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Sample records for characterize sources andpathways

  1. Merging Models and Biomonitoring Data to Characterize Sources andPathways of Human Exposure to Organophosphorous Pesticides in the SalinasValley of California

    Energy Technology Data Exchange (ETDEWEB)

    McKone, Thomas E.; Castorina, Rosemary; Kuwabara, Yu; Harnly,Martha E.; Eskenazi, Brenda; Bradman, Asa

    2006-06-01

    By drawing on human biomonitoring data and limited environmental samples together with outputs from the CalTOX multimedia, multipathway source-to-dose model, we characterize cumulative intake of organophosphorous (OP) pesticides in an agricultural region of California. We assemble regional OP pesticide use, environmental sampling, and biological tissue monitoring data for a large and geographically dispersed population cohort of 592 pregnant Latina women in California (the CHAMACOS cohort). We then use CalTOX with regional pesticide usage data to estimate the magnitude and uncertainty of exposure and intake from local sources. We combine model estimates of intake from local sources with food intake based on national residue data to estimate for the CHAMACOS cohort cumulative median OP intake, which corresponds to expected levels of urinary dialkylphosphate (DAP) metabolite excretion for this cohort. From these results we develop premises about relative contributions from different sources and pathways of exposure. We evaluate these premises by comparing the magnitude and variation of DAPs in the CHAMACOS cohort with the whole U.S. population using data from the National Health and Nutrition Evaluation Survey (NHANES). This comparison supports the premise that in both populations diet is the common and dominant exposure pathway. Both the model results and biomarker comparison supports the observation that the CHAMACOS population has a statistically significant higher intake of OP pesticides that appears as an almost constant additional dose among all participants. We attribute the magnitude and small variance of this intake to non-dietary exposure in residences from local sources.

  2. Aero particles characterization emitted by mobile sources

    International Nuclear Information System (INIS)

    In our country, the mobile sources that conform most of the emissions at the atmosphere, are concentrated on the urban areas. For the present work, samples coming from the escapes of terrestrial transport were obtained, such as: passenger buses, load transport and particular vehicles of the Metropolitan area of the Toluca valley. The material was analyzed by means of scanning electron microscopy of low vacuum and X-ray diffraction. The objective was to characterize the emitted particles by mobile sources, morphological and chemically to know the structure, size and elements that compose them. (Author)

  3. Characterization of coherent Cherenkov radiation source

    Energy Technology Data Exchange (ETDEWEB)

    Smirnov, A.V.

    2015-01-21

    Engineering formulae for calculation of peak, and spectral brightness of resonant long-range wakefield extractor are given. It is shown that the brightness is dominated by beam density in the slow wave structure and antenna gain of the outcoupling. Far field radiation patterns and brightness of circular and high aspect ratio planar radiators are compared. A possibility to approach diffraction limited brightness is demonstrated. The role of group velocity in designing of the Cherenkov source is analyzed. The approach can be applied for design and characterization of various structure-dominated sources (e.g., wakefield extractors with gratings or dielectrics, or FEL-Cherenkov combined sources) radiating into a free space using an antenna (in microwave to sub-mm wave regions). The high group velocity structures can be also effective as energy dechirpers and for diagnostics of microbunched relativistic electron beams.

  4. Natural proteins: Sources, isolation, characterization and applications

    Directory of Open Access Journals (Sweden)

    Jitendra Y Nehete

    2013-01-01

    Full Text Available Worldwide, plant protein contributes substantially as a food resource because it contains essential amino acids for meeting human physiological requirements. However, many versatile plant proteins are used as medicinal agents as they are produced by using molecular tools of biotechnology. Proteins can be obtained from plants, animals and microorganism cells. The abundant economical proteins can be obtained from plant seeds. These natural proteins are obtained by isolation procedures depending on the physicochemical properties of proteins. Isolation and purification of single protein from cells containing mixtures of unrelated proteins is achievable due to the physical and chemical attributes of proteins. The following characteristics are unique to each protein: Amino acid composition, sequence, subunit structures, size, shape, net charge, isoelectric point, solubility, heat stability and hydrophobicity. Based on these properties, various methods of isolation exist, like salting out and isoionic precipitation. Purification of proteins is quiet challenging and, therefore, several approaches like sodium dodecyl sulfate gel electrophoresis and chromatography are available. Characterization of proteins can be performed by mass spectrometry/liquid chromatography-mass spectrometry (LC-MS. The amino acid sequence of a protein can be detected by using tandem mass spectrometry. In this article, a review has been made on the sources, isolation, purification and characterization of natural proteins.

  5. Characterizing the source of radon indoors

    International Nuclear Information System (INIS)

    Average indoor radon concentrations range over more than two orders of magnitude, largely because of variability in the rate at which radon enters from building materials, soil, and water supplies. Determining the indoor source magnitude requires knowledge of the generation of radon in source materials, its movement within materials by diffusion and convection, and the means of its entry into buildings. This paper reviews the state of understanding of indoor radon sources and transport. Our understanding of generation rates in and movement through building materials is relatively complete and indicates that, except for materials with unusually high radionuclide contents, these sources can account for observed indoor radon concentrations only at the low end of the range observed. Our understanding of how radon enters buildings from surrounding soil is poorer, however recent experimental and theoretical studies suggest that soil may be the predominant source in many cases where the indoor radon concentration is high. 73 references, 3 figures, 1 table

  6. Characterization of ISOLDE ion source and ion source chemistry

    CERN Document Server

    Barbeau, Marion

    2014-01-01

    This report presents results of measurements made with the ISOLDE OFF-LINE mass separator [1]. The first part shows measurements of the ionization characteristics of noble gases in a VADIS ion source. The goal of the measurements was to determine the dependency of the extractable current of first and second noble gases ions with the electron energy. In the second part, investigation on in-target chemistry are presented. Here, the effect of injected sulfur hexafluoride ($SF_6$) on the release of oxygen from aluminium oxide ($Al_2 O_3$) was studied.

  7. Characterizing Acoustic Sources in Pressure Vessels

    Institute of Scientific and Technical Information of China (English)

    李路明; 郑鹏; 刘时风; 施克仁

    2002-01-01

    The "dream" of acoustic emission (AE) testing is to get the acoustic source characteristics from AE signals, especially when evaluating aging pressure vessels. In this paper, the wavelet transform was used to analyze different AE signals from cracks (surface and inner), pencil-lead-breakage and leakage. These acoustic sources were applied on an actual pressure vessel. While the vessel experienced hydraulic pressure, their AE signals were acquired by a digital AE testing system with a wide frequency band transducer and a high speed A/D converter. Then, the digital signals were analyzed using the wavelet transform method. Correlation coefficients of the transformed data show that the different acoustic sources can be easily identified.

  8. Characterizing heralded single-photon sources with imperfect measurement devices

    Energy Technology Data Exchange (ETDEWEB)

    Razavi, M; Soellner, I; Bocquillon, E; Couteau, C; Laflamme, R; Weihs, G [Institute for Quantum Computing, University of Waterloo, 200 University Ave. W, Waterloo, ON N2L 3G1 (Canada)], E-mail: mrazavi@iqc.ca

    2009-06-14

    Any characterization of a single-photon source is not complete without specifying its second-order degree of coherence, i.e., its g{sup (2)} function. An accurate measurement of such coherence functions commonly requires high-precision single-photon detectors, in whose absence only time-averaged measurements are possible. It is not clear, however, how the resulting time-averaged quantities can be used to properly characterize the source. In this paper, we investigate this issue for a heralded source of single photons that relies on continuous-wave parametric down-conversion. By accounting for major shortcomings of the source and the detectors-i.e., the multiple-photon emissions of the source, the time resolution of photodetectors and our chosen width of coincidence window-our theory enables us to infer the true source properties from imperfect measurements. Our theoretical results are corroborated by an experimental demonstration using a PPKTP crystal pumped by a blue laser that results in a single-photon generation rate about 1.2 millions per second per milliwatt of pump power. This work takes an important step towards the standardization of such heralded single-photon sources.

  9. Pulsed electron source characterization with the modified three gradient method

    CERN Document Server

    Marghitu, S; Dinca, C; Marghitu, O

    2001-01-01

    Results from the Modified Three Gradient Method (MTGM), applied to a pulsed high intensity electron source, are presented. The MTGM makes possible the non-destructive determination of beam emittance in the space charge presence [1]. We apply the MTGM to an experimental system equipped with a Pierce convergent diode, working in pulse mode, and having a directly heated cathode as electron source. This choice was mainly motivated by the availability of an analytical characterization of this source type [2], as well as the extended use of the Pierce type sources in linear accelerators. The experimental data are processed with a numerical matching program, based on the K-V equation for an axially symmetric configuration [3], to determine the emittance and object cross-over position and diameter. The variation of these parameters is further investigated with respect to both electrical and constructive characteristics of the source: cathode heating current, extraction voltage, and cathode-anode distance.

  10. Overview of ion source characterization diagnostics in INTF

    Energy Technology Data Exchange (ETDEWEB)

    Bandyopadhyay, M., E-mail: mainak@iter-india.org; Sudhir, Dass; Bhuyan, M.; Tyagi, H.; Joshi, J.; Yadav, A.; Rotti, C.; Parmar, Deepak; Patel, H.; Pillai, S.; Chakraborty, A. [ITER-India, Institute for Plasma Research, A-29 GIDC, Sector-25, Gandhinagar, Gujarat 382016 (India); Soni, J. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382 428 (India)

    2016-02-15

    INdian Test Facility (INTF) is envisaged to characterize ITER diagnostic neutral beam system and to establish the functionality of its eight inductively coupled RF plasma driver based negative hydrogen ion source and its beamline components. The beam quality mainly depends on the ion source performance and therefore, its diagnostics plays an important role for its safe and optimized operation. A number of diagnostics are planned in INTF to characterize the ion source performance. Negative ions and its cesium contents in the source will be monitored by optical emission spectroscopy (OES) and cavity ring down spectroscopy. Plasma near the extraction region will be studied using standard electrostatic probes. The beam divergence and negative ion stripping losses are planned to be measured using Doppler shift spectroscopy. During initial phase of ion beam characterization, carbon fiber composite based infrared imaging diagnostics will be used. Safe operation of the beam will be ensured by using standard thermocouples and electrical voltage-current measurement sensors. A novel concept, based on plasma density dependent plasma impedance measurement using RF electrical impedance matching parameters to characterize the RF driver plasma, will be tested in INTF and will be validated with OES data. The paper will discuss about the overview of the complete INTF diagnostics including its present status of procurement, experimentation, interface with mechanical systems in INTF, and integration with INTF data acquisition and control systems.

  11. Overview of ion source characterization diagnostics in INTF

    Science.gov (United States)

    Bandyopadhyay, M.; Sudhir, Dass; Bhuyan, M.; Soni, J.; Tyagi, H.; Joshi, J.; Yadav, A.; Rotti, C.; Parmar, Deepak; Patel, H.; Pillai, S.; Chakraborty, A.

    2016-02-01

    INdian Test Facility (INTF) is envisaged to characterize ITER diagnostic neutral beam system and to establish the functionality of its eight inductively coupled RF plasma driver based negative hydrogen ion source and its beamline components. The beam quality mainly depends on the ion source performance and therefore, its diagnostics plays an important role for its safe and optimized operation. A number of diagnostics are planned in INTF to characterize the ion source performance. Negative ions and its cesium contents in the source will be monitored by optical emission spectroscopy (OES) and cavity ring down spectroscopy. Plasma near the extraction region will be studied using standard electrostatic probes. The beam divergence and negative ion stripping losses are planned to be measured using Doppler shift spectroscopy. During initial phase of ion beam characterization, carbon fiber composite based infrared imaging diagnostics will be used. Safe operation of the beam will be ensured by using standard thermocouples and electrical voltage-current measurement sensors. A novel concept, based on plasma density dependent plasma impedance measurement using RF electrical impedance matching parameters to characterize the RF driver plasma, will be tested in INTF and will be validated with OES data. The paper will discuss about the overview of the complete INTF diagnostics including its present status of procurement, experimentation, interface with mechanical systems in INTF, and integration with INTF data acquisition and control systems.

  12. Antenna array characterization via radio interferometry observation of astronomical sources

    CERN Document Server

    Colegate, T M; Hall, P J; Padhi, S K; Wayth, R B; de Vaate, J G Bij; Crosse, B; Emrich, D; Faulkner, A J; Hurley-Walker, N; Acedo, E de Lera; Juswardy, B; Razavi-Ghods, N; Tingay, S J; Williams, A

    2015-01-01

    We present an in-situ antenna characterization method and results for a "low-frequency" radio astronomy engineering prototype array, characterized over the 75-300 MHz frequency range. The presence of multiple cosmic radio sources, particularly the dominant Galactic noise, makes in-situ characterization at these frequencies challenging; however, it will be shown that high quality measurement is possible via radio interferometry techniques. This method is well-known in the radio astronomy community but seems less so in antenna measurement and wireless communications communities, although the measurement challenges involving multiple undesired sources in the antenna field-of-view bear some similarities. We discuss this approach and our results with the expectation that this principle may find greater application in related fields.

  13. Single photon source characterization with a superconducting single photon detector

    CERN Document Server

    Hadfield, R H; Miller, A J; Mirin, R P; Nam, S W; Schwall, R E; Stevens, M J; Gruber, Steven S.; Hadfield, Robert H.; Miller, Aaron J.; Mirin, Richard P.; Nam, Sae Woo; Schwall, Robert E.; Stevens, Martin J.

    2005-01-01

    Superconducting single photon detectors (SSPD) based on nanopatterned niobium nitride wires offer single photon counting at fast rates, low jitter, and low dark counts, from visible wavelengths well into the infrared. We demonstrate the first use of an SSPD, packaged in a commercial cryocooler, for single photon source characterization. The source is an optically pumped, microcavity-coupled InGaAs quantum dot, emitting single photons on demand at 902 nm. The SSPD replaces the second silicon Avalanche Photodiode (APD) in a Hanbury-Brown Twiss interferometer measurement of the source second-order correlation function, g (2) (tau). The detection efficiency of the superconducting detector system is >2 % (coupling losses included). The SSPD system electronics jitter is 170 ps, versus 550 ps for the APD unit, allowing the source spontaneous emission lifetime to be measured with improved resolution.

  14. Characterization of an atomic hydrogen source for charge exchange experiments

    Science.gov (United States)

    Leutenegger, M. A.; Beiersdorfer, P.; Betancourt-Martinez, G. L.; Brown, G. V.; Hell, N.; Kelley, R. L.; Kilbourne, C. A.; Magee, E. W.; Porter, F. S.

    2016-11-01

    We characterized the dissociation fraction of a thermal dissociation atomic hydrogen source by injecting the mixed atomic and molecular output of the source into an electron beam ion trap containing highly charged ions and recording the x-ray spectrum generated by charge exchange using a high-resolution x-ray calorimeter spectrometer. We exploit the fact that the charge exchange state-selective capture cross sections are very different for atomic and molecular hydrogen incident on the same ions, enabling a clear spectroscopic diagnostic of the neutral species.

  15. Characterization of Greater-Than-Class C sealed sources. Volume 2, Sealed source characterization and future production

    International Nuclear Information System (INIS)

    Sealed sources are small, relatively high-activity radioactive sources typically encapsulated in a metallic container. The activities can range from less than 1 mCi to over 1,000 Ci. They are used in a variety of industries and are commonly available. Many of the sources will be classified as Greater-Than-Class C low-level radioactive waste (GTCC LLW) for the purpose of waste disposal. The US Department of Energy is responsible for disposing of this class of low-level radioactive waste. The characterization of a sealed source is essentially a function of the type of radiation it emits, the principal use for which it is applied, and the activity it contains. The types of radiation of most interest to the GTCC LLW Program are gamma rays and neutrons, since these are emitted by the highest activity sources. The principal uses of most importance are gamma irradiators, medical teletherapy, well logging probes, and other general neutron applications. Current annual production rates of potential Greater-Than-Class C (PGTCC) sources sold to specific licensees were estimated based on data collected from device manufacturers. These estimates were then adjusted for current trends in the industry to estimate future annual production rates. It is expected that there will be approximately 8,000 PGTCC sealed sources produced annually for specific licensees

  16. Characterization of the radiation background at the Spallation Neutron Source

    Science.gov (United States)

    DiJulio, Douglas D.; Cherkashyna, Nataliia; Scherzinger, Julius; Khaplanov, Anton; Pfeiffer, Dorothea; Cooper-Jensen, Carsten P.; Fissum, Kevin G.; Kanaki, Kalliopi; Kirstein, Oliver; Ehlers, Georg; Gallmeier, Franz X.; Hornbach, Donald E.; Iverson, Erik B.; Newby, Robert J.; Hall-Wilton, Richard J.; Bentley, Phillip M.

    2016-09-01

    We present a survey of the radiation background at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory, TN, USA during routine daily operation. A broad range of detectors was used to characterize primarily the neutron and photon fields throughout the facility. These include a WENDI-2 extended range dosimeter, a thermoscientific NRD, an Arktis 4He detector, and a standard NaI photon detector. The information gathered from the detectors was used to map out the neutron dose rates throughout the facility and also the neutron dose rate and flux profiles of several different beamlines. The survey provides detailed information useful for developing future shielding concepts at spallation neutron sources, such as the European Spallation Source (ESS), currently under construction in Lund, Sweden.

  17. Characterization of Pu-238 Heat Source Granule Containment

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, Paul Dean II [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sanchez, Joey Leo [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wall, Angelique Dinorah [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chavarria, Rene [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-02-11

    The Milliwatt Radioisotopic Themoelectric Generator (RTG) provides power for permissive-action links. Essentially these are nuclear batteries that convert thermal energy to electrical energy using a doped silicon-germanium thermopile. The thermal energy is provided by a heat source made of 238Pu, in the form of 238PuO2 granules. The granules are contained by 3 layers of encapsulation. A thin T-111 liner surrounds the 238PuO2 granules and protects the second layer (strength member) from exposure to the fuel granules. An outer layer of Hastalloy-C protects the T-111 from oxygen embrittlement. The T-111 strength member is considered the critical component in this 238PuO2 containment system. Any compromise in the strength member seen during destructive testing required by the RTG surveillance program is characterized. The T-111 strength member is characterized through Scanning Electron Microscopy (SEM), and Metallography. SEM is used in the Secondary Electron mode to reveal possible grain boundary deformation and/or cracking in the region of the strength member weld. Deformation and cracking uncovered by SEM are further characterized by Metallography. Metallography sections are mounted and polished, observed using optical microscopy, then documented in the form of microphotographs. SEM mat further be used to examine polished Metallography mounts to characterize elements using the SEM mode of Energy Dispersive X-ray spectroscopy (EDS).

  18. Characterization of short-pulse laser driven neutron source

    Science.gov (United States)

    Falk, Katerina; Jung, Daniel; Guler, Nevzat; Deppert, Oliver; Devlin, Matthew; Fernandez, J. C.; Gautier, D. C.; Geissel, M.; Haight, R. C.; Hegelich, B. M.; Henzlova, Daniela; Ianakiev, K. D.; Iliev, Metodi; Johnson, R. P.; Merrill, F. E.; Schaumann, G.; Schoenberg, K.; Shimada, T.; Taddeucci, T. N.; Tybo, J. L.; Wagner, F.; Wender, S. A.; Wurden, G. A.; Favalli, Andrea; Roth, Markus

    2014-10-01

    We present a full spectral characterization of a novel laser driven neutron source, which employed the Break Out Afterburner ion acceleration mechanism. Neutrons were produced by nuclear reactions of the ions deposited on Be or Cu converters. We observed neutrons at energies up to 150 MeV. The neutron spectra were measured by five neutron time-of-flight detectors at various positions and distances from the source. The nTOF detectors observed that emission of neutrons is a superposition of an isotropic component peaking at 3.5--5 MeV resulting from nuclear reactions in the converter and a directional component at 25--70 MeV, which was a product of break-up reaction of the forward moving deuterons. Energy shifts due to geometrical effects in BOA were also observed.

  19. Characterization and packaging of disused sealed radioactive sources

    International Nuclear Information System (INIS)

    In Bolivia are generated disused sealed sources and radioactive waste resulting from the use of radioactive materials in industrial, research and medicine. The last includes the diagnosis and treatment. Whereas exposure to ionizing radiation is a potential hazard to personnel who applies it, to those who benefit from its use or for the community at large, it is necessary to control the activities in this field. The Instituto Boliviano de Ciencia y Tecnologia Nuclear - IBTEN is working on a regional project from International Atomic Energy Agency - IAEA, RLA/09/062 Project - TSA 4, Strengthening the National Infrastructure and Regulatory Framework for the Safe Management of Radioactive waste in Latin America. This Project has strengthened the regulatory framework regarding the safe management of radioactive waste. The aim of this work was focused primarily on the security aspects in the safe management of disused sealed sources. The tasks are listed below: 1. Characterization of disused sealed sources 2. Preparation for transport to temporary storage 3. Control of all disused radioactive sources. (author)

  20. Surface, interface and bulk materials characterization using Indus synchrotron sources

    International Nuclear Information System (INIS)

    Synchrotron radiation sources, providing intense, polarized and stable beams of ultra violet, soft and hard x-ray photons, are having great impact on physics, chemistry, biology, materials science and other areas research. In particular synchrotron radiation has revolutionized materials characterization techniques by enhancing its capabilities for investigating the structural, electronic and magnetic properties of solids. The availability of synchrotron sources and necessary instrumentation has led to considerable improvements in spectral resolution and intensities. As a result, application scope of different materials characterization techniques has tremendously increased particularly in the analysis of solid surfaces, interfaces and bulk materials. The Indian synchrotron storage ring, Indus-1 and Indus-2 are in operation at RRCAT, Indore. The UGC-DAE CSR with the help of university scientist had designed and developed an angle integrated photoelectron spectroscopy (AlPES) beam line on Indus-1 storage ring of 450 MeV and polarized light beam line for soft x-ray absorption spectroscopy (SXAS) on Indus-2 storage ring of 2.5 GeV. (author)

  1. The source term experiments project deposition sample characterization: Interim report

    International Nuclear Information System (INIS)

    A series of four experiments aimed at characterizing the radiological source term associated with postulated severe light water reactor accidents has been conducted at Argonne National Laboratory's TREAT Facility. The experiments were designed to provide dta regarding the physicochemical properties, near the point of origin, of the biologically important volatile fission products released early in such accidents. The experimental vehicles were equipped to capture representative fission products released from fuel rods undergoing severe cladding degradation in a steam environment. Test conditions of pressure, fuel heatup rate, and steam flow were selected to simulate conditions predicted for hypothetical reactor accident sequences. One of the main components of the experimental vehicle's aerosol characterization system, common to all four tests, was a sample tree. It served to suspend coupons composed of a variety of materials, some typical of reactor structures, into the fission-product-laden steam flow. These coupons collected particulates and condensing vapors. Coupons frome ach of the four tests have been examined using scanning electron microscopy and associated energy dispersive x-ray analysis. The results of these initial sample examinations are presented. They are preceeded by a brief description of the test series and the experimental vehicle. Also included is a discussion of planned posttest examinations of other aerosol characterization system components and the test fuel as well as further examinations of the sample tree coupons. Results of the additional examinations thermal-hydraulic data, and interpretation of the information for each test will be included in future reports

  2. Development and characterization of electron sources for diffraction applications

    International Nuclear Information System (INIS)

    The dream to control chemical reactions that are essential to life is now closer than ever to gratify. Recent scientific progress has made it possible to investigate phenomena and processes which deploy at the angstroms scale and at rates on the order femtoseconds. Techniques such as Ultrafast Electron Diffraction (UED) are currently able to reveal the spatial atomic configuration of systems with unit cell sizes on the order of a few nanometers with about 100 femtosecond temporal resolution. Still, major advances are needed for structural interrogation of biological systems like protein crystals, which have unit cell sizes of 10 nanometers or larger, and sample sizes of less than one micrometer. For such samples, the performance of these electron-based techniques is now limited by the quality, in particular the brightness, of the electron source. The current Ph.D. work represents a contribution towards the development and the characterization of electron sources which are essential to static and time-resolved electron diffraction techniques. The focus was on electron source fabrication and electron beam characterization measurements, using the solenoid and the aperture scan techniques, but also on the development and maintenance of the relevant experimental setups. As a result, new experimental facilities are now available in the group and, at the same time, novel concepts for generating electron beams for electron diffraction applications have been developed. In terms of existing electron sources, the capability to trigger and detect field emission from single double-gated field emitter Mo tips was successfully proven. These sharp emitter tips promise high brightness electron beams, but for investigating individual such structures, new engineering was needed. Secondly, the influence of the surface electric field on electron beam properties has been systematically performed for flat Mo photocathodes. This study is very valuable especially for state

  3. Development and characterization of electron sources for diffraction applications

    Energy Technology Data Exchange (ETDEWEB)

    Casandruc, Albert

    2015-12-15

    The dream to control chemical reactions that are essential to life is now closer than ever to gratify. Recent scientific progress has made it possible to investigate phenomena and processes which deploy at the angstroms scale and at rates on the order femtoseconds. Techniques such as Ultrafast Electron Diffraction (UED) are currently able to reveal the spatial atomic configuration of systems with unit cell sizes on the order of a few nanometers with about 100 femtosecond temporal resolution. Still, major advances are needed for structural interrogation of biological systems like protein crystals, which have unit cell sizes of 10 nanometers or larger, and sample sizes of less than one micrometer. For such samples, the performance of these electron-based techniques is now limited by the quality, in particular the brightness, of the electron source. The current Ph.D. work represents a contribution towards the development and the characterization of electron sources which are essential to static and time-resolved electron diffraction techniques. The focus was on electron source fabrication and electron beam characterization measurements, using the solenoid and the aperture scan techniques, but also on the development and maintenance of the relevant experimental setups. As a result, new experimental facilities are now available in the group and, at the same time, novel concepts for generating electron beams for electron diffraction applications have been developed. In terms of existing electron sources, the capability to trigger and detect field emission from single double-gated field emitter Mo tips was successfully proven. These sharp emitter tips promise high brightness electron beams, but for investigating individual such structures, new engineering was needed. Secondly, the influence of the surface electric field on electron beam properties has been systematically performed for flat Mo photocathodes. This study is very valuable especially for state

  4. Characterization of selenium in ambient aerosols and primary emission sources.

    Science.gov (United States)

    De Santiago, Arlette; Longo, Amelia F; Ingall, Ellery D; Diaz, Julia M; King, Laura E; Lai, Barry; Weber, Rodney J; Russell, Armistead G; Oakes, Michelle

    2014-08-19

    Atmospheric selenium (Se) in aerosols was investigated using X-ray absorption near-edge structure (XANES) spectroscopy and X-ray fluorescence (XRF) microscopy. These techniques were used to determine the oxidation state and elemental associations of Se in common primary emission sources and ambient aerosols collected from the greater Atlanta area. In the majority of ambient aerosol and primary emission source samples, the spectroscopic patterns as well as the absence of elemental correlations suggest Se is in an elemental, organic, or oxide form. XRF microscopy revealed numerous Se-rich particles, or hotspots, accounting on average for ∼16% of the total Se in ambient aerosols. Hotspots contained primarily Se(0)/Se(-II). However, larger, bulk spectroscopic characterizations revealed Se(IV) as the dominant oxidation state in ambient aerosol, followed by Se(0)/Se(-II) and Se(VI). Se(IV) was the only observed oxidation state in gasoline, diesel, and coal fly ash, while biomass burning contained a combination of Se(0)/Se(-II) and Se(IV). Although the majority of Se in aerosols was in the most toxic form, the Se concentration is well below the California Environmental Protection Agency chronic exposure limit (∼20000 ng/m(3)). PMID:25075640

  5. Developing a beta source based setup for pixel sensor characterization

    CERN Document Server

    Schouwenberg, Jeroen

    2014-01-01

    The main goal of this project is to provide mono-energetic minimum ionizing electrons from a $^{90}$Sr source using a magnetic monochromator, and thus provide a useful tool for in-lab sensor characterization. The monochromator is calibrated using a setup, with a heavy inorganic scintillator and a PMT, which has been calibrated with a $^{22}$Na gamma source. The average energy of the electrons as a function of the current in the monochromator coil is found to be $1.38\\pm0.01$ keV/mA, taking into consideration the effect of the magnetic field on the signal of the PMT. For integration into the pixel sensor test bench, scintillator-counters (a plastic scintillator connected to a PMT) are used. Their response to the electron energies is observed to follow a saturation curve, which leads to a more identical response for high energetic electrons. A preliminary pixel sensor test bench has been set up and properties such as voltage and discriminator settings have been studied as well as count rates for coincidence cou...

  6. Characterization of urban aerosol sources in Debrecen, Hungary

    International Nuclear Information System (INIS)

    Complete text of publication follows. Aerosol pollution represents significant health hazard in urban environments. Despite the fact that Debrecen has not a much stressed environment the city is highly exposed to aerosol pollution. In order to evaluate the impact of aerosol particles on health, the knowledge of the particle size distribution, chemical composition, sources, and their change in time and space is needed. This work presents a source apportionment study of fine (particles with aerodynamic diameter less than 2.5 μm) and coarse (particles with aerodynamic diameter between 2.5 and 10 μm) particulate matter in Debrecen by following the evolution of the elemental components with hourly time resolution. The variation of the elemental concentrations, their periodicity, correlation with other elements and meteorological parameters were studied on samples collected in different seasons. Aerosol sources were determined using the positive matrix factorization (PMF) method. Aerosol samples were collected in the garden of the ATOMKI with a 2-stage sequential streaker sampler manufactured by PIXE International, which collected the fine and coarse fraction separately with few hours' time resolution. Between October 2007 and January 2009 five 10-days long sampling campaigns were carried out. The elemental composition was determined by Particle Induced X-ray emission (PIXE) for Z ≥ 13, and the elemental carbon (BC) content was estimated with a smoke stain reflectometer. Source apportionment was carried out with the PMF receptor model developed for aerosol source characterization, provided by US EPA. Mass of species apportioned to factor, percentage of species apportioned to factors and average factor contributions of the campaigns, of working days and weekends and within the days were calculated. The PMF analysis resulted seven factors in the fine and seven factors in the coarse mode. The main sources of atmospheric aerosol in the city of Debrecen were traffic

  7. Dosimetric characterization of two radium sources for retrospective dosimetry studies

    Energy Technology Data Exchange (ETDEWEB)

    Candela-Juan, C., E-mail: ccanjuan@gmail.com [Radiation Oncology Department, La Fe University and Polytechnic Hospital, Valencia 46026, Spain and Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain); Karlsson, M. [Division of Radiological Sciences, Department of Medical and Health Sciences, Linköping University, Linköping SE 581 85 (Sweden); Lundell, M. [Department of Medical Physics and Oncology, Karolinska University Hospital and Karolinska Institute, Stockholm SE 171 76 (Sweden); Ballester, F. [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain); Tedgren, Å. Carlsson [Division of Radiological Sciences, Department of Medical and Health Sciences, Linköping University, Linköping SE 581 85, Sweden and Swedish Radiation Safety Authority, Stockholm SE 171 16 (Sweden)

    2015-05-15

    Purpose: During the first part of the 20th century, {sup 226}Ra was the most used radionuclide for brachytherapy. Retrospective accurate dosimetry, coupled with patient follow up, is important for advancing knowledge on long-term radiation effects. The purpose of this work was to dosimetrically characterize two {sup 226}Ra sources, commonly used in Sweden during the first half of the 20th century, for retrospective dose–effect studies. Methods: An 8 mg {sup 226}Ra tube and a 10 mg {sup 226}Ra needle, used at Radiumhemmet (Karolinska University Hospital, Stockholm, Sweden), from 1925 to the 1960s, were modeled in two independent Monte Carlo (MC) radiation transport codes: GEANT4 and MCNP5. Absorbed dose and collision kerma around the two sources were obtained, from which the TG-43 parameters were derived for the secular equilibrium state. Furthermore, results from this dosimetric formalism were compared with results from a MC simulation with a superficial mould constituted by five needles inside a glass casing, placed over a water phantom, trying to mimic a typical clinical setup. Calculated absorbed doses using the TG-43 formalism were also compared with previously reported measurements and calculations based on the Sievert integral. Finally, the dose rate at large distances from a {sup 226}Ra point-like-source placed in the center of 1 m radius water sphere was calculated with GEANT4. Results: TG-43 parameters [including g{sub L}(r), F(r, θ), Λ, and s{sub K}] have been uploaded in spreadsheets as additional material, and the fitting parameters of a mathematical curve that provides the dose rate between 10 and 60 cm from the source have been provided. Results from TG-43 formalism are consistent within the treatment volume with those of a MC simulation of a typical clinical scenario. Comparisons with reported measurements made with thermoluminescent dosimeters show differences up to 13% along the transverse axis of the radium needle. It has been estimated that

  8. Performing monkeys of Bangladesh: characterizing their source and genetic variation.

    Science.gov (United States)

    Hasan, M Kamrul; Feeroz, M Mostafa; Jones-Engel, Lisa; Engel, Gregory A; Akhtar, Sharmin; Kanthaswamy, Sree; Smith, David Glenn

    2016-04-01

    The acquisition and training of monkeys to perform is a centuries-old tradition in South Asia, resulting in a large number of rhesus macaques kept in captivity for this purpose. The performing monkeys are reportedly collected from free-ranging populations, and may escape from their owners or may be released into other populations. In order to determine whether this tradition involving the acquisition and movement of animals has influenced the population structure of free-ranging rhesus macaques in Bangladesh, we first characterized the source of these monkeys. Biological samples from 65 performing macaques collected between January 2010 and August 2013 were analyzed for genetic variation using 716 base pairs of mitochondrial DNA. Performing monkey sequences were compared with those of free-ranging rhesus macaque populations in Bangladesh, India and Myanmar. Forty-five haplotypes with 116 (16 %) polymorphic nucleotide sites were detected among the performing monkeys. As for the free-ranging rhesus population, most of the substitutions (89 %) were transitions, and no indels (insertion/deletion) were observed. The estimate of the mean number of pair-wise differences for the performing monkey population was 10.1264 ± 4.686, compared to 14.076 ± 6.363 for the free-ranging population. Fifteen free-ranging rhesus macaque populations were identified as the source of performing monkeys in Bangladesh; several of these populations were from areas where active provisioning has resulted in a large number of macaques. The collection of performing monkeys from India was also evident. PMID:26758818

  9. Comprehensive airborne characterization of aerosol from a major bovine source

    Directory of Open Access Journals (Sweden)

    H. Jonsson

    2008-09-01

    Full Text Available We report an extensive airborne characterization of aerosol downwind of a massive bovine source in the San Joaquin Valley (California on two flights during July 2007. The Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS Twin Otter probed chemical composition, particle size distribution, mixing state, sub- and supersaturated water uptake behavior, light scattering properties, and the interrelationship between these parameters and meteorology. Total PM1.0 levels and concentrations of organics, nitrate, and ammonium were enhanced in the plume from the source as compared to the background aerosol. Organics dominated the plume aerosol mass (~56–64%, followed either by sulfate or nitrate, and then ammonium. Particulate amines were detected in the plume aerosol by a particle-into-liquid sampler (PILS and via mass spectral markers in the Aerodyne C-ToF-AMS. Amines were found to be a significant atmospheric base even in the presence of ammonia; particulate amine concentrations are estimated as at least 14–23% of that of ammonium in the plume. Enhanced sub- and supersaturated water uptake and reduced refractive indices were coincident with lower organic mass fractions, higher nitrate mass fractions, and the detection of amines. The likelihood of suppressed droplet growth owing to kinetic limitations from hydrophobic organic material is explored. After removing effects associated with size distribution and mixing state, the normalized activated fraction of cloud condensation nuclei (CCN increased as a function of the subsaturated hygroscopic growth factor, with the highest activated fractions being consistent with relatively lower organic mass fractions and higher nitrate mass fractions. Subsaturated hygroscopic growth factors for the organic fraction of the aerosol are estimated based on employing the Zdanovskii-Stokes Robinson (ZSR mixing rule. Representative values for a parameterization treating particle water

  10. Comprehensive airborne characterization of aerosol from a major bovine source

    Directory of Open Access Journals (Sweden)

    A. Sorooshian

    2008-06-01

    Full Text Available We report an extensive airborne characterization of aerosol downwind of a massive bovine source in the San Joaquin Valley (California on two flights during July 2007. The Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS Twin Otter probed chemical composition, particle size distribution, mixing state, sub- and supersaturated water uptake behavior, light scattering properties, and the interrelationship between these parameters and meteorology. Total PM1.0 levels and concentrations of organics, nitrate, and ammonium were enhanced in the plume from the source as compared to the background aerosol. Organics dominated the plume aerosol mass (~56–64%, followed either by sulfate or nitrate, and then ammonium. Particulate amines were detected in the plume aerosol by a particle-into-liquid sampler (PILS and via mass spectral markers in the Aerodyne cToF-AMS. Amines were found to be a significant atmospheric base even in the presence of ammonia; particulate amine concentrations are estimated as at least 14–23% of that of ammonium in the plume. Enhanced sub- and supersaturated water uptake and reduced refractive indices were coincident with lower organic mass fractions, higher nitrate mass fractions, and the detection of amines. Kinetic limitations due to hydrophobic organic material are shown to have likely suppressed droplet growth. After removing effects associated with size distribution and mixing state, the normalized activated fraction of cloud condensation nuclei (CCN increased as a function of the subsaturated hygroscopic growth factor, with the highest activated fractions being consistent with relatively lower organic mass fractions and higher nitrate mass fractions. Subsaturated hygroscopic growth factors for the organic fraction of the aerosol are estimated based on employing the Zdanovskii-Stokes Robinson (ZSR mixing rule. Representative values for a parameterization treating particle water uptake in both the

  11. A method for characterizing the stability of light sources.

    Science.gov (United States)

    Sanvito, Tiziano; Zocca, Francesca; Pullia, Alberto; Potenza, Marco

    2013-10-21

    We describe a method for measuring small fluctuations in the intensity of a laser source with a resolution of 10⁻⁴. The current signal generated by a PIN diode is passed to a front-end electronics that discriminates the AC from the DC components, which are physically separated and propagated along circuit paths with different gains. The gain long the AC signal path is set one order of magnitude larger than that along the DC signal path in such a way to optimize the measurement dynamic range. We then derive the relative fluctuation signal by normalizing the input-referred AC signal component to its input-referred DC counterpart. In this way the fluctuation of the optical signal waveform relative to the mean power of the laser is obtained. A "Noise-Scattering-Pattern method" and a "Signal-Power-Spectrum method" are then used to analyze the intensity fluctuations from three different solid-state lasers. This is a powerful tool for the characterization of the intensity stability of lasers. Applications are discussed. PMID:24150307

  12. Characterization of French Coriander Oil as Source of Petroselinic Acid

    Directory of Open Access Journals (Sweden)

    Evelien Uitterhaegen

    2016-09-01

    Full Text Available Coriander vegetable oil was extracted from fruits of French origin in a 23% yield. The oil was of good quality, with a low amount of free fatty acids (1.8% and a concurrently high amount of triacylglycerols (98%. It is a rich source of petroselinic acid (C18:1n-12, an important renewable building block, making up 73% of all fatty acids, with also significant amounts of linoleic acid (14%, oleic acid (6%, and palmitic acid (3%. The oil was characterized by a high unsaponifiable fraction, comprising a substantial amount of phytosterols (6.70 g/kg. The main sterol markers were β-sitosterol (35% of total sterols, stigmasterol (24%, and Δ7-stigmastenol (18%. Squalene was detected at an amount of 0.2 g/kg. A considerable amount of tocols were identified (500 mg/kg and consisted mainly of tocotrienols, with γ-tocotrienol as the major compound. The phospholipid content was low at 0.3%, of which the main phospholipid classes were phosphatidic acid (33%, phosphatidylcholine (25%, phosphatidylinositol (17%, and phosphatidylethanolamine (17%. About 50% of all phospholipids were non-hydratable. The β-carotene content was low at 10 mg/kg, while a significant amount of chlorophyll was detected at about 11 mg/kg. An iron content of 1.4 mg/kg was determined through element analysis of the vegetable oil. The influence of fruit origin on the vegetable oil composition was shown to be very important, particularly in terms of the phospholipids, sterols, and tocols composition.

