, S.A.; Highland, E. [Barr Engineering Company, Ann Arbor, MI (United States)

    1997-12-01

    An investigation of a former manufactured gas plant (MGP) at the site for Northwestern Public Service`s new operations buildings uncovered evidence of MGP residuals in the moist, clay-rich soils. On site-thermal desorption was selected as the remedial method. A low-temperature, counter-flow, direct-fired rotary desorber heats soils up to 1200{degree}F to volatilize organic fractions. Soils containing polyaromatic hydrocarbon (PAH) compounds were excavated, treated effectively, and reused at the site as backfill. For the approximately 47,000 tons of soil processed, remediation costs were 82 dollars per ton. Site-specific factors affecting project costs included the volume of soil treated, soil type and condition, inclement weather, and market conditions. Soils were treated to below state-approved performance criterion, and remediation of the site was completed just 18 months after the project began. 1 fig., 2 tabs.

  13. Analysis of organic contaminants from silicon wafer and disk surfaces by thermal desorption-GC-MS

    Science.gov (United States)

    Camenzind, Mark J.; Ahmed, Latif; Kumar, Anurag

    1999-03-01

    Organic contaminants can affect semiconductor wafer processing including gate oxide integrity, polysilicon growth, deep ultraviolet photoresist line-width, and cleaning & etching steps. Organophosphates are known to counter dope silicon wafers. Organic contaminants in disk drives can cause failures due to stiction or buildup on the heads. Therefore, it is important to identify organic contaminants adsorbed on wafer or disk surfaces and find their sources so they can be either completely eliminated or at least controlled. Dynamic headspace TD-GC-MS (Thermal Desorption-Gas Chromatography-Mass Spectrometry) methods are very sensitive and can be used to identify organic contaminants on disks and wafers, in air, or outgassing from running drives or their individual components.

  14. Quantification of Selected Vapour-Phase Compounds using Thermal Desorption-Gas Chromatography

    Directory of Open Access Journals (Sweden)

    McLaughlin DWJ

    2014-12-01

    Full Text Available A robust method for the analysis of selected vapour phase (VP compounds in mainstream smoke (MSS is described. Cigarettes are smoked on a rotary smoking machine and the VP that passes through the Cambridge filter pad collected in a TedlarA¯ bag. On completion of smoking, the bag contents are sampled onto an adsorption tube containing a mixed carbon bed. The tube is subsequently analysed on an automated thermal desorption (TD system coupled to a gas chromatography-flame ionization detector (GC-FID using a PoraPLOT-Q column. Quantification of 14 volatile compounds including the major carbonyls is achieved. Details of the method validation data are included in this paper. This method has been used to analyse the VP of cigarette MSS over a wide range of ‘tar’ deliveries and configurations with excellent repeatability. Results for the University of Kentucky reference cigarette 1R4F are in good agreement with reported values.

  15. DEMONSTRATION BULLETIN: THE ECO LOGIC THERMAL DESORPTION UNIT - MIDDLEGROUND LANDFILL - BAY CITY, MI - ELI ECO LOGIC INTERNATIONAL, INC.

    Science.gov (United States)

    ECO Logic has developed a thermal desorption unit 0"DU) for the treatment of soils contaminated with hazardous organic contaminants. This TDU has been designed to be used in conjunction with Eco Logic's patented gas-phase chemical reduction reactor. The Eco Logic reactor is the s...

  16. DEMONSTRATION BULLETIN: THE ECO LOGIC THERMAL DESORPTION UNIT - MIDDLEGROUND LANDFILL - BAY CITY, MI - ELI ECO LOGIC INTERNATIONAL, INC.

    Science.gov (United States)

    ECO Logic has developed a thermal desorption unit 0"DU) for the treatment of soils contaminated with hazardous organic contaminants. This TDU has been designed to be used in conjunction with Eco Logic's patented gas-phase chemical reduction reactor. The Eco Logic reactor is the s...

  17. Characterisation of Dissolved Organic Carbon by Thermal Desorption - Proton Transfer Reaction - Mass Spectrometry

    Science.gov (United States)

    Materić, Dušan; Peacock, Mike; Kent, Matthew; Cook, Sarah; Gauci, Vincent; Röckmann, Thomas; Holzinger, Rupert

    2017-04-01

    Dissolved organic carbon (DOC) is an integral component of the global carbon cycle. DOC represents an important terrestrial carbon loss as it is broken down both biologically and photochemically, resulting in the release of carbon dioxide (CO2) to the atmosphere. The magnitude of this carbon loss can be affected by land management (e.g. drainage). Furthermore, DOC affects autotrophic and heterotrophic processes in aquatic ecosystems, and, when chlorinated during water treatment, can lead to the release of harmful trihalomethanes. Numerous methods have been used to characterise DOC. The most accessible of these use absorbance and fluorescence properties to make inferences about chemical composition, whilst high-performance size exclusion chromatography can be used to determine apparent molecular weight. XAD fractionation has been extensively used to separate out hydrophilic and hydrophobic components. Thermochemolysis or pyrolysis Gas Chromatography - Mass Spectrometry (GC-MS) give information on molecular properties of DOC, and 13C NMR spectroscopy can provide an insight into the degree of aromaticity. Proton Transfer Reaction - Mass Spectrometry (PTR-MS) is a sensitive, soft ionisation method suitable for qualitative and quantitative analysis of volatile and semi-volatile organic vapours. So far, PTR-MS has been used in various environmental applications such as real-time monitoring of volatile organic compounds (VOCs) emitted from natural and anthropogenic sources, chemical composition measurements of aerosols etc. However, as the method is not compatible with water, it has not been used for analysis of organic traces present in natural water samples. The aim of this work was to develop a method based on thermal desorption PTR-MS to analyse water samples in order to characterise chemical composition of dissolved organic carbon. We developed a clean low-pressure evaporation/sublimation system to remove water from samples and thermal desorption system to introduce

  18. GoAmazon 2014/15 Thermal Desorption Chemical Ionization Mass Spectrometer (TDCIMS) Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Smith, JN [Univ. of California, Irvine, CA (United States)

    2016-04-01

    The Thermal Desorption Chemical Ionization Mass Spectrometer (TDCIMS) deployment to the U.S. Department of Energy (DOE)’s Atmospheric Radiation Measurement (ARM) Climate Research Facility T3 site in Manacapuru, Brazil, was motivated by two main scientific objectives of the Green Ocean Amazon (GoAmazon) 2014/15 field campaign. 1) Study the interactions between anthropogenic and biogenic emissions by determining important molecular species in ambient nanoparticles. To address this, TDCIMS data will be combined with coincident measurements such as gas-phase sulfuric acid to determine the contribution of sulfuric acid condensation to nucleation and growth. We can then compare that result to TDCIMS-derived nanoparticle composition to determine the fraction of growth that can be attributed to the uptake of organic compounds. The molecular composition of sampled particles will also be used to attribute specific chemical species and mechanisms to growth, such as the condensation of low-volatility species or the oligomerization of α-dicarbonyl compounds. 2) Determine the source of new ambient nanoparticles in the Amazon. The hypothesis prior to measurements was that potassium salts formed from the evaporation of primary particles emitted by fungal spores can provide a unique and important pathway for new particle production in the Amazon basin. To explore this hypothesis, the TDCIMS recorded the mass spectra of sampled ambient particles using a protonated water cluster Chemical Ionization Mass Spectrometer (CIMS). Laboratory tests performed using potassium salts show that the TDCIMS can detect potassium with high sensitivity with this technique.

  19. Inelastic scattering of OH radicals from organic liquids: isolating the thermal desorption channel.

    Science.gov (United States)

    King, Kerry L; Paterson, Grant; Rossi, Giovanni E; Iljina, Marija; Westacott, Robin E; Costen, Matthew L; McKendrick, Kenneth G

    2013-08-21

    Inelastic scattering of OH radicals from liquid surfaces has been investigated experimentally. An initially translationally and rotationally hot distribution of OH was generated by 193 nm photolysis of allyl alcohol. These radicals were scattered from an inert reference liquid, perfluorinated polyether (PFPE), and from the potentially reactive hydrocarbon liquids squalane (C30H62, 2,6,10,15,19,23-hexamethyltetracosane) and squalene (C30H50, trans-2,6,10,15,19,23-hexamethyltetracosa-2,6,10,14,18,22-hexaene). The scattered OH v = 0 products were detected by laser-induced fluorescence. Strong correlations were observed between the translational and rotational energies of the products. The high-N levels are translationally hot, consistent with a predominantly direct, impulsive scattering mechanism. Impulsive scattering also populates the lower-N levels, but a component of translationally relaxed OH, with thermal-desorption characteristics, can also be seen clearly for all three liquids. More of this translationally and rotationally relaxed OH survives from squalane than from squalene. Realistic molecular dynamics simulations confirm that double-bond sites are accessible at the squalene surface. This supports the proposition that relaxed OH may be lost on squalene via an addition mechanism.

  20. Implications of Using Thermal Desorption to Remediate Contaminated Agricultural Soil: Physical Characteristics and Hydraulic Processes.

    Science.gov (United States)

    O'Brien, Peter L; DeSutter, Thomas M; Casey, Francis X M; Derby, Nathan E; Wick, Abbey F

    2016-07-01

    Given the recent increase in crude oil production in regions with predominantly agricultural economies, the determination of methods that remediate oil contamination and allow for the land to return to crop production is increasingly relevant. Ex situ thermal desorption (TD) is a technique used to remediate crude oil pollution that allows for reuse of treated soil, but the properties of that treated soil are unknown. The objectives of this research were to characterize TD-treated soil and to describe implications in using TD to remediate agricultural soil. Native, noncontaminated topsoil and subsoil adjacent to an active remediation site were separately subjected to TD treatment at 350°C. Soil physical characteristics and hydraulic processes associated with agricultural productivity were assessed in the TD-treated samples and compared with untreated samples. Soil organic carbon decreased more than 25% in both the TD-treated topsoil and the subsoil, and total aggregation decreased by 20% in the topsoil but was unaffected in the subsoil. The alteration in these physical characteristics explains a 400% increase in saturated hydraulic conductivity in treated samples as well as a decrease in water retention at both field capacity and permanent wilting point. The changes in soil properties identified in this study suggest that TD-treated soils may still be suitable for sustaining vegetation, although likely at a slightly diminished capacity when directly compared with untreated soils.

  1. Suppression of PCDD/Fs during thermal desorption of PCBs-contaminated soil.

    Science.gov (United States)

    Zhao, Zhonghua; Ni, Mingjiang; Li, Xiaodong; Buekens, Alfons; Yan, Jianhua

    2016-12-01

    Thermal treatment of polychlorinated biphenyls (PCBs) contaminated soil was shown in earlier work to generate new PCBs, as well as polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). In this study, this thermal desorption was conducted with addition of three distinct inhibitors, including ammonium sulphate, urea and calcium oxide, to inhibit the formation of PCDDs and PCDFs when remediating PCBs-contaminated soil. Experiments were conducted for 40 min at 400 °C after adding 1 wt.% of inhibitor. Both the total PCDD/Fs and international toxic equivalent quantity (I-TEQ) reduced when inhibitors were introduced. Of the three compounds tested, CaO shows the highest inhibition efficiency, 92.2 % for total PCDD/Fs and 95.6 % for I-TEQ. The amount of CaO added also influences the suppression efficiency of PCDD/Fs. These results suggest that promoting desorption and destruction of precursors is probably the mechanism of suppression.

  2. Precursor ion scan profiles of acylcarnitines by atmospheric pressure thermal desorption chemical ionization tandem mass spectrometry.

    Science.gov (United States)

    Paglia, Giuseppe; D'Apolito, Oceania; Corso, Gaetano

    2008-12-01

    The fatty acyl esters of L-carnitine (acylcarnitines) are useful biomarkers for the diagnosis of some inborn errors of metabolism analyzed by liquid chromatography/tandem mass spectrometry. In this study the acylcarnitines were analyzed by atmospheric pressure thermal desorption chemical ionization using a commercial tandem mass spectrometer (APTDCI-MS/MS). The method is based on the precursor ion scan mode determination of underivatized acylcarnitines desorbed from samples by a hot desolvation gas flow and ionized by a corona pin discharge. During desorption/ionization step the temperature induces the degradation of acylcarnitines; nevertheless, the common fragment to all acylcarnitines [MH-59](+) is useful for analyzing their profile. APTDCI parameters, including angle of collection and incidence, gas flows and temperatures, were optimized for acylcarnitines. The experiments were performed drying 2 microL of an equimolar mixture of acylcarnitine standards on a glass slide. The specificity was evaluated by comparing product ion spectra and the precursor ion spectra of 85 m/z of acylcarnitines obtained by the APTDCI method and by electrospray ionization flow injection analysis (ESI-FIA). The method was also employed to analyze acylcarnitines extracted from a pathological dried blood spot and a control. The method enables analysis of biological samples and recognition of some acylcarnitines that are diagnostic markers of inherited metabolic diseases. The intrinsic high-throughput analysis of the ambient desorption ionization methods offers a new opportunity either for its potential application in clinical chemistry and for the expanded screening of some inborn errors of metabolism.

  3. Rapid determination of nicotine in urine by direct thermal desorption ion trap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Wise, M.B.; Ilgner, R.H.; Guerin, M.R.

    1990-01-01

    The measurement of nicotine and cotinine in physiological fluids (urine, blood serum, and saliva) is widely used as a means of assessing human exposure to environmental tobacco smoke (ETS). Although numerous analytical methods exist for these measurements, they generally involve extensive sample preparation which increases cost and decreases sample throughput. We report the use of thermal desorption directly into an ion trap mass spectrometer (ITMS) for the rapid determination of nicotine and cotinine in urine. A 1{mu}L aliquot of urine is injected into a specially designed inlet and flash vaporized directly into an ITMS through an open-split capillary restrictor interface. Isobutane chemical ionization is used to generate (M+H){sup +} ions of the analytes and collision induced dissociation is used to generate characteristic fragment ions which are used to confirm their identity. Quantification is achieved by integrating the ion current for the characteristic ions and comparing with an external working curve. Detection limits are approximately 50 pg per analyte and the sample turnaround time is approximately 3 minutes without the need for extensive sample preparation. 12 refs., 5 figs.

  4. Operable Unit 7-13/14 in situ thermal desorption treatability study work plan

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, P.; Nickelson, D.; Hyde, R.

    1999-05-01

    This Work Plan provides technical details for conducting a treatability study that will evaluate the application of in situ thermal desorption (ISTD) to landfill waste at the Subsurface Disposal Area (SDA) at the Idaho National Engineering and Environmental Laboratory (INEEL). ISTD is a form of thermally enhanced vapor vacuum extraction that heats contaminated soil and waste underground to raise its temperature and thereby vaporize and destroy most organics. An aboveground vapor vacuum collection and treatment system then destroys or absorbs the remaining organics and vents carbon dioxide and water to the atmosphere. The technology is a byproduct of an advanced oil-well thermal extraction program. The purpose of the ISTD treatability study is to fill performance-based data gaps relative to off-gas system performance, administrative feasibility, effects of the treatment on radioactive contaminants, worker safety during mobilization and demobilization, and effects of landfill type waste on the process (time to remediate, subsidence potential, underground fires, etc.). By performing this treatability study, uncertainties associated with ISTD as a selected remedy will be reduced, providing a better foundation of remedial recommendations and ultimate selection of remedial actions for the SDA.

  5. Non-thermal desorption from interstellar dust grains via exothermic surface reactions

    CERN Document Server

    Garrod, R T; Herbst, E

    2007-01-01

    Aims: The gas-phase abundance of methanol in dark quiescent cores in the interstellar medium cannot be explained by gas-phase chemistry. In fact, the only possible synthesis of this species appears to be production on the surfaces of dust grains followed by desorption into the gas. Yet, evaporation is inefficient for heavy molecules such as methanol at the typical temperature of 10 K. It is necessary then to consider non-thermal mechanisms for desorption. But, if such mechanisms are considered for the production of methanol, they must be considered for all surface species. Methods: Our gas-grain network of reactions has been altered by the inclusion of a non-thermal desorption mechanism in which the exothermicity of surface addition reactions is utilized to break the bond between the product species and the surface. Our estimated rate for this process derives from a simple version of classical unimolecular rate theory with a variable parameter only loosely contrained by theoretical work. Results: Our results ...

  6. Helium implanted Eurofer97 characterized by positron beam Doppler broadening and Thermal Desorption Spectroscopy

    Science.gov (United States)

    Carvalho, I.; Schut, H.; Fedorov, A.; Luzginova, N.; Desgardin, P.; Sietsma, J.

    2013-11-01

    Reduced Activation Ferritic/Martensitic steels are being extensively studied because of their foreseen application in fusion and Generation IV fission reactors. To produce irradiation induced defects, Eurofer97 samples were implanted with helium at energies of 500 keV and 2 MeV and doses of 1 × 1015-1016 He/cm2, creating atomic displacements in the range 0.07-0.08 dpa. The implantation induced defects were characterized by positron beam Doppler Broadening (DB) and Thermal Desorption Spectroscopy (TDS). Results show that up to ˜600 K peaks that can be attributed to He desorption from overpressured HenVm (n > m) clusters and vacancy assisted mechanism in the case of helium in the substitutional position. The temperature range 600-1200 K is related to the formation of larger clusters HenVm (n < m). The dissociation of the HeV and the phase transition attributed to a sharp peak in the TDS spectra at 1200 K. Above this temperature, the release of helium from bubbles is observed.

  7. Atomic force microscope controlled topographical imaging and proximal probe thermal desorption/ionization mass spectrometry imaging.

    Science.gov (United States)

    Ovchinnikova, Olga S; Kjoller, Kevin; Hurst, Gregory B; Pelletier, Dale A; Van Berkel, Gary J

    2014-01-21

    This paper reports on the development of a hybrid atmospheric pressure atomic force microscopy/mass spectrometry imaging system utilizing nanothermal analysis probes for thermal desorption surface sampling with subsequent atmospheric pressure chemical ionization and mass analysis. The basic instrumental setup and the general operation of the system were discussed, and optimized performance metrics were presented. The ability to correlate topographic images of a surface with atomic force microscopy and a mass spectral chemical image of the same surface, utilizing the same probe without moving the sample from the system, was demonstrated. Co-registered mass spectral chemical images and atomic force microscopy topographical images were obtained from inked patterns on paper as well as from a living bacterial colony on an agar gel. Spatial resolution of the topography images based on pixel size (0.2 μm × 0.8 μm) was better than the resolution of the mass spectral images (2.5 μm × 2.0 μm), which were limited by current mass spectral data acquisition rate and system detection levels.

  8. Surface reconstruction and thermal desorption: {O}/{Ag(110) } an experimental study

    Science.gov (United States)

    Canepa, M.; Salvietti, M.; Traverso, M.; Mattera, L.

    1995-07-01

    We have studied the associative desorption of oxygen from well-defined O( n×1)Ag(110) phases ( n ranging from 8 to 2) by thermal desorption mass spectrometry. Desorption peak profiles have been compared with calculations based on a lattice-gas model [V.P. Zhdanov, Surf. Sci. 277 (1992) 155] which takes into account the missing-row reconstruction of the substrate and adsorbate-adsorbate interactions along independent OAgO rows. The model works well at low coverage accurately reproducing the peak profiles. For the O(8 × 1), O(6 × 1) and O(4 × 1) phases, assuming a value of v = 10 15 s -1 for the pre-factor, values of ≈ 39 kcal/mol for the activation energy and ≈ -2.5 kcal/mol for the OO effective oxygen-oxygen interaction along OAgO rows are obtained. At high coverage the assumption of independence of OAgO chains is no longer valid and repulsive interactions perpendicularly to the chains have to be taken into account.

  9. Effects of He, D interaction on thermal desorption of He and D2 and microstructural evolution in pure Fe

    Science.gov (United States)

    Xu, Q.; Zhang, J.

    2016-10-01

    He and H atoms are produced in (n, α) and (n, p) nuclear reactions. In fusion reactors, energetic T and D, being isotopes of H, and He particles damage the surface materials. To investigate the He-D interaction, Fe, which is a model metal of choice in ferritic stainless steel that is used in fusion reactors, was irradiated separately by He or D2 ions and by combinations of He + D2 or D2 + He ions with the energy of 5 keV. The dose for single-species irradiation and each step of double-species irradiation was 1.0 × 1020 ions/m2. Thermal desorption analysis indicates that, in the case of single ion species irradiation, thermal desorption of D occurs at temperatures below 700 K, while the main thermal desorption of He occurs at 750 K and above 1200 K. The binding energy of He and defects is higher than that of D and defects. In the case of irradiation with combinations of ions species, however, the obtained thermal desorption spectra are the same, although the peak intensities are different, suggesting that the He-D interaction is weak. The sorption of D is more predominant for irradiations with He + D2. On the microstructure level, the irradiated samples exhibited larger voids following combined irradiations compared with those for irradiation with a single ion species after annealing to 1323 K. During the He + D2 irradiation, D atoms are effectively trapped owing to the defects induced by pre-irradiation with He.

  10. Polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran formation and emission in the thermal desorption waste treatment process

    Energy Technology Data Exchange (ETDEWEB)

    Leckey, J.H.

    1995-03-01

    It is extremely unlikely that significant amounts of polychlorinated dibenzo-p-dioxins (PCDDs) or polychlorinated dibenzofurans (PCDFs) will be emitted in the off-gas stream from the thermal desorption process, or the treated waste, particularly if the baseline design and anticipated operating conditions of the enhanced bench-scale (EBS) system are used. However, because of the acute toxicity of these compounds and because most of the data on their formation have been extrapolated from studies more related to incineration and fire conditions than thermal desorption, specific laboratory tests and specific EBS runs should be performed to monitor the rate of emission of PCDDs and PCDFs under thermal desorption conditions. In general, the following four conditions need to exist for significant amounts of PCDD or PCDF to be formed: (1) the presence of fly ash; (2) the presence of an oxidizing source; (3) a suitable temperature, and (4) the presence of a suitable precursor. Although the EBS system provides some of these conditions, it is unlikely that enough fly ash will be produced in the system to allow a significant amount of PCDD or PCDF formation. Additionally, particulate matter controls will be used to remove airborne particulates from the gas phase. If PCDD/Fs are presented in a waste stream being evaluated in the EBS, they will likely volatilize in the kiln and subsequently condense in the venturi scrubber system.

  11. Filtration efficiency validation of glass wool during thermal desorption-gas chromatography-mass spectrometer analysis of fine atmospheric particles.

    Science.gov (United States)

    Hao, Liang; Wu, Dapeng; Ding, Kun; Meng, Hu; Yan, Xiaohui; Guan, Yafeng

    2015-02-06

    Thermal desorption-gas chromatography-mass spectrometer (TD-GC-MS) technique has been widely used for analysis of semi-violate organic compounds on atmospheric aerosol. To prevent GC column from being damaged by fine solid particles during thermal desorption process, glass wool as filter mat is indispensible. However, the filtration efficiency has never been validated. In this paper, the most penetrating particle size and the minimum packing thickness of glass wool were calculated based on classical filtration theory. According to the calculation results, packing parameters of glass wool were optimized experimentally using silica particles. It is demonstrated that glass wool with a packing thickness of 30 mm, solidity of 0.039 can effectively block these fine solid particles from penetrating at normal thermal desorption conditions (T=300°C, u=0.4-4 cm/s). Finally, the filtration efficiency of glass wool was further confirmed with real PM2.5 samples. Under the validated filtration condition, TD-GC-MS was applied for the analysis of non-polar organic compounds on real PM2.5 samples, and very good results were obtained.

  12. Impact of Thermal Decomposition on Thermal Desorption Instruments: Advantage of Thermogram Analysis for Quantifying Volatility Distributions of Organic Species.

    Science.gov (United States)

    Stark, Harald; Yatavelli, Reddy L N; Thompson, Samantha L; Kang, Hyungu; Krechmer, Jordan E; Kimmel, Joel R; Palm, Brett B; Hu, Weiwei; Hayes, Patrick L; Day, Douglas A; Campuzano-Jost, Pedro; Canagaratna, Manjula R; Jayne, John T; Worsnop, Douglas R; Jimenez, Jose L

    2017-08-01

    We present results from a high-resolution chemical ionization time-of-flight mass spectrometer (HRToF-CIMS), operated with two different thermal desorption inlets, designed to characterize the gas and aerosol composition. Data from two field campaigns at forested sites are shown. Particle volatility distributions are estimated using three different methods: thermograms, elemental formulas, and measured partitioning. Thermogram-based results are consistent with those from an aerosol mass spectrometer (AMS) with a thermal denuder, implying that thermal desorption is reproducible across very different experimental setups. Estimated volatilities from the detected elemental formulas are much higher than from thermograms since many of the detected species are thermal decomposition products rather than actual SOA molecules. We show that up to 65% of citric acid decomposes substantially in the FIGAERO-CIMS, with ∼20% of its mass detected as gas-phase CO2, CO, and H2O. Once thermal decomposition effects on the detected formulas are taken into account, formula-derived volatilities can be reconciled with the thermogram method. The volatility distribution estimated from partitioning measurements is very narrow, likely due to signal-to-noise limits in the measurements. Our findings indicate that many commonly used thermal desorption methods might lead to inaccurate results when estimating volatilities from observed ion formulas found in SOA. The volatility distributions from the thermogram method are likely the closest to the real distributions.

  13. Identification of sink spots in two thermal desorption GC/MS systems for the analysis of polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Li, Yingjie; Zhu, Jiping

    2017-04-08

    Thermal desorption (TD) GC/MS has been used for the analysis of polycyclic aromatic hydrocarbons (PAHs) and other semi-volatile organic compounds. However, thermal desorption recovery of PAHs have not been well studied and the cause of PAH residues in a TD system has not been clearly understood. Our results showed that low volatility of PAHs can lead to their incomplete recovery in a TD system: for the PAHs with low vapour pressures, up to 10% and 3% could be lost in a two-stage (TS) TD system and a short-path (SP) TD system, respectively. Within the TSTD system, the majority of residues were found in the 4-port valve and in the spot where internal trap and the 4-port valve connects. Within the SPTD system, residues were largely confined to the tube needle connecting the sample tube and GC injection port as well as inside the injection port. Since the volatility of PAHs can represent the range typical of semi-volatile organic compounds (SVOCs), our results have a wide implication for the thermal desorption of SVOCs in general. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  14. Charge creation and nucleation of the longitudinal plasma wave in coupled Josephson junctions

    Science.gov (United States)

    Shukrinov, Yu. M.; Hamdipour, M.

    2010-11-01

    We study the phase dynamics in coupled Josephson junctions described by a system of nonlinear differential equations. Results of detailed numerical simulations of charge creation in the superconducting layers and the longitudinal plasma wave (LPW) nucleation are presented. We demonstrate the different time stages in the development of the LPW and present the results of FFT analysis at different values of bias current. The correspondence between the breakpoint position on the outermost branch of current voltage characteristics (CVC) and the growing region in time dependence of the electric charge in the superconducting layer is established. The effects of noise in the bias current and the external microwave radiation on the charge dynamics of the coupled Josephson junctions are found. These effects introduce a way to regulate the process of LPW nucleation in the stack of IJJ.

  15. Age determination of ballpoint pen ink by thermal desorption and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Bügler, Jürgen H; Buchner, Hans; Dallmayer, Anton

    2008-07-01

    Two main approaches can be used for determining the age of an ink: indirect dating and direct dating. Indirect dating is based on the chemical analysis of an ink followed by comparison with known samples in a reference collection. The collection should contain information about the inks including the market introduction dates. This approach may allow for an anachronism to be detected. The second concept is based on measuring ink components that change with age. The analysis of solvents in ballpoint inks may be a useful parameter for determining the age of ink on paper. In a previous study, the authors demonstrated that thermal desorption of ink directly from paper, followed by chemical analysis using gas chromatography-mass spectrometry (GC-MS), is a promising procedure for characterizing ink-binder resins and solvents. Preliminary tests showed that monitoring the evaporation of ink solvent from ink on paper is not a suitable method for ink dating. Thermal analysis of ink on paper in two steps revealed that fresh ink releases a relative amount of solvent at a certain low temperature in a defined period of time, which decreases as the ink ages. As a consequence, this relative amount of solvent released at a certain low temperature, and its decrease with time, can be used to estimate ink age. This age-dependent parameter was studied in 85 different inks ranging in age from 1 week to 1.5 years. It was found that some inks showed a significant decrease of this parameter up to an age of several months, and that the aging process can be monitored within this period. For other inks, however, the age-dependent parameter decreases relatively fast, e.g., within a few days, to a constant level, which can be too fast for casework. Based on these results, a general procedure for assessing the age of ballpoint pen inks on paper was developed.

  16. Trapping state of hydrogen isotopes in carbon and graphite investigated by thermal desorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Atsumi, H. [Department of Electric and Electronic Engineering, Kinki University, Higashiosaka (Japan); Tanabe, T. [Interdisciplinary Graduat School of Engineering Sciences, Kyushu University, Fukuoka (Japan); Shikama, T. [Institute for Materials Research, Tohoku University, Sendai (Japan)

    2015-03-15

    Thermal desorption spectrometry (TDS) has been investigated to obtain fundamental information of tritium behavior in graphite and carbon materials especially at high temperatures. 29 brands of graphite, HOPG, glassy carbon and CFC materials charged with deuterium gas are tested up to the temperature of 1735 K with a heating rate of 0.1 K/s. TDS spectra have five peaks at 600-700 K, around 900 K, 1200 K, 1300-1450 K and 1600-1650 K. The amounts of released deuterium have been compared with crystallographic parameters derived from XRD analysis. The results can be summarized as follows. First, TDS spectra of deuterium were quite varied among the samples tested, such as existence of peaks, peak temperatures and release amounts of deuterium. Secondly, TDS spectra may consist of five peaks, which are peak 1 (600-700 K), peak 2 (around 900 K), peak 3 (around 1200 K), peak 4 (1300-1450 K) and peak 5 (1600-1650 K). Thirdly, the correlations between the estimated surface area of edge surface and the total amount of released deuterium could be observed for peaks 4 and 5. Fourthly, high energy trapping site (peak 5) may exist even at edge surface or a near surface region, not only for intercalary. And fifth, in order to obtain the lower tritium retention for graphite and CFC materials, the material should be composed of a filler grain with a smaller crystallite size or having the smaller net edge surface in its structure. It is shown that heat treatment does not reduce originally existing trapping sites but trapping sites generated by neutron irradiation for instance can be reduced in some degree.

  17. Plasma etched surface scanning inspection recipe creation based on bidirectional reflectance distribution function and polystyrene latex spheres

    Science.gov (United States)

    Saldana, Tiffany; McGarvey, Steve; Ayres, Steve

    2014-04-01

    The continual increasing demands upon Plasma Etching systems to self-clean and continue Plasma Etching with minimal downtime allows for the examination of SiCN, SiO2 and SiN defectivity based upon Surface Scanning Inspection Systems (SSIS) wafer scan results. Historically all Surface Scanning Inspection System wafer scanning recipes have been based upon Polystyrene Spheres wafer deposition for each film stack and the subsequent creation of light scattering sizing response curves. This paper explores the feasibility of the elimination of Polystyrene Latex Sphere (PSL) and/or process particle deposition on both filmed and bare Silicon wafers prior to Surface Scanning Inspection System recipe creation. The study will explore the theoretical maximal Surface Scanning Inspection System sensitivity based on PSL recipe creation in conjunction with the maximal sensitivity derived from Bidirectional Reflectance Distribution Function (BRDF) maximal sensitivity modeling recipe creation. The surface roughness (Root Mean Square) of plasma etched wafers varies dependent upon the process film stack. Decrease of the root mean square value of the wafer sample surface equates to higher surface scanning inspection system sensitivity. Maximal sensitivity SSIS scan results from bare and filmed wafers inspected with recipes created based upon Polystyrene/Particle Deposition and recipes created based upon BRDF modeling will be overlaid against each other to determine maximal sensitivity and capture rate for each type of recipe that was created with differing recipe creation modes. A statistically valid sample of defects from each Surface Scanning Inspection system recipe creation mode and each bare wafer/filmed substrate will be reviewed post SSIS System processing on a Defect Review Scanning Electron Microscope (DRSEM). Native defects, Polystyrene Latex Spheres will be collected from each statistically valid defect bin category/size. The data collected from the DRSEM will be utilized to

  18. Quantification of diesel exhaust gas phase organics by a thermal desorption proton transfer reaction mass spectrometer

    Directory of Open Access Journals (Sweden)

    M. H. Erickson

    2012-02-01

    Full Text Available A new approach was developed to measure the total abundance of long chain alkanes (C12 and above in urban air using thermal desorption with a proton transfer reaction mass spectrometer (PTR-MS. These species are emitted in diesel exhaust and may be important precursors to secondary organic aerosol production in urban areas. Long chain alkanes undergo dissociative proton transfer reactions forming a series of fragment ions with formula CnH2n+1. The yield of the fragment ions is a function of drift conditions. At a drift field strength of 80 Townsends, the most abundant ion fragments from C10 to C16 n-alkanes were m/z 57, 71 and 85. The PTR-MS is insensitive to n-alkanes less than C8 but displays an increasing sensitivity for larger alkanes. Higher drift field strengths yield greater normalized sensitivity implying that the proton affinity of the long chain n-alkanes is less than H2O. Analysis of diesel fuel shows the mass spectrum was dominated by alkanes (CnH2n+1, monocyclic aromatics, and an ion group with formula CnH2n−1 (m/z 97, 111, 125, 139. The PTR-MS was deployed in Sacramento, CA during the Carbonaceous Aerosols and Radiative Effects Study field experiment in June 2010. The ratio of the m/z 97 to 85 ion intensities in ambient air matched that found in diesel fuel. Total diesel exhaust alkane concentrations calculated from the measured abundance of m/z 85 ranged from the method detection limit of ~1 μg m−3 to 100 μg m−3 in several air pollution episodes. The total diesel exhaust alkane concentration determined by this method was on average a factor of 10 greater than the sum of alkylbenzenes associated with spark ignition vehicle exhaust.

  19. The use of thermal desorption in monitoring for the chemical weapons demilitarization program.

    Science.gov (United States)

    Harper, Martin

    2002-10-01

    Under international treaty, the United States and Russia are disposing of their aging stockpile of chemical weapons. Incineration and chemical neutralization are options for sites in the United States, although Russia prefers the latter. The storage and disposal of bulk and chemical agents and weapons involve unique hazards of handling extremely toxic materials. There are three major areas of concern--the storage stockpile, the disposal area, and the discovery and destruction of "found" material not considered part of the stockpile. Methods have been developed to detect the presence of chemical agents in the air, and these are used to help assure worker protection and the safety of the local population. Exposure limits for all chemical agents are low, sometimes nanograms per cubic meter for worker control limits and picograms per cubic meter for general population limits. There are three types of monitoring used in the USA: alarm, confirmation, and historical. Alarm monitors are required to give relatively immediate real-time responses to agent leaks. They are simple to operate and rugged, and provide an alarm in near real-time (generally a few minutes). Alarm monitors for the demilitarization program are based on sorbent pre-concentration followed by thermal desorption and simple gas chromatography. Alarms may need to be confirmed by another method, such as sample tubes collocated with the alarm monitor and analyzed in a laboratory by more sophisticated chromatography. Sample tubes are also used for historical perimeter monitoring, with sample periods typically of 12 h. The most common detector is the flame photometric detector, in sulfur or phosphorous mode, although others, such as mass-selective detectors, also have been used. All agents have specific problems with collection, chromatography and detection. Monitoring is not made easier by interferences from pesticide spraying, busy roadways or military firing ranges. Exposure limits drive the requirements for

  20. Non-isothermal kinetics of the thermal desorption of mercury from a contaminated soil

    Directory of Open Access Journals (Sweden)

    López, Félix A.

    2014-03-01

    Full Text Available The Almadén mining district (Ciudad Real, Spain was the largest cinnabar (mercury sulphide mine in the world. Its soils have high levels of mercury a consequence of its natural lithology, but often made much worse by its mining history. The present work examines the thermal desorption of two contaminated soils from the Almadén area under non-isothermal conditions in a N2 atmosphere, using differential scanning calorimetry (DSC. DSC was performed at different heating rates between room temperature and 600 °C. Desorption temperatures for different mercury species were determined. The Friedman, Flynn-Wall-Ozawa and Coasts–Redfern methods were employed to determine the reaction kinetics from the DSC data. The activation energy and pre-exponential factor for mercury desorption were calculated.El distrito minero de Almadén (Ciudad Real, España tiene la mayor mina de cinabrio (sulfuro de mercurio del mundo. Sus suelos tienen altos niveles de mercurio como consecuencia de su litología natural, pero a menudo su contenido en mercurio es mucho más alto debido a la historia minera de la zona. Este trabajo examina la desorción térmica de dos suelos contaminados procedentes de Almadén bajo condiciones isotérmicas en atmósfera de N2, empleando calorimetría diferencial de barrido (DSC. La calorimetría se llevó a cabo a diferentes velocidades de calentamiento desde temperatura ambiente hasta 600 °C. Se determinaron las diferentes temperaturas de desorción de las especies de mercurio presentes en los suelos. Para determinar la cinética de reacción a partir de los datos de DSC se utilizaron los métodos de Friedman, Flynn-Wall-Ozawa y Coasts–Redfern. Además se calcularon las energías de activación y los factores pre-exponenciales para la desorción del mercurio.

  1. Broad spectrum infrared thermal desorption of wipe-based explosive and narcotic samples for trace mass spectrometric detection.

    Science.gov (United States)

    Forbes, Thomas P; Staymates, Matthew; Sisco, Edward

    2017-08-07

    Wipe collected analytes were thermally desorbed using broad spectrum near infrared heating for mass spectrometric detection. Employing a twin tube filament-based infrared emitter, rapid and efficiently powered thermal desorption and detection of nanogram levels of explosives and narcotics was demonstrated. The infrared thermal desorption (IRTD) platform developed here used multi-mode heating (direct radiation and secondary conduction from substrate and subsequent convection from air) and a temperature ramp to efficiently desorb analytes with vapor pressures across eight orders of magnitude. The wipe substrate experienced heating rates up to (85 ± 2) °C s(-1) with a time constant of (3.9 ± 0.2) s for 100% power emission. The detection of trace analytes was also demonstrated from complex mixtures, including plastic-bonded explosives and exogenous narcotics, explosives, and metabolites from collected artificial latent fingerprints. Manipulation of the emission power and duration directly controlled the heating rate and maximum temperature, enabling differential thermal desorption and a level of upstream separation for enhanced specificity. Transitioning from 100% power and 5 s emission duration to 25% power and 30 s emission enabled an order of magnitude increase in the temporal separation (single seconds to tens of seconds) of the desorption of volatile and semi-volatile species within a collected fingerprint. This mode of operation reduced local gas-phase concentrations, reducing matrix effects experienced with high concentration mixtures. IRTD provides a unique platform for the desorption of trace analytes from wipe collections, an area of importance to the security sector, transportation agencies, and customs and border protection.

  2. Direct thermal desorption of semivolatile organic compounds from diffusion denuders and gas chromatographic analysis for trace concentration measurement.

    Energy Technology Data Exchange (ETDEWEB)

    Tobias, D. E.; Perlinger, J. A.; Morrow, P. S.; Doskey, P. V.; Perram, D.L.; Environmental Science Division; Michigan Technological Univ.

    2007-01-01

    A novel method for collection and analysis of vapor-phase semivolatile organic compounds (SOCs) in ambient air is presented. The method utilizes thermal desorption of SOCs trapped in diffusion denuders coupled with cryogenic preconcentration on Tenax-TA and analysis by high resolution gas chromatography (GC)-electron-capture detection (ECD). The sampling and analysis methods employ custom-fabricated multicapillary diffusion denuders, a hot gas spike (HGS) apparatus to load known quantities of thermally stable standards into diffusion denuders prior to sample collection, a custom-fabricated oven to thermally desorb SOCs from the diffusion denuder, and a programmable temperature vaporization (PTV) inlet containing a liner packed with Tenax-TA for effective preconcentration of the analytes and water management. High flow rates into the PTV inlet of 750 mL min-1during thermal desorption are ca. a factor of ten greater than typically used. To improve resolution and retention time stability, the thermal desorption and PTV inlet programming procedure includes three steps to prevent water from entering the analytic column while effectively transferring the analytes into the GC system. The instrumentation and procedures provide virtually complete and consistent transfer of analytes collected from ambient air into the GC evidenced by recovery of seven replicates of four internal standards of 90.7 {+-} 4.0-120 {+-} 23% (mean {+-} 95% confidence interval, CI). Retention time based compound identification is facilitated by low retention time variability with an average 95% CI of 0.024 min for sixteen replicates of eight standards. Procedure details and performance metrics as well as ambient sampling results are presented.

  3. Direct thermal desorption of semivolatile organic compounds from diffusion denuders and gas chromatographic analysis for trace concentration measurement.

    Science.gov (United States)

    Tobias, David E; Perlinger, Judith A; Morrow, Patrick S; Doskey, Paul V; Perram, David L

    2007-01-26

    A novel method for collection and analysis of vapor-phase semivolatile organic compounds (SOCs) in ambient air is presented. The method utilizes thermal desorption of SOCs trapped in diffusion denuders coupled with cryogenic preconcentration on Tenax-TA and analysis by high resolution gas chromatography (GC)-electron-capture detection (ECD). The sampling and analysis methods employ custom-fabricated multicapillary diffusion denuders, a hot gas spike (HGS) apparatus to load known quantities of thermally stable standards into diffusion denuders prior to sample collection, a custom-fabricated oven to thermally desorb SOCs from the diffusion denuder, and a programmable temperature vaporization (PTV) inlet containing a liner packed with Tenax-TA for effective preconcentration of the analytes and water management. High flow rates into the PTV inlet of 750mLmin(-1)during thermal desorption are ca. a factor of ten greater than typically used. To improve resolution and retention time stability, the thermal desorption and PTV inlet programming procedure includes three steps to prevent water from entering the analytic column while effectively transferring the analytes into the GC system. The instrumentation and procedures provide virtually complete and consistent transfer of analytes collected from ambient air into the GC evidenced by recovery of seven replicates of four internal standards of 90.7+/-4.0-120+/-23% (mean+/-95% confidence interval, CI). Retention time based compound identification is facilitated by low retention time variability with an average 95% CI of 0.024min for sixteen replicates of eight standards. Procedure details and performance metrics as well as ambient sampling results are presented.

  4. Development of a thermal desorption-gas chromatography-mass spectrometry method for determining personal care products in air.

    Science.gov (United States)

    Ramírez, Noelia; Marcé, Rosa Maria; Borrull, Francesc

    2010-06-25

    This study describes the development of a new analytical method for determining 14 personal care products (PCPs) - nine synthetic musks, four parabens and one insect repellent - in air samples. The method is based on active sampling on sorbent tubes and thermal desorption-gas chromatography-mass spectrometry analysis, and is rapid, sensitive and drastically reduces the risk of sample contamination. Three kinds of tubes and traps were tested, those filled with Tenax TA being the most suitable for this study. Method validation showed good repeatability and reproducibility, low detection limits (between 0.03 ng m(-3) for DPMI and 12.5 ng m(-3) for propyl paraben) and good linearity for all compounds. Stability during storage indicated that samples must be kept refrigerated at 4 degrees C and analysed within 1 week of collection. The applicability of the technique to real samples was tested in different indoor and outdoor atmospheres. The total PCP values for indoor air ranged from 135 ng m(-3) in a pharmacy to 2838 ng m(-3) in a hairdresser's, whereas the values for outdoor air ranged from 14 ng m(-3) for a suburban environment to 26 ng m(-3) for an urban environment. In general, the most abundant synthetic musks were galaxolide (5.9-1256 ng m(-3)), musk xylene (1.6-766 ng m(-3)) and tonalide (1.1-138 ng m(-3)). Methyl and ethyl paraben (2.4-313 ng m(-3) and 1.8-117 ng m(-3), respectively) were the most abundant parabens. Although thermal desorption methods have been widely used for determining volatile organic compounds, they are rarely used with semi-volatile compounds. This study thus demonstrates that the thermal desorption method performs well with semi-volatile compounds and, for the first time, that it can be used for determining PCPs.

  5. Thermal desorption-gas chromatography for the determination of benzene, aniline, nitrobenzene and chlorobenzene in workplace air.

    Science.gov (United States)

    Patil, S F; Lonkar, S T

    1992-05-29

    Sampling on Tenax TA of different mesh sizes followed by thermal desorption and gas chromatography was evaluated as a simple method for the determination of benzene, aniline, nitrobenzene and chlorobenzene in the workplace air. An alternative sampling technique in place of pump sampling was developed. Quantitative recoveries were obtained in the mass range 0.04-10 micrograms. It was found that air humidity had no effect on recovery. The charged tubes can be stored at room temperature for 5 days with no change in recovery. The particle size of Tenax TA has no significant effect on adsorption and desorption.

  6. Biological functioning of PAH-polluted and thermal desorption-treated soils assessed by fauna and microbial bioindicators.

    Science.gov (United States)

    Cébron, Aurélie; Cortet, Jérôme; Criquet, Stéven; Biaz, Asmaa; Calvert, Virgile; Caupert, Cécile; Pernin, Céline; Leyval, Corinne

    2011-11-01

    A large number of soil bioindicators were used to assess biological diversity and activity in soil polluted with polycyclic aromatic hydrocarbons (PAHs) and the same soil after thermal desorption (TD) treatment. Abundance and biodiversity of bacteria, fungi, protozoa, nematodes and microarthropods, as well as functional parameters such as enzymatic activities and soil respiration, were assessed during a two year period of in situ monitoring. We investigated the influence of vegetation (spontaneous vegetation and Medicago sativa) and TD treatment on biological functioning. Multivariate analysis was performed to analyze the whole data set. A principal response curve (PRC) technique was used to evaluate the different treatments (various vegetation and contaminated vs. TD soil) contrasted with control (bare) soil over time. Our results indicated the value of using a number of complementary bioindicators, describing both diversity and functions, to assess the influence of vegetation on soil and discriminate polluted from thermal desorption (TD)-treated soil. Plants had an influence on the abundance and activity of all organisms examined in our study, favoring the whole trophic chain development. However, although TD-treated soil had a high abundance and diversity of microorganisms and fauna, enzymatic activities were weak because of the strong physical and chemical modifications of this soil. Copyright © 2011 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  7. Application of Thermal Desorption Unit (TDU) to treat low-toxicity mineral oil base cuttings in Barinas District, Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Rendon, Ruben [Petroleos de Venezuela, Caracas (Venezuela); Luzardo, Janeth; Alcoba, Alcides [M-I SWACO, Houston, TX (United States)

    2008-07-01

    The potential environmental impact of oil-based drill cuttings is generating increased scrutiny in the oil and gas industry. If left untreated, oil-based cuttings not only increase the risk of environmental liabilities, but also affect revenue, as drilling generates wastes that in most cases require special treatment before disposal. Consequently, the oil industry is looking for technologies to help minimize environmental liabilities. Accordingly, the Barinas District of PDVSA has started a pilot trial to treat oil-based drilling cuttings by applying thermal desorption technology. The main objective of this technology is recovering trapped hydrocarbons, while minimizing wastes and preparing solids to be disposed of through a mobile treatment plant. This novel technology has been used worldwide to treat organic pollutants in soil. Thermal desorption is a technology based on the application of heat in soils polluted with organic compounds. With this technology, target temperatures vary according to the type and concentration of detected pollutants along with its characterization, in such a way that compounds are disposed of by volatilization. As part of the integral waste management development along with the pilot trial for hydrocarbon-contaminated solid waste treatment, trials on soils were undertaken by applying process-generated ashes in equally-sized bins, with different mixtures (ashes, ashes organic material, ashes-organic material-sand, ashes-land). The resulting process offers an immediate soil remediation and final disposal solution for toxic and dangerous waste. (author)

  8. Cloud point extraction and gas chromatography with direct microvial insert thermal desorption for the determination of haloanisoles in alcoholic beverages.

    Science.gov (United States)

    Cacho, J I; Campillo, N; Viñas, P; Hernández-Córdoba, M

    2016-11-01

    A sensitive analytical procedure for the determination of four haloanisoles (2,4,6 trichloroanisole, 2,4,6-tribromoanisole, 2,3,4,6-tetrachloroanisole and pentachloroanisole) related with cork taint defects in wines, in different types of alcoholic beverages has been developed. The analytes were extracted from the matrix samples by cloud point extraction (CPE) using Triton X-114 heated to 75°C, and the surfactant rich phase was separated by centrifugation. By means of direct microvial insert thermal desorption, 20µL of the CPE obtained extract was submitted to gas chromatography-mass spectrometry (GC-MS) analysis. The parameters affecting the CPE and microvial insert thermal desorption were optimized. Quantification was carried by matrix-matched calibration using an internal standard. Detection limits ranged between 12.9 and 20.8ngL(-1), depending on the compound, for beer and wine samples, whereas for whiskies values in the 46.3-48ngL(-1) range were obtained, since these samples were diluted for analysis. Recoveries for alcoholic beverages were in the 89-111% range, depending on the analyte and the sample.

  9. Rapid identification of pesticides in human oral fluid for emergency management by thermal desorption electrospray ionization/mass spectrometry.

    Science.gov (United States)

    Lee, Chi-Wei; Su, Hung; Chen, Peng-Yu; Lin, Shiang-Jiun; Shiea, Jentaie; Shin, Shyi-Jang; Chen, Bai-Hsiun

    2016-02-01

    Self-poisoning with pesticides accounts for approximately one-third of all suicides worldwide. To expedite rescue in the emergency department, it is essential to develop a point-of-care analytical method for rapid identification of ingested pesticides. In this study, five of the most common pesticides ingested by self-poisoning patients in Taiwan were analyzed from oral fluid samples. Pesticide-oral fluid mixtures were applied on a cotton swab and then transferred into methanol. A metallic probe was used to sample the methanol solution for subsequent thermal desorption-electrospray ionization mass spectrometry analysis. Altogether, pesticide sampling, transfer, desorption, ionization, and detection took less than 1 min. The reproducibility of this method (n = 6) was shown in the observed low-relative standard deviation (four human subjects by thermal desorption-electrospray ionization mass spectrometry were between 1-10 ppb with relative standard deviation 10.7%. Moreover, in this study, linear responses of five pesticides in oral fluid with concentrations between 1 ppb-1 ppm (R2 between 0.9938 and 0.9988) were observed. As the whole analytical process is extremely short, this technique allows for early non-invasive point-of-care identification of pesticides in the oral fluid of self-poisoning patients in the emergency room, providing important toxicological information for decision-making during critical resuscitation.

  10. Evaluation of Water Repellency in Petroleum Drilling Cuttings Treated by Thermal Desorption: Implications for Use in Construction and Agriculture

    Science.gov (United States)

    Domínguez-Rodríguez, Verónica I.; Guzmán-Osorio, Francisco J.; Adams Schroeder, Randy H.; Bautista-Margulis, Raúl G.

    2010-05-01

    Thermal desorption is one of many methods used for the remediation of hydrocarbon contaminated soils and similar materials. It has several advantages over competing technologies, especially with respect to treatment times. While the biological treatment of contaminated soils may take several months depending principally on the type of hydrocarbons and starting concentration, thermal desorption typically takes less than one month, depending on the treatment capacities of the equipment involved, and the volume of material requiring treatment. In the petroleum producing region of southeastern Mexico, this has been one of the principal methods used for the treatment of drilling cuttings, due mostly to the short time required. As with most remediation projects, as well as in the treatment of exploration and production (E&P) wastes, the criteria used to consider the remediation finalized is the concentration of hydrocarbons in the treated material. This is based on the supposition that at some (relatively low) hydrocarbon concentration, the toxicological affects are reduced to acceptable levels. However, little attention has been paid to the physical-chemical properties of supposedly treated material, which may suffer from water repellency, especially in thermal treatment methods. This could greatly reduce the options for final use of treated materials, especially to support plant growth. Conversely, there may be some construction uses of treated material in which some water repellence could be beneficial (caps for land fills, for example). Considering the relevance of the physical-chemical impacts of petroleum on soil and similar materials, we felt it was important to evaluate the efficiency of the principal method used to treat E&P wastes in Mexico (thermal desporption) based on these factors. In this study different operating conditions (temperature and residence time) of a sub-pilot scale thermal desorption unit were evaluated with respect not only to reduction in

  11. Thermal desorption study of catalytic systems. Communication 20. Adsorption of water vapors on the calcium aluminate components of catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Nissenbaum, V.D.; Danyushevskii, V.Y.; Golosman, E.Z.; Rubinstein, A.M.; Yakerson, V.I.

    1985-05-01

    Ca aluminates are used as a component of catalysts of gas-phase processes, some of which take place with the participation of water. Nickel calcium aluminate catalysts are thus used for hydrogenation of CO and CO/sub 2/ to CH/sub 4/ and water; zinc calcium aluminate catalysts are used for sulfur purification of process gases, where water is liberated during sulfiding of ZnO; and copper zinc calcium aluminate catalysts are used in low-temperature conversion of CO with water vapor. It is also known that Ca aluminates undergo various transformations in aqueous media with the formation of Ca hydroaluminates. This paper discusses the adsorption of water from the gas phase on calcium aluminate systems, which was investigated by the thermal desorption method. Samples of varying phase composition, different CaO/Al/sub 2/O/sub 3/ ratios, and specific surface areas were also studied and are reported on here.

  12. Analysis of roasted and unroasted Pistacia terebinthus volatiles using direct thermal desorption-GCxGC-TOF/MS.

    Science.gov (United States)

    Gogus, F; Ozel, M Z; Kocak, D; Hamilton, J F; Lewis, A C

    2011-12-01

    The objective of this study was to determine the effects of roasting time on volatile components of Pistacia terebinthus L., a fruit growing wild in Turkey. The whole fruit samples were pan roasted for 0, 5, 10, 15, 20 and 25min at 200°C. Volatile compounds were isolated and identified using the direct thermal desorption (DTD) method coupled with comprehensive gas chromatography - time of flight mass spectrometry (GCxGC-TOF/MS). The major components of the fresh hull of P. terebinthus were α-pinene (10.37%), limonene (8.93%), β-pinene (5.53%), 2-carene (4.47%) and γ-muurolene (4.29%). Eighty-three constituents were characterised from the volatiles of fresh whole P. terebinthus fruits obtained by direct thermal desorption with α-pinene (9.62%), limonene (5.54%), γ-cadinane (5.48%), β-pinene (5.46%), β-caryophyllene (5.24%) being the major constituents. The type and the number of constituents characterised were observed to change with differing roasting times. Limonene (5.56%), α-pinene (4.84%), 5-methylfurfural (4.78%), 5-hydroxymethylfurfural (5-HMF, 3.89%), dimethylmetoxyfuranone (3.67%) and 3-methyl-2(5H)furanone (3.12%) were identified as the major components among the 104 compounds characterised in the volatiles of P. terebinthus, roasted for 25min. In addition, volatiles of fully roasted P. terebinthus fruits contained furans and furanones (15.42%), pyridines (4.45%) and benzene derivatives (3.81%) as the major groups.

  13. Solid-phase extraction-thermal desorption-gas chromatography with mass selective detection for the determination of drugs in urine

    NARCIS (Netherlands)

    van Hout, MWJ; de Zeeuw, RA; Franke, JP; de Jong, GJ

    2003-01-01

    Solid-phase extraction (SPE) was combined with thermal desorption (TD) and gas chromatographic (GC) analysis to determine drugs in urine. The extraction was performed inside a fritted GC liner using about 5 mg TENAX that was inserted into the liner on top of the frit. After extraction, the liner was

  14. Characterization of olive oil volatiles by multi-step direct thermal desorption-comprehensive gas chromatography-time-of-flight mass spectrometry using a programmed temperature vaporizing injector

    NARCIS (Netherlands)

    de Koning, S.; Kaal, E.; Janssen, H.-G.; van Platerink, C.; Brinkman, U.A.Th.

    2008-01-01

    The feasibility of a versatile system for multi-step direct thermal desorption (DTD) coupled to comprehensive gas chromatography (GC × GC) with time-of-flight mass spectrometric (TOF-MS) detection is studied. As an application the system is used for the characterization of fresh versus aged olive oi

  15. Determination of off-flavor compounds, 2-methylisoborneol and geosmin, in salmon fillets using stir bar sorptive extraction–thermal desorption coupled with gas chromatography–mass spectrometry

    Science.gov (United States)

    A sensitive and solvent-less method for the determination of musty and earthy off-flavor compounds, 2-methylisoborneol (MIB) and geosmin (GSM), in salmon tissue was developed using stir bar sorptive extraction -thermal desorption coupled with gas chromatography -mass spectrometry (SBSE -TD -GCMS). M...