  13. Characterization of French Coriander Oil as Source of Petroselinic Acid.

    Science.gov (United States)

    Uitterhaegen, Evelien; Sampaio, Klicia A; Delbeke, Elisabeth I P; De Greyt, Wim; Cerny, Muriel; Evon, Philippe; Merah, Othmane; Talou, Thierry; Stevens, Christian V

    2016-01-01

    Coriander vegetable oil was extracted from fruits of French origin in a 23% yield. The oil was of good quality, with a low amount of free fatty acids (1.8%) and a concurrently high amount of triacylglycerols (98%). It is a rich source of petroselinic acid (C18:1n-12), an important renewable building block, making up 73% of all fatty acids, with also significant amounts of linoleic acid (14%), oleic acid (6%), and palmitic acid (3%). The oil was characterized by a high unsaponifiable fraction, comprising a substantial amount of phytosterols (6.70 g/kg). The main sterol markers were β-sitosterol (35% of total sterols), stigmasterol (24%), and Δ⁷-stigmastenol (18%). Squalene was detected at an amount of 0.2 g/kg. A considerable amount of tocols were identified (500 mg/kg) and consisted mainly of tocotrienols, with γ-tocotrienol as the major compound. The phospholipid content was low at 0.3%, of which the main phospholipid classes were phosphatidic acid (33%), phosphatidylcholine (25%), phosphatidylinositol (17%), and phosphatidylethanolamine (17%). About 50% of all phospholipids were non-hydratable. The β-carotene content was low at 10 mg/kg, while a significant amount of chlorophyll was detected at about 11 mg/kg. An iron content of 1.4 mg/kg was determined through element analysis of the vegetable oil. The influence of fruit origin on the vegetable oil composition was shown to be very important, particularly in terms of the phospholipids, sterols, and tocols composition. PMID:27617992

  14. An Open-Source Approach for Catchment's Physiographic Characterization

    Science.gov (United States)

    Di Leo, M.; Di Stefano, M.

    2013-12-01

    A water catchment's hydrologic response is intimately linked to its morphological shape, which is a signature on the landscape of the particular climate conditions that generated the hydrographic basin over time. Furthermore, geomorphologic structures influence hydrologic regimes and land cover (vegetation). For these reasons, a basin's characterization is a fundamental element in hydrological studies. Physiographic descriptors have been extracted manually for long time, but currently Geographic Information System (GIS) tools ease such task by offering a powerful instrument for hydrologists to save time and improve accuracy of result. Here we present a program combining the flexibility of the Python programming language with the reliability of GRASS GIS, which automatically performing the catchment's physiographic characterization. GRASS (Geographic Resource Analysis Support System) is a Free and Open Source GIS, that today can look back on 30 years of successful development in geospatial data management and analysis, image processing, graphics and maps production, spatial modeling and visualization. The recent development of new hydrologic tools, coupled with the tremendous boost in the existing flow routing algorithms, reduced the computational time and made GRASS a complete toolset for hydrological analysis even for large datasets. The tool presented here is a module called r.basin, based on GRASS' traditional nomenclature, where the "r" stands for "raster", and it is available for GRASS version 6.x and more recently for GRASS 7. As input it uses a Digital Elevation Model and the coordinates of the outlet, and, powered by the recently developed r.stream.* hydrological tools, it performs the flow calculation, delimits the basin's boundaries and extracts the drainage network, returning the flow direction and accumulation, the distance to outlet and the hill slopes length maps. Based on those maps, it calculates hydrologically meaningful shape factors and

  15. Underground structure characterization using motor vehicles as passive seismic sources

    Science.gov (United States)

    Kuzma, H. A.; Liu, Y.; Zhao, Y.; Rector, J.; Vaidya, S.

    2009-12-01

    The ability to detect and characterize underground voids will be critical to the success of On-Site Inspections (OSI) as mandated by the nuclear Comprehensive Test Ban Treaty (CTBT). OSIs may be conducted in order to successfully locate the Ground Zero of underground tests as well as infrastructure related to testing. Recently, our team has shown the potential of a new technique to detect underground objects using the amplitude of seismic surface waves generated by motor vehicles. In an experiment conducted in June, 2009 we were able to detect an abandoned railroad tunnel by recognizing a clear pattern in the surface waves scattered by the tunnel, using a signal generated by driving a car on a dirt road across the tunnel. Synthetic experiments conducted using physically realistic wave-equation models further suggest that the technique can be readily applied to detecting underground features: it may be possible to image structures of importance to OSI simply by laying out an array of geophones (or using an array already in place for passive listening for event aftershocks) and driving vehicles around the site. We present evidence from a set of field experiments and from synthetic modeling and inversion studies to illustrate adaptations of the technique for OSI. Signature of an abandoned underground railroad tunnel at Donner Summit, CA. To produce this image, a line of geophones was placed along a dirt road perpendicular to the tunnel (black box) and a single car was driven along the road. A normalized mean power-spectrum is displayed on a log scale as a function of meters from the center of the tunnel. The top of the tunnel was 18m below ground surface. The tunnel anomaly is made up of a shadow (light) directly above the tunnel and amplitude build-up (dark) on either side of the tunnel. The size of the anomaly (6 orders of magnitude) suggests that the method can be extended to find deep structures at greater distances from the source and receivers.

  16. Geoacoustic characterization by the image source method: a sensitivity study

    OpenAIRE

    PINSON, Samuel; Guillon, Laurent; Cervenka, Pierre

    2012-01-01

    International audience; A new method for measuring the sound speed profile of the seafloor has been recently proposed (JASA, vol. 128, pp. 1685-1693): the image source method. This method is based on a physical model of the acoustic field generated by a point source and reflected by a layered media. Under the Born approximation, the reflected signal can be modeled as a sum of contributions coming from image sources relative to the seabed layers. Consequently, the seabed geometry and sound spe...

  17. Photon statistics characterization of a single photon source

    OpenAIRE

    Alleaume, Romain; Treussart, Francois; Courty, Jean-Michel; Roch, Jean-Francois

    2003-01-01

    n a recent experiment, we reported the time-domain intensity noise measurement of a single photon source relying on single molecule fluorescence control. In this article we present data processing, starting from photocount timestamps. The theoretical analytical expression of the time-dependent Mandel parameter Q(T) of an intermittent single photon source is derived from ONOFF dynamics . Finally, source intensity noise analysis using the Mandel parameter is quantitatively compared to the usual...

  18. Development of methodology for the characterization of radioactive sealed sources

    International Nuclear Information System (INIS)

    Sealed radioactive sources are widely used in many applications of nuclear technology in industry, medicine, research and others. The International Atomic Energy Agency (IAEA) estimates tens of millions sources in the world. In Brazil, the number is about 500 thousand sources, if the Americium-241 sources present in radioactive lightning rods and smoke detectors are included in the inventory. At the end of the useful life, most sources become disused, constitute a radioactive waste, and are then termed spent sealed radioactive sources (SSRS). In Brazil, this waste is collected by the research institutes of the Nuclear Commission of Nuclear Energy and kept under centralized storage, awaiting definition of the final disposal route. The Waste Management Laboratory (WML) at the Nuclear and Energy Research Institute is the main storage center, having received until July 2010 about 14.000 disused sources, not including the tens of thousands of lightning rod and smoke detector sources. A program is underway in the WML to replacing the original shielding by a standard disposal package and to determining the radioisotope content and activity of each one. The identification of the radionuclides and the measurement of activities will be carried out with a well type ionization chamber. This work aims to develop a methodology for measuring or to determine the activity SSRS stored in the WML accordance with its geometry and determine their uncertainties. (author)

  19. Secondary metabolites from natural sources: chemical and pharmacological characterization

    OpenAIRE

    Festa, Carmen

    2010-01-01

    Natural products have long been a source of bioactive metabolites utilized for the treatment of human disease. In spite the impressive progress of new competing methodologies, as for example, combinatorial chemistry and high-throughput screening or genetic engineering, natural products remain a valuable source of bioactive compounds with therapeutic potential. In recent years, the marine environment has been seen as a vast resource for the discovery of structurally unique bioactive secon...

  20. Pseudo-forces methodology to be used in characterization of structure-borne sound sources

    NARCIS (Netherlands)

    Janssens, M.H.A.; Verheij, J.W.

    2000-01-01

    In the analysis of machinery noise generation and transmission the aspect of sound source characterization is of importance. Unlike for airborne sources, no widely applicable and practical methods are available yet for structure-borne sound sources. This paper presents the `pseudo-forces' methodolog

  1. Characterization of PM10 sources in the central Mediterranean

    Science.gov (United States)

    Calzolai, G.; Nava, S.; Lucarelli, F.; Chiari, M.; Giannoni, M.; Becagli, S.; Traversi, R.; Marconi, M.; Frosini, D.; Severi, M.; Udisti, R.; di Sarra, A.; Pace, G.; Meloni, D.; Bommarito, C.; Monteleone, F.; Anello, F.; Sferlazzo, D. M.

    2015-12-01

    The Mediterranean Basin atmosphere is influenced by both strong natural and anthropogenic aerosol emissions and is also subject to important climatic forcings. Several programs have addressed the study of the Mediterranean basin; nevertheless important pieces of information are still missing. In this framework, PM10 samples were collected on a daily basis on the island of Lampedusa (35.5° N, 12.6° E; 45 m a.s.l.), which is far from continental pollution sources (the nearest coast, in Tunisia, is more than 100 km away). After mass gravimetric measurements, different portions of the samples were analyzed to determine the ionic content by ion chromatography (IC), the soluble metals by inductively coupled plasma atomic emission spectrometry (ICP-AES), and the total (soluble + insoluble) elemental composition by particle-induced x-ray emission (PIXE). Data from 2007 and 2008 are used in this study. The Positive Matrix Factorization (PMF) model was applied to the 2-year long data set of PM10 mass concentration and chemical composition to assess the aerosol sources affecting the central Mediterranean basin. Seven sources were resolved: sea salt, mineral dust, biogenic emissions, primary particulate ship emissions, secondary sulfate, secondary nitrate, and combustion emissions. Source contributions to the total PM10 mass were estimated to be about 40 % for sea salt, around 25 % for mineral dust, 10 % each for secondary nitrate and secondary sulfate, and 5 % each for primary particulate ship emissions, biogenic emissions, and combustion emissions. Large variations in absolute and relative contributions are found and appear to depend on the season and on transport episodes. In addition, the secondary sulfate due to ship emissions was estimated and found to contribute by about one-third to the total sulfate mass. Results for the sea-salt and mineral dust sources were compared with estimates of the same contributions obtained from independent approaches, leading to an

  2. Characterization of a Common-Source Amplifier Using Ferroelectric Transistors

    Science.gov (United States)

    Hunt, Mitchell; Sayyah, Rana; MacLeond, Todd C.; Ho, Pat D.

    2010-01-01

    This paper presents empirical data that was collected through experiments using a FeFET in the established common-source amplifier circuit. The unique behavior of the FeFET lends itself to interesting and useful operation in this widely used common-source amplifier. The paper examines the effect of using a ferroelectric transistor for the amplifier. It also examines the effects of varying load resistance, biasing, and input voltages on the output signal and gives several examples of the output of the amplifier for a given input. The difference between a commonsource amplifier using a ferroelectric transistor and that using a MOSFET is addressed.

  3. Genetic characterization of Arcobacter isolates from various sources.

    Science.gov (United States)

    Shah, A H; Saleha, A A; Zunita, Z; Cheah, Y K; Murugaiyah, M; Korejo, N A

    2012-12-01

    Arcobacter is getting more attention due to its detection from wide host-range and foods of animal origin. The objective of this study was to determine the prevalence of Arcobacter spp. in various sources at farm level and beef retailed in markets in Malaysia and to assess the genetic relatedness among them. A total of 273 samples from dairy cattle including cattle (n=120), floor (n=30), water (n=18) and milk (n=105) as well as 148 beef samples collected from retail markets were studied. The overall prevalence of Arcobacter in various sources was 15% (63/421). However, source-wise detection rate of Arcobacter spp. was recorded as 26.66% (8/30) in floor, 26.3% (39/148) in beef, 11.11% (2/18) in water, 7.6% (8/105) in milk and 6.66% (8/120) in cattle. Arcobacter butzleri was the frequently isolated species however, a total of 75%, 66.7%, 53.8%, 50% and 12.5%% samples from floor, milk, beef, water and cattle, respectively, were carrying more than one species simultaneously. One (12.5%) cattle and beef sample (2.5%) found to be carrying one Arcobacter spp., A. skirrowii, only. Typing of Arcobacter isolates was done though pulsed field gel electrophoresis (PFGE) after digested with Eag1 restriction endonuclease (RE). Digestion of genomic DNA of Arcobacter from various sources yielded 12 major clusters (≥ 50% similarity) which included 29 different band patterns. A number of closely related A. butzleri isolates were found from beef samples which indicate cross contamination of common type of Arcobacter. Fecal shedding of Arcobacter by healthy animals can contaminate water and milk which may act as source of infection in humans. PMID:22739058

  4. Characterization of PM10 sources in the central Mediterranean

    Directory of Open Access Journals (Sweden)

    G. Calzolai

    2015-07-01

    Full Text Available The Mediterranean Basin atmosphere is influenced by both strong natural and anthropogenic aerosol emissions, and is also subject to important climatic forcings. Several programs have addressed the study of the Mediterranean basin; nevertheless important pieces of information are still missing. In this framework, PM10 samples were collected on a daily basis on the island of Lampedusa (35.5° N, 12.6° E, 45 m a.s.l., which is far from continental pollution sources (the nearest coast, in Tunisia, is more than 100 km away. After mass gravimetric measurements, different portions of the samples were analyzed to determine the ionic content by Ion Chromatography (IC, the soluble metals by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES, and the total (soluble + insoluble elemental composition by Particle Induced X-ray Emission (PIXE. Data from years 2007 and 2008 are used in this study. The Positive Matrix Factorization (PMF model was applied to the 2 year long data set of PM10 mass concentration and chemical composition to assess the aerosol sources affecting the Central Mediterranean basin. Seven sources were resolved: sea-salt, mineral dust, biogenic emissions, primary particulate ship emissions, secondary sulphate, secondary nitrate, and combustion emissions. Source contributions to the total PM10 mass were estimated to be about 40 % for sea-salt, around 25 % for mineral dust, 10 % each for secondary nitrate and secondary sulphate, and 5 % each for primary particulate ship emissions, biogenic emissions, and combustion emissions. Large variations in absolute and relative contributions are found and appear to depend on the season and on transport episodes. In addition, the secondary sulphate due to ship emissions was estimated, and found to contribute by about one third to the total sulphate mass. Results for the sea-salt and mineral dust sources were compared with estimates of the same contributions obtained from independent

  5. Characterization of nuclear sources via two-neutron intensity interferometry

    Energy Technology Data Exchange (ETDEWEB)

    Ghetti, R.; Colonna, N.; Helgesson, J.; De Filippo, E.; Tagliente, G.; Anzalone, A.; Bellini, V.; Carlen, L.; Cavallaro, S.; Celano, L.; D' Erasmo, G.; Di Santo, D.; Fiore, E.M.; Fokin, A.; Geraci, M.; Jakobsson, B.; Kuznetsov, A.; Lanzano, G.; Mahboub, D.; Murin, Yu.; Maartensson, J.; Pagano, A.; Palazzolo, F.; Palomba, M.; Pantaleo, A.; Paticchio, V.; Potenza, R.; Riera, G.; Siwek, A.; Sperduto, M.L.; Sutera, C.; Urrata, M.; Westerberg, L

    1999-11-15

    The neutron energy spectrum and the two-neutron correlation function have been measured for the E/A=45 MeV Ni + Al reaction in order to assess the space-time characteristics of the neutron emitting source. When comparing the data to a statistical model, the kinetic energy spectra, the integrated correlation function as well as the longitudinal correlation function are reproduced by one single source. However, only the inclusion of a short-lived pre-equilibrium component can account for the stronger correlation exhibited by neutron pairs emitted with high total momentum. The correlation function from events defined as peripheral by constraints on the highest charge of the projectile-like fragment does show a significantly weaker correlation than the minimum bias sample.

  6. An implanted $^{228}$Ra source for response characterization of bolometers

    CERN Multimedia

    TeO$_{2}$ crystals are used as bolometers in experiments searching for $\\beta-\\beta$- decay without emission of neutrinos. One of the most important issues in this extremely delicate kind of experiments is the discrimination of the background from the real signal. A deep knowledge of the bolometric response to $\\alpha$-particles is therefore needed to recognize and discard them, since it has been proven that $\\alpha$-contamination could be a major contribution in our background budget. We would like to use ISOLDE’s capability of implanting $^{228}$Ra to make a long-lived source feeding several monochromatic $\\alpha$- and recoiling nuclei, with little or no $\\alpha$-peak broadening due to the source itself, for tests of our detectors in Milano and Gran Sasso INFN National Lab

  7. CHARACTERIZATION OF URBAN AEROSOL SOURCES IN DEBRECEN, HUNGARY

    Directory of Open Access Journals (Sweden)

    ZSÓFIA KERTÉSZ

    2008-12-01

    Full Text Available Debrecen is an average middle European city from the point of view of aerosol pollution. Its location makes the city an ideal place for observing aerosol transport processes. Systematic investigation ofatmospheric aerosol of the east-Hungarian region has been performed in the Institute of Nuclear Research of the Hungarian Academy of Sciences for 20 years by accelerator based elemental analytical technique. As a complementation of this research we observed the size distribution andshort-term time variation of the elemental component of fine (PM2.5 and coarse (PM10-PM2.5 urban aerosol in the frame of sampling campaigns during 2007 and 2008 in a downtown site of Debrecen.Meteorological parameters were also recorded parallel to the aerosol sampling. Elemental concentrations (Z ≥ 12 were determined by particle induced X-ray emission (PIXE analytical technique at the Laboratory of Ion Beam Applications (IBA of the ATOMKI. On the obtained database six sources of the urban aerosol were identified: 2 types of soil, domestic heating, sulphate originating from long range transport processes, an unidentified source enriched with chlorine andtraffic. Emission episodes were also observed. The short-time variation of urban aerosol combined with meteorological data and with mass size distribution serves as a basis to reach a better understanding of the aerosol sources in receptor areas, to select local emission and long range transport episodes, to follow the evolution of aerosol, and to make a better estimate on the health impact.

  8. Pathogens in Dairy Farming: Source Characterization and Groundwater Impacts

    Science.gov (United States)

    Atwill, E. R.; Watanabe, N.; Li, X.; Hou, L.; Harter, T.; Bergamaschi, B.

    2007-12-01

    Intense animal husbandry is of growing concern as a potential contamination source of enteric pathogens as well as antibiotics. To assess the public health risk from pathogens and their hydrologic pathways, we hypothesize that the animal farm is not a homogeneous diffuse source, but that pathogen loading to the soil and, therefore, to groundwater varies significantly between the various management units of a farm. A dairy farm, for example, may include an area with calf hutches, corrals for heifers of various ages, freestalls and exercise yards for milking cows, separate freestalls for dry cows, a hospital barn, a yard for collection of solid manure, a liquid manure storage lagoon, and fields receiving various amounts of liquid and solid manure. Pathogen shedding and, hence, therapeutic and preventive pharmaceutical treatments vary between these management units. We are implementing a field reconnaissance program to determine the occurrence of three different pathogens ( E. coli, Salmonella, Campylobacter) and one indicator organism ( Enterococcus) at the ground-surface and in shallow groundwater of seven different management units on each of two farms, and in each of four seasons (spring/dry season, summer/irrigation season, fall/dry season, winter/rainy season). Initial results indicate that significant differences exist in the occurrence of these pathogens between management units and between organisms. These differences are weakly reflected in their occurrence in groundwater, despite the similarity of the shallow geologic environment across these sites. Our results indicate the importance of differentiating sources within a dairy farm and the importance of understanding subsurface transport processes for these pathogens.

  9. Electrical Conductivity Imaging Using Controlled Source Electromagnetics for Subsurface Characterization

    Science.gov (United States)

    Miller, C. R.; Routh, P. S.; Donaldson, P. R.

    2004-05-01

    Controlled Source Audio-Frequency Magnetotellurics (CSAMT) is a frequency domain electromagnetic (EM) sounding technique. CSAMT typically uses a grounded horizontal electric dipole approximately one to two kilometers in length as a source. Measurements of electric and magnetic field components are made at stations located ideally at least four skin depths away from the transmitter to approximate plane wave characteristics of the source. Data are acquired in a broad band frequency range that is sampled logarithmically from 0.1 Hz to 10 kHz. The usefulness of CSAMT soundings is to detect and map resistivity contrasts in the top two to three km of the Earth's surface. Some practical applications that CSAMT soundings have been used for include mapping ground water resources; mineral/precious metals exploration; geothermal reservoir mapping and monitoring; petroleum exploration; and geotechnical investigations. Higher frequency data can be used to image shallow features and lower frequency data are sensitive to deeper structures. We have a 3D CSAMT data set consisting of phase and amplitude measurements of the Ex and Hy components of the electric and magnetic fields respectively. The survey area is approximately 3 X 5 km. Receiver stations are situated 50 meters apart along a total of 13 lines with 8 lines bearing approximately N60E and the remainder of the lines oriented orthogonal to these 8 lines. We use an unconstrained Gauss-Newton method with positivity to invert the data. Inversion results will consist of conductivity versus depth profiles beneath each receiver station. These 1D profiles will be combined into a 3D subsurface conductivity image. We will include our interpretation of the subsurface conductivity structure and quantify the uncertainties associated with this interpretation.

  10. Sound speed profile characterization by the image source method

    OpenAIRE

    PINSON, Samuel; Guillon, Laurent

    2010-01-01

    This paper presents the first results of an imaging technique that measures the geoacoustic structure of a seafloor in shallow water areas. The devices used were a broadband 100 Hz–6 kHz acoustic source towed by a ship and a vertical array. Among all the acoustic paths existing in the water column, two are used: the direct one and the seabed-reflected one, the latter being composed of the reflections from the seafloor’s surface as well as that from each buried layer. Due to the good time re...

  11. Characterization of an inductively coupled plasma source with convergent nozzle

    Science.gov (United States)

    Dropmann, Michael; Clements, Kathryn; Edgren, Josh; Laufer, Rene; Herdrich, Georg; Matthews, Lorin; Hyde, Truell

    2015-11-01

    The inductively heated plasma generator (IPG6-B) located in the CASPER labs at Baylor University has recently been characterized for both air, nitrogen and helium. A primary area of research within the intended scope of the instrument is the analysis of material degradation under high heat fluxes such as those imposed by a plasma during atmospheric entry of a spacecraft and at the divertor within various fusion experiment. In order to achieve higher flow velocities and respectively higher heat fluxes, a new exit flange has been designed to allow the installation of nozzles with varying geometries at the exit of the plasma generator. This paper will discuss characterization of the plasma generator for a convergent nozzle accelerating the plasma jet to supersonic velocity. The diagnostics employed include a cavity calorimeter to measure the total plasma power, a Pitot probe to measure stagnation pressure and a heat flux probe to measure the local heat flux. Radial profiles of stagnation pressure and heat flux allowing the determination of the local plasma enthalpy in the plasma jet will be presented. Support from the NSF and the DOE (award numbers PHY-1262031 and PHY-1414523) is gratefully acknowledged.

  12. Characterization and source determination of air pollution in Ankara

    International Nuclear Information System (INIS)

    The sources of air pollution in Ankara and the effect of these sources on rainwater composition were studied by collecting rainwater and aerosol samples over a one year period in 1988. The rain water was not acidic owing to high concentrations of alkaline soil particles in the atmosphere. However, the concentrations of acid forming ions, such as SO42- and NO3-, were higher than concentrations expected in a typical urban atmosphere. Most of the SO42- in rain water was in the form of CaSO4. The ions most efficiently scavenged from the atmosphere were found to be SO42- and Ca2+. Atomspheric concentrations of approximately thirty elements indicated that road dust, motor vehicles, coal and oil combustion are the main components of aerosols over the city. Elements which have origins in industrial processes were not enriched substantially and do not show seasonal dependence, whereas elements which originate from coal combustion for residential heating are highly enriched and have higher concentrations in the winter. Road dust was enriched in Pb and Br and does not show characteristic soil composition. (author). 8 refs, 5 figs, 7 tabs

  13. Wetlands Assessment for site characterization, Advanced Neutron Source (ANS)

    Energy Technology Data Exchange (ETDEWEB)

    Wade, M.C.; Socolof, M.L. [Oak Ridge National Lab., TN (United States). Energy Div.; Rosensteel, B.; Awl, D. [JAYCOR, Vienna, VA (United States)

    1994-10-01

    This Wetlands Assessment has been prepared in accordance with the Department of Energy`s (DOE) Code of Federal Regulations (CFR) 10 CFR 1022, Compliance with Floodplain/Wetlands Environmental Review Requirements, which established the policy and procedure for implementing Executive Order 11990, Protection of Wetlands. The proposed action is to conduct characterization activities in or near wetlands at the ANS site. The proposed action will covered under a Categorical Exclusion, therefore this assessment is being prepared as a separate document [10 CFR 1022.12(c)]. The purpose of this Wetlands Assessment is to fulfill the requirements of 10 CFR 1022.12(a) by describing the project, discussing the effects of the proposed action upon the wetlands, and considering alternatives to the proposed action.

  14. Wetlands Assessment for site characterization, Advanced Neutron Source (ANS)

    International Nuclear Information System (INIS)

    This Wetlands Assessment has been prepared in accordance with the Department of Energy's (DOE) Code of Federal Regulations (CFR) 10 CFR 1022, Compliance with Floodplain/Wetlands Environmental Review Requirements, which established the policy and procedure for implementing Executive Order 11990, Protection of Wetlands. The proposed action is to conduct characterization activities in or near wetlands at the ANS site. The proposed action will covered under a Categorical Exclusion, therefore this assessment is being prepared as a separate document [10 CFR 1022.12(c)]. The purpose of this Wetlands Assessment is to fulfill the requirements of 10 CFR 1022.12(a) by describing the project, discussing the effects of the proposed action upon the wetlands, and considering alternatives to the proposed action

  15. Characterization of Source and Wave Propagation Effects of Volcano-seismic Events and Tremor Using the Amplitude Source Location Method

    Science.gov (United States)

    Kumagai, H.; Londono, J. M.; López, C. M.; Ruiz, M. C.; Mothes, P. A.; Maeda, Y.

    2015-12-01

    We propose application of the amplitude source location (ASL) method to characterize source and wave propagation effects of volcano-seismic events and tremor observed at different volcanoes. We used this method to estimate the source location and source amplitude from high-frequency (5-10 Hz) seismic amplitudes under the assumption of isotropic S-wave radiation. We estimated the cumulative source amplitude (Is) as the offset value of the time-integrated envelope of the vertical seismogram corrected for geometrical spreading and medium attenuation in the 5-10 Hz band. We studied these parameters of tremor signals associated with eruptions and explosion events at Tungurahua volcano, Ecuador; long-period (LP) events at Cotopaxi volcano, Ecuador; and LP events at Nevado del Ruiz volcano, Colombia. We identified two types of eruption tremor at Tungurahua; noise-like inharmonic waveforms and harmonic oscillatory signals. We found that Is increased linearly with increasing source amplitude for explosion events and LP events, and that Is increased exponentially with increasing source amplitude for inharmonic eruption tremor signals. The source characteristics of harmonic eruption tremor signals differed from those of inharmonic tremor signals. The Is values we estimated for inharmonic eruption tremor were consistent with previous estimates of volumes of tephra fallout. The linear relationship between the source amplitude and Is for LP events can be explained by the wave propagation effects in the diffusion model for multiple scattering assuming a diffusion coefficient of 105 m2/s and an intrinsic Q factor of around 50. The resultant mean free path is approximately 100 m. Our results suggest that Cotopaxi and Nevado del Ruiz volcanoes have similar highly scattering and attenuating structures. Our approach provides a systematic way to compare the size of volcano-seismic signals observed at different volcanoes. The scaling relations among source parameters that we identified

  16. Thermochemical characterization of banana leaves as a potential energy source

    International Nuclear Information System (INIS)

    Highlights: • The chemical composition of semi-dried banana leaves are similar to the other biomass. • The semi-dried leaves present high release of energy under inert and oxidant atmosphere. • The energy released on pyrolysis and combustion can be used to dry the wet banana leaves. • The thermochemical conversion processes can reduce the waste volume significantly. • The banana leaves have potential to use as biomass through combustion and pyrolysis process. - Abstract: Wet and semi-dried banana leaves were characterized through elemental and proximate analyses, lignocellulosic fraction and thermogravimetric analysis (TG/DTG), differential scanning calorimetry (DSC) and high heating value analysis to assess their use as biomass in generating energy through combustion; they were also assessed to determine the potential of obtaining value-added products through pyrolysis. The wet banana leaves had high moisture content of 74.7%. The semi-dried samples exhibited 8.3% moisture, 78.8% volatile solids, 43.5% carbon and a higher heating value of 19.8 MJ/kg. The nitrogen and sulfur contents in the banana leaves were very low. The semi-dried and wet leaves had hemicellulose and lignin contents close to other biomass fuels, and the semi-dried leaves had the lowest cellulose content, of 26.7%. The wet and semi-dried samples showed the same thermal events in oxidizing and inert atmospheres, but with distinctly different mass loss and energy release intensities. The chemical characteristics and the thermal behavior demonstrated by the semi-dried samples indicate their potential for use as biomass, with results similar to other agro-industrial wastes currently used

  17. Single-photon source characterization with infrared-sensitive superconducting single-photon detectors

    CERN Document Server

    Hadfield, R H; Nam, S W; Stevens, M J; Hadfield, Robert H.; Mirin, Richard P.; Nam, Sae Woo; Stevens, Martin J.

    2006-01-01

    Single-photon sources and detectors are key enabling technologies in quantum information processing. Nanowire-based superconducting single-photon detectors (SSPDs) offer single-photon detection from the visible well into the infrared with low dark counts, low jitter and short dead times. We report on the high fidelity characterization (via antibunching and spontaneous emission lifetime measurements) of a cavity-coupled single-photon source at 902 nm using a pair of SSPDs. The twin SSPD scheme reported here is well-suited to the characterization of single-photon sources at telecom wavelengths (1310 nm, 1550 nm).

  18. On using peak amplitude and rise time for AE source characterization

    Indian Academy of Sciences (India)

    M A Majeed; C R L Murthy

    2002-06-01

    Acoustic Emission (AE) signals, which are electrical version of acoustic emissions, are usually analysed using a set of signal parameters. The major objective of signal analysis is to study the characteristics of the sources of emissions. Peak amplitude $(P_a)$ and rise time $(R_t)$ are two such parameters used for source characterization. In this paper, we theoretically investigate the efficiency of $P_a$ and $R_t$ to classify and characterize AE sources by modelling the input stress pulse and transducer. Analytical expressions obtained for $P_a$ and $R_t$ clearly indicate their use and efficiency for source characterization. It is believed that these results may be of use to investigators in areas like control systems and signal processing also.

  19. Performance Characterization of a Solenoid-type Gas Valve for the H- Magnetron Source at FNAL

    Energy Technology Data Exchange (ETDEWEB)

    Sosa, A. [Fermilab; Bollinger, D. S. [Fermilab; Karns, P. R. [Fermilab

    2016-09-06

    The magnetron-style H- ion sources currently in operation at Fermilab use piezoelectric gas valves to function. This kind of gas valve is sensitive to small changes in ambient temperature, which affect the stability and performance of the ion source. This motivates the need to find an alternative way of feeding H2 gas into the source. A solenoid-type gas valve has been characterized in a dedicated off-line test stand to assess the feasibility of its use in the operational ion sources. H- ion beams have been extracted at 35 keV using this valve. In this study, the performance of the solenoid gas valve has been characterized measuring the beam current output of the magnetron source with respect to the voltage and pulse width of the signal applied to the gas valve.

  20. Characterization and source apportionment of fine particulate sources at Rijeka, Croatia from 2013 to 2015

    Science.gov (United States)

    Ivošević, Tatjana; Stelcer, Eduard; Orlić, Ivica; Bogdanović Radović, Iva; Cohen, David

    2016-03-01

    PM2.5 daily aerosol samples were collected in Rijeka, Croatia during period from 6th August 2013 to 29th January 2015. In total, 259 samples were collected on Teflon filters and analyzed by PIXE and PIGE techniques to give information on 21 elements from Na to Pb. Additionally, black carbon was determined with the Laser Integrated Plate Method. Results were statistically evaluated using Positive Matrix Factorization (PMF). Eight major pollution sources: auto, smoke, secondary sulfates, heavy oil combustion, sea spray, road dust, industry iron and soil dust were identified together with their relative contributions in total PM2.5 pollution.

  1. Characterizing, synthesizing, and/or canceling out acoustic signals from sound sources

    Energy Technology Data Exchange (ETDEWEB)

    Holzrichter, John F. (Berkeley, CA); Ng, Lawrence C. (Danville, CA)

    2007-03-13

    A system for characterizing, synthesizing, and/or canceling out acoustic signals from inanimate and animate sound sources. Electromagnetic sensors monitor excitation sources in sound producing systems, such as animate sound sources such as the human voice, or from machines, musical instruments, and various other structures. Acoustical output from these sound producing systems is also monitored. From such information, a transfer function characterizing the sound producing system is generated. From the transfer function, acoustical output from the sound producing system may be synthesized or canceled. The systems disclosed enable accurate calculation of transfer functions relating specific excitations to specific acoustical outputs. Knowledge of such signals and functions can be used to effect various sound replication, sound source identification, and sound cancellation applications.

  2. Vacuum Characterization and Improvement for the Jefferson Lab Polarized Electron Source

    Energy Technology Data Exchange (ETDEWEB)

    Stutzman, Marcy L. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Poelker, Matthew [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Adderley, Philip A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Mamun, Md Abdullah [Old Dominion Univ., Norfolk, VA (United States)

    2015-09-01

    Operating the JLab polarized electron source with high reliability and long lifetime requires vacuum near the XHV level, defined as pressure below 7.5×10-13 Torr. This paper describes ongoing vacuum research at Jefferson Lab including characterization of outgassing rates for surface coatings and heat treatments, ultimate pressure measurements, investigation of pumping including an XHV cryopump, and characterization of ionization gauges in this pressure regime.

  3. A Geometric Approach to Joint Inversion with Applications to Contaminant Source Zone Characterization

    OpenAIRE

    Aghasi, Alireza; Mendoza-Sanchez, Itza; Miller, Eric L.; Ramsburg, C. Andrew; Abriola, Linda M.

    2013-01-01

    This paper presents a new joint inversion approach to shape-based inverse problems. Given two sets of data from distinct physical models, the main objective is to obtain a unified characterization of inclusions within the spatial domain of the physical properties to be reconstructed. Although our proposed method generally applies to many types of inversion problems, the main motivation here is to characterize subsurface contaminant source-zones by processing down gradient hydrological data an...

  4. Characterizing the oxygen isotopic composition of phosphate sources to aquatic ecosystems

    Science.gov (United States)

    Young, M.B.; McLaughlin, K.; Kendall, C.; Stringfellow, W.; Rollog, M.; Elsbury, K.; Donald, E.; Paytan, A.

    2009-01-01

    The oxygen isotopic composition of dissolved inorganic phosphate (δ18Op) in many aquatic ecosystems is not in isotopic equilibrium with ambient water and, therefore, may reflect the source δ18Op. Identification of phosphate sources to water bodies is critical for designing best management practices for phosphate load reduction to control eutrophication. In order for δ18O p to be a useful tool for source tracking, the δ18Op of phosphate sources must be distinguishable from one another; however, the δ18Op of potential sources has not been well characterized. We measured the δ18O p of a variety of known phosphate sources, including fertilizers, semiprocessed phosphorite ore, particulate aerosols, detergents, leachates of vegetation, soil, animal feces, and wastewater treatment plant effluent. We found a considerable range of δ18Op values (from +8.4 to +24.9‰) for the various sources, and statistically significant differences were found between several of the source types. δ18Op measured in three different fresh water systems was generally not in equilibrium with ambient water. Although there is overlap in δ18Op values among the groups of samples, our results indicate that some sources are isotopically distinct and δ18Op can be used for identifying phosphate sources to aquatic systems.

  5. A multi-scale morphological characterization of extended TeV survey sources

    Science.gov (United States)

    Schwarzburg, S.; Pühlhofer, G.; Santangelo, A.

    2012-12-01

    A recurrent topic in very high energy γ-ray astronomy is the morphological characterization of extended sources, which are lacking a clear counterpart in other wavelengths. Whithout a counterpart, the shape of such a source is not known a priori. Therefore blind/unbiased approaches are required to describe such a newly detected source in terms of detached emission regions (``features'') or eventually even separate objects. Ideally, the search takes into account the observation statistic and the instrument response (e.g. the exposure and the point spread function). And finally, a detection significance for the features needs to be provided.

  6. Trace metals in atmospheric particulates characterized of aerosol emitted by industrial and urban sources

    Energy Technology Data Exchange (ETDEWEB)

    Del Borghi, A.; Solisio, C.; Zilli, M.; Del Borghi, M. [Genoa University, Genoa (Italy). Chemical and Process Engineering Institute G.B. Bonino

    1998-12-31

    The results of a year`s study in the Savona area (Italy) for dust deposition have been analyzed in order to characterize the emission sources. The contribution of the major pollutant sources has been determined by tracer metals and their enrichment factors. The selected metals were Cd, Cu, Pb, An, Cr, and Ni. The obtained results show four types of emission sources responsible for airborne trace metals; traffic, industrial plants a large oil and coal fired power station, resuspension of soil particles and residential heating. 9 refs., 9 figs., 1 tab.

  7. Characterization of radioactive orphan sources by gamma spectrometry; Caracterizacion de fuentes huerfanas radiactivas por espectrometria gamma

    Energy Technology Data Exchange (ETDEWEB)

    Cruz W, H., E-mail: wcruz@ipen.gob.pe [Instituto Peruano de Energia Nuclear (PGRR/IPEN), Lima (Peru). Planta de Gestion de Residuos Radiactivos

    2013-07-01

    The sealed radioactive sources are widely applicable in industry. They must have a permanent control and must be registered with the Technical Office of the National Authority (OTAN). However, at times it has identified the presence of abandoned sealed sources unknown to the owner. These sources are called 'orphan sources'. Of course these sources represent a high potential risk because accidents can trigger dire consequences depending on your activity and chemical form in which it presents the radioisotope. This paper describes the process and the actions taken to characterize two orphan radioactive sources from the smelter a Aceros Arequipa. For characterization we used a gamma spectrometry system using a detector NaI(Tl) 3″ x 3″ with a multichannel analyzer Nucleus PCA-II. The radioisotope identified was cesium - 137 ({sup 137}Cs) in both cases. Fortunately, the sources maintained their integrity would otherwise have generated significant pollution considering the chemical form of the radioisotope and easy dispersion. (author)

  8. Correlated Sources in Distributed Networks--Data Transmission, Common Information Characterization and Inferencing

    Science.gov (United States)

    Liu, Wei

    2011-01-01

    Correlation is often present among observations in a distributed system. This thesis deals with various design issues when correlated data are observed at distributed terminals, including: communicating correlated sources over interference channels, characterizing the common information among dependent random variables, and testing the presence of…

  9. Realization and characterization of a 220Rn source for calibration purposes

    International Nuclear Information System (INIS)

    The recent interest for measuring 220Rn activity in air and the following development of the corresponding measurement techniques require the improvement of standards for the calibration and characterization of the measurement devices. Due to the short half-life of the 220Rn, the adopted techniques for the production of 222Rn sources are not always reliable. In this paper a methodology for realizing a thoron known activity starting from a 232Th source will be presented and discussed. - Highlights: • A thoron source realized by well characterized samples containing thorium. • Methodology for measuring exhalated thoron activity by gamma ray spectrometry. • Stable on time thoron specific activity concentration in air. • Radon isotopes spectroscopy by electrostatic collection

  10. Techniques for Source Zone and Plume Characterization of Tetrachloroethene in Fractured Limestone Aquifers

    DEFF Research Database (Denmark)

    Fjordbøge, Annika Sidelmann; Mosthaf, Klaus; Janniche, Gry S.;

    Characterization of chlorinated solvents in fractured limestone aquifers is essential for proper development of site specific conceptual models and subsequent risk assessment and remediation. High resolution characterization is challenged by the difficulties involved in collection of intact core...... samples as water flushing during drilling often results in extensive core losses, especially from zones with soft limestone in contact with flint beds. Field investigations with alternative characterization techniques have been carried out at two Danish sites with tetrachloroethene (PCE) contaminated...... fractured limestone aquifers. The two sites represent different scales (source and plume) and contaminant levels (DNAPL and dissolved). The scope of the investigations was to evaluate different techniques for characterization of the contaminant distribution in the limestone aquifers and to obtain...