  16. 24-HOUR DIFFUSIVE SAMPLING OF 1,3-BUTADIENE IN AIR ONTO CARBOPACK X SOLID ADSORBENT FOLLOWED BY THERMAL DESORPTION/GC/MS ANALYSIS - FEASIBILITY STUDY

    Science.gov (United States)

    Diffusive sampling of 1,3-butadiene for 24 hr onto the graphitic adsorbent Carbopack X packed in a stainless steel tube badge (6.3 mm o.d., 5 mm i.d., and 90 mm in length) with analysis by thermal desorption/gas chromatography (GC)/mass spectrometry (MS) has been evaluated in con...

  17. Thermal Desorption/Ultraviolet Photolysis Process Technology Research, Test, and Evaluation Performed at the Naval Construction Battalion Center, Gulfport, Mississippi, for the USAF Installation Restoration Program. Volume 2

    Science.gov (United States)

    1987-12-01

    packed in ice. Sampling of vent gas and off- gases from the two thermal desorption technologies will be performie using procedures and techniques...solvent used in it. wash with hot voat Cenaslunug detergent.. inse with copioua aMunts of tap water and severa2 portioc of distilled voter. Drain d4y

  18. Experimental evidence of beam-foil plasma creation during ion-solid interaction

    Science.gov (United States)

    Sharma, Prashant; Nandi, Tapan

    2016-08-01

    Charge state evolution of the energetic projectile ions during the passage through thin carbon foils has been revisited using the X-ray spectroscopy technique. Contributions from the bulk and the solid surface in the charge changing processes have been segregated by measuring the charge state distribution of the projectile ions in the bulk of the target during the ion-solid interaction. Interestingly, the charge state distribution measured in the bulk exhibits Lorentzian profile in contrast to the well-known Gaussian structure observed using the electromagnetic methods and the theoretical predictions. The occurrence of such behavior is a direct consequence of the imbalance between charge changing processes, which has been seen in various cases of the laboratory plasma. It suggests that the ion-solid collisions constitute high-density, localized plasma in the bulk of the solid target, called the beam-foil plasma. This condensed beam-foil plasma is similar to the high-density solar and stellar plasma which may have practical implementations in various fields, in particular, plasma physics and nuclear astrophysics. The present work suggests further modification in the theoretical charge state distribution calculations by incorporating the plasma coupling effects during the ion-solid interactions. Moreover, the multi-electron capture from the target exit surface has been confirmed through comparison between experimentally measured and theoretically predicted values of the mean charge state of the projectile ions.

  19. Total microcystins analysis in water using laser diode thermal desorption-atmospheric pressure chemical ionization-tandem mass spectrometry.

    Science.gov (United States)

    Roy-Lachapelle, Audrey; Fayad, Paul B; Sinotte, Marc; Deblois, Christian; Sauvé, Sébastien

    2014-04-11

    A new approach for the analysis of the cyanobacterial microcystins (MCs) in environmental water matrices has been developed. It offers a cost efficient alternative method for the fast quantification of total MCs using mass spectrometry. This approach permits the quantification of total MCs concentrations without requiring any derivatization or the use of a suite of MCs standards. The oxidation product 2-methyl-3-methoxy-4-phenylbutyric acid (MMPB) was formed through a Lemieux oxidation and represented the total concentration of free and bound MCs in water samples. MMPB was analyzed using laser diode thermal desorption-atmospheric pressure chemical ionization coupled to tandem mass spectrometry (LDTD-APCI-MS/MS). LDTD is a robust and reliable sample introduction method with ultra-fast analysis time (0.999). Limits of detection and quantification were 0.2 and 0.9 μg L(-1), respectively. These values are comparable with the WHO (World Health Organization) guideline of 1 μg L(-1) for total microcystin-LR congener in drinking water. Accuracy and interday/intraday variation coefficients were below 15%. Matrix effect was determined with a recovery of 91%, showing no significant signal suppression. This work demonstrates the use of the LDTD-APCI-MS/MS interface for the screening, detection and quantification of total MCs in complex environmental matrices.

  20. Thin-layer chromatography and mass spectrometry coupled using proximal probe thermal desorption with electrospray or atmospheric pressure chemical ionization.

    Science.gov (United States)

    Ovchinnikova, Olga S; Van Berkel, Gary J

    2010-06-30

    An atmospheric pressure proximal probe thermal desorption sampling method coupled with secondary ionization by electrospray or atmospheric pressure chemical ionization was demonstrated for the mass spectrometric analysis of a diverse set of compounds (dyestuffs, pharmaceuticals, explosives and pesticides) separated on various high-performance thin-layer chromatography plates. Line scans along or through development lanes on the plates were carried out by moving the plate relative to a stationary heated probe positioned close to or just touching the stationary phase surface. Vapors of the compounds thermally desorbed from the surface were drawn into the ionization region of a combined electrospray ionization/atmospheric pressure chemical ionization source where they merged with reagent ions and/or charged droplets from a corona discharge or an electrospray emitter and were ionized. The ionized components were then drawn through the atmospheric pressure sampling orifice into the vacuum region of a triple quadrupole mass spectrometer and detected using full scan, single ion monitoring, or selected reaction monitoring mode. Studies of variable parameters and performance metrics including the proximal probe temperature, gas flow rate into the ionization region, surface scan speed, read-out resolution, detection limits, and surface type are discussed.

  1. Leidenfrost phenomenon-assisted thermal desorption (LPTD) and its application to open ion sources at atmospheric pressure mass spectrometry.

    Science.gov (United States)

    Saha, Subhrakanti; Chen, Lee Chuin; Mandal, Mridul Kanti; Hiraoka, Kenzo

    2013-03-01

    This work describes the development and application of a new thermal desorption technique that makes use of the Leidenfrost phenomenon in open ion sources at atmospheric pressure for direct mass spectrometric detection of ultratrace levels of illicit, therapeutic, and stimulant drugs, toxicants, and peptides (molecular weight above 1 kDa) in their unaltered state from complex real world samples without or with minor sample pretreatment. A low temperature dielectric barrier discharge ion source was used throughout the experiments and the analytical figures of merit of this technique were investigated. Further, this desorption technique coupled with other ionization sources such as electrospray ionization (ESI) and dc corona discharge atmospheric pressure chemical ionization (APCI) in open atmosphere was also investigated. The use of the high-resolution 'Exactive Orbitrap' mass spectrometer provided unambiguous identification of trace levels of the targeted compounds from complex mixtures and background noise; the limits of detection for various small organic molecules and peptides treated with this technique were at the level of parts per trillion and 10(-9) M, respectively. The high sensitivity of the present technique is attributed to the spontaneous enrichment of analyte molecules during the slow evaporation of the solvent, as well as to the sequential desorption of molecules from complex mixtures based on their volatilities. This newly developed desorption technique is simple and fast, while molecular ions are observed as the major ions.

  2. Thermal desorption counter-flow introduction atmospheric pressure chemical ionization for direct mass spectrometry of ecstasy tablets.

    Science.gov (United States)

    Inoue, Hiroyuki; Hashimoto, Hiroaki; Watanabe, Susumu; Iwata, Yuko T; Kanamori, Tatsuyuki; Miyaguchi, Hajime; Tsujikawa, Kenji; Kuwayama, Kenji; Tachi, Noriyuki; Uetake, Naohito

    2009-09-01

    A novel approach to the analysis of ecstasy tablets by direct mass spectrometry coupled with thermal desorption (TD) and counter-flow introduction atmospheric pressure chemical ionization (CFI-APCI) is described. Analytes were thermally desorbed with a metal block heater and introduced to a CFI-APCI source with ambient air by a diaphragm pump. Water in the air was sufficient to act as the reactive reagent responsible for the generation of ions in the positive corona discharge. TD-CFI-APCI required neither a nebulizing gas nor solvent flow and the accompanying laborious optimizations. Ions generated were sent in the direction opposite to the air flow by an electric field and introduced into an ion trap mass spectrometer. The major ions corresponding to the protonated molecules ([M + H](+)) were observed with several fragment ions in full scan mass spectrometry (MS) mode. Collision-induced dissociation of protonated molecules gave characteristic product-ion mass spectra and provided identification of the analytes within 5 s. The method required neither sample pretreatment nor a chromatographic separation step. The effectiveness of the combination of TD and CFI-APCI was demonstrated by application to the direct mass spectrometric analysis of ecstasy tablets and legal pharmaceutical products.

  3. An Optimized Adsorbent Sampling Combined to Thermal Desorption GC-MS Method for Trimethylsilanol in Industrial Environments

    Directory of Open Access Journals (Sweden)

    Jae Hwan Lee

    2012-01-01

    Full Text Available Trimethylsilanol (TMSOH can cause damage to surfaces of scanner lenses in the semiconductor industry, and there is a critical need to measure and control airborne TMSOH concentrations. This study develops a thermal desorption (TD-gas chromatography (GC-mass spectrometry (MS method for measuring trace-level TMSOH in occupational indoor air. Laboratory method optimization obtained best performance when using dual-bed tube configuration (100 mg of Tenax TA followed by 100 mg of Carboxen 569, n-decane as a solvent, and a TD temperature of 300°C. The optimized method demonstrated high recovery (87%, satisfactory precision (<15% for spiked amounts exceeding 1 ng, good linearity (R2=0.9999, a wide dynamic mass range (up to 500 ng, low method detection limit (2.8 ng m−3 for a 20-L sample, and negligible losses for 3-4-day storage. The field study showed performance comparable to that in laboratory and yielded first measurements of TMSOH, ranging from 1.02 to 27.30 μg/m3, in the semiconductor industry. We suggested future development of real-time monitoring techniques for TMSOH and other siloxanes for better maintenance and control of scanner lens in semiconductor wafer manufacturing.

  4. Demonstration Testing of a Thermal Desorption Unit to Receive and Treat Waste with Unlimited Concentration of PCBs - 13437

    Energy Technology Data Exchange (ETDEWEB)

    Orton, Timothy L. [EnergySolutions, 423 West 300 South, Salt Lake City, UT 84101 (United States); Palmer, Carl R. [TD.X Associates LP, 148 South Dowlen Road, PMB 700, Beaumont, TX 77707 (United States)

    2013-07-01

    For the last nine years, EnergySolutions and TD*X Associates LP have teamed up to provide the most comprehensive organic removal treatment process in the radioactive waste industry. The high performance thermal desorption unit (HP-TDU) located at the EnergySolutions Clive facility in Utah has successfully processed over 1,850 tons of organically contaminated radioactive mixed waste. Products from the HP-TDU system include a radioactively contaminated dry solid material that can be disposed in the on-site landfill and an organic condensate with high thermal energy content that is generally below background radiation and capable of free-release to a non-radioactive incinerator. Over the years, Permits and approvals have been obtained through the state of Utah, United States Environmental Protection Agency (USEPA) Region 8, and USEPA headquarters that enable the treatment of several waste categories including volatile and semi-volatile organic compounds, combustion-coded (CMBST) compounds, volatile metals, and polychlorinated biphenyls (PCBs). The unit has recently successfully completed Demonstration Testing for PCB concentrations up to 660,000 ppm (parts per million). Solid processed material from this Demonstration Testing was less than two ppm PCBs in three separate treatment runs; reprocessing or additional treatment was not needed to meet this limit. Through post-demonstration permitting, the system is unlimited in scope as approval has been given to receive and solidify up to pure PCBs down to this processing limit concentration to complete treatment of mixed waste. (authors)

  5. MERCURY QUANTIFICATION IN SOILS USING THERMAL DESORPTION AND ATOMIC ABSORPTION SPECTROMETRY: PROPOSAL FOR AN ALTERNATIVE METHOD OF ANALYSIS

    Directory of Open Access Journals (Sweden)

    Liliane Catone Soares

    2015-08-01

    Full Text Available Despite the considerable environmental importance of mercury (Hg, given its high toxicity and ability to contaminate large areas via atmospheric deposition, little is known about its activity in soils, especially tropical soils, in comparison with other heavy metals. This lack of information about Hg arises because analytical methods for determination of Hg are more laborious and expensive compared to methods for other heavy metals. The situation is even more precarious regarding speciation of Hg in soils since sequential extraction methods are also inefficient for this metal. The aim of this paper is to present a technique of thermal desorption associated with atomic absorption spectrometry, TDAAS, as an efficient tool for quantitative determination of Hg in soils. The method consists of the release of Hg by heating, followed by its quantification by atomic absorption spectrometry. It was developed by constructing calibration curves in different soil samples based on increasing volumes of standard Hg2+ solutions. Performance, accuracy, precision, and quantification and detection limit parameters were evaluated. No matrix interference was detected. Certified reference samples and comparison with a Direct Mercury Analyzer, DMA (another highly recognized technique, were used in validation of the method, which proved to be accurate and precise.

  6. Coupling Laser Diode Thermal Desorption with Acoustic Sample Deposition to Improve Throughput of Mass Spectrometry-Based Screening.

    Science.gov (United States)

    Haarhoff, Zuzana; Wagner, Andrew; Picard, Pierre; Drexler, Dieter M; Zvyaga, Tatyana; Shou, Wilson

    2016-02-01

    The move toward label-free screening in drug discovery has increased the demand for mass spectrometry (MS)-based analysis. Here we investigated the approach of coupling acoustic sample deposition (ASD) with laser diode thermal desorption (LDTD)-tandem mass spectrometry (MS/MS). We assessed its use in a cytochrome P450 (CYP) inhibition assay, where a decrease in metabolite formation signifies CYP inhibition. Metabolite levels for 3 CYP isoforms were measured as CYP3A4-1'-OH-midazolam, CYP2D6-dextrorphan, and CYP2C9-4'-OH-diclofenac. After incubation, samples (100 nL) were acoustically deposited onto a stainless steel 384-LazWell plate, then desorbed by an infrared laser directly from the plate surface into the gas phase, ionized by atmospheric pressure chemical ionization (APCI), and analyzed by MS/MS. Using this method, we achieved a sample analysis speed of 2.14 s/well, with bioanalytical performance comparable to the current online solid-phase extraction (SPE)-based MS method. An even faster readout speed was achieved when postreaction sample multiplexing was applied, where three reaction samples, one for each CYP, were transferred into the same well of the LazWell plate. In summary, LDTD coupled with acoustic sample deposition and multiplexing significantly decreased analysis time to 0.7 s/sample, making this MS-based approach feasible to support high-throughput screening (HTS) assays.

  7. CREATION OF GRADIENT PLASMA-SPRAYED COATINGS ON BASIS OF ZIRCONIUM DIOXIDE STABILIZED WITH YTTERBIUM DIOXIDE

    Directory of Open Access Journals (Sweden)

    V. A. Okovity

    2011-01-01

    Full Text Available The process has been investigated and technological parameters for spraying gradient plasma coatings on the basis of zirconium dioxide stabilized with ytterbium dioxide have been optimized in the paper.

  8. Creation of hydrophilic nitric oxide releasing polymers via plasma surface modification.

    Science.gov (United States)

    Pegalajar-Jurado, A; Joslin, J M; Hawker, M J; Reynolds, M M; Fisher, E R

    2014-08-13

    Herein, we describe the surface modification of an S-nitrosated polymer derivative via H2O plasma treatment, resulting in polymer coatings that maintained their nitric oxide (NO) releasing capabilities, but exhibited dramatic changes in surface wettability. The poly(lactic-co-glycolic acid)-based hydrophobic polymer was nitrosated to achieve a material capable of releasing the therapeutic agent NO. The NO-loaded films were subjected to low-temperature H2O plasma treatments, where the treatment power (20-50 W) and time (1-5 min) were varied. The plasma treated polymer films were superhydrophilic (water droplet spread completely in plasma-treated materials; however, they still result in physiologically relevant NO fluxes. XPS, SEM-EDS, and ATR-IR characterization suggests the plasma treatment resulted in polymer rearrangement and implantation of hydroxyl and carbonyl functional groups. Plasma treated samples maintained both hydrophilic surface properties and NO release profiles after storage at -18 °C for at least 10 days, demonstrating the surface modification and NO release capabilities are stable over time. The ability to tune polymer surface properties while maintaining bulk properties and NO release properties, and the stability of those properties under refrigerated conditions, represents a unique approach toward creating enhanced therapeutic biopolymers.

  9. Plasma technology for creation of protective and decorative coatings for building materials

    Science.gov (United States)

    Volokitin, Oleg; Volokitin, Gennady; Skripnikova, Nelli; Shekhovtsov, Valentin

    2016-01-01

    An experimental setup is developed to create a protective and decorative coating on the surface of building materials. Experimental study is conducted to create a protective coating using low-temperature plasma. The properties of the surface before and after the plasma treatment are investigated. At the increase of the plasma generator power (56-75 kW) the rate of the vitreous coating formation is significantly reduced, and the destruction of hydrous calcium silicates occurs at a lower depth (0.5-2.0 mm). In this case, the adhesive strength increases up to 2.34 MPa. At the increase of the exposure time at 56 kW (0.045 m/s melting rate) plasma generation power, the melt formation is observed not only at the surface but at depth of 0.7 mm and deeper. Also, a deep degradation of the material occurs and the adhesive strength decreases. The optimal heat flux density of plasma generator was established at 1.8-2.6 . 106 W/m2, which allows the achievement of the uniform layer formation on the wood surface that preserves its natural pattern visible.

  10. Thermal desorption characterisation of molecularly imprinted polymers. Part II: Use of direct probe GC-MS analysis to study crosslinking effects.

    Science.gov (United States)

    Holland, Niamh; Duggan, Patrick; Owens, Eleanor; Cummins, Wayne; Frisby, June; Hughes, Helen; McLoughlin, Peter

    2008-06-01

    A powerful method utilising direct probe thermal desorption GC-MS is presented for the study of molecularly imprinted polymers (MIPs). A series of 2-aminopyridine (2-apy)-imprinted methacrylic acid-ethyleneglycol dimethacrylate (MAA-EGDMA) copolymers were prepared under identical conditions but with varying amounts of EGDMA (crosslinking monomer). The use of appropriate temperature programmes permitted template removal, and the subsequent assessment of polymer affinity and specificity, all of which were found to be dependent on polymer composition and morphology. The system was sufficiently sensitive to identify a specific response of imprinted polymers over nonimprinted counterparts. Correlations were found to exist between thermal desorption analysis and solution phase binding, which was assessed by UV spectroscopy, where specificity was found to diminish with decreasing EGDMA concentration. This was attributed to the increased number of free carboxyl groups in those polymers containing a lower percentage of EGDMA. Thermal desorption profiles obtained for the analyte were found to be unaffected by the physical and chemical properties of the solvent used for analyte reloading.

  11. Evaluation of two adsorbents for diffusive sampling and thermal desorption-gas chromatographic analysis of monoterpenes in air.

    Science.gov (United States)

    Sunesson, A L; Sundgren, M; Levin, J O; Eriksson, K; Carlson, R

    1999-02-01

    Tube type samplers with two different adsorbents, Chromosorb 106 and Tenax TA, were evaluated by laboratory experiments and field tests for simultaneous diffusive sampling of alpha-pinene, beta-pinene and delta 3-carene and subsequent thermal desorption-gas chromatographic analysis. No statistically significant effects of exposure time, concentrations of monoterpenes or relative humidity were found for samplers with Chromosorb 106 when running a factorial design, with the exception of the adsorption of delta 3-carene, for which some weak effects were noted. Samplers with Tenax TA were affected by the sampling time as well as the concentration for all terpenes, with a strong interaction effect between these two factors. The terpenes showed good storage stability on both adsorbents. No effect of back-diffusion was noted when using Chromosorb 106, while Tenax TA showed some back-diffusion effects. The uptake rates, in ml min-1, for the terpenes on Chromosorb 106 were 0.36 for alpha-pinene, 0.36 for beta-pinene and 0.40 for delta 3-carene. The corresponding average values on Tenax TA were 0.30 for alpha-pinene, 0.32 for beta-pinene and 0.38 for delta 3-carene. The field validation proved that diffusive sampling on Chromosorb 106 agreed well with pumped sampling on charcoal for stationary samples, while the personal samples indicated a discrepancy of 25% between Chromosorb 106 and charcoal samples. Tenax TA generally gave lower results than Chromosorb 106 in all field samples. Samplers packed with Chromosorb 106 could be used to monitor terpene levels in workplaces such as sawmills. The major advantages with this method are the sampling procedure, which is simple to perform compared to other techniques, the easily automated analysis procedure and the possibility to reuse the samplers.

  12. Thermal desorption gas chromatography and positron annihilation spectroscopy, contribution to alpha decay studies in actinide-doped matrices

    Energy Technology Data Exchange (ETDEWEB)

    Roudil, D.; Jegou, C.; Vella, F.; Folch, B.; Broudic, V. [Commissariat a l' energie Atomique, Rhone Valley Research Center, 30200 Bagnols-sur-Ceze (France); Pik, R. [CNRS-CRPG, 54506 Vandoeuvre-les-Nancy (France); Barthe, M. F. [CNRS-CEMHTI, 45071 Orleans (France); Cuney, M. [Universite de Nancy, CNRS, CREGU, 54506 Vandoeuvre-les-Nancy (France); Pipon, Y. [IPNL CNRS, IN2P3 UMR 5822, 69622 Villeurbanne (France)

    2009-07-01

    A thermal desorption system coupled with a gas analyzer has been adapted and nuclearized to investigate He behavior in actinide-doped samples used to simulate alpha decay aging. This technique widely used in standard laboratories allows measurements of the helium balance and reduced diffusion coefficients, and a preliminary evaluation of helium locations (related to defects and thermal annealing). In our system implemented in a hot cell, small samples are annealed at up to 1100 C degrees in controlled atmosphere. They are inserted in a 10 to 20 cm{sup 3} vessel connected to a micro gas chromatography detector. Initial system calibration allowed concentration measurements within about 10%. Comparisons with the CNRS/CRPG rare gas analysis laboratory at Nancy (France) were applied on natural uranium oxides originating from Oklo (Gabon) and Mistamisk (Canada). The latest results obtained on Mistamisk samples are in good agreement, with a maximum relative deviation of 14%. The data were used to determine the activation energy of about 1 eV.at{sup -1}. On (U,Pu)O{sub 2} and PuO{sub 2} samples the experiments highlight the impact of defects (up to 100 dpa) on He mobility. The defect population must now be characterized to improve our knowledge of He/defect interactions and mechanisms. In addition and synergy to the macroscopic release measurements by gas chromatography, positron annihilation spectroscopy, an effective nondestructive technique for vacancy defect investigation, was also developed and nuclearized in our hot cell laboratory as part of a project supported by the NOMADE and MATINEX research groups. Specific protocols for doped sample analysis were also developed and validated with UO{sub 2} and (U,Pu)O{sub 2} samples. (authors)

  13. Characterization of thermal desorption with the Deans-switch technique in gas chromatographic analysis of volatile organic compounds.

    Science.gov (United States)

    Ou-Yang, Chang-Feng; Huang, Ying-Xue; Huang, Ting-Jyun; Chen, Yong-Shen; Wang, Chieh-Heng; Wang, Jia-Lin

    2016-09-02

    This study presents a novel application based on the Deans-switch cutting technique to characterize the thermal-desorption (TD) properties for gas chromatographic (GC) analysis of ambient volatile organic compounds (VOCs). Flash-heating of the sorbent bed at high temperatures to desorb trapped VOCs to GC may easily produce severe asymmetric or tailing GC peaks affecting resolution and sensitivity if care is not taken to optimize the TD conditions. The TD peak without GC separation was first examined for the quality of the TD peak by analyzing a standard gas mixture from C2 to C12 at ppb level. The Deans switch was later applied in two different stages. First, it was used to cut the trailing tail of the TD peak, which, although significantly improved the GC peak symmetry, led to more loss of the higher boiling compounds than the low boiling ones, thus suggesting compound discrimination. Subsequently, the Deans switch was used to dissect the TD peak into six 30s slices in series, and an uneven distribution in composition between the slices were found. A progressive decrease in low boiling compounds and increase in higher boiling ones across the slices indicated severe inhomogeneity in the TD profile. This finding provided a clear evidence to answer the discrimination problem found with the tail cutting approach to improve peak symmetry. Through the use of the innovated slicing method based on the Deans-switch cutting technique, optimization of TD injection for highly resolved, symmetric and non-discriminated GC peaks can now be more quantitatively assessed and guided.

  14. The role of energetic ions from plasma in the creation of nanostructured materials and stable polymer surface treatments

    Energy Technology Data Exchange (ETDEWEB)

    Bilek, M.M.M. [Department of Applied and Plasma Physics, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia)]. E-mail: mmmb@physics.usyd.edu.au; Newton-McGee, K. [Department of Applied and Plasma Physics, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia); McKenzie, D.R. [Department of Applied and Plasma Physics, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia); McCulloch, D.G. [Department of Applied and Plasma Physics, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia)

    2006-01-15

    Plasma processes for the synthesis of new materials as thin films have enabled the production of a wide variety of new materials. These include meta-stable phases, which are not readily found in nature, and more recently, materials with structure on the nanoscale. Study of plasma synthesis processes at the fundamental level has revealed that ion energy, depositing flux and growth surface temperature are the critical parameters affecting the microstructure and the properties of the thin film materials formed. In this paper, we focus on the role of ion flux and impact energy in the creation of thin films with nanoscale structure in the form of multilayers. We describe three synthesis strategies, based on the extraction of ions from plasma sources and involving modulation of ion flux and ion energy. The microstructure, intrinsic stress and physical properties of the multilayered samples synthesized are studied and related back to the conditions at the growth surface during deposition. When energetic ions of a non-condensing species are used, it is possible to place active groups on the surfaces of materials such as polymers. These active groups can then be used as bonding sites in subsequent chemical attachment of proteins or other macromolecules. If the energy of the non-condensing ions is increased to a few keV then modified layers buried under the surface can be produced. Here we describe a method by which the aging effect, which is often observed in plasma surface modifications on polymers, can be reduced and even eliminated using high energy ion bombardment.

  15. First on-line positron experiments en route to pair-plasma creation

    Energy Technology Data Exchange (ETDEWEB)

    Stanja, Juliane; Hergenhahn, Uwe; Stenson, Eve V. [Max-Planck-Institut fuer Plasmaphysik (Germany); Niemann, Holger; Sunn Pedersen, Thomas [Max-Planck-Institut fuer Plasmaphysik (Germany); Ernst-Moritz-Arndt Universitaet Greifswald (Germany); Saitoh, Haruhiko [Max-Planck-Institut fuer Plasmaphysik (Germany); The University of Tokyo (Japan); Stoneking, Matthew R. [Lawrence University (United States); Hugenschmidt, Christoph; Piochacz, Christian [Technische Universitaet Muenchen (Germany); Schweikhard, Lutz [Ernst-Moritz-Arndt Universitaet Greifswald (Germany)

    2016-07-01

    Electron-positron plasmas are predicted to show a fundamentally different behavior from traditional ion-electron plasmas, because of the equal masses of the two species. Using up to 10{sup 9} positrons per second provided by the NEPOMUC (Neutron-Induced Positron Source Munich) facility, the APEX/PAX team aims to create the first such plasma confined in a toroidal magnetic trap. Positron beam parameters as well as efficient injection and confinement schemes for both species in toroidal geometries are fundamental to the project. In this contribution we present results from first on-line positron experiments. Besides characterizing the NEPOMUC beam we conducted positron injection experiments into a dipole magnetic field configuration. Using static electric fields, a 5-eV positron beam was transported across magnetic field lines into the confinement region. With this method, up to 38% of the incoming particles reach the confinement region and make at least a 180 revolution around the magnet. Under dedicated experimental conditions confinement on the order of 1 ms was realized.

  16. Creation and diagnosis of a solid-density plasma with an X-ray free-electron laser.

    Science.gov (United States)

    Vinko, S M; Ciricosta, O; Cho, B I; Engelhorn, K; Chung, H-K; Brown, C R D; Burian, T; Chalupský, J; Falcone, R W; Graves, C; Hájková, V; Higginbotham, A; Juha, L; Krzywinski, J; Lee, H J; Messerschmidt, M; Murphy, C D; Ping, Y; Scherz, A; Schlotter, W; Toleikis, S; Turner, J J; Vysin, L; Wang, T; Wu, B; Zastrau, U; Zhu, D; Lee, R W; Heimann, P A; Nagler, B; Wark, J S

    2012-01-25

    Matter with a high energy density (>10(5) joules per cm(3)) is prevalent throughout the Universe, being present in all types of stars and towards the centre of the giant planets; it is also relevant for inertial confinement fusion. Its thermodynamic and transport properties are challenging to measure, requiring the creation of sufficiently long-lived samples at homogeneous temperatures and densities. With the advent of the Linac Coherent Light Source (LCLS) X-ray laser, high-intensity radiation (>10(17) watts per cm(2), previously the domain of optical lasers) can be produced at X-ray wavelengths. The interaction of single atoms with such intense X-rays has recently been investigated. An understanding of the contrasting case of intense X-ray interaction with dense systems is important from a fundamental viewpoint and for applications. Here we report the experimental creation of a solid-density plasma at temperatures in excess of 10(6) kelvin on inertial-confinement timescales using an X-ray free-electron laser. We discuss the pertinent physics of the intense X-ray-matter interactions, and illustrate the importance of electron-ion collisions. Detailed simulations of the interaction process conducted with a radiative-collisional code show good qualitative agreement with the experimental results. We obtain insights into the evolution of the charge state distribution of the system, the electron density and temperature, and the timescales of collisional processes. Our results should inform future high-intensity X-ray experiments involving dense samples, such as X-ray diffractive imaging of biological systems, material science investigations, and the study of matter in extreme conditions.

  17. Thermal desorption GC-MS as a tool to provide PAH certified standard reference material on particulate matter quartz filters.

    Science.gov (United States)

    Grandesso, Emanuela; Pérez Ballesta, Pascual; Kowalewski, Konrad

    2013-02-15

    Reference materials for particulate matter (PM) on filter media are not available for the quantification of polycyclic aromatic hydrocarbons (PAHs) in ambient air. This is due to the difficulty of obtaining reference material that has a homogeneous distribution on a filter surface that is large enough for characterization and distribution. High volume sample filters from different locations and seasons were considered to validate the feasibility of the use of quartz filters as reference material for PAH concentrations. A rapid thermal desorption (TD) technique coupled with gas chromatography/mass spectroscopy was applied to characterise the material for the content of fifteen different PAHs. TD technique allowed for rapid and accurate analysis of small sections of filter (5mm diameter), leaving enough material for the production of twenty sub-filter cuts (42 mm diameter) that could be used for distribution and control. Stability and homogeneity tests required for material certification were performed as indicated by the ISO guide 34:2009 and ISO 35:2006. The contribution of the heterogeneous distribution of PAHs on the filter surface resulted generally lower than 10% and higher for more volatile PAHs. One year of storage at -18°C indicated no significant variation in PAH concentrations. Nevertheless, a methodology for shipping and storing of the filter material at ambient temperature in especially designed plastic envelopes, was also shown to allow for stabile concentrations within twenty days. The method accuracy was confirmed by the analysis of NIST SRM 1649a (urban dust) and PAH concentrations were validated against the reference values obtained from an inter-laboratory exercise. In the case of benzo[a]pyrene for masses quantified between 100 pg and 10 ng the TD method provided expanded uncertainties of circa 10%, while the inter-laboratory reference value uncertainties ranged between 15 and 20%. The evaluation of these results supports the use of the presented

  18. Hydrogen sulphide in human nasal air quantified using thermal desorption and selected ion flow tube mass spectrometry.

    Science.gov (United States)

    Wondimu, Taddese; Wang, Rui; Ross, Brian

    2014-09-01

    The discovery that hydrogen sulphide (H2S) acts as a gasotransmitter when present at very low concentrations (sub-parts per billion (ppbv)) has resulted in the need to quickly quantify trace amounts of the gas in complex biological samples. Selected ion flow tube mass spectrometry (SIFT-MS) is capable of real-time quantification of H2S but many SIFT-MS instruments lack sufficient sensitivity for this application. In this study we investigate the utility of combining thermal desorption with SIFT-MS for quantifying H2S in the 0.1-1 ppbv concentration range. Human orally or nasally derived breath, and background ambient air, were collected in sampling bags and dried by passing through CaCl2 and H2S pre-concentrated using a sorbent trap optimised for the capture of this gas. The absorbed H2S was then thermally desorbed and quantified by SIFT-MS. H2S concentrations in ambient air, nasal breath and oral breath collected from 10 healthy volunteers were 0.12  ±  0.02 (mean ± SD), 0.40  ±  0.11 and 3.1  ±  2.5 ppbv respectively, and in the oral cavity H2S, quantified by SIFT-MS without pre-concentration, was present at 13.5  ±  8.6 ppbv. The oral cavity H2S correlates well with oral breath H2S but not with nasal breath H2S, suggesting that oral breath H2S derives mainly from the oral cavity but nasal breath is likely pulmonary in origin. The successful quantification of such low concentrations of H2S in nasal air using a rapid analytical procedure paves the way for the straightforward analysis of H2S in breath and may assist in elucidating the role that H2S plays in biological systems.

  19. Comparison of two common adsorption materials for thermal desorption gas chromatography - mass spectrometry of biogenic volatile organic compounds.

    Science.gov (United States)

    Marcillo, Andrea; Jakimovska, Viktorija; Widdig, Anja; Birkemeyer, Claudia

    2017-09-08

    Volatile organic compounds (VOCs) are commonly collected from gaseous samples by adsorption to materials such as the porous polymer Tenax TA. Adsorbed compounds are subsequently released from these materials by thermal desorption (TD) and separated then by gas chromatography (GC) with flame ionization (FID) or mass spectrometry (MS) detection. Tenax TA is known to be particularly suitable for non-polar to semipolar volatiles, however, many volatiles from environmental and biological samples possess a rather polar character. Therefore, we tested if the polymer XAD-2, which so far is widely used to adsorb organic compounds from aqueous and organic solvents, could provide a broader coverage for (semi)polar VOCs during gas-phase sampling. Mixtures of volatile compounds covering a wide range of volatility (bp. 20-256°C) and different chemical classes were introduced by liquid spiking into sorbent tubes with one of the two porous polymers, Tenax TA or XAD-2, and analyzed by TD/GC-MS. At first, an internal standard mixture composed of 17 authentic standards was used to optimize desorption temperature with respect to sorbent degradation and loading time for calibration. Secondly, we tested the detectability of a complex standard mixture composed of 57 volatiles, most of them common constituents of the body odor of mammals. Moreover, the performance of XAD-2 compared with Tenax TA was assessed as limit of quantitation and linearity for the internal standard mixture and 33 compounds from the complex standard mixture. Volatiles were analyzed in a range between 0.01-∼250ng/tube depending on the compound and material. Lower limits of quantitation were between 0.01 and 3 ng±0.9). Interestingly, we found different kinetics for compound adsorption with XAD-2, and a partially better sensitivity in comparison with Tenax TA. For these analytes, XAD-2 might be recommended as an alternative of Tenax TA for TD/GC-MS analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Creation of a homogeneous plasma column by means of hohlraum radiation for ion-stopping measurements

    CERN Document Server

    Faik, Steffen; Basko, Mikhail M; Maruhn, Joachim A; Rosmej, Olga; Rienecker, Tim; Novikov, Vladimir G; Grushin, Alexander S

    2014-01-01

    In this work, we present the results of two-dimensional radiation-hydrodynamics simulations of a hohlraum target whose outgoing radiation is used to produce a homogeneously ionized carbon plasma for ion-beam stopping measurements. The cylindrical hohlraum with gold walls is heated by a frequency-doubled (\\lambda_l = 526.5 \\mu m) 1.4 ns long laser pulse with the total energy of E_l = 180 J. At the laser spot, the peak matter and radiation temperatures of, respectively, T ~ 380 eV and T_r ~ 120 eV are observed. X-rays from the hohlraum heat the attached carbon foam with a mean density of \\rho_C = 2 mg/cm^3 to a temperature of T ~ 25 eV. The simulation shows that the carbon ionization degree (Z ~ 3.75) and its column density stay relatively stable (within variations of about +-7%) long enough to conduct the ion-stopping measurements. Also, it is found that a special attention should be paid to the shock wave, emerging from the x-ray heated copper support plate, which at later times may significantly distort the ...

  1. Low-flow active and passive sampling of VOCs using thermal desorption tubes: theory and application at an offset printing facility.

    Science.gov (United States)

    Batterman, Stuart; Metts, Tricia; Kalliokoski, Pentti; Barnett, Emily

    2002-06-01

    While air sampling techniques using adsorbent-based collection, thermal desorption and chromatographic analysis have found a niche in ambient air sampling, occupational applications have been more limited. This paper evaluates the use of thermal desorption techniques for low flow active and passive sampling configurations which allow conveniently long duration sampling in occupational settings and other high concentration environments. The use of an orifice enables flows as low as 0.5 ml min(-1) and sampling periods up to several days without significant biases. A model is used to predict sampling rates of a passive sampler encompassing an orifice, a void space, glass wool, and the adsorbent. Laboratory and field tests conducted at a commercial offset printing facility, which contained a variety of volatile organic compounds (primarily aromatic but also a few chlorinated and terpene compounds at levels from 1 to 67,000 microg m(-3)), are used to evaluate the approach. Tenax GR and Carbosieve SIII, both singly and together, were employed as adsorbents. Side-by-side tests comparing high flow, low flow and passive samplers show excellent agreement and high linearity (r = 0.95) for concentrations spanning nearly five orders of magnitude. Active samplers were tested at flows as low as 0.5 ml min(-1), compared to typical flows up to 40 ml min(-1). Passive samplers demonstrated a linear range and agreement with predictions for adsorbate loadings from approximately 1 ng to nearly 10 microg. Using a chemical mass balance receptor model, concentrations in the facility were apportioned to solvents, inks and other indoor and outdoor sources. Overall, the use of low flow active and passive sampling approaches employing thermal desorption techniques provides good performance and tremendous flexibility that facilitates use in many applications, including workplace settings.

  2. Thermal decomposition of AlH{sub 3} studied by in situ synchrotron X-ray diffraction and thermal desorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Maehlen, J.P. [Institute for Energy Technology, P.O. Box 40, Kjeller No-2027 (Norway); Yartys, V.A. [Institute for Energy Technology, P.O. Box 40, Kjeller No-2027 (Norway)], E-mail: volodymyr.yartys@ife.no; Denys, R.V. [Institute for Energy Technology, P.O. Box 40, Kjeller No-2027 (Norway); Physico-Mechanical Institute of the National Academy of Science of Ukraine, 5, Naukova Str., 79601 Lviv (Ukraine); Fichtner, M.; Frommen, Ch. [Institute of Nanotechnology, Forschungszentrum Karlsruhe GmbH, P.O. Box 30640, D-76021 Karlsruhe (Germany); Bulychev, B.M. [Chemistry Department, Moscow State University, Leninskie Gori, Moscow 119992, MSU, Chemistry Department (Russian Federation); Pattison, P.; Emerich, H.; Filinchuk, Y.E.; Chernyshov, D. [Swiss-Norwegian Beam Line, ESRF, BP 220, F-38043 Grenoble (France)

    2007-10-31

    The thermal decomposition of alane was investigated by application of synchrotron X-ray diffraction (SR-XRD) and thermal desorption spectroscopy (TDS). Two polymorphs were studied, {alpha}- and {gamma}-AlH{sub 3}. Activation energies, anisotropic volume expansions, and phase transformation paths were found. In addition, the crystal structure data, including structure of hydrogen sublattice, and small charge transfer from the aluminium towards the hydrogen sites were observed during a high-resolution SR-XRD study of {alpha}-AlH{sub 3}.

  3. Ultra high vacuum high precision low background setup with temperature control for thermal desorption mass spectroscopy (TDA-MS) of hydrogen in metals.

    Science.gov (United States)

    Merzlikin, Sergiy V; Borodin, S; Vogel, D; Rohwerder, M

    2015-05-01

    In this work, a newly developed UHV-based high precision low background setup for hydrogen thermal desorption analysis (TDA) of metallic samples is presented. Using an infrared heating with a low thermal capacity enables a precise control of the temperature and rapid cool down of the measurement chamber. This novel TDA-set up is superior in sensitivity to almost every standard hydrogen analyzer available commercially due to the special design of the measurement chamber, resulting in a very low hydrogen background. No effects of background drift characteristic as for carrier gas based TDA instruments were observed, ensuring linearity and reproducibility of the analysis. This setup will prove to be valuable for detailed investigations of hydrogen trapping sites in steels and other alloys. With a determined limit of detection of 5.9×10(-3)µg g(-1) hydrogen the developed instrument is able to determine extremely low hydrogen amounts even at very low hydrogen desorption rates. This work clearly demonstrates the great potential of ultra-high vacuum thermal desorption mass spectroscopy instrumentation.

  4. Application of GC-MS with a SPME and thermal desorption technique for determination of dimethylamine and trimethylamine in gaseous samples for medical diagnostic purposes.

    Science.gov (United States)

    Wzorek, Beata; Mochalski, Paweł; Sliwka, Ireneusz; Amann, Anton

    2010-06-01

    Biogenic amines are interesting compounds which may be of use for medical diagnosis or therapeutic monitoring. The present paper deals with the problems that occur with concentration determination of dimethylamine (DMA) and trimethylamine (TMA). These occur in the breath of people suffering from renal disease. The measurement of amines present in trace concentrations requires the application of suitable analytical methods during sampling, storage and preconcentration. This is particularly so due to their polar and basic properties. In this paper, the application of solid phase microextraction (SPME) and thermal desorption (TD) with subsequent measurement by GC-MS for the determination of amines is discussed. For DMA, preconcentration by SPME did not give satisfactory results. TMA may be analysed using SPME preconcentration with an LOD of 1.5 ppb. Thermal desorption with Tenax as the adsorbing material allows reliable concentration determination for TMA (LOD = 0.5 ppb) and DMA (LOD = 4.6 ppb). DMA cannot be stored reliably in Tedlar bags and longer storage on Tenax (with subsequent TD) does not give good repeatability of results. For TMA, storage can be done on Tenax or in bags, the best results for the latter being achieved with Flex Foil bags.

  5. In situ ionic liquid dispersive liquid-liquid microextraction and direct microvial insert thermal desorption for gas chromatographic determination of bisphenol compounds.

    Science.gov (United States)

    Cacho, Juan Ignacio; Campillo, Natalia; Viñas, Pilar; Hernández-Córdoba, Manuel

    2016-01-01

    A new procedure based on direct insert microvial thermal desorption injection allows the direct analysis of ionic liquid extracts by gas chromatography and mass spectrometry (GC-MS). For this purpose, an in situ ionic liquid dispersive liquid-liquid microextraction (in situ IL DLLME) has been developed for the quantification of bisphenol A (BPA), bisphenol Z (BPZ) and bisphenol F (BPF). Different parameters affecting the extraction efficiency of the microextraction technique and the thermal desorption step were studied. The optimized procedure, determining the analytes as acetyl derivatives, provided detection limits of 26, 18 and 19 ng L(-1) for BPA, BPZ and BPF, respectively. The release of the three analytes from plastic containers was monitored using this newly developed analytical method. Analysis of the migration test solutions for 15 different plastic containers in daily use identified the presence of the analytes at concentrations ranging between 0.07 and 37 μg L(-1) in six of the samples studied, BPA being the most commonly found and at higher concentrations than the other analytes.

  6. Measurement of toxic volatile organic compounds in indoor air of semiconductor foundries using multisorbent adsorption/thermal desorption coupled with gas chromatography-mass spectrometry.

    Science.gov (United States)

    Wu, Chien-Hou; Lin, Ming-Nan; Feng, Chien-Tai; Yang, Kuang-Ling; Lo, Yu-Shiu; Lo, Jiunn-Guang

    2003-05-09

    A method for the qualitative and quantitative analysis of volatile organic compounds (VOCs) in the air of class-100 clean rooms at semiconductor fabrication facilities was developed. Air samples from two semiconductor factories were collected each hour on multisorbent tubes (including Carbopack B, Carbopack C, and Carbosieve SIII) with a 24-h automatic active sampling system and analyzed using adsorption/thermal desorption coupled with gas chromatography-mass spectrometry. Experimental parameters, including thermal desorption temperature, desorption time, and cryofocusing temperature, were optimized. The average recoveries and the method detection limits for the target compounds were in the range 94-101% and 0.31-0.89 ppb, respectively, under the conditions of a 1 L sampling volume and 80% relative humidity. VOCs such as acetone, isopropyl alcohol, 2-heptanone, and toluene, which are commonly used in the semiconductor and electronics industries, were detected and accurately quantified with the established method. Temporal variations of the analyte concentrations observed were attributed to the improper use of organic solvents during operation.

  7. Critical role of a pre-purge setup in the thermal desorption analysis of volatile organic compounds by gas chromatography with mass spectrometry.

    Science.gov (United States)

    Kim, Yong-Hyun; Kim, Ki-Hyun

    2015-07-01

    In general, volatile organic compounds in ambient air are quantified by following a well-defined standard calibration procedure using a gas-/liquid-phase standard. If the liquid standard is analyzed by a thermal desorption, the solvent effect is unavoidable through the alteration of breakthrough properties or retention times. To learn more about the variables of the thermal desorption-based analysis, the effect of pre-purge conditions was evaluated for 18 volatile organic compounds with different types of sorbent tube materials by fixing standard volume (1 μL) and flow rate (100 mL/min). The gas phase calibration was also carried out as reference for the non-solvent effect. A single tube filled with Tenax TA exhibited the least solvent effect with the short pre-purge (1 min), while being subject to the breakthrough at or above 10 min pre-purge. For a three-bed sorbent tube with Carboxen 1000, at least 10 min of pre-purge was needed for the compounds with a retention time close to methanol (e.g., propanal). Another three-bed tube with Carbopack X reduced the solvent effect efficiently for a short pre-purge (2 min) without the breakthrough. As such, the solvent effect can be adjusted by the proper control of the sorbent tube application.

  8. Combined Atomic Force Microscope-Based Topographical Imaging and Nanometer Scale Resolved Proximal Probe Thermal Desorption/Electrospray Ionization-Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Ovchinnikova, Olga S [ORNL; Nikiforov, Maxim [ORNL; Bradshaw, James A [ORNL; Jesse, Stephen [ORNL; Van Berkel, Gary J [ORNL

    2011-01-01

    Nanometer scale proximal probe thermal desorption/electrospray ionization mass spectrometry (TD/ESI-MS) was demonstrated for molecular surface sampling of caffeine from a thin film using a 30 nm diameter nano-thermal analysis (nano-TA) probe tip in an atomic force microscope (AFM) coupled via a vapor transfer line and ESI interface to a MS detection platform. Using a probe temperature of 350 C and a spot sampling time of 30 s, conical desorption craters 250 nm in diameter and 100 nm deep were created as shown through subsequent topographical imaging of the surface within the same system. Automated sampling of a 5 x 2 array of spots, with 2 m spacing between spots, and real time selective detection of the desorbed caffeine using tandem mass spectrometry was also demonstrated. Estimated from the crater volume (~2x106 nm3), only about 10 amol (2 fg) of caffeine was liberated from each thermal desorption crater in the thin film. These results illustrate a relatively simple experimental setup and means to acquire in automated fashion sub-micrometer scale spatial sampling resolution and mass spectral detection of materials amenable to TD. The ability to achieve MS-based chemical imaging with 250 nm scale spatial resolution with this system is anticipated.

  9. Use of thermal desorption gas chromatography-olfactometry/mass spectrometry for the comparison of identified and unidentified odor active compounds emitted from building products containing linseed oil

    DEFF Research Database (Denmark)

    Clausen, P. A.; Knudsen, Henrik Nellemose; Larsen, K.

    2008-01-01

    The emission of odor active volatile organic compounds (VOCs) from a floor oil based on linseed oil, the linseed oil itself and a low-odor linseed oil was investigated by thermal desorption gas chromatography combined with olfactometry and mass spectrometry (TD-GC-O/MS). The oils were applied...... identified by GC-MS. While 92 VOCs were detected from the oil used in the floor oil, only 13 were detected in the low-odor linseed oil. The major odor active VOCs were aldehydes and carboxylic acids. Spearmen rank correlation of the GC-O profiles showed that the odor profile of the linseed oil likely...... influenced the odor profile of the floor oil based on this linseed oil....

  10. Comparative study of thermal desorption and solvent extraction-gas chromatography-mass spectrometric analysis for the quantification of phthalates in polymers.

    Science.gov (United States)

    Kim, Jae Woo; Kim, Young-Min; Moon, Hye Mi; Hosaka, Akihiko; Watanabe, Chuichi; Teramae, Norio; Choe, Eun Kyung; Myung, Seung-Woon

    2016-06-17

    For the quantitative analysis of phthalates in polymers, a thermal desorption (TD)-GC-MS method was compared with solvent extraction (SE)-GC-MS methods which require the long pretreatment procedures using large amount of harmful organic solvents. Calibration curves of TD-GC-MS showed good linearity (r(2)>0.9997) and low method detection limit (phthalate polymer samples (test PTPSs) showed an RSD below 7.4% and acceptable recoveries (78.3-117.4%) as in the standard method of International Electrotechnical Commission. Even in a sample with a high concentration of phthalates (PTPS #3), the method also showed good recovery with low RSD values. The TD-GC-MS results were comparable with those results by SE-GC-MS methods, indicating that TD-GC-MS method also can be used for the quantification of phthalates in polymers. The average recovery (92-103%) and RSD (phthalates in polymers.

  11. Direct thermal desorption in the analysis of cheese volatiles by gas chromatography and gas chromatography-mass spectrometry: comparison with simultaneous distillation-extraction and dynamic headspace.

    Science.gov (United States)

    Valero, E; Sanz, J; Martínez-Castro, I

    2001-06-01

    Direct thermal desorption (DTD) has been used as a technique for extracting volatile components of cheese as a preliminary step to their gas chromatographic (GC) analysis. In this study, it is applied to different cheese varieties: Camembert, blue, Chaumes, and La Serena. Volatiles are also extracted using other techniques such as simultaneous distillation-extraction and dynamic headspace. Separation and identification of the cheese components are carried out by GC-mass spectrometry. Approximately 100 compounds are detected in the examined cheeses. The described results show that DTD is fast, simple, and easy to automate; requires only a small amount of sample (approximately 50 mg); and affords quantitative information about the main groups of compounds present in cheeses.

  12. Use of thermal desorption gas chromatography-olfactometry/mass spectrometry for the comparison of identified and unidentified odor active compounds emitted from building products containing linseed oil

    DEFF Research Database (Denmark)

    Clausen, P. A.; Knudsen, Henrik Nellemose; Larsen, K.

    2008-01-01

    The emission of odor active volatile organic compounds (VOCs) from a floor oil based on linseed oil, the linseed oil itself and a low-odor linseed oil was investigated by thermal desorption gas chromatography combined with olfactometry and mass spectrometry (TD-GC-O/MS). The oils were applied...... identified by GC-MS. While 92 VOCs were detected from the oil used in the floor oil, only 13 were detected in the low-odor linseed oil. The major odor active VOCs were aldehydes and carboxylic acids. Spearmen rank correlation of the GC-O profiles showed that the odor profile of the linseed oil likely...... influenced the odor profile of the floor oil based on this linseed oil....

  13. On-line derivatization for hourly measurements of gas- and particle-phase Semi-Volatile oxygenated organic compounds by Thermal desorption Aerosol Gas chromatography (SV-TAG

    Directory of Open Access Journals (Sweden)

    G. Isaacman

    2014-07-01

    Full Text Available Laboratory oxidation studies have identified a large number of oxygenated organic compounds that can be used as tracers to understand sources and oxidation chemistry of atmospheric particulate matter. Quantification of these compounds in ambient environments has traditionally relied on low time-resolution collection of filter samples followed by offline sample treatment with a derivatizing agent to allow analysis by gas chromatography of otherwise non-elutable organic chemicals with hydroxyl groups. We present here an automated in situ instrument for the measurement of highly polar organic semi-volatile and low-volatility compounds in both the gas- and particle-phase with hourly time-resolution. The dual-cell Semi-Volatile Thermal desorption Aerosol Gas chromatograph (SV-TAG with derivatization collects particle-only and combined particle-plus-vapor samples on two parallel sampling cells that are analyzed in series by thermal desorption into helium saturated with derivatizing agent. Introduction of MSTFA, a silylating agent, yields complete derivatization of all tested compounds, including alkanoic acids, polyols, diacids, sugars, and multifunctional compounds. In laboratory tests, derivatization is found to be highly reproducible (< 3% variability. During field deployment, a regularly injected internal standard is used to correct for variability in detector response, derivatization efficiency, desorption efficiency, and transfer efficiency. Error in quantification from instrument fluctuations is found to be less than 10% for hydrocarbons and less than 15% for all oxygenates for which a functionally similar internal standard is available. After internal standard corrections, calibration curves are found to be linear for all compounds over the span of one month with comparable response on both of the parallel sampling cells.

  14. Measurement of Passive Uptake Rates for Volatile Organic Compounds on Commercial Thermal Desorption Tubes and the Effect of Ozone on Sampling

    Energy Technology Data Exchange (ETDEWEB)

    Maddalena, Randy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Parra, Amanda [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Russell, Marion [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lee, Wen-Yee [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2013-05-01

    Diffusive or passive sampling methods using commercially filled axial-sampling thermal desorption tubes are widely used for measuring volatile organic compounds (VOCs) in air. The passive sampling method provides a robust, cost effective way to measure air quality with time-averaged concentrations spanning up to a week or more. Sampling rates for VOCs can be calculated using tube geometry and Fick’s Law for ideal diffusion behavior or measured experimentally. There is evidence that uptake rates deviate from ideal and may not be constant over time. Therefore, experimentally measured sampling rates are preferred. In this project, a calibration chamber with a continuous stirred tank reactor design and constant VOC source was combined with active sampling to generate a controlled dynamic calibration environment for passive samplers. The chamber air was augmented with a continuous source of 45 VOCs ranging from pentane to diethyl phthalate representing a variety of chemical classes and physiochemical properties. Both passive and active samples were collected on commercially filled Tenax TA thermal desorption tubes over an 11-day period and used to calculate passive sampling rates. A second experiment was designed to determine the impact of ozone on passive sampling by using the calibration chamber to passively load five terpenes on a set of Tenax tubes and then exposing the tubes to different ozone environments with and without ozone scrubbers attached to the tube inlet. During the sampling rate experiment, the measured diffusive uptake was constant for up to seven days for most of the VOCs tested but deviated from linearity for some of the more volatile compounds between seven and eleven days. In the ozone experiment, both exposed and unexposed tubes showed a similar decline in terpene mass over time indicating back diffusion when uncapped tubes were transferred to a clean environment but there was no indication of significant loss by ozone reaction.

  15. Dispersive micro solid-phase extraction for the rapid analysis of synthetic polycyclic musks using thermal desorption gas chromatography-mass spectrometry.

    Science.gov (United States)

    Chung, Wu-Hsun; Tzing, Shin-Hwa; Ding, Wang-Hsien

    2013-09-13

    A simple and solvent-free method for the rapid analysis of five synthetic polycyclic musks in water samples is described. The method involves the use of dispersive micro solid-phase extraction (D-μ-SPE) coupled with direct thermal desorption (TD) gas chromatography-mass spectrometry (GC-MS) operating in the selected-ion-storage (SIS) mode. The parameters affecting the extraction efficiency of the target analytes from water sample and the thermal desorption conditions in the GC injection-port were optimized using a central composite design method. The optimal extraction conditions involved immersing 3.2mg of a typical octadecyl (C18) bonded silica adsorbent (i.e., ENVI-18) in a 10mL water sample. After extraction by vigorously shaking for 1.0min, the adsorbents were collected and dried on a filter. The adsorbents were transferred to a micro-vial, which was directly inserted into GC temperature-programmed injector, and the extracted target analytes were then thermally desorbed in the GC injection-port at 337°C for 3.8min. The limits of quantitation (LOQs) were determined to be 1.2-3.0ng/L. Precision, as indicated by relative standard deviations (RSDs), was less than 9% for both intra- and inter-day analysis. Accuracy, expressed as the mean extraction recovery, was between 74 and 90%. A preliminary analysis of the river water samples revealed that galaxolide (HHCB) and tonalide (AHTN) were the two most common synthetic polycyclic musks present. Using a standard addition method, their concentrations were determined to in the range from 11 to 140ng/L.