  11. Pseudodynamic Source Characterization for Strike-Slip Faulting Including Stress Heterogeneity and Super-Shear Ruptures

    KAUST Repository

    Mena, B.

    2012-08-08

    Reliable ground‐motion prediction for future earthquakes depends on the ability to simulate realistic earthquake source models. Though dynamic rupture calculations have recently become more popular, they are still computationally demanding. An alternative is to invoke the framework of pseudodynamic (PD) source characterizations that use simple relationships between kinematic and dynamic source parameters to build physically self‐consistent kinematic models. Based on the PD approach of Guatteri et al. (2004), we propose new relationships for PD models for moderate‐to‐large strike‐slip earthquakes that include local supershear rupture speed due to stress heterogeneities. We conduct dynamic rupture simulations using stochastic initial stress distributions to generate a suite of source models in the magnitude Mw 6–8. This set of models shows that local supershear rupture speed prevails for all earthquake sizes, and that the local rise‐time distribution is not controlled by the overall fault geometry, but rather by local stress changes on the faults. Based on these findings, we derive a new set of relations for the proposed PD source characterization that accounts for earthquake size, buried and surface ruptures, and includes local rise‐time variations and supershear rupture speed. By applying the proposed PD source characterization to several well‐recorded past earthquakes, we verify that significant improvements in fitting synthetic ground motion to observed ones is achieved when comparing our new approach with the model of Guatteri et al. (2004). The proposed PD methodology can be implemented into ground‐motion simulation tools for more physically reliable prediction of shaking in future earthquakes.

  12. Ultrasonic characterization of the fat source and composition of formulated dry-cured meat products.

    Science.gov (United States)

    Jimenez, Edith Corona; García-Pérez, Jose Vicente; Canillas, Sonia Ventanas; Fort, Jose Javier Benedito

    2014-06-01

    The aim of this work was to test the feasibility of using ultrasonic measurements to estimate the fat content and identify the fat sources used in formulated dry-cured pork meat products. For that purpose, dry-cured sausages were prepared using different fat sources (two Iberian pork backfats, Iberian lard, and sunflower oil) and contents (fat content from 3% to 17% wet basis) and characterized by measuring the ultrasonic velocity (at 2 degrees C, 6 degrees C, 10 degrees C, 15 degrees C, 20 degrees C, and 25 degrees C), fatty acid profile, thermal behavior, and composition. The fatty acid composition affected the melting behavior of the sausages, which also involved different ultrasonic velocities, depending on the fat source used for the sausage formulation. Significant (p sausage batches were differentiated according to the fat source used. The ultrasonic velocity temperature dependence allowed the determination of the fat content (explained variance 96.1%) by measuring the ultrasonic velocity in the dry-cured sausages at 2 degrees C and 25 degrees C and using a semi-empirical equation. Therefore, the ultrasonic measurements could be considered as a reliable tool for the characterization and differentiation of formulated dry-cured meat products with different fat sources and contents.

  13. Characterization and source apportionment of water pollution in Jinjiang River, China.

    Science.gov (United States)

    Chen, Haiyang; Teng, Yanguo; Yue, Weifeng; Song, Liuting

    2013-11-01

    Characterizing water quality and identifying potential pollution sources could greatly improve our knowledge about human impacts on the river ecosystem. In this study, fuzzy comprehensive assessment (FCA), pollution index (PI), principal component analysis (PCA), and absolute principal component score-multiple linear regression (APCS-MLR) were combined to obtain a deeper understanding of temporal-spatial characterization and sources of water pollution with a case study of the Jinjiang River, China. Measurement data were obtained with 17 water quality variables from 20 sampling sites in the December 2010 (withered water period) and June 2011 (high flow period). FCA and PI were used to comprehensively estimate the water quality variables and compare temporal-spatial variations, respectively. Rotated PCA and receptor model (APCS-MLR) revealed potential pollution sources and their corresponding contributions. Application results showed that comprehensive application of various multivariate methods were effective for water quality assessment and management. In the withered water period, most sampling sites were assessed as low or moderate pollution with characteristics pollutants of permanganate index and total nitrogen (TN), whereas 90% sites were classified as high pollution in the high flow period with higher TN and total phosphorus. Agricultural non-point sources, industrial wastewater discharge, and domestic sewage were identified as major pollution sources. Apportionment results revealed that most variables were complicatedly influenced by industrial wastewater discharge and agricultural activities in withered water period and primarily dominated by agricultural runoff in high flow period. PMID:23737126

  14. Concretes characterization for spent radioactive sources; Caracterizacion de concretos para fuentes radiactivas gastadas

    Energy Technology Data Exchange (ETDEWEB)

    Martinez B, J. [Instituto Tecnologico de Saltillo, Venustiano Carranza No. 2400, Col. Tecnologico, 25280 Saltillo, Coahuila (Mexico); Monroy G, F. P., E-mail: jmtzbock@hotmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2013-10-15

    The present work includes the preparation and characterization of the concrete used as conditioning matrix of spent radioactive sources in the Treatment Plant of Radioactive Wastes of the Instituto Nacional de Investigaciones Nucleares (ININ). The concrete tests tubes were subjected to resistance assays to the compression, leaching, resistance to the radiation and porosity, and later on characterized by means of X rays diffraction, scanning electron microscopy and infrared spectrometry, with the purpose of evaluating if this concrete accredits the established tests by the NOM-019-Nucl-1995. The results show that the concrete use in the Treatment Plant fulfills the requirements established by the NOM-019-Nucl-1995. (author)

  15. Optical Microscopy Characterization for Borehole U-15n#12 in Support of NCNS Source Physics Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Jennifer E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sussman, Aviva Joy [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-05-22

    Optical microscopy characterization of thin sections from corehole U-15n#12 is part of a larger material characterization effort for the Source Physics Experiment (SPE). The SPE program was conducted in Nevada with a series of explosive tests designed to study the generation and propagation of seismic waves inside Stock quartz monzonite. Optical microscopy analysis includes the following: 1) imaging of full thin sections (scans and mosaic maps); 2) high magnification imaging of petrographic texture (grain size, foliations, fractures, etc.); and 3) measurement of microfracture density.

  16. Mass spectrometric characterization of a pyrolytic radical source using femtosecond ionization

    Energy Technology Data Exchange (ETDEWEB)

    Frey, H.M.; Beaud, P.; Mischler, B.; Radi, P.P.; Tzannis, A.P.; Gerber, T. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    Radicals play, as reactive species, an important role in the chemistry of combustion. In contrast to atmospheric flames where spectra are congested due to high vibrational and rotational excitation, experiments in the cold environment of a molecular beam (MB) yield clean spectra that can be easily attributed to one species by Resonantly Enhanced Multi Photon Ionization (REMP). A pyrolytic radical source has been set up. To characterize the efficiency of the source `soft` ionization with femto second pulses is applied which results in less fragmentation, simplifying the interpretation of the mass spectrum. (author) figs., tabs., refs.

  17. Extraction and Characterization of Tamarind (Tamarind indica L.) Seed Polysaccharides (TSP) from Three Difference Sources

    OpenAIRE

    Khanittha Chawananorasest; Patsuda Saengtongdee; Praphakorn Kaemchantuek

    2016-01-01

    Tamarind seed polysaccharide (TSP), a natural polysaccharide extracted from tamarind seeds is used in the pharmaceutical, textile and food industries as a mucoadhesive polymer. This work aimed to extract TSP from tamarind seeds from three sources with two methods and characterized its physical and chemical properties. Kernel powder of tamarind seeds was slurried into a clear solution, set aside overnight and then centrifuged at 6000 rpm for 20 min to separate all foreign matter. The supernata...

  18. Genetic Characterization of Escherichia coli Populations from Host Sources of Fecal Pollution by Using DNA Fingerprinting†

    OpenAIRE

    McLellan, Sandra L; Daniels, Annette D.; Salmore, Alissa K.

    2003-01-01

    Escherichia coli isolates were obtained from common host sources of fecal pollution and characterized by using repetitive extragenic palindromic (REP) PCR fingerprinting. The genetic relationship of strains within each host group was assessed as was the relationship of strains among different host groups. Multiple isolates from a single host animal (gull, human, or dog) were found to be identical; however, in some of the animals, additional strains occurred at a lower frequency. REP PCR finge...

  19. RF Phase Stability and Electron Beam Characterization for the PLEIADES Thomson X-Ray Source

    Energy Technology Data Exchange (ETDEWEB)

    Brown, W J; Hartemann, F V; Tremaine, A M; Springer, P T; Le Sage, G P; Barty, C P J; Rosenzweig, J B; Crane, J K; Cross, R R; Fittinghoff, D N; Gibson, D J; Slaughter, D R; Anderson, S

    2002-10-16

    We report on the performance of an S-band RF photocathode electron gun and accelerator for operation with the PLEIADES Thomson x-ray source at LLNL. To produce picosecond, high brightness x-ray pulses, picosecond timing, terahertz bandwidth diagnostics, and RF phase control are required. Planned optical, RF, x-ray and electron beam measurements to characterize the dependence of electron beam parameters and synchronization on RF phase stability are presented.

  20. An approach to source characterization of tremor signals associated with eruptions and lahars

    Science.gov (United States)

    Kumagai, Hiroyuki; Mothes, Patricia; Ruiz, Mario; Maeda, Yuta

    2015-11-01

    Tremor signals are observed in association with eruption activity and lahar descents. Reduced displacement ( D R) derived from tremor signals has been used to quantify tremor sources. However, tremor duration is not considered in D R, which makes it difficult to compare D R values estimated for different tremor episodes. We propose application of the amplitude source location (ASL) method to characterize the sources of tremor signals. We used this method to estimate the tremor source location and source amplitude from high-frequency (5-10 Hz) seismic amplitudes under the assumption of isotropic S-wave radiation. We considered the source amplitude to be the maximum value during tremor. We estimated the cumulative source amplitude ( I s) as the offset value of the time-integrated envelope of the vertical seismogram of tremor corrected for geometrical spreading and medium attenuation in the 5-10-Hz band. For eruption tremor signals, we also estimated the cumulative source pressure ( I p) from an infrasonic envelope waveform corrected for geometrical spreading. We studied these parameters of tremor signals associated with eruptions and lahars and explosion events at Tungurahua volcano, Ecuador. We identified two types of eruption tremor at Tungurahua: noise-like inharmonic waveforms and harmonic oscillatory signals. We found that I s increased linearly with increasing source amplitude for lahar tremor signals and explosion events, but I s increased exponentially with increasing source amplitude for inharmonic eruption tremor signals. The source characteristics of harmonic eruption tremor signals differed from those of inharmonic tremor signals. We found a linear relation between I s and I p for both explosion events and eruption tremor. Because I p may be proportional to the total mass involved during an eruption episode, this linear relation suggests that I s may be useful to quantify eruption size. The I s values we estimated for inharmonic eruption tremor were

  1. Characterization of DNAPL Source Zone Architecture and Prediction of Associated Plume Response: Progress and Perspectives

    Science.gov (United States)

    Abriola, L. M.; Pennell, K. D.; Ramsburg, C. A.; Miller, E. L.; Christ, J.; Capiro, N. L.; Mendoza-Sanchez, I.; Boroumand, A.; Ervin, R. E.; Walker, D. I.; Zhang, H.

    2012-12-01

    It is now widely recognized that the distribution of contaminant mass will control both the evolution of aqueous phase plumes and the effectiveness of many source zone remediation technologies at sites contaminated by dense nonaqueous phase liquids (DNAPLs). Advances in the management of sites containing DNAPL source zones, however, are currently hampered by the difficulty associated with characterizing subsurface DNAPL 'architecture'. This presentation provides an overview of recent research, integrating experimental and mathematical modeling studies, designed to improve our ability to characterize DNAPL distributions and predict associated plume response. Here emphasis is placed on estimation of the most information-rich DNAPL architecture metrics, through a combination of localized in situ tests and more readily available plume transect concentration observations. Estimated metrics will then serve as inputs to an upscaled screening model for prediction of long term plume response. Machine learning techniques were developed and refined to identify a variety of source zone metrics and associated confidence intervals through the processing of down gradient concentration data. Estimated metrics include the volumes and volume percentages of DNAPL in pools and ganglia, as well as their ratio (pool fraction). Multiphase flow and transport simulations provided training data for model development and assessment that are representative of field-scale DNAPL source zones and their evolving plumes. Here, a variety of release and site heterogeneity (sequential Gaussian permeability) conditions were investigated. Push-pull tracer tests were also explored as a means to provide localized in situ observations to refine these metric estimates. Here, two-dimensional aquifer cell experiments and mathematical modeling were used to quantify upscaled interphase mass transfer rates and the interplay between injection and extraction rates, local source zone architecture, and tracer

  2. Biotechnological Production of Docosahexaenoic Acid Using Aurantiochytrium limacinum: Carbon Sources Comparison And Growth Characterization

    Directory of Open Access Journals (Sweden)

    Sergi Abad

    2015-12-01

    Full Text Available Aurantiochytrium limacinum, a marine heterotrophic protist/microalga has shown interesting yields of docosahexaenoic acid (DHA when cultured with different carbon sources: glucose, pure and crude glycerol. A complete study in a lab-scale fermenter allowed for the characterization and comparison of the growth kinetic parameters corresponding to each carbon source. Artificial Marine Medium (AMM with glucose, pure and crude glycerol offered similar biomass yields. The net growth rates (0.10–0.12 h−1, biomass (0.7–0.8 g cells/g Substrate and product (0.14–0.15 g DHA/g cells yields, as well as DHA productivity were similar using the three carbon sources. Viable potential applications to valorize crude glycerol are envisioned to avoid an environmental problem due to the excess of byproduct.

  3. Characterization of a radiographic system with broad energy band X-ray source

    International Nuclear Information System (INIS)

    High energy X-ray beams with broad band energy spectra allow performing radiographic analysis on different materials and objects of relevant interest that cannot be investigated with conventional X-ray sources. The quality of a radiographic image strongly depends on the characteristics of radiation source as the size of the X-ray emitting area, or focal spot, and the energy spectrum of the radiation. In this work the characterization of a broad-band energy Bremsstrahlung source obtained from a linac providing a 5.5 MeV electron beam colliding with a tungsten target is presented. In order to measure the focal-spot size an ad hoc slit camera has been designed and built and a specific technique was used. Furthermore an analysis of the energy spectrum of the beam was performed using a method based on X-ray diffraction by a mosaic crystal.

  4. Chemical characterization and source apportionment of PM2.5 in Beijing: seasonal perspective

    Directory of Open Access Journals (Sweden)

    R. Zhang

    2013-07-01

    Full Text Available In this study, 121 daily PM2.5 (aerosol particle with aerodynamic diameter less than 2.5 μm samples were collected from an urban site in Beijing in four months between April 2009 and January 2010 representing the four seasons. The samples were determined for various compositions, including elements, ions, and organic/elemental carbon. Various approaches, such as chemical mass balance, positive matrix factorization (PMF, trajectory clustering, and potential source contribution function (PSCF, were employed for characterizing aerosol speciation, identifying likely sources, and apportioning contributions from each likely source. Our results have shown distinctive seasonality for various aerosol speciations associated with PM2.5 in Beijing. Soil dust waxes in the spring and wanes in the summer. Regarding the secondary aerosol components, inorganic and organic species may behave in different manners. The former preferentially forms in the hot and humid summer via photochemical reactions, although their precursor gases, such as SO2 and NOx, are emitted much more in winter. The latter seems to favorably form in the cold and dry winter. Synoptic meteorological and climate conditions can overwhelm the emission pattern in the formation of secondary aerosols. The PMF model identified six main sources: soil dust, coal combustion, biomass burning, traffic and waste incineration emission, industrial pollution, and secondary inorganic aerosol. Each of these sources has an annual mean contribution of 16, 14, 13, 3, 28, and 26%, respectively, to PM2.5. However, the relative contributions of these identified sources significantly vary with changing seasons. The results of trajectory clustering and the PSCF method demonstrated that regional sources could be crucial contributors to PM pollution in Beijing. In conclusion, we have unraveled some complex aspects of the pollution sources and formation processes of PM2.5 in Beijing. To our knowledge, this is the first

  5. Chemical characterization and source apportionment of PM2.5 in Beijing: seasonal perspective

    Directory of Open Access Journals (Sweden)

    R. Zhang

    2013-04-01

    Full Text Available In this study, 121 daily PM2.5 (aerosol particle with aerodynamic diameter less than 2.5 μm samples were collected from an urban site in Beijing in four months between April 2009 and January 2010 representing the four seasons. The samples were determined for various compositions, including elements, ions, and organic/elemental carbon. Various approaches, such as chemical mass balance, positive matrix factorization (PMF, trajectory clustering, and potential source contribution function (PSCF, were employed for characterizing aerosol speciation, identifying likely sources, and apportioning contributions from each likely source. Our results have shown distinctive seasonalities for various aerosol speciations associated with PM2.5 in Beijing. Soil dust waxes in the spring and wanes in the summer. Regarding the secondary aerosol components, inorganic and organic species may behave in different manners. The former preferentially forms in the hot and humid summer via photochemical reactions, although their precursor gases, such as SO2 and NOx, are emitted much more in winter. The latter seems to favorably form in the cold and dry winter. Synoptic meteorological and climate conditions can overwhelm the emission pattern in the formation of secondary aerosols. The PMF model identified six main sources: soil dust, coal combustion, biomass burning, traffic and waste incineration emission, industrial pollution, and secondary inorganic aerosol. Each of these sources has an annual mean contribution of 16, 14, 13, 3, 28, and 26%, respectively, to PM2.5. However, the relative contributions of these identified sources significantly vary with changing seasons. The results of trajectory clustering and the PSCF method demonstrated that regional sources could be crucial contributors to PM pollution in Beijing. In conclusion, we have unraveled some complex aspects of the pollution sources and formation processes of PM2.5 in Beijing. To our knowledge, this study is

  6. Chemical characterization and source apportionment of PM2.5 in Beijing: seasonal perspective

    Science.gov (United States)

    Zhang, R.; Jing, J.; Tao, J.; Hsu, S.-C.; Wang, G.; Cao, J.; Lee, C. S. L.; Zhu, L.; Chen, Z.; Zhao, Y.; Shen, Z.

    2013-07-01

    In this study, 121 daily PM2.5 (aerosol particle with aerodynamic diameter less than 2.5 μm) samples were collected from an urban site in Beijing in four months between April 2009 and January 2010 representing the four seasons. The samples were determined for various compositions, including elements, ions, and organic/elemental carbon. Various approaches, such as chemical mass balance, positive matrix factorization (PMF), trajectory clustering, and potential source contribution function (PSCF), were employed for characterizing aerosol speciation, identifying likely sources, and apportioning contributions from each likely source. Our results have shown distinctive seasonality for various aerosol speciations associated with PM2.5 in Beijing. Soil dust waxes in the spring and wanes in the summer. Regarding the secondary aerosol components, inorganic and organic species may behave in different manners. The former preferentially forms in the hot and humid summer via photochemical reactions, although their precursor gases, such as SO2 and NOx, are emitted much more in winter. The latter seems to favorably form in the cold and dry winter. Synoptic meteorological and climate conditions can overwhelm the emission pattern in the formation of secondary aerosols. The PMF model identified six main sources: soil dust, coal combustion, biomass burning, traffic and waste incineration emission, industrial pollution, and secondary inorganic aerosol. Each of these sources has an annual mean contribution of 16, 14, 13, 3, 28, and 26%, respectively, to PM2.5. However, the relative contributions of these identified sources significantly vary with changing seasons. The results of trajectory clustering and the PSCF method demonstrated that regional sources could be crucial contributors to PM pollution in Beijing. In conclusion, we have unraveled some complex aspects of the pollution sources and formation processes of PM2.5 in Beijing. To our knowledge, this is the first systematic study

  7. Radiological Characterization Technical Report on Californium-252 Sealed Source Transuranic Debris Waste for the Off-Site Source Recovery Project at Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Feldman, Alexander [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-04-24

    This document describes the development and approach for the radiological characterization of Cf-252 sealed sources for shipment to the Waste Isolation Pilot Plant. The report combines information on the nuclear material content of each individual source (mass or activity and date of manufacture) with information and data on the radionuclide distributions within the originating nuclear material. This approach allows for complete and accurate characterization of the waste container without the need to take additional measurements. The radionuclide uncertainties, developed from acceptable knowledge (AK) information regarding the source material, are applied to the summed activities in the drum. The AK information used in the characterization of Cf-252 sealed sources has been qualified by the peer review process, which has been reviewed and accepted by the Environmental Protection Agency.

  8. Background electromagnetic noise characterization: the role of external and internal Earth sources

    Directory of Open Access Journals (Sweden)

    Antonio Meloni

    2015-07-01

    Full Text Available The Earth is surrounded by the ionosphere and magnetosphere that can roughly be seen schematically as two concentric shells. These two composed and inhomogeneous structured shells around the Earth selectively affect electromagnetic (EM waves propagation. Both ionosphere and magnetosphere interact also with particles and waves coming from external sources, generating electromagnetic phenomena that in turn might become sources of EM waves. Conversely, EM waves generated inside the ionosphere remain confined at various altitudes in this region, up to a so-called critical frequency limit, depending on frequency, EM waves can escape out of the ionosphere and magnetosphere or get through. The EM waves generated inside the magnetospheric cavity mainly originate as a result of the electrical activity in the atmosphere. It is well known that also man-made sources, now widely spread on Earth, are a fundamental source of EM waves; however, excluding certain frequencies employed in power distribution and communication, man-made noise can be dominant only at local scale, near their source. According to recent studies, EM waves are also generated in the Earth’s lithosphere; these waves were sometimes associated with earthquake activity showing, on the Earth’s surface, intensities that are generally orders of magnitude below the background EM noise. In this review paper, we illustrate EM waves of natural origin and discuss their characterization in order to try discriminate those of lithospheric origin detectable at or near the Earth’s surface.

  9. Progress in characterizing the multidimensional color quality properties of white LED light sources

    Science.gov (United States)

    Teunissen, Kees; Hoelen, Christoph

    2016-03-01

    With the introduction of solid state light sources, the variety in emission spectra is almost unlimited. However, the set of standardized parameters to characterize a white LED light source, such as correlated color temperature (CCT) and CIE general color rendering index (Ra), is known to be limited and insufficient for describing perceived differences between light sources. Several characterization methods have been proposed over the past decades, but their contribution to perceived color quality has not always been validated. To gain more insight in the relevant characteristics of the emission spectra for specific applications, we have conducted a perception experiment to rate the attractiveness of three sets of objects, including fresh food, packaging materials and skin tones. The objects were illuminated with seven different combinations of Red, Green, Blue, Amber and White LEDs, all with the same CCT and illumination level, but with differences in Ra and color saturation. The results show that, in general, object attractiveness does not correlate well with Ra, but shows a positive correlation with saturation increase for two out of three applications. There is no clear relation between saturation and skin tone attractiveness, partly due to differences in preference between males and females. A relative gamut area index (Ga) represents the average change in saturation and a complementary color vector graphic shows the direction and magnitude of chromatic differences for the eight CIE-1974 test-color samples. Together with the CIE general color rendering index (Ra) they provide useful information for designing and optimizing application specific emission spectra.

  10. Spectro-photometric characterization of high proper motion sources from WISE

    CERN Document Server

    Beamín, J C; Minniti, D; Smart, R L; Muzic, K; Mendez, R A; Beletsky, Y; Bayo, A; Gromadzki, M; Kurtev, R

    2015-01-01

    The census of the solar neighborhood is almost complete for stars and becoming more complete in the brown dwarf regime. Spectroscopic, photometric and kinematic characterization of nearby objects helps us to understand the local mass function, the binary fraction, and provides new targets for sensitive planet searches. We aim to derive spectral types and spectro-photometric distances of a sample of new high proper motion sources found with the WISE satellite, and obtain parallaxes for those objects that fall within the area observed by the Vista Variables in the V\\'ia L\\'actea survey (VVV). We used low resolution spectroscopy and template fitting to derive spectral types, multiwavelength photometry to characterize the companion candidates and obtain photometric distances. Multi-epoch imaging from the VVV survey was used to measure the parallaxes and proper motions for three sources. We confirm a new T2 brown dwarf within $\\sim$15 pc. We derived optical spectral types for twenty four sources, mostly M dwarfs w...

  11. Oscillatory Hydraulic Tomography for NAPL Source Zone Characterization: Sandbox Experiment Demonstration

    Science.gov (United States)

    Cardiff, M. A.; Zhou, Y.

    2015-12-01

    Characterizing the distribution and extent of NAPL contamination is an important step in determining appropriate remedial actions. NAPL has a complex mode of transportation in the heterogeneous subsurface domain, which results in difficulties for cleaning up contaminated sites. Here, we use sandbox experiments to demonstrate the effectiveness of Oscillatory Hydraulic Tomography (OHT) for NAPL source zone characterization. In a saturated soil fluid system, the effective hydraulic conductivity (K) is dependent on the soil properties, fluid density, and fluid viscosity. By taking advantage of the differences of fluid properties before and after NAPL intrusion, we can estimate the NAPL source zone migration throughout time by imaging changes in effective K. Using OHT testing, we can derive the K heterogeneities before, during and after NAPL intrusion. NAPL source zone can be located by subtracting the background K from the K tomogram after NAPL intrusion. This approach can avoid mass extraction and injection that occurs in traditional hydraulic tomography approaches while obtain a good estimation of subsurface K heterogeneity and NAPL migration. We believe this method is more cost effective and efficient for field remediation applications.

  12. Strategies for lidar characterization of particulates from point and area sources

    Science.gov (United States)

    Wojcik, Michael D.; Moore, Kori D.; Martin, Randal S.; Hatfield, Jerry

    2010-10-01

    Use of ground based remote sensing technologies such as scanning lidar systems (light detection and ranging) has gained traction in characterizing ambient aerosols due to some key advantages such as wide area of regard (10 km2), fast response time, high spatial resolution (sources in agricultural and industrial settings. A suite of massbased and size distribution point sensors are used to locally calibrate the lidar. Generating meaningful particle size distribution, mass concentration, and emission rate results based on lidar data is dependent on strategic onsite deployment of these point sensors with successful local meteorological measurements. Deployment strategies learned from field use of this entire measurement system over five years include the characterization of local meteorology and its predictability prior to deployment, the placement of point sensors to prevent contamination and overloading, the positioning of the lidar and beam plane to avoid hard target interferences, and the usefulness of photographic and written observational data.

  13. A Geometric Approach to Joint Inversion with Applications to Contaminant Source Zone Characterization

    CERN Document Server

    Aghasi, Alireza; Miller, Eric L; Ramsburg, C Andrew; Abriola, Linda M

    2013-01-01

    This paper presents a new joint inversion approach to shape-based inverse problems. Given two sets of data from distinct physical models, the main objective is to obtain a unified characterization of inclusions within the spatial domain of the physical properties to be reconstructed. Although our proposed method generally applies to many types of inversion problems, the main motivation here is to characterize subsurface contaminant source-zones by processing down gradient hydrological data and cross-gradient electrical resistance tomography (ERT) observations. Inspired by Newton's method for multi-objective optimization, we present an iterative inversion scheme that suggests taking descent steps that can simultaneously reduce both data-model misfit terms. Such an approach, however, requires solving a non-smooth convex problem at every iteration, which is computationally expensive for a pixel-based inversion over the whole domain. Instead, we employ a parametric level set (PaLS) technique that substantially re...

  14. SiC detectors for radiation sources characterization and fast plasma diagnostic

    Science.gov (United States)

    Cannavò, A.; Torrisi, L.

    2016-09-01

    Semiconductor detectors based on SiC have been investigated to characterize the radiations (photons and particles) emitted from different sources, such as radioactive sources, electron guns, X-ray tubes and laser-generated plasmas. Detectors show high response velocity, low leakage current, high energy gap and high radiation hardness. Their high detection efficiency permits to use the detectors in spectroscopic mode and in time-of-flight (TOF) approach, generally employed to monitor low and high radiation fluxes, respectively. Using the laser start signal, they permit to study the properties of the generated plasma in vacuum by measuring accurately the particle velocity and energy using pulsed lasers at low and high intensities. Possible applications will be reported and discussed.

  15. Integrated Characterization of DNAPL Source Zone Architecture in Clay Till and Limestone Bedrock

    DEFF Research Database (Denmark)

    Broholm, Mette Martina; Janniche, Gry Sander; Fjordbøge, Annika Sidelmann;

    2014-01-01

    . The activities of a distribution facility for perchloroethene (PCE) and trichloroethene (TCE) at the Naverland site near Copenhagen, Denmark, has resulted in PCE and TCE DNAPL impacts to a fractured clay till and an underlying fractured limestone aquifer/bedrock. The scope of the investigations was to evaluate...... innovative investigation methods and characterize the source zone hydrogeology and contamination to obtain an improved conceptual understanding of DNAPL source zone architecture in clay till and bryozoan limestone bedrock. Approach/Activities. A wide range of innovative and current site investigative tools...... the conceptual understanding of transport and distribution of DNAPL in the fill and clayey till and the interface to the limestone. Core loss in the limestone, particulary from soft zones in contact with flint beds, was caused by the water flush applied during drilling and likely also resulted in loss of DNAPL...

  16. Characterization and application of a laser-driven intense pulsed neutron source using Trident

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, Sven C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-25

    A team of Los Alamos researchers supported a final campaign to use the Trident laser to produce neutrons, contributed their multidisciplinary expertise to experimentally assess if laser-driven neutron sources can be useful for MaRIE. MaRIE is the Laboratory’s proposed experimental facility for the study of matter-radiation interactions in extremes. Neutrons provide a radiographic probe that is complementary to x-rays and protons, and can address imaging challenges not amenable to those beams. The team's efforts characterize the Laboratory’s responsiveness, flexibility, and ability to apply diverse expertise where needed to perform successful complex experiments.

  17. Solvothermal Synthesis and Characterization of HgTe Nanoplatelets Using Mercury(Ⅰ) Source

    Institute of Scientific and Technical Information of China (English)

    WU Ke-Jun; WANG Ming-Sheng; ZOU Jian-Ping; XU Gang; DING Tong-Yong; GUO Guo-Cong; HUANG Jin-Shun

    2008-01-01

    Mercury telluride (HgTe) nanoplatelets were obtained via a facile solvothermal reaction of mercury(Ⅰ) chloride and tellurium powder in ethylenediamine (en). Mercury(Ⅰ) was first applied as the mercury sources to prepare nanocrystal HgTe; moreover, the proposed mechanism for the fabrication of the sample was discussed in detail. The HgTe nanoplatelets were characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM),transmission electron microscopy (TEM), high-resolution transmission electron microscopy(HRTEM) and Fourier transform infrared spectroscopy (FT-IR). The absence of IR absorption may render the title nanocrystal useful as an IR transparent material in the region.

  18. Characterization and application of a laser-driven intense pulsed neutron source using Trident

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, Sven C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-25

    A team of Los Alamos researchers supported a final campaign to use the Trident laser to produce neutrons, contributed their multidisciplinary expertise to experimentally assess if laser-driven neutron sources can be useful for MaRIE. MaRIE is the Laboratory’s proposed experimental facility for the study of matter-radiation interactions in extremes. Neutrons provide a radiographic probe that is complementary to x-rays and protons, and can address imaging challenges not amenable to those beams. The teams efforts characterize the Laboratory’s responsiveness, flexibility, and ability to apply diverse expertise where needed to perform successful complex experiments.

  19. Device characterization of the VCSEL-on-silicon as an on chip light source

    Science.gov (United States)

    Kwack, Myung-Joon; Jang, Ki-Seok; Joo, Jiho; Park, Hyundai; Oh, Jin Hyuk; Park, Jaegyu; Kim, Sanggi; Kim, Gyungock

    2016-03-01

    Advancement of silicon photonics technology can offer a new dimension in data communications with un-precedent bandwidth. Increasing the integration level in the silicon photonics is required to develop compact high-performance chip-level optical interconnects for future systems. Especially, monolithic integration of light source on a silicon wafer is important for future silicon photonic integrated circuits, since realizing a compact on-chip light source on a silicon wafer is a serious issue which impedes practical implementation of the silicon photonic interconnects. At present, due to the lack of a practical light source based on Group IV elements, flip chip-bonded or packaged lasers based on III-V semiconductor are usually being used as external light sources, to feed silicon modulators on SOI wafers to complete a photonic transmitter, except the reported silicon hybrid lasers monolithic-integrated on SOI wafers. To overcome above problem, we have proposed a compact on-chip light source, the directly monolithic-integrated VCSEL on a bulk silicon wafer (VCSEL-on-Si), based on the transplanted epitaxial film by substrate lift-off process and following device-fabrication on the bulk Si wafer. This can offer practical low-power-consumption light sources integrated on a silicon wafer, which can provide a complete chip-level I/O set when combined with monolithic-integrated vertical-illumination Ge-on-Si photodetectors on the same silicon wafer. In this work, we report the characterization of direct-modulation VCSELs-on-Si for λ ~850 nm with CW optical output power > ~2 mW and the threshold current < ~3 mA, over 10 Gb/s operations. We also discuss about the thermal characteristics of the VCSELs-on-Si.

  20. Characterization of a 137Cs standard source for calibration purposes ar CRCN-NE

    International Nuclear Information System (INIS)

    Radiation protection monitoring instruments should be calibrated by accredited calibration laboratories. To offer calibration services, a laboratory must accomplish all requirements established by the national regulatory agency. The Calibration Service of the Centro Regional de Ciencias Nucleares (CRCN-NE), Comissao Nacional de Energia Nuclear, Recife, Brazil, is trying to achieve this accreditation. In the present work, a 137Cs standard source was characterized following the national and international recommendations and the results are presented. This source is a commercially available single source irradiator model 28-8A, manufactured by JLShepherd and Associates, with initial activity of 444 GBq (05/13/03). To provide different air kerma rates, as required for the calibration of portable radiation monitors, this irradiator have a set of four lead attenuators with different thickness, providing attenuation factors equal to 2, 4, 10 and 100 times (nominally). The performed tests included: size and uniformity of the radiation standard field at calibration reference position, variation of the air kerma rate for different lead attenuators, determination of attenuation factors for each lead attenuator configuration, and determination of the radiation scattering at the calibration reference position. The results showed the usefulness of the 137Cs standard source for the calibration of radiation protection monitoring detectors. (author)

  1. Evaluation and characterization of General Purpose Heat Source girth welds for the Cassini mission

    International Nuclear Information System (INIS)

    General Purpose Heat Sources (GPHSs) are components of Radioisotopic thermoelectric Generators (RTGs) which provide electric power for deep space missions. Each GPHS consists of a 238Pu oxide ceramic pellet encapsulated in a welded iridium alloy shell which forms a protective barrier against the release of plutonia in the unlikely event of a launch-pad failure or reentry incident. GPHS fueled clad girth weld flaw detection was paramount to ensuring this safety function, and was accomplished using both destructive and non-destructive evaluation techniques. The first girth weld produced from each welding campaign was metallographically examined for flaws such as incomplete weld penetration, cracks, or porosity which would render a GPHS unacceptable for flight applications. After an acceptable example weld was produced, the subsequently welded heat sources were evaluated non-destructively for flaws using ultrasonic immersion testing. Selected heat sources which failed ultrasonic testing would be radiographed, and/or, destructively evaluated to further characterize and document anomalous indications. Metallography was also performed on impacted heat sources to determine the condition of the welds

  2. Common-source TLD and RADFET characterization of Co-60, Cs-137, and x-ray irradiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Simons, M. [Research Triangle Inst., Research Triangle Park, NC (United States); Pease, R.L. [RLP Research, Albuquerque, NM (United States); Fleetwood, D.M. [Sandia National Labs., Albuquerque, NM (United States)] [and others

    1997-06-01

    Dose enhancement and dose rate were measured in more than a dozen gamma sources using pMOS RADFETs and TLDs from two independent sources. ARACOR X-ray dose rates were calibrated using single- and dual-dielectric RADFETs.

  3. Self characterization of a coded aperture array for neutron source imaging

    International Nuclear Information System (INIS)

    The neutron imaging system at the National Ignition Facility (NIF) is an important diagnostic tool for measuring the two-dimensional size and shape of the neutrons produced in the burning deuterium-tritium plasma during the stagnation stage of inertial confinement fusion implosions. Since the neutron source is small (∼100 μm) and neutrons are deeply penetrating (>3 cm) in all materials, the apertures used to achieve the desired 10-μm resolution are 20-cm long, triangular tapers machined in gold foils. These gold foils are stacked to form an array of 20 apertures for pinhole imaging and three apertures for penumbral imaging. These apertures must be precisely aligned to accurately place the field of view of each aperture at the design location, or the location of the field of view for each aperture must be measured. In this paper we present a new technique that has been developed for the measurement and characterization of the precise location of each aperture in the array. We present the detailed algorithms used for this characterization and the results of reconstructed sources from inertial confinement fusion implosion experiments at NIF

  4. A New Approach to Characterizing Landslide Hazards with Global Crowd Sourcing

    Science.gov (United States)

    Bach Kirschbaum, D.; Cappelaere, P. G.; Stanley, T.; Hall, B.; Franchek, M.

    2014-12-01

    Landslide disasters cause thousands of fatalities each year and cumulatively produce more economic damage than most other natural disasters. However, the number and distribution of landslides remain poorly quantified due to their small size and the absence of local, regional or global observing or reporting mechanisms. As a result, there are very few global databases that describe landslide hazards. Characterizing the socioeconomic impacts of landslide hazards worldwide presents an even more challenging task due to the various reporting biases or information gaps in existing regional and global sources. An online system has been developed to improve reporting of landslide hazards at the global scale that leverages crowd sourcing capabilities. Through this portal, users are able to input landslide information in a series of specified fields, including the date, location, impacts, trigger, and setting of the event. They are also able to link to photos so that other users can improve the characterization of the landslide event based on additional information or expert opinion. This hazard portal and editor provides a foundation to involve citizens in reporting, visualizing and sharing landslide events while improving a global landslide database and introducing them to other geospatial data in the process. A global landslide catalog of over 6,000 events developed at NASA Goddard Space Flight Center currently anchors this system. This research presents this new crowd-based system and outlines the technology used in developing this system. Preliminary findings of societal metrics, limitations on this type of interactive crowd sourcing portal, and lessons learned from the initial launch of this system will also be presented.

  5. Thermal Nondestructive Characterization of Corrosion in Boiler Tubes by Application fo a Moving Line Heat Source

    Science.gov (United States)

    Cramer, K. Elliott; Winfree, William P.

    2000-01-01

    Wall thinning in utility boiler waterwall tubing is a significant inspection concern for boiler operators. Historically, conventional ultrasonics has been used lor inspection of these tubes. This technique has proved to be very labor intensive and slow. This has resulted in a "spot check" approach to inspections, making thickness measurements over a relatively small percentage of the total boiler wall area. NASA Langley Research Center has developed a thermal NDE technique designed to image and quantitatively characterize the amount of material thinning present in steel tubing. The technique involves the movement of a thermal line source across the outer surface of the tubing followed by an infrared imager at a fixed distance behind the line source. Quantitative images of the material loss due to corrosion are reconstructed from measurements of the induced surface temperature variations. This paper will present a discussion of the development of the thermal imaging system as well as the techniques used to reconstruct images of flaws. The application of the thermal line source, coupled with this analysis technique, represents a significant improvement in the inspection speed for large structures such as boiler waterwalls while still providing high-resolution thickness measurements. A theoretical basis for the technique will be presented thus demonstrating the quantitative nature of the technique. Further, results of laboratory experiments on flat Panel specimens with fabricated material loss regions will be presented.