  16. Online derivatization for hourly measurements of gas- and particle-phase semi-volatile oxygenated organic compounds by thermal desorption aerosol gas chromatography (SV-TAG)

    Science.gov (United States)

    Isaacman, G.; Kreisberg, N. M.; Yee, L. D.; Worton, D. R.; Chan, A. W. H.; Moss, J. A.; Hering, S. V.; Goldstein, A. H.

    2014-12-01

    Laboratory oxidation studies have identified a large number of oxygenated organic compounds that can be used as tracers to understand sources and oxidation chemistry of atmospheric particulate matter. Quantification of these compounds in ambient environments has traditionally relied on low-time-resolution collection of filter samples followed by offline sample treatment with a derivatizing agent to allow analysis by gas chromatography of otherwise non-elutable organic chemicals with hydroxyl groups. We present here an automated in situ instrument for the measurement of highly polar organic semi-volatile and low-volatility compounds in both the gas- and particle-phase with hourly quantification of mass concentrations and gas-particle partitioning. The dual-cell semi-volatile thermal desorption aerosol gas chromatograph (SV-TAG) with derivatization collects particle-only and combined particle-plus-vapor samples on two parallel sampling cells that are analyzed in series by thermal desorption into helium saturated with derivatizing agent. Introduction of MSTFA (N-methyl-N-(trimethylsilyl)trifluoroacetamide), a silylating agent, yields complete derivatization of all tested compounds, including alkanoic acids, polyols, diacids, sugars, and multifunctional compounds. In laboratory tests, derivatization is found to be highly reproducible (regularly injected internal standard is used to correct for variability in detector response, consumption of the derivatization agent, desorption efficiency, and transfer losses. Error in quantification from instrument fluctuations is found to be less than 10% for hydrocarbons and less than 15% for all oxygenates for which a functionally similar internal standard is available, with an uncertainty of 20-25% in measurements of particle fraction. After internal standard corrections, calibration curves are found to be linear for all compounds over the span of 1 month, with comparable response on both of the parallel sampling cells.

  17. On-line derivatization for hourly measurements of gas- and particle-phase Semi-Volatile oxygenated organic compounds by Thermal desorption Aerosol Gas chromatography (SV-TAG)

    Science.gov (United States)

    Isaacman, G.; Kreisberg, N. M.; Yee, L. D.; Worton, D. R.; Chan, A. W. H.; Moss, J. A.; Hering, S. V.; Goldstein, A. H.

    2014-07-01

    Laboratory oxidation studies have identified a large number of oxygenated organic compounds that can be used as tracers to understand sources and oxidation chemistry of atmospheric particulate matter. Quantification of these compounds in ambient environments has traditionally relied on low time-resolution collection of filter samples followed by offline sample treatment with a derivatizing agent to allow analysis by gas chromatography of otherwise non-elutable organic chemicals with hydroxyl groups. We present here an automated in situ instrument for the measurement of highly polar organic semi-volatile and low-volatility compounds in both the gas- and particle-phase with hourly time-resolution. The dual-cell Semi-Volatile Thermal desorption Aerosol Gas chromatograph (SV-TAG) with derivatization collects particle-only and combined particle-plus-vapor samples on two parallel sampling cells that are analyzed in series by thermal desorption into helium saturated with derivatizing agent. Introduction of MSTFA, a silylating agent, yields complete derivatization of all tested compounds, including alkanoic acids, polyols, diacids, sugars, and multifunctional compounds. In laboratory tests, derivatization is found to be highly reproducible (regularly injected internal standard is used to correct for variability in detector response, derivatization efficiency, desorption efficiency, and transfer efficiency. Error in quantification from instrument fluctuations is found to be less than 10% for hydrocarbons and less than 15% for all oxygenates for which a functionally similar internal standard is available. After internal standard corrections, calibration curves are found to be linear for all compounds over the span of one month with comparable response on both of the parallel sampling cells.

  18. Analysis of the chemical composition of organic aerosol at the Mt. Sonnblick observatory using a novel high mass resolution thermal-desorption proton-transfer-reaction mass-spectrometer (hr-TD-PTR-MS)

    NARCIS (Netherlands)

    Holzinger, R.|info:eu-repo/dai/nl/337989338; Kasper-Giebl, A.; Staudinger, M.; Schauer, G.; Roeckmann, T.|info:eu-repo/dai/nl/304838233

    2010-01-01

    For the first time a high mass resolution thermal desorption proton transfer reaction mass spectrometer (hr-TD-PTR-MS) was deployed in the field to analyze the composition of the organic fraction of aerosols. We report on measurements from the remote Mt. Sonnblick observatory in the Austrian alps

  19. Is the existence of a softest point in the directed flow excitation function an unambiguous signal for the creation of a quark-gluon plasma?

    CERN Document Server

    Bleicher, M; Bleicher, Marcus

    2005-01-01

    The excitation function of the in-plane directed flow of nucleons is studied within a non-equilibrium transport approach. It is demonstrated that a local minimum in the excitation function of the directed flow develops, which is not related to a transition into a quark-gluon plasma (QGP) phase. It is a consequence of the dynamical softening of the underlying equation of state, due to the onset of resonance matter and particle production. Thus, the interpretation of this minimum as a 'smoking gun' signature for the creation of a QGP is premature.

  20. Hydrogen desorption from hydrogen fluoride and remote hydrogen plasma cleaned silicon carbide (0001) surfaces

    Energy Technology Data Exchange (ETDEWEB)

    King, Sean W., E-mail: sean.king@intel.com; Tanaka, Satoru; Davis, Robert F. [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Nemanich, Robert J. [Department of Physics, North Carolina State University, Raleigh, North Carolina 27695 (United States)

    2015-09-15

    Due to the extreme chemical inertness of silicon carbide (SiC), in-situ thermal desorption is commonly utilized as a means to remove surface contamination prior to initiating critical semiconductor processing steps such as epitaxy, gate dielectric formation, and contact metallization. In-situ thermal desorption and silicon sublimation has also recently become a popular method for epitaxial growth of mono and few layer graphene. Accordingly, numerous thermal desorption experiments of various processed silicon carbide surfaces have been performed, but have ignored the presence of hydrogen, which is ubiquitous throughout semiconductor processing. In this regard, the authors have performed a combined temperature programmed desorption (TPD) and x-ray photoelectron spectroscopy (XPS) investigation of the desorption of molecular hydrogen (H{sub 2}) and various other oxygen, carbon, and fluorine related species from ex-situ aqueous hydrogen fluoride (HF) and in-situ remote hydrogen plasma cleaned 6H-SiC (0001) surfaces. Using XPS, the authors observed that temperatures on the order of 700–1000 °C are needed to fully desorb C-H, C-O and Si-O species from these surfaces. However, using TPD, the authors observed H{sub 2} desorption at both lower temperatures (200–550 °C) as well as higher temperatures (>700 °C). The low temperature H{sub 2} desorption was deconvoluted into multiple desorption states that, based on similarities to H{sub 2} desorption from Si (111), were attributed to silicon mono, di, and trihydride surface species as well as hydrogen trapped by subsurface defects, steps, or dopants. The higher temperature H{sub 2} desorption was similarly attributed to H{sub 2} evolved from surface O-H groups at ∼750 °C as well as the liberation of H{sub 2} during Si-O desorption at temperatures >800 °C. These results indicate that while ex-situ aqueous HF processed 6H-SiC (0001) surfaces annealed at <700 °C remain terminated by some surface C–O and

  1. Precautions for in-injection port thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) as applied to aerosol filter samples

    Science.gov (United States)

    Ho, Steven Sai Hang; Chow, Judith C.; Watson, John G.; Ting Ng, Louisa Pan; Kwok, Yuk; Ho, K. F.; Cao, Junji

    2011-03-01

    In-injection port thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) allows for analysis for >130 non-polar organic compounds on small quartz-fiber filter samples without extraction chemicals. TD-GC/MS has been applied to samples from long-term U.S. networks since it is cost effective and less labor intensive. However, analysis of large numbers of samples results in sensitivity reductions over time. Instrument sensitivity and reproducibility were examined after 100, 200, and 500 sample analyses. Analyses of standards between batches of heavily loaded samples from China and Japan showed signal decreases of 28-78% for major organic classes. In the GC injection port, residues can accumulate on the gold-plated seal resulting in analyte adsorption as well as elevating signal background. Decreases in signal response were 28-43% for n-alkanes, 33-45% for hopanes and steranes, 28-56% for PAHs, and 38-78% for phthalates when the gold-plated seal was not replaced after 500 TD-GC/MS sample analyses. Limits of detection (LODs) also increased by 14-76% for the targeted non-polar organic compounds. Residues trapped in the capillary column head can cause peak broadening and overlap. The GC/MS system, including the injection port and gold seal, the column head (where the eluted sample is pre-concentrated), and the ion source should be cleaned after every batch of 50-100 samples.

  2. Simultaneous determination of preservatives in beverages, vinegar, aqueous sauces, and quasi-drug drinks by stir-bar sorptive extraction (SBSE) and thermal desorption GC-MS.

    Science.gov (United States)

    Ochiai, Nobuo; Sasamoto, Kikuo; Takino, Masahiko; Yamashita, Satoru; Daishima, Shigeki; Heiden, Arnd C; Hoffmann, Andreas

    2002-05-01

    A method for the simultaneous determination of seven preservatives - sorbic acid, benzoic acid, and p-hydroxybenzoic acid ethyl, isopropyl, propyl, isobutyl, and butyl esters - in beverages, vinegar, aqueous sauces, and quasi-drug drinks has been developed using the stir-bar sorptive extraction technique then thermal desorption GC-MS analysis. The extraction conditions - pH, sample volume, extraction temperature, salt addition, and extraction time - were examined. d5-Benzoic acid and p-hydroxybenzoic acid sec-butyl ester were added as surrogate internal standards to compensate for the effect of sample matrix and coexisting analytes on the sorptive extraction. The linearity of the method was good over the concentration range from 1 to 1000 microg mL(-1) for sorbic acid, 10-1000 microg mL(-1) for benzoic acid, and 0.1-100 microg mL(-1) for p-hydroxybenzoic acid ethyl, isopropyl, propyl, isobutyl, and butyl esters, and the correlation coefficients were higher than 0.9984. The limit of detection ranged from 0.015 to 3.3 microg mL(-1). The recoveries (95-105%) and precision (RSD: 0.86-6.0%) of the method were examined by analyzing a sparkling soft drink, white wine, red wine, balsamic vinegar, soy sauce, and quasi-drug drink samples fortified at the 5 to 50 microg mL(-1) level.

  3. The gas chromatographic determination of volatile fatty acids in wastewater samples: evaluation of experimental biases in direct injection method against thermal desorption method.

    Science.gov (United States)

    Ullah, Md Ahsan; Kim, Ki-Hyun; Szulejko, Jan E; Cho, Jinwoo

    2014-04-11

    The production of short-chained volatile fatty acids (VFAs) by the anaerobic bacterial digestion of sewage (wastewater) affords an excellent opportunity to alternative greener viable bio-energy fuels (i.e., microbial fuel cell). VFAs in wastewater (sewage) samples are commonly quantified through direct injection (DI) into a gas chromatograph with a flame ionization detector (GC-FID). In this study, the reliability of VFA analysis by the DI-GC method has been examined against a thermal desorption (TD-GC) method. The results indicate that the VFA concentrations determined from an aliquot from each wastewater sample by the DI-GC method were generally underestimated, e.g., reductions of 7% (acetic acid) to 93.4% (hexanoic acid) relative to the TD-GC method. The observed differences between the two methods suggest the possibly important role of the matrix effect to give rise to the negative biases in DI-GC analysis. To further explore this possibility, an ancillary experiment was performed to examine bias patterns of three DI-GC approaches. For instance, the results of the standard addition (SA) method confirm the definite role of matrix effect when analyzing wastewater samples by DI-GC. More importantly, their biases tend to increase systematically with increasing molecular weight and decreasing VFA concentrations. As such, the use of DI-GC method, if applied for the analysis of samples with a complicated matrix, needs a thorough validation to improve the reliability in data acquisition.

  4. Trace analysis of chlorophenols in river water samples by stir bar sorptive extraction with in situ derivatization and thermal desorption-gas chromatography-mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Kawaguchi, M.; Ishii, Y.; Okanouchi, N.; Sakui, N.; Ito, R.; Inoue, K.; Nakazawa, H. [Hoshi Univ., Tokyo (Japan). Dept. of Analytical Chemistry, Faculty of Pharmaceutical Sciences; Saito, K. [Saitama Institute of Public Health, Saitama (Japan). Dioxin Research Group

    2004-09-15

    Many analytical methods for the determination of chlorophenols in water samples have been reported including gas chromatography-mass spectrometry (GC-MS). However, GC-MS was initially used for the determination of phenol compounds even though derivatization was required. The derivatization leads to sharper peaks and hence to better separation and higher sensitivity for the phenols. However, the derivatization faces the risk of contamination and hence an overestimation of chlorophenols concentration. In order to overcome these problems, in situ derivatization has been developed, which involves the simple addition of a reagent to a liquid sample. Recently, a new sorptive extraction technique that uses a stir bar coated with polydimethylsiloxane (PDMS) was developed. The technique is known as stir bar sorptive extraction (SBSE). We already reported that determination of 4-tert-octylphenol (OP) and 4-nonylphenol (NP) in river water4 and body fluid samples by using SBSE. In addition, SBSE with in situ derivatization has been successfully used in the determination of bisphenol A (BPA) in human body fluid samples6 and phenolic xenoestrogens in river water samples. The aim of this study is to determine trace amounts of chlorophenols in water samples by SBSE with in situ derivatization, followed by thermal desorption (TD)-GC-MS. The developed method was applied to determination of chlorophenols in river water samples.

  5. Separation and analysis of trace volatile formaldehyde in aquatic products by a MoO₃/polypyrrole intercalative sampling adsorbent with thermal desorption gas chromatography and mass spectrometry.

    Science.gov (United States)

    Ma, Yunjian; Zhao, Cheng; Zhan, Yisen; Li, Jianbin; Zhang, Zhuomin; Li, Gongke

    2015-05-01

    An in situ embedded synthesis strategy was developed for the preparation of a MoO3 /polypyrrole intercalative sampling adsorbent for the separation and analysis of trace volatile formaldehyde in aquatic products. Structural and morphological characteristics of the MoO3 /polypyrrole intercalative adsorbent were investigated by a series of characterization methods. The MoO3 /polypyrrole sampling adsorbent possessed a higher sampling capacity and selectivity for polar formaldehyde than commonly used commercial adsorbent Tenax TA. Finally, the MoO3 /polypyrrole adsorbent was packed in the thermal desorption tube that was directly coupled to gas chromatography with mass spectrometry for the analysis of trace volatile formaldehyde in aquatic products. Trace volatile formaldehyde from real aquatic products could be selectively sampled and quantified to be 0.43-6.6 mg/kg. The detection limit was achieved as 0.004 μg/L by this method. Good recoveries for spiked aquatic products were achieved in range of 75.0-108% with relative standard deviations of 1.2-9.0%. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Determination of off-flavor compounds, 2-methylisoborneol and geosmin, in salmon fillets using stir bar sorptive extraction-thermal desorption coupled with gas chromatography-mass spectrometry.

    Science.gov (United States)

    Ruan, E D; Aalhus, J L; Summerfelt, S T; Davidson, J; Swift, B; Juárez, M

    2013-12-20

    A sensitive and solvent-less method for the determination of musty and earthy off-flavor compounds, 2-methylisoborneol (MIB) and geosmin (GSM), in salmon tissue was developed using stir bar sorptive extraction-thermal desorption coupled with gas chromatography-mass spectrometry (SBSE-TD-GCMS). MIB and GSM were solid phase extracted using polydimethylsiloxane (PDMS) coated stir bars, analyzed by gas chromatography, and detected in full scan mode of mass selective detector (MSD). Using this method, the calibration curves of MIB and GSM were linear in the range of 0.3-100ng/L, with a correlation coefficient above 0.999 and RSDs less than 4% (n=4). The limit of detection (LOD, S/N=3, n=6) and limit of quantification (LOQ, S/N=10, n=6) of MIB and GSM were both ∼0.3 and 1ng/L, respectively. The recoveries of MIB and GSM were 22% and 29% by spike in 30ng/L standard compounds, 23% and 30% by spike-in 100ng/L standard compounds in salmon tissue samples with good precision (<8% of RSDs, n=6), respectively. The recoveries of MIB and GSM were better than reported methodologies using SPME fibres (<10%) in fish tissue samples. This method was successfully applied to monitor and characterize depurated salmon fillet samples (0, 3, 6 and 10 days).

  7. Ion mobility spectrometry-mass spectrometry studies of ion processes in air at atmospheric pressure and their application to thermal desorption of 2,4,6-trinitrotoluene

    Science.gov (United States)

    Sabo, Martin; Malásková, Michaela; Matejčík, Štefan

    2014-02-01

    In this study we have investigated the negative reactant ion formation in a negative corona discharge (CD) using the corona discharge ion mobility spectrometry orthogonal acceleration time-of-flight (CD-IMS-oaTOF) technique. The reactant ions were formed in the CD operating in the reverse gas flow mode at an elevated temperature of 363.5 K in synthetic and ambient air. Under these conditions mainly O_{2}^{-} and their clusters were formed. We have also studied the influence of CCl4 admixture to air (dopant gas) on the composition of the reactant ions, which resulted in the formation of Cl- and its clusters with a reduced ion mobility of 3.05 cm2 V-1 s-1 as a major reactant ion peak. Additional IMS peaks with reduced ion mobilities of 2.49, 2.25 and 2.03 cm2 V-1 s-1 were detected, and Cl- · (NO2) and Cl- · (NO)n(n = 2, 3) anions were identified. The negative reactant ions were used to detect 2,4,6 trinitrotoluene (TNT) using the thermal desorption (TD) technique using a CD-IMS instrument. Using TD sampling and a negative CD ion source doped by CCl4 we have achieved a limit of detection of 350 pg for direct surface analysis of TNT.

  8. Detection of gaseous compounds by needle trap sampling and direct thermal-desorption photoionization mass spectrometry: concept and demonstrative application to breath gas analysis.

    Science.gov (United States)

    Kleeblatt, Juliane; Schubert, Jochen K; Zimmermann, Ralf

    2015-02-01

    A fast detection method to analyze gaseous organic compounds in complex gas mixtures was developed, using a needle trap device (NTD) in conjunction with thermal-desorption photoionization time-of-flight mass spectrometry (TD-PI-TOFMS). The mass spectrometer was coupled via a deactivated fused silica capillary to an injector of a gas chromatograph. In the hot injector, the analytes collected on the NTD were thermally desorbed and directly transferred to the PI-TOFMS ion source. The molecules are softly ionized either by single photon ionization (SPI, 118 nm) or by resonance enhanced multiphoton ionization (REMPI, 266 nm), and the molecular ion signals are detected in the TOF mass analyzer. Analyte desorption and the subsequent PI-TOFMS detection step only lasts ten seconds. The specific selectivity of REMPI (i.e., aromatic compounds) and universal ionization characteristics render PI-MS as a promising detection system. As a first demonstrative application, the alveolar phase breath gas of healthy, nonsmoking subjects was sampled on NTDs. While smaller organic compounds such as acetone, acetaldehyde, isoprene, or cysteamine can be detected in the breath gas with SPI, REMPI depicts the aromatic substances phenol and indole at 266 nm. In the breath gas of a healthy, smoking male subject, several xenobiotic substances such as benzene, toluene, styrene, and ethylbenzene can be found as well. Furthermore, the NTD-REMPI-TOFMS setup was tested for breath gas taken from a mechanically ventilated pig under continuous intravenous propofol (2,6-diisopropylphenol, narcotic drug) infusion.

  9. Volatile organic compounds in air at urban and industrial areas in the Tarragona region by thermal desorption and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Ras, Maria Rosa; Marcé, Rosa Maria; Borrull, Francesc

    2010-02-01

    Annual trends of a group of 66 volatile organic compounds (VOCs), containing 20 ozone precursors, were the aim of a sampling campaign carried out for a year in air at urban and industrial areas from Tarragona region. VOCs were determined by active collection on multisorbent tubes, followed by thermal desorption and gas chromatography-mass spectrometry. The analytical method was developed and validated, showing good levels of detection and quantification, recoveries, precision, and linearity for all the compounds in the range being studied. All the industrial and urban samples taken during the sampling campaign were similar in their qualitative composition. The most abundant compound in all urban and industrial sites was i-pentane, with concentrations between 15.2 and 202.1 microg m(-3) in urban sites and between 1.3 and 98.6 microg m(-3) in industrial sites. In urban sites, the following compounds in order of abundance were toluene, n-pentane, m,p-xylene, and o-xylene, with maximum levels of 150.6, 45.8, 42.3, and 31.7 microg m(-3), respectively. In industrial sites, the most abundant compounds depended on the sampled site.

  10. Determination of parabens in house dust by pressurised hot water extraction followed by stir bar sorptive extraction and thermal desorption-gas chromatography-mass spectrometry.

    Science.gov (United States)

    Ramírez, Noelia; Marcé, Rosa Maria; Borrull, Francesc

    2011-09-16

    This study describes the development of a new method for determining p-hydroxybenzoic esters (parabens) in house dust. This optimised method was based on the pressurised hot water extraction (PHWE) of house dust, followed by the acetylation of the extracted parabens, stir bar sorptive extraction (SBSE) with a polydimethylsiloxane stir bar, and finally analysis using thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). The combination of SBSE and PHWE allows the analytes to be preconcentrated and extracted from the aqueous extract in a single step with minimal manipulation of the sample. Furthermore the in situ acetylation of parabens prior to SBSE improved their extraction efficiency and their GC-MS signal. The method showed recoveries of between 40 and 80%, good linearity, repeatability and reproducibility (paraben to 2.1 ng g(-1) for methyl paraben) and quantification (from 3.3 ng g(-1) for propyl paraben to 8.5 ng g(-1) for methyl paraben). The proposed method was applied to the analysis of house dust samples. All the target parabens were found in the samples. Methyl and propyl parabens were the most abundant, with concentrations up to 2440 ng g(-1) and 910 ng g(-1), respectively. The high levels of parabens found in the samples confirm the importance of determining organic contaminants in indoor environments.

  11. Carbamazepine in municipal wastewater and wastewater sludge: ultrafast quantification by laser diode thermal desorption-atmospheric pressure chemical ionization coupled with tandem mass spectrometry.

    Science.gov (United States)

    Mohapatra, D P; Brar, S K; Tyagi, R D; Picard, P; Surampalli, R Y

    2012-09-15

    In this study, the distribution of the anti-epileptic drug carbamazepine (CBZ) in wastewater (WW) and aqueous and solid phases of wastewater sludge (WWS) was carried out. A rapid and reliable method enabling high-throughput sample analysis for quicker data generation, detection, and monitoring of CBZ in WW and WWS was developed and validated. The ultrafast method (15s per sample) is based on the laser diode thermal desorption-atmospheric pressure chemical ionization (LDTD-APCI) coupled to tandem mass spectrometry (MS/MS). The optimization of instrumental parameters and method application for environmental analysis are presented. The performance of the novel method was evaluated by estimation of extraction recovery, linearity, precision and detection limit. The method detection limits was 12 ng L(-1) in WW and 3.4 ng g(-1) in WWS. The intra- and inter-day precisions were 8% and 11% in WW and 6% and 9% in WWS, respectively. Furthermore, three extraction methods, ultrasonic extraction (USE), microwave-assisted extraction (MAE) and accelerated solvent extraction (ASE) with three different solvent condition such as methanol, acetone and acetonitrile:ethyle acetate (5:1, v/v) were compared on the basis of procedural blank and method recovery. Overall, ASE showed the best extraction efficiency with methanol as compared to USE and MAE. Furthermore, the quantification of CBZ in WW and WWS samples showed the presence of contaminant in all stages of the treatment plant.

  12. Novel characterization of the adsorption sites in large pore metal-organic frameworks: combination of X-ray powder diffraction and thermal desorption spectroscopy.

    Science.gov (United States)

    Soleimani-Dorcheh, Ali; Dinnebier, Robert E; Kuc, Agnieszka; Magdysyuk, Oxana; Adams, Frank; Denysenko, Dmytro; Heine, Thomas; Volkmer, Dirk; Donner, Wolfgang; Hirscher, Michael

    2012-10-05

    The preferred adsorption sites of xenon in the recently synthesized metal-organic framework MFU-4l(arge) possessing a bimodal pore structure (with pore sizes of 12 Å and 18.6 Å) were studied via the combination of low temperature thermal desorption spectroscopy and in situ X-ray powder diffraction. The diffraction patterns were collected at 110 K and 150 K according to the temperature of the desorption maxima. The maximum entropy method was used to reconstruct the electron density distribution of the structure and to localize the adsorbed xenon using refined data of the Xe-filled and empty sample. First principles calculations revealed that Xe atoms exclusively occupy the Wyckoff 32f position at approximately 2/3 2/3 2/3 along the body diagonal of the cubic crystal structure. At 110 K, Xe atoms occupy all 32 f positions (8 atoms per pore) while at 150 K the occupancy descends to 25% (2 atoms per pore). No Xe occupation of the small pores is observed by neither experimental measurements nor theoretical studies.

  13. Thermal desorption studies of isotopically-labeled oxygen-induced superconductivity in La sub 2 CuO sub 4+. delta

    Energy Technology Data Exchange (ETDEWEB)

    Shinn, N.D.; Bartram, M.E.; Schirber, J.E.; Overmyer, D.L.; Rogers, J.W. Jr. (Sandia National Labs., Albuquerque, NM (USA)); Fisk, Z.; Cheong, S.W. (Los Alamos National Lab., NM (USA))

    1990-01-01

    Isotopically-labeled oxygen enrichment and thermal desorption mass spectroscopy (TDMS) have been combined to study interstitial oxygen desorption from superconducting La{sub 2}CuO{sub 4+{delta}} ({delta} {le} 0.032). Single crystal samples of magnetic insulating La{sub 2}CuO{sub 4.00} were annealed at 860K under 1--3 kbar oxygen pressure for 12--100 hours to yield hole-doped, superconducting La{sub 2}CuO{sub 4+{delta}} samples with 35K < {Tc} < 40K. Whereas no TDMS signals were observed for the insulator, rapid bursts (FWHM < 0.5 sec) of molecular oxygen were observed above 350K while heating the superconductor at less than 1 K sec{sup {minus}1} in high vacuum. A kinetic model is proposed in which the interstitial oxygen diffuses to internal grain boundaries and defects during heating, thereby inducing stress in the lattice as it attempts to revert to the LaCuO{sub 4.00} crystal structure. This stress is relieved by lattice fracture at grain boundaries during the TDMS experiment, releasing the trapped oxygen from the sample as micro-cracks are formed. In addition, the facile oxygen exchange between interstitial and lattice oxygen sites has been discovered by TDMS and weight gain measurements from isotopically-enriched crystals, supporting the structural model of Chaillout, et al. in which the interstitial oxygen atom dimerizes with a lattice oxygen ion.

  14. Direct quantitative analysis of phthalate esters as micro-contaminants in cleanroom air and wafer surfaces by auto-thermal desorption--gas chromatography--mass spectrometry.

    Science.gov (United States)

    Kang, Yuhao; Den, Walter; Bai, Hsunling; Ko, Fu-Hsiang

    2005-04-01

    This study established an analytical method for the trace analyses of two phthalate esters, including diethyl phthalate (DEP) and di-n-butyl phthalate (DBP), known as the major constituents of cleanroom micro-contamination detrimental to the reliability of semiconductor devices. Using thermal desorption coupled with a GC-MS system, standard tubes were prepared by delivering liquid standards pre-vaporized by a quasi-vaporizer into Tenax GR tubes for calibration. This method was capable of achieving detection limits of 0.05 microg m(-3) for 0.1 m3 air samples and 0.03 ng cm(-2) for 150-mm wafer surface density. Actual samples collected from a semiconductor cleanroom showed that the concentration of DBP in a polypropylene wafer box (0.45 microg m(-3)) was nearly four times higher than that in the cleanroom environment (0.12 microg m(-3)). The surface contamination of DBP was 0.67 ng cm(-2) for a wafer stored in the wafer box for 24 h. Furthermore, among the three types of heat-resistant O-ring materials tested, Kalrez was found to be particularly suitable for high-temperature processes in semiconductor cleanrooms due to their low emissions of organic vapors. This analytical procedure should serve as an effective monitoring method for the organic micro-contamination in cleanroom environments.

  15. Thermal desorption/tunable vacuum-ultraviolet time-of-flight photoionization aerosol mass spectrometry for investigating secondary organic aerosols in chamber experiments.

    Science.gov (United States)

    Fang, Wenzheng; Gong, Lei; Shan, Xiaobin; Liu, Fuyi; Wang, Zhenya; Sheng, Liusi

    2011-12-01

    This paper describes thermal desorption/tunable vacuum-ultraviolet photoionization time-of-flight aerosol mass spectrometry (TD-VUV-TOF-PIAMS) for the real-time analysis of secondary organic aerosols (SOAs) in smog chamber experiments. SOAs are sampled directly from atmospheric pressure and are focused through an aerodynamic lens assembly into the mass spectrometer. Once the particles have entered the source region, they impact on a heater and are vaporized. The nascent vapor is then softly ionized by tunable VUV synchrotron radiation. TD-VUV-TOF-PIAMS was used in conjunction with the smog chamber to study SOA formation from the photooxidation of toluene with hydroxyl radicals. The ionization energies (IEs) of these SOA products are sometimes very different with each other. As the ideal photon source is tunable, its energy can be adjusted for each molecular to be ionized. The mass spectra obtained at different photon energies are then to be useful for molecular identification. Real-time analysis of the mass spectra of SOAs is compared with previous off-line measurements. These results illustrate the potential of TD-VUV-TOF-PIAMS for direct molecular characterization of SOAs in smog chamber experiments.

  16. Multi-residue off-flavour profiling in wine using stir bar sorptive extraction-thermal desorption-gas chromatography-mass spectrometry.

    Science.gov (United States)

    Franc, Céline; David, Frank; de Revel, Gilles

    2009-04-10

    A multi-residue method (MRM) for the detection and quantification of eight compounds responsible for off-flavours in wine using stir bar sorptive extraction (SBSE) followed by thermal desorption (TD) and gas chromatography-mass spectrometry (GC-MS) analysis is presented. The extraction and desorption conditions were optimised in order to get the best compromise for the simultaneous analysis of the eight target solutes, belonging to different chemical classes. The analytical conditions enable the quantification of the solutes below their respective organoleptic perception thresholds in wine. The method displayed good linearity over the concentration ranges explored in wine as well as excellent repeatability (RSD below 6%) and good reproducibility (RSD below 24%). The developed methodology was applied to the analysis of several wines and showed good agreement with the results collected with headspace solid-phase microextraction (HS-SPME) or liquid-liquid extraction (LLE) followed by GC-MS or electron capture detection (ECD). Good correlation was also found between the analytical and sensory results.

  17. Optimization of a Dynamic Headspace-Thermal Desorption-Gas Chromatography/Mass Spectrometry procedure for the determination of furfurals in vinegars.

    Science.gov (United States)

    Manzini, Simona; Durante, Caterina; Baschieri, Carlo; Cocchi, Marina; Sighinolfi, Simona; Totaro, Sara; Marchetti, Andrea

    2011-08-15

    The use of a Dynamic Headspace System (DHS) device combined with a Thermal Desorption Unit (TDU) interfaced to a Gas Chromatography/Mass Spectrometry (GC/MS) system is proposed for the determination of furfurals in oenological products. An experimental design protocol has been employed for the optimization of the instrumental settings concerning DHS and TDU extraction and desorption steps. It has been possible to individuate the following optimized conditions: incubation temperature 40°C, purge volume 800 mL, dry volume 1500 mL, TDU hold time 5 min and incubation time 10 min. The performance of two different SPE sorbents, namely Tenax TA and Tenax GR used for the furfurals trapping, was investigated too. The developed DHS sampling procedure showed good reproducibility values with a RSD% lower than 10% for all the monitored species. The optimized experimental settings have been used to determine furfurals in several vinegar samples obtained by traditional procedure starting from cooked grape musts, i.e. in Aceto Balsamico Tradizionale di Modena (ABTM). In fact, the control of these species is extremely important for quality and safety issues.

  18. Threshold character of temperatures on deuterium thermal desorption in Mg-V composite grown atom-by-atom

    Science.gov (United States)

    Neklyudov, I. M.; Morozov, O. M.; Kulish, V. G.; Zhurba, V. I.; Galitskiy, A. G.; Lomino, N. S.; Kuprin, A. S.; Ovcharenko, V. D.; Reshetnyak, E. N.

    2012-08-01

    The plasma evaporation-sputtering method was applied to make composite materials of the Mg-V system. The ion-implanted deuterium desorption temperature variations as a function of the component concentration were studied. It has been established that, by introducing vanadium into magnesium, the deuterium desorption temperature can be appreciably decreased (to 300-330 K) in comparison with the case of deuterium desorption from magnesium (~800 K). A step-like form of the curve of deuterium desorption temperature evidences on the presence of two different structure states of the Mg-V system depending on the ratio of components. The deuterium temperature decrease can be caused by filamentary inclusions formed, in the process of composite making and annealing, by the insoluble component (vanadium) atoms providing the deuterium diffusion from the sample at a lower temperature (channels for deuterium diffusion through the surface barrier). A necessary high diffusion mobility of deuterium is provided by the amorphous state of Mg83+xVx samples. The deuterium desorption data obtained on the example of Mg-V and Mg-Zr composites provide support for further research into hydrogen storage materials containing low-soluble chemical elements in the alloy components.

  19. Path Creation

    DEFF Research Database (Denmark)

    Karnøe, Peter; Garud, Raghu

    2012-01-01

    This paper employs path creation as a lens to follow the emergence of the Danish wind turbine cluster. Supplier competencies, regulations, user preferences and a market for wind power did not pre-exist; all had to emerge in a tranformative manner involving multiple actors and artefacts. Competenc......This paper employs path creation as a lens to follow the emergence of the Danish wind turbine cluster. Supplier competencies, regulations, user preferences and a market for wind power did not pre-exist; all had to emerge in a tranformative manner involving multiple actors and artefacts....... Competencies emerged through processes and mechanisms such as co-creation that implicated multiple learning processes. The process was not an orderly linear one as emergent contingencies influenced the learning processes. An implication is that public policy to catalyse clusters cannot be based...

  20. Analysis of trimethoprim, lincomycin, sulfadoxin and tylosin in swine manure using laser diode thermal desorption-atmospheric pressure chemical ionization-tandem mass spectrometry.

    Science.gov (United States)

    Solliec, Morgan; Massé, Daniel; Sauvé, Sébastien

    2014-10-01

    A new extraction method coupled to a high throughput sample analysis technique was developed for the determination of four veterinary antibiotics. The analytes belong to different groups of antibiotics such as chemotherapeutics, sulfonamides, lincosamides and macrolides. Trimethoprim (TMP), sulfadoxin (SFX), lincomycin (LCM) and tylosin (TYL) were extracted from lyophilized manure using a sonication extraction. McIlvaine buffer and methanol (MeOH) were used as extraction buffers, followed by cation-exchange solid phase extraction (SPE) for clean-up. Analysis was performed by laser diode thermal desorption-atmospheric pressure chemical-ionization (LDTD-APCI) tandem mass spectrometry (MS/MS) with selected reaction monitoring (SRM) detection. The LDTD is a high throughput sample introduction method that reduces total analysis time to less than 15s per sample, compared to minutes when using traditional liquid chromatography (LC). Various SPE parameters were optimized after sample extraction: the stationary phase, the extraction solvent composition, the quantity of sample extracted and sample pH. LDTD parameters were also optimized: solvent deposition, carrier gas, laser power and corona discharge. The method limit of detection (MLD) ranged from 2.5 to 8.3 µg kg(-1) while the method limit of quantification (MLQ) ranged from 8.3 to 28µgkg(-1). Calibration curves in the manure matrix showed good linearity (R(2)≥ 0.996) for all analytes and the interday and intraday coefficients of variation were below 14%. Recoveries of analytes from manure ranged from 53% to 69%. The method was successfully applied to real manure samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Analysis of trace contamination of phthalate esters in ultrapure water using a modified solid-phase extraction procedure and automated thermal desorption-gas chromatography/mass spectrometry.

    Science.gov (United States)

    Liu, Hsu-Chuan; Den, Walter; Chan, Shu-Fei; Kin, Kuan Tzu

    2008-04-25

    The present study was aimed to develop a procedure modified from the conventional solid-phase extraction (SPE) method for the analysis of trace concentration of phthalate esters in industrial ultrapure water (UPW). The proposed procedure allows UPW sample to be drawn through a sampling tube containing hydrophobic sorbent (Tenax TA) to concentrate the aqueous phthalate esters. The solid trap was then demoisturized by two-stage gas drying before subjecting to thermal desorption and analysis by gas chromatography-mass spectrometry. This process removes the solvent extraction procedure necessary for the conventional SPE method, and permits automation of the analytical procedure for high-volume analyses. Several important parameters, including desorption temperature and duration, packing quantity and demoisturizing procedure, were optimized in this study based on the analytical sensitivity for a standard mixture containing five different phthalate esters. The method detection limits for the five phthalate esters were between 36 ng l(-1) and 95 ng l(-1) and recovery rates between 15% and 101%. Dioctyl phthalate (DOP) was not recovered adequately because the compound was both poorly adsorbed and desorbed on and off Tenax TA sorbents. Furthermore, analyses of material leaching from poly(vinyl chloride) (PVC) tubes as well as the actual water samples showed that di-n-butyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP) were the common contaminants detected from PVC contaminated UPW and the actual UPW, as well as in tap water. The reduction of DEHP in the production processes of actual UPW was clearly observed, however a DEHP concentration of 0.20 microg l(-1) at the point of use was still being quantified, suggesting that the contamination of phthalate esters could present a barrier to the future cleanliness requirement of UPW. The work demonstrated that the proposed modified SPE procedure provided an effective method for rapid analysis and contamination

  2. Determination of five booster biocides in seawater by stir bar sorptive extraction-thermal desorption-gas chromatography-mass spectrometry.

    Science.gov (United States)

    Giráldez, I; Chaguaceda, E; Bujalance, M; Morales, E

    2013-01-04

    Stir bar sorptive extraction (SBSE) and thermal desorption (TD)-gas chromatography-mass spectrometry (GC-MS) have been optimized for the determination of five organic booster biocides (Chlorothalonil, Dichlofluanid, Sea-Nine 211, Irgarol 1051 and TCMTB) in seawater samples. The parameters affecting the desorption and absorption steps were investigated using 10 mL seawater samples. The optimised conditions consisted of an addition of 0.2 g mL(-1) KCl to the sample, which was extracted with 10mm length, 0.5mm film thickness stir bars coated with polydimethylsiloxane (PDMS), and stirred at 900 rpm for 90 min at room temperature (25 °C) in a vial. Desorption was carried out at 280 °C for 5 min under 50 mL min(-1) of helium flow in the splitless mode while maintaining a cryotrapping temperature of 20 °C in the programmed-temperature vaporization (PTV) injector of the GC-MS system. Finally, the PTV injector was ramped to a temperature of 280 °C and the analytes were separated in the GC and detected by MS using the selected-ion monitoring (SIM) mode. The detection limits of booster biocides were found to be in the range of 0.005-0.9 μg L(-1). The regression coefficients were higher than 0.999 for all analytes. The average recovery was higher than 72% (R.S.D.: 7-15%). All these figures of merit were established running samples in triplicate. This simple, accurate, sensitive and selective analytical method may be used for the determination of trace amounts of booster biocides in water samples from marinas.

  3. Determination of Glycol Ethers in Ambient Air by Adsorption Sampling and Thermal Desorption with GC/MS Analysis: Performance Evaluation and Field Application

    Directory of Open Access Journals (Sweden)

    Young-Kyo Seo

    2012-01-01

    Full Text Available Some of glycol ethers, such as 2-methoxyethanol (2-ME and 2-ethoxyethanol (2-EE are known to be toxic and classified as hazardous air pollutants in USA, Japan and Germany. In Korea, however, there has been no study conducted so far for these compounds in ambient air. In addition, no clear methodologies for the measurement of glycol ethers have been yet established. We carried out this study to evaluate a sampling and analytical method for the determination of glycol ethers, in ambient air samples collected in specific industrial areas of South Korea. To measure glycol ethers, adsorption sampling and thermal desorption with GC/MS analysis were used in this study. The analytical method showed good repeatability, linearity and sensitivity. The lower detection limits were estimated to be approximately 0.3∼0.5 ppb. Based on storage tests, it was suggested that samples should be analyzed within two weeks. It was also demonstrated that this method can be used for the simultaneous measurement of glycol ethers and other aromatic VOCs such as benzene, toluene, and xylenes. Field sampling campaign was carried out at 2 sites, located in a large industrial area, from October 2006 to June 2007, and a total of 480 samples were collected seasonally. Among them, 2-ME was not detected from any samples, while 2-EE and 2-Ethyloxyethylacetate (2-EEA were found in 7 and 70 samples, respectively. The measured concentrations of 2-EE and 2-EEA for samples were ranged from 0.7-2.5 ppb and from 0.5-10.5 ppb, respectively. To our knowledge, this is the first measurement report for glycol ethers in the ambient atmosphere not only in Korea but also the rest of the world.

  4. Au and Al Schottky barrier formation on GaAs (100) surfaces prepared by thermal desorption of a protective arsenic coating

    Energy Technology Data Exchange (ETDEWEB)

    Spindt, C.J.; Yamada, M.; Meissner, P.L.; Miyano, K.E.; Herrera, A.; Spicer, W.E. (Stanford Electronics Laboratories, Stanford University, Stanford, California 94305-4055 (US)); Arko, A.J. (Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (US))

    1991-07-01

    Soft x-ray photoemission spectroscopy has been used to investigate the initial stages of Schottky barrier formation on GaAs (100) surfaces prepared by the thermal desorption of an As cap. This work was motivated by a previous study (Brillson {ital et} {ital al}., J. Vac. Sci. Technol. B {bold 6}, 1263 (1988)) of identically grown and capped samples which reported unpinned'' Schottky barrier formation, with barrier heights falling over a wide range (0.75 eV) of energies. This large energy range is a striking result, as a considerable number of prior studies on both (110) and (100) surfaces have found that all metals will pin in a narrow (0.25 eV) range near midgap. Since Au and Al are the extremes of the larger 0.75 eV span of Schottky barriers, we have studied the deposition of these two metals. We found that the barrier height measurements on the low doped {ital n}-type samples used in this work and in the paper referenced above are affected by photovoltaic effects, even at room temperature. These photovoltaic effects cause shifts in the band bending, which are an artifact of the measurement. We also performed measurements on more heavily doped samples, and the photovoltaic effects were removed. In addition, we point out that Au--Ga alloying makes the case of Au potentially misleading. With the photovoltaic effects removed, and the Au--Ga alloying carefully accounted for, we found that the barriers heights for Au and Al differ by only 0.25 eV.

  5. Determination of dithiocarbamate pesticides in occupational hygiene sampling devices using the isooctane method and comparison with an automatic thermal desorption (ATD) method.

    Science.gov (United States)

    Coldwell, Matthew R; Pengelly, Ian; Rimmer, Duncan A

    2003-01-10

    Two new methods for the determination of dithiocarbamate pesticides in occupational hygiene sampling devices are described. Dithiocarbamate spiked occupational hygiene sampling devices, consisting of glass fibre (GF/A) filters, cotton pads, cotton gloves and disposable overalls, were reduced under acidic conditions and the CS2 evolved as a decomposition product was extracted into isooctane. The isooctane was then analysed using gas chromatography with mass spectrometry, for CS2, which provided a quantitative result for dithiocarbamates. Recoveries obtained were generally within a 70-110% range and reproducibilities better than 15% RSD were typically achieved. The method has been successfully applied to samples collected during occupational exposure surveys. A second method employing automatic thermal desorption-gas chromatography-mass spectrometry (ATD-GC-MS) has also been developed and applied to the direct analysis of GF/A (airborne) samples. The method relies on the thermal degradation of dithiocarbamates to release CS2, which is used to quantify the analytes. Thiram spiked GF/A filters gave an average recovery of 107% with an RSD of 4%. The performance of the two analytical methods were directly compared by analysing sub-portions of GF/A filters collected during a survey to evaluate occupational exposures to thiram during seed treatment operations. Both methods performed well for the analysis of airborne (GF/A) samples and produced results in good agreement. ATD-GC-MS is the preferred method for studies involving GF/A (airborne) samples only. Because of the wider applicability of the isooctane method for other sampling devices, it is the preferred choice when carrying out surveys which require a dermal as well as respirable exposure assessment.

  6. Entropic Creation

    DEFF Research Database (Denmark)

    Kragh, Helge

    Entropic Creation is the first English-language book to consider the cultural and religious responses to the second law of thermodynamics, from around 1860 to 1920. According to the second law of thermodynamics, as formulated by the German physicist Rudolf Clausius, the entropy of any closed system...... the physicist William Thomson and the communist thinker Friedrich Engels. One reason for the passion of the debate was that some authors used the law of entropy increase to argue for a divine creation of the world. Consequently, the second law of thermodynamics became highly controversial. In Germany...... will inevitably increase in time, meaning that the system will decay and eventually end in a dead state of equilibrium. Application of the law to the entire universe, first proposed in the 1850s, led to the prediction of a future 'heat death', where all life has ceased and all organization dissolved. In the late...

  7. Space-time Evolution Of Quantum Fluctuations And Creation Of Quark- Gluon Plasma In Ultrarelativistic Nuclear Collisions

    CERN Document Server

    Surdutovich, Y

    1998-01-01

    We study the dynamics of quantum fluctuations which take place during the earliest stage of high-energy collision processes and the conditions under which the data from e– p deep- inelastic scattering(DIS) may serve as a guide for computing the initial data for heavy- ion collisions at high energies. Our method is essentially based on the space-time picture of these seemingly different phenomena. We analyze the inclusive quantum-mechanical measurements, in both cases, and derive the main results relying on causality. The main result is that the transition from the initial- state composite nuclei to the final-state dense system of quark-gluon fields, i.e. quark-gluon plasma, is possible only as a single quantum transition. We prove that the ultra-violet renormalization of virtual loops does not bring any scale into the problem. The scale appears only in connection with real processes of emission of quark and gluon fields and reveals itself through the collinear cut-off in the evolution equations. Thi...

  8. MOF-5 metal-organic framework as sorbent for in-field sampling and preconcentration in combination with thermal desorption GC/MS for determination of atmospheric formaldehyde.

    Science.gov (United States)

    Gu, Zhi-Yuan; Wang, Gen; Yan, Xiu-Ping

    2010-02-15

    Metal-organic frameworks (MOFs) are one kind of highly porous crystalline materials, which are constructed by metal-containing inorganic nodes and organic linkers. With large surface area and high thermal stability, MOFs have great potential as sorbents for the preconcentration of trace analytes. However, such application of MOFs to the analysis of real samples has not been reported before. Here we report the utilization of MOF-5 as sorbent for in-field sampling and preconcentration of atmospheric formaldehyde before thermal desorption (TD) GC/MS (TD-GC/MS) determination without the need for any chemical derivatization. MOF-5 gave a 53 and 73 times better concentration effect than Tenax TA (organic polymers) and Carbograph 1TD (graphitized carbon black), respectively, for TD-GC/MS determination of formaldehyde. MOF-5 showed good performance for in-field sampling and preconcentration of formaldehyde from air samples with a relative humidity less than 45%. The collected formaldehyde on MOF-5 sorbent was stable for at least 72 h at room temperature before TD-GC/MS analysis. One tube packed with 300 mg of MOF-5 lasted 200 cycles of adsorption/TD without significant loss of collection efficiency. The breakthrough volume of such a tube was 1.2 L of 28.35 mg m(-3) formaldehyde at a sampling flow rate of 100 mL min(-1). The use of MOF-5 for in-field sampling and preconcentration in combination with TD-GC/MS for the determination of formaldehyde offered a linear range covering 3 orders of magnitude, and a detection limit of 0.6 microg m(-3). The precision for six replicate cycles of in-field sampling and preconcentration for TD-GC/MS determination using one 300 mg MOF-5 packed tube ranged from 2.8% to 5.3%. The tube-to-tube reproducibility of three MOF-5 tubes prepared in parallel was 7.7%. The developed method was applied to analysis of local indoor and outdoor air samples for formaldehyde and validated by the standard method TO-11A of the United States Environmental

  9. Influence of Vegetation on the In Situ Bacterial Community and Polycyclic Aromatic Hydrocarbon (PAH) Degraders in Aged PAH-Contaminated or Thermal-Desorption-Treated Soil▿ †

    Science.gov (United States)

    Cébron, Aurélie; Beguiristain, Thierry; Faure, Pierre; Norini, Marie-Paule; Masfaraud, Jean-François; Leyval, Corinne

    2009-01-01

    The polycyclic aromatic hydrocarbon (PAH) contamination, bacterial community, and PAH-degrading bacteria were monitored in aged PAH-contaminated soil (Neuves-Maisons [NM] soil; with a mean of 1,915 mg of 16 PAHs·kg−1 of soil dry weight) and in the same soil previously treated by thermal desorption (TD soil; with a mean of 106 mg of 16 PAHs·kg−1 of soil dry weight). This study was conducted in situ for 2 years using experimental plots of the two soils. NM soil was colonized by spontaneous vegetation (NM-SV), planted with Medicago sativa (NM-Ms), or left as bare soil (NM-BS), and the TD soil was planted with Medicago sativa (TD-Ms). The bacterial community density, structure, and diversity were estimated by real-time PCR quantification of the 16S rRNA gene copy number, temporal thermal gradient gel electrophoresis fingerprinting, and band sequencing, respectively. The density of the bacterial community increased the first year during stabilization of the system and stayed constant in the NM soil, while it continued to increase in the TD soil during the second year. The bacterial community structure diverged among all the plot types after 2 years on site. In the NM-BS plots, the bacterial community was represented mainly by Betaproteobacteria and Gammaproteobacteria. The presence of vegetation (NM-SV and NM-Ms) in the NM soil favored the development of a wider range of bacterial phyla (Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Verrucomicrobia, Actinobacteria, Firmicutes, and Chloroflexi) that, for the most part, were not closely related to known bacterial representatives. Moreover, under the influence of the same plant, the bacterial community that developed in the TD-Ms was represented by different bacterial species (Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, and Actinobacteria) than that in the NM-Ms. During the 2 years of monitoring, the PAH concentration did not evolve significantly. The abundance of gram-negative (GN

  10. Electronic structure and Schottky-barrier formation on GaAs (100) surfaces prepared by thermal desorption of a protective arsenic coating

    Energy Technology Data Exchange (ETDEWEB)

    Spindt, C.J.; Yamada, M.; Meissner, P.L.; Miyano, K.E.; Kendelewicz, T.; Herrera-Gomez, A.; Spicer, W.E. (Stanford Electronics Laboratories, Stanford University, Stanford, California 94305-4055 (United States)); Arko, A.J. (Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States))

    1992-05-15

    Soft-x-ray photoemission spectroscopy has been used to characterize GaAs(100) surfaces and interfaces grown by molecular-beam epitaxy and prepared by the thermal desorption of a protective As coating. The samples studied were grown and arsenic capped identically to those used in a previous study (Brillson {ital et} {ital al}., J. Vac. Sci. Technol. B 6, 1263 (1988)). In this previous work, unpinned'' Schottky-barrier formation was reported, with barrier heights over a wide (0.75-eV) range. This is a striking result, as it was previously believed that all metals will pin GaAs surfaces in a narrow energy range near the middle of the band gap. This large range of barrier heights later led to the suggestion that the (100) surface could become an insulating layer that could screen out the effects of metal-induced gap states. Motivated by this work, we have studied Al and Au Schottky barriers since the deposition of these two metals gave the extreme low and high barriers in the 0.75-eV range. We have also characterized the clean surfaces prepared by desorbing the As caps at different temperatures. The As 3{ital d} and Ga 3{ital d} core levels showed that the surface stoichiometry could be varied significantly with the desorption temperature. The As 3{ital d} line shape was found to be the best indication of the surface stoichiometry after the anneal. The valence-band spectra did not show any strong features which could be used to determine when the sample was completely decapped. The electronic structure of the surface layer was investigated experimentally, and no evidence of an insulating reconstruction was found. In our study of band bending, we found that the low-doped samples used here and in the earlier study showed significant photovoltages resulting in incorrect band-bending measurements. We also found that the Au measurements are made difficult by the presence of core-level shifts due to Au-Ga alloying.

  11. Green Ocean Amazon (GoAmazon) 2014/15. Semi-Volatile Thermal Desorption Aerosol Gas Chromatograph (SVTAG) Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, A. H. [Univ. of California, Berkeley, CA (United States); Yee, L. D. [Univ. of California, Berkeley, CA (United States); Issacman-VanWertz, G. [Univ. of California, Berkeley, CA (United States); Wernis, R. A. [Univ. of California, Berkeley, CA (United States)

    2016-03-01

    In areas where biogenic emissions are oxidized in the presence of anthropogenic pollutants such as SO2, NOx, and black carbon, it has become increasingly apparent that secondary organic aerosol (SOA) formation from biogenic volatile organic compounds (VOCs) is substantially enhanced. Research is urgently needed to elucidate fundamental processes of natural and anthropogenically influenced VOC oxidation and the contribution of these processes to SOA formation. GoAmazon 2014/15 afforded study of the chemical transformations in the region downwind of Manaus, Brazil, where local biogenic VOC emissions are high, and their chemical oxidation can be studied both inside and outside of the urban plume to differentiate the role of anthropogenic influence on secondary aerosol formation during oxidation of these natural VOC emissions. To understand the connection between primary biogenic VOC emissions and their secondary products that form aerosols, we made time-resolved molecular level measurements by deploying a Semi-Volatile Thermal Desorption Aerosol Gas Chromatograph (SV-TAG) and a sequential filter sampler during two intensive operational periods (IOPs) of the GoAmazon 2014/15 field campaign. The SV-TAG measured semi-volatile organic compounds in both the gas and particle phases and the sequential filter sampler collected aerosols on quartz fiber filters in four-hour increments used for offline analysis. SV-TAG employed novel online derivatization that provided chemical speciation of highly oxygenated or functionalized compounds that comprise a substantial fraction of secondary organic aerosols, yet are poorly characterized. It also provided partitioning of these compounds between the vapor and particle phases at sufficient time resolution to define the importance of competing atmospheric processes. These measurements were supported by offline analysis of the filters using two-dimensional gas chromatography (GC x GC) with high-resolution time-of-flight mass spectrometry

  12. Determination of a wide range of volatile organic compounds in ambient air using multisorbent adsorption/thermal desorption and gas chromatography/mass spectrometry

    Science.gov (United States)

    Pankow, J.F.; Luo, W.; Isabelle, L.M.; Bender, D.A.; Baker, R.J.