  6. Design and characterization of the annular cathode high current pulsed electron beam source for circular components

    Science.gov (United States)

    Jiang, Wei; Wang, Langping; Wang, Xiaofeng

    2016-08-01

    In order to irradiate circular components with high current pulsed electron beam (HCPEB), an annular cathode based on carbon fiber bunches was designed and fabricated. Using an acceleration voltage of 25 kV, the maximum pulsed irradiation current and energy of this annular cathode can reach 7.9 kA and 300 J, respectively. The irradiation current density distribution of the annular cathode HCPEB source measured along the circumferential direction shows that the annular cathode has good emission uniformity. In addition, four 9310 steel substrates fixed uniformly along the circumferential direction of a metal ring substrate were irradiated by this annular cathode HCPEB source. The surface and cross-section morphologies of the irradiated samples were characterized by scanning electron microscopy (SEM). SEM images of the surface reveal that crater and surface undulation have been formed, which hints that the irradiation energy of the HCPEB process is large enough for surface modification of 9310 steel. Meanwhile, SEM cross-section images exhibit that remelted layers with a thickness of about 5.4 μm have been obtained in all samples, which proves that a good practical irradiation uniformity can be achieved by this annular cathode HCPEB source.

  7. Characterization of HDR Ir-192 source for 3D planning system

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, Gabriel P.; Yoriyaz, Helio; Antunes, Paula C.G.; Siqueira, Paulo T.D., E-mail: gabriel.fonseca@usp.b, E-mail: hyoriyaz@ipen.b, E-mail: ptsiquei@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Rubo, Rodrigo [Universidade de Sao Paulo (HC/FMUSP), Sao Paulo, SP (Brazil). Hospital das Clinicas. Servico de Radioterapia; Minamisawa, Renato A., E-mail: renato.minamisawa@psi.c [Paul Scherrer Institut (PSI), Villigen (Switzerland); Ferreira, Louise A. [Universidade Estadual de Maringa (UEM), PR (Brazil). Fac. de Medicina

    2011-07-01

    Brachytherapy treatment involves surgical or cavitary insertion of radioactive sources for diseases treatments, such as: lung, gynecologic or prostate cancer. This technique has great ability to administer high doses to the tumor, with adjacent normal tissue preservation equal or better than external beam radiation therapy. Several innovations have been incorporated in this treatment technique, such as, 3D treatment planning system and computer guided sources. In detriment to scientific advances there are no protocols that relate dose with tumor volume, organs or A point, established by ICRU38 and used to prescribe dose in treatment planning system. Several international studies, like as EMBRACE, the multicentre international study, has been trying to correlate the dose volume using 3D planning systems and medical images, as those obtained by CT or MRI, to establish treatment protocols. With the objective of analyzing the 3D dose distribution, a micro Selectron-HDR remote afterloading device for high dose-rate (HDR) was characterized in the present work. Through the data provided by the manufacturer the source was simulated, using the MCNP5 code to calculate American Association of Physicists in Medicine Task Group No. 43 report (AAPM TG43) specified parameters. The simulations have shown great agreement when compared to the ONCENTRA planning system results and those provided by literature. The micro Selectron-HDR remote afterloading device will be utilized to simulate 3D dose distribution through CT images processed by an auxiliary software which process DICOM images. (author)

  8. Thermographic detection and quantitative characterization of corrosion by application of thermal line source

    Science.gov (United States)

    Cramer, K. Elliott; Winfree, William P.; Reid, Dan; Johnson, Jane

    1999-02-01

    Wall thinning in utility boiler waterwall tubing is a significant inspection concern for boiler operators. Historically, conventional ultrasonics has been used for inspection of these tubes. This technique has proved to be very labor intensive and slow. This has resulted in a `spot check' approach to inspections, making thickness measurements over a relatively small percentage of the total boiler wall area. NASA Langley Research Center has developed a thermal NDE technique designed to image and quantitatively characterize the amount of material thinning present in steel tubing. The technique involves the movement of a thermal line source across the outer surface of the tubing followed by an infrared imager at a fixed distance behind the line source. Quantitative images of the material loss due to corrosion are reconstructed from measurements of the induced surface temperature variations. This paper will present a discussion of the development of the thermal imaging system as well as the techniques used to reconstruct images of flaws. The application of the thermal line source, coupled with this analysis technique, represents a significant improvement in the inspection speed for large structures such as boiler waterwalls while still providing high-resolution thickness measurements. A theoretical basis for the technique will be presented thus demonstrating the quantitative nature of the technique. Further, results of laboratory experiments on flat panel specimens with fabricated material loss regions will be presented to demonstrate the capabilities of the technique. Additionally, the results of applying this technology to actual waterwall tubing samples will be presented.

  9. Characterization techniques for the high-brightness particle beams of the Advanced Photon Source (APS)

    Energy Technology Data Exchange (ETDEWEB)

    Lumpkin, A.H.

    1993-08-01

    The Advanced Photon Source (APS) will be a third-generation synchrotron radiation (SR) user facility in the hard x-ray regime (10--100 keV). The design objectives for the 7-GeV storage ring include a positron beam natural emittance of 8 {times} 10{sup {minus}9} m-rad at an average current of 100 mA. Proposed methods for measuring the transverse and longitudinal profiles will be described. Additionally, a research and development effort using an rf gun as a low-emittance source of electrons for injection into the 200- to 650-MeV linac subsystem is underway. This latter system is projected to produce electron beams with a normalized, rms emittance of {approximately}2 {pi} mm-mrad at peak currents of near one hundred amps. This interesting characterization problem will also be briefly discussed. The combination of both source types within one laboratory facility will stimulate the development of diagnostic techniques in these parameter spaces.

  10. Characterization of a laser-plasma extreme-ultraviolet source using a rotating cryogenic Xe target

    Science.gov (United States)

    Amano, S.; Masuda, K.; Shimoura, A.; Miyamoto, S.; Mochizuki, T.

    2010-10-01

    A laser-plasma source for extreme-ultraviolet (EUV) light that uses a rotating cryogenic solid-state Xe target has been characterized. We focused on parameters at the wavelength of 13.5 nm with 2% bandwidth required for an EUV lithography source and investigated improvements of the conversion efficiency (CE). With the drum rotating, there was an increase in CE and less fast ions compared with the case for the drum at rest. It is considered that the Xe gas on the target surface can produce optimal-scale plasma, and satellite emission lines in Xe plasma effectively increase the EUV intensity, and the ion number is decreased by the gas curtain effect. The dependence of CE on the laser wavelength, laser energy and intensity also studied. As a result, the maximum CE was 0.9% at 13.5 nm with 2% bandwidth under the optimal condition. By continuous irradiation of a Nd:YAG slab laser at a repetition rate of 320 Hz and an average power of 110 W, the target continuously generated EUV light with an average power of 1 W at 13.5 nm with 2% bandwidth. The achieved performances provide valuable information for the design of a future EUV lithography source.

  11. Chemical characterization of fine organic aerosol for source apportionment at Monterrey, Mexico

    Science.gov (United States)

    Mancilla, Y.; Mendoza, A.; Fraser, M. P.; Herckes, P.

    2015-07-01

    , source attribution results obtained using the CMB model indicate that emissions from motor vehicle exhausts are the most important, accounting for the 64 % of the PM2.5. The vegetative detritus and biomass burning had the smallest contribution (2.2 % of the PM2.5). To our knowledge, this is the second study to explore the broad chemical characterization of fine organic aerosol in Mexico and the first for the MMA.

  12. Chemical characterization of fine organic aerosol for source apportionment at Monterrey, Mexico

    Directory of Open Access Journals (Sweden)

    Y. Mancilla

    2015-07-01

    events. Finally, source attribution results obtained using the CMB model indicate that emissions from motor vehicle exhausts are the most important, accounting for the 64 % of the PM2.5. The vegetative detritus and biomass burning had the smallest contribution (2.2 % of the PM2.5. To our knowledge, this is the second study to explore the broad chemical characterization of fine organic aerosol in Mexico and the first for the MMA.

  13. Characterization of Ground Displacement Sources from Variational Bayesian Independent Component Analysis of Space Geodetic Time Series

    Science.gov (United States)

    Gualandi, Adriano; Serpelloni, Enrico; Elina Belardinelli, Maria; Bonafede, Maurizio; Pezzo, Giuseppe; Tolomei, Cristiano

    2015-04-01

    A critical point in the analysis of ground displacement time series, as those measured by modern space geodetic techniques (primarly continuous GPS/GNSS and InSAR) is the development of data driven methods that allow to discern and characterize the different sources that generate the observed displacements. A widely used multivariate statistical technique is the Principal Component Analysis (PCA), which allows to reduce the dimensionality of the data space maintaining most of the variance of the dataset explained. It reproduces the original data using a limited number of Principal Components, but it also shows some deficiencies, since PCA does not perform well in finding the solution to the so-called Blind Source Separation (BSS) problem. The recovering and separation of the different sources that generate the observed ground deformation is a fundamental task in order to provide a physical meaning to the possible different sources. PCA fails in the BSS problem since it looks for a new Euclidean space where the projected data are uncorrelated. Usually, the uncorrelation condition is not strong enough and it has been proven that the BSS problem can be tackled imposing on the components to be independent. The Independent Component Analysis (ICA) is, in fact, another popular technique adopted to approach this problem, and it can be used in all those fields where PCA is also applied. An ICA approach enables us to explain the displacement time series imposing a fewer number of constraints on the model, and to reveal anomalies in the data such as transient deformation signals. However, the independence condition is not easy to impose, and it is often necessary to introduce some approximations. To work around this problem, we use a variational bayesian ICA (vbICA) method, which models the probability density function (pdf) of each source signal using a mix of Gaussian distributions. This technique allows for more flexibility in the description of the pdf of the sources

  14. Chemical characterization of atmospheric particles and source apportionment in the vicinity of a steelmaking industry

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, S.M., E-mail: smarta@ctn.ist.utl.pt [Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 139.7 km, 2695-066 Bobadela LRS (Portugal); Lage, J. [Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 139.7 km, 2695-066 Bobadela LRS (Portugal); Fernández, B. [Global R& D, ArcelorMittal, Avilés (Spain); Garcia, S. [Instituto de Soldadura e Qualidade, Av. Prof. Dr. Cavaco Silva, 33, 2740-120 Porto Salvo (Portugal); Reis, M.A.; Chaves, P.C. [Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 139.7 km, 2695-066 Bobadela LRS (Portugal)

    2015-07-15

    The objective of this work was to provide a chemical characterization of atmospheric particles collected in the vicinity of a steelmaking industry and to identify the sources that affect PM{sub 10} levels. A total of 94 PM samples were collected in two sampling campaigns that occurred in February and June/July of 2011. PM{sub 2.5} and PM{sub 2.5–10} were analyzed for a total of 22 elements by Instrumental Neutron Activation Analysis and Particle Induced X-ray Emission. The concentrations of water soluble ions in PM{sub 10} were measured by Ion Chromatography and Indophenol-Blue Spectrophotometry. Positive Matrix Factorization receptor model was used to identify sources of particulate matter and to determine their mass contribution to PM{sub 10}. Seven main groups of sources were identified: marine aerosol identified by Na and Cl (22%), steelmaking and sinter plant represented by As, Cr, Cu, Fe, Ni, Mn, Pb, Sb and Zn (11%), sinter plant stack identified by NH{sub 4}{sup +}, K and Pb (12%), an unidentified Br source (1.8%), secondary aerosol from coke making and blast furnace (19%), fugitive emissions from the handling of raw material, sinter plant and vehicles dust resuspension identified by Al, Ca, La, Si, Ti and V (14%) and sinter plant and blast furnace associated essentially with Fe and Mn (21%). - Highlights: • Emissions from steelworks are very complex. • The larger steelworks contribution to PM{sub 10} was from blast furnace and sinter plant. • Sinter plant stack emissions contributed for 12% of the PM{sub 10} mass. • Secondary aerosol from coke making and blast furnace contributed for 19% of the PM{sub 10}. • Fugitive dust emissions highly contribute to PM{sub 10} mass.

  15. Pseudo-dynamic source characterization accounting for rough-fault effects

    Science.gov (United States)

    Galis, Martin; Thingbaijam, Kiran K. S.; Mai, P. Martin

    2016-04-01

    Broadband ground-motion simulations, ideally for frequencies up to ~10Hz or higher, are important for earthquake engineering; for example, seismic hazard analysis for critical facilities. An issue with such simulations is realistic generation of radiated wave-field in the desired frequency range. Numerical simulations of dynamic ruptures propagating on rough faults suggest that fault roughness is necessary for realistic high-frequency radiation. However, simulations of dynamic ruptures are too expensive for routine applications. Therefore, simplified synthetic kinematic models are often used. They are usually based on rigorous statistical analysis of rupture models inferred by inversions of seismic and/or geodetic data. However, due to limited resolution of the inversions, these models are valid only for low-frequency range. In addition to the slip, parameters such as rupture-onset time, rise time and source time functions are needed for complete spatiotemporal characterization of the earthquake rupture. But these parameters are poorly resolved in the source inversions. To obtain a physically consistent quantification of these parameters, we simulate and analyze spontaneous dynamic ruptures on rough faults. First, by analyzing the impact of fault roughness on the rupture and seismic radiation, we develop equivalent planar-fault kinematic analogues of the dynamic ruptures. Next, we investigate the spatial interdependencies between the source parameters to allow consistent modeling that emulates the observed behavior of dynamic ruptures capturing the rough-fault effects. Based on these analyses, we formulate a framework for pseudo-dynamic source model, physically consistent with the dynamic ruptures on rough faults.

  16. Novel techniques for characterization of hydrocarbon emission sources in the Barnett Shale

    Science.gov (United States)

    Nathan, Brian Joseph

    Changes in ambient atmospheric hydrocarbon concentrations can have both short-term and long-term effects on the atmosphere and on human health. Thus, accurate characterization of emissions sources is critically important. The recent boom in shale gas production has led to an increase in hydrocarbon emissions from associated processes, though the exact extent is uncertain. As an original quantification technique, a model airplane equipped with a specially-designed, open-path methane sensor was flown multiple times over a natural gas compressor station in the Barnett Shale in October 2013. A linear optimization was introduced to a standard Gaussian plume model in an effort to determine the most probable emission rate coming from the station. This is shown to be a suitable approach given an ideal source with a single, central plume. Separately, an analysis was performed to characterize the nonmethane hydrocarbons in the Barnett during the same period. Starting with ambient hourly concentration measurements of forty-six hydrocarbon species, Lagrangian air parcel trajectories were implemented in a meteorological model to extend the resolution of these measurements and achieve domain-fillings of the region for the period of interest. A self-organizing map (a type of unsupervised classification) was then utilized to reduce the dimensionality of the total multivariate set of grids into characteristic one-dimensional signatures. By also introducing a self-organizing map classification of the contemporary wind measurements, the spatial hydrocarbon characterizations are analyzed for periods with similar wind conditions. The accuracy of the classification is verified through assessment of observed spatial mixing ratio enhancements of key species, through site-comparisons with a related long-term study, and through a random forest analysis (an ensemble learning method of supervised classification) to determine the most important species for defining key classes. The hydrocarbon

  17. Development and characterization of a tunable ultrafast X-ray source via inverse-Compton-scattering

    International Nuclear Information System (INIS)

    Ultrashort, nearly monochromatic hard X-ray pulses enrich the understanding of the dynamics and function of matter, e.g., the motion of atomic structures associated with ultrafast phase transitions, structural dynamics and (bio)chemical reactions. Inverse Compton backscattering of intense laser pulses from relativistic electrons not only allows for the generation of bright X-ray pulses which can be used in a pump-probe experiment, but also for the investigation of the electron beam dynamics at the interaction point. The focus of this PhD work lies on the detailed understanding of the kinematics during the interaction of the relativistic electron bunch and the laser pulse in order to quantify the influence of various experiment parameters on the emitted X-ray radiation. The experiment was conducted at the ELBE center for high power radiation sources using the ELBE superconducting linear accelerator and the DRACO Ti:sapphire laser system. The combination of both these state-of-the-art apparatuses guaranteed the control and stability of the interacting beam parameters throughout the measurement. The emitted X-ray spectra were detected with a pixelated detector of 1024 by 256 elements (each 26μm by 26μm) to achieve an unprecedented spatial and energy resolution for a full characterization of the emitted spectrum to reveal parameter influences and correlations of both interacting beams. In this work the influence of the electron beam energy, electron beam emittance, the laser bandwidth and the energy-anglecorrelation on the spectra of the backscattered X-rays is quantified. A rigorous statistical analysis comparing experimental data to ab-initio 3D simulations enabled, e.g., the extraction of the angular distribution of electrons with 1.5% accuracy and, in total, provides predictive capability for the future high brightness hard X-ray source PHOENIX (Photon electron collider for Narrow bandwidth Intense X-rays) and potential all optical gamma-ray sources. The results

  18. Central and Eastern United States (CEUS) Seismic Source Characterization (SSC) for Nuclear Facilities Project

    Energy Technology Data Exchange (ETDEWEB)

    Kevin J. Coppersmith; Lawrence A. Salomone; Chris W. Fuller; Laura L. Glaser; Kathryn L. Hanson; Ross D. Hartleb; William R. Lettis; Scott C. Lindvall; Stephen M. McDuffie; Robin K. McGuire; Gerry L. Stirewalt; Gabriel R. Toro; Robert R. Youngs; David L. Slayter; Serkan B. Bozkurt; Randolph J. Cumbest; Valentina Montaldo Falero; Roseanne C. Perman' Allison M. Shumway; Frank H. Syms; Martitia (Tish) P. Tuttle

    2012-01-31

    This report describes a new seismic source characterization (SSC) model for the Central and Eastern United States (CEUS). It will replace the Seismic Hazard Methodology for the Central and Eastern United States, EPRI Report NP-4726 (July 1986) and the Seismic Hazard Characterization of 69 Nuclear Plant Sites East of the Rocky Mountains, Lawrence Livermore National Laboratory Model, (Bernreuter et al., 1989). The objective of the CEUS SSC Project is to develop a new seismic source model for the CEUS using a Senior Seismic Hazard Analysis Committee (SSHAC) Level 3 assessment process. The goal of the SSHAC process is to represent the center, body, and range of technically defensible interpretations of the available data, models, and methods. Input to a probabilistic seismic hazard analysis (PSHA) consists of both seismic source characterization and ground motion characterization. These two components are used to calculate probabilistic hazard results (or seismic hazard curves) at a particular site. This report provides a new seismic source model. Results and Findings The product of this report is a regional CEUS SSC model. This model includes consideration of an updated database, full assessment and incorporation of uncertainties, and the range of diverse technical interpretations from the larger technical community. The SSC model will be widely applicable to the entire CEUS, so this project uses a ground motion model that includes generic variations to allow for a range of representative site conditions (deep soil, shallow soil, hard rock). Hazard and sensitivity calculations were conducted at seven test sites representative of different CEUS hazard environments. Challenges and Objectives The regional CEUS SSC model will be of value to readers who are involved in PSHA work, and who wish to use an updated SSC model. This model is based on a comprehensive and traceable process, in accordance with SSHAC guidelines in NUREG/CR-6372, Recommendations for Probabilistic

  19. Simple circular odor chart for characterization of trace amounts of odorants discharged from thirteen odor sources

    Energy Technology Data Exchange (ETDEWEB)

    Hoshika, Y.; Nihei, Y.; Muto, G.

    1981-04-01

    A simple circular odor chart is proposed for the explanation of the relationship between sensory responses (to odor quality and intensity) to odors and chemical analysis data of the odorants responsible for each odor discharged from thirteen odor sources. The odorants were classified into eight odorant groups and were analyzed by a systematic gas chromatographic (GC) technique. The characterization of the trace amounts of the odorants was carried out by using the values of a new proposed unit (pOU) based on the ratio of detected concentration to recognition threshold value. The calculated pOU values of the eight groups were plotted in circular charts. It was found that the shape and size of each circular odor chart represent the quality and the intensity of each odor.

  20. Flux growth and characterization of cuprorivaite: the influence of temperature, flux, and silica source

    Science.gov (United States)

    Bloise, A.; Abd El Salam, S.; De Luca, R.; Crisci, G. M.; Miriello, D.

    2016-07-01

    Single crystals of cuprorivaite (CaCuSi4O10), one of the oldest synthetic color pigments of Egyptian history, have been synthesized by slow-cooling flux method. Several runs were carried out at temperatures between 800 and 960 °C and with reaction times ranging from 10 to 72 h. The starting materials and run products were characterized by binocular microscope, X-ray powder diffraction, scanning electron microscopy with annexed energy-dispersive spectrometry, and μ-Raman spectroscopy. The effects of growth parameters (temperature, flux, silica source) on yield and size of crystals were studied. The growth of cuprorivaite depends greatly on the starting materials: they are observed as run products only using natron as flux. Furthermore, colorimetric analysis performed on the synthesizing pigment was compared with the archeological samples present in the literature in order to value similarities and differences.

  1. Characterization of source rocks and groundwater radioactivity at the Chihuahua valley

    Energy Technology Data Exchange (ETDEWEB)

    Renteria V, M.; Montero C, M.E.; Reyes C, M.; Herrera P, E.F.; Valenzuela H, M. [Centro de lnvestigacion en Materiales Avanzados, Miguel de Cervantes 120, 31109 Chihuahua, (Mexico); Rodriguez P, A. [World Wildlife Fund (WWF), Chihuahuan Desert Program, Coronado 1005, 31000 Chihuahua (Mexico); Manjon C, G.; Garcia T, R. [Universidad de Sevilla, Departamento de Fisica Aplicada 11, ETS Arquitectura, Av. Reina Mercedes 2, 41012 Sevilla, (Spain); Crespo, T. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Av. Complutense 22, 28040 Madrid, (Spain)]. e-mail: elena.montero@cimav.edu.mx

    2007-07-01

    As part of a scientific research project about alpha radioactivity in groundwater for human consumption at the Chihuahua City, the characterization of rock sources of radioactivity around de Chihuahua valley was developed. The radioactivity of groundwater and sediments was determined, too. The radioactivity of uranium- and thorium- series isotopes contained in rocks was obtained by high resolution gamma-ray spectroscopy. Some representative values are 50 Bq/kg for the mean value of Bi-214 activity, and 121.5 Bq/kg for the highest value at West of the city. The activity of sediments, extracted during wells perforation, was determined using a Nal(TI) detector. A non-reported before uranium ore was localized at the San Marcos range formation. Its outcrops are inside the Chihuahua-Sacramento valley basin and its activity characterization was performed. Unusually high specific uranium activities, determined by alpha spectrometry, were obtained in water, plants, sediments and fish extracted at locations close to outcrops of uranium minerals. The activity of water of the San Marcos dam reached 7.7 Bq/L. The activity of fish, trapped at San Marcos dam, is 0.99 Bq/kg. Conclusions about the contamination of groundwater at North of Chihuahua City were obtained. (Author)

  2. Characterization of a FEL lamp type source towards a blue light irradiance intercomparison in medical field

    Science.gov (United States)

    Ferreira, A. F. G., Jr.

    2011-01-01

    This work presents the characterization of modified FEL 1000W lamp housing to be used as a transference standard in the blue light irradiance intercomparison. It aims to support the metrological issues of medical equipment manufactures concerning the phototherapy treatment stated on the standard NBR/IEC 60601-2-50. The light source characterization consists of lamp seasoning, lamp short-term drift and lamp irradiance relative spatial distribution at the plane of measurement. The lamp seasoning is performed by a software developed in LabView® which measures the lamp voltage, current and irradiance at each 5 minutes during 25 hours of seasoning. The lamp short-term drift is evaluated by measuring the lamp irradiance during a sequence of 2 hours of lamp using. The lamp irradiance relative spatial distribution is verified using a radiometer head with a reduced aperture attached to an YZ positing system at each 2 mm in an interval of 24 mm. The lamp presented variation of about 0.1%/h during seasoning. Short-term drift for the lamp after a warm-up of 20 minutes was less than 0.9% for series of 4 lamp switching cycles. Lamp irradiance relative spatial distribution showed a variation of ±1.25% for a circular diameter of 20 mm. The overall uncertainty for lamp irradiance was 3.65%.

  3. Characterization of a FEL lamp type source towards a blue light irradiance intercomparison in medical field

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, A F G Jr, E-mail: agentil@ipt.br [Laboratorio de Equipamentos Elotricos e Opticos, Instituto de Pesquisas Tecnologicas do Estado de Sao Paulo, Avenida Professor Almeida Prado, 532, 05508-901 (Brazil)

    2011-01-01

    This work presents the characterization of modified FEL 1000W lamp housing to be used as a transference standard in the blue light irradiance intercomparison. It aims to support the metrological issues of medical equipment manufactures concerning the phototherapy treatment stated on the standard NBR/IEC 60601-2-50. The light source characterization consists of lamp seasoning, lamp short-term drift and lamp irradiance relative spatial distribution at the plane of measurement. The lamp seasoning is performed by a software developed in LabView (registered) which measures the lamp voltage, current and irradiance at each 5 minutes during 25 hours of seasoning. The lamp short-term drift is evaluated by measuring the lamp irradiance during a sequence of 2 hours of lamp using. The lamp irradiance relative spatial distribution is verified using a radiometer head with a reduced aperture attached to an YZ positing system at each 2 mm in an interval of 24 mm. The lamp presented variation of about 0.1%/h during seasoning. Short-term drift for the lamp after a warm-up of 20 minutes was less than 0.9% for series of 4 lamp switching cycles. Lamp irradiance relative spatial distribution showed a variation of {+-}1.25% for a circular diameter of 20 mm. The overall uncertainty for lamp irradiance was 3.65%.

  4. Characterization of source rocks and groundwater radioactivity at the Chihuahua valley

    International Nuclear Information System (INIS)

    As part of a scientific research project about alpha radioactivity in groundwater for human consumption at the Chihuahua City, the characterization of rock sources of radioactivity around de Chihuahua valley was developed. The radioactivity of groundwater and sediments was determined, too. The radioactivity of uranium- and thorium- series isotopes contained in rocks was obtained by high resolution gamma-ray spectroscopy. Some representative values are 50 Bq/kg for the mean value of Bi-214 activity, and 121.5 Bq/kg for the highest value at West of the city. The activity of sediments, extracted during wells perforation, was determined using a Nal(TI) detector. A non-reported before uranium ore was localized at the San Marcos range formation. Its outcrops are inside the Chihuahua-Sacramento valley basin and its activity characterization was performed. Unusually high specific uranium activities, determined by alpha spectrometry, were obtained in water, plants, sediments and fish extracted at locations close to outcrops of uranium minerals. The activity of water of the San Marcos dam reached 7.7 Bq/L. The activity of fish, trapped at San Marcos dam, is 0.99 Bq/kg. Conclusions about the contamination of groundwater at North of Chihuahua City were obtained. (Author)

  5. Cretaceous source rock characterization of the Atlantic Continental margin of Morocco

    Energy Technology Data Exchange (ETDEWEB)

    Jabour, H. (ONAREP, Rabat (Morocco))

    1993-02-01

    Characterization of the petroleum potential for the Atlantic margin of Morocco has been based primarily on limited, antiently acquired organic geochemical data. These indicate the area of drilling behind the paleoshelf edge to be only fair in organic carbon and C15+ extract values with predominantly terrestrial kerogen types. Recently acquired geochemical data obtained from relatively recent drilling both behind and beyond the paleoshelf edge indicate 4 depositional facies containing hydrogen rich amorphous kerogen assemblages. These are: (1) Lower to Mid Jurassic inner shelf facies probably deposited in algal rich lagoon-like, (2) Lower Cretaceous non marine coaly facies probably deposited in algal rich swamplike environments, (3) Middle Cretaceous facies characterized by restrited anoxic environment with sediments rich in marine kerogen types deposited under sluggish wather circulation, (4) Upper Cretaceous to Tertiary outer-shelf to Upper slope facies probably deposited under algal-rich upwelling systems. Of these, the Cretaceous facies is the most widespread and represents the best source rock potential characteristics. Correlation of these facies to recently acquired good quality seismic packages allows for extrapolation of probable organic facies distribution throughout the continental margin. This should enhance the hydrocarbon potential of the Mesozoic and Cenozoic sediments both landward and seaward of the paleoshelf edge and thus permits refinement of strategies for hydrocarbon exploration in the area.

  6. Accelerated multi-source remedial approach using field sample evaluation for site characterization and closure

    International Nuclear Information System (INIS)

    An active 128-acre industrial site, which has been operating since 1868, located in southern New Jersey was effectively remediated in three months using an accelerated multi-source remedial approach which uses field sample evaluation for site characterization and closure. Through extensive multi-remedial investigations consisting of the collection and laboratory analysis of 849 soil samples, and the installation and subsequent sampling of 60 ground water monitoring wells, 73 areas of environmental concern were identified and subsequently designated for remedial action. An aggressive remedial approach was conducted which consisted of soil excavation, including post-excavation sampling to ensure that compliance with applicable New Jersey soil cleanup criteria was achieved. Waste loading, transportation and proper disposal at a designated facility, and the use of a full service mobile laboratory for post-excavation soil sample characterization was achieved within the project time-frame. The mobile laboratory was an integral component of the remedial approach. It provided volatile organic, base-neutral, total petroleum hydrocarbon, and priority pollutant metals analyses on post-excavation soil samples using approved laboratory methods. Use of the mobile laboratory provided multiparameter sample results for field evaluation within 24 hours of collection, which expedited remediation activities allowing areas to be evaluated and backfilled immediately, as appropriate. This approach allowed rapid restoration of the remediation areas, thereby greatly reducing disruptions in facility operations. Quality Assurance/Quality Control methods consisted of the use of a fixed base laboratory for confirmation sample analysis of 10% of the samples collected

  7. Characterization of swine stress gene by DNA testing using plucked hair as a source of DNA

    Directory of Open Access Journals (Sweden)

    Bastos Reginaldo Gaspar

    2000-01-01

    Full Text Available The swine stress gene (hal in recessive homozygotes (nn leads to porcine stress syndrome (PSS, and is associated with pale, soft, exudative pork (PSE. In heterozygosis (Nn it is linked to poor carcass quality. A total of 179 pigs (86 Large White, 69 Landrace, 12 Duroc and 12 Pietrain were characterized as normal homozygotes (NN, heterozygotes or recessive homozygotes following amplification of a target region of the hal gene using the polymerase chain reaction (PCR, followed by a restriction endonuclease assay. Plucked hair was used as a source of genomic DNA. The resulting PCR was digested with the restriction enzyme CfoI, followed by agarose gel electrophoresis. Of 179 animals tested, 70% were NN, 28% were Nn, and 2% were nn. The frequency of heterozygotes was higher (P < 0.05 in Landrace (0.43 for Nn than in Large White pigs (0.09 for Nn. Nine of the 12 Pietrain animals were Nn and three were nn, suggesting a high frequency for the n allele in this breed. These results may be related to the incidence of PSS and PSE in these two breeds, both of which are widely used in breeding programs. The utilization of plucked hair as the source of genomic DNA was a non-invasive and quick method to screen farm animals.

  8. Isolation and molecular characterization of free-living amoebae from different water sources in Italy.

    Science.gov (United States)

    Montalbano Di Filippo, Margherita; Santoro, Maristella; Lovreglio, Piero; Monno, Rosa; Capolongo, Carmen; Calia, Carla; Fumarola, Luciana; D'Alfonso, Rossella; Berrilli, Federica; Di Cave, David

    2015-03-24

    Free-living amoebae (FLA) are protozoa ubiquitous in Nature, isolated from a variety of environments worldwide. In addition to their natural distribution, some species have been found to be pathogenic to humans. In the present study a survey was conducted in order to evaluate the presence and to characterize at molecular level the isolates of amoebic organisms collected from different water sources in Italy. A total of 160 water samples were analyzed by culture and microscopic examination. FLA were found in 46 (28.7%) of the investigated water samples. Groundwater, well waters, and ornamental fountain waters were the sources with higher prevalence rates (85.7%, 50.0%, and 45.9%, respectively). Identification of FLA species/genotypes, based on the 18S rDNA regions, allowed to identify 18 (39.1%) Acanthamoeba isolates (genotypes T4 and T15) and 21 (45.6%) Vermamoeba vermiformis isolates. Other FLA species, including Vahlkampfia sp. and Naegleria spp., previously reported in Italy, were not recovered. The occurrence of potentially pathogenic free-living amoebae in habitats related to human population, as reported in the present study, supports the relevance of FLA as a potential health threat to humans.

  9. Isolation and Molecular Characterization of Free-Living Amoebae from Different Water Sources in Italy

    Directory of Open Access Journals (Sweden)

    Margherita Montalbano Di Filippo

    2015-03-01

    Full Text Available Free-living amoebae (FLA are protozoa ubiquitous in Nature, isolated from a variety of environments worldwide. In addition to their natural distribution, some species have been found to be pathogenic to humans. In the present study a survey was conducted in order to evaluate the presence and to characterize at molecular level the isolates of amoebic organisms collected from different water sources in Italy. A total of 160 water samples were analyzed by culture and microscopic examination. FLA were found in 46 (28.7% of the investigated water samples. Groundwater, well waters, and ornamental fountain waters were the sources with higher prevalence rates (85.7%, 50.0%, and 45.9%, respectively. Identification of FLA species/genotypes, based on the 18S rDNA regions, allowed to identify 18 (39.1% Acanthamoeba isolates (genotypes T4 and T15 and 21 (45.6% Vermamoeba vermiformis isolates. Other FLA species, including Vahlkampfia sp. and Naegleria spp., previously reported in Italy, were not recovered. The occurrence of potentially pathogenic free-living amoebae in habitats related to human population, as reported in the present study, supports the relevance of FLA as a potential health threat to humans.

  10. Design of an inexpensive integrating sphere student laboratory setup for the optical characterization of light sources

    Science.gov (United States)

    Leloup, Frédéric B.; Leyre, Sven; Bauwens, Eva; Van den Abeele, Toon; Hanselaer, Peter

    2016-01-01

    In this paper, the design of an inexpensive integrating sphere setup is presented, enabling students to perform optical characterization of light sources with reasonable accuracy, in a student laboratory context. Instead of using an expensive sphere with magnesium oxide or barium sulfate coating, a cheap polystyrene sphere is employed. In combination with a low-cost USB spectroradiometer, the system enables the direct measurement of the spectral radiant power of a light source. In addition to the radiant power, the luminous flux, luminous efficacy, and distinctive colorimetric quantities (colour coordinates, colour temperature, and colour rendering index) can be determined. Besides a description of the equipment used, the experimental measurement procedure and some typical measurement results are presented. A comparison between the data and the results obtained with scientific metrology instrumentation indicates reasonable accuracy. As a result, it can be concluded that the purpose of the presented experiments, being that students become acquainted with applications of radiometry and photometry, and with data collection and data analysis as in a professional context, is fully achieved with the described test setup.

  11. Chemical and isotopic methods for characterization of pollutant sources in rain water

    International Nuclear Information System (INIS)

    The acid rain formation is related with industrial pollution. An isotopic and chemical study of the spatial and temporary distribution of the acidity in the rain gives information about the acidity source. The predominant species in the acid rain are nitrates and sulfates. For the rain monitoring is required the determination of the anion species such as HCO3, Cl, SO4, NO3 and p H. So it was analyzed the cations Na+ , K+ , Ca2+ and Mg2+ to determine the quality analysis. All of them species can be determined with enough accuracy, except HCO3 by modern equipment such as, liquid chromatograph, atomic absorption, etc. The HCO3 concentration is determined by traditional methods like acid-base titration. This work presents the fundamental concepts of the titration method for samples with low alkalinity (carbonic species), for rain water. There is presented a general overview over the isotopic methods for the characterization of the origin of pollutant sources in the rain. (Author)

  12. Analysis of the Degradation of MOSFETs in Switching Mode Power Supply by Characterizing Source Oscillator Signals

    Directory of Open Access Journals (Sweden)

    Xueyan Zheng

    2013-01-01

    Full Text Available Switching Mode Power Supply (SMPS has been widely applied in aeronautics, nuclear power, high-speed railways, and other areas related to national strategy and security. The degradation of MOSFET occupies a dominant position in the key factors affecting the reliability of SMPS. MOSFETs are used as low-voltage switches to regulate the DC voltage in SMPS. The studies have shown that die-attach degradation leads to an increase in on-state resistance due to its dependence on junction temperature. On-state resistance is the key indicator of the health of MOSFETs. In this paper, an online real-time method is presented for predicting the degradation of MOSFETs. First, the relationship between an oscillator signal of source and on-state resistance is introduced. Because oscillator signals change when they age, a feature is proposed to capture these changes and use them as indicators of the state of health of MOSFETs. A platform for testing characterizations is then established to monitor oscillator signals of source. Changes in oscillator signal measurement were observed with aged on-state resistance as a result of die-attach degradation. The experimental results demonstrate that the method is efficient. This study will enable a method to predict the failure of MOSFETs to be developed.

  13. sources

    Directory of Open Access Journals (Sweden)

    Shu-Yin Chiang

    2002-01-01

    Full Text Available In this paper, we study the simplified models of the ATM (Asynchronous Transfer Mode multiplexer network with Bernoulli random traffic sources. Based on the model, the performance measures are analyzed by the different output service schemes.

  14. Characterization of the DD-neutron source for the 80 degrees beam line of the fusion neutronics source (FNS)

    International Nuclear Information System (INIS)

    The specification of the d-D neutron source with a titanium deuteride target of the FNS facility was investigated in order to utilize the d-D neutron source for fusion neutronics researches. The characteristics of neutron produced by the d-D reaction were described based on the reaction kinematics, and the target assembly of the accelerator was modeled for the MCNP calculation in detail. In order to validate this calculation, the angular distribution of the neutron was measured with the activation foil method. The measured reaction rates were well predicted by the MCNP calculation, and the validity of the present calculation was confirmed. A MCNP source term for analyses calculations of experiments with DD neutrons was prepared from the results of the above calculation. (author)

  15. Sources

    OpenAIRE

    2015-01-01

    Sources Fondation Pablo Iglesias. Alcala de Henares. Sections : Archives privées de Manuel ArijaArchives extérieuresArchives FNJS de EspañaPrensa Archives Générales de l’Administration. Alcala de Henares. Sections : Opposition au franquismeSig. 653 Sig TOP 82/68.103-68.602.Índice de las cartas colectivas, Relaciones, Cartas al Ministro de Información de Marzo de 1965. c.662. Sources cinématographiques Filmothèque Nationale d’Espagne.NO.DO. N° 1157C. 08/03/1965.aguirre Javier, Blanco vertical....