    1998-01-01

    Adsorption/thermal desorption with multisorbent air-sampling cartridges was developed for the determination of 87 method analytes including halogenated alkanes, halogenated alkenes, ethers, alcohols, nitriles, esters, ketones, aromatics, a disulfide, and a furan. The volatilities of the compounds ranged from that of dichlorofluoromethane (CFC12) to that of 1,2,3- trichlorobenzene. The eight most volatile compounds were determined using a 1.5-L air sample and a sample cartridge containing 50 mg of Carbotrap B and 280 mg of Carboxen 1000; the remaining 79 compounds were determined using a 5-L air sample and a cartridge containing 180 mg of Carbotrap B and 70 mg of Carboxen 1000. Analysis and detection were by gas chromatography/mass spectrometry. The minimum detectable level (MDL) concentration values ranged from 0.01 parts per billion by volume (ppbv) for chlorobenzene to 0.4 ppbv for bromomethane; most of the MDL values were in the range 0.02-0.06 ppbv. No breakthrough was detected with the prescribed sample volumes. Analyte stability on the cartridges was very good. Excellent recoveries were obtained with independent check standards. Travel spike recoveries ranged from 90 to 110% for 72 of the 87 compounds. The recoveries were less than 70% for bromomethane and chloroethene and for a few compounds such as methyl acetate that are subject to losses by hydrolysis; the lowest travel spike recovery was obtained for bromomethane (62%). Blank values for all compounds were either below detection or very low. Ambient atmospheric sampling was conducted in New Jersey from April to December, 1997. Three sites characterized by low, moderate, and high densities of urbanization/traffic were sampled. The median detected concentrations of the compounds were either similar at all three sites (as with the chlorofluorocarbon compounds) or increased with the density of urbanization/traffic (as with dichloromethane, MTBE, benzene, and toluene). For toluene, the median detected

  13. Survival and growth of Alfalfa (Medicago sativa l.) inoculated with an am fungus (Glomus intraradices) in contaminated soils treated with two different remediation technologies (bio-pile and thermal desorption)

    Energy Technology Data Exchange (ETDEWEB)

    Norini, M.P.; Beguiristain, Th.; Leyval, C. [LIMOS UMR 7137 CNRS-UHP Nancy - Faculty of Sciences, 54 - Vandoeuvre-les-Nancy (France)

    2005-07-01

    Polycyclic aromatic hydrocarbons (PAHs) represent a group of persistent and toxic soil pollutants that are of major public concern due to their mutagenic and carcinogenic property. Phyto-remediation is the use of plants and their associated microorganisms for remediation of polluted soils. Phyto-remediation could be used in conjunction with other remediation technologies to reduce the contamination to safe levels and maintain or restore soil physico-chemical and biological properties. Most plant species form mycorrhizas with symbiotic fungi. It was shown that AM fungi enhance survival and plant growth in PAH contaminated soils. Mycorrhizal fungi also enhance the biotransformation or biodegradation of PAH, although the effect differed between soils. A rhizosphere and myco-rhizosphere gradient of PAH concentrations was observed, with decreased PAH concentration with decreased distance to roots. Different microbial communities were found in the rhizosphere of AM and non-mycorrhizal plants in comparison to bulk soil, suggesting that AM could affect PAH degradation by changing microbial communities. We investigated the effect of mycorrhizal fungi and nutrients on the ability of alfalfa to grow on soil contaminated with PAHs before and after two remediation treatments. We used soil from an industrial site (Homecourt, North East part of France) highly contaminated with PAH (2000 mg kg{sup -1}), which has been partially treated by two different remediation technologies (bio-pile and thermal desorption). The bio-pile treatment consisted of piling the contaminated soil with stimulation of aerobic microbial activity by aeration and addition of nutrient solution, and reduced PAH concentration to around 300 mg kg-1. With the thermal desorption treatment the soil was heated to around 500 deg. C so that PAH vaporized and were separated from the soil. The residual PAH concentration in soil was 40 mg kg{sup -1}. Treated and non-treated contaminated soil was planted with alfalfa

  14. Surface modification of tungsten and tungsten-tantalum alloys exposed to high-flux deuterium plasma and its impact on deuterium retention

    NARCIS (Netherlands)

    Zayachuk, Y.; Hoen, M. H. J. 't; van Emmichoven, P. A. Zeijlma; Terentyev, D.; Uytdenhouwen, I.; Van Oost, G.

    2013-01-01

    Samples of tungsten and tungsten-tantalum alloy (with 5 mass per cent of Ta) were exposed to high-flux deuterium plasma at different fluences. The surface modification was studied with scanning electron microscopy, and deuterium retention was measured by thermal desorption spectroscopy (TDS). In the

  15. Continuous soil VOCl measurements with automated flux chambers and micro-ECD gas chromatography coupled with the thermal desorption and cooled injection systems

    Science.gov (United States)

    Molodovskaya, M. S.; Svensson, T.; Pitts, A.; Delmonte, J.; Nesic, Z.; Oberg, G.

    2010-12-01

    automated chamber was continuously pumped through the glass tubes filled with carbon-based absorbent (Carbotrap 300) to capture and retain VOCl. At the end of each measurement period, the tubes are brought back to the lab, and the content is analyzed by Agilent 7890 GC/micro-ECD coupled with the Gerstel Thermal Desorption System (TDS) and Cooled Injection System (CIS). The ultra sensitive micro-ECD detection and high-efficiency capillary column (Rtx®-VMS, 20m x 0.18mm ID x 1.0µm) allows rapid separation and quantification of the mid-weight VOCl such as chloroform, carbon tetrachloride, 1,1,1-trichloroethane and bromochloromethane. The GC-method dynamic range is linear within 0.1-200.0ng, and the analytical precision is determined to be 4%. The described system can be used for the analysis of soil/atmosphere exchange of VOCl at the detection limit of 1.9ng m-2 h-1, which is far below previously reported average soil emission levels from forest soils. The high precision GC analysis combined with the automatic chambers makes it possible to study the high spatial and temporal variability of soil VOCl fluxes.

  16. Ultra-fast cyclosporin A quantitation in whole blood by Laser Diode Thermal Desorption-tandem mass spectrometry; comparison with High Performance Liquid Chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Jourdil, Jean-François; Picard, Pierre; Meunier, Cécile; Auger, Serge; Stanke-Labesque, Françoise

    2013-12-17

    In the last decade the quantitation of immunosuppressive drugs has seen vast improvements in analytical methods, optimizing time, accuracy of analysis and cost. Laser Diode Thermal Desorption (LDTD) coupled to Atmospheric Pressure Chemical ionization-tandem mass spectrometry (APCI-MS/MS) represents a technological breakthrough that removes the chromatographic separation step and thereby significantly increases the analytical throughput for the quantitation of cyclosporin A (CsA) in whole blood for therapeutic drug monitoring (TDM). A simple protein precipitation step was used prior to depositing 5 μL of the extract on a 96-well LazWell™ plate and CsA was quantified by LDTD-APCI-MS/MS. The laser pattern was set to ramp from 0 to 45% laser power within 2 s. The APCI parameters were set to negative needle voltage (-2 μA), carrier gas temperature (30°C) and air flow rate (3 L min(-1)). The negative ion single reaction monitoring transitions for CsA and its internal standard cyclosporin D (CsD) were respectively m/z 1201.1/1088.9 and m/z 1214.8/1102.8; obtained with a collision energy of -40 V. The analysis was achieved within 9 s from sample to sample. The extraction procedure yielded high recovery (92%; RSD=9.4%, n=6). The lower limit of quantitation was fixed at the first level of calibration: 23.5 ng mL(-1) (accuracy=112.3%; RSD=9.6%; n=6) and a blank+6 point linear regression up to 965 ng mL(-1) was used. Using 4 levels of quality control (QC), intra-day assays (n=6) ranged from 93.5 to 95.7% (bias) and from 3.4 to 13.1% (RSD) while inter-day assays (n=6) ranged from 92.9 to 105.3% (bias) and from 4.9 to 7.5% (RSD). An inter-sample contamination of CsA of 2.3% was calculated that was considered negligible with respect to the range of CsA concentrations. Whole blood samples (120) from patients under CsA treatment were analyzed by LDTD-APCI-MS/MS and HPLC-ESI-MS/MS, the gold standard reference method for CsA quantification. Both methods agreed (P≥0.99), with a

  17. Determination of phosphine and other fumigants in air samples by thermal desorption and 2D heart-cutting gas chromatography with synchronous SIM/Scan mass spectrometry and flame photometric detection.

    Science.gov (United States)

    Fahrenholtz, Svea; Hühnerfuss, Heinrich; Baur, Xaver; Budnik, Lygia Therese

    2010-12-24

    Fumigants and volatile industrial chemicals are particularly hazardous to health when a freight container is fumigated or the contaminated material is introduced into its enclosed environment. Phosphine is now increasingly used as a fumigant, after bromomethane--the former fumigant of choice--has been banned by the Montreal Protocol. We have enhanced our previously established thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) method by integrating a second gas chromatographic dimension and a flame photometric detector to allow the simultaneous detection of phosphine and volatile organic compounds (VOCs), providing a novel application. A thermal desorption system is coupled to a two dimensional gas chromatograph using both mass spectrometric and flame photometric detection (TD-2D-GC-MS/FPD). Additionally, the collection of mass spectrometric SIM and Scan data has been synchronised, so only a single analysis is now sufficient for qualitative scanning of the whole sample and for sensitive quantification. Though detection limits for the herewith described method are slightly higher than in the previous method, they are in the low μL m(-3) range, which is not only below the respective occupational exposure and intervention limits but also allows the detection of residual contamination after ventilation. The method was developed for the separation and identification of 44 volatile substances. For 12 of these compounds (bromomethane, iodomethane, dichloromethane, 1,2-dichlorethane, benzene, tetrachloromethane, 1,2-dichloropropane, toluene, trichloronitromethane, ethyl benzene, phosphine, carbon disulfide) the method was validated as we chose the target compounds due to their relevance in freight container handling.

  18. Highly hydrogen-sensitive thermal desorption spectroscopy system for quantitative analysis of low hydrogen concentration (∼1 × 10(16) atoms/cm(3)) in thin-film samples.

    Science.gov (United States)

    Hanna, Taku; Hiramatsu, Hidenori; Sakaguchi, Isao; Hosono, Hideo

    2017-05-01

    We developed a highly hydrogen-sensitive thermal desorption spectroscopy (HHS-TDS) system to detect and quantitatively analyze low hydrogen concentrations in thin films. The system was connected to an in situ sample-transfer chamber system, manipulators, and an rf magnetron sputtering thin-film deposition chamber under an ultra-high-vacuum (UHV) atmosphere of ∼10(-8) Pa. The following key requirements were proposed in developing the HHS-TDS: (i) a low hydrogen residual partial pressure, (ii) a low hydrogen exhaust velocity, and (iii) minimization of hydrogen thermal desorption except from the bulk region of the thin films. To satisfy these requirements, appropriate materials and components were selected, and the system was constructed to extract the maximum performance from each component. Consequently, ∼2000 times higher sensitivity to hydrogen than that of a commercially available UHV-TDS system was achieved using H(+)-implanted Si samples. Quantitative analysis of an amorphous oxide semiconductor InGaZnO4 thin film (1 cm × 1 cm × 1 μm thickness, hydrogen concentration of 4.5 × 10(17) atoms/cm(3)) was demonstrated using the HHS-TDS system. This concentration level cannot be detected using UHV-TDS or secondary ion mass spectroscopy (SIMS) systems. The hydrogen detection limit of the HHS-TDS system was estimated to be ∼1 × 10(16) atoms/cm(3), which implies ∼2 orders of magnitude higher sensitivity than that of SIMS and resonance nuclear reaction systems (∼10(18) atoms/cm(3)).

  19. Effects of soil particle size and organic matter content on thermal desorption of polybrominated diphenyl ether%土壤粒径及有机质对多溴二苯醚热脱附的影响

    Institute of Scientific and Technical Information of China (English)

    傅海辉; 黄启飞; 朱晓华; 何洁; 唐振武; 孟昭福

    2013-01-01

    Under laboratory conditions,the two effect factors of soil particle size and organic matter content were studied in order to give the theory basis PBDEs of thermal desorption from contaminated soils.The results showed that the removal rates of PBDEs from different particle sizes of soils(75,75 ~ 125,125 ~ 250,250 ~425 and 425 ~ 850 μm) contaminated by PBDEs were 49.53%,73.88%,79.39%,83.56%,87.09%,respectively.The total removal rate of PBDEs increased with the particle size increasing,and BDE209 was removed more easily than BDE206,BDE207 and BDE208 from soils.In addition,the PBDEs removal rate from the soil oxidated with H2O2 was higher than that from the original soil with the same PBDEs concentration below 450℃,which showed that soil organic matter may inhibit the thermal desorption of PBDEs.%在实验室条件下,研究了土壤粒径与土壤有机质含量对多溴二苯醚(PBDEs)热脱附的影响,以期为PBDEs污染土壤热脱附修复提供理论依据.实验结果表明,300℃停留30 min条件下,粒径为<75、75~ 125、125~250、250 ~425和425~ 850 μm的土壤中PBDEs去除率分别为49.53%、73.88%、79.39%、83.56%和87.09%,PBDEs总去除率随粒径的增大而增大,土壤BDE209较BDE206、BDE207和BDE208更易于脱除.此外,温度低于450℃时,H2O2氧化部分去除有机质后土壤中PBDEs的去除率较原土高;表明,土壤有机质可能抑制土壤中PBDEs的热脱附.

  20. First field application of a thermal desorption resonance-enhanced multiphoton-ionisation single particle time-of-flight mass spectrometer for the on-line detection of particle-bound polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Oster, Markus; Elsasser, Michael; Schnelle-Kreis, Jürgen; Zimmermann, Ralf

    2011-12-01

    The on-line analysis of single aerosol particles with mass spectrometrical methods is an important tool for the investigation of aerosols. Often, a single laser pulse is used for one-step laser desorption/ionisation of aerosol particles. Resulting ions are detected with time-of-flight mass spectrometry. With this method, the detection of inorganic compounds is possible. The detection of more fragile organic compounds and carbon clusters can be accomplished by separating the desorption and the ionisation in two steps, e.g. by using two laser pulses. A further method is, using a heated metal surface for thermal desorption of aerosol particles. If an ultraviolet laser is used for ionisation, a selective ionisation of polycyclic aromatic hydrocarbons (PAH) and alkylated PAH is possible via a resonance-enhanced multiphoton-ionisation process. Laser velocimetry allows individual laser triggering for single particles and additionally delivers information on aerodynamic particle diameters. It was shown that particles deriving from different combustion sources can be differentiated according to their PAH patterns. For example, retene, a C(4)-alkylated phenanthrene derivative, is a marker for the combustion of coniferous wood. In this paper, the first field application of a thermal desorption resonance-enhanced multiphoton-ionisation single particle time-of-flight mass spectrometer during a measurement campaign in Augsburg, Germany in winter 2010 is presented. Larger PAH-containing particles (i.e. with aerodynamic diameters larger than 1 μm), which are suspected to be originated by re-suspension processes of agglomerated material, were in the focus of the investigation. Due to the low concentration of these particles, an on-line virtual impactor enrichment system was used. The detection of particle-bound PAH in ambient particles in this larger size region was possible and in addition, retene could be detected on several particles, which allows to identify wood combustion as

  1. Co-Creation

    DEFF Research Database (Denmark)

    Degnegaard, Rex

    2012-01-01

    Co-creation as a concept has won terrain over the past 10 years. In practice as well as in literature, co-creation is climbing the agenda in relation to contemporary opportunities and challenges within management, organization development, and change initiatives. However, there Is very little...... research-based literature on the development of co-creation. This paper aims to build an overview of the literature on co-creation to explore what the existing literature relate to and indeed to pinpoint if any pattern or streams can be identified. A main finding from the analysis is how co-creation tends...

  2. Co-Creation

    DEFF Research Database (Denmark)

    Degnegaard, Rex

    Co-creation as a concept has won terrain over the past 10 years. In practice as well as in literature, co-creation is climbing the agenda in relation to contemporary opportunities and challenges within management, organization development, and change initiatives. However, there Is very little...... research-based literature on the development of co-creation. This paper aims to build an overview of the literature on co-creation to explore what the existing literature relate to and indeed to pinpoint if any pattern or streams can be identified. A main finding from the analysis is how co-creation tends...

  3. Analysis of volatile organic compounds released from the decay of surrogate human models simulating victims of collapsed buildings by thermal desorption-comprehensive two-dimensional gas chromatography-time of flight mass spectrometry.

    Science.gov (United States)

    Agapiou, A; Zorba, E; Mikedi, K; McGregor, L; Spiliopoulou, C; Statheropoulos, M

    2015-07-01

    Field experiments were devised to mimic the entrapment conditions under the rubble of collapsed buildings aiming to investigate the evolution of volatile organic compounds (VOCs) during the early dead body decomposition stage. Three pig carcasses were placed inside concrete tunnels of a search and rescue (SAR) operational field terrain for simulating the entrapment environment after a building collapse. The experimental campaign employed both laboratory and on-site analytical methods running in parallel. The current work focuses only on the results of the laboratory method using thermal desorption coupled to comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (TD-GC×GC-TOF MS). The flow-modulated TD-GC×GC-TOF MS provided enhanced separation of the VOC profile and served as a reference method for the evaluation of the on-site analytical methods in the current experimental campaign. Bespoke software was used to deconvolve the VOC profile to extract as much information as possible into peak lists. In total, 288 unique VOCs were identified (i.e., not found in blank samples). The majority were aliphatics (172), aromatics (25) and nitrogen compounds (19), followed by ketones (17), esters (13), alcohols (12), aldehydes (11), sulfur (9), miscellaneous (8) and acid compounds (2). The TD-GC×GC-TOF MS proved to be a sensitive and powerful system for resolving the chemical puzzle of above-ground "scent of death".

  4. Characterisation of the flavour profile from Graciano Vitis vinifera wine variety by a novel dual stir bar sorptive extraction methodology coupled to thermal desorption and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Arbulu, Maria; Sampedro, M Carmen; Sanchez-Ortega, Alicia; Gómez-Caballero, Alberto; Unceta, Nora; Goicolea, M Aranzazu; Barrio, Ramón J

    2013-05-13

    The aim of this work was to develop a new analytical technique for the study of the organoleptic compounds (flavour profile) of the Graciano Vitis vinifera wine variety. The cv. Graciano is a singular variety of red grapes with its origins in La Rioja and Navarra (northern Spain). This variety transfers an intense red colour, aroma and high acidity to musts and provides greater longevity and, consequently, a better capacity for ageing wine. A new dual-stir bar sorptive extraction approach coupled with thermal desorption (TD) and GC-MS has been used to extract the volatile and semivolatile compounds. In this extraction step, the optimal values for the experimental variables were obtained through the Response Surface Methodology (RSM). Full scan chromatogram data were evaluated with two deconvolution software tools, and the results were compared. The volatile and semivolatile components were identified with an MS match ≥80%. As a result, the flavour metabolome of the Graciano Vitis vinifera wine variety was obtained, and 205 metabolites were identified using different databases. These metabolites were grouped into esters, acids, alcohols, nitrogen compounds, furans, lactones, ketones, aldehydes, phenols, terpenes, norisoprenoids, sulphur compounds, acetals and pyrans. The majority of the metabolites observed had already been reported in the literature; however, this work also identified new, previously unreported metabolites in red wines, which may be characteristic of the Graciano variety. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Fast and solvent-free quantitation of boar taint odorants in pig fat by stable isotope dilution analysis-dynamic headspace-thermal desorption-gas chromatography/time-of-flight mass spectrometry.

    Science.gov (United States)

    Fischer, Jochen; Haas, Torsten; Leppert, Jan; Lammers, Peter Schulze; Horner, Gerhard; Wüst, Matthias; Boeker, Peter

    2014-09-01

    Boar taint is a specific off-odour of boar meat products, known to be caused by at least three unpleasant odorants, with very low odour thresholds. Androstenone is a boar pheromone produced in the testes, whereas skatole and indole originate from the microbial breakdown of tryptophan in the intestinal tract. A new procedure, applying stable isotope dilution analysis (SIDA) and dynamic headspace-thermal desorption-gas chromatography/time-of-flight mass spectrometry (dynHS-TD-GC/TOFMS) for the simultaneous quantitation of these boar taint compounds in pig fat was elaborated and validated in this paper. The new method is characterised by a simple and solvent-free dynamic headspace sampling. The deuterated compounds d3-androstenone, d3-skatole and d6-indole were used as internal standards to eliminate matrix effects. The method validation performed revealed low limits of detection (LOD) and quantitation (LOQ) with high accuracy and precision, thus confirming the feasibility of the new dynHS-TD-GC/TOFMS approach for routine analysis.

  6. Determination of 1-chloro-4-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]benzene and related compounds in marine pore water by automated thermal desorption-gas chromatography/mass spectrometry using disposable optical fiber

    Science.gov (United States)

    Eganhouse, Robert P.; DiFilippo, Erica L

    2015-01-01

    A method is described for determination of ten DDT-related compounds in marine pore water based on equilibrium solid-phase microextraction (SPME) using commercial polydimethylsiloxane-coated optical fiber with analysis by automated thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS). Thermally cleaned fiber was directly exposed to sediments and allowed to reach equilibrium under static conditions at the in situ field temperature. Following removal, fibers were rinsed, dried and cut into appropriate lengths for storage in leak-tight containers at -20°C. Analysis by TD-GC/MS under full scan (FS) and selected ion monitoring (SIM) modes was then performed. Pore-water method detection limits in FS and SIM modes were estimated at 0.05-2.4ng/L and 0.7-16pg/L, respectively. Precision of the method, including contributions from fiber handling, was less than 10%. Analysis of independently prepared solutions containing eight DDT compounds yielded concentrations that were within 6.9±5.5% and 0.1±14% of the actual concentrations in FS and SIM modes, respectively. The use of optical fiber with automated analysis allows for studies at high temporal and/or spatial resolution as well as for monitoring programs over large spatial and/or long temporal scales with adequate sample replication. This greatly enhances the flexibility of the technique and improves the ability to meet quality control objectives at significantly lower cost.

  7. Determination of trichloromethane in workplace air by thermal desorption-gas chromatography%工作场所空气中三氯甲烷的热脱附气相色谱联用测定法

    Institute of Scientific and Technical Information of China (English)

    刘浏; 胡晓宇; 庞平; 傅佳; 钟磊

    2013-01-01

    To establish a method for determination of trichloromethane in workplace air by thermal desorption-gas chromatography.[Methods] The trichloromethane samples were collected from workplace air by Air Toxics adsorption tube,injection was conducted after desorption with Pekin Elmer Tubo Matrix AFD 650 thermal desorption instrument,and detection was performed by flame ionization detector.The retention time was adopted in qualitative analysis,and peak area was applied in quantitative evaluation.The laboratory examination and simulate experiments were conducted according to the Determination methods of air chemicals in workplace.[Results] The standard curve was linear in the content ranges of 0-300 μl,and the regression equation was Y =16.6 X + 2.8,r =1.000.The detection limit was 0.88 μg.The minimum detectable concentration was 0.20 mg/m3 while the sampling volume was 4.5 L.The repeatability was good,the relative standard deviation (RSD) was 3.14%-6.15%,the desorption efficiency was 103.0%-83.7%,and the sampling efficiency was 100%.The samples could be stably stored for 3 days in Air Toxics adsorption tube.[Conclusion] The method is simple and rapid,with high sensitivity,which is suitable for determination of trichloromethane in workplace air.%目的 建立测定工作场所空气中三氯甲烷的热脱附-气相色谱联用检测方法.方法 工作场所空气中的三氯甲烷用Air Toxics吸附管采样,用Pekin Elmer Tubo Matrix ATD-650热脱附仪脱附后进样,经毛细管色谱柱分离,氢火焰离子化检测器检测,以保留时间定性,峰面积定量.方法研究按照《工作场所空气中化学物质测定方法》的要求进行实验室实验及模拟现场实验.结果 该方法在0 ~ 300μl范围内呈线性关系,峰面积与含量的回归方程为Y=16.6X +2.8;r=1.000;检出限为0.88μg,当采样体积为4.5L时最低检出浓度为0.20 mg/m3;方法的重现性较好,不同浓度的相对标准偏差为3.14% ~6,15

  8. Analysis of the Volatile Organic Components in Malus hupenhensis Rehd Leaves by Direct Thermal Desorption Gas Chromatography-mass Spectrometry%湖北海棠叶挥发性成分的 DTD-GC/MS 分析∗

    Institute of Scientific and Technical Information of China (English)

    王宵; 杜业云; 杨志斌; 李晖; 杨柳

    2015-01-01

    The method of direct thermal desorption (DTD)combed with gas chromatography-mass spectrometry (GC/MS)was applied to analyze the volatile organic components in leaves of Malus hupenhensis for the first time,and 46 kinds of volatile organic components were identified.The main chemical components were hydrocarbons,esters,alcohols,ke-tones,vinyl,aldehydes and so on.8 kinds of components can be used as spice additives,5 types can be used for medical purposes,2 kinds can be used as insecticides.This method of analyzing Malus hupenhensis leaves components had good re-peatability,and was simple,efficient,sensitive and environment-friendly.%采用直接热脱附—气相色谱/质谱联用技术(DTD-GC/MS)首次分析了湖北海棠叶挥发性成分,共检测鉴定出有效成分46种,主要包括烷烃类、酯类、醇类、酮类、烯类、醛类等化合物。其中,8种可用作香料添加剂,5种可作医疗用途,2种可用于杀虫剂。采用直接热脱附—气相色谱/质谱法分析湖北海棠叶挥发成分重现性好、操作简单、效率高、绿色环保。

  9. Development of a Method for the Quantitation of Three Thiols in Beer, Hop, and Wort Samples by Stir Bar Sorptive Extraction with in Situ Derivatization and Thermal Desorption-Gas Chromatography-Tandem Mass Spectrometry.

    Science.gov (United States)

    Ochiai, Nobuo; Sasamoto, Kikuo; Kishimoto, Toru

    2015-08-05

    A method for analysis of hop-derived polyfunctional thiols, such as 4-sulfanyl-4-methylpentan-2-one (4S4M2Pone), 3-sulfanylhexan-1-ol (3SHol), and 3-sulfanylhexyl acetate (3SHA), in beer, hop water extract, and wort at nanogram per liter levels was developed. The method employed stir bar sorptive extraction with in situ derivatization (der-SBSE) using ethyl propiolate (ETP), followed by thermal desorption and gas chromatography-tandem mass spectrometry (TD-GC-MS/MS) with selected reaction monitoring (SRM) mode. A prior step involved structural identification of the ETP derivatives of the thiols by TD-GC-quadrupole-time-of-flight mass spectrometry with parallel sulfur chemiluminescence detection (Q-TOF-MS/SCD) after similar der-SBSE. The der-SBSE conditions of the ETP concentration, buffer concentration, salt addition, and extraction time profiles were investigated, and the performance of the method was demonstrated with spiked beer samples. The limits of detection (LODs) (0.19-27 ng/L) are below the odor threshold levels of all analytes. The apparent recoveries at 10-100 ng/L (99-101%) and the repeatabilities [relative standard deviation (RSD) of 1.3-7.2%; n = 6] are also good. The method was successfully applied to the determination of target thiols at nanogram per liter levels in three kinds of beer samples (hopped with Cascade, Citra, and Nelson Sauvin) and the corresponding hop water extracts and wort samples. There was a clear correlation between the determined values and the characteristics of citrus hop aroma for each sample.

  10. Development of a new multi-residue laser diode thermal desorption atmospheric pressure chemical ionization tandem mass spectrometry method for the detection and quantification of pesticides and pharmaceuticals in wastewater samples.

    Science.gov (United States)

    Boisvert, Michel; Fayad, Paul B; Sauvé, Sébastien

    2012-11-19

    A new solid phase extraction (SPE) method coupled to a high throughput sample analysis technique was developed for the simultaneous determination of nine selected emerging contaminants in wastewater (atrazine, desethylatrazine, 17β-estradiol, ethynylestradiol, norethindrone, caffeine, carbamazepine, diclofenac and sulfamethoxazole). We specifically included pharmaceutical compounds from multiple therapeutic classes, as well as pesticides. Sample pre-concentration and clean-up was performed using a mixed-mode SPE cartridge (Strata ABW) having both cation and anion exchange properties, followed by analysis by laser diode thermal desorption atmospheric pressure chemical ionization coupled to tandem mass spectrometry (LDTD-APCI-MS/MS). The LDTD interface is a new high-throughput sample introduction method, which reduces total analysis time to less than 15s per sample as compared to minutes with traditional liquid-chromatography coupled to tandem mass spectrometry (LC-MS/MS). Several SPE parameters were evaluated in order to optimize recovery efficiencies when extracting analytes from wastewater, such as the nature of the stationary phase, the loading flow rate, the extraction pH, the volume and composition of the washing solution and the initial sample volume. The method was successfully applied to real wastewater samples from the primary sedimentation tank of a municipal wastewater treatment plant. Recoveries of target compounds from wastewater ranged from 78% to 106%, the limit of detection ranged from 30 to 122ng L(-1) while the limit of quantification ranged from 90 to 370ng L(-1). Calibration curves in the wastewater matrix showed good linearity (R(2)≥0.991) for all target analytes and the intraday and interday coefficient of variation was below 15%, reflecting a good precision.

  11. Diclofenac in municipal wastewater treatment plant: quantification using laser diode thermal desorption--atmospheric pressure chemical ionization--tandem mass spectrometry approach in comparison with an established liquid chromatography-electrospray ionization-tandem mass spectrometry method.

    Science.gov (United States)

    Lonappan, Linson; Pulicharla, Rama; Rouissi, Tarek; Brar, Satinder K; Verma, Mausam; Surampalli, Rao Y; Valero, José R

    2016-02-12

    Diclofenac (DCF), a prevalent non-steroidal anti-inflammatory drug (NSAID) is often detected in wastewater and surface water. Analysis of the pharmaceuticals in complex matrices is often laden with challenges. In this study a reliable, rapid and sensitive method based on laser diode thermal desorption/atmospheric pressure chemical ionization (LDTD/APCI) coupled with tandem mass spectrometry (MS/MS) has been developed for the quantification of DCF in wastewater and wastewater sludge. An established conventional LC-ESI-MS/MS (liquid chromatography-electrospray ionization-tandem mass spectrometry) method was compared with LDTD-APCI-MS/MS approach. The newly developed LDTD-APCI-MS/MS method reduced the analysis time to 12s in lieu of 12 min for LC-ESI-MS/MS method. The method detection limits for LDTD-APCI-MS/MS method were found to be 270 ng L(-1) (LOD) and 1000 ng L(-1) (LOQ). Furthermore, two extraction procedures, ultrasonic assisted extraction (USE) and accelerated solvent extraction (ASE) for the extraction of DCF from wastewater sludge were compared and ASE with 95.6 ± 7% recovery was effective over USE with 86 ± 4% recovery. The fate and partitioning of DCF in wastewater (WW) and wastewater sludge (WWS) in wastewater treatment plant was also monitored at various stages of treatment in Quebec Urban community wastewater treatment plant. DCF exhibited affinity towards WW than WWS with a presence about 60% of DCF in WW in contrary with theoretical prediction (LogKow=4.51).

  12. Development and validation of a method for air-quality and nuisance odors monitoring of volatile organic compounds using multi-sorbent adsorption and gas chromatography/mass spectrometry thermal desorption system.

    Science.gov (United States)

    Ribes, Alejandra; Carrera, Guillem; Gallego, Eva; Roca, Xavier; Berenguer, M A José; Guardino, Xavier

    2007-01-26

    An analytical method based on thermal desorption (TD) coupled to gas chromatography (GC) and mass spectrometry detection (MS) has been developed and validated for the determination of a wide range of odor nuisance and air-quality volatile organic compounds (VOC) in air. New generation isocyanates, isocyanato- and isothiocyanatocyclohexane, have been included for the first time as target compounds due to their high occurrence in air samples. A dynamic air sampling method to trap gas and vapor on multi-sorbent tubes using portable pump equipment has been also developed. Sorbent tubes were filled with Carbotrap (70mg), Carbopack X (100mg) and Carboxen-569 (90mg). Validation of the TD-GC-MS method showed good selectivity, sensibility and precision according to Compendium Method TO-17 (US Environment Protection Agency) criteria. Limits of detection (signal-to-noise=3, ng in tube) ranges were 0.004-0.03ng (alcanes), 0.001-0.1ng (aromatics), 0.03-14ng (aldehydes), 0.003-7ng (alcohols), 0.003-0.04ng (chlorides), 0.02-0.5ng (esters), 0.002-0.1ng (ketones), 0.01-0.53ng (terpenes), 14-97ng (amides), 0.2-10ng (isocyanates) and 0.001ng (carbon disulfide). The linear dynamic range was over 3-5 orders of magnitude, depending of the VOC. TD-GC-MS analysis was reproducible, with relative standard deviation (n=5) within 20%. VOCs breakthrough examination showed no significant losses when about 2000ng standard was prepared. In order to evaluate the performance of the developed method on real samples, several industrial and urban air samples were analysed. VOCs were found to be stable on the sorbent tubes for at least 1 week when stored at 4 degrees C.

  13. Monitoring of PAHs in air by collection on XAD-2 adsorbent then microwave-assisted thermal desorption coupled with headspace solid-phase microextraction and gas chromatography with mass spectrometric detection.

    Science.gov (United States)

    Wei, Ming-Chi; Chang, Wan-Ting; Jen, Jen-Fon

    2007-02-01

    Microwave-assisted thermal desorption (MAD) coupled to headspace solid-phase microextraction (HS-SPME) has been studied for in-situ, one-step, sample preparation for PAHs collected on XAD-2 adsorbent, before gas chromatography with mass spectrometric detection. The PAHs on XAD-2 were desorbed into the extraction solution, evaporated into the headspace by use of microwave irradiation, and absorbed directly on a solid-phase microextraction fiber in the headspace. After desorption from the SPME fiber in the hot GC injection port, PAHs were analyzed by GC-MS. Conditions affecting extraction efficiency, for example extraction solution, addition of salt, stirring speed, SPME fiber coating, sampling temperature, microwave power and irradiation time, and desorption conditions were investigated. Experimental results indicated that extraction of 275 mg XAD-2, containing 10-200 ng PAHs, with 10-mL ethylene glycol-1 mol L(-1) NaCl solution, 7:3, by irradiation with 120 W for 40 min (the same as the extraction time), and collection with a PDMS-DVB fiber at 35 degrees C, resulted in the best extraction efficiency. Recovery was more than 80% and RSD was less than 14%. Optimum desorption was achieved by heating at 290 degrees C for 5 min. Detection limits varied from 0.02 to 1.0 ng for different PAHs. A real sample was obtained by using XAD-2 to collect smoke from indoor burning of joss sticks. The amounts of PAHs measured varied from 0.795 to 2.53 ng. The method is a simple and rapid procedure for determination of PAHs on XAD-2 absorbent, and is free from toxic organic solvents.

  14. Creationism in Europe

    DEFF Research Database (Denmark)

    antievolutionism in countries and religions throughout Europe. Providing a unique map of creationism in Europe, the authors chart the surprising history of creationist activities and strategies there. Over the past forty years, creationism has spread swiftly among European Catholics, Protestants, Jews, Hindus...

  15. Thermal desorption of deuterium implanted into beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Markin, A.V.; Chernikov, V.N.; Zakharov, A.P. [Institute of Physical Chemistry, Moscow (Russian Federation)] [and others

    1995-09-01

    By means of TDS measurements it is shown that the desorption of deuterium from Be implanted with 5 keV D ions to fluences, {Phi}, from 1x10{sup 20} D/m{sup 2} to 1x10{sup 21} D/m{sup 2} proceeds in one high temperature stage B, while at {Phi} {ge} 1.2x10{sup 21}D/m{sup 2} one more stage A is added. The desorption maximum A is narrow and consists of two peaks A{sub 1} and A{sub 2} at about 460 K and 490 K, respectively. Peak A{sub 1} is attributed to the desorption of deuterium from the walls of opened channels formed under D ion implantation. Peak {sub A}2 is a consequence of the opening of a part of closed bubbles/channels to the outer surface. The position of maximum B shifts noticeably and nonsteadily on the fluence in a range from 850 to 1050 K. The origin of this maximum is the liberation of D atoms bound at vacancy complexes discussed previously by Wampler. The dependence of Tm(B) on the fluence is governed by the interaction of freely migrating D atoms with partly opened or fully closed gas cavity arrangements which are created under temperature ramping, but differently in specimens implanted with D ions to different fluences.

  16. The creation of strongly coupled plasmas using an intense heavy ion beam: low-entropy compression of hydrogen and the problem of hydrogen metallization

    CERN Document Server

    Tahir, N A; Shutov, A; Varentsov, D; Udrea, S; Hoffmann, Dieter H H; Juranek, H; Redmer, R; Portugues, R F; Lomonosov, I V; Fortov, V E

    2003-01-01

    Intense heavy ion beams deposit energy very efficiently over extended volumes of solid density targets, thereby creating large samples of strongly coupled plasmas. Intense beams of energetic heavy ions are therefore an ideal tool to research this interesting field. It is also possible to design experiments using special beam-target geometries to achieve low-entropy compression of samples of matter. This type of experiments is of particular interest for studying the problem of hydrogen metallization. In this paper we present a design study of such a proposed experiment that will be carried out at the future heavy ion synchrotron facility SIS100, at the Gesellschaft fuer Schwerionenforschung, Darmstadt. This study has been done using a two-dimensional hydrodynamic computer code. The target consists of a solid hydrogen cylinder that is enclosed in a thick shell of lead whose one face is irradiated with an ion beam which has an annular (ring shaped) focal spot. The beam intensity and other parameters are consider...

  17. The creation of strongly coupled plasmas using an intense heavy ion beam: low-entropy compression of hydrogen and the problem of hydrogen metallization

    Energy Technology Data Exchange (ETDEWEB)

    Tahir, N A [Institut fuer Theoretische Physik, Universitaet Frankfurt, Postfach 11 19 32, 60054 Frankfurt (Germany); Piriz, A R [ETSI Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Shutov, A [Institute for Problems in Chemical Physics Research, Chernogolovka, Russia (Russian Federation); Varentsov, D [Institut fuer Kernphysik, Technische Universitaet Darmstadt, Schlossgarten Str. 9, 64289 Darmstadt (Germany); Udrea, S [Institut fuer Kernphysik, Technische Universitaet Darmstadt, Schlossgarten Str. 9, 64289 Darmstadt (Germany); Hoffmann, D H H [Institut fuer Kernphysik, Technische Universitaet Darmstadt, Schlossgarten Str. 9, 64289 Darmstadt (Germany); Juranek, H [Fachbereich Physik, Universitaet Rostock, 18051 Rostock (Germany); Redmer, R [Fachbereich Physik, Universitaet Rostock, 18051 Rostock (Germany); Portugues, R F [ETSI Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Lomonosov, I [Institute for Problems in Chemical Physics Research, Chernogolovka, Russia (Russian Federation); Fortov, V E [Institute for Problems in Chemical Physics Research, Chernogolovka, Russia (Russian Federation)

    2003-06-06

    Intense heavy ion beams deposit energy very efficiently over extended volumes of solid density targets, thereby creating large samples of strongly coupled plasmas. Intense beams of energetic heavy ions are therefore an ideal tool to research this interesting field. It is also possible to design experiments using special beam-target geometries to achieve low-entropy compression of samples of matter. This type of experiments is of particular interest for studying the problem of hydrogen metallization. In this paper we present a design study of such a proposed experiment that will be carried out at the future heavy ion synchrotron facility SIS100, at the Gesellschaft fuer Schwerionenforschung, Darmstadt. This study has been done using a two-dimensional hydrodynamic computer code. The target consists of a solid hydrogen cylinder that is enclosed in a thick shell of lead whose one face is irradiated with an ion beam which has an annular (ring shaped) focal spot. The beam intensity and other parameters are considered to be the same as expected at the future SIS100 facility. The simulations show that due to multiple shock reflection between the cylinder axis and the lead-hydrogen boundary, one can achieve up to 20 times solid density in hydrogen while keeping the temperature as low as a few thousand K. The corresponding pressure is of the order of 10 Mbar. These values of the physical parameters lie within the range of theoretically predicted values for hydrogen metallization. We have also carried out a parameter study of this problem by varying the target and beam parameters over a wide range. It has been found that the results are very insensitive to such changes in the input parameters.

  18. CREATION OF PAKISTAN

    OpenAIRE

    Sindhu, Shakila Noor

    2017-01-01

    Creation of a country is not an ordinary situation. But creation of Pakistan is an exception in the world history. This is one of the most debated topics in the subcontinent's socioeconomic, literature, art and political realm. Scores of researchers have investigated this extraordinary historical development in a diversity of perspectives and paradigms. Variety of exogenous and endogenous factors and a range of variables that acted, reacted and interacted among each other are evaluated. ...

  19. Creationism in Europe

    DEFF Research Database (Denmark)

    Hjermitslev, Hans Henrik; Kjærgaard, Peter C.; Blancke, Stefaan

    2013-01-01

    which material is missing from the literature (the “gaps”) and signal which gaps we think should first be filled. Third, on the basis of a forthcoming international historical study, we outline the possible factors that affect the popularity of creationism in Europe (the “prospects”). We also sketch how...... a sustained study of European creationism can contribute to other research domains such as the study of cultural evolution and the relation between science and religion....

  20. Thermal desorption-multiphoton ionization time-of-flight mass spectrometry of individual aerosol particles: a simplified approach for online single-particle analysis of polycyclic aromatic hydrocarbons and their derivatives.

    Science.gov (United States)

    Bente, Matthias; Sklorz, Martin; Streibel, Thorsten; Zimmermann, Ralf

    2009-04-01

    Online single-particle (SP) laser mass spectrometry (MS) is an important tool for fundamental and applied aerosol research. Usually laser desorption/ionization (LDI) is applied for ablation and ionization of atoms and molecular fragments from the nanometer- or micrometer-sized air-borne particles and time-of-flight analysers (TOFMS) are used for mass-selective detection of mainly inorganic analytes. The detection of molecular organic compounds is solely possible under very special experimental conditions and extremely dependent on the particle matrix and thus limited to special applications. Very recently it was shown that by implementation of a two-step laser desorption (LD) resonance-enhanced multiphoton ionization (REMPI) postionization approach the single-particulate molecular signature of polycyclic aromatic hydrocarbons (PAH) and their derivatives can be recorded (LD-REMPI-SP-TOFMS). By this, particles from different sources could be differentiated via the patterns of specific molecular source tracers such as retene for soft wood combustion or larger PAH as indicator for gasoline car emissions. One drawback of the LD-REMPI-SP-TOFMS method in particular for field applications is, however, the necessity of operation and adjustment of two lasers. In this paper the successful implementation of a thermal desorption step in single-particle mass spectrometry is described (TD-REMPI-SP-TOFMS). After size determination by particle velocimetry, individual particles are thermally desorbed on a heated surface in the ion source of the TOFMS. Desorbed molecules are ionized subsequently by REMPI, which addresses selectively PAH and molecular trace indicators. The TD-REMPI-SP-TOFMS concept was tested with reference particles and applied for automotive exhaust and ambient monitoring. The comparison of the results with the ones obtained by the two-laser approach (LD-REMPI-SP-TOFMS) indicates that the patented TD-REMPI-SP-TOFMS technology presented here is nearly equally well

  1. Measurement of breakthrough volumes of volatile chemical warfare agents on a poly(2,6-diphenylphenylene oxide)-based adsorbent and application to thermal desorption-gas chromatography/mass spectrometric analysis.

    Science.gov (United States)

    Kanamori-Kataoka, Mieko; Seto, Yasuo

    2015-09-04

    To establish adequate on-site solvent trapping of volatile chemical warfare agents (CWAs) from air samples, we measured the breakthrough volumes of CWAs on three adsorbent resins by an elution technique using direct electron ionization mass spectrometry. The trapping characteristics of Tenax(®) TA were better than those of Tenax(®) GR and Carboxen(®) 1016. The latter two adsorbents showed non-reproducible breakthrough behavior and low VX recovery. The specific breakthrough values were more than 44 (sarin) L/g Tenax(®) TA resin at 20°C. Logarithmic values of specific breakthrough volume for four nerve agents (sarin, soman, tabun, and VX) showed a nearly linear correlation with the reciprocals of their boiling points, but the data point of sulfur mustard deviated from this linear curve. Next, we developed a method to determine volatile CWAs in ambient air by thermal desorption-gas chromatography (TD-GC/MS). CWA solutions that were spiked into the Tenax TA(®) adsorbent tubes were analyzed by a two-stage TD-GC/MS using a Tenax(®) TA-packed cold trap tube. Linear calibration curves for CWAs retained in the resin tubes were obtained in the range between 0.2pL and 100pL for sarin, soman, tabun, cyclohexylsarin, and sulfur mustard; and between 2pL and 100pL for VX and Russian VX. We also examined the stability of CWAs in Tenax(®) TA tubes purged with either dry or 50% relative humidity air under storage conditions at room temperature or 4°C. More than 80% sarin, soman, tabun, cyclohexylsarin, and sulfur mustard were recovered from the tubes within 2 weeks. In contrast, the recoveries of VX and Russian VX drastically reduced with storage time at room temperature, resulting in a drop to 10-30% after 2 weeks. Moreover, we examined the trapping efficiency of Tenax TA(®) adsorbent tubes for vaporized CWA samples (100mL) prepared in a 500mL gas sampling cylinder. In the concentration range of 0.2-2.5mg/m(3), >50% of sarin, soman, tabun, cyclohexylsarin, and HD were

  2. Deuterium trapping and surface modification of polycrystalline tungsten exposed to a high-flux plasma at high fluences

    Science.gov (United States)

    Zibrov, M.; Balden, M.; Morgan, T. W.; Mayer, M.

    2017-04-01

    Deuterium (D) retention and surface modifications of hot-rolled polycrystalline tungsten (W) exposed to a low-energy (~40 eV D‑1), high-flux (2–5  ×  1023 D m‑2 s‑1) D plasma at temperatures of ~380 K and ~1140 K to fluences up to 1.2  ×  1028 D m‑2 have been examined by using nuclear reaction analysis, thermal desorption spectroscopy, and scanning electron microscopy. The samples exposed at ~380 K exhibited various types of surface modifications: dome-shaped blister-like structures, stepped flat-topped protrusions, and various types of nanostructures. It was observed that a large fraction of the surface was covered with blisters and protrusions, but their average size and the number density showed almost no fluence dependence. The D depth distributions and total D inventories also barely changed with increasing fluence at ~380 K. A substantial amount of D was retained in the subsurface region, and thickness correlated with the depth where the cavities of blisters and protrusions were located. It is therefore suggested that defects appearing during creation of blisters and protrusions govern the D trapping in the investigated fluence range. In addition, a large number of small cracks was observed on the exposed surfaces, which can serve as fast D release channels towards the surface, resulting in a reduction of the effective D influx into the W bulk. On the samples exposed at ~1140 K no blisters and protrusions were found. However, wave-like and faceted terrace-like structures were formed instead. The concentrations of trapped D were very low (<10‑5 at. fr.) after the exposure at ~1140 K.

  3. Philosophy of creation

    Directory of Open Access Journals (Sweden)

    Devyatova S. V.

    2016-01-01

    Full Text Available This article is devoted to consideration of the main principles of the concept elaborated by the famous English scientist and Christian theologian J. Polkinghorne and directed to formation more accurate idea of Creator and creation. The basic ideas of this concept: the necessity to theology a rational approach to comprehension not only of nature and peculiarities of the universe but also of its Creator; an importance of co-ordination of the modern Christian doctrine of creation with the scientific picture of the world; the great significance of natural theology for solving propounded tasks; our universe is a complex, developing by interaction of chance and law, but at the same time well-ordered and interrelated structure; human being is a part of this structure; the act of creation is a continuing process; God express Himself through His creation; Creator is simultaneously immanent and transcendent to His creation; Creator’s actions are dependent only on His free will; Creator is not impersonal, but rational, loving and suffering; Creator presented universe with an ability to self-development and human being with free will; realization of this self-development is accompanied by unpredictable consequences which are unknown not only for man, but for Creator also; God only of His own free will realized a self-limitation of His omnipotence because He loves human beings; one of our main tasks is to learn how to use our superior value - our freedom.

  4. Money creation and destruction

    OpenAIRE

    Faure, Salomon; Gersbach, Hans

    2016-01-01

    We study money creation and destruction in today’s monetary architecture and examine the impact of monetary policy and capital regulation in a general equilibrium setting. There are two types of money created and destructed: bank deposits, when banks grant loans to firms or to other banks and central bank money, when the central bank grants loans to private banks. We show that equilibria yield the first-best level of money creation and lending when prices are flexible, regardless of the monet...

  5. Particle balance in long duration RF driven plasmas on QUEST

    Energy Technology Data Exchange (ETDEWEB)

    Hanada, K., E-mail: hanada@triam.kyushu-u.ac.jp [Research Institute for Applied Mechanics, Kyushu University, 6-1, Kasuga-Koen, Kasuga, Fukuoka 812-8580 (Japan); Zushi, H.; Yoshida, N. [Research Institute for Applied Mechanics, Kyushu University, 6-1, Kasuga-Koen, Kasuga, Fukuoka 812-8580 (Japan); Yugami, N.; Honda, T. [Interdisciplinary Graduate School of Engineering Science, Kyushu University, 6-1, Kasuga-Koen, Kasuga, Fukuoka 816-8580 (Japan); Hasegawa, M. [Research Institute for Applied Mechanics, Kyushu University, 6-1, Kasuga-Koen, Kasuga, Fukuoka 812-8580 (Japan); Mishra, K. [Interdisciplinary Graduate School of Engineering Science, Kyushu University, 6-1, Kasuga-Koen, Kasuga, Fukuoka 816-8580 (Japan); Kuzmin, A.; Nakamura, K.; Fujisawa, A.; Idei, H.; Nagashima, Y.; Watanabe, O.; Onchi, T.; Watanabe, H.; Tokunaga, K.; Higashijima, A.; Kawasaki, S.; Nakashima, H. [Research Institute for Applied Mechanics, Kyushu University, 6-1, Kasuga-Koen, Kasuga, Fukuoka 812-8580 (Japan); Takase, Y. [Graduate School of Frontier Science, University of Tokyo (Japan); and others

    2015-08-15

    Global particle balance in non-inductive long-duration plasma on QUEST has been investigated. Approximately 70% of the fuel hydrogen (H) was retained in the wall and then was almost exhausted just after the discharge. The global recycling ratio (R{sub g}), defined as the ratio of the evacuated H{sub 2} flux to that injected, was found to gradually increase during discharges and subsequently rose rapidly. To study the growth of R{sub g}, the thermal desorption spectra after deuterium implantation in a specimen exposed to QUEST plasma was analyzed with a model which includes reflection, diffusion, solution, recombination, trapping, and plasma-induced desorption in the re-deposition layer. The model reconstructs the growth of R{sub g} during a long-duration plasma and indicates solution plays a dominant role in the growth.

  6. Opposing Creationism: Scientists Organize.

    Science.gov (United States)

    Saladin, Kenneth S.

    1982-01-01

    Describes the response of the scientific community to creationist activism. A symposium entitled "Science and Belief" was held at the annual meeting of the American Association for the Advancement of Science to debate creationism. A network was organized to facilitate communication and political efficiency among anticreationist citizen lobbies.…

  7. Architectural Creation of Light

    DEFF Research Database (Denmark)

    Bülow, Katja

    2015-01-01

    Bidraget "Architectural Creation of Light" indgår sammen med 108 andre bidrag i bogen "You Say Light, I Think Shadow". Bogens indhold undersøger: "Hvad er lys". I dette bidrag besvares spørgsmålet gennem iagttagelser af arkitektstuderendes undersøgelser af lyset i deres arbejdsmodeller i...

  8. Path dependence and creation

    DEFF Research Database (Denmark)

    Garud, Raghu; Karnøe, Peter

    the place of agency in these theories that take history so seriously. In the end, they are as interested in path creation and destruction as they are in path dependence. This book is compiled of both theoretical and empirical writing. It shows relatively well-known industries such as the automobile...

  9. Creationism in Europe

    DEFF Research Database (Denmark)

    For decades, the creationist movement was primarily situated in the United States. Then, in the 1970s, American creationists found their ideas welcomed abroad, first in Australia and New Zealand, then in Korea, India, South Africa, Brazil, and elsewhere—including Europe, where creationism plays a...

  10. Opposing Creationism: Scientists Organize.

    Science.gov (United States)

    Saladin, Kenneth S.

    1982-01-01

    Describes the response of the scientific community to creationist activism. A symposium entitled "Science and Belief" was held at the annual meeting of the American Association for the Advancement of Science to debate creationism. A network was organized to facilitate communication and political efficiency among anticreationist citizen…

  11. Creationism in Europe

    DEFF Research Database (Denmark)

    Hjermitslev, Hans Henrik; Kjærgaard, Peter C.; Blancke, Stefaan;

    2013-01-01

    The purpose of our article is threefold. First, we present and discuss the extant literature on creationism in Europe (the “facts”). Within this section, we offer a review of the literature as well as an overview of the most remarkable developments and events recorded therein. Second, we indicate...

  12. Opposing Creationism: Scientists Organize.

    Science.gov (United States)

    Saladin, Kenneth S.

    1982-01-01

    Describes the response of the scientific community to creationist activism. A symposium entitled "Science and Belief" was held at the annual meeting of the American Association for the Advancement of Science to debate creationism. A network was organized to facilitate communication and political efficiency among anticreationist citizen…

  13. Architectural Creation of Light

    DEFF Research Database (Denmark)

    Bülow, Katja

    2015-01-01

    Bidraget "Architectural Creation of Light" indgår sammen med 108 andre bidrag i bogen "You Say Light, I Think Shadow". Bogens indhold undersøger: "Hvad er lys". I dette bidrag besvares spørgsmålet gennem iagttagelser af arkitektstuderendes undersøgelser af lyset i deres arbejdsmodeller i...

  14. Analysis of Volatile Components of Fresh and Cooked Frankincense by Thermal Desorption and GC/MS%热脱附-气相色谱/质谱联用法分析生、炙乳香挥发性成分

    Institute of Scientific and Technical Information of China (English)

    吴岳华; 周围; 张雅珩; 魏荣霞

    2013-01-01

    为了研究天然乳香的挥发性成分及生、炙乳香挥发性成分的异同,为乳香挥发油的工艺优化和品质评估提供科学的依据,同时为固体挥发性成分分析提供新思路,采用热脱附-气相色谱/质谱联用技术直接对自然状态下乳香颗粒的挥发性成分进行分析.结合NIST 08标准谱库检索和Mass WorksTM质谱解析软件的分析结果,在分离出的40余种挥发性成分中,最终确定出20种化学成分.结果表明:生、炙乳香中的挥发性成分主要由单萜、醇及酯类物质构成,其中以醋酸辛酯含量最高,约占挥发性成分的50%;其次为1-辛醇、芳樟醇、乙酸龙脑酯,在生乳香中的含量分别为19.44%、2.27%、2.64%,在炙乳香中的含量分别为9.12%、2.61%、1.33%.%In order to make clear the natural volatile composition of frankincense and the differences between fresh frankincense and cooked frankincense, to provide a scientific basis on improving techniques and evaluating qualities of frankincense volatile oil, and to offer a new method to analyse volatile composition from solid for reference, the volatile components of natural fresh and cooked frankincense were extracted and determined directly by thermal desorption and gas chromatography-mass spectrornetry(GC/MS). More than 40 components are separated and 20 components are identified by comparing their mass spectra with those contained in the NIST mass spectral database and Mass Works?software. The results show that the main components includ terpenes, alcohol and esters et al,n-octyl acetate is the most important volatile components to frankincense. The normalized peak areas exceed 50% both in fresh frankincense and cooked frankincense,followed by 1-octanol, lina-lool and bornyl acetate, the normalized peak areas in fresh frankincense are 19. 44%, 2. 27% and 2. 64%, in cooked frankincense are 9. 12%, 2. 61% and 1. 33%, respectively.

  15. Perspective Method of Betavoltaic Converter Creation

    Directory of Open Access Journals (Sweden)

    K.V. Rudenko

    2016-06-01

    Full Text Available Some results on planar diode structure creation by the method of a plasma-immersion ion implantation is presented in this paper. Obtained leakage current ~ 1 uA/cm2 at reverse voltage – 1 V. The cryogenic plasmochemical silicon etching process is developed, able to form the structured silicon layer with system of deep holes with high aspect ratio.

  16. Desorption of isopropyl alcohol from adsorbent with non-thermal plasma.

    Science.gov (United States)

    Shiau, Chen Han; Pan, Kuan Lun; Yu, Sheng Jen; Yan, Shaw Yi; Chang, Moo Been

    2016-11-24

    Effective desorption of isopropyl alcohol (IPA) from adsorbents with non-thermal plasma is developed. In this system, IPA is effectively adsorbed with activated carbon while dielectric barrier discharge is applied to replace the conventional thermal desorption process to achieve good desorption efficiency, making the treatment equipment smaller in size. Various adsorbents including molecular sieves and activated carbon are evaluated for IPA adsorption capacity. The results indicate that BAC has the highest IPA adsorption capacity (280.31 mg IPA/g) under the operating conditions of room temperature, IPA of 400 ppm, and residence time of 0.283 s among 5 adsorbents tested. For the plasma desorption process, the IPA selectivity of 89% is achieved with BAC as N2 is used as desorbing gas. In addition, as air or O2 is used as desorbing gas, the IPA desorption concentration is reduced, because air and O2 plasmas generate active species to oxidize IPA to form acetone, CO2, and even CO. Furthermore, the results of the durability test indicate that the amount of IPA desorbed increases with increasing desorption times and plasma desorption process has a higher energy efficiency if compared with thermal desorption. Overall, this study indicates that non-thermal plasma is a viable process for removing VOCs to regenerate adsorbent.

  17. Creation of Auditing Knowledge:

    DEFF Research Database (Denmark)

    Liempd, Dennis van

      Even though auditing research could play a role in understanding the many challenges that are threatening the profession, and in providing possible solutions, it seems to have failed in adequately doing so. This is for a major part because of a lack of research into auditing's basic assumptions......, and a too one-sided view on the creation of auditing knowledge. The purpose of this paper is to call for more (diverse) research in this area. Earlier calls have been few and far between, and have not resulted in a lot of research. Within the last two decades though, the auditing universe has changed so...... much that high-quality auditing research never has been needed more. By reviewing available literature challenges to the auditing profession are explored, and the creation of knowledge in general and auditing knowledge in particular are discussed with respect to methodological approaches and operative...

  18. Creationism and intelligent design.

    Science.gov (United States)

    Pennock, Robert T

    2003-01-01

    Creationism, the rejection of evolution in favor of supernatural design, comes in many varieties besides the common young-earth Genesis version. Creationist attacks on science education have been evolving in the last few years through the alliance of different varieties. Instead of calls to teach "creation science," one now finds lobbying for "intelligent design" (ID). Guided by the Discovery Institute's "Wedge strategy," the ID movement aims to overturn evolution and what it sees as a pernicious materialist worldview and to renew a theistic foundation to Western culture, in which human beings are recognized as being created in the image of God. Common ID arguments involving scientific naturalism, "irreducible complexity," "complex specified information," and "icons of evolution," have been thoroughly examined and refuted. Nevertheless, from Kansas to Ohio to the U.S. Congress, ID continues lobbying to teach the controversy, and scientists need to be ready to defend good evolution education.

  19. Deuterium retention after deuterium plasma implantation in tungsten pre-damaged by fast C+ ions

    Science.gov (United States)

    Efimov, V. S.; Gasparyan, Yu M.; Pisarev, A. A.; Khripunov, B. I.; Koidan, V. S.; Ryazanov, A. I.; Semenov, E. V.

    2016-09-01

    Thermal desorption of deuterium from W was investigated. Virgin samples and samples damaged by 10 MeV C 3+ ions were implanted from plasma in the LENTA facility at 370 K and 773 K. In comparison with the undamaged sample, deuterium retention in the damaged sample slightly increased in the case of deuterium implantation at RT, but decreased in the case of deuterium implantation at 773 K. At 773 K, deuterium was concluded to diffuse far behind the D ion range in the virgin sample, while C implantation region was concluded to be a barrier for D diffusion in the damaged sample.

  20. Creation, Identity and Reflection

    Directory of Open Access Journals (Sweden)

    Alina Beatrice Cheşcă

    2015-05-01

    Full Text Available The paper “Creation, Identity and Reflection” approaches the identification in the “mirror” of reality with creation, in other words seeking the authors’ identity in the reflected images. Reflection means attempting to find oneself, the mirror being the main principle of creation. Many characters become interesting only when they step into the world beyond the mirror, when their faces are doubled by the other self or when their selves are returned by other characters. The narcissistic concept of the mirror, i.e. the reflection in the mirror and the representation of the mirror itself, is a recurrent one in literature, but the reflection of the self which is not the self (as it is a reflection does not necessarily appear in a mirror or in a photograph or portrait. Sometimes, the not-self is returned to the self by another person or character. As far as Oscar Wilde’s theories are concerned, the main idea is that people are interesting for their masks, not for their inner nature. What Wilde calls “inner nature” is the characters’ un-reflected self and the mask is the reflection, the self in the mirror. Some characters’ relationships develop within a fiction that they dramatically try to preserve and protect with the risk of suffering. They refuse to take off the masks which define them in the others’ minds and hearts; the narcissistic individuals (both artists and characters seek and love their own image which they project upon facts, thus creating a fictive realm.

  1. Autopoiesis as Self-Creation and the Source of Creation

    Directory of Open Access Journals (Sweden)

    Saulius Kanišauskas

    2011-04-01

    Full Text Available The article focuses on the phenomenon of creation from Varela's autopoiesis theory point of view in the context of cognitive sciences and synergetics. Creation is defined as emergence and finding of new qualities; four levels of it are distinguished: absolute, essential, normal and adaptive. It is revealed that Varela's autopoiesis is a process of creation in which autopoiesis intertwines with praxis, i.e. spontaneous and emergent development of something new is inseparable from materializing activity. The conception of endogenic source creation is analyzed taking into consideration deep philosophical insights of autopoiesis theory and positions of cognitive science alongside with downward causation conception. An attempt is made to show that the conception of endogenic source is in principle compatible with the conception of exogenic source creation (they complement each other. It should be noted that poiesis (creation is related to the determined chaos in the human brain which forms during sleep. 

  2. 气相色谱与热解吸联用技术在室内环境检测领域的应用及进展%Application and Development of Gas Chromatography Hyphenated with Thermal Desorption in the Field of Indoor Environment Testing

    Institute of Scientific and Technical Information of China (English)

    贾祥焱

    2012-01-01

    It is a brief introduction of gas chromatography and the application and development of gas chromatography hyphenated with thermal desorption in the test benzene and TVOC of indoor environment testing,and puts forward outlook and prospect in it.It provides favorable value in the development of gas chromatographic technique in indoor environment testing.%简要介绍了气相色谱法,及其与热解吸联用在民用建筑工程室内环境检测中检测苯、TVOC的应用和进展。并提出了气相色谱与热解吸联用技术的前景与展望,为气相色谱技术在室内环境检测领域的发展提供有利价值。

  3. ENRICHMENT OF TRACE AMOUNTS OF PESTICIDES IN POLLUTED WATER BY A NOVEL TYPE OF SOLID PHASE EXTRACTION ELEMENT FOR THEIR THERMAL DESORPTION GC/MS ANALYSIS%新型固相萃取器用于污染水样中痕量杀虫剂的浓缩及热解吸气相色谱-质谱分析

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A novel type of solid-phase extraction element named"Magic Chemisorber" is developed for sorptive enrichment of dilute analytes from aqueous samples with high extraction efficiencies due to its capacious layer of sorbent polydimethylsiloxane.This extraction element combined with thermal desorption-gas chromatography/mass spectrometry using a pyrolysis-GC/MS system was applied to extract the pesticides from water samples over a concentration range of 10-3 to 103 μg*l-1.The method showed good li-nearity for the tested concentration range with regression coefficients of 0.995 for over 5 decades.Limits of detection at a sub-ng*l-1(ppt)level were achieved and the reproducibility of the measurements was found to be fairly good,with relative standard deviation below 8%.

  4. Aesthetics and collective creation

    DEFF Research Database (Denmark)

    Jakobsen, Annette Svaneklink

    2013-01-01

    Tokyo, Nicolas Bourriaud (Bourriaud:1998) and now, the art centre stands as place where a cultural institution, an architectural mode of thinking and participatory artistic experiments work together. Recently, is has become of increasing interest to art museums to be relational and socially aware...... possibilities for relations and differentiated movement patterns to further transform the potentials of visitorʼs interactions with each other and with works of art. Lacaton & Vassalʼs relational, bottom-up architecture resonated well with the aesthetic thinking by one of the initial directors of the Palais de...... that reactualises the experimental exhibition space designed by Lina Bo Bardi for Museu de Arte de Sao Paulo (1968). These aspects of the practice of museums and art centres, where social change, creation and exhibition experience affect each other raise the question of how (social) change is related to aesthetics...

  5. Life after stoma creation

    DEFF Research Database (Denmark)

    Danielsen, Anne Kjærgaard

    2013-01-01

    , as well as an alteration in the bodily design. Research in the field may provide additional information about central elements when adapting to life with a stoma. There are currently no studies that adequately focus on the relationship between health-related quality of life and stoma construction...... in a Danish context, neither for temporary or permanent construction, nor in relation to the importance of stoma handling. Purpose: The overall objective of the study was to investigate health-related quality of life related to stoma creation and patient education. Methodologically, the project......: Impact on everyday life and Educational Needs. The study included 15 participants who were interviewed in groups related to whether they were treated for cancer or non-cancer. The results showed that participants often experienced the stoma as a taboo, and emotions related to stigma were identified...

  6. Ludic Educational Game Creation Tool

    DEFF Research Database (Denmark)

    Vidakis, Nikolaos; Syntychakis, Efthimios; Kalafatis, Konstantinos

    2015-01-01

    creation tool features a web editor, where the game narrative can be manipulated, according to specific needs. Moreover, this tool is applied for creating an educational game according to a reference scenario namely teaching schoolers road safety. A ludic approach is used both in game creation and play...

  7. The Co-creation Continuum

    DEFF Research Database (Denmark)

    Ind, Nicholas; Iglesias, Oriol; Markovic, Stefan

    2017-01-01

    Co-creation can open up a brand to the outside world and help it to generate relevant innovations. However, there is scarce empirical evidence as to how managers actually use co-creation to connect with customers and other stakeholders and build enduring innovation-oriented relationships with the...

  8. Value Creation in International Business

    DEFF Research Database (Denmark)

    Vedel, Mette; Servais, Per

    2017-01-01

    The edited collection brings into focus the meanings, interpretations and the process of value creation in international business. Exploring value creation in the context of emerging and developed economies, Volume 2 takes the perspective of small and medium sized enterprises and examines various...... approaches to value creation in the process of firm internationalization. Providing theoretical and practical insights, the authors open an intellectual debate into what value is, and how it is created through the internationalization activities of firms. Value Creation in International Business...... is a pioneering two volume work intended to provoke theoretical and empirical development in International Business research. Moreover, it is intended as a bridge between concepts derived from general business firm-level research agendas such as value creation and business model, and internationalization...

  9. Job Creation and Job Types

    DEFF Research Database (Denmark)

    Kuhn, Johan Moritz; Malchow-Møller, Nikolaj; Sørensen, Anders

    2016-01-01

    We extend earlier analyses of the job creation of start-ups versus established firms by considering the educational content of the jobs created and destroyed. We define education-specific measures of job creation and job destruction at the firm level, and we use these measures to construct...... a measure of “surplus job creation”, defined as jobs created on top of any simultaneous destruction of similar jobs in incumbent firms in the same region and industry. Using Danish employer-employee data from 2002–2007 that identify the start-ups and that cover almost the entire private sector......, these measures allow us to provide a more nuanced assessment of the role of entrepreneurial firms in the job-creation process than in previous studies. Our findings show that although start-ups are responsible for the entire overall net job creation, incumbents account for more than one-third of net job creation...

  10. Job Creation and Job Types

    DEFF Research Database (Denmark)

    Kuhn, Johan M.; Malchow-Møller, Nikolaj; Sørensen, Anders

    We extend earlier analyses of the job creation of start-ups vs. established firms by taking into consideration the educational content of the jobs created and destroyed. We define educationspecific measures of job creation and job destruction at the firm level, and we use these to construct...... a measure of “surplus job creation” defined as jobs created on top of any simultaneous destruction of similar jobs in incumbent firms in the same region and industry. Using Danish employer-employee data from 2002-7, which identify the start-ups and which cover almost the entire private sector......, these measures allow us to provide a more nuanced assessment of the role of entrepreneurial firms in the job-creation process than previous studies. Our findings show that while start-ups are responsible for the entire overall net job creation, incumbents account for more than a third of net job creation within...

  11. Knowledge Sharing is Knowledge Creation

    DEFF Research Database (Denmark)

    Greve, Linda

    2015-01-01

    communication and knowledge creation to an intervention study in a large Danish food production company. For some time a specific group of employees uttered a wish for knowledge sharing, but it never really happened. The group was observed and submitted to metaphor analysis as well as analysis of co......-creation strategies. Confronted with the results, the group completely altered their approach to knowledge sharing and let it become knowledge co-creation. The conclusions are, that knowledge is and can only be a diverse and differentiated concept, and that groups are able to embrace this complexity. Thus rather than...

  12. Job Creation and Job Types

    DEFF Research Database (Denmark)

    Kuhn, Johan M.; Malchow-Møller, Nikolaj; Sørensen, Anders

    , these measures allow us to provide a more nuanced assessment of the role of entrepreneurial firms in the job-creation process than previous studies. Our findings show that while start-ups are responsible for the entire overall net job creation, incumbents account for more than a third of net job creation within...... high-skilled jobs. Moreover, start-ups “only” create around half of the surplus jobs, and even less of the high-skilled surplus jobs. Finally, our approach allows us to characterize and identify differences across industries, educational groups and regions....

  13. 氯苯类易挥发有机污染土壤异位低温热脱附实例研究%Case Study On Ex-situ Remediation of Chlorobenzene-Like Volatile Organic Compounds (VOCs) Contaminated Soil With Technique of Low-Temperature Thermal Desorption

    Institute of Scientific and Technical Information of China (English)

    王湘徽; 祝欣; 龙涛; 邓绍坡; 林玉锁; 胡韬

    2016-01-01

    The technique of low⁃temperature thermal desorption was used to remedy chlorobenzene⁃like VOCs contaminated soil. Results show that VOCs were effectively removed after the treatment, with removal rate reaching 85% or more for all the tested VOCs. In field trials, a specialized soil remediation machine KH200 was used to crush the soil and have it mixed with lime in full⁃closed operation to avoid dust pollution. Through raising soil temperature and lowering soil water content, desorption and volatilization of VOC was effectively accelerated. All the findings in the experiment demon⁃strate that the use of the technique of low⁃temperature thermal desorption and the KH200 equipment is a promising ap⁃proach to efficient and low cost remediation of contaminated soils in sites of deserted chemical plants.%针对南京市某大型化工企业退役场地,结合场地修复目标,使用生石灰对场地氯苯类挥发性有机污染物( VOCs)污染土壤进行异位低温热脱附处理。实验室试验结果表明,该方法可有效去除土壤中的VOCs,处理后各污染物去除率均达85%以上。在现场试验中,采用专业土壤修复设备KH200进行土壤破碎和药剂混合,处理过程全封闭运行,可有效降低扬尘等问题。通过投加生石灰提高土壤温度、降低土壤含水量的方法,有效地促进了土壤中VOCs的解吸和挥发,是一种高效率、低成本的土壤修复技术,经过KH200修复设备处理后土壤中各污染物均达到场地修复目标,具备工程应用可行性。

  14. Experimental studies on removal of airborne haloanisoles by non-thermal plasma air purifiers

    DEFF Research Database (Denmark)

    Fang, Lei; Hallam, David; Bermúdez, Raúl

    2016-01-01

    A laboratory study was conducted to test the performance of non-thermal plasma air purifiers on its removal effectiveness of two haloanisoles – 2,4,6-trichloroanisole (TCA) and 2,4,6-Tribromoanisole (TBA). TCA and TBA are the two major compounds found in wine cellars that can contaminate wine...... to produce unpalatable mouldy and musty tastes. The test was first conducted in a climate chamber. The plasma air purifier was installed in a test rig developed for the testing and challenged by airflow with certain concentrations of TCA and TBA. Air samples upstream and downstream of the air purifier...... was collected by Tenax tubes and the concentration of TCA and TBA were analyzed by thermal desorption GC–MS. The results showed that the plasma air purifier was effective on removing TCA and TBA with a single pass efficiency of better than 82%. The effect was further validated in a wine cellar under a realistic...

  15. Nonlinear phenomenon in nanostructures creation by fast cluster ions

    Science.gov (United States)

    Moslem, W. M.; El-Said, A. S.; Sabry, R.; Shalouf, A.; El-Labany, S. K.; Bahlouli, H.

    2017-01-01

    The development of accelerators technology offers a new window for the creation of surface nanostructures in an efficient and accurate way. The use of 30 MeV C60 cluster ions enables the creation of nano-hillocks of size larger than the ones produced by GeV monoatomic ions. The physical mechanism underlying the realization of such nanostructures is elucidated using a plasma expansion approach. Numerical analysis showed that increasing the ionic temperature (number density) ratios would lead to decrease (increase) the nano-hillocks height.

  16. Studies of lithium deposition and D retention on tungsten samples exposed to Li-seeded plasmas in PISCES-A

    Science.gov (United States)

    Tabarés, F. L.; Alegre, D.; Baldwin, M.; Nishijima, D.; Simmonds, M.; Doerner, R.; Alves, E.; Mateus, R.

    2017-04-01

    The interaction between lithium-seeded deuterium plasmas and tungsten targets has been studied in the PISCES-A divertor plasma simulator. Tungsten samples, of ITER-grade, with a diameter of 25 and 2 mm thick, were held at temperatures ranging from 403 to 873 K and exposed to Li/D plasmas under different plasma conditions and fixed total fluences of 5 ×1025 m‑2, with typical particle flux values of (1–5) × 1022 m‑2 s‑1. The deuterium and lithium contents of the samples after irradiation were analyzed by thermal desorption spectroscopy and nuclear reaction analysis (NRA). No lithium deposition was found within the sensitivity range of NRA, except for the cold (403 K) sample on which a layer with Li atomic density below 2 × 1022 m‑2 was detected. Deuterium retention values in the range of 1018 m‑2 were measured, even for the Li deposition conditions.

  17. Modeling Repulsive Gravity with Creation

    Indian Academy of Sciences (India)

    R. G. Vishwakarma; J. V. Narlikar

    2007-03-01

    There is a growing interest among cosmologists for theories with negative energy scalar fields and creation, in order to model a repulsive gravity. The classical steady state cosmology proposed by Bondi, Gold & Hoyle in 1948, was the first such theory which used a negative kinetic energy creation field to invoke creation of matter. We emphasize that creation plays a very crucial role in cosmology and provides a natural explanation to the various explosive phenomena occurring in local ( < 0.1) and extra galactic universe.We exemplify this point of view by considering the resurrected version of this theory – the quasi-steady state theory, which tries to relate creation events directly to the large scale dynamics of the universe and supplies more natural explanations of the observed phenomena. Although the theory predicts a decelerating universe at the present era, it explains successfully the recent SNe Ia observations (which require an accelerating universe in the standard cosmology), as we show in this paper by performing a Bayesian analysis of the data.

  18. Color, light, and altruistic creation

    Science.gov (United States)

    Charnay, Yves

    2002-06-01

    It seems necessary to me to combine a certain technical inventivity with plastic creation, a particular poetry arises from this relation. The sources of inspiration for works, especially works in which color plays a pre-eminent role, do not only come from nature. The fantasy of the creators evolves and changes thanks to discoveries and technological inventions. My work as a painter has made me particularly sensitive to the diversity of the plastic writings in general and to the chromatic writings in particular. (1) Environmental creation imposes a renewal of the means of creation. Conducting experimental works, I study the particularities of light, mainly its incidence on materials (transmission, reflection, colors, textures, etc.) and its mobility. These works are a source of inspiration for my architectural works and nurture my lectures at the Ecole Nationale Superieure des Arts Decoratifs (National College of Decorative Arts). Environmental creation also imposes some qualities on the artist since he, whether he serves a social entity or a person, serves the whole collectivity. Environmental creation has to be envisaged as an altruistic approach.

  19. Components of Co-creation

    DEFF Research Database (Denmark)

    Tanev, Stoyan

    2009-01-01

    , such an approach misses the advantages of an empirically driven quantitative approach that benefits from larger size samples and is more appropriate for theory building through the development and testing of hypotheses. It is important, therefore, to seek the development of a research methodology that combines...... the benefits of both qualitative and quantitative research approaches for studying the nature of value co-creation. The article provides a first attempt to identify the main research steps of such a methodology. It provides some preliminary results on the key components of value co-creation between firms...... of both qualitative and quantitative techniques. One of the main contributions of this article is to suggest and explore the possibility for using the QCA technique in future research on value co-creation....

  20. Movement in aesthetic form creation

    DEFF Research Database (Denmark)

    Thomsen, Bente Dahl

    2015-01-01

    This paper presents the good practice based experiences found when movement is used to strengthen form creation and to create flow in the process of artistic education. Faced with the design engineering students’ problems with creating forms with aesthetic statements, the experiences with movement...... inspired the thesis that the design engineers’ training in aesthetic form creation can be improved by integrating the movement potential into their education. The paper documents the on-going work on developing a model for embodied creation of form called ‘Somatechne model’. The study also identifies...... a lens to assess the students’ development of mind-body skills, known as ‘The Three Soma’. The Somatechne model also helps to identify the activity that gives the students the opportunity to develop their sensibility and thus aesthetic attention....

  1. Evolutionary Creation: Moving beyond the Evolution versus Creation Debate

    Science.gov (United States)

    Lamoureux, Denis O.

    2010-01-01

    Evolutionary creation offers a conservative Christian approach to evolution. It explores biblical faith and evolutionary science through a Two Divine Books model and proposes a complementary relationship between Scripture and science. The Book of God's Words discloses the spiritual character of the world, while the Book of God's Works reveals the…

  2. Co-Creation in Distributed Value Creation Systems and Networks

    DEFF Research Database (Denmark)

    Bang, Anne Louise; Christensen, Poul Rind

    organizational systems with activities crossing organizational boundaries. Based on this assumption, it is proposed that designing includes stakeholders in a number of organizational units, cooperating in order to contribute to the process of creation and implementation of specific designs. It is thus proposed...

  3. Entrepreneuring as Organisation-Creation

    DEFF Research Database (Denmark)

    Hjorth, Daniel

    2014-01-01

    This chapter aims at making a contribution to the study of entrepreneurship and creativity by developing a processual conceptualisation of a form of entrepreneurial creativity called entrepreneuring or organisation-creation. Such a processual conceptualisation of entrepreneuring will answer...... the long-standing call in entrepreneurship research for an enhanced capacity to study organisation-in-creation. I believe recent advances in process thinking, in organisation studies have provided us, finally, with such 'changes in our perceptions and methodologies', meaning we have now a capacity to step...

  4. Value Co-creation Behaviour

    DEFF Research Database (Denmark)

    Laud, Gaurangi; Karpen, Ingo Oswald

    2017-01-01

    Purpose: The purpose of this paper is to identify antecedents and consequences ofcustomers’ value co-creation behaviour (VCB). VCB as a means to facilitatevalue realisation processes is gaining importance in service research andpractice. Encouraging such enactments can be challenging, but can also...... offercompetitive advantages. Design/methodology/approach: We empirically investigate a conceptual model by converging threecontemporary concepts of co-creation research – embeddedness, VCB and value-in-context– and examining the interdependencies between them. Data were collected in anonline forum of a leading...

  5. Surface morphology and deuterium retention in tungsten exposed to high flux D plasma at high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Y.Z. [Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); De Temmerman, G. [FOM Institute DIFFER-Dutch Institute for Fundamental Energy Research, Edisonbaan 14, 3439 MN Nieuwegein (Netherlands); ITER Organization, Route de Vinon-sur-Verdon-CS90046, 13067 St Paul Lez Durance Cedex (France); Luo, G.-N. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Xu, H.Y. [Science and Technology on Surface Physics and Chemistry Laboratory, Mianyang, Sichuan 621907 (China); Li, C.; Fu, B.Q. [Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Liu, W., E-mail: liuw@mail.tsinghua.edu.cn [Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2015-02-15

    Surface modifications and deuterium retention induced in tungsten by high fluxes (10{sup 24} m{sup −2} s{sup −1}) low energy (38 eV) deuterium ions were studied as a function of surface temperature. Blister formation was studied by scanning electron microscopy and electron backscatter diffraction, while deuterium retention was measured by thermal desorption spectroscopy. Blisters are observed on the surface exposed at different temperatures, ranging from 493 K to 1273 K. The blister density and D retention decrease with the increasing exposure temperature. The formation of blisters at high temperatures is attributed to the high flux of D plasma. At 943 K, with the increasing fluence, there is trend to the saturation of D retention and blister density. The defects caused by plasma exposure have an important effect on the D trapping and blistering behavior. The formation of blisters has a strong relationship with slipping system of tungsten.

  6. Tungsten nitride coatings obtained by HiPIMS as plasma facing materials for fusion applications

    Science.gov (United States)

    Tiron, Vasile; Velicu, Ioana-Laura; Porosnicu, Corneliu; Burducea, Ion; Dinca, Paul; Malinský, Petr

    2017-09-01

    In this work, tungsten nitride coatings with nitrogen content in the range of 19-50 at% were prepared by reactive multi-pulse high power impulse magnetron sputtering as a function of the argon and nitrogen mixture and further exposed to a deuterium plasma jet. The elemental composition, morphological properties and physical structure of the samples were investigated by Rutherford backscattering spectrometry, atomic force microscopy and X-ray diffraction. Deuterium implantation was performed using a deuterium plasma jet and its retention in nitrogen containing tungsten films was investigated using thermal desorption spectrometry. Deuterium retention and release behaviour strongly depend on the nitrogen content in the coatings and the films microstructure. All nitride coatings have a polycrystalline structure and retain a lower deuterium level than the pure tungsten sample. Nitrogen content in the films acts as a diffusion barrier for deuterium and leads to a higher desorption temperature, therefore to a higher binding energy.

  7. Components of Co-creation

    DEFF Research Database (Denmark)

    Allen, Stephen; Bailetti, Tony; Tanev, Stoyan

    2013-01-01

    There is a growing body of literature dedicated to the discussion of value co -creation frameworks, mechanisms and processes. However , these typically focus on the study, discussion and analysis of a small number of cases using deep, ethnographic description of their practices aiming at conceptu...

  8. Electron pair creation by photons

    NARCIS (Netherlands)

    Holtwijk, Theodoor

    1960-01-01

    In our experiment on the creation of electron pairs a 5 MeV betatron was used as radiation source and a cloud chamber (with magnetic field) was used as detection instrument. The experimental arrangement is described in section 2.1. The cloud chamber was of the overcompression type so that the recove

  9. Knowledge Creation in Constructivist Learning

    Science.gov (United States)

    Jaleel, Sajna; Verghis, Alie Molly

    2015-01-01

    In today's competitive global economy characterized by knowledge acquisition, the concept of knowledge management has become increasingly prevalent in academic and business practices. Knowledge creation is an important factor and remains a source of competitive advantage over knowledge management. Constructivism holds that learners learn actively…

  10. Uprising of Creation in Education

    Science.gov (United States)

    Hatamleh, Habes Mohamed

    2015-01-01

    This research (Uprising of Creation in Education) aims at defining the importance of creativity in education, and its reflection on the elements of the educational process. Creativity is regarded an important element in the nations progress, which depends on the minds of their sons. Creativity became the language of the present age, after the…

  11. Juvenile Courts. Creation and development

    Directory of Open Access Journals (Sweden)

    Montserrat GONZÁLEZ FERNÁNDEZ

    2013-11-01

    Full Text Available This paper studies the creation of Juvenile or Children's Courts in Spain, analysing their reasons and aims, as well as the ethical and political connotations present on their way of acting. Their history and the one of the institutions that complement them is built from the legislation, writings and ideas of their promoters.

  12. Electron pair creation by photons

    NARCIS (Netherlands)

    Holtwijk, Theodoor

    1960-01-01

    In our experiment on the creation of electron pairs a 5 MeV betatron was used as radiation source and a cloud chamber (with magnetic field) was used as detection instrument. The experimental arrangement is described in section 2.1. The cloud chamber was of the overcompression type so that the recove

  13. Ecological ethics and creation faith

    Directory of Open Access Journals (Sweden)

    Ulrich Körtner

    2016-05-01

    Full Text Available Over past decades a concept of ecological ethics has taken root, which is often equated with environmental ethics. Church and theology have also responded to the environmental crisis. In the last third of the past century an intense discourse about the concerns and extent of a so called creation ethics was conducted. In connection with the question of a creation ethics, and the global responsibility of humans for the biosphere of our planet, the topic of creation has also gained new attention in dogmatics. In this way, ecology has also become a topic of systematic theology. The article focuses on the debate in the German speaking context. Occasionally, a quasi-religious elevation of ecology to the status of a doctrine of salvation is observable. Because theology always also has a function of critique of religion, it must also critically engage the sometimes open and sometimes hidden religious contents and claims of eco-ethical concepts. For this purpose, the first step of the present contribution is to more precisely determine the concepts of creation and nature. Thereafter, the problem of anthropocentrism is analysed. In a further step, the concept of sustainability is analysed. In conclusion, the main features of a responsibility-ethics model of ecological ethics are outlined.

  14. Knowledge Work and Knowledge Creation

    DEFF Research Database (Denmark)

    Dau, Susanne

    2016-01-01

    The purpose of this paper is to address how instruction influences the creative knowledge work. Based on different perspectives on instructions and the actions followed, this paper reveal how educators, having different competencies of ICT-instructions, influence students’ creative knowledge work......, and students’ knowledge creation....

  15. Thermal Desorption-Gas Chromatography or Gas Chromatograph-Mass Spectrometry for Analysis of Semi-Volatile Compounds on Atmospheric Particulate Matters%热解析-气相色谱或气相色谱-质谱法分析大气可吸入颗粒物中的半挥发性有机化合物

    Institute of Scientific and Technical Information of China (English)

    孟虎; 赵景红; 段春凤; 郝亮; 关亚风

    2014-01-01

    A thermal desorption ( TD) device was developed and coupled to gas chromatography ( GC) or gas chromatography-mass spectrometry ( GC-MS ) for the qualitative and quantitative analysis of semi-volatile organic compounds on atmospheric particulate matters ( PM ) . The TD was operated by direct heating and placed on the GC injector, leading to high heating rate and easy transfer of analytes to GC without focusing of analytes by cold trap. For establishing the TD-GC method, the materials used for supporting PM samples, temperature and time of thermal desorption, and types of sample injection were investigated for detection of sixteen polycyclic aromatic hydrocarbons ( PAHs) and nine n-alkanes. The limits of detection of the proposed TD-GC method were in the range of 0. 014-0. 093 ng for PAHs, and 0. 016-0. 026 ng for n-alkanes, respectively, with the correlation coefficients of correlation above 0. 9975. The TD-GC method was applied to the determination of trace PAHs and n-alkanes on PM10 samples from three cities. The recoveries were in the range of 95%-135% ( PAHs) and 95%-115% ( n-alkanes) , respectively. Finally, the TD was coupled to GC-MS for comparison of the contents of PAHs and n-alkanes on PMx with different particulate size ( x=10 , 5, 2, 1, 0. 5, 0. 25, 0. 1).%研制了一种热解析装置,并与气相色谱或气相色谱-质谱联用,定性定量分析了大气可吸入颗粒物中的半挥发性有机物。装置为直热式加热,升温速率快;直接安装在色谱进样器上方,无需冷阱聚焦。将热解析装置与气相色谱联用,优化了样品承载体材质、热解析条件和进样模式,并用于16种多环芳烃和9种正构烷烃的检测。结果表明,热解析-气相色谱方法对多环芳烃和正构烷烃的检出限分别为0.014~0.093 ng和0.016~0.026 ng,线性相关系数大于0.9975;用于3个城市PM10中的痕量多环芳烃和正构烷烃的定量测定,回收率分别在95%~135%(多环芳烃)和95%~115%(正构烷

  16. 搅拌棒萃取-热脱附/气质联用法测定水中2-MIB和土臭素%Determination of 2-Methylisoborneol and Geosmin in Water Using Stir Bar Sorptive Extraction-Thermal Desorption/Gas Chromatography Coupled with Mass Spectrometry

    Institute of Scientific and Technical Information of China (English)

    范苓; 张晓赟; 秦宏兵; 顾海东

    2013-01-01

    A method using stir bar sorptive extraction ( SBSE)-thermal desorption ( TD)/gas chromatogra-phy coupled with mass spectrometry ( GCMS) was developed to determinate ultra-trace level of 2-methylisoborneol (2-MIB) and geosmin in water .SBSE and TD parameters were optimized through blank spiked sample .The method showed good linearity ( r>0 .999 ) over concentration range from 1 ng/L to 200 ng/L and high sensitivity ( the MDL of 2-MIB and geosmin were 0 .31 ng/L and 0 .15 ng/L respectively ) .The spiked recovery of blank and real samples ranged from 82 .4%to 116%with RSD <10%.%采用搅拌棒萃取-热脱附/气质联用法测定水中2-甲基异莰醇和土臭素,优化了搅拌棒萃取和热脱附进样的条件。试验表明:两种目标化合物在1.00 ng/L~200 ng/L范围内线性良好,2-甲基异莰醇的相关系数为0.9993,土臭素的相关系数为0.9997,方法检出限分别为0.31 ng/L和0.15 ng/L;空白和实际样品的加标回收率为82.4%~116%,测定结果的RSD<10%。

  17. The investigation of structure, chemical composition, hydrogen isotope trapping and release processes in deposition layers on surfaces exposed to DIII-D divertor plasma

    Energy Technology Data Exchange (ETDEWEB)

    Buzhinskij, O.I.; Opimach, I.V.; Barsuk, V.A. [TRINITI, Troitsk (Russian Federation); Arkhipov, I.I. [Russian Academy of Science, Moscow (Russian Federation). Inst. of Physical Chemistry; West, W.P.; Wong, C.P.C. [General Atomics, San Diego, CA (United States); Whyte, D. [Univ. of California, San Diego, CA (United States); Wampler, W.R. [Sandia National Labs., Albuquerque, NM (United States)

    1998-05-01

    The exposure of ATG graphite sample to DIII-D divertor plasma was provided by the DiMES (Divertor Material Evaluation System) mechanism. The graphite sample arranged to receive the parallel heat flux on a small region of the surface was exposed to 600ms of outer strike point plasma. The sample was constructed to collect the eroded material directed downward into a trapping zone onto s Si disk collector. The average heat flux onto the graphite sample during the exposure was about 200W/cm{sup 2}, and the parallel heat flux was about 10 KW/cm{sup 2}. After the exposure the graphite sample and Si collector disk were analyzed using SEM, NRA, RBS, Auger spectroscopy. IR and Raman spectroscopy. The thermal desorption was studied also. The deposited coating on graphite sample is amorphous carbon layer. Just upstream of the high heat flux zone the redeposition layer has a globular structure. The deposition layer on Si disk is composed also from carbon but has a diamond-like structure. The areal density of C and D in the deposited layer on Si disk varied in poloidal and toroidal directions. The maximum D/C areal density ratio is about 0.23, maximum carbon density is about 3.8 {times} 10{sup 18}cm{sup {minus}2}, maximum D area density is about 3 {times} 10{sup 17}cm{sup 2}. The thermal desorption spectrum had a peak at 1,250K.

  18. Accelerating Value Creation with Accelerators

    DEFF Research Database (Denmark)

    Jonsson, Eythor Ivar

    2015-01-01

    Accelerators can help to accelerate value creation. Accelerators are short-term programs that have the objective of creating innovative and fast growing ventures. They have gained attraction as larger corporations like Microsoft, Barclays bank and Nordea bank have initiated and sponsored accelera......Accelerators can help to accelerate value creation. Accelerators are short-term programs that have the objective of creating innovative and fast growing ventures. They have gained attraction as larger corporations like Microsoft, Barclays bank and Nordea bank have initiated and sponsored...... an approach to facilitate implementation and realization of business ideas and is a lucrative approach to transform research into ventures and to revitalize regions and industries in transition. Investors have noticed that the accelerator approach is a way to increase the possibility of success by funnelling...

  19. Network testbed creation and validation

    Energy Technology Data Exchange (ETDEWEB)

    Thai, Tan Q.; Urias, Vincent; Van Leeuwen, Brian P.; Watts, Kristopher K.; Sweeney, Andrew John

    2017-03-21

    Embodiments of network testbed creation and validation processes are described herein. A "network testbed" is a replicated environment used to validate a target network or an aspect of its design. Embodiments describe a network testbed that comprises virtual testbed nodes executed via a plurality of physical infrastructure nodes. The virtual testbed nodes utilize these hardware resources as a network "fabric," thereby enabling rapid configuration and reconfiguration of the virtual testbed nodes without requiring reconfiguration of the physical infrastructure nodes. Thus, in contrast to prior art solutions which require a tester manually build an emulated environment of physically connected network devices, embodiments receive or derive a target network description and build out a replica of this description using virtual testbed nodes executed via the physical infrastructure nodes. This process allows for the creation of very large (e.g., tens of thousands of network elements) and/or very topologically complex test networks.

  20. Network testbed creation and validation

    Energy Technology Data Exchange (ETDEWEB)

    Thai, Tan Q.; Urias, Vincent; Van Leeuwen, Brian P.; Watts, Kristopher K.; Sweeney, Andrew John

    2017-04-18

    Embodiments of network testbed creation and validation processes are described herein. A "network testbed" is a replicated environment used to validate a target network or an aspect of its design. Embodiments describe a network testbed that comprises virtual testbed nodes executed via a plurality of physical infrastructure nodes. The virtual testbed nodes utilize these hardware resources as a network "fabric," thereby enabling rapid configuration and reconfiguration of the virtual testbed nodes without requiring reconfiguration of the physical infrastructure nodes. Thus, in contrast to prior art solutions which require a tester manually build an emulated environment of physically connected network devices, embodiments receive or derive a target network description and build out a replica of this description using virtual testbed nodes executed via the physical infrastructure nodes. This process allows for the creation of very large (e.g., tens of thousands of network elements) and/or very topologically complex test networks.

  1. Creationism, Evolution, and Science Education

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Eugenie C. (National Center for Science Education)

    2005-06-22

    Many topics in the curriculum of American schools are controversial, but perhaps the one with the longest tenure is evolution. Three arguments are made against evolution: that it is allegedly weak science ('evolution is a theory in crisis'); that it is incompatible with religion; and that it is only 'fair' to 'balance' evolution with creationism. Regardless of the appropriateness of their application to science education, all three of the arguments are made to try to restrict the teaching of evolution. Variants of the fairness argument such as balancing evolution with 'scientific alternatives to evolution' or balancing evolution with 'arguments against evolution' have in fact become the current predominant antievolutionist strategy. Current events in the creationism/evolution controversy will be reviewed, and suggestions made for how to promote sound science education in the schools.

  2. Serum/plasma methylmercury determination by isotope dilution gas chromatography-inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Baxter, Douglas C; Faarinen, Mikko; Österlund, Heléne; Rodushkin, Ilia; Christensen, Morten

    2011-09-01

    A method for the determination of methylmercury in plasma and serum samples was developed. The method uses isotope dilution with (198)Hg-labeled methylmercury, extraction into dichloromethane, back-extraction into water, aqueous-phase ethylation, purge and trap collection, thermal desorption, separation by gas chromatography, and mercury isotope specific detection by inductively coupled plasma mass spectrometry. By spiking 2 mL sample with 1.2 ng tracer, measurements in a concentration interval of (0.007-2.9) μg L(-1) could be performed with uncertainty amplification factors levels of 0.14 μg L(-1), 0.35 μg L(-1) and 2.8 μg L(-1), with recoveries in the range 82-110%. Application of the method to 50 plasma/serum samples yielded a median (mean; range) concentration of methylmercury of 0.081 (0.091; methylmercury has been directly measured in this kind of specimen, and is therefore the first estimate of a reference range.

  3. Quantum Creation of BTZ Black Hole

    CERN Document Server

    Wu Zhong Chao

    1999-01-01

    The constrained Instanton method is used to study quantum creation of a BTZ black hole. It is found that the relative creation probability is the exponential of the negative sum of the entropy associated with the outer and inner black hole horizons. The quantum creation of the 4- or higher dimensional versions of the BTZ black hole are also studied.

  4. VAC*TRAX - thermal desorption for mixed wastes

    Energy Technology Data Exchange (ETDEWEB)

    McElwee, M.J.; Palmer, C.R. [RUST-Clemson Technical Center, Anderson, SC (United States)

    1995-10-01

    The patented VAC*TRAX process was designed in response to the need to remove organic constituents from mixed waste, waste that contains both a hazardous (RCRA or TSCA regulated) component and a radioactive component. Separation of the mixed waste into its hazardous and radioactive components allows for ultimate disposal of the material at existing, permitted facilities. The VAC*TRAX technology consists of a jacketed vacuum dryer followed by a condensing train. Solids are placed in the dryer and indirectly heated to temperatures as high as 2600{degrees}C, while a strong vacuum (down to 50 mm Hg absolute pressure) is applied to the system and the dryer is purged with a nitrogen carrier gas. The organic contaminants in the solids are thermally desorbed, swept up in the carrier gas and into the condensing train where they are cooled and recovered. The dryer is fitted with a filtration system that keeps the radioactive constituents from migrating to the condensate. As such, the waste is separated into hazardous liquid and radioactive solid components, allowing for disposal of these streams at a permitted incinerator or a radioactive materials landfill, respectively. The VAC*TRAX system is designed to be highly mobile, while minimizing the operational costs with a simple, robust process. These factors allow for treatment of small waste streams at a reasonable cost.

  5. Development of a thermal desorption modulator for gas chromatography

    NARCIS (Netherlands)

    Geus, H.J.; Boer, de J.; Brinkman, U.A.Th.

    1997-01-01

    The separation space in gas chromatography can be enhanced dramatically by the comprehensive coupling of two independent separation dimensions. An interface between the two columns must accumulate analytes eluting from the first dimension, focus them and at the appropriate moment transfer them to th

  6. Thermal desorption of CH4 retained in CO2 ice

    CERN Document Server

    Luna, R; Domingo, M; Satorre, M A

    2008-01-01

    CO2 ices are known to exist in different astrophysical environments. In spite of this, its physical properties (structure, density, refractive index) have not been as widely studied as those of water ice. It would be of great value to study the adsorption properties of this ice in conditions related to astrophysical environments. In this paper, we explore the possibility that CO2 traps relevant molecules in astrophysical environments at temperatures higher than expected from their characteristic sublimation point. To fulfil this aim we have carried out desorption experiments under High Vacuum conditions based on a Quartz Crystal Microbalance and additionally monitored with a Quadrupole Mass Spectrometer. From our results, the presence of CH4 in the solid phase above the sublimation temperature in some astrophysical scenarios could be explained by the presence of several retaining mechanisms related to the structure of CO2 ice.

  7. Thermal desorption of helium from homogeneously implanted graphite

    Science.gov (United States)

    Jung, P.; Schroeder, H.

    1991-11-01

    Super-fine grain graphite (FGG) and pyrolytic carbon (PYC) of thicknesses around 200 μm were homogeneously implanted at room temperature with α-particles (0.5 MeV ≤ Eα ≤ 22 MeV). Thermal helium desorption spectrometry in the temperature range from 400 to 1900 K can be described by diffusion kinetics with an activation energy of 1.1 eV in FGG and about 0.75 eV in PYC. Desorption during temperature ramping at a constant rate of 0.83 K/s also shows significant differences of the two graphite species. It is found that in FGG and especially in PYC a considerable fraction of the implanted helium is retained even beyond 1000 K. This is in contrast to results reported after low energy implantations to high doses for various graphite species.

  8. Thermal desorption of circumstellar and cometary ice analogs

    CERN Document Server

    Martín-Doménech, Rafael; Bueno, Juan; Goesmann, Fred

    2014-01-01

    Thermal annealing of interstellar ices takes place in several stages of star formation. Knowledge of this process comes from a combination of astronomical observations and laboratory simulations under astrophysically relevant conditions. For the first time we present the results of temperature programmed desorption (TPD) experiments with pre-cometary ice analogs composed of up to five molecular components: H2 O, CO, CO2, CH3 OH, and NH3 . The experiments were performed with an ultra-high vacuum chamber. A gas line with a novel design allows the controlled preparation of mixtures with up to five molecular components. Volatiles desorbing to the gas phase were monitored using a quadrupole mass spectrometer, while changes in the ice structure and composition were studied by means of infrared spectroscopy. The TPD curves of water ice containing CO, CO2, CH3 OH, and NH3 present desorption peaks at temperatures near those observed in pure ice experiments, volcano desorption peaks after water ice crystallization, and...

  9. Man creation had began since the creation of the first biological ...

    African Journals Online (AJOL)

    Man creation had began since the creation of the first biological material very likely in ... of holy Qur'an verses related to the topic of man creation, the man creation had ... paper I will show that this conclusion is not in discordance with science.

  10. New venture creation as emerging interdependencies

    DEFF Research Database (Denmark)

    van Oorschot, Robin; Gottlieb, Frederik

    2015-01-01

    What is ‘it’ which actually takes place in the process of the creation of a new venture? Traditional research would focus on the creation of ‘the product’ or the venture. In this paper, we focus on the creation of ‘new meaning’ and emerging interdependencies between people in the process of new...... venture creation. Taking on an auto- ethnographic approach we co-construct, describe and analyse two narratives which on different levels, explore the notion of interdependency emerging in the process of creating a new venture. In our narrative approach we channel our new venture creation research...

  11. Phonon creation by gravitational waves

    CERN Document Server

    Sabín, Carlos; Ahmadi, Mehdi; Fuentes, Ivette

    2014-01-01

    We show that gravitational waves create phonons in a Bose-Einstein condensate (BEC). A traveling spacetime distortion produces particle creation resonances that correspond to the dynamical Casimir effect in a BEC phononic field contained in a cavity-type trap. We propose to use this effect to detect gravitational waves. The amplitude of the wave can be estimated applying recently developed relativistic quantum metrology techniques. We provide the optimal precision bound on the estimation of the wave's amplitude. Finally, we show that the parameter regime required to detect gravitational waves with this technique is within experimental reach.

  12. Knowledge Creation Through Development Projects

    DEFF Research Database (Denmark)

    Laursen, Erik

    2010-01-01

    or implemented by the organization during the projects to the routine activities of the organization after the finishing of projects ?. In the paper a typology of development projects is presented and discussed as different ways of framing the organizational learning processes, The paper is based on an empirical....... The theoretical frame of analysis has references to Nanoka & Takeuchi (knowledge creation through the transformation of the forms of the knowledge), Argyris and Ellström (the distinction between modes of correction and modes of development) ....

  13. Knowledge Sharing is Knowledge Creation

    DEFF Research Database (Denmark)

    Greve, Linda

    2015-01-01

    Knowledge sharing and knowledge transfer are important to knowledge communication. However when groups of knowledge workers engage in knowledge communication activities, it easily turns into mere mechanical information processing despite other ambitions. This article relates literature of knowledge...... reducing complexity and dividing knowledge into to dichotomies or hierarchies, knowledge workers should be enabled to use different strategies for knowledge sharing, -transfer and –creation depending on the task and the nature of the knowledge. However if the ambition is to have a strategy for sharing...

  14. Value Creation in Cryptocurrency Networks

    DEFF Research Database (Denmark)

    Kazan, Erol; Tan, Chee-Wee; Lim, Eric T. K.

    2015-01-01

    advances a unified theoretical framework for identifying and investigating how cryptocurrency companies configure value through digital business models. This framework is then employed, via multiple case studies, to examine digital business models of companies within the bitcoin network. Findings suggest...... that companies within the bitcoin network exhibits six generic digital business models. These six digital business models are in turn driven by three modes of value configurations with their own distinct logic for value creation and mechanisms for value capturing. A key finding of this study is that value...

  15. 吸附-热解吸法与气相色谱-质谱法联用测定蚊香烟雾中的有机化合物%Determination of Organic Compounds in the Smog of Mosquito-Repellent Incense by Adsorption-Thermal Desorption-GC/MS

    Institute of Scientific and Technical Information of China (English)

    刘秀华; 钟志京; 孟丹; 丁兰岚; 田军华

    2012-01-01

    利用吸附-热解吸法与气相色谱-质谱法联用,对两种固体蚊香烟气中的有机成分进行定性和半定量分析.在两种固体蚊香烟气中共检测出52种挥发性成分,包括酚类、醇类、醛类以及脂肪烃和芳香烃等多种化合物,其中的部分化合物对人体有毒害作用.蚊香A烟气中含量较多的成分为右旋烯丙菊酯(30.06%)、1,6-脱水-β-D-吡喃葡萄糖(19.4%)和甘菊环(13.9%)等;蚊香B烟气中含量较多的成分为1,6-脱水-β-D-吡喃葡萄糖(24.4%)、甘菊环(14.4%)和正十四烷(5.91%)等.%The organic components in the smog of mosquito-repellent incense were analyzed qualitatively and semi-quantitatively by adsorption-thermal desorption with gas chromatog-raphy-mass spectrometry. 52 kinds of compounds are identified in two kinds of solid mosquito-repellent incenses, including phenolic compounds, alcohols, aldehydes, aliphatic hydrocarbons, aromatic hydrocarbons and so on. Some compounds are poisonous to people's health. The principal components in the smog of mosquito-repellent incense A are allethrin (30.06%), l,6-Anhydro-β-D-glucopyranose(19. 4%), azulene(13. 9%) , while the principal components are 1,6-Anhydro-β-D-glucopyranose(24. 4%), azulene(14. 4%), tetrade-cane(5. 91%) for the mosquito-repellent incense B.

  16. Particle Creation in Bouncing Cosmologies

    CERN Document Server

    Celani, Diogo C F; Vitenti, Sandro D P

    2016-01-01

    We investigate scalar particle creation in a set of bouncing models where the bounce occurs due to quantum cosmological effects described by the Wheeler-DeWitt equation. The scalar field can be either conformally or minimally coupled to gravity, and it can be massive or massless, without self interaction. The analysis is made for models containing a single radiation fluid, and for the more realistic case of models containing the usual observed radiation and dust fluids, which can fit most of the observed features of our Universe, including an almost scale invariant power spectrum of scalar cosmological perturbations. In the conformal coupling case, the particle production is negligible. In the minimal coupling case, for massive particles, the results point to the same physical conclusion within observational constraints: particle production is most important at the bounce energy scale, and it is not sensitive neither to its mass nor whether there is dust in the background model. The only caveat is the case wh...

  17. Remote creation of quantum coherence

    Science.gov (United States)

    Ma, Teng; Zhao, Ming-Jing; Fei, Shao-Ming; Long, Gui-Lu

    2016-10-01

    We study remote creation of coherence (RCC) for a quantum system, A, with the help of quantum operations on another system, B, and one-way classical communication. We show that all the nonincoherent quantum states are useful for RCC and all the incoherent-quantum states are not. The necessary and sufficient conditions of RCC for the quantum operations on system B are presented for pure states. The upper bound of average RCC is derived, giving a relation among the entanglement (concurrence), the RCC of the given quantum state, and the RCC of the corresponding maximally entangled state. Moreover, for two-qubit systems we find a simple factorization law for the average remote-created coherence.

  18. Analysing performance through value creation

    Directory of Open Access Journals (Sweden)

    Adrian TRIFAN

    2015-12-01

    Full Text Available This paper draws a parallel between measuring financial performance in 2 variants: the first one using data offered by accounting, which lays emphasis on maximizing profit, and the second one which aims to create value. The traditional approach to performance is based on some indicators from accounting data: ROI, ROE, EPS. The traditional management, based on analysing the data from accounting, has shown its limits, and a new approach is needed, based on creating value. The evaluation of value based performance tries to avoid the errors due to accounting data, by using other specific indicators: EVA, MVA, TSR, CVA. The main objective is shifted from maximizing the income to maximizing the value created for shareholders. The theoretical part is accompanied by a practical analysis regarding the creation of value and an analysis of the main indicators which evaluate this concept.

  19. Facilitating Value Co-Creation

    DEFF Research Database (Denmark)

    Veith, Anne; Assaf, Albert; Josiassen, Alexander

    2013-01-01

    ) introduced a new dominant logic in the marketing literature, the Service-Dominant Logic (S-D Logic), in which service, interactions, and enhanced experiences help create value, and this potential for value is what attracts consumers. Therefore organizations must be customer-centric in order to facilitate...... unique, positive experiences. As the name indicates, both organizations and consumers (should) obtain value when co-creating, which is why both parties are willing to increase their degree of involvement, e.g. spending more resources, sharing tacit knowledge, etc., because a high degree of involvement....... Through an exploratory qualitative study, 9 facilitators for B2C value co-creation were uncovered. The study was set in the creative industries. The 9 facilitators are a combination of the main facilitators found in the literature review and the ones found through the empirical research. The 9...

  20. Value Creation in Cryptocurrency Networks

    DEFF Research Database (Denmark)

    Kazan, Erol; Tan, Chee-Wee; Lim, Eric T. K.

    2015-01-01

    -chain and value-network driven business models commercialize their products and services for each value unit transfer, whereas commercialization for value-shop driven business models is realized through the subsidization of direct users by revenue generating entities. This study contributes to extant literature...... advances a unified theoretical framework for identifying and investigating how cryptocurrency companies configure value through digital business models. This framework is then employed, via multiple case studies, to examine digital business models of companies within the bitcoin network. Findings suggest...... that companies within the bitcoin network exhibits six generic digital business models. These six digital business models are in turn driven by three modes of value configurations with their own distinct logic for value creation and mechanisms for value capturing. A key finding of this study is that value...

  1. Money creation in a random matching model

    OpenAIRE

    Alexei Deviatov

    2004-01-01

    I study money creation in versions of the Trejos-Wright (1995) and Shi (1995) models with indivisible money and individual holdings bounded at two units. I work with the same class of policies as in Deviatov and Wallace (2001), who study money creation in that model. However, I consider an alternative notion of implementability–the ex ante pairwise core. I compute a set of numerical examples to determine whether money creation is beneficial. I find beneficial e?ects of money creation if indiv...

  2. Serum/plasma methylmercury determination by isotope dilution gas chromatography-inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, Douglas C., E-mail: douglas.baxter@alsglobal.com [ALS Scandinavia AB, Aurorum 10, 977 75 Lulea (Sweden); Faarinen, Mikko [ALS Scandinavia AB, Aurorum 10, 977 75 Lulea (Sweden); Osterlund, Helene; Rodushkin, Ilia [ALS Scandinavia AB, Aurorum 10, 977 75 Lulea (Sweden); Division of Geosciences, Lulea University of Technology, 977 87 Lulea (Sweden); Christensen, Morten [ALS Scandinavia AB, Maskinvaegen 2, 183 53 Taeby (Sweden)

    2011-09-09

    Highlights: {center_dot} We determine methylmercury in serum and plasma using isotope dilution calibration. {center_dot} Separation by gas chromatography and detection by inductively coupled plasma mass spectrometry. {center_dot} Data for 50 specimens provides first reference range for methylmercury in serum. {center_dot} Serum samples shown to be stable for 11 months in refrigerator. - Abstract: A method for the determination of methylmercury in plasma and serum samples was developed. The method uses isotope dilution with {sup 198}Hg-labeled methylmercury, extraction into dichloromethane, back-extraction into water, aqueous-phase ethylation, purge and trap collection, thermal desorption, separation by gas chromatography, and mercury isotope specific detection by inductively coupled plasma mass spectrometry. By spiking 2 mL sample with 1.2 ng tracer, measurements in a concentration interval of (0.007-2.9) {mu}g L{sup -1} could be performed with uncertainty amplification factors <2. A limit of quantification of 0.03 {mu}g L{sup -1} was estimated at 10 times the standard deviation of concentrations measured in preparation blanks. Within- and between-run relative standard deviations were <10% at added concentration levels of 0.14 {mu}g L{sup -1}, 0.35 {mu}g L{sup -1} and 2.8 {mu}g L{sup -1}, with recoveries in the range 82-110%. Application of the method to 50 plasma/serum samples yielded a median (mean; range) concentration of methylmercury of 0.081 (0.091; <0.03-0.19) {mu}g L{sup -1}. This is the first time methylmercury has been directly measured in this kind of specimen, and is therefore the first estimate of a reference range.

  3. Open string pair creation from worldsheet instantons

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, Christian [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Muehlenberg 1, D-14476 Potsdam (Germany); Torrielli, Alessandro [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, Leuvenlaan 4, 3584 CE Utrecht (Netherlands)

    2010-10-08

    Worldline instantons provide a particularly elegant way to derive Schwinger's well-known formula for the pair creation rate due to a constant electric field in quantum electrodynamics. In this communication, we show how to extend this method to the corresponding problem of open string pair creation. (fast track communication)

  4. Quantum Creation of Topological Black Hole

    CERN Document Server

    Wu Zhong Chao

    2000-01-01

    The constrained instanton method is used to study quantum creation of a vacuum or charged topological black hole. At the WKB level, the relative creation probability is the exponential of a quarter sum of the horizon areas associated with the seed instanton.

  5. The Future of Co-Creation

    DEFF Research Database (Denmark)

    Seppa, Marko; Tanev, Stoyan

    2011-01-01

    The objective of this article is to provide a brief summary of the key directions in value co-creation research that have emerged in the last 10 years. It points to several emerging streams in value co-creation research including: i) general management perspective; ii) new product development...