  16. Source characterization of major emission sources in the Imperial and Mexicali Valleys along the US/Mexico border

    Energy Technology Data Exchange (ETDEWEB)

    Watson, J.G.; Chow, J.C. [Desert Research Institute, 2215 Raggio Pkwy., 89512 Reno, NV (United States)

    2001-08-10

    Chemical profiles for particle emissions are needed for source apportionment studies using the chemical mass balance (CMB) receptor model. Source measurements of geological sources, motor vehicle exhaust, vegetative burning (e.g. asparagus, field burning, charbroil cooking), and industrial sources (e.g. oil-fueled glass plant, manure-fueled power plants) were acquired as part of the Imperial/Mexicali Valley Cross Border PM{sub 10} Transport Study in 1992. Six different source sampling techniques (i.e. hot- and diluted-exhaust sampling, ground-based source sampling, particle sweeping/grab sampling, vacuum sampling, and laboratory resuspension sampling) were applied to acquire filter samples of PM{sub 2.5} and PM{sub 10} (particulate matter with aerodynamic diameters <2.5 and 10 {mu}m, respectively). Filter samples were analyzed for mass by gravimetry, elements (Na to U) by X-ray fluorescence, anions (Cl{sup -}, NO{sub 3}{sup -}, SO{sub 4}{sup =}) by ion chromatography, ammonium (NH{sub 4}{sup +}) by automated colorimetry, soluble sodium (Na{sup +}) and potassium (K{sup +}) by atomic absorption spectrophotometry, and organic and elemental carbon (OC, EC) by thermal/optical reflectance. Concentration data were acquired for a total of 50 chemical species. Elevated abundances of crustal components (Al, Si, K, Ca, Fe) from geological material, carbon (OC, EC) and trace elements (Br, Pb) from vehicle exhausts, carbon (OC, EC) and ions (K{sup +}, Cl{sup -}) from vegetative burning, ions (SO{sub 4}{sup =}, NH{sub 4}{sup +}, Na{sup +}, K{sup +}, Cl{sup -}) and elements (Cl, Se) from a manure-fueled power plants, and sulfur and trace elements (Na{sup +}, Pb, Se, Ni, V) from an oil-fueled glass plant were found in the resulting source profiles. Abundances of crustal species (e.g. Al, Si, Ca) in the Imperial/Mexicali Valley geological profiles are more than twice those found in central and southern California. Abundances of lead in motor vehicle exhausts indicate different

  17. A measurement-based X-ray source model characterization for CT dosimetry computations.

    Science.gov (United States)

    Sommerville, Mitchell; Poirier, Yannick; Tambasco, Mauro

    2015-11-08

    The purpose of this study was to show that the nominal peak tube voltage potential (kVp) and measured half-value layer (HVL) can be used to generate energy spectra and fluence profiles for characterizing a computed tomography (CT) X-ray source, and to validate the source model and an in-house kV X-ray dose computation algorithm (kVDoseCalc) for computing machine- and patient-specific CT dose. Spatial variation of the X-ray source spectra of a Philips Brilliance and a GE Optima Big Bore CT scanner were found by measuring the HVL along the direction of the internal bow-tie filter axes. Third-party software, Spektr, and the nominal kVp settings were used to generate the energy spectra. Beam fluence was calculated by dividing the integral product of the spectra and the in-air NIST mass-energy attenuation coefficients by in-air dose measurements along the filter axis. The authors found the optimal number of photons to seed in kVDoseCalc to achieve dose convergence. The Philips Brilliance beams were modeled for 90, 120, and 140 kVp tube settings. The GE Optima beams were modeled for 80, 100, 120, and 140 kVp tube settings. Relative doses measured using a Capintec Farmer-type ionization chamber (0.65 cc) placed in a cylindrical polymethyl methacrylate (PMMA) phantom and irradiated by the Philips Brilliance, were compared to those computed with kVDoseCalc. Relative doses in an anthropomorphic thorax phantom (E2E SBRT Phantom) irradiated by the GE Optima were measured using a (0.015 cc) PTW Freiburg ionization chamber and compared to computations from kVDoseCalc. The number of photons required to reduce the average statistical uncertainty in dose to < 0.3% was 2 × 105. The average percent difference between calculation and measurement over all 12 PMMA phantom positions was found to be 1.44%, 1.47%, and 1.41% for 90, 120, and 140 kVp, respectively. The maximum percent difference between calculation and measurement for all energies, measurement positions, and phantoms was

  18. A measurement-based X-ray source model characterization for CT dosimetry computations.

    Science.gov (United States)

    Sommerville, Mitchell; Poirier, Yannick; Tambasco, Mauro

    2015-01-01

    The purpose of this study was to show that the nominal peak tube voltage potential (kVp) and measured half-value layer (HVL) can be used to generate energy spectra and fluence profiles for characterizing a computed tomography (CT) X-ray source, and to validate the source model and an in-house kV X-ray dose computation algorithm (kVDoseCalc) for computing machine- and patient-specific CT dose. Spatial variation of the X-ray source spectra of a Philips Brilliance and a GE Optima Big Bore CT scanner were found by measuring the HVL along the direction of the internal bow-tie filter axes. Third-party software, Spektr, and the nominal kVp settings were used to generate the energy spectra. Beam fluence was calculated by dividing the integral product of the spectra and the in-air NIST mass-energy attenuation coefficients by in-air dose measurements along the filter axis. The authors found the optimal number of photons to seed in kVDoseCalc to achieve dose convergence. The Philips Brilliance beams were modeled for 90, 120, and 140 kVp tube settings. The GE Optima beams were modeled for 80, 100, 120, and 140 kVp tube settings. Relative doses measured using a Capintec Farmer-type ionization chamber (0.65 cc) placed in a cylindrical polymethyl methacrylate (PMMA) phantom and irradiated by the Philips Brilliance, were compared to those computed with kVDoseCalc. Relative doses in an anthropomorphic thorax phantom (E2E SBRT Phantom) irradiated by the GE Optima were measured using a (0.015 cc) PTW Freiburg ionization chamber and compared to computations from kVDoseCalc. The number of photons required to reduce the average statistical uncertainty in dose to < 0.3% was 2 × 105. The average percent difference between calculation and measurement over all 12 PMMA phantom positions was found to be 1.44%, 1.47%, and 1.41% for 90, 120, and 140 kVp, respectively. The maximum percent difference between calculation and measurement for all energies, measurement positions, and phantoms was

  19. Characterization of sources and loadings of fecal pollutants using microbial source tracking assays in urban and rural areas of the Grand River Watershed, Southwestern Ontario.

    Science.gov (United States)

    Lee, Dae-Young; Lee, Hung; Trevors, Jack T; Weir, Susan C; Thomas, Janis L; Habash, Marc

    2014-04-15

    Sources of fecal water pollution were assessed in the Grand River and two of its tributaries (Ontario, Canada) using total and host-specific (human and bovine) Bacteroidales genetic markers in conjunction with reference information, such as land use and weather. In-stream levels of the markers and culturable Escherichia coli were also monitored during multiple rain events to gain information on fecal loadings to catchment from diffuse sources. Elevated human-specific marker levels were accurately identified in river water impacted by a municipal wastewater treatment plant (WWTP) effluent and at a downstream site in the Grand River. In contrast, the bovine-specific marker showed high levels of cattle fecal pollution in two tributaries, both of which are characterized as intensely farmed areas. The bovine-specific Bacteroidales marker increased with rainfall in the agricultural tributaries, indicating enhanced loading of cattle-derived fecal pollutants to river from non-point sources following rain events. However, rain-triggered fecal loading was not substantiated in urban settings, indicating continuous inputs of human-originated fecal pollutants from point sources, such as WWTP effluent. This study demonstrated that the Bacteroidales source tracking assays, in combination with land use information and hydrological data, may provide additional insight into the spatial and temporal distribution of source-specific fecal contamination in streams impacted by varying land uses. Using the approach described in this study may help to characterize impacted water sources and to design targeted land use management plans in other watersheds in the future. PMID:24509346

  20. Characterization and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in Sediments from the Bohai Sea, China

    Science.gov (United States)

    Liu, Jihua; Hu, Ningjing; Shi, Xuefa

    2015-04-01

    Characterization and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in Sediments from the Bohai Sea, China Liu Jihua, Hu Ningjing, Shi Xuefa First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China Polycyclic aromatic hydrocarbons (PAHs) are a class of ubiquitous organic contaminants in the environment. Indeed, 16 PAH compounds have been listed as priority pollutants by the United States Environmental Protection Agency and the European Union because of their potential toxicity to humans and ecosystems. As POPs are released or escape into the environment, their global accumulation in marine sediments generates a complex balance between inputs and outputs. Furthermore, PAHs in coastal sediments can serve as effective tracers of materials transport from land-to-sea (Fang et al., 2009). Hence, investigations of PAHs in sediments can provide useful information for further understanding of environmental processes and material transport. In this study, sixteen polycyclic aromatic hydrocarbons (PAHs) were extracted from a total of 112 surface sediment samples collected across the entire territory of the Bohai Sea. The detectable concentrations of PAHs ranged from 97.2 to 300.7 ng/g across all samples, indicating low contamination levels of PAHs compared with reported values for other coastal sediments in China and developed countries. The highest concentrations were found within three belts in the vicinity of Luan River Estuary-Qinhuangdao Harbor, the Cao River Estuary-Bohai Sea Center, and north of the Yellow River Estuary. The distribution patterns of PAHs and source identification implied that PAH contamination in the Bohai Sea mainly originates from offshore oil exploration, sewage discharge from rivers and shipping activities. Further Principal components analysis (PCA)/multivariate linear regression (MLR) analysis suggested that the contributions of spilled oil products (petrogenic), coal combustion and traffic

  1. Synthesis and characterization of single-source molecular precursors for the preparation of metal chalcogenides

    Indian Academy of Sciences (India)

    Vimal K Jain

    2006-11-01

    Metal chalcogenides constitute an important family of functional materials. Subtle changes in shape, size and phase of these materials result in variations in physical properties (e.g. electronic and optical), which can be exploited for various technological applications. Several strategies have evolved recently for controlling shape, size and phase of these materials. This work discusses design and synthesis of single-source molecular precursors for the preparation of metal chalcogenides both in bulk and nano-size regime. Precursors for palladium chalcogenides, indium sulphides and II-VI materials are presented. Synthesis of a variety of palladium(II)/platinum(II) complexes with internally functionalised chalcogenolate ligands, selenocarboxylates; gallium and indium dithiolate complexes and zinc/cadmium/mercury complexes with N,N'-dimethylaminoalkylselenolate ligands and their characterization by NMR and X-ray crystallography are also discussed. Data on thermal behaviour of a few representative complexes, [Pd(SeCOAr)2(PR3)2], [PdCl(E∩N)(PR3)], [InMe2(S∩S)], [In(S∩S)3] and [M(E(CH2)NMe2)2] (M = Zn, Cd, Hg; = 2 or 3) are presented.

  2. Comprehensive transcriptomic and proteomic characterization of human mesenchymal stem cells reveals source specific cellular markers.

    Science.gov (United States)

    Billing, Anja M; Ben Hamidane, Hisham; Dib, Shaima S; Cotton, Richard J; Bhagwat, Aditya M; Kumar, Pankaj; Hayat, Shahina; Yousri, Noha A; Goswami, Neha; Suhre, Karsten; Rafii, Arash; Graumann, Johannes

    2016-01-01

    Mesenchymal stem cells (MSC) are multipotent cells with great potential in therapy, reflected by more than 500 MSC-based clinical trials registered with the NIH. MSC are derived from multiple tissues but require invasive harvesting and imply donor-to-donor variability. Embryonic stem cell-derived MSC (ESC-MSC) may provide an alternative, but how similar they are to ex vivo MSC is unknown. Here we performed an in depth characterization of human ESC-MSC, comparing them to human bone marrow-derived MSC (BM-MSC) as well as human embryonic stem cells (hESC) by transcriptomics (RNA-seq) and quantitative proteomics (nanoLC-MS/MS using SILAC). Data integration highlighted and validated a central role of vesicle-mediated transport and exosomes in MSC biology and also demonstrated, through enrichment analysis, their versatility and broad application potential. Particular emphasis was placed on comparing profiles between ESC-MSC and BM-MSC and assessing their equivalency. Data presented here shows that differences between ESC-MSC and BM-MSC are similar in magnitude to those reported for MSC of different origin and the former may thus represent an alternative source for therapeutic applications. Finally, we report an unprecedented coverage of MSC CD markers, as well as membrane associated proteins which may benefit immunofluorescence-based applications and contribute to a refined molecular description of MSC. PMID:26857143

  3. The synthesis conditions, characterizations and thermal degradation studies of an etherified starch from an unconventional source

    International Nuclear Information System (INIS)

    Starch isolated from an under-utilized legume plant (pigeon pea) was carboxymethylated. Influences of reaction parameters were investigated on the degree of substitution (DS) and the reaction efficiency (RE). Studies showed that optimal DS of 1.12 could be reached at reaction efficiency of 80.6 % in isopropanol-water reaction medium (40 deg. C, 3h). The scanning electron microscopy showed that after carboxymethylation, the granular appearance of the native starch was distorted. Wide-angle X-ray diffractometry revealed that crystallinity was reduced significantly after carboxymethylation. The infrared spectra revealed new bands in the carboxymethyl starch at ν =1600, 1426 and 1324 cm-1 and they were attributed to carbonyl functional groups vibration, -CH2 scissoring and OH bending vibration respectively. Broad band 13C NMR of carboxymethyl starch showed intense peak at δ 180.3 ppm and it was assigned for carbonyl carbon on the carboxymethyl substituent on the AGU (Anhydroglucose Unit). DEPT (Distortionless Enhancement by Polarization Transfer) 135 NMR showed negative signals which correspond to methylene carbons on the AGU. The differential scanning calorimetry (DSC) suggests loss of crystallinity after carboxymethylation. Thermogravimetry (TG), Derivative Thermogravimetry (DTG) and Differential Thermal Analysis (DTA) show that thermal stability improved after carboxymethylation. The study provides information on the preparation and characterization of a biomaterial from a new source which could be used alone or in the preparation of other functional polymers for diverse polymer applications. (author)

  4. Optically pumped semiconductor lasers: Conception and characterization of a single mode source for Cesium atoms manipulation

    International Nuclear Information System (INIS)

    Lasers currently used in atomic clocks or inertial sensors are suffering from a lack of power, narrow linewidth or compactness for future spatial missions. Optically pumped semiconductor lasers, which combine the approach of classical solid state lasers and the engineering of semiconductor laser, are considered here as a candidate to a metrological laser source dedicated to the manipulation of Cesium atoms in these instruments. These lasers have demonstrated high power laser emission in a circular single transverse mode, as well as single longitudinal mode emission, favoured by the semiconductor structure and the external cavity design. We study the definition and the characterization of a proper semiconductor structure for the cooling and the detection of Cesium atoms at 852 nm. A compact and robust prototype tunable on the Cesium D2 hyperfine structure is built. The laser frequency is locked to an atomic transition thanks to a saturated absorption setup. The emission spectral properties are investigated, with a particular attention to the laser frequency noise and the laser linewidth. Finally, we describe and model the thermal properties of the semiconductor structure, which enables the simulation of the laser power characteristic. The experimental parameters are optimised to obtain the maximum output power with our structure. Thanks to our analysis, we propose several ways to overcome these limitations, by reducing the structure heating. (authors)

  5. Site Characterization of the Source Physics Experiment Phase II Location Using Seismic Reflection Data

    Science.gov (United States)

    Sexton, E. A.; Snelson, C. M.; Chipman, V.; Emer, D. F.; White, R. L.; Emmitt, R.; Wright, A. A.; Drellack, S.; Huckins-Gang, H.; Mercadante, J.; Floyd, M.; McGowin, C.; Cothrun, C.; Bonal, N.

    2013-12-01

    An objective of the Source Physics Experiment (SPE) is to identify low-yield nuclear explosions from a regional distance. Low-yield nuclear explosions can often be difficult to discriminate among the clutter of natural and man-made explosive events (e.g., earthquakes and mine blasts). The SPE is broken into three phases. Phase I has provided the first of the physics-based data to test the empirical models that have been used to discriminate nuclear events. The Phase I series of tests were placed within a highly fractured granite body. The evolution of the project has led to development of Phase II, to be placed within the opposite end member of geology, an alluvium environment, thereby increasing the database of waveforms to build upon in the discrimination models. Both the granite and alluvium sites have hosted nearby nuclear tests, which provide comparisons for the chemical test data. Phase III of the SPE is yet to be determined. For Phase II of the experiment, characterization of the location is required to develop the geologic/geophysical models for the execution of the experiment. Criteria for the location are alluvium thickness of approximately 170 m and a water table below 170 m; minimal fracturing would be ideal. A P-wave mini-vibroseis survey was conducted at a potential site in alluvium to map out the subsurface geology. The seismic reflection profile consisted of 168 geophone stations, spaced 5 m apart. The mini-vibe was a 7,000-lb peak-force source, starting 57.5 m off the north end of the profile and ending 57.5 m past the southern-most geophone. The length of the profile was 835 m. The source points were placed every 5 m, equally spaced between geophones to reduce clipping. The vibroseis sweep was from 20 Hz down to 180 Hz over 8 seconds, and four sweeps were stacked at each shot location. The shot gathers show high signal-to-noise ratios with clear first arrivals across the entire spread and the suggestion of some shallow reflectors. The data were

  6. System and method for characterizing, synthesizing, and/or canceling out acoustic signals from inanimate sound sources

    Energy Technology Data Exchange (ETDEWEB)

    Holzrichter, John F; Burnett, Greg C; Ng, Lawrence C

    2013-05-21

    A system and method for characterizing, synthesizing, and/or canceling out acoustic signals from inanimate sound sources is disclosed. Propagating wave electromagnetic sensors monitor excitation sources in sound producing systems, such as machines, musical instruments, and various other structures. Acoustical output from these sound producing systems is also monitored. From such information, a transfer function characterizing the sound producing system is generated. From the transfer function, acoustical output from the sound producing system may be synthesized or canceled. The methods disclosed enable accurate calculation of matched transfer functions relating specific excitations to specific acoustical outputs. Knowledge of such signals and functions can be used to effect various sound replication, sound source identification, and sound cancellation applications.

  7. System and method for characterizing, synthesizing, and/or canceling out acoustic signals from inanimate sound sources

    Energy Technology Data Exchange (ETDEWEB)

    Holzrichter, John F. (Berkeley, CA); Burnett, Greg C. (Livermore, CA); Ng, Lawrence C. (Danville, CA)

    2007-10-16

    A system and method for characterizing, synthesizing, and/or canceling out acoustic signals from inanimate sound sources is disclosed. Propagating wave electromagnetic sensors monitor excitation sources in sound producing systems, such as machines, musical instruments, and various other structures. Acoustical output from these sound producing systems is also monitored. From such information, a transfer function characterizing the sound producing system is generated. From the transfer function, acoustical output from the sound producing system may be synthesized or canceled. The methods disclosed enable accurate calculation of matched transfer functions relating specific excitations to specific acoustical outputs. Knowledge of such signals and functions can be used to effect various sound replication, sound source identification, and sound cancellation applications.

  8. System and method for characterizing synthesizing and/or canceling out acoustic signals from inanimate sound sources

    Energy Technology Data Exchange (ETDEWEB)

    Holzrichter, John F. (Berkeley, CA); Burnett, Greg C. (Livermore, CA); Ng, Lawrence C. (Danville, CA)

    2003-01-01

    A system and method for characterizing, synthesizing, and/or canceling out acoustic signals from inanimate sound sources is disclosed. Propagating wave electromagnetic sensors monitor excitation sources in sound producing systems, such as machines, musical instruments, and various other structures. Acoustical output from these sound producing systems is also monitored. From such information, a transfer function characterizing the sound producing system is generated. From the transfer function, acoustical output from the sound producing system may be synthesized or canceled. The methods disclosed enable accurate calculation of matched transfer functions relating specific excitations to specific acoustical outputs. Knowledge of such signals and functions can be used to effect various sound replication, sound source identification, and sound cancellation applications.

  9. Extraction and Characterization of Tamarind (Tamarind indica L.) Seed Polysaccharides (TSP) from Three Difference Sources.

    Science.gov (United States)

    Chawananorasest, Khanittha; Saengtongdee, Patsuda; Kaemchantuek, Praphakorn

    2016-06-15

    Tamarind seed polysaccharide (TSP), a natural polysaccharide extracted from tamarind seeds is used in the pharmaceutical, textile and food industries as a mucoadhesive polymer. This work aimed to extract TSP from tamarind seeds from three sources with two methods and characterized its physical and chemical properties. Kernel powder of tamarind seeds was slurried into a clear solution, set aside overnight and then centrifuged at 6000 rpm for 20 min to separate all foreign matter. The supernatant was separated and poured into excess 95% ethanol with continuous stirring. The precipitate obtained was collected and dried in the oven and then the dried TSP polymer was stored in a desiccator. The dried TSP was analyzed by ¹H-NMR, FT-IR and XRD. The results showed TSP from tamarind seeds taken from paddy farmland (A), a waste from the export tamarind juice industry (B) and the export tamarind powder industry(C) gave yields of 31.55%, 26.95% and 17.30%, respectively, using method 1 and 11.15%, 53.65% and 54.65%, with method 2, respectively, but method 2 gave purer TSP than method 1. The FT-IR spectra displayed peaks at 3351.95 cm(-1), 2920.76 cm(-1), 1018.85 cm(-1) and 555.16 cm(-1). The ¹H-NMR showed polysaccharide peaks between δ 3.50-4.20 ppm and XRD diagrams indicated their amorphous nature. Future works will focus on the quantitative analysis, biological activity and possible use of TSP as a drug delivery system.

  10. Extraction and Characterization of Tamarind (Tamarind indica L. Seed Polysaccharides (TSP from Three Difference Sources

    Directory of Open Access Journals (Sweden)

    Khanittha Chawananorasest

    2016-06-01

    Full Text Available Tamarind seed polysaccharide (TSP, a natural polysaccharide extracted from tamarind seeds is used in the pharmaceutical, textile and food industries as a mucoadhesive polymer. This work aimed to extract TSP from tamarind seeds from three sources with two methods and characterized its physical and chemical properties. Kernel powder of tamarind seeds was slurried into a clear solution, set aside overnight and then centrifuged at 6000 rpm for 20 min to separate all foreign matter. The supernatant was separated and poured into excess 95% ethanol with continuous stirring. The precipitate obtained was collected and dried in the oven and then the dried TSP polymer was stored in a desiccator. The dried TSP was analyzed by 1H-NMR, FT-IR and XRD. The results showed TSP from tamarind seeds taken from paddy farmland (A, a waste from the export tamarind juice industry (B and the export tamarind powder industry(C gave yields of 31.55%, 26.95% and 17.30%, respectively, using method 1 and 11.15%, 53.65% and 54.65%, with method 2, respectively, but method 2 gave purer TSP than method 1. The FT-IR spectra displayed peaks at 3351.95 cm−1, 2920.76 cm−1, 1018.85 cm−1 and 555.16 cm−1. The 1H-NMR showed polysaccharide peaks between δ 3.50–4.20 ppm and XRD diagrams indicated their amorphous nature. Future works will focus on the quantitative analysis, biological activity and possible use of TSP as a drug delivery system.

  11. Initial source and site characterization studies for the U. C. San Diego campus

    Energy Technology Data Exchange (ETDEWEB)

    Day, S.; Erick, F.; Heuze, F.E.; Mellors, R.; Minster, B.; Park, S.; Wagoner, J.

    1999-07-01

    The basic approach of the Campus Laboratory Collaboration (CLC) project is to combine the substantial expertise that exists within the University of California (UC) system in geology, seismology, geotechnical engineering, and structural engineering to evaluate the effects of large earthquakes on UC facilities. These estimates draw upon recent advances in hazard assessment, seismic wave propagation modeling in rocks and soils, dynamic soil testing, and structural dynamics. The UC campuses currently chosen for applications of our integrated methodology are Riverside, San Diego, and Santa Barbara. The basic procedure is first to identify possible earthquake source regions and local campus site conditions that may affect estimates of strong ground motion. Combined geological , geophysical, and geotechnical studies are conducted to characterize each campus with specific focus on the location of particular target buildings of special interest to the campus administrators. The project will then drill and log deep boreholes next to the target structure, to provide direct in-situ measurements of subsurface material properties and to install uphole and downhole 3-component seismic sensors capable of recording both weak and strong motions. The boreholes provide access to deeper materials, below the soil layers, that have relatively high seismic shear-wave velocities. Analysis of conjugate downhole and uphole records provides a basis for optimizing the representation of the low-strain response of the sites. Earthquake rupture scenarios of identified causative faults are combined with the earthquake records and nonlinear soil models to provide site-specific estimates of strong motions at the selected target locations. The predicted ground motions are then used as input to the dynamic analysis of the buildings.

  12. Biological characterization of v. Cholerae-specific bacteriophages isolated from water sources in Georgia.

    Science.gov (United States)

    Elbakidze, T; Kokashvili, T; Janelidze, N; Porchkhidze, K; Koberidze, T; Tediashvili, M

    2015-03-01

    Vibrio cholerae, a widely spread bacterium in various marine, fresh, and brackish water environments, can cause a devastating diarrheal disease - cholera and also mild forms of gastroenteritis. Bacterial viruses are natural controllers of bacterial population density in water systems. The goal of this study was to isolate and characterize V. cholerae-specific bacteriophages occurring in the Georgian coastal zone of the Black Sea and inland water reservoirs in the eastern part of Georgia. During 2006-2009, 71 phages lytic to V. cholerae were collected from these aquatic environments. The phage isolation rate was varying from 8% to 15%, depending on the sampling season and site, and the abundance of host bacteria. The majority of phages specific to V. cholerae were collected from freshwater sources. The phage isolation showed seasonal character covering warm period -from April to September. Based on basic characteristics of primary phage isolates (lytic spectrum, virion morphology and DNA restriction profiles) 23 V. cholerae -specific phages were selected for series of consecutive screenings. Comparatively wide spectrum of lytic activity was revealed in case of 14 phages specific to V. cholerae O1, and one phage - VchBS3, active against non-O1 V. cholerae. Three phages active against V. cholerae non-O1 and six V. cholerae O1 -specific phages have been studied in detail for a number of biological features (stability in different solutions, temperature-, pH- and UV- sensitivity, influence of high ionic strength etc.), considered to be additional important characteristics for selection of phages with therapeutic potential.

  13. Measuring Spatial Variability of Vapor Flux to Characterize Vadose-zone VOC Sources: Flow-cell Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Mainhagu, Jon; Morrison, C.; Truex, Michael J.; Oostrom, Martinus; Brusseau, Mark

    2014-10-20

    A method termed vapor-phase tomography has recently been proposed to characterize the distribution of volatile organic contaminant mass in vadose-zone source areas, and to measure associated three-dimensional distributions of local contaminant mass discharge. The method is based on measuring the spatial variability of vapor flux, and thus inherent to its effectiveness is the premise that the magnitudes and temporal variability of vapor concentrations measured at different monitoring points within the interrogated area will be a function of the geospatial positions of the points relative to the source location. A series of flow-cell experiments was conducted to evaluate this premise. A well-defined source zone was created by injection and extraction of a non-reactive gas (SF6). Spatial and temporal concentration distributions obtained from the tests were compared to simulations produced with a mathematical model describing advective and diffusive transport. Tests were conducted to characterize both areal and vertical components of the application. Decreases in concentration over time were observed for monitoring points located on the opposite side of the source zone from the local–extraction point, whereas increases were observed for monitoring points located between the local–extraction point and the source zone. The results illustrate that comparison of temporal concentration profiles obtained at various monitoring points gives a general indication of the source location with respect to the extraction and monitoring points.

  14. Application of a Multidimensional Wavelet Denoising Algorithm for the Detection and Characterization of Astrophysical Sources of Gamma Rays

    Energy Technology Data Exchange (ETDEWEB)

    Digel, S.W.; /SLAC; Zhang, B.; Chiang, J.; /Maryland U.; Fadili, J.M.; /Caen U.; Starck, J.-L.; /Saclay /Stanford U., Statistics Dept.

    2005-12-02

    Zhang, Fadili, & Starck have recently developed a denoising procedure for Poisson data that offers advantages over other methods of intensity estimation in multiple dimensions. Their procedure, which is nonparametric, is based on thresholding wavelet coefficients. The restoration algorithm applied after thresholding provides good conservation of source flux. We present an investigation of the procedure of Zhang et al. for the detection and characterization of astrophysical sources of high-energy gamma rays, using realistic simulated observations with the Large Area Telescope (LAT). The LAT is to be launched in late 2007 on the Gamma-ray Large Area Space Telescope mission. Source detection in the LAT data is complicated by the low fluxes of point sources relative to the diffuse celestial background, the limited angular resolution, and the tremendous variation of that resolution with energy (from tens of degrees at {approx}30 MeV to 0.1{sup o} at 10 GeV). The algorithm is very fast relative to traditional likelihood model fitting, and permits immediate estimation of spectral properties. Astrophysical sources of gamma rays, especially active galaxies, are typically quite variable, and our current work may lead to a reliable method to quickly characterize the flaring properties of newly-detected sources.

  15. Physics-electrical hybrid model for real time impedance matching and remote plasma characterization in RF plasma sources

    Energy Technology Data Exchange (ETDEWEB)

    Sudhir, Dass, E-mail: dass.sudhir@iter-india.org; Bandyopadhyay, M.; Chakraborty, A. [ITER-India, Institute for Plasma Research, A-29 GIDC, Sec-25, Gandhinagar, 382016 Gujarat (India)

    2016-02-15

    Plasma characterization and impedance matching are an integral part of any radio frequency (RF) based plasma source. In long pulse operation, particularly in high power operation where plasma load may vary due to different reasons (e.g. pressure and power), online tuning of impedance matching circuit and remote plasma density estimation are very useful. In some cases, due to remote interfaces, radio activation and, due to maintenance issues, power probes are not allowed to be incorporated in the ion source design for plasma characterization. Therefore, for characterization and impedance matching, more remote schemes are envisaged. Two such schemes by the same authors are suggested in these regards, which are based on air core transformer model of inductive coupled plasma (ICP) [M. Bandyopadhyay et al., Nucl. Fusion 55, 033017 (2015); D. Sudhir et al., Rev. Sci. Instrum. 85, 013510 (2014)]. However, the influence of the RF field interaction with the plasma to determine its impedance, a physics code HELIC [D. Arnush, Phys. Plasmas 7, 3042 (2000)] is coupled with the transformer model. This model can be useful for both types of RF sources, i.e., ICP and helicon sources.

  16. Characterization of Choroidal Layers in Normal Aging Eyes Using Enface Swept-Source Optical Coherence Tomography.

    Directory of Open Access Journals (Sweden)

    Mehreen Adhi

    Full Text Available To characterize qualitative and quantitative features of the choroid in normal eyes using enface swept-source optical coherence tomography (SS-OCT.Fifty-two eyes of 26 consecutive normal subjects were prospectively recruited to obtain multiple three-dimensional 12 x 12 mm volumetric scans using a long-wavelength high-speed SS-OCT prototype. A motion-correction algorithm merged multiple SS-OCT volumes to improve signal. Retinal pigment epithelium (RPE was segmented as the reference and enface images were extracted at varying depths every 4.13 μm intervals. Systematic analysis of the choroid at different depths was performed to qualitatively assess the morphology of the choroid and quantify the absolute thicknesses as well as the relative thicknesses of the choroidal vascular layers including the choroidal microvasculature (choriocapillaris, terminal arterioles and venules; CC and choroidal vessels (CV with respect to the subfoveal total choroidal thickness (TC. Subjects were divided into two age groups: younger (<40 years and older (≥ 40 years.Mean age of subjects was 41.92 (24-66 years. Enface images at the level of the RPE, CC, CV, and choroidal-scleral interface were used to assess specific qualitative features. In the younger age group, the mean absolute thicknesses were: TC 379.4 μm (SD ± 75.7 μm, CC 81.3 μm (SD ± 21.2 μm and CV 298.1 μm (SD ± 63.7 μm. In the older group, the mean absolute thicknesses were: TC 305.0 μm (SD ± 50.9 μm, CC 56.4μm (SD ± 12.1 μm and CV 248.6μm (SD ± 49.7 μm. In the younger group, the relative thicknesses of the individual choroidal layers were: CC 21.5% (SD ± 4.0% and CV 78.4% (SD ± 4.0%. In the older group, the relative thicknesses were: CC 18.9% (SD ± 4.5% and CV 81.1% (SD ± 4.5%. The absolute thicknesses were smaller in the older age group for all choroidal layers (TC p=0.006, CC p=0.0003, CV p=0.03 while the relative thickness was smaller only for the CC (p=0.04.Enface SS-OCT at 1050

  17. The Ultraviolet Sky: final catalogs of unique UV sources from GALEX, and characterization of the UV-emitting sources across the sky, and of the Milky Way extinction

    Science.gov (United States)

    Bianchi, Luciana; Conti, A.; Shiao, B.; Keller, G. R.; Thilker, D. A.

    2014-01-01

    The legacy of the Galaxy Evolution Explorer (GALEX), which imaged the sky at Ultraviolet (UV) wavelengths for about 9 years, is its unprecedented database with more than 200 million source measurements in far-UV (FUV) and near-UV (NUV), as well as wide-field imaging of extended objects. GALEX's data, the first substantial sky surveys at UV wavelengths, offer an unprecedented view of the sky and a unique opportunity for an unbiased characterization of several classes of astrophysical objects, such as hot stars, QSOs at red-shift about 1, UV-peculiar QSOs, star-forming galaxies, among others. Bianchi et al. (2013, J. Adv. Space Res. (2013), DOI: http://dx.doi.org/10.1016/j.asr.2013.07.045) have constructed final catalogs of UV sources, with homogeneous quality, eliminating duplicate measurements of the same source ('unique' source catalogs), and excluding rim artifacts and bad photometry. The catalogs are constructed improving on the recipe of Bianchi et al. 2011 (MNRAS, 411, 2770, which presented the earlier version of these catalogs) and include all data for the major surveys, AIS and MIS. Considering the fields where both FUV and NUV detectors were exposed, the catalogs contain about 71 and 16.6 million unique sources respectively. We show several maps illustrating the content of UV sources across the sky, globally, and separately for bright/faint, hot, stellar/extragalactic objects. We matched the UV-source catalogs with optical-IR data from the SDSS, GSC2, 2MASS surveys. We are also in the process of matching the catalogs with preliminary PanSTARRS1 (PS1) 3pi survey photometry which already provides twice the sky coverage of SDSS, at slightly fainter magnitude limits. The sources' SED from FUV to optical wavelengths enables classification, derivation of the object physical parameters, and ultimately also a map of the Milky Way extinction. The catalogs will be available on MAST, Vizier (where the previous version already is), and in reduced form (for agile

  18. Attenuation-based characterization of coronary atherosclerotic plaque: Comparison of dual source and dual energy CT with single-source CT and histopathology

    International Nuclear Information System (INIS)

    Objective: To compare different CT acquisition techniques regarding for attenuation-based characterization of coronary atherosclerotic plaques using histopathology as the standard of reference. Materials and methods: In a post mortem study 17 human hearts were studied with dual-source CT (DSCT) and dual energy CT (DECT) mode on a DSCT as well as with 16-slice single-source CT (SSCT). At autopsy, atherosclerotic lesions were cut at 5 μm sections. Histopathologic classification of the plaques according to the American Heart Association (AHA) criteria was performed by two pathologists. Attenuation values of all plaques were measured in DSCT, DECT and SSCT studies, respectively and classified based on attenuation according to modified AHA criteria. Results: 58 coronary plaques were identified at autopsy. Regardless of the CT technique only 52/58 plaques were found at CT (sensitivity = 89.6%). There was no significant difference between the mean attenuation values of different plaque types between DSCT, DECT, and SSCT: type IV: 11 HU/8 HU/19 HU; type Va: 44 HU/45 HU/52 HU; type Vb: 1088 HU/966 HU/1079 HU). The sensitivity for correct classification varied depending on the plaque type (type II = 0%, type III = 0%, type IV = 43%, type Va = 58%, Vb = 97%). Conclusion: Independent of the used acquisition technique, SSCT, DSCT and DECT show similar results for attenuation-based characterization of atherosclerotic coronary plaques.

  19. A study on the characterization of smoke movement in shafts with different fire source positions

    Institute of Scientific and Technical Information of China (English)

    Zhu Jie; Yang Tianyou; Wu Jianbo; Du Lulu

    2013-01-01

    In this study,experimental and numerical simulation methods were combined to simulate the changing course of the temperature and velocity fields in nine different fire scenes. The characteristics of smoke movement in shafts with different fire source position factors (h/H) were quantitatively investigated,and the non-dimensional fitting function between the fire source position factors and the maximum temperature was deduced. The results showed that the location of the neutral plane moved upward as the fire source rose,and all the generated smoke spread to the upper areas;however,there was barely any smoke in the lower areas. The maximum temperature was inversely proportional to the fire source position factor;the higher the source position is,i.e. the higher the ra-tio factor is,the lower the maximum temperature is in the shaft. The experimental verification of the fire dynamics simulator (FDS) showed good results.

  20. ISOLATION, SCREENING, CHARACTERIZATION AND DETERMINATION OF B-COMPLEX VITAMINS BY LACTOBACILLUS STRAINS FROM DIFFERENT SOURCES OF MEAT

    OpenAIRE

    Abishek Manisagar

    2012-01-01

    In this study, isolation, screening, characterization, antibiotic susceptibility tests, curing & Determination of B-complex vitamin production by potent probiotic Lactobacillus strains from different sources of meat was analysed. 250 grams of intestine parts of goat meat and beef each were transferred to MRS broth to screen the potent probiotic Lactobacillus strains. Initially 57 strains were isolated and confirmed by gram`s staining and catalase tests. After that, 51 strains selected for fur...

  1. Lead isotopic fingerprinting of aerosols to characterize the sources of atmospheric lead in an industrial city of India

    Science.gov (United States)

    Sen, Indra S.; Bizimis, Michael; Tripathi, Sachchida Nand; Paul, Debajyoti

    2016-03-01

    Anthropogenic Pb in the environment is primarily sourced from combustion of fossil fuel and high-temperature industries such as smelters. Identifying the sources and pathways of anthropogenic Pb in the environment is important because Pb toxicity is known to have adverse effects on human health. Pb pollution sources for America, Europe, and China are well documented. However, sources of atmospheric Pb are unknown in India, particularly after leaded gasoline was phased out in 2000. India has a developing economy with a rapidly emerging automobile and high temperature industry, and anthropogenic Pb emission is expected to rise in the next decade. In this study, we report on the Pb-isotope compositions and trace metal ratios of airborne particulates collected in Kanpur, a large city in northern part of India. The study shows that the PM10 aerosols had elevated concentration of Cd, Pb, Zn, As, and Cu in the Kanpur area, however their concentrations are well below the United States Environmental Protection Agency chronic exposure limit. Lead isotopic and trace metal data reveal industrial emission as the plausible source of anthropogenic Pb in the atmosphere in Kanpur. However, Pb isotopic compositions of potential source end-members are required to fully evaluate Pb contamination in India over time. This is the first study that characterizes the isotopic composition of atmospheric Pb in an Indian city after leaded gasoline was phased out by 2000.

  2. Fecal pollution source tracking toolbox for identification, evaluation and characterization of fecal contamination in receiving urban surface waters and groundwater.

    Science.gov (United States)

    Tran, Ngoc Han; Gin, Karina Yew-Hoong; Ngo, Huu Hao

    2015-12-15

    The quality of surface waters/groundwater of a geographical region can be affected by anthropogenic activities, land use patterns and fecal pollution sources from humans and animals. Therefore, the development of an efficient fecal pollution source tracking toolbox for identifying the origin of the fecal pollution sources in surface waters/groundwater is especially helpful for improving management efforts and remediation actions of water resources in a more cost-effective and efficient manner. This review summarizes the updated knowledge on the use of fecal pollution source tracking markers for detecting, evaluating and characterizing fecal pollution sources in receiving surface waters and groundwater. The suitability of using chemical markers (i.e. fecal sterols, fluorescent whitening agents, pharmaceuticals and personal care products, and artificial sweeteners) and/or microbial markers (e.g. F+RNA coliphages, enteric viruses, and host-specific anaerobic bacterial 16S rDNA genetic markers) for tracking fecal pollution sources in receiving water bodies is discussed. In addition, this review also provides a comprehensive approach, which is based on the detection ratios (DR), detection frequencies (DF), and fate of potential microbial and chemical markers. DR and DF are considered as the key criteria for selecting appropriate markers for identifying and evaluating the impacts of fecal contamination in surface waters/groundwater.

  3. The Development of Testing Methods for Characterizing Emissions and Sources of Exposures from Polyurethane Products

    Science.gov (United States)

    The relationship between onsite manufacture of spray polyurethane foam insulation (SPFI) and potential exposures is not well understood. Currently, no comprehensive standard test methods exist for characterizing and quantifying product emissions. Exposures to diisocyanate compoun...