  6. Particle creation in bouncing cosmologies

    Science.gov (United States)

    Celani, Diogo C. F.; Pinto-Neto, Nelson; Vitenti, Sandro D. P.

    2017-01-01

    We investigate scalar particle creation in a set of bouncing models where the bounce occurs due to quantum cosmological effects described by the Wheeler-DeWitt equation. The scalar field can be either conformally or minimally coupled to gravity, and it can be massive or massless, without self-interaction. The analysis is made for models containing a single radiation fluid and for the more realistic case of models containing the usual observed radiation and dust fluids, which can fit most of the observed features of our universe, including an almost scale invariant power spectrum of scalar cosmological perturbations. In the conformal coupling case, the particle production is negligible. In the minimal coupling case, for massive particles, the results point to the same physical conclusion within observational constraints: particle production is most important at the bounce energy scale, and it is not sensitive either to its mass or to whether there is dust in the background model. The only caveat is the case where the particle mass is larger than the bounce energy scale. On the other hand, the energy density of produced massive particles depend on their masses and the energy scale of the bounce. For very large masses and deep bounces, this energy density may overcome that of the background. In the case of massless particles, the energy density of produced particles can become comparable to the background energy density only for bounces occurring at energy scales comparable to the Planck scale or above, which lies beyond the scope of this paper: we expect that the simple Wheeler-DeWitt approach we are using should be valid only at scales a few orders of magnitude below the Planck energy. Nevertheless, in the case in which dust is present, there is an infrared divergence, which becomes important only for scales much larger than today's Hubble radius.

  7. Ion mobility spectrometry as a simple and rapid method to measure the plasma propofol concentrations for intravenous anaesthesia monitoring

    Science.gov (United States)

    Wang, Xin; Zhou, Qinghua; Jiang, Dandan; Gong, Yulei; Li, Enyou; Li, Haiyang

    2016-11-01

    The plasma propofol concentration is important information for anaesthetists to monitor and adjust the anaesthesia depth for patients during a surgery operation. In this paper, a stand-alone ion mobility spectrometer (IMS) was constructed for the rapid measurement of the plasma propofol concentrations. Without any sample pre-treatment, the plasma samples were dropped on a piece of glass microfiber paper and then introduced into the IMS cell by the thermal desorption directly. Each individual measurement could be accomplished within 1 min. For the plasma propofol concentrations from 1 to 12 μg mL-1, the IMS response was linear with a correlation coefficient R2 of 0.998, while the limit of detection was evaluated to be 0.1 μg mL-1. These measurement results did meet the clinical application requirements. Furthermore, other clinically-often-used drugs, including remifentanil, flurbiprofen and atracurium, were found no significant interference with the qualitative and quantitative analysis of the plasma propofol. The plasma propofol concentrations measured by IMS were correlated well with those measured by the high performance liquid chromatography (HPLC). The results confirmed an excellent agreement between these two methods. Finally, this method was applied to monitor the plasma propofol concentrations for a patient undergoing surgery, demonstrating its capability of anaesthesia monitoring in real clinical environments.

  8. Constrained instanton and black hole creation

    Institute of Scientific and Technical Information of China (English)

    WU Zhongchao; XU Donghui

    2004-01-01

    A gravitational instanton is considered as the seed for the creation of a universe. However, there exist too few instantons. To include many interesting phenomena in the framework of quantum cosmology, the concept of constrained gravitational instanton is inevitable. In this paper we show how a primordial black hole is created from a constrained instanton. The quantum creation of a generic black hole in the closed or open background is completely resolved. The relation of the creation scenario with gravitational thermodynamics and topology is discussed.

  9. Interactivity, Game Creation, Design, Learning, and Innovation

    DEFF Research Database (Denmark)

    This book constitutes the proceedings of two conferences: The 5th International Conference on ArtsIT, Interactivity and Game Creation (ArtsIT 2016) and the First International Conference on Design, Learning and Innovation (DLI 2016). ArtsIT is reflecting trends in the expanding field of digital art......, interactive art, and how game creation is considered an art form. The decision was made to augment the title of ArtsIT to be in future known as “The International Conference on Interactivity, Game Creation, Design, Learning, and Innovation”. The event was hosted in Esbjerg, Denmark in May 2016 and attracted...

  10. Role of surface temperature in fluorocarbon plasma-surface interactions

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Caleb T.; Overzet, Lawrence J.; Goeckner, Matthew J. [Department of Electrical Engineering, University of Texas at Dallas, PO Box 830688, Richardson, TX 75083 (United States)

    2012-07-15

    This article examines plasma-surface reaction channels and the effect of surface temperature on the magnitude of those channels. Neutral species CF{sub 4}, C{sub 2}F{sub 6}, and C{sub 3}F{sub 8} are produced on surfaces. The magnitude of the production channel increases with surface temperature for all species, but favors higher mass species as the temperature is elevated. Additionally, the production rate of CF{sub 2} increases by a factor of 5 as the surface temperature is raised from 25 Degree-Sign C to 200 Degree-Sign C. Fluorine density, on the other hand, does not change as a function of either surface temperature or position outside of the plasma glow. This indicates that fluorine addition in the gas-phase is not a dominant reaction. Heating reactors can result in higher densities of depositing radical species, resulting in increased deposition rates on cooled substrates. Finally, the sticking probability of the depositing free radical species does not change as a function of surface temperature. Instead, the surface temperature acts together with an etchant species (possibly fluorine) to elevate desorption rates on that surface at temperatures lower than those required for unassisted thermal desorption.

  11. Universe creation on a computer

    Science.gov (United States)

    McCabe, Gordon

    The purpose of this paper is to provide an account of the epistemology and metaphysics of universe creation on a computer. The paper begins with F.J. Tipler's argument that our experience is indistinguishable from the experience of someone embedded in a perfect computer simulation of our own universe, hence we cannot know whether or not we are part of such a computer program ourselves. Tipler's argument is treated as a special case of epistemological scepticism, in a similar vein to 'brain-in-a-vat' arguments. It is argued that Tipler's hypothesis that our universe is a program running on a digital computer in another universe, generates empirical predictions, and is therefore a falsifiable hypothesis. The computer program hypothesis is also treated as a hypothesis about what exists beyond the physical world, and is compared with Kant's metaphysics of noumena. It is argued that if our universe is a program running on a digital computer, then our universe must have compact spatial topology, and the possibilities of observationally testing this prediction are considered. The possibility of testing the computer program hypothesis with the value of the density parameter Ω0 is also analysed. The informational requirements for a computer to represent a universe exactly and completely are considered. Consequent doubt is thrown upon Tipler's claim that if a hierarchy of computer universes exists, we would not be able to know which 'level of implementation' our universe exists at. It is then argued that a digital computer simulation of a universe, or any other physical system, does not provide a realisation of that universe or system. It is argued that a digital computer simulation of a physical system is not objectively related to that physical system, and therefore cannot exist as anything else other than a physical process occurring upon the components of the computer. It is concluded that Tipler's sceptical hypothesis, and a related hypothesis from Bostrom, cannot be

  12. Taking Stock of Project Value Creation

    DEFF Research Database (Denmark)

    Laursen, Markus; Svejvig, Per

    2014-01-01

    This paper presents the outcome of a literature review through classifying and analyzing 59 publications in project value creation literature. The analysis led to five distinct categories: Benefit Realization Management (BRM) and techniques, broad value perspective, value time frame, engineering...

  13. Fabrics China Creation Show Held in Shanghai

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    On August 5-6th,the 3rd Fabrics China Creation Show (one series events of Reach & Touch),organized by China National Textile & Apparel Council and National Textile Development Center,was held in Shanghai,

  14. Value creation and the entrepreneurial business

    OpenAIRE

    Spivey, Michael F.; Jeffrey J. McMillan

    2002-01-01

    The need to finance high growth and manage the interests and needs of investors makes value creation a critical concern for entrepreneurial businesses. Almost any financial endeavor, such as attracting new investors or making investment decisions, necessitates the consideration of the equity value created by the endeavor. The perceived value creation, for example, has a direct effect on the percentage of the firm outside investors will require if they are to invest in the business. Measuring ...

  15. Black Hole - Moving Mirror II: Particle Creation

    OpenAIRE

    Good, Michael R. R.; Anderson, Paul R.; Evans, Charles R.

    2015-01-01

    There is an exact correspondence between the simplest solution to Einstein's equations describing the formation of a black hole and a particular moving mirror trajectory. In both cases the Bogolubov coefficients in 1+1 dimensions are identical and can be computed analytically. Particle creation is investigated by using wave packets. The entire particle creation history is computed, incorporating the early-time non-thermal emission due to the formation of the black hole (or the early-time acce...

  16. Service systems for value co-creation

    OpenAIRE

    Smith, Laura A.; Ng, Irene C. L.

    2012-01-01

    Over the last few decades there has been growing interest from both marketing researchers and practitioners in the creation of value (Eggert & Ulaga, 2002). In a series of publications on the Service-Dominant Logic (S-D Logic), Vargo and Lusch (2004: 2008) review the economic foundations that underpin how value creation is understood. In doing so, they put forward a number of propositions, which have had a significant impact on current management theory and practice. The central tenant of val...

  17. Deuterium retention and surface modifications of nanocrystalline tungsten films exposed to high-flux plasma

    Energy Technology Data Exchange (ETDEWEB)

    Hoen, M.H.J. ' t [FOM Institute DIFFER (Dutch Institute for Fundamental Energy Research), Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster, 3439 MN Nieuwegein (Netherlands); Dellasega, D.; Pezzoli, A.; Passoni, M. [Politecnico di Milano, EURATOM-ENEA-CNR Association, Milano (Italy); Kleyn, A.W., E-mail: A.W.Kleijn@uva.nl [FOM Institute DIFFER (Dutch Institute for Fundamental Energy Research), Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster, 3439 MN Nieuwegein (Netherlands); University of Amsterdam, Science Park 904, NL-1098 XH Amsterdam (Netherlands); Center of Interface Dynamics for Sustainability, CDCST, CAEP, Chengdu, Sichuan 610207 (China); Zeijlmans van Emmichoven, P.A. [FOM Institute DIFFER (Dutch Institute for Fundamental Energy Research), Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster, 3439 MN Nieuwegein (Netherlands)

    2015-08-15

    Highlights: • The films withstand the intense plasma exposure maintaining overall integrity. • An increase of deuterium retention was observed with decreasing tungsten density. • Formation of micrometer-sized blisters as well as structures on the nanometer scale depending on the layer type. - Abstract: Deuterium retention studies are presented for nanostructured tungsten films exposed to high-flux deuterium plasmas. Thin tungsten films of ∼1 μm thickness were deposited with pulsed laser deposition (PLD) on bulk tungsten. Surface modifications were studied with scanning electron microscopy and deuterium retention with thermal desorption spectroscopy. Three types of PLD films with different densities and crystallinity were studied after exposure to deuterium plasmas. The surface temperature ranged from about 460 K at the periphery to about 520 K in the centre of the targets. The films withstand the intense plasma exposure well and maintain their overall integrity. An increase of deuterium retention is observed with decreasing tungsten density and crystallite size. We found that the filling of these thin films with deuterium is significantly faster than for pre-damaged polycrystalline tungsten. We observed formation of micrometer-sized blisters as well as structures on the nanometer scale, both depending on the layer type.

  18. Logistics potentials in business competitive advantage creation

    Directory of Open Access Journals (Sweden)

    Rafał Matwiejczuk

    2013-12-01

    Full Text Available Background: Companies constantly search for ways to achieve and sustain long-term competitive advantage. Among the factors influencing the competitive advantage creation there are so called logistics potentials, which constitute a component part of a business strategic potentials. Logistics resources, logistics capabilities and logistics competences are the main components of the logistics potentials structure and hierarchy. Methods: In order to recognize the logistics potentials which determine the competitive advantage creation one may use the assumptions and elements of contemporary management concepts, including strategic management. In particular the article deals with Resource-Based View (RBV, Dynamic Capabilities Concept (DCC and - first of all - Competence-Based Management (CBM. Results and conclusions: Several significant research projects have presented a wide scope and a large number of possibilities of logistics potentials (and logistics competences in particular influence on business competitive advantage creation. The article briefly presents the research results conducted by: (1 Michigan State University (USA, (2 European Logistics Association (ELA in cooperation with A.T. Kearney, (3 Computer Sciences Corporation and (4 Capgemini. The research results have pointed out to differentiated but at the same distinctive symptoms of logistics competences influence on competitive advantage creation. The article also refers to the results of the research carried out by the Chair of Logistics & Marketing at Opole University (Poland in companies operating in Poland. The research has been mainly dealing with the significance of logistics competences in competitive advantage creation.

  19. Inflationary models driven by adiabatic matter creation

    CERN Document Server

    Abramo, L R W

    1996-01-01

    The flat inflationary dust universe with matter creation proposed by Prigogine and coworkers is generalized and its dynamical properties are reexamined. It is shown that the starting point of these models depends critically on a dimensionless parameter \\Sigma, closely related to the matter creation rate \\psi. For \\Sigma bigger or smaller than unity flat universes can emerge, respectively, either like a Big-Bang FRW singularity or as a Minkowski space-time at t=-\\infty. The case \\Sigma=1 corresponds to a de Sitter-type solution, a fixed point in the phase diagram of the system, supported by the matter creation process. The curvature effects have also been investigated. The inflating de Sitter is a universal attractor for all expanding solutions regardless of the initial conditions as well as of the curvature parameter.

  20. Entrepreneurship, Job Creation and Wage Growth

    DEFF Research Database (Denmark)

    Malchow-Møller, Nikolaj; Schjerning, Bertel; Sørensen, Anders

    2011-01-01

    This paper analyses the importance of entrepreneurs in terms of job creation and wage growth. Relying on unique data that cover all establishments, firms and individuals in the Danish private sector, we are able to distil a number of different subsets from the total set of new establishments......—subsets which allow us to more precisely capture the “truly new” or “entrepreneurial” establishments than has been possible in previous studies. Using these data, we find that while new establishments in general account for one-third of the gross job creation in the economy, entrepreneurial establishments...... are responsible for around 25% of this, and thus only account for about 8% of total gross job creation in the economy. However, entrepreneurial establishments seem to generate more additional jobs than other new establishments in the years following entry. Finally, the jobs generated by entrepreneurial...

  1. Entrepreneurship, Job Creation, and Wage Growth

    DEFF Research Database (Denmark)

    Malchow-Møller, Nikolaj; Schjerning, Bertel; Sørensen, Anders

    This paper analyses the importance of entrepreneurs for job creation and wage growth. Relying on unique data that cover all establishments, firms and individuals in the Danish private sector, we are able to distil a number of different subsets from the total set of new establishments - subsets...... which allow us to more precisely capture the "truly new" or "entrepreneurial" establishments than in previous studies. Using these data, we find that while new establishments in general account for one third of the gross job creation in the economy, entrepreneurial establishments are responsible...... for around 25% of this, and thus only account for about 8% of total gross job creation in the economy. However, entrepreneurial establishments seem to generate more additional jobs than other new establishments in the years following entry. Finally, the jobs generated by entrepreneurial establishments...

  2. Aquinas and Contemporary Cosmology: Creation and Beginnings

    Science.gov (United States)

    Carroll, William E.

    Discussions in the Middle Ages about creation and the temporal beginning of the world involved sophisticated analyses in theology, metaphysics, and natural philosophy. Mediaeval insights on this subject, especially Thomas Aquinas' defense of the intelligibility of an eternal, created universe, can help to clarify reflections about the philosophical and theological implications of contemporary cosmological theories: from the "singularity" of the Big Bang, to "quantum tunneling from nothing," to multiverse scenarios. Thomas' insights help us to see the value of Georges Lemaître's insistence that his cosmological reflections must be kept separate from an analysis of creation. This essay will look at different senses of "beginning" and examine the claim that creation, in its fundamental meaning, tells us nothing about whether there is a temporal beginning to the universe. Multiverse models, like that recently proposed by Stephen Hawking and Leonard Mlodinow, may challenge certain views of a Grand Designer, but not of a Creator.

  3. Entrepreneurship, job creation and wage growth

    DEFF Research Database (Denmark)

    Malchow-Møller, Nikolaj; Schjerning, Bertel; Sørensen, Anders

    2011-01-01

      This paper analyses the importance of entrepreneurs for job creation and wage growth. Relying on unique data that cover all establishments, firms and individuals in the Danish private sector, we are able to distil a number of different subsets from the total set of new establishments - subsets...... which allow us to more precisely capture the "truly new" or "entrepreneurial" establishments than in previous studies. Using these data, we find that while new establishments in general account for one third of the gross job creation in the economy, entrepreneurial establishments are responsible...... for around 25% of this, and thus only account for about 8% of total gross job creation in the economy. However, entrepreneurial establishments seem to generate more additional jobs than other new establishments in the years following entry. Finally, the jobs generated by entrepreneurial establishments...

  4. View Creation for Queriesin Object Oriented Databases

    Institute of Scientific and Technical Information of China (English)

    Rajesh Narang; K.D. Sharma

    1999-01-01

    A view in object oriented databasescorresponds to virtual schema with restructured generalization anddecomposition hierarchies. Numbers of view creation methodologies havebeen proposed. A major drawback of existing methodologies is that theydo not maintain the closure property. That is, the result of a querydoes not have the same semantics as embodied in the object oriented datamodel. Therefore, this paper presents a view creation methodology thatderives a class in response to a user's query, integrates derived classin global schema (i.e., considers the problem of classes moving in classhierarchy) and selects the required classes from global schema to createthe view for user's query. Novel idea of view creation includes: (a) anobject algebra for class derivation and customization (where the derivedclasses in terms of object instances and procedure/methods are studied),(b) maintenance of closure property, and (c) classification algorithmwhich provides mechanism to deal with the problem of a class moving in aclass hierarchy.

  5. Distinctive Dynamic Capabilities for New Business Creation

    DEFF Research Database (Denmark)

    Rosenø, Axel; Enkel, Ellen; Mezger, Florian

    2013-01-01

    This study examines the distinctive dynamic capabilities for new business creation in established companies. We argue that these are very different from those for managing incremental innovation within a company's core business. We also propose that such capabilities are needed in both slow...... and fast-paced industries, and that similarities exist across industries. Hence, the study contributes to dynamic capabilities literature by: 1) identifying the distinctive dynamic capabilities for new business creation; 2) shifting focus away from dynamic capabilities in environments characterised by high...... clock-speed and uncertainty towards considering dynamic capabilities for the purpose of developing new businesses, which also implies a high degree of uncertainty. Based on interviews with 33 companies, we identify distinctive dynamic capabilities for new business creation, find that dynamic...

  6. Dynamic wormholes with particle creation mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Supriya; Chakraborty, Subenoy [Jadavpur University, Department of Mathematics, Kolkata (India)

    2015-01-01

    The present work deals with a spherically symmetric space-time which is asymptotically (at spatial infinity) FRW space-time and represents wormhole configuration: The matter component is divided into two parts - (a) dissipative but homogeneous and isotropic fluid, and (b) an inhomogeneous and anisotropic barotropic fluid. Evolving wormhole solutions are obtained when isotropic fluid is phantom in nature and there is a big rip singularity at the end. Here the dissipative phenomena is due to the particle creation mechanism in non-equilibrium thermodynamics. Using the process to be adiabatic, the dissipative pressure is expressed linearly to the particle creation rate. For two choices of the particle creation rate as a function of the Hubble parameter, the equation of state parameter of the isotropic fluid is constrained to be in the phantom domain, except in one choice, it is possible to have wormhole configuration with normal isotropic fluid. (orig.)

  7. Organizational Values and Innovative Organizational Knowledge Creation

    Directory of Open Access Journals (Sweden)

    Lilian Aparecida Pasquini Miguel

    2009-01-01

    Full Text Available Innovation is a source of competitive advantage and is based on the continuous creation of organizational knowledge, which is supported by the individual learning. The individual learning of traditional / comportamentalist and constructivist nature can be understood, by extension, as organizational learning. The knowledge can be innovative if, along with the enabling conditions that characterize it - intention, fluctuation or chaos, autonomy, redundancy and variety of requirements – the process of learning is based on a constructivist nature, the only one capable to generate new learning solutions. The organizational values are beliefs that guide the organizations behavior and constitute motivational goals. This work had as aim to identify the relationship between organizational values and the creation of knowledge. The descriptive exploratory research used the quantitative method. The organizational values appeared in this study mainly associated to the knowledge creation aspects in the internal sphere of the organizations. The orientation towards the external environment appeared less related to the organizational values.

  8. Black Hole - Moving Mirror II: Particle Creation

    CERN Document Server

    Good, Michael R R; Evans, Charles R

    2015-01-01

    There is an exact correspondence between the simplest solution to Einstein's equations describing the formation of a black hole and a particular moving mirror trajectory. In both cases the Bogolubov coefficients in 1+1 dimensions are identical and can be computed analytically. Particle creation is investigated by using wave packets. The entire particle creation history is computed, incorporating the early-time non-thermal emission due to the formation of the black hole (or the early-time acceleration of the moving mirror) and the evolution to a Planckian spectrum.

  9. The demonism of creation in Goethe's philosophy

    Directory of Open Access Journals (Sweden)

    Nicolae Râmbu

    2012-12-01

    Full Text Available Goethe's philosophy of creativity revolves around what he called das Dämonische. This essay is not meant as a definition or an explanation of demonic creation, but instead presents a demonic work par excellence, as the term "demonic" is defined by Goethe in the Elegy from Marienbad. The process of the creation of this work, as it is described by Goethe, also represents a strange exorcism, as the entire daemonic creative force of the author is transposed in this lyrical masterpiece of German and universal literature. After writing the Elegy Goethe, it is no longer demonic.

  10. Designing Learning for Co-Creation

    DEFF Research Database (Denmark)

    Gnaur, Dorina; Larsen-Nielsen, Inger Marie

    2017-01-01

    educational frameworks that respond to the societal demand for co-creation, particularly within the public welfare sector? First, they focus on which organisational and individual requirements an HE learning design should take into account in order to support the diffusion of co-creation competences....... Then they argue for the need to integrate these considerations in the learning design and demonstrate a practical application in the form of a didactical design. They call this a hybrid learning design, in that it takes advantage of technological developments to mediate co-creative learning in multiple learning...

  11. Particle creation by peak electric field

    CERN Document Server

    Adorno, T C; Gitman, D M

    2016-01-01

    The particle creation by the so-called peak electric field is considered. The latter field is a combination of two exponential parts, one exponentially-increasing and another exponentially-decreasing. We find exact solutions of the Dirac equation with the field under consideration with appropriate asymptotic conditions and calculate all the characteristics of particle creation effect, in particular, differential mean numbers of created particle, total number of created particles, and the probability for a vacuum to remain a vacuum. Characteristic asymptotic regimes are discussed in detail and a comparison with the pure asymptotically decaying field is considered.

  12. Particle creation by peak electric field

    Energy Technology Data Exchange (ETDEWEB)

    Adorno, T.C. [Tomsk State University, Department of Physics, Tomsk (Russian Federation); Gavrilov, S.P. [Tomsk State University, Department of Physics, Tomsk (Russian Federation); Herzen State Pedagogical University of Russia, Department of General and Experimental Physics, St. Petersburg (Russian Federation); Gitman, D.M. [Tomsk State University, Department of Physics, Tomsk (Russian Federation); P. N. Lebedev Physical Institute, Moscow (Russian Federation); University of Sao Paulo, Institute of Physics, CP 66318, Sao Paulo, SP (Brazil)

    2016-08-15

    The particle creation by the so-called peak electric field is considered. The latter field is a combination of two exponential parts, one exponentially increasing and another exponentially decreasing. We find exact solutions of the Dirac equation with the field under consideration with appropriate asymptotic conditions and calculate all the characteristics of particle creation effect, in particular, differential mean numbers of created particle, total number of created particles, and the probability for a vacuum to remain a vacuum. Characteristic asymptotic regimes are discussed in detail and a comparison with the pure asymptotically decaying field is considered. (orig.)

  13. Modelling of new generation plasma optical devices

    Directory of Open Access Journals (Sweden)

    Litovko Irina V.

    2016-06-01

    Full Text Available The paper presents new generation plasma optical devices based on the electrostatic plasma lens configuration that opens a novel attractive possibility for effective high-tech practical applications. Original approaches to use of plasma accelerators with closed electron drift and open walls for the creation of a cost-effective low-maintenance plasma lens with positive space charge and possible application for low-cost, low-energy rocket engine are described. The preliminary experimental, theoretical and simulation results are presented. It is noted that the presented plasma devices are attractive for many different applications in the state-of-the-art vacuum-plasma processing.

  14. Bulk-bronzied graphites for plasma-facing components in ITER (International Thermonuclear Experimental Reactor)

    Energy Technology Data Exchange (ETDEWEB)

    Hirooka, Y.; Conn, R.W.; Doerner, R.; Khandagle, M. (California Univ., Los Angeles, CA (USA). Inst. of Plasma and Fusion Research); Causey, R.; Wilson, K. (Sandia National Labs., Livermore, CA (USA)); Croessmann, D.; Whitley, J. (Sandia National Labs., Albuquerque, NM (USA)); Holland, D.; Smolik, G. (Idaho National Engineering Lab., Idaho Falls, ID (USA)); Matsuda, T.; Sogabe, T. (Toyo Tanso Co. Ltd., O

    1990-06-01

    Newly developed bulk-boronized graphites and boronized C-C composites with a total boron concentration ranging from 1 wt % to 30 wt % have been evaluated as plasma-facing component materials for the International Thermonuclear Experimental Reactor (ITER). Bulk-boronized graphites have been bombarded with high-flux deuterium plasmas at temperatures between 200 and 1600{degree}C. Plasma interaction induced erosion of bulk-boronized graphites is observed to be a factor of 2--3 smaller than that of pyrolytic graphite, in regimes of physical sputtering, chemical sputtering and radiation enhanced sublimation. Postbombardment thermal desorption spectroscopy indicates that bulk-boronized graphites enhance recombinative desorption of deuterium, which leads to a suppression of the formation of deuterocarbon due to chemical sputtering. The tritium inventory in graphite has been found to decrease by an order of magnitude due to 10 wt % bulk-boronization at temperatures above 1000{degree}C. The critical heat flux to induce cracking for bulk-boronized graphites has been found to be essentially the same as that for non-boronized graphites. Also, 10 wt % bulk-boronization of graphite hinders air oxidation nearly completely at 800{degree}C and reduces the steam oxidation rate by a factor of 2--3 at around 1100 and 1350{degree}C. 38 refs., 5 figs.

  15. Behind the Evolution-Creation Science Controversy.

    Science.gov (United States)

    Parker, Franklin

    1982-01-01

    Historical background to Arkansas Act 590, mandating inclusion of creationism in public school curriculum, is given, including the history of antievolution bills, emergence of textbook watchers, and political issues in the law's passage. Suggestions are given for elementary and secondary teachers to become informed and active regarding…

  16. Public Funds and Local Biotechnology Firm Creation

    NARCIS (Netherlands)

    Kolympiris, C.; Kalaitzandonakes, N.; Miller, D.

    2014-01-01

    A long stream of academic literature has established that public funding towards research and development matters for economic growth because it relates to increases in innovation, productivity and the like. The impact of public funding on the creation of new firms has received less attention in thi

  17. Creation of Magnetic Monopoles in Classical Scattering

    CERN Document Server

    Vachaspati, Tanmay

    2016-01-01

    We consider the creation of 't Hooft-Polyakov magnetic monopoles by scattering classical wave packets of gauge fields. An example with eight clearly separated magnetic poles created with parity violating helical initial conditions is shown. No clear separation of topological charge is observed with corresponding parity symmetric initial conditions.

  18. Fabrics China Creation Show Hold in Shanghai

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ On August 5-6th.the 3rd Fabrics China Creation Show(one series events of Reach & Touch),organized by China National Textile & Apparel Council and National Textile Development Center,was held in Shanghai,aiming to providing textile producers and designers a platform to show their inspirations and creative ideas in fabric design.

  19. The balancing act of optimised value creation

    NARCIS (Netherlands)

    Sheombar, Anand; Smit, Jakobus; Silvius, Gilbert

    2009-01-01

    In BOP ventures the notion of “selling to the poor” has steadily been replaced by business approaches that suggest sustainable value creation. This has certain implications, in particular the development of strategies that serve triple bottom-line goals. These include economic, social and environmen

  20. ICT APPROPRIATION: A KNOWLEDGE CREATION PERSPECTIVE

    DEFF Research Database (Denmark)

    Akther, Farzana

    . The theoretical basis of my research is Activity Theory, as developed by the Finnish psychologist Engeström on the basis of the Russian development psychologists Vygotsky’s and Leontjev’s research. This learning approach I have combined with Nonaka and Takeuchi's theory of the dynamics of knowledge creation...

  1. Re-creation of Chinese Traditional Clothing

    Institute of Scientific and Technical Information of China (English)

    刘瑜; 张祖芳

    2003-01-01

    On the basis of analysis on both the typical characteristics of Chinese traditional clothing and trendy fashion on present market that is inspired from it,this paper illustrates several re-creation methods of Chinese traditional clothing.These suggestions would push this oriental traditional clothing to a new high in world fashion field and adopted by more and more common people.

  2. Using Informal Education through Music Video Creation

    Science.gov (United States)

    Cayari, Christopher

    2014-01-01

    Music video creation provides students a new way to express themselves and become better performers and consumers of media. This article provides a new perspective on Lucy Green's informal music pedagogy by enabling students to create music videos in music classrooms; thus, students are able to create music videos that informally develop…

  3. Reconstructing Professional Learning Community as Collective Creation

    Science.gov (United States)

    Allen, David

    2013-01-01

    The article presents a cross-domain inquiry into schoolwide professional learning community. It examines tensions in how professional learning community is conceptualized and how it is enacted in the processes of teacher groups. Drawing on a study of contemporary theatre arts practices, it proposes a model of collective creation that highlights…

  4. Modeling value creation with enterprise architecture

    NARCIS (Netherlands)

    Singh, Prince Mayurank; Jonkers, H.; Iacob, Maria Eugenia; van Sinderen, Marten J.

    2014-01-01

    Firms may not succeed in business if strategies are not properly implemented in practice. Every firm needs to know, represent and master its value creation logic, not only to stay in business but also to keep growing. This paper is about focusing on an important topic in the field of strategic

  5. The Money-Creation Model: Another Pedagogy.

    Science.gov (United States)

    Gamble, Ralph C., Jr.

    1991-01-01

    Describes graphical techniques to help explain the multiple creation of deposits that accompany lending in a fractional reserve banking system. Presents a model that emphasizes the banking system, the interaction of total permitted, required, and excess reserves and deposits. Argues that the approach simplifies information to examining a slope…

  6. Creatio in musica - Creation in Music

    DEFF Research Database (Denmark)

    Schwab, Heinrich Wilhelm

    2007-01-01

    Book abstract  The meaning of the noun 'creation', and the verb 'to create', range from the traditional theological idea of God creating ex nihilo to a more recent sense of the process of artistic conception. This collection of thirteen essays, written by scholars of music, literature, the visual...

  7. Creatio in musica - Creation in Music

    DEFF Research Database (Denmark)

    Schwab, Heinrich Wilhelm

    2007-01-01

    Book abstract  The meaning of the noun 'creation', and the verb 'to create', range from the traditional theological idea of God creating ex nihilo to a more recent sense of the process of artistic conception. This collection of thirteen essays, written by scholars of music, literature, the visual...

  8. Particle creation from the quantum stress tensor

    CERN Document Server

    Firouzjaee, Javad T

    2015-01-01

    Among the different methods to derive particle creation, finding the quantum stress tensor expectation value gives a covariant quantity which can be used for examining the back-reaction issue. However this tensor also includes vacuum polarization in a way that depends on the vacuum chosen. Here we review different aspects of particle creation by looking at energy conservation and at the quantum stress tensor. It will be shown that in the case of general spherically symmetric black holes that have a \\emph{dynamical horizon}, as occurs in a cosmological context, one cannot have pair creation on the horizon because this violates energy conservation. This confirms the results obtained in other ways in a previous paper [25]. Looking at the expectation value of the quantum stress tensor with three different definitions of the vacuum state, we study the nature of particle creation and vacuum polarization in black hole and cosmological models, and the associated stress energy tensors. We show that the thermal tempera...

  9. Dinosaurs on the Ark: The Creation Museum

    Science.gov (United States)

    Asma, Stephen T.

    2007-01-01

    In this article, the author describes the Creation Museum, founded by Ken A. Ham and designed as a rebuttal to the evolutionary view taken by other natural history museums. He discusses the socially conservative roots of the museum's exhibits, and presents Ham's answers to questions about the museum. The message of the museum is that the Bible is…

  10. Tending the tensions in co-creation

    DEFF Research Database (Denmark)

    Phillips, Louise Jane

    -creation as a process of mutual learning to be valued at least as much as the outcome AND the neoliberal instrumentalisation of creativity in the service of social innovation and economic growth. The papers build on the themes of Knowledge and Power in Collaborative Research: A Reflexive Approach (Phillips, Kristiansen...

  11. The Money-Creation Model: Another Pedagogy.

    Science.gov (United States)

    Gamble, Ralph C., Jr.

    1991-01-01

    Describes graphical techniques to help explain the multiple creation of deposits that accompany lending in a fractional reserve banking system. Presents a model that emphasizes the banking system, the interaction of total permitted, required, and excess reserves and deposits. Argues that the approach simplifies information to examining a slope…

  12. Distinctive Dynamic Capabilities for New Business Creation

    DEFF Research Database (Denmark)

    Rosenø, Axel; Enkel, Ellen; Mezger, Florian

    2013-01-01

    This study examines the distinctive dynamic capabilities for new business creation in established companies. We argue that these are very different from those for managing incremental innovation within a company's core business. We also propose that such capabilities are needed in both slow...

  13. Tending the tensions in co-creation

    DEFF Research Database (Denmark)

    Phillips, Professor MSO Louise; Nordentoft, Helle Merete; Pedersen, Lektor Christina Hee;

    2013-01-01

    -creation as a process of mutual learning to be valued at least as much as the outcome AND the neoliberal instrumentalisation of creativity in the service of social innovation and economic growth. The papers build on the themes of Knowledge and Power in Collaborative Research: A Reflexive Approach (Phillips, Kristiansen...

  14. "Scientific Creationism"--A New Inquisition Brewing?

    Science.gov (United States)

    Cloud, Preston

    1977-01-01

    In light of the recent revival of the creationism versus evolution issue, the author briefly summarizes both positions, defends evolution on the basis of fossils and rock ages, and refutes six creationist arguments against evolution. For journal availability, see SO 505 260. (AV)

  15. Battle Brewing Over Arkansas Creationism Law.

    Science.gov (United States)

    Baum, Rudy

    1981-01-01

    Reports recent proceedings regarding a new law enacted in early 1981 in Arkansas which requires schools that teach evolution to teach what the law calls "creation-science." Opposition to the law by the American Civil Liberties Union is discussed. (CS)

  16. Facilitating value co-creation in networks

    DEFF Research Database (Denmark)

    Rasmussen, Mette Apollo

    The dissertation investigates through two ethnographic case studies how value co-creation takes place in inter-organizational networks that have been facilitated by a municipality. The contribution of the study to business network research is the emphasis on development phases of networks and the...

  17. CAS course on Plasma Wake Acceleration

    CERN Multimedia

    CERN Accelerator School

    2015-01-01

    The CERN Accelerator School (CAS) recently organised a specialised course on Plasma Wake Acceleration, held at CERN, Geneva, Switzerland, from 23 to 29 November 2014.    Following a number of introductory lectures on laser and plasma physics, as well as an overview of conventional accelerators and their limitations, the course covered a large number of aspects of plasma wake acceleration schemes: the creation of plasma by high power lasers or particle beams, a description of the plasma creation process through simulations and the characteristics of the accelerated particle beams, including results of the latest achievements. Lectures on beam diagnostics, the applications of plasma accelerated beams, and topical seminars completed the programme.  The course was very successful, with 109 students of 26 nationalities attending; most participants coming from European counties, but also from the US, Israel, India, South Korea, Russia and Ukraine. Feedback from the participants was...

  18. From Business Administration to Business Creation: The Case of the Kalevala Global Business Creation School

    Directory of Open Access Journals (Sweden)

    Marko Seppä

    2012-06-01

    Full Text Available Are there any businesses left to administer? The question is of course rhetorical and aimed at underscoring how several societies are more severely in need of creators of new businesses than managers of established ones. And yet, nearly all universities only produce masters of business administration, at best. Apart from theoretical research about business creation, and the education of masters of such research, universities are generally not equipped to produce knowledge for business creation or to produce masters of business creation. This conceptual article calls for a new, complementary approach to research and education, around the theme of global business creation. Due to the limitations and restrictions related to the traditions and practices of the science of business administration, where the means justify the ends, a new exploratory field coined as the “Art of Business Creation,” where the end justifies the means, is being explored for some inspiration. For a concrete solution, the concept of a globally distributed, enterprise-centric, entrepreneurial-faculty-driven, open-innovation-based, and social-media-empowered university entity is depicted in this article. It is a new-generation private-public-partnership and “Living Lab 2.0” referred to as Kalevala Global Business Creation School. The conceptualization draws from observations and action research during the Global Venture Lab Finland experiment at the University of Jyväskylä from 2007 to 2011.

  19. Cosmological particle creation in the lab?

    CERN Document Server

    Schützhold, Ralf

    2012-01-01

    One of the most striking examples for the production of particles out of the quantum vacuum due to external conditions is cosmological particle creation, which is caused by the expansion or contraction of the Universe. Already in 1939, Schr\\"odinger understood that the cosmic evolution could lead to a mixing of positive and negative frequencies and that this "would mean production or annihilation of matter, merely by the expansion". Later this phenomenon was derived via more modern techniques of quantum field theory in curved space-times by Parker (who apparently was not aware of Schr\\"odinger's work) and subsequently has been studied in numerous publications. Even though cosmological particle creation typically occurs on extremely large length scales, it is one of the very few examples for such fundamental effects where we actually may have observational evidence: According to the inflationary model of cosmology, the seeds for the anisotropies in the cosmic microwave background (CMB) and basically all large ...

  20. [Creation and management of organizational knowledge].

    Science.gov (United States)

    Shinyashiki, Gilberto Tadeu; Trevizan, Maria Auxiliadora; Mendes, Isabel Amélia

    2003-01-01

    With a view to creating and establishing a sustainable position of competitive advantage, the best organizations are increasingly investing in the application of concepts such as learning, knowledge and competency. The organization's creation or acquisition of knowledge about its actions represents an intangible resource that is capable of conferring a competitive advantage upon them. This knowledge derives from interactions developed in learning processes that occur in the organizational environment. The more specific characteristics this knowledge demonstrates in relation to the organization, the more it will become the foundation of its core competencies and, consequently, an important strategic asset. This article emphasizes nurses' role in the process of knowledge management, placing them in the intersection between horizontal and vertical information levels as well as in the creation of a sustainable competitive advantage. Authors believe that this contribution may represent an opportunity for a reflection about its implications for the scenarious of health and nursing practices.

  1. Cosmological particle creation in conformal gravity

    Directory of Open Access Journals (Sweden)

    Berezin Victor

    2016-01-01

    Full Text Available We constructed the conformally invariant model for scalar particle creation induced by strong gravitational fields. Starting from the “usual” hydrodynamical description of the particle motion written in the Eulerian coordinates we substituted the particle number conservation law (which enters the formalism by “the particle creation law”, proportional to the square of the Weyl tensor (following the famous result by Ya. B. Zel‘dovich and A. A. Starobinsky. Then, demanding the conformal invariance of the whole dynamical system, we have got both the (Weyl-conformal gravity and the Einstein–Hilbert–dilaton gravity action integral. Thus, we obtained something like the induced gravity suggested first by A. D. Sakharov. It is shown that the resulting system is self-consistent. Some future developments of the theory are discussed in the concluding Chapter.

  2. Technological Creation Fuels Oil Giant's Development

    Institute of Scientific and Technical Information of China (English)

    Mu Zongyan

    2006-01-01

    @@ Sinopec has focused itself on development, conversion and extension of core technologies and specialized technologies in the recent years to fuel its main business development. With the efforts for IPR protection, Sinopec has achieved a series of technological creation results,which lead to huge social and economic benefits. Sinopec has also seen a significant change in the total amount,structure and quality of its assets thanks to those creation results. The sales income of Sinopec, for the first time,topped 800 billion yuan in 2005 with the profits and taxes exceeding 100 billion yuan. With the core competitiveness boosted continually, Sinopec rose to No.31 in the ranking of Fortune Global Top 500.

  3. The Creation and Destruction of Social Capital

    DEFF Research Database (Denmark)

    Svendsen, Gunnar Lind Haase; Svendsen, Gert Tinggaard

    ‘A welcome contribution to scholarly economic and public policy debates, The Creation and Destruction of Social Capital is written for advanced students yet offers insights critical to better understanding micro and macro economics alike.' - Willis M. Buhle, The Midwest Book Review ‘The Svendsens...... in to crafting this study.' - From the foreword by Elinor Ostrom Is social capital the ‘missing link' in economics? In this vital new book, the authors argue that the ‘forgotten' production factor of social capital is as crucial in economic decision-making as the other more traditional factors of production...... such as physical, financial and human capital. They attempt to bridge the gap between theory and reality by examining the main factors that determine entrepreneurship, co-operative movements and the creation and destruction of social capital....

  4. Making sense of Islamic creationism in Europe.

    Science.gov (United States)

    Hameed, Salman

    2015-05-01

    Islamic creationism has been noted as a serious concern in Europe. There have been reports of boycotts of university evolution lectures and, in one extreme case, even a threat of violence. While religious objections are indeed at play in some cases, our understanding of the rise of Islamic creationism should also take into account socioeconomic disparities and its impact on education for Muslim minorities in Europe. Furthermore, the broader narrative of rejection of evolution in Europe, for some Muslims, may be bound up in reactions to the secular culture and in the formation of their own minority religious identity. On the other hand, the stories of Muslim rejection of evolution in media end up reinforcing the stereotype of Muslims as "outsiders" and a threat to the European education system. A nuanced understanding of this dynamic may benefit those who support both the propagation of good science and favor cultural pluralism.

  5. Networks and knowledge creation for meaning

    DEFF Research Database (Denmark)

    Brink, Tove

    2016-01-01

    The research in this paper reveals how business networks can create organisational knowledge to provide meaning for enabling innovation and reduction of Levelized Cost Of Energy (LCOE)? The research was conducted from June 2014 to May 2015, using a qualitative deductive research approach...... the meaning necessary for innovation. In the organising process sources of systematic storage in the enterprise, education and training and the essential knowledge creation through people need to be emphasised on the creation of meaning for innovation and reduction of LCOE. Each of these sources is important...... and due to the organising process highly valuable findings regarding innovation can be utilised both for improved central decisions and for improved application of knowledge locally when the meaning is established. Further research is needed for elaboration of the business network frame and the organising...

  6. How spatial context influences entrepreneurial value creation

    DEFF Research Database (Denmark)

    Müller, Sabine

    2014-01-01

    This paper investigates how rural communities are enriched by entrepreneurial value-creating activities that go beyond job creation and growth. In addition, this study explores how spatial context influences these value-creating activities. This qualitative case-based study shows that rural......-being of the community. Thus, this study contributes to an in-depth understanding of how and why entrepreneurship can create multiple forms of value in rural areas as well as how value creation behaviours are motivated by the spatial context. In addition, it provides explanations why not all rural entrepreneurs...... contribute or at least intend to contribute equally and in a similar way to local development. Thus, by adding contextualized explanations of rural entrepreneurial behaviour to the literature, this study places itself in the recent debate and call for contextualizing entrepreneurship research....

  7. Particle creation phenomenology and conformal gravity

    CERN Document Server

    Berezin, Victor; Eroshenko, Yury

    2016-01-01

    We constructed the conformally invariant model for scalar particle creation induced by strong gravitational fields. Starting from the "usual" hydrodynamical description of the particle motion written in the Eulerian coordinates we substituted the particle number conservation law (which enters the formalism) by "the particle creation law", proportional to the square of the Weyl tensor (following the famous result by Ya. B. Zel`dovich and A. A.Starobinsky). Then, demanding the conformal invariance of the whole dynamical system, we have got both the (Weyl)-conformal gravity and the Einstein-Hilbert-dilaton gravity action integral. Thus, we obtained something like the induced gravity suggested first by A. D. Sakharov. It is shown that the resulting system is self-consistent. Some future developments of the theory are discussed in the Conclusion.

  8. The creation and circulation of public geographies

    OpenAIRE

    Kitchin, Rob; Linehan, Denis; O'Callaghan, Cian; Lawton, Philip

    2013-01-01

    In response to the commentaries, we discuss further how social media disrupts and remakes the creation and circulation of geographical knowledges and potentially reconfigures the moral economy of the social sciences. In particular, we examine questions of what is meant by public geography, the publics which such geographies serve, alternative and complementary approaches to social media, the politics of authorship within collective blogs, the politics and mechanisms of knowledge c...

  9. Logistics potentials in business competitive advantage creation

    OpenAIRE

    Rafał Matwiejczuk

    2013-01-01

    Background: Companies constantly search for ways to achieve and sustain long-term competitive advantage. Among the factors influencing the competitive advantage creation there are so called logistics potentials, which constitute a component part of a business strategic potentials. Logistics resources, logistics capabilities and logistics competences are the main components of the logistics potentials structure and hierarchy. Methods: In order to recognize the logistics potentials which de...

  10. Technological Opportunities and New Firm Creation

    OpenAIRE

    Scott Shane

    2001-01-01

    Research on the creation of new high-technology companies has typically focused either on industry-level factors such as market structure and technology regime or on individual-level factors such as the work experience of entrepreneurs. This study complements these approaches by examining the effect of technological opportunities on firm formation. In particular, the study shows that the probability that an invention will be commercialized through firm formation is influenced by its importanc...

  11. Chôra : Creation and Pathology

    DEFF Research Database (Denmark)

    Isar, Nicoletta

    2009-01-01

    Plato's dialogue the Timaeus describes not only the making of the cosmos (order), but also the condition of what is not order, neither for the human body nor for the universe. What is disorder in cosmogonic terms it is disease for the human body. Timaeus applies to the concept chôra in discussing....... http://www.ejop.org/archives/2009/05/chara_creation.html...

  12. Multi-pair states in electron-positron pair creation

    Science.gov (United States)

    Wöllert, Anton; Bauke, Heiko; Keitel, Christoph H.

    2016-09-01

    Ultra strong electromagnetic fields can lead to spontaneous creation of single or multiple electron-positron pairs. A quantum field theoretical treatment of the pair creation process combined with numerical methods provides a description of the fermionic quantum field state, from which all observables of the multiple electron-positron pairs can be inferred. This allows to study the complex multi-particle dynamics of electron-positron pair creation in-depth, including multi-pair statistics as well as momentum distributions and spin. To illustrate the potential benefit of this approach, it is applied to the intermediate regime of pair creation between nonperturbative Schwinger pair creation and perturbative multiphoton pair creation where the creation of multi-pair states becomes nonnegligible but cascades do not yet set in. Furthermore, it is demonstrated how spin and helicity of the created electrons and positrons are affected by the polarization of the counterpropagating laser fields, which induce the creation of electron-positron pairs.

  13. Role of Waste Management in Wealth Creation in Nigeria ...

    African Journals Online (AJOL)

    Role of Waste Management in Wealth Creation in Nigeria- Evidences From Lagos ... and how waste recycling affects the creation of small or large business ventures ... in the processes as this would help to create business for entrepreneurs.

  14. Particle creation rate for dynamical black holes

    Energy Technology Data Exchange (ETDEWEB)

    Firouzjaee, Javad T. [School of Astronomy, Institute for Research in Fundamental Sciences (IPM), Tehran (Iran, Islamic Republic of); University of Oxford, Department of Physics (Astrophysics), Oxford (United Kingdom); Ellis, George F.R. [University of Cape Town, Mathematics and Applied Mathematics Department, Rondebosch (South Africa)

    2016-11-15

    We present the particle creation probability rate around a general black hole as an outcome of quantum fluctuations. Using the uncertainty principle for these fluctuation, we derive a new ultraviolet frequency cutoff for the radiation spectrum of a dynamical black hole. Using this frequency cutoff, we define the probability creation rate function for such black holes. We consider a dynamical Vaidya model and calculate the probability creation rate for this case when its horizon is in a slowly evolving phase. Our results show that one can expect the usual Hawking radiation emission process in the case of a dynamical black hole when it has a slowly evolving horizon. Moreover, calculating the probability rate for a dynamical black hole gives a measure of when Hawking radiation can be killed off by an incoming flux of matter or radiation. Our result strictly suggests that we have to revise the Hawking radiation expectation for primordial black holes that have grown substantially since they were created in the early universe. We also infer that this frequency cut off can be a parameter that shows the primordial black hole growth at the emission moment. (orig.)

  15. Creation of Reversible Cholestatic Rat Model

    Science.gov (United States)

    Subhas, Gokulakkrishna

    2011-01-01

    Cholestasis is a clinical condition commonly encountered by both surgeons and gastroenterologists. Cholestasis can cause various physiological changes and affect the nutritional status and surgical outcomes. Study of the pathophysiological changes occurring in the liver and other organs is of importance. Various studies have been done in cholestatic rat models. We used a reversible cholestatic rat model in our recent study looking at the role of methylprednisolone in the ischemia reperfusion injury. Various techniques for creation of a reversible cholestatic model have been described. Creation of a reversible cholestatic rat model can be challenging in view of the smaller size and unique hepatopancreatobiliary anatomy in rats. This video article demonstrates the creation of a reversible cholestatic model. This model can be used in various studies, such as looking at the changes in nutritional, physiological, pathological, histological and immunological changes in the gastrointestinal tract. This model can also be used to see the effects of cholestasis and various therapeutic interventions on major hepatic surgeries. PMID:21633335

  16. Dockomatic - automated ligand creation and docking

    Directory of Open Access Journals (Sweden)

    Hampikian Greg

    2010-11-01

    Full Text Available Abstract Background The application of computational modeling to rationally design drugs and characterize macro biomolecular receptors has proven increasingly useful due to the accessibility of computing clusters and clouds. AutoDock is a well-known and powerful software program used to model ligand to receptor binding interactions. In its current version, AutoDock requires significant amounts of user time to setup and run jobs, and collect results. This paper presents DockoMatic, a user friendly Graphical User Interface (GUI application that eases and automates the creation and management of AutoDock jobs for high throughput screening of ligand to receptor interactions. Results DockoMatic allows the user to invoke and manage AutoDock jobs on a single computer or cluster, including jobs for evaluating secondary ligand interactions. It also automates the process of collecting, summarizing, and viewing results. In addition, DockoMatic automates creation of peptide ligand .pdb files from strings of single-letter amino acid abbreviations. Conclusions DockoMatic significantly reduces the complexity of managing multiple AutoDock jobs by facilitating ligand and AutoDock job creation and management.

  17. Dockomatic - automated ligand creation and docking.

    Science.gov (United States)

    Bullock, Casey W; Jacob, Reed B; McDougal, Owen M; Hampikian, Greg; Andersen, Tim

    2010-11-08

    The application of computational modeling to rationally design drugs and characterize macro biomolecular receptors has proven increasingly useful due to the accessibility of computing clusters and clouds. AutoDock is a well-known and powerful software program used to model ligand to receptor binding interactions. In its current version, AutoDock requires significant amounts of user time to setup and run jobs, and collect results. This paper presents DockoMatic, a user friendly Graphical User Interface (GUI) application that eases and automates the creation and management of AutoDock jobs for high throughput screening of ligand to receptor interactions. DockoMatic allows the user to invoke and manage AutoDock jobs on a single computer or cluster, including jobs for evaluating secondary ligand interactions. It also automates the process of collecting, summarizing, and viewing results. In addition, DockoMatic automates creation of peptide ligand .pdb files from strings of single-letter amino acid abbreviations. DockoMatic significantly reduces the complexity of managing multiple AutoDock jobs by facilitating ligand and AutoDock job creation and management.

  18. Particle creation rate for dynamical black holes

    Science.gov (United States)

    Firouzjaee, Javad T.; Ellis, George F. R.

    2016-11-01

    We present the particle creation probability rate around a general black hole as an outcome of quantum fluctuations. Using the uncertainty principle for these fluctuation, we derive a new ultraviolet frequency cutoff for the radiation spectrum of a dynamical black hole. Using this frequency cutoff, we define the probability creation rate function for such black holes. We consider a dynamical Vaidya model and calculate the probability creation rate for this case when its horizon is in a slowly evolving phase. Our results show that one can expect the usual Hawking radiation emission process in the case of a dynamical black hole when it has a slowly evolving horizon. Moreover, calculating the probability rate for a dynamical black hole gives a measure of when Hawking radiation can be killed off by an incoming flux of matter or radiation. Our result strictly suggests that we have to revise the Hawking radiation expectation for primordial black holes that have grown substantially since they were created in the early universe. We also infer that this frequency cut off can be a parameter that shows the primordial black hole growth at the emission moment.

  19. THE CREATION AND DEVELOPMENT OF JOB IN NIGERIA: ENTREPRENEURSHIP ENLIGHTENMENT

    OpenAIRE

    Money, Udih

    2016-01-01

    This paper is an opinion one that examined the significant role of entrepreneurship enlightenment in the creation and development of job in Nigeria. Entrepreneurship enlightenment that is continuous and reaching the citizens will help in the creation and development of job. It is viewed that entrepreneurship enlightenment is a giant stride towards creation and development of job in Nigeria. This paper also touches the challenges facing entrepreneurship development and job creation in Nigeria....

  20. The potential of shared value creation: a theoretical analysis

    OpenAIRE

    Victor Danciu

    2016-01-01

    The urgent issues economy, environment and society are facing need new approaches which allow a well-balanced sharing of value created by the economy. A step forward is the concept of shared value creation. This paper aims to analyze the main features, the content of strategy of shared value creation and to propose the social innovation as main strategic way of shared value creation. At the beginning, the drivers and challenges of shared value creation are investigated in a systematized manne...

  1. Creative participation: collective sentiment in online co-creation communities

    NARCIS (Netherlands)

    Lee, H.H.M.; van Dolen, W.

    2015-01-01

    Co-creation communities allow companies to utilize consumers’ creative thinking in the innovation process. This paper seeks to understand the role of sentiment in user co-creation. The results suggest that management style can affect the success of co-creation communities. Specific employees’ commun

  2. Creative participation: collective sentiment in online co-creation communities

    NARCIS (Netherlands)

    Lee, H.H.M.; van Dolen, W.

    2015-01-01

    Co-creation communities allow companies to utilize consumers’ creative thinking in the innovation process. This paper seeks to understand the role of sentiment in user co-creation. The results suggest that management style can affect the success of co-creation communities. Specific employees’

  3. Simulation of the target creation through FRC merging for a magneto-inertial fusion concept

    Science.gov (United States)

    Li, Chenguang; Yang, Xianjun

    2017-04-01

    A two-dimensional magnetohydrodynamics model has been used to simulate the target creation process in a magneto-inertial fusion concept named Magnetized Plasma Fusion Reactor (MPFR) [C. Li and X. Yang, Phys. Plasmas 23, 102702 (2016)], where the target plasma created through Field reversed configuration (FRC) merging was compressed by an imploding liner driven by the pulsed-power driver. In the scheme, two initial FRCs (Field reversed configurations) are translated into the region where FRC merging occurs, bringing out the target plasma ready for compression. The simulations cover the three stages of the target creation process: formation, translation, and merging. The factors affecting the achieved target are analyzed numerically. The magnetic field gradient produced by the conical coils is found to determine how fast the FRC is accelerated to peak velocity and the collision merging occurs. Moreover, it is demonstrated that FRC merging can be realized by real coils with gaps showing nearly identical performance, and the optimized target by FRC merging shows larger internal energy and retained flux, which is more suitable for the MPFR concept.

  4. The Creation Process in Digital Art

    Science.gov (United States)

    Marcos, Adérito Fernandes; Branco, Pedro Sérgio; Zagalo, Nelson Troca

    The process behind the act of the art creation or the creation process has been the subject of much debate and research during the last fifty years at least, even thinking art and beauty has been a subject of analysis already by the ancient Greeks such were Plato or Aristotle. Even though intuitively it is a simple phenomenon, creativity or the human ability to generate innovation (new ideas, concepts, etc.) is in fact quite complex. It has been studied from the perspectives of behavioral and social psychology, cognitive science, artificial intelligence, philosophy, history, design research, digital art, and computational aesthetics, among others. In spite of many years of discussion and research there is no single, authoritative perspective or definition of creativity, i.e., there is no standardized measurement technique. Regarding the development process that supports the intellectual act of creation it is usually described as a procedure where the artist experiments the medium, explores it with one or more techniques, changing shapes, forms, appearances, where beyond time and space, he/she seeks his/her way out to a clearing, i.e., envisages a path from intention to realization. Duchamp in his lecture "The Creative Act" states the artist is never alone with his/her artwork; there is always the spectator that later on will react critically to the work of art. If the artist succeeds in transmitting his/her intentions in terms of a message, emotion or feeling to the spectator then a form of aesthetic osmosis actually takes place through the inert matter (the medium) that enabled this communication or interaction phenomenon to occur. The role of the spectator may become gradually more active by interacting with the artwork itself possibly changing or becoming a part of it [2][4].

  5. Knowledge creation and transfer among postgraduate students

    Directory of Open Access Journals (Sweden)

    Kreeson Naicker

    2014-03-01

    Full Text Available Background: The skill shortages, hyper-competitive economic environments and untapped economies have created a great deal of focus on knowledge. Thus, continuously creating and transferring knowledge is critical for every organisation.Objectives: This article reports on an exploratory study undertaken to ascertain how knowledge is created and transferred amongst post-graduate (PG students, using the knowledge (socialisation, externalisation, combination, internalisation [SECI] spiral model.Method: After reviewing relevant literature, a personally administered standardised questionnaire was used to collect data from a convenience sample of PG students in the School of Management, IT and Governance at the University of KwaZulu-Natal, South Africa. The data was analysed to determine if it fit the model based on the four modes of knowledge conversion.Results: Although the School of Management, IT and Governance has mechanisms in place to facilitate knowledge creation and transfer, it nevertheless tends to focus on the four modes of knowledge conversion to varying degrees.Conclusion: The study confirmed that PG students utilise the ‘socialisation’ and ‘externalisation’ modes of knowledge conversion comprehensively; ‘internalisation’ plays a significant role in their knowledge creation and transfer activities and whilst ‘combination’ is utilised to a lesser extent, it still plays a role in PG students’ knowledge creation and transfer activities. PG students also have ‘space’ that allows them to bring hunches, thoughts, notions, intuition or tacit knowledge into reality. Trust and dedication are common amongst PG students. With socialisation and externalisation so high, PG students are aware of each other’s capabilities and competencies, and trust each other enough to share knowledge.

  6. Knowledge creation and transfer among postgraduate students

    Directory of Open Access Journals (Sweden)

    Kreeson Naicker

    2014-08-01

    Full Text Available Background: The skill shortages, hyper-competitive economic environments and untapped economies have created a great deal of focus on knowledge. Thus, continuously creating and transferring knowledge is critical for every organisation. Objectives: This article reports on an exploratory study undertaken to ascertain how knowledge is created and transferred amongst post-graduate (PG students, using the knowledge (socialisation, externalisation, combination, internalisation [SECI] spiral model. Method: After reviewing relevant literature, a personally administered standardised questionnaire was used to collect data from a convenience sample of PG students in the School of Management, IT and Governance at the University of KwaZulu-Natal, South Africa. The data was analysed to determine if it fit the model based on the four modes of knowledge conversion. Results: Although the School of Management, IT and Governance has mechanisms in place to facilitate knowledge creation and transfer, it nevertheless tends to focus on the four modes of knowledge conversion to varying degrees. Conclusion: The study confirmed that PG students utilise the ‘socialisation’ and ‘externalisation’ modes of knowledge conversion comprehensively; ‘internalisation’ plays a significant role in their knowledge creation and transfer activities and whilst ‘combination’ is utilised to a lesser extent, it still plays a role in PG students’ knowledge creation and transfer activities. PG students also have ‘space’ that allows them to bring hunches, thoughts, notions, intuition or tacit knowledge into reality. Trust and dedication are common amongst PG students. With socialisation and externalisation so high, PG students are aware of each other’s capabilities and competencies, and trust each other enough to share knowledge.

  7. Deposit Money Creation in Search Equilibrium

    OpenAIRE

    Keiichiro Kobayashi

    2002-01-01

    The endogenous creation of bank credit and of deposit money is modeled. If banks have a limited ability to commit to making interbank loans, then, in order for bank deposits to be accepted as liquid assets, an upper bound is placed upon the size of each bank's asset portfolio, where the bound is determined as a certain multiple of the bank's capital. In our search model, the Central Limit Theorem implies that the multiplier is a non-linear function of the aggregate level of bank assets. Thus ...

  8. Entrepreneurial Functionality Of New Venture Creation Learners

    Directory of Open Access Journals (Sweden)

    Philna Buys

    2006-11-01

    Full Text Available The primary objective of this study was to evaluate the suitability of individuals as potential entrepreneurs in the entrepreneurial economic environment. The scientifically validated Functional Intelligence Assessment Tool (FIAT was applied to nineteen individuals (learners during their training (New Venture Creation Learnership or NVC Learnership which was managed by the Services Sector Education and Training Authority (SETA. Only three of the nineteen respondents were found to be suitable as entrepreneurs of whom two also displayed leadership qualities. The implications of the findings are discussed.

  9. Haulier Value Creation in Supply Chains

    DEFF Research Database (Denmark)

    Borgström, Benedikte; Gammelgaard, Britta

    2017-01-01

    Purpose: Road transport is a dynamic sector with market changes because of liberalization and increasing demand of transport and logistics services. Shippers’ supply chain objectives of low costs and agility and a demanding operating environment due to, for example, congestion is challenging...... understanding of capability deployment. Original/value: This research shows that innovation of transport companies’ (hauliers’ and other types of logistics providers’) value propositions drives competitiveness. The strategy-as-practice approach is applied as the theoretical lens for understanding and developing...... strategic outcomes of transport and logistics provision and supply chain value creation....

  10. ZBrush Character Creation Advanced Digital Sculpting

    CERN Document Server

    Spencer, Scott

    2011-01-01

    A stunning, content-rich update to this top-selling ZBrush guide! This second edition of ZBrush Character Creation has been fully updated for ZBrush 4, the newest version of this fascinating and popular 3D sculpting software. ZBrush enables users to create detailed organic models using a brush-based toolset and tablet. The startling results look as though they've been painted with real brushes and oils, and ZBrush is increasingly popular for use in film, game, and broadcast pipelines. Author Scott Spencer is embedded in the ZBrush community and his movie credits include Harry Potter and The Or

  11. Called home: The creation of family life.

    Science.gov (United States)

    Hutch, R A

    1992-09-01

    Engendering family life is a spiritual process (theosis) based on human ethological constants of gender difference and generational turnover. Recent studies on ethnicity suggest that such a process retrieves a primordial sense of the human species as a whole, "humankind." Families, especially in this broad sense, link together the living and the dead and, at their best, morally empower individuals who link their destinies to such a vision of creation and human health. Reference is made to work on human strengths and speciation by Erik Erikson and to that on maternal thinking by Sara Ruddick. A political program by which an ideology of "familism" can be made is offered.

  12. Enacting entrepreneurship as social value creation

    DEFF Research Database (Denmark)

    Korsgaard, Steffen T.; Anderson, Alistair

    2011-01-01

    situated. Accordingly, this article examines the enactment of a socialized opportunity to explore the process of entrepreneurial growth. We find that a conceptualization of social value creation usefully develops our understanding and challenges the view that economic growth is the only relevant outcome...... of entrepreneurship. Our case study shows how social value is created in multiple forms at different centres and on different levels: from individual self-realization over community development to broad societal impact. We also find complex interrelations between the different levels and centres, thus, we argue...

  13. Money creation in the modern economy

    OpenAIRE

    McLeay, Michael; Radia, Amar; Thomas, Ryland

    2014-01-01

    This article explains how the majority of money in the modern economy is created by commercial banks making loans. Money creation in practice differs from some popular misconceptions — banks do not act simply as intermediaries, lending out deposits that savers place with them, and nor do they ‘multiply up’ central bank money to create new loans and deposits. The amount of money created in the economy ultimately depends on the monetary policy of the central bank. In normal times, this is carri...

  14. Pair creation in noncommutative space-time

    Science.gov (United States)

    Hamil, B.; Chetouani, L.

    2016-09-01

    By taking two interactions, the Volkov plane wave and a constant electromagnetic field, the probability related to the process of pair creation from the vacuum is exactly and analytically determined via the Schwinger method in noncommutative space-time. For the plane wave, it is shown that the probability is simply null and for the electromagnetic wave it is found that the expression of the probability has a similar form to that obtained by Schwinger in a commutative space-time. For a certain critical value of H, the probability is simply equal to 1.

  15. Creation of an antiferromagnetic exchange spring

    Energy Technology Data Exchange (ETDEWEB)

    Scholl, A.; Liberati, M.; Arenholz, E.; Ohldag, H.; Stohr, J.

    2004-04-06

    We present evidence for the creation of an exchange spring in an antiferromagnet due to exchange coupling to a ferromagnet. X-ray magnetic linear dichroism spectroscopy on single crystal Co/NiO(001) shows that a partial domain wall is wound up at the surface of the antiferromagnet when the adjacent ferromagnet is rotated by a magnetic field. We determine the interface exchange stiffness and the antiferromagnetic domain wall energy from the field dependence of the direction of the antiferromagnetic axis, the antiferromagnetic pendant to a ferromagnetic hysteresis loop. The existence of a planar antiferromagnetic domain wall, proven by our measurement, is a key assumption of most exchange bias models.

  16. Rents in property rights creation and implementation

    Directory of Open Access Journals (Sweden)

    Žarković Jelena

    2006-01-01

    Full Text Available The institution of property rights is increasingly being recognized as an essential building block of an economically prosperous society. The question that remains unanswered however, is how do we develop effective property rights institutions? The literature dealing with the development of property rights tends to be, in general, overly optimistic since there is a tendency to view the design of property rights institutions as optimizing decisions to economize on transaction costs and to facilitate new economic activities. On the other hand, since property rights define the distribution of wealth and political power in a society changes in property rights structures are likely to be influenced by more than pure efficiency considerations. Therefore, in order to achieve a balanced analysis of the evolution of property rights institutions our article introduces the state in the whole process. Following the propositions of the interest group theory of government we show an important relationship between rent seeking and state involvement in property rights creation. The state with a coercive power to establish and enforce property rights can also use that power, through the process of economic regulation, to redistribute property rights to politically influential interest groups. Herein lies the state failure in property rights creation.

  17. ARTISTIC AND SCIENTIFIC CREATION PROCESS MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Ioan Tudor

    2013-12-01

    Full Text Available Cultural creation is not ex nihilo, but a conversion of old “material” into a new form or a re-signifying, or a new combination of preexisting elements. Art, as well as science, has been characterized as acts of dominating and transforming nature. In art, the process is real and in science it is virtual. This process is characterized by an efficient management of the means of expression which must be subordinated to the message that the piece of art wants to transmit and the scientist exploits facts in order to make them significant as support, expression and exemplification of the laws of nature. There is also an ontogenesis of management: individual evolution which takes place by virtue of a program, thanks to devices with self-regulating capabilities. This aspect may be particularly interesting for cyberneticists. In contemporary civilization the transfer of certain aspects of the creation process to automated machines implies programming, algorithms. Man is an algorithmic being.

  18. WORD CREATION PRACTICE OF GENRIKH SAPGIR

    Directory of Open Access Journals (Sweden)

    Yu. B. Orlitskiy

    2016-01-01

    Full Text Available Genrikh Sapgir’s (1928–1999 word creation manifested in two dozen of his conceptual books of 1960-1990-ies can be considered a direct continuation and further development of similar practices by Velimir Khlebnikov, described in detail in the works by R. Vroon, V. Grigor’ev and N. Pertsova, to which the author refers. The two poets are similar in the sets of the most productive patterns of word formation and in overall density of the neological layer in poems of different genres and forms. On the other hand, as compared with Khlebnikov, Sapgir more often goes beyond the Slavic and «Eastern» vocabulary, more extensively uses compounding, onomatopoeia, than his great predecessor; combines the classic stanza forms with neologisms, uses variative repetitions in one text and within cycles and books. Of particular interest are the so-called «half-word» actively used by Sapgir in different periods of his work and created, evidently, under the influence of futuristic language practice. Close to them are inversive words created by replacement of word parts, as well as macaronicisms which can also be considered as part of the general word creative field of the poet. All of this makes Sapgir heir to the futuristic practice of word creation

  19. Creationism and science: An impossible union?

    Science.gov (United States)

    Mims, Forrest M., III

    Eos reported on June 28, 1994, that the AGU Council has reaffirmed for the second time a statement on “Creationism” first adopted in December 1981. The brief statement opposes “…all efforts to require or promote the teaching of creationism or any other religious tenets as science.” The statement offers no definition of creationism.The AGU Council's rejection of “creationism” and “religious tenets as science” may be fashionable by today's standards but the rejection of any role for God in science is a comparatively recent development. Many great scientists of the past believed in and even wrote about their faith in a creator God. I know many scientists today who believe in God. Several years ago I lost an assignment to write a column for Scientific American after the editor learned that I am an evangelical Christian who rejects abortion and much of Darwinism. After my dismissal received widespread publicity in the national media, I received calls and letters of support from scientists in many fields, including medicine, biology, and paleontology, who believe as I do.

  20. All new custom path photo book creation

    Science.gov (United States)

    Wang, Wiley; Muzzolini, Russ

    2012-03-01

    In this paper, we present an all new custom path to allow consumers to have full control to their photos and the format of their books, while providing them with guidance to make their creation fast and easy. The users can choose to fully automate the initial creation, and then customize every page. The system manage many design themes along with numerous design elements, such as layouts, backgrounds, embellishments and pattern bands. The users can also utilize photos from multiple sources including their computers, Shutterfly accounts, Shutterfly Share sites and Facebook. The users can also use a photo as background, add, move and resize photos and text - putting what they want where they want instead of being confined to templates. The new path allows users to add embellishments anywhere in the book, and the high-performance platform can support up to 1,000 photos per book and up to 25 pictures per page. The path offers either Smart Autofill or Storyboard features allowing customers to populate their books with photos so they can add captions and customize the pages.

  1. Croatian Cartographic Data Model, Creation and Implementation

    Directory of Open Access Journals (Sweden)

    Zvonko Biljecki

    2003-09-01

    Full Text Available Croatian project Cartographic Data Model (KMP has been started as a component of the STOKIS (SGA, 1995, Official Topographic and Cartographic Information System project. The cartographic data model conforms to CROTIS (Topographic Information System of the Republic of Croatia. It enables the generation of the cartographic database from topographic one. Classification of data is performed by logical grouping of objects and depends on geometry, type and properties of features. The cartographic data model describes structure of cartographic database and all attributes, categories, types and fields. Description of geometry and exchange of data is performed according to the specification of ISO Standards, adapted by Technical Committee ISO/TC 211, Geographic information/Geomatics and OpenGIS Consortium. Creation of the cartographic data model is the basis for the creation of cartographic database. The next step is direct implementation of vector model that contains graphic and alphanumeric elements. The cartographic key must stay identical to TK25 and maps of other scales.

  2. Man creation had began since the creation of the first biological ...

    African Journals Online (AJOL)

    and new complementary insights for showing how montmorillonite clay could be the ... lead, since the beginning, to the emergence of a primitive genetic code. Page 2. 50. Keywords – Man creation, Early life evolution, Montmorillonite clay, RNA .... as important elements in the control of gene expression (Nahvi et al. 2002 ...

  3. Digital History: Problem of Creation of Resources

    Science.gov (United States)

    Uhlír, Zdenêk

    This paper is based on the reference background of historical librarianship, so that it does not address astronomical problems per se. In this respect we can see the historical astronomical material at three different levels: first, as factual data preserved from the past or as that we can take today as factual data; second, as evidence of the acquisition and explication of this factual material, i.e. history of astronomy as science; and third, as the inclusion of astronomical progress into historical material in general, and, in another sense, into the development of intellectual thought. At present we are witnessing a transition from an environment of predominantly printed material into an electronic-digital environment. In connection with this important change in communication there is also a new conceptualization of information and knowledge. This must be responded to by a conversion of existing sources and the creation of new ones. This wider horizon will require fundamental changes in the domain of the historical librarian. Creation of historical resources in the electronic-digital environment has three aspects: first, it is a permanent creation of digital image copies; second, building a catalogue as an access point common for both original and subsidiary documents; third, production of full-text databases of bibliographic and factual databases as well as comments-monographs. Owing to the fact that there does not exist in the electronic-digital environment any document in the strict sense of the word, it increases the importance of the context of data and the information itself becomes an interpretation. Also, due to the fact that the subject itself appears as a theme at more than one level, the knowledge becomes an interpretation at each next level. Thus the resources in the electronic-digital environment have the potential for an indirect, indefinite utilization. So it is not enough to just represent data in an objective way, but it is also necessary to

  4. Value Creation in Digital Application Marketplaces: A Developers’ Perspective

    DEFF Research Database (Denmark)

    Ghazawneh, Ahmad; Mansour, Osama

    2015-01-01

    Digital application marketplaces are increasingly relevant for digital platform owners seeking to reap the benefits of distributing, brokering, and operating applications by third-party developers. Owners of such marketplaces have two vital goals: address the needs of heterogeneous end-users and ...... sources and their associated value creation and realization. In doing this, our research extends and complements existing digital platform literature and contributes new knowledge about new forms of value creation.......-users and attract third-party developers. A key element in simultaneously accommodating these goals is value creation. However, while there is emerging literature on digital application marketplaces, little empirical evidence exits about the value creation process for and by application developers. Drawing...... on a research study of third-party developers, we synthesize the value creation perspective and digital platforms literature to develop an understanding of value creation in digital application marketplaces from the perspective of third-party developers. Our study identifies and explores six different value...

  5. "Origin," "creation," and "origin of life" some conceptual considerations.

    Science.gov (United States)

    Charpa, Ulrich

    2012-01-01

    This paper opens by drawing attention to the fact that there is some conceptual confusion with regard to "origin" and "creation." This has its historical roots in the beginnings of modern science and undoubtedly affects our positioning towards the evolutionism/creationism-debate. This article argues that there are relevant ontological, epistemological, thematic, methodological, and logical differences between "origin" and "creation." As a result, the analysis suggests keeping the usage of both concepts strictly quite separate. Creation is not simply another word for origin nor does it stand for an (from a rigid scientific point of view) awkward example of an origin. Irrespective of the apparent similarities as explanatory factors, origin and creation belong to fundamentally different types of concepts. Consequently, "origin of life" and those scientific projects connected to it present themselves as something distinct that neither competes nor meshes with thinking about creation.

  6. From Creativity to New Venture Creation

    DEFF Research Database (Denmark)

    Lund, Morten; Byrge, Christian; Nielsen, Christian

    2017-01-01

    , are discussed, followed by a more in-depth discussion of the interrelationships between the creative process and the business modeling process. The implications of the paper are discussed in terms of a combined study module aimed at new venture creation students and pupils within higher education as well......This paper explores the processes of creating new companies with original and useful business models from a conceptual perspective. Based on data from large-scale creativity training programs and business model development studies in Denmark encompassing over 100 companies and 200 entrepreneurs......, the key proposition of the paper is that entrepreneurs can enhance their development processes through training of their competences in creativity and in business modeling. The paper presents a set of key skill variables of creativity and of business modeling that need to be trained in order to enhance...

  7. Disruption, beamstrahlung, and beamstrahlung pair creation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, P.

    1988-12-01

    The two major effects from the interaction of e/sup /minus//e/sup +/ beams---beamstrahlung and disruption---are reviewed, with emphasis on flat beam collisions. For the disruption effects we discuss the luminosity enhancement factor, the maximum and rms disruption angles, and the ''kink instability''. All the results are obtained from computer simulations, and scaling laws based on these are deduced whenever possible. For the beamstrahlung effects, we concentrate only on the final electron energy spectrum and the deflection angle associated with low energy particles. In addition to the generic studies on the beam-beam effects, we also list the relevant beam-beam parameters obtained from simulations on two sample designs: the TLC and the ILC. As an addendum, the newly discovered phenomenon of coherent beamstrahlung pair creation, together with the incoherent process, are discussed. 18 refs., 15 figs., 1 tab.

  8. Entanglement creation in low-energy scattering

    Energy Technology Data Exchange (ETDEWEB)

    Weder, Ricardo [Institut National de Recherche en Informatique et en Automatique Paris-Rocquencourt, Projet POEMS, Domaine de Voluceau-Rocquencourt, BP 105, F-78153, Le Chesnay Cedex (France)

    2011-12-15

    We study the entanglement creation in the low-energy scattering of two particles in three dimensions, for a general class of interaction potentials that are not required to be spherically symmetric. The incoming asymptotic state, before the collision, is a product of two normalized Gaussian states. After the scattering, the particles are entangled. We take as a measure of the entanglement the purity of one of them. We provide a rigorous explicit computation, with error bound, of the leading order of the purity at low energy. The entanglement depends strongly on the difference of the masses. It takes its minimum when the masses are equal, and it increases rapidly with the difference of the masses. It is quite remarkable that the anisotropy of the potential gives no contribution to the leading order of the purity, in spite of the fact that entanglement is a second-order effect.

  9. The Creation and Destruction of Social Capital

    DEFF Research Database (Denmark)

    Svendsen, Gunnar Lind Haase; Svendsen, Gert Tinggaard

    ‘A welcome contribution to scholarly economic and public policy debates, The Creation and Destruction of Social Capital is written for advanced students yet offers insights critical to better understanding micro and macro economics alike.' - Willis M. Buhle, The Midwest Book Review ‘The Svendsens...... in public policies. . . This is the type of book that should be assigned to graduate students across the social sciences as an illustration of the kind of work that they should aspire to do. I know I have learned a great deal from reading this book and appreciate the effort that the Svendsens have put...... in to crafting this study.' - From the foreword by Elinor Ostrom Is social capital the ‘missing link' in economics? In this vital new book, the authors argue that the ‘forgotten' production factor of social capital is as crucial in economic decision-making as the other more traditional factors of production...

  10. Co-Creation in Higher Education

    DEFF Research Database (Denmark)

    The main purpose of this book is to disseminate new research on co-creative approaches to teaching and learning in Higher Education (HE). The cases presented draw from a Danish cultural and educational context and have a special focus on collaborative, co-creative and distributed perspectives......-led learning, arts-based approaches to higher educational research and teaching, collaborative practices. We believe that these perspectives are still in need of further investigation through theories and practices. We understand co-creation as the process of creative, original and valuable generation...... of shared meaning and development. This collected volume offers novel empirical documentation and original theoretical reflections on the application of co-creative processes in higher education. This can be directly relevant for educators and the ways in which they design education, but also for students...

  11. Collaborative Creation of a Lab Rubric

    Directory of Open Access Journals (Sweden)

    Carrie Miller-DeBoer

    2011-03-01

    Full Text Available While there are a number of tested rubrics in circulation, our task was to intervene in a particular situation: the lead professor was concerned because her graduate teaching assistants held negative views about student performance on the lab reports. GTAs found poor products frustrating, and admitted that their grading was thus superficial and provided no feedback to students. Specifically, GTAs did not feel equipped to evaluate writing and, as a result, simply graded on steps completed in the lab process.We have a rubric now for an Introduction to Zoology lab that could be submitted here as a pretty darn good rubric for other instructors to use. But the intent of our “Tips and Tools” is to describe the actual creation of the rubric. We believe the active “real time” development of the rubric carried as much or more value than the finished product.

  12. On new industry creation and legitimation

    DEFF Research Database (Denmark)

    Turcan, Romeo V.; Fraser, Norman

    The purpose of this paper is to discuss the process of creation and legitimation of new industries. Specifically, the question we address is how to cross the gulf between no industry and embryonic industry in order for a new industry to emerge. In this, our focus is on the process of change from...... an initial condition in which an industry does not exist to a final condition in which it is institutionalized. We ground our discussion in a typology of legitimation. Both authors bring to the discussion their ethnographic experience in creating and legitimating new industries and new ventures...... such as software, consulting and NGO, as well as de-legitimating existing industries, such as military and power. The contribution of this paper lies in its combined theoretical and practical focus on a phenomenon that has received scant attention in academic research and has been inefficiently practiced by policy...

  13. Autonomous Rule Creation for Intrusion Detection

    Energy Technology Data Exchange (ETDEWEB)

    Todd Vollmer; Jim Alves-Foss; Milos Manic

    2011-04-01

    Many computational intelligence techniques for anomaly based network intrusion detection can be found in literature. Translating a newly discovered intrusion recognition criteria into a distributable rule can be a human intensive effort. This paper explores a multi-modal genetic algorithm solution for autonomous rule creation. This algorithm focuses on the process of creating rules once an intrusion has been identified, rather than the evolution of rules to provide a solution for intrusion detection. The algorithm was demonstrated on anomalous ICMP network packets (input) and Snort rules (output of the algorithm). Output rules were sorted according to a fitness value and any duplicates were removed. The experimental results on ten test cases demonstrated a 100 percent rule alert rate. Out of 33,804 test packets 3 produced false positives. Each test case produced a minimum of three rule variations that could be used as candidates for a production system.

  14. Autonomous Rule Creation for Intrusion Detection

    Energy Technology Data Exchange (ETDEWEB)

    Todd Vollmer; Jim Alves-Foss; Milos Manic

    2011-04-01

    Many computational intelligence techniques for anomaly based network intrusion detection can be found in literature. Translating a newly discovered intrusion recognition criteria into a distributable rule can be a human intensive effort. This paper explores a multi-modal genetic algorithm solution for autonomous rule creation. This algorithm focuses on the process of creating rules once an intrusion has been identified, rather than the evolution of rules to provide a solution for intrusion detection. The algorithm was demonstrated on anomalous ICMP network packets (input) and Snort rules (output of the algorithm). Output rules were sorted according to a fitness value and any duplicates were removed. The experimental results on ten test cases demonstrated a 100 percent rule alert rate. Out of 33,804 test packets 3 produced false positives. Each test case produced a minimum of three rule variations that could be used as candidates for a production system.

  15. Explaining money creation by commercial banks

    DEFF Research Database (Denmark)

    Ravn, Ib

    2015-01-01

    Educators and economists concerned with monetary reform face the extraordinary challenge of explaining to the public and its elected representatives not only what a reformed system would look like, but also how the current system works. Centrally, the point that in a modern economy money is largely...... created by commercial banks, as explained by the Bank of England recently (McLeay, Radia & Thomas, 2014b), is often met with incredulity: “What do you mean, created?” This paper introduces five easy-to-grasp analogies that educators and reformers may use to convey key money-creation concepts to a lay...... audience. The analogies offered include (1) money as patches in an expandable patchwork quilt that covers a nation’s real assets, (2) the money supply as water in a bathtub with a faucet and a drain, (3) money understood as debt in a model economy run by schoolchildren, (4) the misleading concept of a bank...

  16. Explaining money creation by commercial banks

    DEFF Research Database (Denmark)

    Ravn, Ib

    2015-01-01

    Educators and economists concerned with monetary reform face the extraordinary challenge of explaining to the public and its elected representatives not only what a reformed system would look like, but also how the current system works. Centrally, the point that in a modern economy money is largely...... created by commercial banks, as explained by the Bank of England recently (McLeay, Radia & Thomas, 2014b), is often met with incredulity: “What do you mean, created?” This paper introduces five easy-to-grasp analogies that educators and reformers may use to convey key money-creation concepts to a lay...... audience. The analogies offered include (1) money as patches in an expandable patchwork quilt that covers a nation’s real assets, (2) the money supply as water in a bathtub with a faucet and a drain, (3) money understood as debt in a model economy run by schoolchildren, (4) the misleading concept of a bank...

  17. Origins the scientific story of creation

    CERN Document Server

    Baggott, Jim

    2015-01-01

    What is the nature of the material world? How does it work? What is the universe and how was it formed? What is life? Where do we come from and how did we evolve? How and why do we think? What does it mean to be human? How do we know? There are many different versions of our creation story. This book tells the version according to modern science. It is a unique account, starting at the Big Bang and travelling right up to the emergence of humans as conscious intelligent beings, 13.8 billion years later. Chapter by chapter, it sets out the current state of scientific knowledge: the origins of space and time; energy, mass, and light; galaxies, stars, and our sun; the habitable earth, and complex life itself. Drawing together the physical and biological sciences, Baggott recounts what we currently know of our history, highlighting the questions science has yet to answer.

  18. Service Creation and Deployment in Converged Networks

    DEFF Research Database (Denmark)

    Soler, José

    This monograph (Early Experiences related to Service Creation & Deployment in Converged Networks) presents different experiences related to architectures and mechanisms for deployment of telephony services, understood as especial features complementing the basic voice service. The context...... for these experiences is the transition of telecommunication (telephony) networks from circuit switched based systems towards packet based ones. The text of this monograph proceeds, unaltered for the most, from the author’s PhD thesis “Framework for Deployment of Advanced Telecommunication Services in Current...... and Future Converged Networks”, carried out at the Technical University of Denmark in the period [April 2002-April 2005]. Even though the technologies presented in the text have evolved from that period until now, the presented scenarios and setups are still valid as interesting initial steps in the realm....

  19. Automated Agent Ontology Creation for Distributed Databases

    Science.gov (United States)

    2004-03-01

    Query Agent ..……………………………………………………47 3.3 Database Agent Implementation…………………………………………………..48 3.3.1 Leader Election Procedure...algorithm. Section 3.3.1 details the leader election process, Section 3.3.2 discusses the Jaro method, and Section 3.3.3 details the ontology creation...Receives new number Receives new number from Agent2 from Agent2 Figure 3-2. Agent leader communication 49 3.3.1 Leader Election Procedure Figure

  20. libprofit: Image creation from luminosity profiles

    Science.gov (United States)

    Robotham, A. S. G.; Taranu, D.; Tobar, R.

    2016-12-01

    libprofit is a C++ library for image creation based on different luminosity profiles. It offers fast and accurate two-dimensional integration for a useful number of profiles, including Sersic, Core-Sersic, broken-exponential, Ferrer, Moffat, empirical King, point-source and sky, with a simple mechanism for adding new profiles. libprofit provides a utility to read the model and profile parameters from the command-line and generate the corresponding image. It can output the resulting image as text values, a binary stream, or as a simple FITS file. It also provides a shared library exposing an API that can be used by any third-party application. R and Python interfaces are available: ProFit (ascl:1612.004) and PyProfit (ascl:1612.005).

  1. Clinical Note Creation, Binning, and Artificial Intelligence.

    Science.gov (United States)

    Deliberato, Rodrigo Octávio; Celi, Leo Anthony; Stone, David J

    2017-08-03

    The creation of medical notes in software applications poses an intrinsic problem in workflow as the technology inherently intervenes in the processes of collecting and assembling information, as well as the production of a data-driven note that meets both individual and healthcare system requirements. In addition, the note writing applications in currently available electronic health records (EHRs) do not function to support decision making to any substantial degree. We suggest that artificial intelligence (AI) could be utilized to facilitate the workflows of the data collection and assembly processes, as well as to support the development of personalized, yet data-driven assessments and plans. ©Rodrigo Octávio Deliberato, Leo Anthony Celi, David J Stone. Originally published in JMIR Medical Informatics (http://medinform.jmir.org), 03.08.2017.

  2. OPTICAL DEFLECTOR CREATION FOR LASER THERAPEUTIC DEVICES

    Directory of Open Access Journals (Sweden)

    V. N. Baranov

    2014-03-01

    Full Text Available The paper deals with creation of optical deflector for management of laser radiation in physiotherapeutic devices. Design features and operation principles of electro-optical, optical-acoustic and mechanical deflectors, giving the possibility to carry out continuous or discrete scanning of a laser beam are shown. Operation mechanism of the mechanical type deflector on the example of domestic laser therapeutic scanners is described in detail. Application possibility in clinical practice for heating technique of the acupuncture points by volumetric scanning of tissues by the radiation of semiconductor lasers on wave lengths equal to 0,67 and 0,85 μm is investigated. Creation justification of the new type deflector is given. Comparison between stable and labile techniques of radiation is carried out. It is shown that more intensive warming up of a skin surface in acupuncture point projection is observed at volumetric scanning, rather than at planar scanning by laser beams. Temperature increase on a skin surface in projection of acupuncture points is detected at radiation in both the visible spectrum range (0,67 μm and the infrared range (0,85 μm. It gives the possibility to apply this scanning method to thermal photo-activation of the point and to extend an existing arsenal of laser reflexology methods. The optical deflector is offered for medical industry, making it possible to carry out volumetric scanning of a laser beam and to facilitate the medical personnel’s work in laser therapy and reflexology consulting rooms.

  3. Perspectives on the Logos’ immanence in Creation

    Directory of Open Access Journals (Sweden)

    Nicolae Moșoiu

    2016-03-01

    Full Text Available „The reasons of things that God prepared in advance for ages, as He Himself knew, can be seen through understanding from the creatures. For every creature of God, contemplated by us through nature, using science and knowledge, proclaim in a hidden manner the reasons after which they were made and they reveal the purpose placed by God in every creature. From the wise contemplation of creation we can perceive the Reason which enlightens us about the Holy Trinity, i.e. the Father, the Son and the Holy Spirit” [1]. Abstract: The article deals with the theme of the Logos` immanence in the creation. The first part includes a scientific perspective while the second, a theological one. The first evidence that the universe has a beginning dates back to the 20s of last century. Most scientists believed until then that the universe was stationary and had always existed; there are references to the big bang, string theory, M theory. The second part encompasses a perspective on the theme of the rational nature of the world which constitutes a firm foundation for dialogue between Theology and science. The logoi have a particularizing or a unifing function, and the complete unity of the logoi is realized through and by the Logos, the Word of God. The essential difference between paradigms and logoi is that the latter belong to the temporal level and to the empirical world, while the former preexist synthetically into God.The uncreated divine energies are the logoi in the action of creating and supporting of the beings.

  4. Creation of design by territorial branding

    OpenAIRE

    Вовк, А. В.; Некрасова, Н. Н.; Романишена, И. В.

    2014-01-01

    В работе исследован процесс создания территориального бренда, сформулированы основные стадии его разработки. Выделены ключевые направления, которые служат источником идей, при формировании бренда и создании целостной картинки восприятия брендируемой территории. Creation processes of a territorial brand is investigated in work, the basic stages of its working out are formulated. Key directions which are source for ideas of brand formation and creation of complete picture of perception terri...

  5. Creationism in the Grand Canyon, Texas Textbooks

    Science.gov (United States)

    Folger, Peter

    2004-01-01

    AGU President Bob Dickinson, together with presidents of six other scientific societies, have written to Joseph Alston, Superintendent of Grand Canyon National Park, pointing out that a creationist book, The Grand Canyon: A Different View, is being sold in bookstores within the borders of the park as a scientific explanation about Grand Canyon geologic history. President Dickinson's 16 December letter urges that Alston clearly separate The Grand Canyon: A Different View from books and materials that discuss the legitimate scientific understanding of the origin of the Grand Canyon. The letter warns the Park Service against giving the impression that it approves of the anti-science movement known as young-Earth creationism, or that it endorses the advancement of religious tenets disguised as science. The text of the letter is on AGU's Web site http://www.agu.org/sci_soc/policy/sci_pol.html. Also, this fall, AGU sent an alert to Texas members about efforts by intelligent design creationists aimed at weakening the teaching of biological evolution in textbooks used in Texas schools. The alert pointed scientists to a letter, drafted by AGU, together with the American Institute of Physics, the American Physical Society, the Optical Society of America, and the American Astronomical Society, that urged the Texas State Board of Education to adopt textbooks that presented only accepted, peer-reviewed science and pedagogical expertise. Over 550 scientists in Texas added their names to the letter (http://www.agu.org/sci_soc/policy/texas_textbooks.pdf ), sent to the Board of Education on 1 November prior to their vote to adopt a slate of new science textbooks. The Board voted 11-5 in favor of keeping the textbooks free of changes advocated by groups supporting intelligent design creationism.

  6. Money creation process in a random redistribution model

    Science.gov (United States)

    Chen, Siyan; Wang, Yougui; Li, Keqiang; Wu, Jinshan

    2014-01-01

    In this paper, the dynamical process of money creation in a random exchange model with debt is investigated. The money creation kinetics are analyzed by both the money-transfer matrix method and the diffusion method. From both approaches, we attain the same conclusion: the source of money creation in the case of random exchange is the agents with neither money nor debt. These analytical results are demonstrated by computer simulations.

  7. Knowledge-creation in student software-development teams

    Directory of Open Access Journals (Sweden)

    Mzwandile M. Shongwe

    2015-02-01

    Full Text Available Background: Knowledge-creation is a field of study that has gained popularity in recent times.Knowledge-creation is the creation of new ideas or new innovations. In computing, software development is regarded as knowledge-creation. This is because software-development involves the creation of a new innovation (software. Knowledge-creation studies in this field tend to focus mainly on knowledge-creation activities in business organisations. They use experienced, professional software-development teams as subjects, largely ignoring novice student development teams. This has denied the field of computing valuable knowledge about how novice teams create knowledge.Objectives: The study addressed this gap in the literature by investigating knowledge-creation in student software teams.Method: An ethnographic study was conducted on six student teams developing software in a management-information systems (MIS course. They were conducting a systems development project at a university during a term of study. Data were collected over a period of four months through participant observation and interviews.Results: The results reveal knowledge-creation activities such as problem definition,brainstorming, programming and system documentation. Students use the Internet, books,class notes, class presentations, senior students and professional software developers as sources of information. Mobile phones and BlackBerry devices facilitate knowledge-creation.Challenges to knowledge-creation are the lack of material and financial resources,a lack of technical skills, a lack of time, students staying off-campus and ambivalent team members.Conclusion: The conclusion drawn from this study is that student teams are capable of creating knowledge (a working system just like professional teams, but the knowledge-creation process is slightly different.

  8. Credit creation and control: an unresolved issue in Islamic banking

    OpenAIRE

    Hasan, Zubair

    2008-01-01

    Abstract. This paper deals with a still unresolved issue - credit creation and control- in an interest free banking system. The available literature on the subject is scanty, controversial and inconclusive. The paper holds that credit creation per se is not un-Islamic; the essential point is how credit is generated and used. It argues that credit creation cannot be banished; it is an imperative for frictionless adjustment of money supply to unavoidable fluctuations in its demand in modern...

  9. Perturbative neutrino pair creation by an external source

    CERN Document Server

    Koers, H

    2004-01-01

    We consider the rate of fermion-antifermion pair creation by an external field. We derive a rate formula that is valid for a coupling with arbitrary vector and axial vector components to first order in perturbation theory. This is then applied to study the creation of neutrinos by nuclear matter, a problem with astrophysical relevance. We present an estimate for the creation rate per unit volume, compare this to previous results and comment on the role of the neutrino mass.

  10. Co-creation, Prevailing Streams and a Future Design Trajectory

    DEFF Research Database (Denmark)

    Degnegaard, Rex

    2014-01-01

    Co-creation as a concept has won terrain over the past 10 years. In practice as well as in literature, co-creation is climbing the agenda in relation to contemporary opportunities and challenges within management, organisation design and change initiatives. This paper aims to build an overview of...... of significance to business and society. The paper highlights new co-creation-related issues and challenges. Further, the paper crystallises an emerging design trajectory in theory and practice....

  11. Knowledge Creation Systems in Seven-Eleven Japan

    Institute of Scientific and Technical Information of China (English)

    SENOO Dai

    2004-01-01

    Japanese convenience store chain Seven-Eleven Japan (hereinafter "SEJ") has been profitable for 30 years by constantly anticipating changing trends regardless of the severe business environment. In this paper, the knowledge creation process and its supportive systems in SEJ to examine how information system can support knowledge creation are described. Using case study method, the knowledge creation theory is applied to SE J, and the results show that facilitating "dialogue" and reinforcing "creative routine" might be the most important functions of information system to support knowledge creation.

  12. Pin Hole Discharge Creation in Na2SO4 Water Solutions

    OpenAIRE

    Lucie Hlavatá; Rodica Serbanescu; Lenka Hlochová; Zdenka Kozáková; František Krčma

    2013-01-01

    This work deals with the diaphragm discharge generated in water solutions containing Na2SO4 as a supporting electrolyte. The solution conductivity was varied in the range of 270 ÷ 750 µScm-1. The batch plasma reactor with volume of 100 ml was divided into two electrode spaces by the Shapal-MTM ceramics dielectric barrier with a pin-hole (diameter of 0.6 mm). Three variable barrier thicknesses (0.3; 0.7 and 1.5 mm) and non-pulsed DC voltage up to 2 kV were used for the discharge creation. Each...

  13. Plasma turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Horton, W. [Univ. of Texas, Austin, TX (United States). Inst. for Fusion Studies; Hu, G. [Globalstar LP, San Jose, CA (United States)

    1998-07-01

    The origin of plasma turbulence from currents and spatial gradients in plasmas is described and shown to lead to the dominant transport mechanism in many plasma regimes. A wide variety of turbulent transport mechanism exists in plasmas. In this survey the authors summarize some of the universally observed plasma transport rates.

  14. Effect of temperature on deposition layer formation in HBr/N2/fluorocarbon-based plasma

    Science.gov (United States)

    Iwase, Taku; Yokogawa, Kenetsu; Mori, Masahito

    2017-06-01

    The effects of wafer temperature on etching rate and surface composition were investigated to clarify the surface reaction mechanism under HBr/N2/fluorocarbon-based gas plasma for developing a process for three-dimensional NAND flash devices. The etching rates of both polycrystalline silicon (poly-Si) and SiO2 were found to increase at a wafer temperature of 20 °C as compared with those at 60 °C. Comparing the gas combination of fluorocarbon/N2 and HBr/N2 mixtures, the temperature dependence of SiO2 etching rates was considered to relevant to the sticking probability of fluorocarbon polymers. To determine the cause of the temperature dependence of the poly-Si etching rate, surface composition was evaluated by thermal-desorption-spectroscopy and laser-sputtered-neutral-mass-spectrometry analyses. Ammonium bromide was confirmed in the deposition film at a wafer temperature of 20 °C. The observed increase in poly-Si etching rate at lower temperatures was possibly caused by increased amounts of nitrogen, hydrogen, and bromine fixed to the surface with the formation of ammonium bromide.

  15. Microstructure and performance of rare earth element-strengthened plasma-facing tungsten material

    Science.gov (United States)

    Luo, Laima; Shi, Jing; Lin, Jinshan; Zan, Xiang; Zhu, Xiaoyong; Xu, Qiu; Wu, Yucheng

    2016-09-01

    Pure W and W-(2%, 5%, 10%) Lu alloys were manufactured via mechanical alloying for 20 h and a spark plasma sintering process at 1,873 K for 2 min. The effects of Lu doping on the microstructure and performance of W were investigated using various techniques. For irradiation performance analysis, thermal desorption spectroscopy (TDS) measurements were performed from room temperature to 1,000 K via infrared irradiation with a heating rate of 1 K/s after implantations of He+ and D+ ions. TDS measurements were conducted to investigate D retention behavior. Microhardness was dramatically enhanced, and the density initially increased and then decreased with Lu content. The D retention performance followed the same trend as the density. Second-phase particles identified as Lu2O3 particles were completely distributed over the W grain boundaries and generated an effective grain refinement. Transgranular and intergranular fracture modes were observed on the fracture surface of the sintered W-Lu samples, indicating some improvement of strength and toughness. The amount and distribution of Lu substantially affected the properties of W. Among the investigated alloy compositions, W-5%Lu exhibited the best overall performance.

  16. FY 2000 report on the results of the regional consortium R and D project - Regional consortium energy field. First year report. Development of the process for creation of new functional materials using electron beam excited plasma; 2000 nendo chiiki consortium kenkyu kaihatsu jigyo - chiiki consortium energy bun'ya. Denshi beam reiki plasma wo mochiita shinkino zairyo sosei process no kaihatsu (dai 1 nendo) seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    The development of manufacturing technology was proceeded with for a high speed nitriding system using electron beam excited plasma device which realizes high dissociation for nitrogen molecules and controls the plasma state. By the device, the following are aimed at: high quality/high speed nitriding, formation of super-hard cubic system boron nitride (c-BN) and carbon nitride (CN) films on the surface of tools, and formation of TiO{sub 2} thin films with high infrared reflectance and environmental purification photocatalyst function. TiO{sub 2} thin films are assumed to be applied to window glass by making use of the high performance heat mirror function as well as the environmental purification function. Studies were made in the following 6 fields: 1)development of small electron beam excitation plasma source; 2) development of high speed nitrided container; 3) establishment of technology for real-time monitoring of radicals and ions; 4) design/trial manufacture of a device to form super-hard nitrided thin films; 5) development of heat mirror film formation device; 6) establishment of a method to evaluate effects of photocatalyst. (NEDO)

  17. Pair Creation at Large Inherent Angles

    Energy Technology Data Exchange (ETDEWEB)

    Chen, P.; Tauchi, T.; Schroeder, D.V.; /SLAC

    2007-04-25

    In the next-generation linear colliders, the low-energy e{sup +}e{sup -} pairs created during the collision of high-energy e{sup +}e{sup -} beams would cause potential deleterious background problems to the detectors. At low collider energies, the pairs are made essentially by the incoherent process, where the pair is created by the interaction of beamstrahlung photons on the individual particles in the oncoming beam. This problem was first identified by Zolotarev, et al[1]. At energies where the beamstrahlung parameter {Upsilon} lies approximately in the range 0.6 {approx}< {Upsilon} {approx}< 100, pair creation from the beamstrahlung photons is dominated by a coherent process, first noted by Chen[2]. The seriousness of this pair creation problem lies in the transverse momenta that the pair particles carry when leaving the interaction point (IP) with large angles. One source of transverse momentum is from the kick by the field of the oncoming beam which results in an outcoming angle {theta} {proportional_to} 1/{radical}x, where x is the fractional energy of the particle relative to the initial beam particle energy[2,3]. As was shown in Ref. 131, there in fact exists an energy threshold for the coherent pairs, where x{sub th} {approx}> 1/2{Upsilon}. Thus within a tolerable exiting angle, there exists an upper limit for {Upsilon} where all coherent pairs would leave the detector through the exhaust port[4]. A somewhat different analysis has been done by Schroeder[5]. In the next generation of linear colliders, as it occurs, the coherent pairs can be exponentially suppressed[2] by properly choosing the {Upsilon}({approx}< 0.6). When this is achieved, the incoherent pairs becomes dominant. Since the central issue is the transverse momentum for particles with large angles, we notice that there is another source for it. Namely, when the pair particles are created at low energies, the intrinsic angles of these pairs when produced may already be large. This issue was

  18. 17 CFR 201.1100 - Creation of Fair Fund.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Creation of Fair Fund. 201... PRACTICE Fair Fund and Disgorgement Plans § 201.1100 Creation of Fair Fund. In any agency process initiated... requiring the payment of disgorgement by a respondent and also assessing a civil money penalty against that...

  19. Opening the black box: knowledge creation in data teams

    NARCIS (Netherlands)

    Hubers, Mireille D.; Poortman, Cindy L.; Schildkamp, Kim; Pieters, Jules M.; Handelzalts, Adam

    2016-01-01

    Purpose – In this study, Nonaka and Takeuchi’s socialization, externalization, combination and internalization (SECI) model of knowledge creation is used to gain insight into the process of knowledge creation in data teams. These teams are composed of school leaders and teachers, who work together t

  20. Opening the black box: knowledge creation in data teams

    NARCIS (Netherlands)

    Hubers, Mireille D.; Poortman, Cindy L.; Schildkamp, Kim; Pieters, Jules M.; Handelzalts, Adam

    2016-01-01

    Purpose: – In this study, Nonaka and Takeuchi’s socialization, externalization, combination and internalization (SECI) model of knowledge creation is used to gain insight into the process of knowledge creation in data teams. These teams are composed of school leaders and teachers, who work together

  1. Should Creation Be Included in the Biology Curriculum?

    Science.gov (United States)

    Skoog, Gerald

    The author discusses the activities and goals of advocates of creation science as these persons and groups work to bring about the teaching of creationism in high school science courses in which evolution is taught. It is the author's belief that the anti-evolutionism movement was stimulated by the science curriculum improvement activities of the…

  2. Legal and Judicial Problems in Mandating Equal Time for Creationism.

    Science.gov (United States)

    Skoog, Gerald

    This paper, presented at the annual meeting of the National Association of Biology Teachers, is focused on legal and judicial problems in mandating equal time for creationism. Past events provide evidence that legislation, policies, and local resolutions that require science textbooks and curricula to include the Genesis account of creation are…

  3. Creation of unstable particles and decoherence in semiclassical cosmology

    CERN Document Server

    Castagnino, M A; Lombardo, F C; Castagnino, Mario; Landau, Susana; Lombardo, Fernando C.

    1999-01-01

    We consider a simple cosmological model in order to show the importance of unstable particle creation for the validity of the semiclassical approximation. Using the mathematical structure of rigged Hilbert spaces we show that particle creation is the seed of decoherence which enables the quantum to classical transition.

  4. Research on Education in the Knowledge Creation Paradigm

    Science.gov (United States)

    Tan, Seng Chee; Ow, John; Chai, ChingSing; Teo, Chew-Lee; Yeo, Jennifer

    2014-01-01

    To better prepare learners for the "knowledge society," educators in Singapore have embarked on a journey in experimenting with knowledge creation pedagogy in classrooms. The Knowledge Creation and Innovative Design Centre was set up to further coordinate this effort. In this article, the authors give an account of the historical…

  5. Multi-pair states in electron–positron pair creation

    Directory of Open Access Journals (Sweden)

    Anton Wöllert

    2016-09-01

    Full Text Available Ultra strong electromagnetic fields can lead to spontaneous creation of single or multiple electron–positron pairs. A quantum field theoretical treatment of the pair creation process combined with numerical methods provides a description of the fermionic quantum field state, from which all observables of the multiple electron–positron pairs can be inferred. This allows to study the complex multi-particle dynamics of electron–positron pair creation in-depth, including multi-pair statistics as well as momentum distributions and spin. To illustrate the potential benefit of this approach, it is applied to the intermediate regime of pair creation between nonperturbative Schwinger pair creation and perturbative multiphoton pair creation where the creation of multi-pair states becomes nonnegligible but cascades do not yet set in. Furthermore, it is demonstrated how spin and helicity of the created electrons and positrons are affected by the polarization of the counterpropagating laser fields, which induce the creation of electron–positron pairs.

  6. Value Co-Creation: Best of TIM Review

    DEFF Research Database (Denmark)

    The intention of the present book is to address the ambiguity problem by contributing to the semantic refinement of the value co-creation paradigm with a focus on both its business - and innovation-related aspects. It comprises 16 of the best articles on value co-creation published by Technology...

  7. Value Co-Creation: Best of TIM Review

    DEFF Research Database (Denmark)

    The intention of the present book is to address the ambiguity problem by contributing to the semantic refinement of the value co-creation paradigm with a focus on both its business - and innovation-related aspects. It comprises 16 of the best articles on value co-creation published by Technology...

  8. The Creation of Man and Woman in Early Jewish Literature

    NARCIS (Netherlands)

    Ruiten, J.T.A.G.M. van; Luttikhuizen, G P

    2000-01-01

    J.T.A.G.M. van Ruiten, “The Creation of Man and Woman in Early Jewish Literature,” in The Creation of Man and Woman: Interpretations of the Biblical Narratives in Jewish and Christian Traditions (ed. Gerard P. Luttikhuizen; Themes in Biblical Narrative 3; Leiden, Boston, and Köln: Brill, 2000), 34-6

  9. Value co-creation in service interactions: dimensions and antecedents

    NARCIS (Netherlands)

    Neghina, C.; Caniëls, M.C.J.; Bloemer, J.M.M.; Birgelen, M.J.H. van

    2013-01-01

    The purpose of this article is to further develop the conceptualization of value co-creation and discuss its dimensions and antecedents. We propose that in service interactions, value co-creation should be understood as a joint collaborative activity between service employees and customers consi

  10. Plasma harmonics

    CERN Document Server

    Ganeev, Rashid A

    2014-01-01

    Preface; Why plasma harmonics? A very brief introduction Early stage of plasma harmonic studies - hopes and frustrations New developments in plasma harmonics studies: first successes Improvements of plasma harmonics; Theoretical basics of plasma harmonics; Basics of HHG Harmonic generation in fullerenes using few-cycle pulsesVarious approaches for description of observed peculiarities of resonant enhancement of a single harmonic in laser plasmaTwo-colour pump resonance-induced enhancement of odd and even harmonics from a tin plasmaCalculations of single harmonic generation from Mn plasma;Low-o

  11. Job Creation by Firms in Denmark

    DEFF Research Database (Denmark)

    Ibsen, Rikke Falkner; Westergård-Nielsen, Niels

    -offs and mergers. The analysis will make it possible to differentiate between net and gross creation of jobs because we can follow each single individual in and out of jobs. We have for Denmark found that size on its own does not have a big impact, but young firms are much more likely to contribute to a positive...... Denmark lost 186,000 jobs in the private sector. The question is where and how could these jobs be recreated. Are these issues specific to industries or are they universal? The data used is register data on workplaces and firms for the period 1980-2007. The base unit of data is the workplace. The company...... time. A complication here is that firms switch ID over time because of change of ownership, mergers and divisions. Data must be corrected so that these administrative issues will not affect the survival of firms. The data are used in a way where we can cover firm birth and firm death, spin...

  12. Job Creation by Firms in Denmark

    DEFF Research Database (Denmark)

    Ibsen, Rikke Falkner; Westergård-Nielsen, Niels

    (firm) is the legal entity. A company can have many sites, and one of the ways companies can grow is by expanding with multiple sites. This can happen by mergers and acquisitions but can also happen by creating "daughter workplaces". It is therefore essential to look at workplaces and firms at the same...... time. A complication here is that firms switch ID over time because of change of ownership, mergers and divisions. Data must be corrected so that these administrative issues will not affect the survival of firms. The data are used in a way where we can cover firm birth and firm death, spin......-offs and mergers. The analysis will make it possible to differentiate between net and gross creation of jobs because we can follow each single individual in and out of jobs. We have for Denmark found that size on its own does not have a big impact, but young firms are much more likely to contribute to a positive...

  13. Self-creation cosmology - a review

    CERN Document Server

    Barber, Garth Antony

    2010-01-01

    Over 60 authors have worked on various versions of self-creation cosmology (SCC) since the original paper in 1982. These papers adapted the Brans Dicke theory to create mass out of the universe's self contained scalar, gravitational and matter fields. The most recent 2002 version of the theory was concordant with all previous standard tests of GR but was falsified by the Gravity Probe B geodetic precession experiment. Here the different versions of the theory are reviewed and it is noted that the 2002 theory not only reduces to the second 1982 theory when cast into a the 'true' form of the scalar field stress-energy tensor but also in that form it passes the GP-B test. Further experiments are able to resolve the SCC-GR degeneracy, one of which is briefly described. SCC may be able to explain some intriguing anomalies also, in the spherically symmetric One-Body problem, it transpires that the temporal Newtonian potential is three times larger than the spatial one. Cosmological solutions to the field equations,...

  14. FROM THE HISTORY OF LASER CREATION

    Directory of Open Access Journals (Sweden)

    I.M. Belousova

    2014-03-01

    Full Text Available The paper briefly describes the history of formation of a new science direction - quantum electronics, associated with the discovery of masers and lasers by scientists from the USA (Ch. Townes and the USSR (N.G. Basov and A. M. Prokhorov. The world's first ruby laser designed by T. Maiman is described. Some historical events devoted to creation and research of lasers are given in which the author of the paper as well as research workers from Vavilov State Optical Institute, ITMO University and LOMO have taken direct part in the development of solid-state and gas lasers (helium-neon, photodissociation, CO2-lasers and laser optical systems. Contribution of researchers from Vavilov State Optical Institute, LOMO and ITMO University to large-scale programs on development of lasers for laser nuclear fusion, laser weapons and “Phobos” program is shown. The paper deals in brief with new issues of development and application of lasers, mainly, within the project of laser orbital space station of the future, for the conversion of solar energy into laser radiation. Description of idea of solar energy transformation by fullerene-oxygen laser is presented. The patent for it has been taken out by Vavilov State Optical Institute. Developed fullerene-oxygen-iodine laser and laser structure models for industrial applications and solar energy conversion into laser radiation are described. Parameters for hypothetical laser-optical system of the future space station are given.