  4. Semi-Empirical Characterization of Ground Motions Including Source, Path and Nonlinear Site Effects

    Science.gov (United States)

    Seyhan, Emel

    The objective of this thesis is to improve the physical understanding of earthquake ground motion characteristics related to source, path and nonlinear site effects and our ability to model those effects with engineering models. Site database work was performed within the context of the NGA-West 2 project. Starting with the site database from original (2008) NGA project (last edited in 2006), we provided site classifications for 2538 new sites and re-classifications of previous sites. The principal site parameter is the time-averaged shear wave velocity in the upper 30 m (Vs30 ), which is characterized using measurements where available, and proxy-based relationships otherwise. We improved the documentation and consistency of site descriptors used as proxies for the estimation of Vs30, developed evidence-based protocols for Vs30 estimation from available proxies, and augmented estimates of various basin depth parameters. Site factors typically have a small-strain site amplification that captures impedance and resonance effects coupled with nonlinear components. Site factors in current NEHRP Provisions are empirically-derived at relatively small ground motion levels and feature simulation-based nonlinearity. We show that current NEHRP site factors have discrepancies with respect to the site terms in the original NGA GMPEs both in the linear site amplification (especially for Classes B, C, D, and E) and the degree of nonlinearity (Classes C and D). We analyzed the NGA-West 2 dataset and simulation-based models for site amplification to develop a new model. The model has linear and nonlinear additive components. The linear component is fully empirical, being derived from worldwide ground motion data (regional effects were examined but found to not be sufficiently important to be included in the model). The model features linear Vs30-scaling in a log-log sense below a corner velocity (Vc), and no Vs30-scaling for velocities faster than Vc. The nonlinear component is

  5. Characterization of vancomycin resistant Enterococcus faecium from clinical and chicken sources

    Institute of Scientific and Technical Information of China (English)

    Asha Peter; Radhakrishnan EK; Jyothis Mathew; Shini Zacharia

    2012-01-01

    Objective: The study was undertaken to investigate the genomic and phenotypic relationship among E.faecium strains isolated from chicken and clinical sources. Methods: Enterococci were isolated and identified by conventional biochemical methods and the antibiotic susceptibility was determined by disk diffusion methods. Phenotypes and genotypes of vancomycin resistance were detected by E tests and PCR amplification techniques respectively. Genotyping of the vancomycin resistant E.faecium from two sources were done by RAPD typing. Results: The Vancomycin resistant E.faecium identified was selected for this comparative study. Among the VREF from two sources minor biochemical difference with regards to raffinose fermentation and haemolytic properties was observed. The RAPD tests using random primers also showed polymorphism. Conclusion: The results of the study showed that the strains from two different sources were not identical.

  6. Characterization of volume type ion source for $p$, $H_2^+$ and $H_3^+$ beams

    CERN Document Server

    Joshi, N; Meusel, O; Ratzinger, U

    2016-01-01

    Recently, there is an increasing need for $H_{2}^+$ and $H_{3}^+$ ion sources. One example are ion therapy facilities, where $C^{4+}$ and $H_{3}^+$ ion beams along the linac are of great interest. Another example is a $H_{2}^+$ test beam for linacs finally operated with intense deuteron beams. At Frankfurt, a simple proton ion source is needed to test a new kind of beam injection into a magnetic storage ring\\cite{EPAC08}\\cite{EPAC06}. This article describes a volume type ion source which can deliver upto $3.05~mA$ beam current at $10~keV$ in stable dc operation. It is a hot filament driven ion source which can provide high fractions of $p$, $H_{2}^+$ or $H_{3}^+$, depending on the operation settings.

  7. UNMIX Methods Applied to Characterize Sources of Volatile Organic Compounds in Toronto, Ontario

    Directory of Open Access Journals (Sweden)

    Eugeniusz Porada

    2016-06-01

    Full Text Available UNMIX, a sensor modeling routine from the U.S. Environmental Protection Agency (EPA, was used to model volatile organic compound (VOC receptors in four urban sites in Toronto, Ontario. VOC ambient concentration data acquired in 2000–2009 for 175 VOC species in four air quality monitoring stations were analyzed. UNMIX, by performing multiple modeling attempts upon varying VOC menus—while rejecting the results that were not reliable—allowed for discriminating sources by their most consistent chemical characteristics. The method assessed occurrences of VOCs in sources typical of the urban environment (traffic, evaporative emissions of fuels, banks of fugitive inert gases, industrial point sources (plastic-, polymer-, and metalworking manufactures, and in secondary sources (releases from water, sediments, and contaminated urban soil. The remote sensing and robust modeling used here produces chemical profiles of putative VOC sources that, if combined with known environmental fates of VOCs, can be used to assign physical sources’ shares of VOCs emissions into the atmosphere. This in turn provides a means of assessing the impact of environmental policies on one hand, and industrial activities on the other hand, on VOC air pollution.

  8. Groundwater flow dynamics and arsenic source characterization in an aquifer system of West Bengal, India

    Science.gov (United States)

    Desbarats, A. J.; Koenig, C. E. M.; Pal, T.; Mukherjee, P. K.; Beckie, R. D.

    2014-06-01

    Numerical groundwater flow modeling, reverse particle tracking, and environmental tracers are used to locate the source of geogenic As affecting an aquifer in West Bengal. The aquifer is hosted by point-bar sands deposited in a meandering fluvial environment. Wells tapping the aquifer exhibit As concentrations up to 531 μg/L. High-As groundwaters are recharged in ponds marking an abandoned river channel. The source of As is traced to the underlying fine-grained channel-fill sediments. Arsenic release within these sediments is accompanied by a concomitant release of Br and DOC indicating that these species may be decay products of natural organobromines codeposited along with As. Mass transfer of As to the dissolved phase and its flushing from source sediments are described using a simplified reactive solute transport model. Based on this model, a characteristic reaction time for mass transfer is estimated at 6.7 years. Average groundwater residence times in the source are estimated to have declined from 16.6 to 6.6 years with the advent of intensive irrigation pumping. The ratio of residence and reaction times, a Damköhler number, has declined correspondingly from 2.49 to 0.99, indicating a shift from transport to reaction rate limited As mobilization. Greater insight into the As problem in SE Asia may be achieved by shifting the focus of field investigations from aquifers to potential contamination sources in aquitards.

  9. Characterization of domestic gray water from point source to determine the potential for urban residential reuse: a short review

    Science.gov (United States)

    Edwin, Golda A.; Gopalsamy, Poyyamoli; Muthu, Nandhivarman

    2014-03-01

    This study aims to discern the domestic gray water (GW) sources that is least polluting, at the urban households of India, by examining the GW characteristics, comparing with literature data, reuse standards and suitable treatment technologies. In view of this, the quantitative and qualitative characteristics of domestic GW originating from bath, wash basin, laundry and kitchen sources are determined and compared with established standards for reuse requirements. Quality of different gray water sources is characterized with respect to the physical, chemical, biological, nutrient, ground element and heavy metal properties. The pollutant loads indicate that the diversion techniques are not suitable for household application and, therefore, treatment is necessary prior to storage and reuse. It is observed that the total volume of GW generated exceeds the reuse requirement for suggested reuse such as for flushing and gardening/irrigation. In spite of generating less volume, the kitchen source is found to be the major contributor for most of the pollutant load and, therefore, not recommended to be considered for treatment. It is concluded that treatment of GW from bathroom source alone is sufficient to meet the onsite reuse requirements and thereby significantly reduce the potable water consumption by 28.5 %. Constructed wetland systems and constructed soil filters are suggested as suitable treatment alternatives owing to its ability to treat highly variable pollutant load with lower operational and maintenance cost, which is more practical for tropical and developing countries.

  10. Characterization of a metastable neon beam extracted from a commercial RF ion source

    International Nuclear Information System (INIS)

    We have used a commercial RF ion-source to extract a beam of metastable neon atoms. The source was easily incorporated into our existing system and was operative within a day of installation. The metastable velocity distribution, flux, flow, and efficiency were investigated for different RF powers and pressures, and an optimum was found at a flux density of 2 × 1012 atoms/s/sr. To obtain an accurate measurement of the amount of metastable atoms leaving the source, we insert a Faraday cup in the beam line and quench some of them using a weak 633 nm laser beam. In order to determine how much of the beam was quenched before reaching our detector, we devised a simple model for the quenching transition and investigated it for different laser powers. This detection method can be easily adapted to other noble gas atoms

  11. Characterization of a metastable neon beam extracted from a commercial RF ion source

    CERN Document Server

    Ohayon, B; Ron, G

    2015-01-01

    We have used a commercial RF ion-source to extract a beam of metastable neon atoms. The source was easily incorporated into our existing system and was operative within a day of installation. The metastable velocity distribution, flux, flow, and efficiency were investigated for different RF powers and pressures, and an optimum was found at a flux density of $2\\times10^{12}\\,$atoms/s/sr. To obtain an accurate measurement of the amount of metastable atoms leaving the source, we insert a Faraday cup in the beam line and quench some of them using a weak $633\\,$nm laser beam. In order to determine how much of the beam was quenched before reaching our detector, we devised a simple model for the quenching transition and investigated it for different laser powers. This detection method can be easily adapted to other noble gas atoms.

  12. Characterization of a {sup 239}PuBe isotopic neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H. R.; Hernandez D, V. M. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Calz. Legaria No. 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Sanchez, A., E-mail: fermineutron@yahoo.com [IPN, Escuela Superior de Fisica y Matematicas, 07738 Mexico D. F. (Mexico)

    2012-10-15

    A Bonner sphere spectrometer was used to determine the features of a {sup 239}PuBe neutron source used to operate the ESFM-Ipn Subcritical Reactor. The spectrometer is a {sup 6}Lil(Eu) scintillator and 2, 3, 5, 8, 10 and 12 inches-diameter polyethylene spheres, that was located 100 cm from the neutron source. The count rates obtained with the spectrometer were unfolded using the NSDUAZ code and neutron spectrum, total fluence, and ambient dose equivalent were determined. A Monte Carlo calculation, using the MCNP5 code, was carried out to estimate the spectrum and integral features being less that values obtained experimentally due to the presence of {sup 241}Pu in the Pu used to fabricate the source. Using the experimental information the actual neutron yield and the mass fraction of {sup 241}Pu was estimated. (Author)

  13. In Silico Characterization of Pectate Lyase Protein Sequences from Different Source Organisms

    Directory of Open Access Journals (Sweden)

    Amit Kumar Dubey

    2010-01-01

    Full Text Available A total of 121 protein sequences of pectate lyases were subjected to homology search, multiple sequence alignment, phylogenetic tree construction, and motif analysis. The phylogenetic tree constructed revealed different clusters based on different source organisms representing bacterial, fungal, plant, and nematode pectate lyases. The multiple accessions of bacterial, fungal, nematode, and plant pectate lyase protein sequences were placed closely revealing a sequence level similarity. The multiple sequence alignment of these pectate lyase protein sequences from different source organisms showed conserved regions at different stretches with maximum homology from amino acid residues 439–467, 715–816, and 829–910 which could be used for designing degenerate primers or probes specific for pectate lyases. The motif analysis revealed a conserved Pec_Lyase_C domain uniformly observed in all pectate lyases irrespective of variable sources suggesting its possible role in structural and enzymatic functions.

  14. Characterization of an old municipal landfill (Grindsted, Denmark) as a groundwater pollution source

    DEFF Research Database (Denmark)

    Kjeldsen, Peter; Grundtvig, Aase; Winther, Pia;

    1998-01-01

    Investigations into the pollution of groundwater from old landfill have, in most cases, focused on delineating the pollution plume rather than on the landfill as a source of groundwater pollution. Landfills often cover large areas and spatial variations in leachate composition within the landfill...... variations in leachate composition are very important for locating the main source of the groundwater pollution and for selection of cost-effective remedial action activities.......Investigations into the pollution of groundwater from old landfill have, in most cases, focused on delineating the pollution plume rather than on the landfill as a source of groundwater pollution. Landfills often cover large areas and spatial variations in leachate composition within the landfill...... were evaluated. A pronounced variability in leachate composition was observed in the 31 leachate wells installed through the waste. The spatial variability was analysed by statistical methods, and a semivariogram model was able to describe the variability both on small and large scale. The spatial...

  15. Characterization of the Theta to Beta Ratio in ADHD: Identifying Potential Sources of Heterogeneity

    Science.gov (United States)

    Loo, Sandra K.; Cho, Alexander; Hale, T. Sigi; McGough, James; McCracken, James; Smalley, Susan L.

    2013-01-01

    Objective: The goal of this study is to characterize the theta to beta ratio (THBR) obtained from electroencephalogram (EEG) measures, in a large sample of community and clinical participants with regard to (a) ADHD diagnosis and subtypes, (b) common psychiatric comorbidities, and (c) cognitive correlates. Method: The sample includes 871…

  16. The development and characterization of ion exchange membranes for selected electrochemical power sources

    Science.gov (United States)

    Arnold, C., Jr.; Assink, R. A.

    The work is reviewed on the development and characterization of ion exchange membranes in an effort to improve the efficiency of three flowing electrolyte batteries. The batteries are: (1) NASA's iron chromium redox battery; (2) Lockheed's zinc ferricyanide battery; and (3) Johnson Control's zinc bromine battery. These batteries were developed for solar photovoltaic, utility load leveling, and electric vehicle applications, respectively.

  17. Integration of semi-automatic detection and sediment connectivity assessment for the characterization of sediment source areas in mountain catchments

    Science.gov (United States)

    Crema, Stefano; Bossi, Giulia; Marchi, Lorenzo; Cavalli, Marco

    2016-04-01

    Identifying areas that are directly delivering sediment to the channel network or to a catchment outlet is of great importance for a sound sediment dynamic characterization and for assessing sediment budget. We present an integration of remote sensing analysis techniques to characterize the effective sediment contributing area that is the sub-portion of the catchment in which sediment is effectively routed towards the catchment outlet. A semi-automatic mapping of active sediment source areas is carried out via image analysis techniques. To this purpose, satellite multispectral images and aerial orthophotos are considered for the analysis. Several algorithms for features extraction are applied and the maps obtained are compared with an expert-based sediment source mapping derived from photointerpretation and field surveys. The image-based analysis is additionally integrated with a topography-driven filtering procedure. Thanks to the availability of High-Resolution, LiDAR-derived Digital Terrain Models, it is possible to work at a fine scale and to compute morphometric parameters (e.g., slope, roughness, curvature) suitable for refining the image analysis. In particular, information on local topography was integrated with the image-based analysis to discriminate between rocky outcrops and sediment sources, thus improving the overall consistency of the procedure. The sediment source areas are then combined with the output of a connectivity assessment. A topography-based index of sediment connectivity is computed for the analyzed areas in order to better estimate the effective sediment contributing area and to obtain a ranking of the source areas in the studied catchments. The study methods have been applied in catchments of the Eastern Italian Alps where a detailed census of sediment source areas is available. The comparison of the results of image analysis with expert-based sediment sources mapping shows a satisfactory agreement between the two approaches

  18. Spectral and timing characterization of the X-ray source 1RXS J194211.9+255552

    CERN Document Server

    D'Aì, A; La Parola, V; Segreto, A

    2016-01-01

    We report on the first spectral and timing characterization of the transient X-ray source 1RXS J194211.9+255552 using all available data from the Swift X-ray satellite. We used 10 years of hard X-ray data from the Burst Alert Telescope (BAT) to characterize its long-term behaviour and to search for long periodicities, finding evidence for a periodic modulation at 166.5 $\\pm$ 0.5 d, that we interpret as the orbital period of the source. The folded light curve reveals that the X-ray emission is mostly concentrated in a restricted phase-interval and we propose to associate 1RXS J194211.9+255552 to the class of the Be X-ray binaries. This is also supported by the results of the spectral analysis, where we used the BAT data and three pointed Swift/XRT observations to characterize the X-ray broad-band spectral shape. We found mild spectral variability in soft X-rays that can be accounted for by a varying local neutral absorber, while the intrinsic emission is consistent with a hard power law multiplied by a high-en...

  19. Overall hydrochemical characterization of the Iberian Pyrite Belt. Main acid mine drainage-generating sources (Huelva, SW Spain)

    Science.gov (United States)

    Grande, J. A.; de la Torre, M. L.; Cerón, J. C.; Beltrán, R.; Gómez, T.

    2010-09-01

    SummaryAMD is an anthropogenic process caused by sulfide mineralization and the increase in the contact surface due to mining activity and grain-size reduction. In Spain, the contamination comes from the metal sulfide mines in the Iberian Pyrite Belt (IPB). Spreading over an area 230 km long and approximately 50 km wide, it is one of the largest metallogenic regions in the world, with massive sulfide reserves of about 1700 Mt. In the present study we will characterize AMD contamination processes in the IPB, especially by As, by identifying the sources responsible for these processes (active mines and effluents from mines and slag heaps) in the basins of the Tinto and Odiel rivers. It is also the aim of this study to discover the mineral associations of the deposits. The study of the AMD process generating source is complemented with hydrochemical characterization of the effluents produced, which will be carried out by means of sample-taking and subsequent chemical analysis and statistical treatment (cluster analysis). Characteristics in common with samples taken in other AMD-affected watercourses are observed in the seven zones defined in the study area. With respect to the samples studied, obvious differences can also be found. These differences are inherent to the mineral associations, watershed and distance to the generating source and, ultimately, to the affected area, and the type, intensity and duration of the mine treatment process developed in the acid-producing area.

  20. Production and characterization of 228Th calibration sources with low neutron emission for GERDA

    Science.gov (United States)

    Baudis, L.; Benato, G.; Carconi, P.; Cattadori, C.; De Felice, P.; Eberhardt, K.; Eichler, R.; Petrucci, A.; Tarka, M.; Walter, M.

    2015-12-01

    The GERDA experiment at the Laboratori Nazionali del Gran Sasso (LNGS) searches for the neutrinoless double beta decay of 76Ge. In view of the GERDA Phase II data collection, four new 228Th radioactive sources for the calibration of the germanium detectors enriched in 76Ge have been produced with a new technique, leading to a reduced neutron emission rate from (α, n) reactions. The gamma activities of the sources were determined with a total uncertainty of ~4% using an ultra-low background HPGe detector operated underground at LNGS. The neutron emission rate was determined using a low background LiI(Eu) detector and a 3He counter at LNGS. In both cases, the measured neutron activity is ~10-6 n/(sṡBq), with a reduction of about one order of magnitude with respect to commercially available 228Th sources. Additionally, a specific leak test with a sensitivity to leaks down to ~10 mBq was developed to investigate the tightness of the stainless steel capsules housing the sources after their use in cryogenic environment.

  1. Production and characterization of 228Th calibration sources with low neutron emission for GERDA

    International Nuclear Information System (INIS)

    The GERDA experiment at the Laboratori Nazionali del Gran Sasso (LNGS) searches for the neutrinoless double beta decay of 76Ge. In view of the GERDA Phase II data collection, four new 228Th radioactive sources for the calibration of the germanium detectors enriched in 76Ge have been produced with a new technique, leading to a reduced neutron emission rate from (α, n) reactions. The gamma activities of the sources were determined with a total uncertainty of ∼4% using an ultra-low background HPGe detector operated underground at LNGS. The neutron emission rate was determined using a low background LiI(Eu) detector and a 3He counter at LNGS. In both cases, the measured neutron activity is ∼10−6 n/(s⋅Bq), with a reduction of about one order of magnitude with respect to commercially available 228Th sources. Additionally, a specific leak test with a sensitivity to leaks down to ∼10 mBq was developed to investigate the tightness of the stainless steel capsules housing the sources after their use in cryogenic environment

  2. Characterization and source identification of stormwater runoff in tropical urban catchments.

    Science.gov (United States)

    Chow, M F; Yusop, Z

    2014-01-01

    The characteristics of urban stormwater pollution in the tropics are still poorly understood. This issue is crucial to the tropical environment because its rainfall and runoff generation processes are so different from temperate regions. In this regard, a stormwater monitoring program was carried out at three urban catchments (e.g. residential, commercial and industrial) in the southern part of Peninsular Malaysia. A total of 51 storm events were collected at these three catchments. Samples were analyzed for total suspended solids, 5-day biochemical oxygen demand, chemical oxygen demand (COD), oil and grease, nitrate nitrogen, nitrite nitrogen, ammonia nitrogen (NH3-N), soluble reactive phosphorus and total phosphorus. Principal component analysis (PCA) and hierarchical cluster analysis were used to interpret the stormwater quality data for pattern recognition and identification of possible sources. The most likely sources of stormwater pollutants at the residential catchment were from surface soil and leachate of fertilizer from domestic lawns and gardens, whereas the most likely sources for the commercial catchment were from discharges of food waste and washing detergent. In the industrial catchment, the major sources of pollutants were discharges from workshops and factories. The PCA factors further revealed that COD and NH3-N were the major pollutants influencing the runoff quality in all three catchments. PMID:24473291

  3. Development and characterization of a high-reliability, extended-lifetime H- ion source

    Science.gov (United States)

    Becerra, Gabriel; Barrows, Preston; Sherman, Joseph

    2015-11-01

    Phoenix Nuclear Labs (PNL) has designed and constructed a long-lifetime, negative hydrogen (H-) ion source, in partnership with Fermilab for an ion beam injector servicing future Intensity Frontier particle accelerators. The specifications for the low-energy beam transport (LEBT) section are 5-10 mA of continuous H- ion current at 30 keV with PNL's design features an electron cyclotron resonance (ECR) microwave plasma driver which has been extensively developed in positive ion source systems, having demonstrated 1000+ hours of operation and >99% continuous uptime at PNL. Positive ions and hyperthermal neutrals drift toward a low-work-function surface, where a fraction is converted into H- hydrogen ions, which are subsequently extracted into a low-energy beam using electrostatic lenses. A magnetic filter preferentially removes high-energy electrons emitted by the source plasma, in order to mitigate H- ion destruction via electron-impact detachment. The design of the source subsystems and preliminary diagnostic results will be presented.

  4. Characterization of disinfection byproduct formation potential in 13 source waters in China

    Institute of Scientific and Technical Information of China (English)

    Junzhi Zhang; Jianwei Yu; Wei An; Juan Liu; Yongjing Wang; Youjun Chen; Jia Tai; Min Yang

    2011-01-01

    The formation potential of four trihalomethanes (THMFP) and seven haloacetic acids (HAA7FP) in 13 source waters taken from four major water basin areas in China was evaluated using the simulated distribution system (SDS) chlorination method.The specific ultraviolet absorbance (SUVA254: the ratio of UV254 to dissolved organic carbon (DOC)), which ranged between 0.9 and 5.0 L/(mg·m), showed that the organic compounds in different source waters exhibited different reactivities with chlorine.The HAA7FP of source waters ranged from 20 to 448 μg/L and the THMFP ranged from 29 to 259 μg/L.The HAA7FP concentrations were higher than the THMFP concentrations in all but one of the samples.Therefore, the risks of haloacetic acids (HAAs) should be of concern in some source waters.TCM (chloroform) and BDCM (bromodichloromethane) were the major THM constituents, while TCAA (trichioroacetic acid) and DCAA (dichloroacetic acid) were the major HAA species.Br-THM (brominated THM species) were much higher than BrHAA (brominated HAA species), and the formation of Br-DBP (Br-THM and Br-HAA) should be of concern when the bromide concentration is over 100 μg/L.

  5. Long period seismic source characterization at Popocatépetl volcano, Mexico

    Science.gov (United States)

    Arciniega-Ceballos, Alejandra; Dawson, Phillip; Chouet, Bernard A.

    2012-01-01

    The seismicity of Popocatépetl is dominated by long-period and very-long period signals associated with hydrothermal processes and magmatic degassing. We model the source mechanism of repetitive long-period signals in the 0.4–2 s band from a 15-station broadband network by stacking long-period events with similar waveforms to improve the signal-to-noise ratio. The data are well fitted by a point source located within the summit crater ~250 m below the crater floor and ~200 m from the inferred magma conduit. The inferred source includes a volumetric component that can be modeled as resonance of a horizontal steam-filled crack and a vertical single force component. The long-period events are thought to be related to the interaction between the magmatic system and a perched hydrothermal system. Repetitive injection of fluid into the horizontal fracture and subsequent sudden discharge when a critical pressure threshold is met provides a non-destructive source process.

  6. Production and Characterization of 228Th Calibration Sources with Low Neutron Emission for GERDA

    CERN Document Server

    Baudis, Laura; Carconi, Pierluigi; Cattadori, Carla Maria; De Felice, Pierino; Eberhardt, Klaus; Eichler, Robert; Petrucci, Andrea; Tarka, Michal; Walter, Manuel

    2015-01-01

    The GERDA experiment at the Laboratori Nazionali del Gran Sasso (LNGS) searches for the neutrinoless double beta decay of 76-Ge. In view of the GERDA Phase II data collection, four new 228-Th radioactive sources for the calibration of the germanium detectors enriched in 76-Ge have been produced with a new technique, leading to a reduced neutron flux from ( alpha; n ) reactions. The gamma activities of the sources were determined with a total uncertainty of 4 percent using an ultra-low background HPGe detector operated underground at LNGS. The emitted neutron flux was determined using a low background LiI(Eu) detector and a 3-He counter at LNGS. In both cases, a reduction of about one order of magnitude with respect to commercially available 228-Th sources was obtained. Additionally, a specific leak test with a sensitivity to leaks down to 10 mBq was developed to investigate the tightness of the stainless steel capsules housing the sources after their use in cryogenic environment.

  7. Molecular marker characterization and source appointment of particulate matter and its organic aerosols.

    Science.gov (United States)

    Choi, Jong-Kyu; Ban, Soo-Jin; Kim, Yong-Pyo; Kim, Yong-Hee; Yi, Seung-Muk; Zoh, Kyung-Duk

    2015-09-01

    This study was carried out to identify possible sources and to estimate their contribution to total suspended particle (TSP) organic aerosol (OA) contents. A total of 120 TSP and PM2.5 samples were collected simultaneously every third day over a one-year period in urban area of Incheon, Korea. High concentration in particulate matters (PM) and its components (NO3(-), water soluble organic compounds (WSOCs), and n-alkanoic acids) were observed during the winter season. Among the organics, n-alkanes, n-alkanoic acids, levoglucosan, and phthalates were major components. Positive matrix factorization (PMF) analysis identified seven sources of organic aerosols including combustion 1 (low molecular weight (LMW)-polycyclic aromatic hydrocarbons (PAHs)), combustion 2 (high molecular weight (HMW)-PAHs), biomass burning, vegetative detritus (n-alkane), secondary organic aerosol 1 (SOA1), secondary organic aerosol 2 (SOA2), and motor vehicles. Vegetative detritus increased during the summer season through an increase in biogenic/photochemical activity, while most of the organic sources were prominent in the winter season due to the increases in air pollutant emissions and atmospheric stability. The correlation factors were high among the main components of the organic carbon (OC) in the TSP and PM2.5. The results showed that TSP OAs had very similar characteristics to the PM2.5 OAs. SOA, combustion (PAHs), and motor vehicle were found to be important sources of carbonaceous PM in this region. Our results imply that molecular markers (MMs)-PMF model can provide useful information on the source and characteristics of PM. PMID:26022138

  8. Characterizing the Source Water for Montane Meadows to Assess Resiliency under Changing Hydroclimatic Condition

    Science.gov (United States)

    Yarnell, S. M.; Peek, R.; Bell, A.; Weixelman, D.; Viers, J. H.

    2015-12-01

    Ecologically and hydrologically functioning montane meadows provide a variety of ecosystem services and create biological hotspots in high-elevation landscapes. They serve as wetlands that filter water, attenuate floods, sequester carbon, sustain downstream flows, and provide high productivity habitat in typically lower productivity mountain regions. Their importance to watershed quality and health is well recognized, and restoration of meadows is a high priority for resource management agencies and non-governmental organizations. Yet many meadow restoration projects have limited outcomes or fail to achieve the desired effects due to a lack of understanding the underlying hydrological and geomorphic processes inherent to meadows that contribute to their resiliency. Few studies exist on how meadows are sustained through time despite various land use impacts or how the origin of water supplying the meadow (snowmelt-dominated versus regional groundwater-dominated) may influence meadow conditions. Furthermore, as climate conditions continue to change, questions remain regarding which meadows will be most resistant to and resilient from climate warming and thus have the highest potential for successful and sustainable restoration of meadow processes. We discuss these concepts and present two methods for assessing the regional and local contributions of source water to meadows as an indicator of resiliency. On a broad scale, comparisons of satellite imagery using metrics such as normalized difference vegetation index (NDVI) for regions with meadows may be useful to detect inter-annual and seasonal variations in meadow wetness and thus indicate meadow sites with larger groundwater sources that are more resilient over time. Locally, use of a hydrogeomorphic typing key that relates water source, geomorphic position, groundwater table elevation, and plant species composition may be useful to detect local groundwater sources that provide greater consistency of conditions and

  9. Sources and chemical characterization of organic aerosol during the summer in the eastern Mediterranean

    Directory of Open Access Journals (Sweden)

    E. Kostenidou

    2015-02-01

    Full Text Available The concentration and chemical composition of the non-refractory fine particulate matter (NR-PM1 and black carbon (BC levels were measured during the summer of 2012 in the suburbs of two Greek cities, Patras and Athens, in an effort to better understand the chemical processing of particles in the high photochemical activity environment of the Eastern Mediterranean. The composition of PM1 was surprisingly similar in both areas demonstrating the importance of regional sources for the corresponding pollution levels. The PM1 average mass concentration was 9–14 μg m−3. The contribution of sulphate was around 38%, while organic aerosol (OA contributed approximately 45% in both cases. PM1 nitrate levels were low (2%. The oxygen to carbon (O : C atomic ratio was 0.50 ± 0.08 in Patras and 0.47 ± 0.11 in Athens. In both cases the PM1 was acidic. Positive matrix factorization (PMF was applied to the high resolution organic aerosol mass spectra obtained by an Aerodyne High Resolution Aerosol Mass Spectrometer (HR-AMS. For Patras five OA sources could be identified: 19% very oxygenated OA (V-OOA, 38% moderately oxygenated OA (M-OOA, 21% biogenic oxygenated OA (b-OOA, 7% hydrocarbon-like OA (HOA-1 associated with traffic sources and 15% hydrocarbon-like OA (HOA-2 related to other primary emissions (including cooking OA. For Athens the corresponding source contributions were: V-OOA (35%, M-OOA (30%, HOA-1 (18% and HOA-2 (17%. In both cities the major component was OOA, suggesting that under high photochemical conditions most of the OA in the Eastern Mediterranean is quite aged. The contribution of the primary sources (HOA-1 and HOA-2 was important (22% in Patras and 33% in Athens but not dominant.

  10. Surface characterization of III-V MOCVD films from heterocyclic single-source precursors; Oberflaechencharakterisierung von III-V MOCVD-Filmen aus heterozyklischen Single Source Precursoren

    Energy Technology Data Exchange (ETDEWEB)

    Seemayer, Andreas

    2009-07-13

    In the present thesis the sublimation and evaporation properties of heterocyclic gallium and antimony containing single-source precursors as well as the chemical composition and morphology of the films fabricated from this were studied. The single-source precursors available by a new synthesis route were characterized concerning their evaporation properties and the obtained films studied surface-physically. By this way the process parameters were optimized and the applicability of the single-source precursors in HV-MOCVD processes studied. By evaporation experiments in the UHV it could be shown that thereby lighter ligands like ethyl- and methyl-groups lead to a lower contamination of the reaction space with carbon containing molecules. Furthermore it was expected that the 6-rings synthetized with short ligands exhibit a high stability. This however could not be confirmed. By unwanted parasitary reactions in the gaseous phase respectively dissociative sublimation in the gaseous phase a deposition of GaSb with these precursors was not possible. The 4-ring stabilized with tertiary-butyl and ethyl-groups caused in the evaporation the largest contamination of the gaseous phase, becauselonger-chain hydrocarbons exhibil only a bad pump cross section. By parasitary reactions originating elementary antimony is detectable in the gaseous phase. The films were studied concerning their chemical composition and their transport- respectively storage-conditioned surface contamination. Furthermore it has become clear that not only a purely synthetized precursor substance but also the reactor design is deciding for a successful deposition and a high film quality. First by successive optimization of the evaporation geometry it was possible to reduce the roughness of the produced GaSb films down to about 10 nm-30 nm.

  11. Development and Identification of Novel Rice Blast Resistant Sources and Their Characterization Using Molecular Markers

    Institute of Scientific and Technical Information of China (English)

    S J S RAMA DEVI; M. S. MADHAV; Kuldeep SINGH; B UMAKANTH; B VISHALAKSHI; P RENUKA; K. VIJAY SUDHAKAR; M. S. PRASAD3; B. C. VIRAKTAMATH; V. RAVINDRA BABU

    2015-01-01

    To develop and characterize introgression lines for leaf and neck blast resistance, 326 introgression lines were developed using various accessions of six different AA genome wild species in the genetic background of elite Indian varieties like PR114 and Pusa 44 and were screened for blast resistance. Stringent phenotyping coupled with genotyping using gene based markers led to the identification of four resistant introgression lines, which showed promising resistance and do not possess any of the tested genes. Furthermore, multi-location screening confirmed the field resistance of the four introgression lines to both leaf and neck blast. Molecular characterization of these introgression lines using genome-wide simple sequence repeat markers revealed the presence of small percentage of wildOryza genome introgrssion. So these lines can be used for mapping and identification of novel leaf and neck blast resistance genes. Thus, these four introgression lines can be considered as new genetic resources for blast resistance.

  12. New developments in CSEM (Controlled Source EM) for reservoir characterization and monitoring

    OpenAIRE

    Wawrzyniak, Pierre; Bourgeois, Bernard; Girard, Jean-François; Bretaudeau, François; Coppo, Nicolas

    2015-01-01

    International audience The use of CSEM onshore monitoring for CO2 plume migration characterization completes the information brought by seismic methods (localisation of saturation fronts): it is sensitive to the positive resistivity variations in the aquifer induced by supercritical C02 injection. Once a baseline 3D seismic survey is done and the structural seismic horizons are known, CSEM monitoring could compete with seismic monitoring because of its really low cost and its ease of imple...

  13. Public Directory Data Sources Do Not Accurately Characterize the Food Environment in Two Predominantly Rural States

    OpenAIRE

    Meghan R. Longacre; Primack, Brian A.; Owens, Peter M; Gibson, Lucinda; Beauregard, Sandy; Mackenzie, Todd A.; Dalton, Madeline A

    2011-01-01

    Communities are being encouraged to develop locally-based interventions to address environmental risk factors for obesity. Online public directories represent an affordable and easily accessible mechanism for mapping community food environments, but may have limited utility in rural areas. The primary aim of this study was to evaluate the efficacy of public directories versus rigorous onsite field verification to characterize the community food environment in 32 geographically-dispersed towns...

  14. Quantitative characterization of highly efficient correlated photon-pair source using biexciton resonance.

    Science.gov (United States)

    Yamamoto, Yasuo; Oohata, Goro; Mizoguchi, Kohji

    2016-03-21

    A high efficiency method for the generation of correlated photon pairs accompanied by reliable means to characterize the efficiency of that process is needed in the study of entangled states, which have important potential applications in quantum information and quantum communication. In this study, we report the first characterization of the efficiency of generation of correlated photon pairs emitted from a CuCl single crystal using the biexciton-resonance hyper-parametric scattering (RHPS) method which is the highly efficient method of generation of correlated photon pairs. In order to characterize the generation efficiency and signal-to-noise ratio of correlated photon pairs using this method, we investigated the pump power dependence on the photon counting rate and coincidence counting rate under resonant excitation. The pump power dependence shows that the power characteristic of the photon counting rates changes from linear to quadratic dependence of the pump power. This behavior represents a superposition of contributions from correlated photon pairs and non-correlated photons. The analysis of the pump power dependence shows that one photon-pair is produced by a pump pulse with 2 x 106 photons. Moreover, the generation efficiency of this method obtained by calculating the number of generated photon pairs per pump power is comparable to that of several methods based on the χ(3) parametric process. PMID:27136797

  15. Characterizing the radiation response of Cherenkov glass detectors with isotopic sources

    Energy Technology Data Exchange (ETDEWEB)

    Hayward, J P [University of Tennessee, Knoxville (UTK); Hobbs, C. L. [University of Tennessee, Knoxville (UTK); Bell, Zane W [ORNL; Boatner, Lynn A [ORNL; Johnson, Rose E [ORNL; Ramey, Joanne Oxendine [ORNL; Jellison Jr, Gerald Earle [ORNL; Lillard, Cole R [ORNL; Ramey, Lucas A [ORNL

    2012-01-01

    Abstract Cherenkov detectors are widely used for particle identification and threshold detectors in high-energy physics. Glass Cherenkov detectors that are sensitive to beta emissions originating from neutron activation have been demonstrated recently as a potential replacement for activation foils. In this work, we set the groundwork to evaluate large Cherenkov glass detectors for sensitivity to MeV photons through first understanding the measured response of small Cherenkov glass detectors to isotopic gamma-ray sources. Counting and pulse height measurements are acquired with reflected glass Cherenkov detectors read out with a photomultiplier tube. Simulation was used to inform our understanding of the measured results. This simulation included radioactive source decay, radiation interaction, Cherenkov light generation, optical ray tracing, and photoelectron production. Implications for the use of Cherenkov glass detectors to measure low energy gammaray response are discussed.

  16. Characterization of an atmospheric pressure air plasma source for polymer surface modification

    Science.gov (United States)

    Yang, Shujun; Tang, Jiansheng

    2013-10-01

    An atmospheric pressure air plasma source was generated through dielectric barrier discharge (DBD). It was used to modify polyethyleneterephthalate (PET) surfaces with very high throughput. An equivalent circuit model was used to calculate the peak average electron density. The emission spectrum from the plasma was taken and the main peaks in the spectrum were identified. The ozone density in the down plasma region was estimated by Absorption Spectroscopy. NSF and ARC-ODU

  17. Source term characterization for the radioactive contamination of a river - reservoir system

    International Nuclear Information System (INIS)

    The source term for radioactive contamination of the Doamnei-Arges river - reservoir system is more than 90% composed by 58 Co and 60 Co from TRIGA reactors cooling system. Measurable amounts of 137 Cs from Chernobyl accident fallout (1986) is coming into the system from atmosphere (resuspension) and from the catchment area (soil erosion). In this paper, a quantitative analysis of the three contamination pathways is performed. (authors)

  18. Characterization of size distributions of elemental mass concentrations in atmospheric aerosols derived from different sources

    International Nuclear Information System (INIS)

    The atmospheric aerosol samples were collected at six representative sites with an 8-stage cascade impactor sampler and analyzed for their elemental mass concentrations by the PIXE analytic method. Based on some indicator elements, the characteristic of size distributions of particles from different sources were obtained. According to these characteristics, we inferred the origins of the ultrafine particles around the Great Wall Station in the Antarctic. (orig.)

  19. Experimental characterization and Monte Carlo simulation of Si(Li) detector efficiency by radioactive sources and PIXE

    Energy Technology Data Exchange (ETDEWEB)

    Mesradi, M. [Institut Pluridisciplinaire Hubert-Curien, UMR 7178 CNRS/IN2P3 et Universite Louis Pasteur, 23 rue du Loess, BP 28, F-67037 Strasbourg Cedex 2 (France); Elanique, A. [Departement de Physique, FS/BP 8106, Universite Ibn Zohr, Agadir, Maroc (Morocco); Nourreddine, A. [Institut Pluridisciplinaire Hubert-Curien, UMR 7178 CNRS/IN2P3 et Universite Louis Pasteur, 23 rue du Loess, BP 28, F-67037 Strasbourg Cedex 2 (France)], E-mail: abdelmjid.nourreddine@ires.in2p3.fr; Pape, A.; Raiser, D.; Sellam, A. [Institut Pluridisciplinaire Hubert-Curien, UMR 7178 CNRS/IN2P3 et Universite Louis Pasteur, 23 rue du Loess, BP 28, F-67037 Strasbourg Cedex 2 (France)

    2008-06-15

    This work relates to the study and characterization of the response function of an X-ray spectrometry system. The intrinsic efficiency of a Si(Li) detector has been simulated with the Monte Carlo codes MCNP and GEANT4 in the photon energy range of 2.6-59.5 keV. After finding it necessary to take a radiograph of the detector inside its cryostat to learn the correct dimensions, agreement within 10% between the simulations and experimental measurements with several point-like sources and PIXE results was obtained.