  15. Quantum graviton creation in a model universe

    Science.gov (United States)

    Berger, B. K.

    1974-01-01

    Consideration of the mechanism of production of gravitons in the empty, anisotropic, spatially inhomogeneous Gowdy three-torus cosmology. The Gowdy cosmology is an exact solution of the vacuum Einstein equations and is obtained as a generalization of the homogeneous empty Bianchi Type I (Kasner) cosmology by permitting the metric components to depend on one of the space variables in addition to time. The Hamiltonian methods of Arnowitt, Deser, and Misner are employed to identify the dynamical variables which are to be quantized. The WKB regime solution is identical to that found by Doroshkevich, Zel'dovich, and Novikov (DZN) for a universe containing collisionless anisotropic radiation. Using a procedure similar to that of Parker (1971) or Zel'dovich and Starobinskii (1971) for defining quantum number, it is found that the DZN large-time radiation consists of quanta (gravitons) created from an initial vacuum. The quantum behavior is much like the semiclassical enhancement of quantum number with the added feature of creation of quanta from vacuum fluctuations.

  16. Bohr's Creation of his Quantum Atom

    Science.gov (United States)

    Heilbron, John

    2013-04-01

    Fresh letters throw new light on the content and state of Bohr's mind before and during his creation of the quantum atom. His mental furniture then included the atomic models of the English school, the quantum puzzles of Continental theorists, and the results of his own studies of the electron theory of metals. It also included the poetry of Goethe, plays of Ibsen and Shakespeare, novels of Dickens, and rhapsodies of Kierkegaard and Carlyle. The mind that held these diverse ingredients together oscillated between enthusiasm and dejection during the year in which Bohr took up the problem of atomic structure. He spent most of that year in England, which separated him for extended periods from his close-knit family and friends. Correspondence with his fianc'ee, Margrethe Nørlund, soon to be published, reports his ups and downs as he adjusted to J.J. Thomson, Ernest Rutherford, the English language, and the uneven course of his work. In helping to smooth out his moods, Margrethe played an important and perhaps an enabling role in his creative process.

  17. RELATIONAL MECHANISMS IN INNOVATION CO-CREATION

    Directory of Open Access Journals (Sweden)

    Rodica Boier

    2014-12-01

    Full Text Available Increasingly, producers and customers establish relationships to mutually undertake the development of an innovative product. Consequently, it will be always of interest for an innovative company to know the degree to which different related suppliers are willing to form partnerships by participating in its new product development process. Several managerial implications flow from the link between relationship marketing and innovation processes, ranging from tactical product-related decisions to strategic competitor-related decisions, usually made in a relatively short period of time. Dedicated customer relationship systems track the interactions with customers and improve the flow of ideas for new products. When trying to develop long-term customer relationships, the ability to provide superior value to stakeholders is a must. Through carefully conducted relationships, customers are linked with the innovation company during the entire innovation process, and create a space for mutual understanding, learning and value co-creation. In order to co-create business value through online, also combined with offline innovation-related activities, customer orientation should be implemented throughout the organization – its culture, their systems, including the whole range of interactions.

  18. THE CREATION AND DEVELOPMENT OF JOB IN NIGERIA: ENTREPRENEURSHIP ENLIGHTENMENT

    Directory of Open Access Journals (Sweden)

    Money, Udih

    2016-01-01

    Full Text Available This paper is an opinion one that examined the significant role of entrepreneurship enlightenment in the creation and development of job in Nigeria. Entrepreneurship enlightenment that is continuous and reaching the citizens will help in the creation and development of job. It is viewed that entrepreneurship enlightenment is a giant stride towards creation and development of job in Nigeria. This paper also touches the challenges facing entrepreneurship development and job creation in Nigeria. To this end, the Federal, State and Local Government should have a functional policy that is gear towards job creation with respect to entrepreneurial enlightenment. This will help to sustain and create jobs through continuous and reaching entrepreneurship enlightenment.

  19. What does existing research say about value co-creation?

    DEFF Research Database (Denmark)

    Thomsen, Merethe Stjerne; Tanev, Stoyan; Pedrosa, Alex

    2010-01-01

    -customer interaction events, which are extremely personal with unique products, services and experiences. In general the paper is starting up a conceptual refinement on value co-creation by addressing the key characteristics of current literature and driving forces of co-creation.......The paper presents a literature review on co-creation, which is summarized into emerging research areas and insights as a basis for a future research agenda for value co-creation. The search methodology is based on a keywords search on ISI Web of Knowledge, leading to 82 articles with a summary...... of four emerging subject areas within marketing science, service management, new product development & innovation and general business and management. The four subject areas lead to new key driving forces of value co-creation by involving the customers in experience networks, where both creating...

  20. Useful Business Cases: Value Creation in IS Projects

    DEFF Research Database (Denmark)

    Nielsen, Peter Axel; Persson, John Stouby

    2016-01-01

    during implementation and value creation. This article presents lessons learned from our action research, lessons that we incorporated into a business case method and subsequently evaluated with IS managers. There are three lessons on: (1) improving the content of business cases, (2) how to develop......Business cases have become popular as part of managing value creation in IS projects. Nevertheless, business cases are often poorly linked to value creation activities and organizations struggle to develop business cases that are useful and express more than simple cost savings. This action...... business cases, and (3) the use of business cases in subsequent value creation. These lessons summarize our findings and the contributions are that we in the business case method propose to: (1) include minimal contents, (2) develop social commitment, and (3) structure for dynamic use during value creation...

  1. Study of the hydrogen behavior in amorphous hydrogenated materials of type a - C:H and a - SiC:H facing fusion reactor plasma; Etude du comportament de l`hydrogene dans des materiaux amorphes hydrogenes de type a - C:H et a - SiC:H devant faire face au plasma des reacteurs a fusion

    Energy Technology Data Exchange (ETDEWEB)

    Barbier, G. [Lyon-1 Univ., 69 - Villeurbanne (France). Inst. de Physique Nucleaire

    1997-04-10

    Plasma facing components of controlled fusion test devices (tokamaks) are submitted to several constraints (irradiation, high temperatures). The erosion (physical sputtering and chemical erosion) and the hydrogen recycling (retention and desorption) of these materials influence many plasma parameters and thus affect drastically the tokamak running. First, we will describe the different plasma-material interactions. It will be pointed out, how erosion and hydrogen recycling are strongly related to both chemical and physical properties of the material. In order to reduce these interactions, we have selected two amorphous hydrogenated materials (a-C:H and a-SiC:H), which are known for their good thermal and chemical qualities. Some samples have been then implanted with lithium ions at different fluences. Our materials have been then irradiated with deuterium ions at low energy. From our results, it is shown that both the lithium implantation and the use of an a - SiC:H substrate can be beneficial in enhancing the hydrogen retention. These results were completed with thermal desorption studies of these materials. It was evidenced that the hydrogen fixation was more efficient in a-SiC:H than in a-C:H substrate. Results in good agreement with those described above have been obtained by exposing a - C:H and a - SiC:H samples to the scrape off layer of the tokamak of Varennes (TdeV, Canada). A modelling of hydrogen diffusion under irradiation has been also proposed. (author) 176 refs.

  2. Dusty plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Fortov, Vladimir E; Khrapak, Aleksei G; Molotkov, Vladimir I; Petrov, Oleg F [Institute for High Energy Densities, Associated Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russian Federation); Khrapak, Sergei A [Max-Planck-Institut fur Extraterrestrische Physik, Garching (Germany)

    2004-05-31

    The properties of dusty plasmas - low-temperature plasmas containing charged macroparticles - are considered. The most important elementary processes in dusty plasmas and the forces acting on dust particles are investigated. The results of experimental and theoretical investigations of different states of strongly nonideal dusty plasmas - crystal-like, liquid-like, gas-like - are summarized. Waves and oscillations in dusty plasmas, as well as their damping and instability mechanisms, are studied. Some results on dusty plasma investigated under microgravity conditions are presented. New directions of experimental research and potential applications of dusty plasmas are discussed. (reviews of topical problems)

  3. The potential of shared value creation: a theoretical analysis

    Directory of Open Access Journals (Sweden)

    Victor Danciu

    2016-06-01

    Full Text Available The urgent issues economy, environment and society are facing need new approaches which allow a well-balanced sharing of value created by the economy. A step forward is the concept of shared value creation. This paper aims to analyze the main features, the content of strategy of shared value creation and to propose the social innovation as main strategic way of shared value creation. At the beginning, the drivers and challenges of shared value creation are investigated in a systematized manner, in order to better understand why this new way of doing business is needed. Then, the concept and the three levels of shared value creation are investigated as sources of economic, environmental and social benefits that a business creates. These benefits depend on how efficient and diligent the company works. We are advancing the social innovation as main strategy having the greatest potential to create value with economic, environmental and social benefits. Finally, a framework for measurement of shared value creation is included. This framework is aiming at giving a tool for checking up the potential the shared value creation has for solving environmental and social issues.

  4. Sources of Value Creation in Born Global Companies

    Directory of Open Access Journals (Sweden)

    Augustyniak Dobrochna

    2017-06-01

    Full Text Available Research about the phenomenon of rapid internationalization of small and medium size companies has evolved over the last two decades. Nevertheless, questions about business models or value creation in born global enterprises are rarely addressed in the literature. The objective of this article is to develop a theoretical framework for analyzing the sources of value creation in the business models of international new ventures (INV global companies, starting with adapting the model by Amit and Zott [2001, 2010] to early internationalizing venture. Current literature on international entrepreneurship, business models and value creation is also used as a basis for suggesting future empirical research recommendations.

  5. Value Creation in the Context of Sustainable Corporate Social Responsibility

    Science.gov (United States)

    Šmida, Ľubomír; Sakál, Peter

    2014-12-01

    Under the influence of the new rules of the economy and the society, companies are achieving a notional line of a necessary change in the approach to creating new value, wealth. Implementation of changes in the system of wealth creation requires a review of existing assumptions of unlimited growth of the global economy and wealth creation in the environment accepting economic interests, society and the environment as a holistic unit. The main purpose of this paper is the clarification of a new requirements for business, presentation of the questionnaire survey Sustainable Corporate Social Responsibility and inform on value creation in the context of Sustainable Corporate Social Responsibility.

  6. The Framework of Knowledge Creation for Online Learning Environments

    Directory of Open Access Journals (Sweden)

    Hsiu-Mei Huang

    2004-02-01

    Full Text Available Abstract: In today’s competitive global economy characterized by knowledge acquisition, the concept of knowledge management has become increasingly prevalent in academic and business practices. Knowledge creation is an important factor and remains a source of competitive advantage over knowledge management. Information technology facilitates knowledge management practices by disseminating knowledge and making codified knowledge retrievable. Thus, this paper proposes a framework of knowledge creation in online learning environments. In addition, the features and issues of knowledge creation in these environments are discussed.

  7. Creationism and Evolution in the Schools: The Constitutional Issues.

    Science.gov (United States)

    Sorenson, Gail Paulus; Fischer, Louis

    1983-01-01

    A review of the major legal cases concerning the curricular debate over evolution and creationism shows how the courts, in recent cases, have applied fundamental constitutional principles in a way that preserves both intellectual freedom and freedom of belief. (CM)

  8. Evolution and Dynamics of a Matter creation model

    CERN Document Server

    Pan, Supriya; Paliathanasis, Andronikos; Slagter, Reinoud Jan

    2016-01-01

    In the flat Friedmann-Lema\\^{\\i}tre-Robertson-Walker (FLRW) geometry, we consider the expansion of the universe powered by the gravitationally induced `adiabatic' matter creation. To demonstrate how matter creation works well with the expanding universe, we have considered a general creation rate and analyzed this rate in the framework of dynamical analysis. The dynamical analysis hints the presence of a non-singular universe (without the big bang singularity) with two successive accelerated phases, one at the very early phase of the universe (i.e., inflation), and the other one describes the current accelerating universe, where this early, late accelerated phases are associated with an unstable fixed point (i.e., repeller) and a stable fixed (attractor) points, respectively. We have described this phenomena by analytic solutions of the Hubble function and the scale factor of the FLRW universe. Using Jacobi Last multiplier method, we have found a Lagrangian for this matter creation rate describing this scenar...

  9. Black Hole Creation at the Birth of the Universe

    Institute of Scientific and Technical Information of China (English)

    Wu Zhong-Chao

    2000-01-01

    We study the quantum creation of black hole pairs in the (anti-)de Sitter space background. These black hole pairs in the Kerr-Newman family are created from constrained instantons. At the Wentzel-Kramers-Brillouin level, for the chargeless and nonrotating case, the relative creation probability is the exponential of (the negative of) the entropy of the universe. Also for the remaining cases of the family, the creation probability is the exponential of (the negative of) one quarter of the sum of the inner and outer black hole horizon areas. In the absence of a general no-boundary proposal for open universes, we treat the creations of the closed and the open universes in the same way.

  10. The Game Object Model and expansive learning: Creation ...

    African Journals Online (AJOL)

    The Game Object Model and expansive learning: Creation, instantiation, ... into the design, integration, evaluation and use of video games in learning and teaching. ... individual understanding of the role of games in education and transformed ...

  11. Creation, Its Processes, and Significance (Samkhya Evolution and Involution

    Directory of Open Access Journals (Sweden)

    Pratibha Gramann

    2015-11-01

    Full Text Available Science, religions, and cultural traditions develop theories and creative descriptions about the origin of the universe and meaning of life. These theories have both similarities and differences regarding the cause and effect of creation, and life as human beings know it. Religions and cultural traditions primarily adhere to a personal God as creator and ruler. Science has gone in the opposite direction of denying the existence of a God. A definitive cause of creation has not been scientifically found. Science may find a comparable, suitable match in the ancient thought of Samkhya, written in the 500-800 BC time. Samkhya is probably the first complete philosophical description of the origin and evolution of creation. The three basic energetics of Samkhya are comparable to the basic energies of physics. This paper addresses the hypothesis that the evolution and origin of creation stem from the 3 energies gunas of materiality prakriti described in ancient Samkhya.

  12. A Reflection on Knowledge Creation and Knowledge Transfer

    Institute of Scientific and Technical Information of China (English)

    Xie Yuan-yuan

    2014-01-01

    The aim of this article is to address the issue concerning knowledge management. Knowledge creation and transfer are fully examined through Nancy Dixon’s five ways and Nonaka and Takeuchi’s four models.

  13. Polarization operator approach to pair creation in short laser pulses

    CERN Document Server

    Meuren, Sebastian; Keitel, Christoph H; Di Piazza, Antonino

    2014-01-01

    We investigate the nonlinear Breit-Wheeler process inside short laser pulses, i.e. the creation of an electron-positron pair induced by a gamma photon inside a plane-wave background field. To obtain the total pair-creation probability we verify (to leading-order) the cutting rule for the polarization operator in the realm of strong-field QED by an explicit calculation. Furthermore, a double-integral representation for the leading-order contribution to the field-dependent part of the polarization operator is derived. The combination of both results yields a compact expression for the total pair-creation probability inside an arbitrary plane-wave background field. It is shown numerically that with presently available technology pair-creation probabilities of the order of ten percent could be reached for a single gamma photon.

  14. Mobile Learning: Creation, delivery and evaluation of eBooks

    NARCIS (Netherlands)

    Kalz, Marco; Ternier, Stefaan

    2012-01-01

    Kalz, M., & Ternier, S. (2012, 10 December). Mobile Learning: Creation, delivery and evaluation of eBooks. Workshop for TPG Academy and a South African Delegation, Heerlen, The Netherlands: Open Universiteit in the Netherlands.

  15. Wetland creation and restoration : description and summary of the literature

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report provides a hard copy of the bibliographic information contained in the digital Wetland Creation/Restoration Data Base. One thousand one hundred data base...

  16. Remote two-qubit state creation and its robustness

    Science.gov (United States)

    Stolze, J.; Zenchuk, A. I.

    2016-08-01

    We consider the problem of remote two-qubit state creation using the two-qubit excitation pure initial state of the sender. The communication line is based on the optimized boundary-controlled chain with two pairs of properly adjusted coupling constants. We show that the communication line can be characterized by a set of parameters independent of the initial state of the sender. These parameters are permanent attributes of a communication line and can be either calculated theoretically or measured in experiment. In particular, they determine the creatable subregion of the receiver's state space. The creation of a particular state within the creatable region is achieved by a proper choice of the independent parameters of the sender's initial state (control parameters) and reduces to the solvability of a certain system of algebraic equations. The creation of the two-qubit Werner state is considered as an example. We also study the effects of imperfections of the chain on the state creation.

  17. Hemingway's Political Views in His Second Period of Creation

    Institute of Scientific and Technical Information of China (English)

    许颖

    2009-01-01

    Based on the influence of different relationship between general ideology and authorial ideology on Hemingway's works in the second period of his creation, the thesis aims to study the different reflection of his political interest from the perspective of ideology.

  18. Hemingway's Political Views in His First Period of Creation

    Institute of Scientific and Technical Information of China (English)

    许颖

    2009-01-01

    Based on the influence of different rehtionship between general ideology and authorial ideology on Hemingway's works in the first period of his creation, the thesis aims to study the different reflection of his political interest from the perspective of ideology.

  19. The Politics of States', Local Governments' Creation and Nigeria's ...

    African Journals Online (AJOL)

    Nekky Umera

    bombarded the then colonial government with an avalanche of requests for the creation of .... political support in their bid to gain the rein of governance especially from the ..... While big states can threaten the corporate existence and stability ...

  20. What does existing research say about value co-creation?

    DEFF Research Database (Denmark)

    Thomsen, Merethe Stjerne; Tanev, Stoyan; Pedrosa, Alex

    2010-01-01

    of four emerging subject areas within marketing science, service management, new product development & innovation and general business and management. The four subject areas lead to new key driving forces of value co-creation by involving the customers in experience networks, where both creating...... and sustaining a rewarding virtual customer environment should not be underestimated. Co-creation is also a key component within service management, where a product is mainly an enabler of a service, and it influences the general field of product development and innovation. Customers are engaged through company......-customer interaction events, which are extremely personal with unique products, services and experiences. In general the paper is starting up a conceptual refinement on value co-creation by addressing the key characteristics of current literature and driving forces of co-creation....

  1. Mobile Learning: Creation, delivery and evaluation of eBooks

    NARCIS (Netherlands)

    Kalz, Marco; Ternier, Stefaan

    2012-01-01

    Kalz, M., & Ternier, S. (2012, 10 December). Mobile Learning: Creation, delivery and evaluation of eBooks. Workshop for TPG Academy and a South African Delegation, Heerlen, The Netherlands: Open Universiteit in the Netherlands.

  2. Plasma waves

    CERN Document Server

    Swanson, DG

    1989-01-01

    Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. Th

  3. Plasma astrophysics

    CERN Document Server

    Kaplan, S A; ter Haar, D

    2013-01-01

    Plasma Astrophysics is a translation from the Russian language; the topics discussed are based on lectures given by V.N. Tsytovich at several universities. The book describes the physics of the various phenomena and their mathematical formulation connected with plasma astrophysics. This book also explains the theory of the interaction of fast particles plasma, their radiation activities, as well as the plasma behavior when exposed to a very strong magnetic field. The text describes the nature of collective plasma processes and of plasma turbulence. One author explains the method of elementary

  4. Influence of tungsten microstructure and ion flux on deuterium plasma-induced surface modifications and deuterium retention

    Energy Technology Data Exchange (ETDEWEB)

    Buzi, L., E-mail: l.buzi@fz-juelich.de [Forschungszentrum Jülich GmbH, Institut für Energie – und Klimaforschung - Plasmaphysik, Partner of the Trilateral Euregio Cluster (TEC), 52425 Jülich (Germany); FOM Institute DIFFER – Dutch Institute for Fundamental Energy Research, Partner in the Trilateral Euregio Cluster (Netherlands); Gent University, Sint-Pietersnieuwstraat 41, B-9000 Gent (Belgium); Université de Lorraine, Institut Jean Lamour, CNRS UMR 7198, Bvd. des Aiguillettes, F-54506 Vandoeuvre (France); De Temmerman, G. [FOM Institute DIFFER – Dutch Institute for Fundamental Energy Research, Partner in the Trilateral Euregio Cluster (Netherlands); Unterberg, B.; Reinhart, M.; Dittmar, T.; Matveev, D.; Linsmeier, Ch. [Forschungszentrum Jülich GmbH, Institut für Energie – und Klimaforschung - Plasmaphysik, Partner of the Trilateral Euregio Cluster (TEC), 52425 Jülich (Germany); Breuer, U. [Central Institute of Engineering, Electronics and Analytics, ZEA-3 Analytics, Research Centre Jülich GmbH, 52425 Jülich (Germany); Kreter, A. [Forschungszentrum Jülich GmbH, Institut für Energie – und Klimaforschung - Plasmaphysik, Partner of the Trilateral Euregio Cluster (TEC), 52425 Jülich (Germany); Van Oost, G. [Gent University, Sint-Pietersnieuwstraat 41, B-9000 Gent (Belgium)

    2015-08-15

    The influence of surface temperature, particle flux density and material microstructure on the surface morphology and deuterium retention was studied by exposing tungsten targets (20 μm and 40 μm grain size) to deuterium plasma at the same particle fluence (10{sup 26} m{sup −2}) and incident ion energy (40 eV) to two different ion fluxes (low flux: 10{sup 22} m{sup −2} s{sup −1}, high flux: 10{sup 24} m{sup −2} s{sup −1}). The maximum of deuterium retention was observed at ∼630 K for low flux density and at ∼870 K for high flux density, as indicated from the thermal desorption spectroscopy data (TDS). Scanning electron microscopy observations revealed the presence of blisters with a diameter of up to 1 μm which were formed at high flux density and high temperature (1170 K) contrasting with previously reported surface modification results at such exposure conditions.

  5. Investigation of microstructure and irradiation behavior of W–Nb/Ti composites prepared by spark plasma sintering

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jing-Bo [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Luo, Lai-Ma, E-mail: luolaima@126.com [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); National–Local Joint Engineering Research Centre of Nonferrous Metals and Processing Technology, Hefei 230009 (China); Zhao, Mei-Ling [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Xu, Qiu [Research Reactor Institute, Kyoto University, Osaka-Fu 590-0494 (Japan); Zan, Xiang [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); National–Local Joint Engineering Research Centre of Nonferrous Metals and Processing Technology, Hefei 230009 (China); Wu, Yu-Cheng, E-mail: ycwu@hfut.edu.cn [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); National–Local Joint Engineering Research Centre of Nonferrous Metals and Processing Technology, Hefei 230009 (China)

    2016-11-15

    W–Nb/Ti composites were prepared by machine milling and spark plasma sintering. Field–emission scanning electron microscopy, high–resolution transmission electron microscopy, and X-ray diffraction analyses were used to characterize the samples. Thermal desorption spectroscopy (TDS) was used to measure the deuterium retention after only deuterium irradiation. The deuterium retention in W–4wt%Ti–wt1%Nb was lower than that in pure W (D{sub 2}{sup +} flux ∼10{sup 22} ions/(m{sup 2} s), ion energy ∼5 keV), Nb and Ti will improve the deuterium irradiation resistance of tungsten composite. In addition, transgranular and intergranular fractures were observed on the surface of the W–4 wt% Ti–1 wt% Nb composite. A Ti{sub (X)}W{sub (1−X)} solid solution was formed during sintering. The maximum tensile strength (410.53 MPa) was detected in the W–4wt%Ti–1wt%Nb composite at 600 °C.

  6. Factors influencing the creation of the goodwill of enterpjrises

    Directory of Open Access Journals (Sweden)

    Vodzinský Vladimír

    1999-03-01

    Full Text Available The importance of the goodwill creation from the viewpoint of achieving the goals of enterprises is permanently growing in the transi-tive societies. In this paper, factors are analyzed that have to be respected by managing subject of the enterprises during the goodwill creation. But, problems that cause the goodwill misrepresentation (when it is evaluated by standard criteria are also analyzed.

  7. Semiclassical fermion pair creation in de Sitter spacetime

    Energy Technology Data Exchange (ETDEWEB)

    Stahl, Clément, E-mail: clement.stahl@icranet.org; Eckhard, Strobel, E-mail: eckhard.strobel@irap-phd.eu [ICRANet, Piazzale della Repubblica 10, 65122 Pescara (Italy); Dipartimento di Fisica, Università di Roma “La Sapienza”, Piazzale Aldo Moro 5, 00185 Rome (Italy); Université de Nice Sophia Antipolis, 28 Avenue de Valrose, 06103 Nice Cedex 2 (France)

    2015-12-17

    We present a method to semiclassically compute the pair creation rate of bosons and fermions in de Sitter spacetime. The results in the bosonic case agree with the ones in the literature. We find that for the constant electric field the fermionic and bosonic pair creation rate are the same. This analogy of bosons and fermions in the semiclassical limit is known from several flat spacetime examples.

  8. Higher dimensional strange quark matter solutions in self creation cosmology

    Science.gov (United States)

    Şen, R.; Aygün, S.

    2016-03-01

    In this study, we have generalized the higher dimensional flat Friedmann-Robertson-Walker (FRW) universe solutions for a cloud of string with perfect fluid attached strange quark matter (SQM) in Self Creation Cosmology (SCC). We have obtained that the cloud of string with perfect fluid does not survive and the string tension density vanishes for this model. However, we get dark energy model for strange quark matter with positive density and negative pressure in self creation cosmology.

  9. special issue: Cognition, imagination and institutions in demand creation

    OpenAIRE

    Brian J. Loasby

    2001-01-01

    Formal rationality plays a limited role in human cognition, which originated in the creation of patterns to interpret phenomena and link phenomena with action. The creation of new patterns rests on imagination, not logic, typically stimulated by a perceived inadequacy in established patterns. Internal routines of the brain and external institutions form structures of cognitive capital; the institutions of markets, including money prices, aid the development of consumption capital, which simpl...

  10. Creation of electromechanical device for electric vehicle traction

    Directory of Open Access Journals (Sweden)

    Денис Юрьевич Зубенко

    2016-10-01

    Full Text Available The problems of creation of electromechanical device for electric vehicle traction are considered in the article. The aim of creation this design are the replacement of the internal combustion engine on electromechanical device. For this electromechanical device are constructed model, which describe processes that occur in the electric drive of electromechanical device. Characteristics of the main modes of motion were recorded. The introduction of electromechanical device will reduce the level of emissions and reduce noise in the cities

  11. Numerical studies of pair creation in counterpropagating laser fields

    Energy Technology Data Exchange (ETDEWEB)

    Ruf, Matthias

    2009-05-27

    Pair creation from vacuum induced by electromagnetic fields is probably one of the most intriguing phenomena in physics. If the fields are sufficiently strong, the QED vacuum become unstable. Due to the remarkable progress in laser technology during recent years an experimental investigation of pair creation by pure laser light is coming into reach. The focus of this thesis is on pair creation in counterpropagating laser beams. The pair creation probability is calculated employing the numerically obtained solutions of the Dirac equation. This numerical ansatz has the capability of calculating the momentum distribution of the created pairs in a single propagation, for pure time dependent field configurations. Furthermore, it allows to take the magnetic component of the laser fields into account, which is usually neglected. The latter strongly affects the creation process at high laser frequency. The involved numerical calculations are rather time consuming, therefore the second project of this thesis was to develop a highly efficient code for solving relativistic quantum mechanical problems. This is accomplished by adopting the split-operator method to the Klein-Gordon equation. Here the possibility arises to use parallel computing. However the corresponding spin-statistics becomes crucial in the case of pair creation, demonstrated in several examples. (orig.)

  12. Numerical studies of pair creation in counterpropagating laser fields

    Energy Technology Data Exchange (ETDEWEB)

    Ruf, Matthias

    2009-05-27

    Pair creation from vacuum induced by electromagnetic fields is probably one of the most intriguing phenomena in physics. If the fields are sufficiently strong, the QED vacuum become unstable. Due to the remarkable progress in laser technology during recent years an experimental investigation of pair creation by pure laser light is coming into reach. The focus of this thesis is on pair creation in counterpropagating laser beams. The pair creation probability is calculated employing the numerically obtained solutions of the Dirac equation. This numerical ansatz has the capability of calculating the momentum distribution of the created pairs in a single propagation, for pure time dependent field configurations. Furthermore, it allows to take the magnetic component of the laser fields into account, which is usually neglected. The latter strongly affects the creation process at high laser frequency. The involved numerical calculations are rather time consuming, therefore the second project of this thesis was to develop a highly efficient code for solving relativistic quantum mechanical problems. This is accomplished by adopting the split-operator method to the Klein-Gordon equation. Here the possibility arises to use parallel computing. However the corresponding spin-statistics becomes crucial in the case of pair creation, demonstrated in several examples. (orig.)

  13. A Social Vision for Value Co-creation in Design

    Directory of Open Access Journals (Sweden)

    George Simons

    2009-11-01

    Full Text Available The Cluetrain Manifesto was introduced in 1999, calling for a powerful global conversation between companies and the people they serve. Since then, the conversation has started and is finally gaining momentum. Co-creation is the buzzword of the day to describe the various types of conversations that are taking place. But the conversation has multiple perspectives. It can be applied to multiple domains ranging from sales tactics and branding contests to strategic, human-centered means of affecting social transformation. In this article we try to articulate a vision for value co-creation by focusing on its social aspects. It is our hope that such social vision will contribute to existing perspectives so that future conversations can take place in a more productive way. The suggested framework organizes the seemingly disparate applications, comparing the mindset, goals and results of three types of value co-creation: monetary, use/experience and social. Although these three types of value co-creation are all relevant, we believe that the social type of value provides a real opportunity for significant social change. However, the rules of engagement for this type of co-creation are particularly challenging. Participation must be face-to-face to allow for real-time interaction to take place. Empathy for the people who will be affected by change is key. Visualization of the collective assets is essential. And having the appropriate mindset about co-creation is the single most important component for success.

  14. Toward the philosophy of creation: Maximus the confessor

    Directory of Open Access Journals (Sweden)

    Cvetković Vladimir

    2011-01-01

    Full Text Available The article aims to present the philosophical argumentation in favor of the Christian idea of the creation of the world exposed in the work of the seventh century author Maximus the Confessor. Maximus the Confessor developed his doctrine of creation on the basis of the philosophical arguments of his Christian predecessors, above all, Gregory of Nyssa, Nemesius of Emesa and Dionysius the Areopagite. The core of Maximus’ argumentation on the creation of the world is similar to the position of the Alexandrian philosopher John Philoponus (6th century, but it is additionally enriched with ideas deriving from the works of the aforementioned Christian authors. Some of the ideas that form the scaffolding of Maximus’ doctrine of creation are: the fivefold division of beings, which has its climax in the division between the created and uncreated nature, the movement of creatures towards God, who alone is the true goal of their movement, the eternal existence of the world in logoi as expressions of divine will, God’s providential care not only for the universal but also for the individual beings and the deification of the entire created world as the initial purpose of creation. Maximus’ views on creation are conveyed in a language that combines Aristotelian, Stoic and Neoplatonist philosophical vocabulary.

  15. Stakeholder Theory and Value Creation Models in Brazilian Firms

    Directory of Open Access Journals (Sweden)

    Natalia Giugni Vidal

    2015-09-01

    Full Text Available Objective – The purpose of this study is to understand how top Brazilian firms think about and communicate value creation to their stakeholders. Design/methodology/approach – We use qualitative content analysis methodology to analyze the sustainability or annual integrated reports of the top 25 Brazilian firms by sales revenue. Findings – Based on our analysis, these firms were classified into three main types of stakeholder value creation models: narrow, broad, or transitioning from narrow to broad. We find that many of the firms in our sample are in a transition state between narrow and broad stakeholder value creation models. We also identify seven areas of concentration discussed by firms in creating value for stakeholders: better stakeholder relationships, better work environment, environmental preservation, increased customer base, local development, reputation, and stakeholder dialogue. Practical implications – This study shows a trend towards broader stakeholder value creation models in Brazilian firms. The findings of this study may inform practitioners interested in broadening their value creation models. Originality/value – This study adds to the discussion of stakeholder theory in the Brazilian context by understanding variations in value creation orientation in Brazil.

  16. Numerical Modeling of Plasma Actuators for Flow Control

    OpenAIRE

    KOURTZANIDIS, Konstantinos

    2014-01-01

    As aerodynamic flow control still remains one of the top subjects of research in the aerospace scientific world, new ways to perform such a control are being constantly studied. Microwave plasma discharges have been proposed as a mean of a non-intrusive flow control method based on the creation of hot spots of air (via the creation of plasma discharges) which can eventually interact with the external flow and modify its attributes in a beneficial way to the aerodynamic coefficients of the body of i...

  17. Development of a Thermal Desorption Gas Chromatography-Mass Spectrometry Analysis Method for Airborne Dichlorodiphenyltrichloroethane

    Science.gov (United States)

    2013-05-28

    capable of taking a blood meal, require protein from blood for egg laying. The selection of where to lay eggs is highly variable, but Anopheles and Aedes...chemist Paul Hermann Müeller discovered DDT’s insecticidal activity, a finding that earned him the 1948 Nobel Prize for Medicine and Physiology “for his...Ecological Connections:65-9 23. Frierson JG. 2010. The yellow fever vaccine: a history . Yale J Biol Med 83:77-85 24. Galadi A, Bitar H, Chanon M

  18. Thermal desorption of deuterium from Be, and Be with helium bubbles

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, A.V.; Van Veen, A.; Busker, G.J. [Delft Univ. of Technology (Netherlands). Interfaculty Reactor Inst.

    1998-01-01

    Deuterium desorption measurements carried out on a single-crystalline beryllium sample are presented. Deuterium ions were implanted at room temperature at the energy of 0.7 and 1.2 keV up to doses ranging from 10{sup 19} to 3.6 x 10{sup 21} m{sup -2}. In order to eliminate the influence of the beryllium-oxide surface layer, before the implantation the surface of the sample was cleaned by argon sputtering. After the implantation the sample was annealed up to 1200 K at a constant rate of 10 K/s. Deuterium released from the sample was monitored by a calibrated quadrupole mass-spectrometer. The desorption spectra revealed two different contributions. One is a well defined and very narrow peak centered around 450 K. This peak is observed only at high implantation doses > 7.8 x 10{sup 20} m{sup -2}, which is close to the deuterium saturation limit of 0.3 D/Be and is related to deuterium release from blisters or interconnected bubbles. The activation energy of 1.1 eV and the threshold implantation dose are consistent with the values reported in literature. The second contribution in the release spectra is found in the temperature range from 600 to 900 K and is present throughout the whole range of the implantation doses. The activation energies corresponding to this release lie in the range between 1.8 and 2.5 eV and are ascribed to the release from deuterium-vacancy type of defects. In a number of experiments the deuterium implantation was preceded by helium implantation followed by partial annealing to create helium bubbles. The resulting deuterium desorption spectra indicate that deuterium detrapping from helium bubbles is characterized by an activation energy of 2.7 eV. (author)

  19. Diffusive uptake in passive and active adsorbent sampling using thermal desorption tubes.

    Science.gov (United States)

    Batterman, Stuart; Metts, Tricia; Kalliokoski, Pentti

    2002-12-01

    Low flow active sampling techniques collecting vapors and gases using thermally desorbable adsorbents are now feasible and desirable in many applications as they permit long integration times, the potential for miniaturized sampling configurations, and other advantages. At very low air flow rates (estimates of the tortuosity and porosity of the glass wool packing used to retain the adsorbent, parameters needed to estimate diffusive fluxes in passive and active sampling; (4) a demonstration that orifice-equipped low flow active samplers can reduce diffusive uptake and improve precision, and (5) a model predicting the saturated adsorbent layer that helps to account for the gradual decline in uptake rates seen in passive sampling. Diffusive uptake will depend on the tube configuration and diffusion coefficient of the substance of interest, but for conventional sampling tubes (0.4-0.5 cm id, 1.5 cm air gap), sample flow rates should be maintained above 1 to 4 ml min(-1) to keep errors below 5%. Laboratory experiments showed close agreement with theoretical calculations, and the field study using 1 to 4 d sampling periods and 0.3 ml min(-1) flows demonstrated that the orifice-equipped samplers essentially eliminated diffusive uptake. No significant practical difficulties are encountered using orifices, e.g., pressure drop is minimal. Experimental estimates of tortuosity (0.79 +/- 0.02) and porosity (0.92 +/- 0.10) of the glass wool packing (0.3 cm length) represent relatively little resistance to diffusion; however, variation in the packing and adsorbent placement can degrade the precision achievable by passive samplers. Diffusion barriers, consisting most simply of an orifice, may be used to lower the diffusive uptake. A needle-type orifice permits flows below 0.1 ml min(-1) and is suitable for sampling periods as long as several weeks, and it provided greater precision than conventional open-ended sampling tubes (8% compared to 13%). Finally, the gradual decrease in diffusive fluxes often seen in passive sampling is attributed to additional resistance posed by a saturated adsorbent layer, in agreement with a simple model based on total VOCs and specific adsorptivity of the adsorbent.

  20. Thermal desorption solid-phase microextraction inlet for differential mobility spectrometry.

    Science.gov (United States)

    Rainsberg, Matthew R; de Harrington, Peter B

    2005-06-01

    A splitless thermal desorber unit that interfaces a differential mobility spectrometry (DMS) sensor has been devised. This device was characterized by the detection of benzene, toluene, and xylene (BTX) in water. The detection of BTX in water is important for environmental monitoring, and ion mobility measurements are traditionally difficult for hydrocarbons in water because water competes for charge and quenches the hydrocarbon signals. This paper reports the use of a DMS with a photoionization source that is directly coupled to a solid-phase microextraction (SPME) desorber. The separation and detection capabilities of the DMS were demonstrated using BTX components. Detection limits for benzene, toluene, and m-xylene were 75, 50, and 5 microg mL(-1), respectively.

  1. Analysis of Thermal Desorption System for the Chemical Treatment of Old Storages of Oil Based Mud

    Directory of Open Access Journals (Sweden)

    Tanweer Hussain

    2013-04-01

    Full Text Available This paper presents an analysis for the chemical treatment of OBM (Oil Based Mud used in the drilling process in the oil and gas industry. The analysis is based on OBM stored at ENI (Italian National Energy gas fields at Bhit mount district Jamshoro since the last ten years that has been chemically and physically deteriorated. Characterization of various OBM samples was performed and these samples were processed in order to evaluate the best characteristics of the OBM for optimum treatment results. The OBM treatment process involves the separation of hazardous fluid (such as diesel or mineral oil from solids Due to the lean quality of the OBM, the dust separation process in the cyclone caused blockage in the cyclone. This paper suggests a remedial way by means of installation of a hammer stick in the cyclone dust collector to overcome cyclone blockage. The analysis is performed to compare the pressure drop and the dust collection efficiency in the cyclone with and without the hammer stick. The post-installation experimental results showed that hammer stick can improve the cyclone dust collection efficiency without blockage of the cyclone.

  2. Analysis of Thermal Desorption System for the Chemical Treatment of Old Storages of Oil Based Mud

    OpenAIRE

    Tanweer Hussain; Abdul Rehman Memon; Javed Larik

    2013-01-01

    This paper presents an analysis for the chemical treatment of OBM (Oil Based Mud) used in the drilling process in the oil and gas industry. The analysis is based on OBM stored at ENI (Italian National Energy) gas fields at Bhit mount district Jamshoro since the last ten years that has been chemically and physically deteriorated. Characterization of various OBM samples was performed and these samples were processed in order to evaluate the best characteristics of the OBM for optimum treatment ...

  3. Annealing Behaviour of Helium Bubbles in Titanium Films by Thermal Desorption Spectroscopy and Positron Beam Analysis

    Institute of Scientific and Technical Information of China (English)

    LIU Chao-Zhuo; ZHOU Zhu-Ying; SHI Li-Qun; WANG Bao-Yi; HAO Xiao-Peng; ZHAO Guo-Qing

    2007-01-01

    @@ Helium-containing Ti films are prepared using magnetron sputtering in the helium-argon atmosphere. Isochronal annealing at different temperatures for an hour is employed to reveal the behaviour of helium bubble growth. Ion beam analysis is used to measure the retained helium content. Helium can release largely when annealing above 970 K. A thermal helium desorption spectroscopy system is constructed for assessment of the evolution of helium bubbles in the annealed samples by linear heating (0.4K/s) from room temperature to 1500K. Also, Doppler broadening measurements of positron annihilation radiation spectrum are performed by using changeable energy positron beam. Bubble coarsening evolves gradually below 680K, migration and coalescence of small bubbles dominates in the range of 680-970K, and the Ostwald ripening mechanism enlarges the bubbles with a massive release above 970K.

  4. Spatial distributions and transient effects in molecular fluxes for the calibration of thermal desorption spectrometers

    Science.gov (United States)

    Jackson, Robert Howard

    The measurement of molecular fluxes with a differentially pumped mass spectrometer requires a method by which the mass spectrometer signal can be calibrated against a known molecular flux. This work presents a methodology for producing known molecular fluxes using a flow calibrated effusion source in conjunction with a glass capillary array molecular doser. The effusion source is comprised of a calibrated volume, a spinning rotor pressure gauge, and a positive shutoff capillary leak valve. The efficiency of calculating the spatial flux distribution from the doser was improved by reparameterization of the formalism of Winkler and Yates. This formalism was extended to arbitrarily shaped planar targets using Fourier convolution techniques. The flux distribution from the doser was measured close to the array at 0.635mm and at 1 cm distance. Using the effective diameter of the array as the only fitting parameter for the close data, the model correctly predicts the flux distribution at 1 cm. The loss of molecular flow due to sticking in the doser affects the calibration and, therefore was estimated from the transient response through the doser using a 1-dimensional diffusion model of the transient flow from the capillary valve through the doser. Three cases are considered: a long narrow tube without sticking, with sticking, and with a restricted exit. In each case, the partial differential equation for 1-D diffusion was solved for a step change in the inlet flow with a well-pumped exit. The transient exit flow measured for argon gas fits the non-sticking model accurately. The oxygen response included a non-sticking transient, consistent with the mass adjusted argon transient, and a slowly saturating exponential function. This slow function is not consistent with sticking in the doser tube but may be due to changes in the mass spectrometer multiplier or some other adsorption loss. Finally, the above methodology was used to calibrate the mass spectrometer for oxygen and the c(2 x 4) oxygen coverage on Pd(110) was measured to be 0.44MIL, consistent with measurements by nuclear reaction analysis. A modified King-Wells method for adsorption is also presented but shows an adsorbed coverage 30% lower than that previously measured.

  5. The thermal desorption of CO2 from amine carbamate solutions for the 13C isotope enrichment

    Science.gov (United States)

    Dronca, S.; Varodi, C.; Gligan, M.; Stoia, V.; Baldea, A.; Hodor, I.

    2012-02-01

    The CO2 desorption from amine carbamate in non-aqueous solvents is of major importance for isotopic enrichment of 13C. A series of experiments were carried out in order to set up the conditions for the CO2 desorption. For this purpose, a laboratory- scale plant for 13C isotope separation by chemical exchange between CO2 and amine carbamate was designed and used. The decomposition of the carbamate solution was mostly produced in the desorber and completed in the boiler. Two different-length desorbers were used, at different temperatures and liquid flow rates of the amine-non-aqueous solvent solutions. The residual CO2 was determined by using volumetric and gaschromatographic methods. These results can be used for enrichment of 13C by chemical exchange between CO2 and amine carbamate in nonaqueous solvents.

  6. Determination of trace organic impurities in water using thermal desorption from XAD resin

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, J.P.; Fritz, J.S.

    1978-10-01

    A small water sample (20 to 250 ml) is passed through a small tube containing XAD-4 resin; this effectively retains the organic impurities present in the water. This tube is connected to the permanent apparatus and the sorbed organics are thermally transferred to a small Tenex pre-column while the water vapor is vented. The pre-column is closed off, preheated to 275 to 280/sup 0/C, and then a valve is opened to plug-inject the vaporized sample into a gas chromatograph. The procedure works well for a variety of model organic compounds added to water and can be used for the analysis of actual water samples.

  7. Contextual-Based Knowledge Creation for Agroindustrial Innovation

    Directory of Open Access Journals (Sweden)

    Elisa Anggraeni

    2017-08-01

    Full Text Available This paper discusses the knowledge creation process in one department, in a higher educational context, and the possible actions to take to improve the efficiency and effectiveness of the knowledge creation system in it. We conducted a case study at one department of a university that strives to improve its innovations, in terms of their quantity and quality.We used a soft system methodology to investigate the knowledge creation system in the chosen department. From the study, we conclude that the department can be considered as a learning organization, within which its staff continually create, acquire and transfer knowledge. This department has a learning environment which is conducive, concrete learning processes, and leadership that reinforces learning. In the context of producing agroindustry innovations, the knowledge creation system in this department is considered to be less effective since it frequently happens more at individual or small group levels. To improve its effectiveness, the management may facilitate the institutionalization of knowledge creation processes at every phase of the interactions between tacit and explicit knowledge.

  8. Mobile, Collaborative Situated Knowledge Creation for Urban Planning

    Directory of Open Access Journals (Sweden)

    Nelson Baloian

    2012-05-01

    Full Text Available Geo-collaboration is an emerging research area in computer sciences studying the way spatial, geographically referenced information and communication technologies can support collaborative activities. Scenarios in which information associated to its physical location are of paramount importance are often referred as Situated Knowledge Creation scenarios. To date there are few computer systems supporting knowledge creation that explicitly incorporate physical context as part of the knowledge being managed in mobile face-to-face scenarios. This work presents a collaborative software application supporting visually-geo-referenced knowledge creation in mobile working scenarios while the users are interacting face-to-face. The system allows to manage data information associated to specific physical locations for knowledge creation processes in the field, such as urban planning, identifying specific physical locations, territorial management, etc.; using Tablet-PCs and GPS in order to geo-reference data and information. It presents a model for developing mobile applications supporting situated knowledge creation in the field, introducing the requirements for such an application and the functionalities it should have in order to fulfill them. The paper also presents the results of utility and usability evaluations.

  9. Organizational Knowledge Conversion and Creation Processes in a Chaotic Environment

    Directory of Open Access Journals (Sweden)

    Andrei Ștefan NESTIAN

    2013-05-01

    Full Text Available This is an explorative and conceptual paper, based on the analysis and comparison of relevant literature. the purpose of the article is to clarify the differences between knowledge creating processes and knowledge conversion processes, by analysing them when confronted with a chaotic environment. the way the knowledge conversion and creation processes are presented by Ikujiro Nonaka and his co-workers suggests the necessary existence of a Ba in order to generate the spiral of knowledge creation. this implies the acceptance of a relationship between the environment and the knowledge conversion process, in which the environment influences the knowledge creation. the article is based on the hypothesis that a chaotic environment, characterized by unpredictability, non-linearity and crisis, will lead to specific ways of functioning of the knowledge creation and conversion process that highlight the relations between the two different types of processes. Starting from the general concept of resilience, herein one proposes and explains the concept of resilience of the knowledge conversion system. the role of the attractors from the chaotic environment in the creation of new knowledge is identified and explained

  10. Evolution and dynamics of a matter creation model

    Science.gov (United States)

    Pan, S.; Haro, J. de; Paliathanasis, A.; Slagter, R. J.

    2016-08-01

    In a flat Friedmann-Lemaître-Robertson-Walker (FLRW) geometry, we consider the expansion of the universe powered by the gravitationally induced `adiabatic' matter creation. To demonstrate how matter creation works well with the expanding universe, we have considered a general creation rate and analysed this rate in the framework of dynamical analysis. The dynamical analysis hints the presence of a non-singular universe (without the big bang singularity) with two successive accelerated phases, one at the very early phase of the universe (i.e. inflation), and the other one describes the current accelerating universe, where this early, late accelerated phases are associated with an unstable fixed point (i.e. repeller) and a stable fixed point (attractor), respectively. We have described this phenomena by analytic solutions of the Hubble function and the scale factor of the FLRW universe. Using Jacobi last multiplier method, we have found a Lagrangian for this matter creation rate describing this scenario of the universe. To match with our early physics results, we introduce an equivalent dynamics driven by a single scalar field, discuss the associated observable parameters and compare them with the latest Planck data sets. Finally, introducing the teleparallel modified gravity, we have established an equivalent gravitational theory in the framework of matter creation.

  11. Pin Hole Discharge Creation in Na2SO4 Water Solutions

    Directory of Open Access Journals (Sweden)

    Lucie Hlavatá

    2013-01-01

    Full Text Available This work deals with the diaphragm discharge generated in water solutions containing Na2SO4 as a supporting electrolyte. The solution conductivity was varied in the range of 270 ÷ 750 µScm-1. The batch plasma reactor with volume of 100 ml was divided into two electrode spaces by the Shapal-MTM ceramics dielectric barrier with a pin-hole (diameter of 0.6 mm. Three variable barrier thicknesses (0.3; 0.7 and 1.5 mm and non-pulsed DC voltage up to 2 kV were used for the discharge creation. Each of the current–voltage characteristic can be divided into three parts: electrolysis, bubble formation and discharge operation. The experimental results showed that the discharge ignition moment in the pin-hole was significantly dependent on the dielectric diaphragm thickness. Breakdown voltage increases with the increase of the dielectric barrier thickness.

  12. Spatially dependent electron-positron pair creation rate

    Science.gov (United States)

    Lv, Q. Z.; Unger, J.; Li, Y. T.; Su, Q.; Grobe, R.

    2016-11-01

    The vacuum breakdown process in an inhomogeneous supercritical electric field of finite extension is examined. By probing the electron-positron pair creation zone with incoming electrons that have controlled velocities, we can address the fundamental question of where the electrons are being created from the vacuum. In contrast to what one might expect, the spatial regions of most likely pair creation are not necessarily those where the electric-field strength is largest. In fact, the creation regions are determined solely by energetic considerations and particles can therefore be created in spatial regions where the local field strength is far below the Schwinger threshold. These predictions are also supported independently by spatial probability densities obtained by extrapolation as well as by classical and quantum-mechanical analysis.

  13. Generalized creation and annihilation operators via complex nonlinear Riccati equations

    Science.gov (United States)

    Schuch, Dieter; Castaños, Octavio; Rosas-Ortiz, Oscar

    2013-06-01

    Based on Gaussian wave packet solutions of the time-dependent Schrödinger equation, a generalization of the conventional creation and annihilation operators and the corresponding coherent states can be obtained. This generalization includes systems where also the width of the coherent states is time-dependent as they occur for harmonic oscillators with time-dependent frequency or systems in contact with a dissipative environment. The key point is the replacement of the frequency ω0 that occurs in the usual definition of the creation/annihilation operator by a complex time-dependent function that fulfils a nonlinear Riccati equation. This equation and its solutions depend on the system under consideration and on the (complex) initial conditions. Formal similarities also exist with supersymmetric quantum mechanics. The generalized creation and annihilation operators also allow to construct exact analytic solutions of the free motion Schrödinger equation in terms of Hermite polynomials with time-dependent variable.

  14. Enhanced creation of high energy particles in colliding laser beams

    CERN Document Server

    Kuchiev, Michael

    2015-01-01

    The creation of particles by two colliding strong laser beams is considered. It is found that the electron-positron pairs created in the laser field via the Schwinger mechanism may recollide after one or several oscillations in the field. Their collision can take place at high energy, which the pair gains from the field. As a result, high energy gamma quanta can be created by inelastic scattering or annihilation of the pair. Moreover, heavy particles such as muon pairs may also be created via the annihilation $e^+ + e^-\\rightarrow \\mu^+ + \\mu^- $. The probability of $e^-e^+$ collision is greatly enhanced due to a strong alignment of the electron and positron momenta with the electric field. The found muon creation rate exponentially exceeds the rate predicted by the direct Schwinger mechanism for muons, while the photon creation rate exponentially exceeds photon emission due to the fermion oscillation.

  15. The cost of wetland creation and restoration. Final report

    Energy Technology Data Exchange (ETDEWEB)

    King, D.; Bohlen, C.

    1995-08-01

    This report examines the economics of wetland creation, restoration, and enhancement projects, especially as they are used within the context of mitigation for unavoidable wetland losses. Complete engineering-cost-accounting profiles of over 90 wetland projects were developed in collaboration with leading wetland restoration and creation practitioners around the country to develop a primary source database. Data on the costs of over 1,000 wetland projects were gathered from published sources and other available databases to develop a secondary source database. Cases in both databases were carefully analyzed and a set of baseline cost per acre estimates were developed for wetland creation, restoration, and enhancement. Observations of costs varied widely, ranging from $5 per acre to $1.5 million per acre. Differences in cost were related to the target wetland type, and to site-specific and project-specific factors that affected the preconstruction, construction, and post-construction tasks necessary to carry out each particular project. Project-specific and site-specific factors had a much larger effect on project costs than wetland type for non-agricultural projects. Costs of wetland creation and restoration were also shown to differ by region, but not by as much as expected, and in response to the regulatory context. The costs of wetland creation, restoration, and enhancement were also analyzed in a broader economic context through examination of the market for wetland mitigation services, and through the development of a framework for estimating compensation ratios-the number of acres of created, restored, or enhanced wetland required to compensate for an acre of lost natural wetland. The combination of per acre creation, restoration, and enhancement costs and the compensation ratio determine the overall mitigation costs associated with alternative mitigation strategies.

  16. Some problems of pulsar physics. [magnetospheric plasma model

    Science.gov (United States)

    Arons, J.

    1979-01-01

    The theories of particle acceleration along polar field lines are reviewed, and the total energization of the charge separated plasma is summarized, when pair creation is absent. The application of these theories and plasma supply to pulsars is discussed, with attention given to the total amount of electron-positron plasma created and its momentum distribution. Various aspects of radiation emission and transport are analyzed, based on a polar current flow model with pair creation, and the phenomenon of marching subpulses is considered. The coronation beaming and the relativistically expanding current sheet models for pulsar emission are also outlined, and the paper concludes with a brief discussion of the relation between the theories of polar flow with pair plasma and the problem of the energization of the Crab Nebula.

  17. Creation of a small high-throughput screening facility.

    Science.gov (United States)

    Flak, Tod

    2009-01-01

    The creation of a high-throughput screening facility within an organization is a difficult task, requiring a substantial investment of time, money, and organizational effort. Major issues to consider include the selection of equipment, the establishment of data analysis methodologies, and the formation of a group having the necessary competencies. If done properly, it is possible to build a screening system in incremental steps, adding new pieces of equipment and data analysis modules as the need grows. Based upon our experience with the creation of a small screening service, we present some guidelines to consider in planning a screening facility.

  18. Designer Modeling for Personalized Game Content Creation Tools

    DEFF Research Database (Denmark)

    Liapis, Antonios; Yannakakis, Georgios N.; Togelius, Julian

    2013-01-01

    With the growing use of automated content creation and computer-aided design tools in game development, there is potential for enhancing the design process through personalized interactions between the software and the game developer. This paper proposes designer modeling for capturing the designer......’s preferences, goals and processes from their interaction with a computer-aided design tool, and suggests methods and domains within game development where such a model can be applied. We describe how designer modeling could be integrated with current work on automated and mixed-initiative content creation...

  19. Successful femtosecond LASIK flap creation despite multiple suction losses

    Science.gov (United States)

    Syed, Zeba A.; Melki, Samir A.

    2014-01-01

    Summary We present a case of successful completion of a laser in situ keratomileusis (LASIK) procedure despite 5 episodes of suction loss during femtosecond flap creation in a 30-year-old man with no risk factors. The patient had an uncorrected distance visual acuity of 20/20 in both eyes at his 2-month follow-up visit. Our experience in this case shows that multiple suction losses during femtosecond LASIK flap creation do not preclude completion of a successful procedure with excellent visual outcomes. Caution and technique modification are advised if multiple laser passes are applied to avoid creating multiplanar flaps. PMID:25097457

  20. Creation of Entangled Universes Avoids the Big Bang Singularity

    Directory of Open Access Journals (Sweden)

    Salvador J. Robles-Pérez

    2014-01-01

    Full Text Available The creation of universes in entangled pairs may avoid the initial singularity and it would have observable consequences in a large macroscopic universe like ours, at least in principle. In this paper we describe the creation of an entangled pair of universes from a double instanton, which avoids the initial singularity, in the case of a homogeneous and isotropic universe with a conformally coupled massless scalar field. The thermodynamical properties of interuniversal entanglement might have observable consequences on the properties of our single universe provided that the thermodynamics of entanglement is eventually related to the classical formulation of thermodynamics.