  20. Synthesis and characterization of zeolite NaP using kaolin waste as a source of silicon and aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrando, Edemarino Araujo, E-mail: edemarino@ufpa.br [Universidae Federal do Para (UFPA), Maraba, PA (Brazil). Fac. de Engenharia de Materias. Lab. de Materiais Ceramicos; Andrade, Christiano Gianesi Bastos; Valenzuela-Diaz, Francisco Rolando [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Dept. de Metalurgia e Engenharia de Materiais; Rocha Junior, Carlos Augusto Ferreira da; Neves, Roberto de Freitas [Universidae Federal do Para (UFPA), Maraba, PA (Brazil). Int. de Tecnologia. Fac. de Engenharia Quimica; Angelica, Romulo Simoes [Universidae Federal do Para (UFPA), Maraba, PA (Brazil). Inst. de Geociencias. Fac. de Geologia

    2014-08-15

    The synthesis of zeolite NaP using kaolin waste, from the Amazon region, as a predominant source of silicon and aluminum has been studied. The zeolitisation process occurred in hydrothermal conditions using static autoclaving and the effects of time, temperature, and the Si/Al ratio were investigated. The starting material and the phases formed as reaction products were characterized by XRD, SEM and FTIR. The results showed that pure zeolite NaP is hydrothermally synthesized, at 100 °C for 20 hours, using meta kaolin waste material in alkaline medium in presence of additional silica. The XRD and SEM analyses indicate that the synthesized zeolite presents good crystallinity. (author)

  1. Geochemistry and mineralogy approaches to characterize brick and its lake sediments sources: Antioch Roman City (Southern Turkey)

    OpenAIRE

    El Ouahabi, Meriam; Hubert, Aurelia; Benjelloun, Yacine; Chene, Grégoire; Strivay, David; De Sigoyer, Julia; Pamir, Hatice; Karabacak, Volkan; Fagel, Nathalie

    2016-01-01

    The Roman aqueduct of Antioch-on-the-Orontes (Southern Turkey) is situated close to the Antioch city. This last is located near the Amik Lake (Lake of Antioch) and close to the junction between the active Dead Sea fault and the East Anatolian fault. During the Roman period, the Amik Plain was more densely occupied than at any time in its history [1]. The study focuses on the bricks and the lake sediments characterization in order to determine the source area as well as the technical productio...

  2. Synthesis and characterization of zeolite NaP using kaolin waste as a source of silicon and aluminum

    International Nuclear Information System (INIS)

    The synthesis of zeolite NaP using kaolin waste, from the Amazon region, as a predominant source of silicon and aluminum has been studied. The zeolitisation process occurred in hydrothermal conditions using static autoclaving and the effects of time, temperature, and the Si/Al ratio were investigated. The starting material and the phases formed as reaction products were characterized by XRD, SEM and FTIR. The results showed that pure zeolite NaP is hydrothermally synthesized, at 100 °C for 20 hours, using meta kaolin waste material in alkaline medium in presence of additional silica. The XRD and SEM analyses indicate that the synthesized zeolite presents good crystallinity. (author)

  3. Monte Carlo characterization of the Gamma-Med Hdr plus Ir-192 brachytherapy source

    Energy Technology Data Exchange (ETDEWEB)

    Reyes, E.; Sosa, M. A.; Gil V, A. [Universidad de Guanajuato, Division de Ciencias e Ingenierias, Av. Insurgentes 2354, 37150 Leon, Guanajuato (Mexico); Monzon, E., E-mail: eric_1985@fisica.ugto.mx [IMSS, Unidad Medica de Alta Especialidad No. 1, Av. Adolfo Lopez Mateos 1813, 37340 Leon, Guanajuato (Mexico)

    2015-10-15

    Full text: The MCNP4C Monte Carlo code was used to simulate the dosimetry around the Gamma-Med Hdr Plus iridium-192 brachytherapy source in both air/vacuum and water environments. Dosimetry data in water was calculated and are presented into an away-along table. All dosimetric quantities recommended by the AAPM Task Group 43 report have been also calculated. These quantities are air kerma strength, dose rate constant, radial dose function and anisotropy function. The obtained data are compared to this source reference data, finding results in good agreement with them. In this study, recommendations of the AAPM TG-43U1 report have been followed and comply with the most recent AAPM and ESTRO physics committee recommendations about Monte Carlo techniques. The data in the present study complement published data and can be used as input in the Tps or as benchmark data to verify the results of the treatment planning systems as well as a means of comparison with other datasets from this source. (Author)

  4. Polybrominated diphenyl ethers in farmland soils: source characterization, deposition contribution and apportionment.

    Science.gov (United States)

    Dong, Yian; Li, Li; Bie, Pengju; Jia, Shenglan; Wang, Qiang; Huang, Zhi; Qiu, Xinghua; Zhang, Jianbo; Hu, Jianxin

    2014-01-01

    Polybrominated diphenyl ethers (PBDEs), a group of persistent organic pollutants (POPs), are caused for concern recently due to their adverse health effects and environmental ubiquity. In this study, atmospheric and soil PBDE levels in Taizhou, one of the largest WEEE dismantling areas in the world, were measured, ranging from 884 to 2791 pg m(-3) with an average of 1968 pg m(-3) for atmosphere and 2.96 to 200 ng g(-1)dry weight (dw) with the mean of 65.2 ng g(-1)dw for farmland soils, respectively. The close connection between soil PBDE accumulation and atmospheric deposition was also revealed by the estimation of the annual PBDE deposition flux (3.1 ± 0.9 mg m(-2)a(-1)) and the similarity between deposited congener pattern and soil congener profile. Positive matrix factorization (PMF) was conducted to extract possible sources of farmland soil PBDEs and to calculate their contributions. Based on the measured source profiles of PBDE-related activities, five sources were identified representing WEEE dumping, WEEE dismantling, WEEE open burning, residential waste dismantling, and residential waste open burning. WEEE-related recycling activities contributed primary percentage (52%) to farmland soil PBDE concentration, and open burning was an important pathway for PBDEs entering the environment.

  5. Characterization of an ion beam produced by extraction and acceleration of ions from a wire plasma source

    International Nuclear Information System (INIS)

    In this study we first model a DC low pressure wire plasma source and then characterize the properties of an ion gun derived from the plasma source. In order to study the properties of the derived ion gun, we develop a particle-in-cell code fitted to the modelling of the wire plasma source operation, and validate it by confrontation with the results of an experimental study. In light of the simulation results, an analysis of the wire discharge in terms of a collisional Child-Langmuir ion flow in cylindrical geometry is proposed. We interpret the mode transition as a natural reorganization of the discharge when the current is increased above a threshold value which is a function of the discharge voltage, the pressure and the inter-electrodes distance. In addition, the analysis of the energy distribution function of ions impacting the cathode demonstrates the ability to extract an ion beam of low energy spread around the discharge voltage assuming that the discharge is operated in its high pressure mode. An ion source prototype allowing the extraction and acceleration of ions from the wire source is then proposed. The experimental study of such a device confirms that, apart from a shift corresponding to the accelerating voltage, the acceleration scheme does not spread the ion velocity distribution function along the axis of the beam. It is therefore possible to produce tunable energy (0 - 5 keV) ion beams of various ionic species presenting limited energy dispersion ( 10 eV). The typical beam currents are about a few tens of micro-amperes, and the divergence of such a beam is on the order of one degree. A numerical modelling of the ion source is eventually conducted in order to identify potential optimizations of the concept. (author)

  6. Characterization and packaging of disused sealed radioactive sources; Caracterizacion y acondicionamiento de fuentes radiactivas selladas en desuso

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar, S.L. [Instituto Boliviano de Ciencia y Tecnologia Nuclear (IBTEN), La Paz (Bolivia, Plurinational State of)

    2013-07-01

    In Bolivia are generated disused sealed sources and radioactive waste resulting from the use of radioactive materials in industrial, research and medicine. The last includes the diagnosis and treatment. Whereas exposure to ionizing radiation is a potential hazard to personnel who applies it, to those who benefit from its use or for the community at large, it is necessary to control the activities in this field. The Instituto Boliviano de Ciencia y Tecnologia Nuclear - IBTEN is working on a regional project from International Atomic Energy Agency - IAEA, RLA/09/062 Project - TSA 4, Strengthening the National Infrastructure and Regulatory Framework for the Safe Management of Radioactive waste in Latin America. This Project has strengthened the regulatory framework regarding the safe management of radioactive waste. The aim of this work was focused primarily on the security aspects in the safe management of disused sealed sources. The tasks are listed below: 1. Characterization of disused sealed sources 2. Preparation for transport to temporary storage 3. Control of all disused radioactive sources. (author)

  7. Characterization and source identification of organic matter in view of land uses and heavy rainfall in the Lake Shihwa, Korea

    International Nuclear Information System (INIS)

    Highlights: • Organic matter derived from industrial area showed high biodegradability. • Organic matter transported from rural area was of refractory nature. • Autochthonous organic matter dominated in lake during the dry season. • Contributions of organic source by industrial and rural area increased at rainy season. - Abstract: The characteristics and sources of organic matter in water of the Lake Shihwa, which receives inputs from rural, urban, and industrial areas, were evaluated by examining the biodegradable organic carbon concentration, fluorescence spectra, and carbon and nitrogen isotope ratios, especially during rainy season and dry season. The organic matter transported from rural areas was of refractory nature, while that of industrial origin decomposed rapidly. As compared to the dry season, the organic matter in the rainy season was characterized by a reduced labile fraction. During the dry season, the autochthonous organic matter dominated in the lake, however, the contributions of allochthonous organic sources by industrial and rural areas significantly increased at rainy season. This investigation revealed that the transport of organic matter of anthropogenic origin to the Lake Shihwa was mainly influenced by heavy rainfall. Moreover, each anthropogenic source could differently influence the occurrence of organic matter in water of the Lake Shihwa

  8. Characterization of PM10 chemical composition and its variability in relation to different sources in the central Mediterranean

    Science.gov (United States)

    Calzolai, Giulia; Nava, Silvia; Chiari, Massimo; Lucarelli, Franco; Becagli, Silvia; Traversi, Rita; Marconi, Miriam; Rugi, Francesco; Udisti, Roberto; di Sarra, Alcide; Pace, Giovanni; Meloni, Daniela; Bommarito, Carlo; Sferlazzo, Damiano

    2013-04-01

    Atmospheric aerosols are estimated to play a relevant role in climate change, also in relation to global warming and to the hydrological cycle; information on aerosol sources and impact are among the data needed to constrain uncertainties in climate change models. This is particularly important in the Mediterranean basin, whose atmosphere is heavily polluted and characterized by strong influences from both natural and anthropogenic emissions. An investigation aimed at assessing the aerosol sources affecting the Central Mediterranean basin has been carried out by applying the Positive Matrix Factorization (PMF) model to a 2-year long data set of PM10 mass concentration and chemical composition of samples collected on the island of Lampedusa (35.5° N, 12.6° E, 45 m a.s.l.). Lampedusa is an ideal site for this kind of studies, as it is far from continental pollution sources (the nearest coast, in Tunisia, is more than 100 km away). Samples were collected on a daily basis; after mass gravimetric measurements, different portions of the samples were analyzed for the ionic content by Ion Cromatography (IC), for soluble metals by Inductively Coupled Plasma Atomic Emission Spectrometer (ICP-AES), and for the total (soluble + insoluble) elemental composition by Particle Induced X-ray Emission (PIXE). Data from years 2007 and 2008 are used in this study. Seven sources were resolved: sea-salt, mineral dust, biogenic emissions, primary ship emissions, secondary sulphate, secondary nitrate, and biomass burning emissions. The chemical profiles of each source were identified and compared with literature data; the temporal evolution of each source was studied, in relation to seasonal changes and influence of different source regions. Air mass backward trajectories were also used in the analysis. Daily absolute and relative contributions of the aerosol produced by each of the seven resolved sources to the PM10 in Lampedusa were also obtained. On average, each of the sources

  9. Characterization of Calcium Compounds in Opuntia ficus indica as a Source of Calcium for Human Diet

    OpenAIRE

    Isela Rojas-Molina; Elsa Gutiérrez-Cortez; Moustapha Bah; Alejandra Rojas-Molina; César Ibarra-Alvarado; Eric Rivera-Muñoz; Alicia del Real; Ma. de los Angeles Aguilera-Barreiro

    2015-01-01

    Analyses of calcium compounds in cladodes, soluble dietary fiber (SDF), and insoluble dietary fiber (IDF) of Opuntia ficus indica are reported. The characterization of calcium compounds was performed by using Scanning Electron Microscopy, Energy Dispersive Spectrometry, X-ray diffraction, and infrared spectroscopy. Atomic Absorption Spectroscopy and titrimetric methods were used for quantification of total calcium and calcium compounds. Whewellite (CaC2O4·H2O), weddellite (CaC2O4·(H2O)2.375),...

  10. Volatile organic compounds over Eastern Himalaya, India: temporal variation and source characterization using Positive Matrix Factorization

    OpenAIRE

    Sarkar, C.; Chatterjee, A.; D. Majumdar; S. K. Ghosh; Srivastava, A.; Raha, S.

    2014-01-01

    A first ever study on the characterization of volatile organic compounds (VOCs) has been made over a Himalayan high altitude station in India. A total of 18 VOCs (mono aromatics-BTEX (benzene, toluene, ethylbenzene, xylene), non-BTEX substituted aromatics and halocarbon) have been measured over Darjeeling (27.01° N, 88.15° E, 2200 m a.s.l.) in the eastern Himalaya in India during the period of July 2011–June 2012. The annual average concentration of the sum of 18 tar...

  11. Anthropogenic Methane Emissions in California's San Joaquin Valley: Characterizing Large Point Source Emitters

    Science.gov (United States)

    Hopkins, F. M.; Duren, R. M.; Miller, C. E.; Aubrey, A. D.; Falk, M.; Holland, L.; Hook, S. J.; Hulley, G. C.; Johnson, W. R.; Kuai, L.; Kuwayama, T.; Lin, J. C.; Thorpe, A. K.; Worden, J. R.; Lauvaux, T.; Jeong, S.; Fischer, M. L.

    2015-12-01

    Methane is an important atmospheric pollutant that contributes to global warming and tropospheric ozone production. Methane mitigation could reduce near term climate change and improve air quality, but is hindered by a lack of knowledge of anthropogenic methane sources. Recent work has shown that methane emissions are not evenly distributed in space, or across emission sources, suggesting that a large fraction of anthropogenic methane comes from a few "super-emitters." We studied the distribution of super-emitters in California's southern San Joaquin Valley, where elevated levels of atmospheric CH4 have also been observed from space. Here, we define super-emitters as methane plumes that could be reliably detected (i.e., plume observed more than once in the same location) under varying wind conditions by airborne thermal infrared remote sensing. The detection limit for this technique was determined to be 4.5 kg CH4 h-1 by a controlled release experiment, corresponding to column methane enhancement at the point of emissions greater than 20% above local background levels. We surveyed a major oil production field, and an area with a high concentration of large dairies using a variety of airborne and ground-based measurements. Repeated airborne surveys (n=4) with the Hyperspectral Thermal Emission Spectrometer revealed 28 persistent methane plumes emanating from oil field infrastructure, including tanks, wells, and processing facilities. The likelihood that a given source type was a super-emitter varied from roughly 1/3 for processing facilities to 1/3000 for oil wells. 11 persistent plumes were detected in the dairy area, and all were associated with wet manure management. The majority (11/14) of manure lagoons in the study area were super-emitters. Comparing to a California methane emissions inventory for the surveyed areas, we estimate that super-emitters comprise a minimum of 9% of inventoried dairy emissions, and 13% of inventoried oil emissions in this region.

  12. Using stable isotopes to characterize groundwater recharge sources in the volcanic island of Madeira, Portugal

    Science.gov (United States)

    Prada, Susana; Cruz, J. Virgílio; Figueira, Celso

    2016-05-01

    The hydrogeology of volcanic islands remains poorly understood, despite the fact that populations that live on them rely on groundwater as a primary water source. This situation is exacerbated by their complex structure, geological heterogeneity, and sometimes active volcanic processes that hamper easy analysis of their hydrogeological dynamics. Stable isotope analysis is a powerful tool that has been used to assess groundwater dynamics in complex terrains. In this work, stable isotopes are used to better understand the hydrogeology of Madeira Island and provide a case-study that can serve as a basis for groundwater studies in other similar settings. The stable isotopic composition (δ18O and δ2H) of rain at the main recharge areas of the island is determined, as well as the sources and altitudes of recharge of several springs, groundwater in tunnels and wells. The water in tunnels was found to be recharged almost exclusively by rain in the deforested high plateaus, whilst several springs associated with shallow perched aquifers are recharged from rain and cloud water interception by the vegetated slopes. Nevertheless some springs thought to be sourced from deep perched aquifers, recharge in the central plateaus, and their isotopic composition is similar to the water in the tunnels. Recharge occurs primarily during autumn and winter, as evidenced by the springs and tunnels Water Lines (WL). The groundwater in wells appears to originate from runoff from rain that falls along the slopes that infiltrates near the streams' mouths, where the wells are located. This is evident by the evaporation line along which the wells plot. Irrigation water is also a possible source of recharge. The data is compatible with the hydrogeological conceptual model of Madeira. This work also shows the importance of cloud water interception as a net contributor to groundwater recharge, at least in the perched aquifers that feed numerous springs. As the amount of rainfall is expected to

  13. Using temporal distributions of transient events to characterize cosmological source populations

    CERN Document Server

    Howell, E; Burman, R; Blair, D

    2010-01-01

    The brightest events in a time series of cosmological transients obey an observation time dependence which is often overlooked. This dependence can be exploited to probe the global properties of electromagnetic and gravitational wave transients (Howell et al. 2007a, Coward & Burman 2005). We describe a new relation based on a peak flux--observation time distribution and show that it is invariant to the luminosity distribution of the sources (Howell et al. 2007b). Applying this relation, in combination with a new data analysis filter, to \\emph{Swift} gamma-ray burst data, we demonstrate that it can constrain their rate density.

  14. Physiological and genetic characterization of plant growth and gravitropism in LED light sources

    Science.gov (United States)

    Deitzer, Gerald F.

    1994-01-01

    Among the many problems of growing plants in completely controlled environments, such as those anticipated for the space station and the CELSS program, is the need to provide light that is both adequate for photosynthesis and of proper quality for normal growth and development. NASA scientists and engineers have recently become interested in the possibility of utilizing densely packed, solid state, light emitting diodes (LED's) as a source for this light. Unlike more conventional incandescent or electrical discharge lamps, these sources are highly monochromatic and lack energy in spectral regions thought to be important for normal plant development. In addition, a recent observation by NASA scientist has suggested that infra-red LED's, that are routinely used as photographic safelights for plants grown in darkness, may interact with the ability of plants to detect gravity. In order to establish how plants respond to light from these LED light sources we carried out a series of experiments with known pigment mutants of the model mustard plant, Arabidopsis thaliana, growing in either a gravity field or on a clinostat to simulate a micro-gravity environment. Results indicate that only red light from the 665 nm LED's disrupts the ability of normal wildtype seedlings to detect a gravity stimulus. There was no consistent effect found for the far-red (735 nm) LED's or either of the infrared (880 nm or 935 nm) LED sources but both showed some effect in one or more of the genotypes tested. Of these five members of the phytochrome multigene family in Arabidopsis, only the phytochrome B pigment mutant (hy3) lacked the ability to detect gravity under all conditions. There was no effect of either micro-gravity (clinostat) or the infra-red LED's on the light induced inhibition of hypocotyl elongation. Measurements of the pigment phytochrome in oats also showed no photoconversion by 15 min irradiations with the infra-red LED's. We conclude that phytochrome B is required for the

  15. Development of a chip-based ingroove microplasma source: Design, characterization, and diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xuemei; Meng, Fanying; Yuan, Xin; Yan, Yanyue; Zhao, Zhongjun; Duan, Yixiang, E-mail: yduan@scu.edu.cn [Research Center of Analytical Instrumentation, College of Chemistry and College of Life Science Sichuan University, Chengdu (China); Tang, Jie [State Key Laboratory of Transient Optics and Photonics, Xi' an Institute of Optics and Precision Mechanics of CAS, Xi' an (China)

    2014-03-10

    A chip-based ingroove microplasma source was designed for molecular emission spectrometry by using a space-confined direct current duct in air. The voltage-current characteristics of different size generators, emission spectroscopy of argon were discussed, respectively. It is found that the emission intensity of excited Ar and N{sub 2} approaches its maximum near the cathode, while OH and O peaks most likely appear close to the anode. The electron density, electronic excitation temperature, rotational temperature, and vibrational temperature of the argon plasma were also calculated. More importantly, the chip-based ingroove microplasma shows much better stability compared with its counterparts.

  16. Characterization and source apportionment of particulate matter Indonesia, during a recent peat fire episode.

    Science.gov (United States)

    See, Siao Wei; Balasubramanian, Rajasekhar; Rianawati, Elisabeth; Karthikeyan, Sathrugnan; Streets, David G

    2007-05-15

    An intensive field study was conducted in Sumatra, Indonesia, during a peat fire episode to investigate the physical and chemical characteristics of particulate emissions in peat smoke and to provide necessary data for source-receptor analyses. Ambient air sampling was carried out at three different sites located at varying distances from the peatfires to determine changes in mass and number concentrations of PM2.5 and its chemical composition (carbonaceous and nitrogenous materials, polycyclic aromatic hydrocarbons, water-soluble inorganic and organic ions, and total and water-soluble metals). The three sites represent a rural site directly affected by the local peat combustion, a semirural site, and an urban site situated downwind of the peat fires. The mass concentration of PM2.5 and the number concentration of airborne particles were as high as 1600 microg/m3 and 1.7 x 10(5) cm(-3), respectively, in the vicinity of peat fires. The major components of PM2.5 in peat smoke haze were carbonaceous particles, particularly organic carbon, NO3-, and SO4(2-), while the less abundant constituents included ions such as NH4+, NO2-, Na+, K+, organic acids, and metals such as Al, Fe, and Ti. Source apportionment by chemical mass balance receptor modeling indicates that peat smoke can travel long distances and significantly affect the air quality at locations downwind.

  17. Hydrochemical characterization and pollution sources identification of groundwater in Salawusu aquifer system of Ordos Basin, China.

    Science.gov (United States)

    Yang, Qingchun; Wang, Luchen; Ma, Hongyun; Yu, Kun; Martín, Jordi Delgado

    2016-09-01

    Ordos Basin is located in an arid and semi-arid region of northwestern China, which is the most important energy source bases in China. Salawusu Formation (Q3 s) is one of the most important aquifer systems of Ordos Basin, which is adjacent to Jurassic coalfield areas. A large-scale exploitation of Jurassic coal resources over ten years results in series of influences to the coal minerals, such as exposed to the oxidation process and dissolution into the groundwater due to the precipitation infiltration. Therefore, how these processes impact groundwater quality is of great concerns. In this paper, the descriptive statistical method, Piper trilinear diagram, ratios of major ions and canonical correspondence analysis are employed to investigate the hydrochemical evolution, determine the possible sources of pollution processes, and assess the controls on groundwater compositions using the monitored data in 2004 and 2014 (before and after large-scale coal mining). Results showed that long-term exploration of coal resources do not result in serious groundwater pollution. The hydrochemical types changed from HCO3(-)-CO3(2-) facies to SO4(2-)-Cl facies during 10 years. Groundwater hardness, nitrate and sulfate pollution were identified in 2014, which was most likely caused by agricultural activities. PMID:27294785

  18. Rapid Source Characterization of the 2011 Mw 9.0 off the Pacific coast of Tohoku Earthquake

    Science.gov (United States)

    Hayes, Gavin P.

    2011-01-01

    On March 11th, 2011, a moment magnitude 9.0 earthquake struck off the coast of northeast Honshu, Japan, generating what may well turn out to be the most costly natural disaster ever. In the hours following the event, the U.S. Geological Survey National Earthquake Information Center led a rapid response to characterize the earthquake in terms of its location, size, faulting source, shaking and slip distributions, and population exposure, in order to place the disaster in a framework necessary for timely humanitarian response. As part of this effort, fast finite-fault inversions using globally distributed body- and surface-wave data were used to estimate the slip distribution of the earthquake rupture. Models generated within 7 hours of the earthquake origin time indicated that the event ruptured a fault up to 300 km long, roughly centered on the earthquake hypocenter, and involved peak slips of 20 m or more. Updates since this preliminary solution improve the details of this inversion solution and thus our understanding of the rupture process. However, significant observations such as the up-dip nature of rupture propagation and the along-strike length of faulting did not significantly change, demonstrating the usefulness of rapid source characterization for understanding the first order characteristics of major earthquakes.

  19. Characterization and authentication of a novel vegetable source of omega-3 fatty acids, sacha inchi (Plukenetia volubilis L.) oil.

    Science.gov (United States)

    Maurer, Natalie E; Hatta-Sakoda, Beatriz; Pascual-Chagman, Gloria; Rodriguez-Saona, Luis E

    2012-09-15

    Consumption of omega-3 fatty acids (ω-3's), whether from fish oils, flax or supplements, can protect against cardiovascular disease. Finding plant-based sources of the essential ω-3's could provide a sustainable, renewable and inexpensive source of ω-3's, compared to fish oils. Our objective was to develop a rapid test to characterize and detect adulteration in sacha inchi oils, a Peruvian seed containing higher levels of ω-3's in comparison to other oleaginous seeds. A temperature-controlled ZnSe ATR mid-infrared benchtop and diamond ATR mid-infrared portable handheld spectrometers were used to characterize sacha inchi oil and evaluate its oxidative stability compared to commercial oils. A soft independent model of class analogy (SIMCA) and partial least squares regression (PLSR) analyzed the spectral data. Fatty acid profiles showed that sacha inchi oil (44% linolenic acid) had levels of PUFA similar to those of flax oils. PLSR showed good correlation coefficients (R(2)>0.9) between reference tests and spectra from infrared devices, allowing for rapid determination of fatty acid composition and prediction of oxidative stability. Oils formed distinct clusters, allowing the evaluation of commercial sacha inchi oils from Peruvian markets and showed some prevalence of adulteration. Determining oil adulteration and quality parameters, by using the ATR-MIR portable handheld spectrometer, allowed for portability and ease-of-use, making it a great alternative to traditional testing methods.

  20. Characterization and authentication of a novel vegetable source of omega-3 fatty acids, sacha inchi (Plukenetia volubilis L.) oil.

    Science.gov (United States)

    Maurer, Natalie E; Hatta-Sakoda, Beatriz; Pascual-Chagman, Gloria; Rodriguez-Saona, Luis E

    2012-09-15

    Consumption of omega-3 fatty acids (ω-3's), whether from fish oils, flax or supplements, can protect against cardiovascular disease. Finding plant-based sources of the essential ω-3's could provide a sustainable, renewable and inexpensive source of ω-3's, compared to fish oils. Our objective was to develop a rapid test to characterize and detect adulteration in sacha inchi oils, a Peruvian seed containing higher levels of ω-3's in comparison to other oleaginous seeds. A temperature-controlled ZnSe ATR mid-infrared benchtop and diamond ATR mid-infrared portable handheld spectrometers were used to characterize sacha inchi oil and evaluate its oxidative stability compared to commercial oils. A soft independent model of class analogy (SIMCA) and partial least squares regression (PLSR) analyzed the spectral data. Fatty acid profiles showed that sacha inchi oil (44% linolenic acid) had levels of PUFA similar to those of flax oils. PLSR showed good correlation coefficients (R(2)>0.9) between reference tests and spectra from infrared devices, allowing for rapid determination of fatty acid composition and prediction of oxidative stability. Oils formed distinct clusters, allowing the evaluation of commercial sacha inchi oils from Peruvian markets and showed some prevalence of adulteration. Determining oil adulteration and quality parameters, by using the ATR-MIR portable handheld spectrometer, allowed for portability and ease-of-use, making it a great alternative to traditional testing methods. PMID:23107745

  1. In-situ characterization of wastewater flow and transport from at-grade line sources to shallow groundwater

    Science.gov (United States)

    Weldeyohannes, A. O.; Kachanoski, R. G.; Dyck, M. F.

    2011-12-01

    A better understanding of multidimensional unsaturated and saturated flow and transport under boundary conditions typical of on-site wastewater disposal systems is required to assess the risk to groundwater contamination. The main objective of this research is to characterize in-situ wastewater flow and transport from at-grade line sources on a shallow groundwater conditions. The research site was conducted at Wetaskiwin Rest Stop, Alberta, Canada, where ultraviolet disinfected wastewater has been disposed off to the ground via pressurized at-grade line sources since 2007. The site was characterized for wastewater plume and temporal groundwater fluctuation by using Electromagnetic induction (EM31) and (EM38); and by grid of 74 water table wells, 14 piezometers and 11 transducers. Groundwater was analyzed for selected tracers (pH, EC and Cl) and some microbiology (e.g. E. coli). From the results wastewater plume was identified; and wastewater plume center of mass and average flow direction were estimated. Along the horizontal plume center of mass, 30 monitoring wells in 10 nests and 31 temperature sensors in 5 nests were installed to get vertical resolution of the wastewater plume and to track contaminant transport over time. Results, implications and plans for future investigations will be presented. The research output will benefit future research on contaminant fate and transport and groundwater risk assessment plans. Key words: On-site wastewater treatment/disposal system, Wastewater plume, Groundwater contamination.

  2. Characterization and In Vitro Evaluation of Cytotoxicity, Antimicrobial and Antioxidant Activities of Chitosans Extracted from Three Different Marine Sources.

    Science.gov (United States)

    Hajji, Sawssen; Younes, Islem; Rinaudo, Marguerite; Jellouli, Kemel; Nasri, Moncef

    2015-09-01

    Chitins in the α and β isomorphs were extracted from three Tunisian marine sources shrimp (Penaeus kerathurus) waste, crab (Carcinus mediterraneus) shells and cuttlefish (Sepia officinalis) bones. The obtained chitins were transformed into chitosans, the acid-soluble form of chitin. Chitosans were characterized and their biological activities were compared. Chitosan samples were then characterized by Fourier transform infrared spectroscopy (FTIR). The results showed that all chitosans presented identical spectra. Antimicrobial, antioxidant, and antitumor activities of the extracted chitosans were investigated. In fact, cuttlefish chitosan showed the highest DPPH radical-scavenging activity (83 %, 5 mg/ml), whereas it was 79 % and 76 % for shrimp and crab chitosans, respectively. However, in linoleate-β-carotene system, cuttlefish and crab chitosans exerted higher antioxidant activity (82 % and 70 %, respectively), than shrimp chitosan (49 %). Chitosans were tested for their antimicrobial activities against three Gram-negative and four Gram-positive bacteria and five fungi. Chitosans markedly inhibited growth of most bacteria and fungi tested, although the antimicrobial activity depends on the type of microorganism and on the source of chitin. In addition, chitosans showed high antitumor activity which seemed to be dependent on the chitosan characteristics such as acetylation degree and especially the molecular weight.

  3. Rockfall source characterization at high rock walls in complex geological settings by photogrammetry, structural analysis and DFN techniques

    Science.gov (United States)

    Agliardi, Federico; Riva, Federico; Galletti, Laura; Zanchi, Andrea; Crosta, Giovanni B.

    2016-04-01

    Rockfall quantitative risk analysis in areas impended by high, subvertical cliffs remains a challenge, due to the difficult definition of potential rockfall sources, event magnitude scenarios and related probabilities. For this reasons, rockfall analyses traditionally focus on modelling the runout component of rockfall processes, whereas rock-fall source identification, mapping and characterization (block size distribution and susceptibility) are over-simplified in most practical applications, especially when structurally complex rock masses are involved. We integrated field and remote survey and rock mass modelling techniques to characterize rock masses and detect rockfall source in complex geo-structural settings. We focused on a test site located at Valmadrera, near Lecco (Southern Alps, Italy), where cliffs up to 600 m high impend on a narrow strip of Lake Como shore. The massive carbonates forming the cliff (Dolomia Principale Fm), normally characterized by brittle structural associations due to their high strength and stiffness, are here involved in an ENE-trending, S-verging kilometre-scale syncline. Brittle mechanisms associated to folding strongly controlled the nature of discontinuities (bedding slip, strike-slip faults, tensile fractures) and their attributes (spacing and size), as well as the spatial variability of bedding attitude and fracture intensity, with individual block sizes up to 15 m3. We carried out a high-resolution terrestrial photogrammetric survey from distances ranging from 1500 m (11 camera stations from the opposite lake shore, 265 pictures) to 150 m (28 camera stations along N-S directed boat routes, 200 pictures), using RTK GNSS measurements for camera station geo-referencing. Data processing by Structure-from-Motion techniques resulted in detailed long-range (1500 m) and medium-range (150 to 800 m) point clouds covering the entire slope with maximum surface point densities exceeding 50 pts/m2. Point clouds allowed a detailed

  4. Characterization of new sources of derivative starches as wall materials of essential oil by spray drying

    Directory of Open Access Journals (Sweden)

    Iñigo Verdalet-Guzmán

    2013-12-01

    Full Text Available Starch derivatives of taro (Colocasia esculenta L. Schott and rice were characterized as wall materials of orange oil (d-limonene by spray drying. Native starches were initially hydrolyzed with HCl and then esterified. Succinylated starches were modified using a conventional method in a slurry and were extruded; whereas, the phosphorylated starches were modified using the extrusion process. Viscosity and solubility of starches reduced after acid hydrolysis, derivatization, and extrusion. The particle size of the wall materials ranged between 20.05 and 31.81 µm. The encapsulation efficiency of the phosphorylated taro, rice, and waxy corn starches was 96.9, 96.8 and 97.1% respectively, and 98.6, 98.1, and 98.8% for succynilated taro, rice, and waxy corn starches, respectively. Starch derivatives of taro and rice could potentially be used as wall materials of orange oil d-limonene.

  5. Isolation and characterization of microsatellite loci for Bixa orellana, an important source of natural dyes.

    Science.gov (United States)

    Dequigiovanni, G; Ramos, S L F; Zucchi, M I; Bajay, M M; Pinheiro, J B; Fabri, E G; Bressan, E A; Veasey, E A

    2014-01-01

    Annatto (Bixa orellana) is a plant native from the American continental tropical zone. The seeds are used to produce a carotenoid-based yellow to orange food coloring. Microsatellite markers were developed for the Brazilian native species Bixa orellana to describe its genetic diversity and structure as well as to support conservation studies. Twenty-five microsatellite loci were isolated and characterized using an enriched genomic library. Ten loci were polymorphic in the 50 accessions sampled in this study, while 15 were considered monomorphic. The mean number of alleles per locus was 3.8, ranging from 2 to 6 alleles per locus. Mean values for the observed and expected heterozygosities were 0.541 (ranging from 0 to 0.658) and 0.639 (ranging from 0.422 to 0.787), respectively. All markers described in this study will be useful in further studies evaluating the genetic diversity, population dynamics, and conservation genetics of Bixa orellana. PMID:25366801

  6. Characterization of a Be(p,xn) neutron source for fission yields measurements

    CERN Document Server

    Mattera, A; Hjalmarsson, A; Lantz, M; Pomp, S; Rakopoulos, V; Solders, A; Valldor-Blücher, J; Gorelov, D; Penttilä, H; Rinta-Antila, S; Prokofiev, A V; Passoth, E; Bedogni, R; Gentile, A; Bortot, D; Esposito, A; Introini, M V; Pola, A

    2013-01-01

    We report on measurements performed at The Svedberg Laboratory (TSL) to characterize a proton-neutron converter for independent fission yield studies at the IGISOL-JYFLTRAP facility (Jyv\\"askyl\\"a, Finland). A 30 MeV proton beam impinged on a 5 mm water-cooled Beryllium target. Two independent experimental techniques have been used to measure the neutron spectrum: a Time of Flight (TOF) system used to estimate the high-energy contribution, and a Bonner Sphere Spectrometer able to provide precise results from thermal energies up to 20 MeV. An overlap between the energy regions covered by the two systems will permit a cross-check of the results from the different techniques. In this paper, the measurement and analysis techniques will be presented together with some preliminary results.

  7. Characterization of U(VI) reduction in contaminated sediments with slow-degrading electron donor source

    Science.gov (United States)

    Wu, W.; Watson, D. B.; Zhang, G.; Mehlhorn, T.; Lowe, K.; Earles, J.; Phillips, J.; Kelly, S. D.; Boyanov, M.; Kemner, K. M.; Schadt, C.; Criddle, C. S.; Jardine, P. M.; Brooks, S. C.

    2011-12-01

    In order to select sustainable, high efficiency and cost effective electron donor source, oleate and emulsified vegetable oil (EVO) were tested uranium (VI) reduction in comparison with ethanol in microcosms using uranium contaminated sediments and groundwater from the US DOE Oak Ridge Integrated Field Research Challenge (ORIFRC) site. The effect of initial sulfate concentration on U(VI) reduction was also tested. Both oleate and EVO were effective electron donor sources for U(VI) reduction. Accumulation of acetate as a major product and the removal of aqueous U(VI) were observed and were associated with sulfate reduction. Both oleate and EVO supported U(VI) reduction but at slower rates with a comparable but slightly lower extent of reduction than ethanol. X-ray absorption near-edge spectroscopy (XANES) analysis confirmed reduction of U(VI) to U(IV). The extent of U(VI) reduction in solid phase was negatively influenced by aqueous calcium concentration. The majority of electrons of the three substrates were consumed by sulfate reduction, Fe(III) reduction, and methanogenesis. Initial U(VI) concentration in the aqueous phase increased with increased sulfate concentration (1 versus 5 mM), likely due to U(VI) desorption from the solid phase. At the higher initial sulfate concentration more U(VI) was reduced and fewer electrons were used in methanogenesis. Analysis of bacterial and archeal populations using 16S rRNA gene libraries showed a significant increase in Deltaproteobacteria after biostimulation. The microbial community structures developed with oleate and EVO were significantly distinct from those developed with ethanol. Bacteria similar to Desulforegula spp. was predominant for oleate and EVO degradation but were not observed in ethanol-amended microcosms. Known U(VI)-reducing bacteria in the microcosms amended with the three electron donor sources included iron(III) reducing Geobacter spp. but in lower abundances than sulfate-reducing Desulfovibrio spp. The

  8. Preparation and characterization of B4C coatings for advanced research light sources.

    Science.gov (United States)

    Störmer, Michael; Siewert, Frank; Sinn, Harald

    2016-01-01

    X-ray optical elements are required for beam transport at the current and upcoming free-electron lasers and synchrotron sources. An X-ray mirror is a combination of a substrate and a coating. The demand for large mirrors with single layers consisting of light or heavy elements has increased during the last few decades; surface finishing technology is currently able to process mirror lengths up to 1 m with microroughness at the sub-nanometre level. Additionally, thin-film fabrication is able to deposit a suitable single-layer material, such as boron carbide (B4C), some tens of nanometres thick. After deposition, the mirror should provide excellent X-ray optical properties with respect to coating thickness errors, microroughness values and slope errors; thereby enabling the mirror to transport the X-ray beam with high reflectivity, high beam flux and an undistorted wavefront to an experimental station. At the European XFEL, the technical specifications of the future mirrors are extraordinarily challenging. The acceptable shape error of the mirrors is below 2 nm along the whole length of 1 m. At the Helmholtz-Zentrum Geesthacht (HZG), amorphous layers of boron carbide with thicknesses in the range 30-60 nm were fabricated using the HZG sputtering facility, which is able to cover areas up to 1500 mm long by 120 mm wide in one step using rectangular B4C sputtering targets. The available deposition area is suitable for the specified X-ray mirror dimensions of upcoming advanced research light sources such as the European XFEL. The coatings produced were investigated by means of X-ray reflectometry and interference microscopy. The experimental results for the B4C layers are discussed according to thickness uniformity, density, microroughness and thermal stability. The variation of layer thickness in the tangential and sagittal directions was investigated in order to estimate the achieved level of uniformity over the whole deposition area, which is considerably

  9. Characterization of aerosol composition, concentrations, and sources at Baengnyeong Island, Korea using an aerosol mass spectrometer

    Science.gov (United States)

    Lee, Taehyoung; Choi, Jinsoo; Lee, Gangwoong; Ahn, Junyoung; Park, Jin Soo; Atwood, Samuel A.; Schurman, Misha; Choi, Yongjoo; Chung, Yoomi; Collett, Jeffrey L.

    2015-11-01

    To improve understanding of the sources and chemical properties of particulate pollutants on the western side of the Korean Peninsula, an Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) measured non-refractory fine (PM1) particles from May to November, 2011 at Baengnyeong Island, South Korea. Organic matter and sulfate were generally the most abundant species and exhibited maximum concentrations of 36 μg/m3 and 39 μg/m3, respectively. Nitrate concentrations peaked at 32 μg/m3 but were typically much lower than sulfate and organic matter concentrations. May, September, October, and November featured the highest monthly average concentrations, with lower concentrations typically observed from June through August. Potential source contribution function (PSCF) analysis and individual case studies revealed that transport from eastern China, an area with high SO2 emissions, was associated with high particulate sulfate concentrations at the measurement site. Observed sulfate aerosol sometimes was fully neutralized by ammonium but often was acidic; the average ammonium to sulfate molar ratio was 1.49. Measured species size distributions revealed a range of sulfate particle size distributions with modes between 100 and 600 nm. Organic aerosol source regions were widespread, including contributions from eastern China and South Korea. Positive matrix factorization (PMF) analysis indicated three "factors," or types of organic aerosol, comprising one primary, hydrocarbon-like organic aerosol (HOA) and two oxidized organic aerosol (OOA) components, including a more oxidized (MO-OOA) and a less oxidized (LO-OOA) oxidized organic aerosol. On average, HOA and OOA contributed 21% and 79% of the organic mass (OM), respectively, with the MO-OOA fraction nearly three times as abundant as the LO-OOA fraction. Biomass burning contributions to observed OM were low during the late spring/early summer agricultural burning season in eastern China, since

  10. Characterization of Site for Installing Open Loop Ground Source Heat Pump System

    Science.gov (United States)

    Yun, S. W.; Park, Y.; Lee, J. Y.; Yi, M. J.; Cha, J. H.

    2014-12-01

    This study was conducted to understand hydrogeological properties of site where open loop ground source heat pump system will be installed and operated. Groundwater level and water temperature were hourly measured at the well developed for usage of open loop ground source heat pump system from 11 October 2013 to 8 January 2014. Groundwater was sampled in January and August 2013 and its chemical and isotopic compositions were analyzed. The bedrock of study area is the Jurassic granodiorite that mainly consists of quartz (27.9 to 46.8%), plagioclase (26.0 to 45.5%), and alkali feldspar (9.5 to 18.7%). The groundwater level ranged from 68.30 to 68.94 m (above mean sea level). Recharge rate was estimated using modified watertable fluctuation method and the recharge ratios was 9.1%. The water temperature ranged from 14.8 to 15.0oC. The vertical Increase rates of water temperature were 1.91 to 1.94/100 m. The water temperature showed the significant seasonal variation above 50 m depth, but had constant value below 50 m depth. Therefore, heat energy of the groundwater can be used securely in open loop ground source heat pump system. Electrical conductivity ranged from 120 to 320 µS/cm in dry season and from 133 to 310 µS/cm in wet season. The electrical conductivity gradually decreased with depth. In particular, electrical conductivity in approximately 30 m depth decreased dramatically (287 to 249 µS/cm) in wet season. The groundwater was Ca-HCO3 type. The concentrations of dissolved components did not show the vertically significant variations from 0 to 250 m depth. The δ18O and δD ranged from -9.5 to -9.4‰ and from -69 to -68‰. This work is supported by the New and Renewable Energy of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Knowledge Economy (No.20123040110010).

  11. Preparation and characterization of B4C coatings for advanced research light sources

    Science.gov (United States)

    Störmer, Michael; Siewert, Frank; Sinn, Harald

    2016-01-01

    X-ray optical elements are required for beam transport at the current and upcoming free-electron lasers and synchrotron sources. An X-ray mirror is a combination of a substrate and a coating. The demand for large mirrors with single layers consisting of light or heavy elements has increased during the last few decades; surface finishing technology is currently able to process mirror lengths up to 1 m with microroughness at the sub-nanometre level. Additionally, thin-film fabrication is able to deposit a suitable single-layer material, such as boron carbide (B4C), some tens of nanometres thick. After deposition, the mirror should provide excellent X-ray optical properties with respect to coating thickness errors, microroughness values and slope errors; thereby enabling the mirror to transport the X-ray beam with high reflectivity, high beam flux and an undistorted wavefront to an experimental station. At the European XFEL, the technical specifications of the future mirrors are extraordinarily challenging. The acceptable shape error of the mirrors is below 2 nm along the whole length of 1 m. At the Helmholtz-Zentrum Geesthacht (HZG), amorphous layers of boron carbide with thicknesses in the range 30–60 nm were fabricated using the HZG sputtering facility, which is able to cover areas up to 1500 mm long by 120 mm wide in one step using rectangular B4C sputtering targets. The available deposition area is suitable for the specified X-ray mirror dimensions of upcoming advanced research light sources such as the European XFEL. The coatings produced were investigated by means of X-ray reflectometry and interference microscopy. The experimental results for the B4C layers are discussed according to thickness uniformity, density, microroughness and thermal stability. The variation of layer thickness in the tangential and sagittal directions was investigated in order to estimate the achieved level of uniformity over the whole deposition area, which is

  12. Characterization and source identification of hydrocarbons in water samples using multiple analytical techniques

    International Nuclear Information System (INIS)

    A study was conducted in which several analytical techniques were used to identify and characterize trace petroleum-related hydrocarbons and other volatile organic compounds in groundwater samples that were collected from a bedrock aquifer used for drinking water. A previous study had confirmed the presence of chlorinated compounds in the groundwater. The study presented in this paper was aimed at confirming the presence or absence of gasoline or other petroleum products in those samples. A service station was operated on this site for about 10 years and the adjacent property was owned by a chemicals handling company. Both operations were considered to be potentially responsible parties to the contamination of the aquifer. The difference in contaminants at different depths of the aquifer was examined using a variety of analytical techniques such as gas chromatography, mass spectrometry, flame-ionization detection, solid-phase-micro-extractor and head space. Chemical characterization results showed that the hydrocarbons found in the water samples near the surface were either gasoline or heavy petroleum products. The significant distribution of 5 target petroleum-characteristic alkylated polyaromatic hydrocarbon homologues and biomarkers confirmed the presence of another heavy petroleum product. The concentrations of the total petroleum hydrocarbon (TPH) and BTEX were found to be 1070 and 155 μg/kg of water for the samples near the surface. Results also showed that the deep groundwater samples collected at a depths ranging between 15 to 60 metres were also contaminated but to a much lesser degree. The concentrations of the TPH and BTEX were found to be only 130 and 2.6 μg/kg of water for the deep groundwater samples. The study also revealed that the groundwater was contaminated by a variety of volatile chlorinated compounds. 18 refs., 2 tabs., 7 figs

  13. Microbial characterization for the Source-Term Waste Test Program (STTP) at Los Alamos

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, P.A.; Strietelmeier, B.A.; Pansoy-Hjelvik, M.E.; Villarreal, R.

    1999-04-01

    The effects of microbial activity on the performance of the proposed underground nuclear waste repository, the Waste Isolation Pilot Plant (WIPP) at Carlsbad, New Mexico are being studied at Los Alamos National Laboratory (LANL) as part of an ex situ large-scale experiment. Actual actinide-containing waste is being used to predict the effect of potential brine inundation in the repository in the distant future. The study conditions are meant to simulate what might exist should the underground repository be flooded hundreds of years after closure as a result of inadvertent drilling into brine pockets below the repository. The Department of Energy (DOE) selected LANL to conduct the Actinide Source-Term Waste Test Program (STTP) to confirm the predictive capability of computer models being developed at Sandia National Laboratory.

  14. Microbial characterization for the Source-Term Waste Test Program (STTP) at Los Alamos

    International Nuclear Information System (INIS)

    The effects of microbial activity on the performance of the proposed underground nuclear waste repository, the Waste Isolation Pilot Plant (WIPP) at Carlsbad, New Mexico are being studied at Los Alamos National Laboratory (LANL) as part of an ex situ large-scale experiment. Actual actinide-containing waste is being used to predict the effect of potential brine inundation in the repository in the distant future. The study conditions are meant to simulate what might exist should the underground repository be flooded hundreds of years after closure as a result of inadvertent drilling into brine pockets below the repository. The Department of Energy (DOE) selected LANL to conduct the Actinide Source-Term Waste Test Program (STTP) to confirm the predictive capability of computer models being developed at Sandia National Laboratory

  15. Mineralogical Characterization of Baptistina Asteroid Family: Implications for K/T Impactor Source

    CERN Document Server

    Reddy, Vishnu; Lazzaro, Daniela; Michtchenko, Tatiana A; Gaffey, Michael J; Kelley, Michael S; Diniz, Thais Mothé; Candal, Alvaro Alvarez; Moskovitz, Nicholas A; Cloutis, Edward A; Ryan, Erin L; 10.1016/j.icarus.2011.08.027

    2011-01-01

    Bottke et al. (2007) linked the catastrophic formation of Baptistina Asteroid Family (BAF) to the K/T impact event. This linkage was based on dynamical and compositional evidence, which suggested the impactor had a composition similar to CM2 carbonaceous chondrites. However, our recent study (Reddy et al. 2009) suggests that the composition of (298) Baptistina is similar to LL-type ordinary chondrites rather than CM2 carbonaceous chondrites. This rules out any possibility of it being related to the source of the K/T impactor, if the impactor was of CM-type composition. Mineralogical study of asteroids in the vicinity of BAF has revealed a plethora of compositional types suggesting a complex formation and evolution environment. A detailed compositional analysis of 16 asteroids suggests several distinct surface assemblages including ordinary chondrites (Gaffey SIV subtype), primitive achondrites (Gaffey SIII subtype), basaltic achondrites (Gaffey SVII subtype and V-type), and a carbonaceous chondrite. Based on ...

  16. Source characterization of selected North Caspian events from the relative excitation of regional phases. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Niazi, M.

    1981-11-01

    Seismograms of seven recent events (presumed underground nuclear explosions) which occurred during 1976-1979 in the North Caspian Sea region of the western Soviet Kazakh are compared at regional distances for their relative source excitation characteristics. The body wave magnitude estimates of these events range from 5.1 to 6.0. The data consist of analog and digital records collected at stations ranging in instrumental sophistication from temporary sites with single component smoke drum capability to those of SRO, ASRO and array (ILPA) configurations with digitally recorded down-hole observations. The amplitude and frequency measurements of the analog seismograms for the first arrival and the peak amplitude of P coda as well as for the clear S wave signals recorded for different events at the same station are compared.

  17. A characterization and optimization study of Gamble II as an X-ray bremsstrahlung source

    International Nuclear Information System (INIS)

    The adverse effects of radiation on solid state devices are strongly spectrum dependent. It is thus essential that the radiation spectrum from flash x-ray sources be available when they are used as facilities for testing electronic components. This paper describes a preliminary study in which previously developed computer codes were used to calculate the radiation spectrum produced by NRL's Gamble II pulsed power generator. To determine how well the calculated spectrum matched the experimental one, doses in CaF2-Mn TLD's were computed for the dosimeters placed behind various thicknesses of Cu and Pb filters and compared with the experimentally measured doses. Using a diode model that was consistent with presently understood electron beam behavior, a spectrum was generated which predicted TLD doses to within about 15% of the experimentally measured values

  18. Enhanced biological phosphorus removal. Carbon sources, nitrate as electron acceptor, and characterization of the sludge community

    Energy Technology Data Exchange (ETDEWEB)

    Christensson, M.

    1997-10-01

    Enhanced biological phosphorus removal (EBPR) was studied in laboratory scale experiments as well as in a full scale EBPR process. The studies were focused on carbon source transformations, the use of nitrate as an electron acceptor and characterisation of the microflora. A continuous anaerobic/aerobic laboratory system was operated on synthetic wastewater with acetate as sole carbon source. An efficient EBPR was obtained and mass balances over the anaerobic reactor showed a production of 1.45 g poly-{beta}-hydroxyalcanoic acids (PHA), measured as chemical oxygen demand (COD), per g of acetic acid (as COD) taken up. Furthermore, phosphate was released in the anaerobic reactor in a ratio of 0.33 g phosphorus (P) per g PHA (COD) formed and 0.64 g of glycogen (COD) was consumed per g of acetic acid (COD) taken up. Microscopic investigations revealed a high amount of polyphosphate accumulating organisms (PAO) in the sludge. Isolation and characterisation of bacteria indicated Acinetobacter spp. to be abundant in the sludge, while sequencing of clones obtained in a 16S rDNA clone library showed a large part of the bacteria to be related to the high mole % G+C Gram-positive bacteria and only a minor fraction to be related to the gamma-subclass of proteobacteria to which Acinetobacter belongs. Operation of a similar anaerobic/aerobic laboratory system with ethanol as sole carbon source showed that a high EBPR can be achieved with this compound as carbon source. However, a prolonged detention time in the anaerobic reactor was required. PHA were produced in the anaerobic reactor in an amount of 1.24 g COD per g of soluble DOC taken up, phosphate was released in an amount of 0.4-0.6 g P per g PHA (COD) produced and 0.46 g glycogen (COD) was consumed per g of soluble COD taken up. Studies of the EBPR in the UCT process at the sewage treatment plant in Helsingborg, Sweden, showed the amount of volatile fatty acids (VFA) available to the PAO in the anaerobic stage to be

  19. Achira as a source of biodegradable materials: Isolation and characterization of nanofibers.

    Science.gov (United States)

    Andrade-Mahecha, Margarita María; Pelissari, Franciele Maria; Tapia-Blácido, Delia Rita; Menegalli, Florencia Cecilia

    2015-06-01

    In this study, variations in the delignification and bleaching stages, acid hydrolysis and high-pressure homogenization, led to the development of 12 different treatments applied for obtaining nanofibers using fibrous residues arising from the starch extraction process from the achira rhizomes. The treatments were evaluated based on some properties and characteristics of nanofibers such as: morphology and size (by means of transmission electron microscopy), surface charge (by means of zeta potential measurements), crystallinity index (by means of X-ray diffraction analysis) and functional groups (by means of infrared spectroscopy). In general, the nanofibers showed particle diameters between 13.8 and 37.2nm, length between 832.8 and 2223.8nm and high crystallinity index (57.5% and 69.8%) compared with achira fibrous residue (17.3%). The results evidenced that fibrous residue from achira rhizomes can be used as a source of biodegradable materials of commercial interest. PMID:25843874

  20. Electron Beam Production and Characterization for the PLEIADES Thomson X-ray Source

    Energy Technology Data Exchange (ETDEWEB)

    Brown, W J; Hartemann, F V; Tremaine, A M; Springer, P T; Le Sage, G P; Barty, C P J; Rosenzweig, J B; Crane, J K; Cross, R R; Fittinghoff, D B; Gibson, D J; Slaughter, D R; Anderson, S

    2002-10-14

    We report on the performance of an S-band RF photocathode electron gun and accelerator for operation with the PLEIADES Thomson x-ray source at LLNL. Simulations of beam production, transport, and focus are presented. It is shown that a 1 ps, 500 pC electron bunch with a normalized emittance of less than 5 {pi}mm-mrad can be delivered to the interaction point. Initial electron measurements are presented. Calculations of expected x-ray flux are also performed, demonstrating an expected peak spectral brightness of 10{sup 20} photons/s/mm{sup 2}/mrad{sup 2}/0.1% bandwidth. Effects of RF phase jitter are also presented, and planned phase measurements and control methods are discussed.

  1. Deposition and characterization of Pt nanocluster films by means of gas aggregation cluster source

    Energy Technology Data Exchange (ETDEWEB)

    Kylián, Ondřej, E-mail: ondrej.kylian@gmail.com; Prokeš, Jan; Polonskyi, Oleksandr; Čechvala, Juraj; Kousal, Jaroslav; Pešička, Josef; Hanuš, Jan; Biederman, Hynek

    2014-11-28

    In this study we report on the deposition of Pt nanocluster films prepared by gas aggregation source that was operated with argon as working gas. The aim of this study was optimization of deposition process as well as determination of properties of deposited nanocluster films and their temporal stability. It was found that the production of Pt nanoclusters reached maximum value for pressure of 100 Pa and increases monotonously with magnetron current. The deposition rate at optimized deposition conditions was 0.7 nm of the Pt nanocluster film per second. Deposited films were porous and composed of 4 nm Pt nanoclusters. The nanoclusters were metallic and no sights of their oxidation were observed after 1 year on open air as witnessed by X-ray photoelectron spectroscopy. Regarding the electrical properties, a dramatic decrease of the resistivity was observed with increasing amount of deposited nanoclusters. This decrease saturated for the films approximately 50 nm thick. Such behavior indicates transition between different mechanisms of electrical conductivity: charge hopping for thin discontinuous films and current conduction through conducting path formed when higher amount of nanoclusters is deposited. Different mechanisms of electrical conduction for thin and thick layers of Pt were confirmed by subsequent investigation of temperature dependence of resistivity. In addition, no changes in resistivity were observed after one year on open air that confirms stability of produced Pt nanocluster films. - Highlights: • Pt nanocluster films were deposited by gas aggregation nanocluster source. • Conditions leading to effective deposition of Pt nanocluster films were found. • Deposited nanocluster films have good temporal stability. • Electrical properties of Pt films were found to depend on their thickness.

  2. Aspects of petrochemical pollution in southeastern Louisiana (USA): pre-Katrina background and source characterization.

    Science.gov (United States)

    Iqbal, Javed; Gisclair, David; McMillin, Debra J; Portier, Ralph J

    2007-09-01

    Background petroleum pollution before Hurricane Katrina in southeastern Louisiana (USA) coastal sediments was evaluated at 320 locations in three consecutive years for polycyclic aromatic hydrocarbons (PAHs), saturated alkanes (nC9-nC35), and petroleum biomarker compounds (hopanes, steranes, pristane, and phytane). Approximately 90% of the sample locations had a total PAH concentration of less than 2.0 microg/g and total saturated alkane concentration of less than 17 microg/g, with 50% indicating a total PAH concentration of less than 200 ng/g. Upper limit or baseline high concentration for total PAHs was 1.5 microg/g, comparable to the 2.18 microg/g reported for the National Status and Trends (NST) Program of the National Oceanic and Atmospheric Administration (NOAA). Thus, 85% of sites were below the baseline high concentration. Baseline high total PAHs at 6% of the sites (described as land) was 5.1 microg/g, comparable to the 4 microg/g benchmark calculated for NST. The three-year average total PAH concentration for 95% of the sites was less than 7.5 microg/g, a defined limit of fivefold the baseline high concentration. Samples indicated petrogenic, pyrogenic, and natural/biogenic hydrocarbon inputs. Contaminant levels exceeded the state soil screening limits at only 3% of the 320 locations. Federal screening limits proposed by the NOAA for ecological effects were exceeded at only 18% of the sites (including those sites exceeding the state limit). Only 4% of the sites had concentrations exceeding the NOAA effect range-low (ER-L) in more than one collection year. At least 61% of the analytes exceeding the ER-L were pyrogenic source indicators. Source-fingerprint analysis of these selected samples showed 10 samples with notable petroleum contamination, whereas six indicated pyrogenic input. Of all samples collected, only one site showed relatively fresh/lightly weathered petroleum.

  3. Enhanced nitrogen removal in a wastewater treatment process characterized by carbon source manipulation with biological adsorption and sludge hydrolysis.

    Science.gov (United States)

    Liu, Hongbo; Zhao, Fang; Mao, Boyang; Wen, Xianghua

    2012-06-01

    An innovative adsorption/nitrification/denitrification/sludge-hydrolysis wastewater treatment process (ENRS) characterized by carbon source manipulation with a biological adsorption unit and a sludge hydrolysis unit was developed to enhance nitrogen removal and reduce sludge production for municipal wastewater treatment. The system presented good performance in pollutants removal, yielding the effluent with average COD, NH(4)(+)-N, TN and TP of 48.5, 0.6, 13.2 and 1.0 mg/L, respectively. Sixty percent of the total carbon source in the influent was concentrated and separated by the quick adsorption of activated sludge, providing the possibilities of reusing waste carbon source in the denitrification tank and accumulating nitrobacteria in the nitrification tank. Low temperature of 6-15 °C and high hydraulic loading rate of 3.0-15.0 m(3)/d did not affect NH(4)(+)-N removal performance, yielding the NH(4)(+)-N of lower 1.0 mg/L in the effluent. Furthermore, 50% of the residual sludge in the ENRS system could be transformed into soluble COD (SCOD) by alkaline thermal hydrolysis with temperature of 60 °C and pH of 11, and the hydrolyzed carbon could completely substitute methanol as a good quality carbon to support high efficient denitrification.

  4. Characterization and applications of a tunable, laser-based, MeV-class Compton-scattering γ-ray source

    Science.gov (United States)

    Albert, F.; Anderson, S. G.; Gibson, D. J.; Hagmann, C. A.; Johnson, M. S.; Messerly, M.; Semenov, V.; Shverdin, M. Y.; Rusnak, B.; Tremaine, A. M.; Hartemann, F. V.; Siders, C. W.; McNabb, D. P.; Barty, C. P. J.

    2010-07-01

    A high peak brilliance, laser-based Compton-scattering γ-ray source, capable of producing quasimonoenergetic photons with energies ranging from 0.1 to 0.9 MeV has been recently developed and used to perform nuclear resonance fluorescence (NRF) experiments. Techniques for characterization of γ-ray beam parameters are presented. The key source parameters are the size (0.01mm2), horizontal and vertical divergence (6×10mrad2), duration (16 ps), and spectrum and intensity (105photons/shot). These parameters are summarized by the peak brilliance, 1.5×1015photons/mm2/mrad2/s/0.1% bandwidth, measured at 478 keV. Additional measurements of the flux as a function of the timing difference between the drive laser pulse and the relativistic photoelectron bunch, γ-ray beam profile, and background evaluations are presented. These results are systematically compared to theoretical models and computer simulations. NRF measurements performed on Li7 in LiH demonstrate the potential of Compton-scattering photon sources to accurately detect isotopes in situ.

  5. Medicina array demonstrator: calibration and radiation pattern characterization using a UAV-mounted radio-frequency source

    Science.gov (United States)

    Pupillo, G.; Naldi, G.; Bianchi, G.; Mattana, A.; Monari, J.; Perini, F.; Poloni, M.; Schiaffino, M.; Bolli, P.; Lingua, A.; Aicardi, I.; Bendea, H.; Maschio, P.; Piras, M.; Virone, G.; Paonessa, F.; Farooqui, Z.; Tibaldi, A.; Addamo, G.; Peverini, O. A.; Tascone, R.; Wijnholds, S. J.

    2015-06-01

    One of the most challenging aspects of the new-generation Low-Frequency Aperture Array (LFAA) radio telescopes is instrument calibration. The operational LOw-Frequency ARray (LOFAR) instrument and the future LFAA element of the Square Kilometre Array (SKA) require advanced calibration techniques to reach the expected outstanding performance. In this framework, a small array, called Medicina Array Demonstrator (MAD), has been designed and installed in Italy to provide a test bench for antenna characterization and calibration techniques based on a flying artificial test source. A radio-frequency tone is transmitted through a dipole antenna mounted on a micro Unmanned Aerial Vehicle (UAV) (hexacopter) and received by each element of the array. A modern digital FPGA-based back-end is responsible for both data-acquisition and data-reduction. A simple amplitude and phase equalization algorithm is exploited for array calibration owing to the high stability and accuracy of the developed artificial test source. Both the measured embedded element patterns and calibrated array patterns are found to be in good agreement with the simulated data. The successful measurement campaign has demonstrated that a UAV-mounted test source provides a means to accurately validate and calibrate the full-polarized response of an antenna/array in operating conditions, including consequently effects like mutual coupling between the array elements and contribution of the environment to the antenna patterns. A similar system can therefore find a future application in the SKA-LFAA context.

  6. Preparation and characterization of B{sub 4}C coatings for advanced research light sources

    Energy Technology Data Exchange (ETDEWEB)

    Störmer, Michael, E-mail: michael.stoermer@hzg.de [Helmholtz-Zentrum Geesthacht, Max-Planck-Strasse 1, D-21502 Geesthacht (Germany); Siewert, Frank [Helmholtz-Zentrum Berlin, Albert-Einstein-Strasse 15, 12489 Berlin (Germany); Sinn, Harald [European XFEL GmbH, Albert-Einstein-Ring 19, 22761 Hamburg (Germany)

    2016-01-01

    The challenging specifications for long X-ray mirrors for upcoming free-electron lasers can be achieved, especially for maintaining below 2 nm peak-to-valley shape error along the optical aperture of approximately 1 m-long mirrors. X-ray optical elements are required for beam transport at the current and upcoming free-electron lasers and synchrotron sources. An X-ray mirror is a combination of a substrate and a coating. The demand for large mirrors with single layers consisting of light or heavy elements has increased during the last few decades; surface finishing technology is currently able to process mirror lengths up to 1 m with microroughness at the sub-nanometre level. Additionally, thin-film fabrication is able to deposit a suitable single-layer material, such as boron carbide (B{sub 4}C), some tens of nanometres thick. After deposition, the mirror should provide excellent X-ray optical properties with respect to coating thickness errors, microroughness values and slope errors; thereby enabling the mirror to transport the X-ray beam with high reflectivity, high beam flux and an undistorted wavefront to an experimental station. At the European XFEL, the technical specifications of the future mirrors are extraordinarily challenging. The acceptable shape error of the mirrors is below 2 nm along the whole length of 1 m. At the Helmholtz-Zentrum Geesthacht (HZG), amorphous layers of boron carbide with thicknesses in the range 30–60 nm were fabricated using the HZG sputtering facility, which is able to cover areas up to 1500 mm long by 120 mm wide in one step using rectangular B{sub 4}C sputtering targets. The available deposition area is suitable for the specified X-ray mirror dimensions of upcoming advanced research light sources such as the European XFEL. The coatings produced were investigated by means of X-ray reflectometry and interference microscopy. The experimental results for the B{sub 4}C layers are discussed according to thickness uniformity, density

  7. Characterization of the primary source of electrons in linear accelerators in clinical use; Caracterizacion de la fuente primaria de electrones en aceleradores lineales de uso clinico

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Extremera, M.; Gonzalez Infantes, W.; Lallena rojo, A. M.; Anguiano Millan, M.

    2013-07-01

    Monte Carlo simulation is currently considered the most accurate method for calculations of doses due to electrons. The objective of the work is the characterization of the primary source of electrons from an accelerator of clinical use with Monte Carlo simulation, in order to build a model of sources involving a substantial saving of time of calculation in the simulation of treatment. (Author)

  8. IDENTIFICATION AND CHARACTERIZATION OF FIVE NON- TRADITIONAL SOURCE CATEGORIES: CATASTROPHIC/ACCIDENTAL RELEASES, VEHICLE REPAIR FACILITIES, RECYCLING, PESTICIDE APPLICATION, AND AGRICULTURAL OPERATIONS

    Science.gov (United States)

    The report gives results of work that is part of EPA's program to identify and characterize emissions sources not currently accounted for by either the existing Aerometric Information Retrieval System (AIRS) or State Implementation Plan (SIP) area source methodologies and to deve...

  9. Immunosuppression in murine renal cell carcinoma. I. Characterization of extent, severity and sources.

    Science.gov (United States)

    Gregorian, S K; Battisto, J R

    1990-01-01

    Four cell-mediated immunological responses related to tumor elimination have been examined in mice injected with a transplantable renal cell carcinoma (Renca). Lymphokine-activated killer (LAK) cells generated in vitro from spleen cells of normal mice were capable of attacking Renca, EL-4, P815 and YAC-1 targets, but those from mice bearing Renca for 3 weeks could not. Natural killer activity, stimulated in vivo by administering poly(I) poly(C), was less than 50% of normal in Renca-bearing hosts. In addition, development of cytotoxic T lymphocytes to allogeneic targets was markedly inhibited in mice possessing the renal tumor. Finally, the delayed hypersensitivity response to a dermally applied hapten was approximately 70% less than normal in tumor-bearing mice, no matter whether the tumor existed subcutaneously or intrarenally. A kinetic study of the development of non-responsiveness using the LAK assay showed onset of poor response at 1 week, which became maximal within 3 weeks following receipt of tumor subcutaneously. The immunological depression was seen to be attributable in part to suppressor cells present among spleen cells but not bone marrow cells of tumor-bearing hosts. The suppressor cells prevented in vitro LAK generation by normal spleen cells and, when adoptively transferred to normal mice, they inhibited natural killer stimulation and delayed hypersensitivity generation. Another source of immunological down-regulation was provided by Renca cells themselves. Incorporation of Renca cells that had been X-irradiated with 30,000 rad into cultures of normal and Renca-derived splenic cells suppressed replication of both almost completely. Furthermore, the presence of X-irradiated Renca cells in cultures of normal spleen cells prevented development of LAK cells. Thus, the suppression seen in Renca-bearing mice derives from multiple sources and whether each is in any way related to the other has been discussed. Identification of the phenotypes of cells

  10. Iterative de-convolution of the local waveforms: Characterization of the seismic sources in Kachchh, India

    Science.gov (United States)

    Mandal, Prantik; Satyamurty, C.; Raju, I. P.

    2009-12-01

    The deviatoric and double couple (DC) constrained moment tensor inversions of multiple point sources (10-20 s) for regional (or local) earthquakes, developed by Zahradnik et al. (2005), has been applied on the data of nine significant Bhuj aftershocks of Mw4.4- Mw5.6 recorded at three-component 5-15 accelerograph and 5-11 seismograph stations (epicentral distances < 130 km). The deviatoric moment tensor solutions of events on the north Wagad fault (NWF) in the 15-29 km depth range reveal a systematic depth-wise variation in the faulting patterns. At shallow depth (~ 15 km), they suggest a left lateral strike-slip movement with a minor reverse component along a south dipping plane (~ 61°), whereas, at 18-22 km depth range they change to pure reverse movement on a preferred south dipping plane (10-54°) and finally they change to the normal movement with minor strike-slip (S-S) component at deeper (25-29 km) depth range. The deviatoric MT solution of one event on the south Wagad fault (SWF) suggests a reverse movement with a minor S-S component on a 35° southeast dipping plane at 24 km depth. The deviatoric MT solutions for two events on the Gedi fault reveal a reverse movement with a minor left-lateral strike-slip component on an E-W trending and south dipping (40-61°) plane at 3-4 km depth. Whereas, one event on the Island belt fault (IBF) suggests a right lateral strike slip movement with a normal component on an almost vertical (~ 79°) plane at 29 km depth. The deviatoric moment tensor solutions of all the nine events show a larger (94-99%) double-couple (DC) component at shallow (3-15 km) depth range suggesting domination of brittle failure in the upper crust beneath the Kachchh region. However, the deeper events show larger non-DC (i.e. compensated linear vector dipole, CLVD) component suggesting increase in deviation from the double-couple (DC) solution in the lower crust (15-30 km depth range). This increase in non-DC component could be attributed to the

  11. Synthesis and characterization of functionalized dithiocarbamates: New single-source precursors for CdS

    Science.gov (United States)

    Srinivasan, Narayanaswamy

    2014-01-01

    Novel single-molecular precursors for CdS are prepared by reacting functionalized secondary amine and CS2 with cadmium acetate dihydrate. All these precursors are characterized by elemental analysis, infrared spectroscopy and solid-state 13C NMR. CdS semiconductor nanoparticles are synthesized using these precursors by a single-step solvothermal method with ethylenediamine at 117 °C. The synthesized semiconductor nanoparticles are investigated by infra-red spectroscopy, powder X-ray diffraction analysis, energy-dispersive X-ray spectroscopy analysis, scanning electron microscopy, field emission scanning electron microscopy, transmission electron microscopy, high resolution transmission microscopy, selected area electron diffraction analysis and Raman spectroscopy. The synthesized CdS are hexagonal (zinc wurtzite) crystalline material, which are indicative of the reduction of particles. Comparison with the CdS and the mixture of CdS/CdSṡ0.5gl revealed that the CdS/CdSṡ0.5gl exhibited a well crystalline structure.

  12. A wide-acceptance Compton spectrometer for spectral characterization of a medical x-ray source

    Science.gov (United States)

    Espy, Michelle A.; Gehring, A.; Belian, A.; Haines, T.; Hunter, J.; James, M.; Klasky, M.; Mendez, J.; Moir, D.; Sedillo, R.; Shurter, R.; Stearns, J.; Van Syoc, K.; Volegov, P.

    2016-03-01

    Accurate knowledge of the x-ray spectra used in medical treatment and radiography is important for dose calculations and material decomposition analysis. Indirect measurements via transmission through materials are possible. However, such spectra are challenging to measure directly due to the high photon fluxes. One method of direct measurement is via a Compton spectrometer (CS) method. In this approach, the x-rays are converted to a much lower flux of electrons via Compton scattering on a converter foil (typically beryllium or aluminum). The electrons are then momentum selected by bending in a magnetic field. With tight angular acceptance of electrons into the magnet of ~ 1 deg, there is a linear correlation between incident photon energy and electron position recorded on an image plate. Here we present measurements of Bremsstrahlung spectrum from a medical therapy machine, a Scanditronix M22 Microtron. Spectra with energy endpoints from 6 to 20 MeV are directly measured, using a CS with a wide energy range from 0.5 to 20 MeV. We discuss the sensitivity of the device and the effects of converter material and collimation on the accuracy of the reconstructed spectra. Approaches toward improving the sensitivity, including the use of coded apertures, and potential future applications to characterization of spectra are also discussed.

  13. Characterization of Calcium Compounds in Opuntia ficus indica as a Source of Calcium for Human Diet

    Directory of Open Access Journals (Sweden)

    Isela Rojas-Molina

    2015-01-01

    Full Text Available Analyses of calcium compounds in cladodes, soluble dietary fiber (SDF, and insoluble dietary fiber (IDF of Opuntia ficus indica are reported. The characterization of calcium compounds was performed by using Scanning Electron Microscopy, Energy Dispersive Spectrometry, X-ray diffraction, and infrared spectroscopy. Atomic Absorption Spectroscopy and titrimetric methods were used for quantification of total calcium and calcium compounds. Whewellite (CaC2O4·H2O, weddellite (CaC2O4·(H2O2.375, and calcite (CaCO3 were identified in all samples. Significant differences (P≤0.05 in the total calcium contents were detected between samples. CaC2O4·H2O content in cladodes and IDF was significantly higher (P≤0.05 in comparison to that observed in SDF, whereas minimum concentration of CaCO3 was detected in IDF with regard to CaCO3 contents observed in cladodes and SDF. Additionally, molar ratio oxalate : Ca2+ in all samples changed in a range from 0.03 to 0.23. These results support that calcium bioavailability in O. ficus indica modifies according to calcium compounds distribution.

  14. Hydraulic/partitioning tracer tomography for DNAPL source zone characterization: small-scale sandbox experiments.

    Science.gov (United States)

    Illman, Walter A; Berg, Steven J; Liu, Xiaoyi; Massi, Antonio

    2010-11-15

    Dense nonaqueous phase liquids (DNAPL) are prevalent at a large number of sites throughout the world. The variable release history, unstable flow, and geologic heterogeneity make the spatial distribution of DNAPLs complex. This causes difficulties in site remediation contributing to long-term groundwater contamination for decades to centuries. We present laboratory experiments to demonstrate the efficacy of Sequential Successive Linear Estimator (SSLE) algorithm that images DNAPL source zones. The algorithm relies on the fusion of hydraulic and partitioning tracer tomography (HPTT) to derive the best estimate of the K heterogeneity, DNAPL saturation (S(N)) distribution, and their uncertainty. The approach is nondestructive and can be applied repeatedly. Results from our laboratory experiments show that S(N) distributions compare favorably with DNAPL distributions observed in the sandbox but not so with local saturation estimates from core samples. We also found that the delineation of K heterogeneity can have a large impact on computed S(N) distributions emphasizing the importance of accurate delineation of hydraulic heterogeneity.

  15. Density currents in the Chicago River: Characterization, effects on water quality, and potential sources

    Science.gov (United States)

    Jackson, P. Ryan; Garcia, Carlos M.; Oberg, Kevin A.; Johnson, Kevin K.; Garcia, Marcelo H.

    2008-01-01

    Bidirectional flows in a river system can occur under stratified flow conditions and in addition to creating significant errors in discharge estimates, the upstream propagating currents are capable of transporting contaminants and affecting water quality. Detailed field observations of bidirectional flows were made in the Chicago River in Chicago, Illinois in the winter of 2005-06. Using multiple acoustic Doppler current profilers simultaneously with a water-quality profiler, the formation of upstream propagating density currents within the Chicago River both as an underflow and an overflow was observed on three occasions. Density differences driving the flow primarily arise from salinity differences between intersecting branches of the Chicago River, whereas water temperature is secondary in the creation of these currents. Deicing salts appear to be the primary source of salinity in the North Branch of the Chicago River, entering the waterway through direct runoff and effluent from a wastewater-treatment plant in a large metropolitan area primarily served by combined sewers. Water-quality assessments of the Chicago River may underestimate (or overestimate) the impairment of the river because standard water-quality monitoring practices do not account for density-driven underflows (or overflows). Chloride concentrations near the riverbed can significantly exceed concentrations at the river surface during underflows indicating that full-depth parameter profiles are necessary for accurate water-quality assessments in urban environments where application of deicing salt is common.

  16. A new method for characterizing beta-ray ophthalmic applicator sources

    International Nuclear Information System (INIS)

    A technique is described which enables one to obtain detailed dose characteristics of 90Sr beta-ray ophthalmic applicators. A radiochromic radiation detector which is a solid-state solution of hexahydroxyethyl pararosaniline cyanide in a nylon polymer (i.e., thin foil), has been used to determine the surface dose rate and dose distribution of these sources. The detectors are rugged, easily handled, have an equivalent response (optical density per unit absorbed dose) to photons and electrons, and produce high-resolution images. They have been found useful for this application due to the high surface dose rates [0.10-1.0 Gy (H2O)/s] and their low sensitivity (approximately 10(4) Gy for an optical density of 1.0). The foils have been evaluated on a He-Ne scanning laser densitometer with a resolution of 0.3 mum. Comparison with NIST (formerly NBS) extrapolation ionization chamber measurements indicates surface dose-rate agreement within 6%. Spectral dosimetric characteristics are presented and discussed

  17. EchoSeed Model 6733 Iodine-125 brachytherapy source: Improved dosimetric characterization using the MCNP5 Monte Carlo code

    Energy Technology Data Exchange (ETDEWEB)

    Mosleh-Shirazi, M. A.; Hadad, K.; Faghihi, R.; Baradaran-Ghahfarokhi, M.; Naghshnezhad, Z.; Meigooni, A. S. [Center for Research in Medical Physics and Biomedical Engineering and Physics Unit, Radiotherapy Department, Shiraz University of Medical Sciences, Shiraz 71936-13311 (Iran, Islamic Republic of); Radiation Research Center and Medical Radiation Department, School of Engineering, Shiraz University, Shiraz 71936-13311 (Iran, Islamic Republic of); Comprehensive Cancer Center of Nevada, Las Vegas, Nevada 89169 (United States)

    2012-08-15

    This study primarily aimed to obtain the dosimetric characteristics of the Model 6733 {sup 125}I seed (EchoSeed) with improved precision and accuracy using a more up-to-date Monte-Carlo code and data (MCNP5) compared to previously published results, including an uncertainty analysis. Its secondary aim was to compare the results obtained using the MCNP5, MCNP4c2, and PTRAN codes for simulation of this low-energy photon-emitting source. The EchoSeed geometry and chemical compositions together with a published {sup 125}I spectrum were used to perform dosimetric characterization of this source as per the updated AAPM TG-43 protocol. These simulations were performed in liquid water material in order to obtain the clinically applicable dosimetric parameters for this source model. Dose rate constants in liquid water, derived from MCNP4c2 and MCNP5 simulations, were found to be 0.993 cGyh{sup -1} U{sup -1} ({+-}1.73%) and 0.965 cGyh{sup -1} U{sup -1} ({+-}1.68%), respectively. Overall, the MCNP5 derived radial dose and 2D anisotropy functions results were generally closer to the measured data (within {+-}4%) than MCNP4c and the published data for PTRAN code (Version 7.43), while the opposite was seen for dose rate constant. The generally improved MCNP5 Monte Carlo simulation may be attributed to a more recent and accurate cross-section library. However, some of the data points in the results obtained from the above-mentioned Monte Carlo codes showed no statistically significant differences. Derived dosimetric characteristics in liquid water are provided for clinical applications of this source model.

  18. Source to sink characterization of dissolved organic matter in a tropical karst system

    Science.gov (United States)

    Lechleitner, Franziska; Lang, Susan Q.; McIntyre, Cameron; Baldini, James U. L.; Dittmar, Thorsten; Eglinton, Timothy I.

    2016-04-01

    Karst systems are widespread surface features present on all continents. They are characterized by complex hydrology with a multitude of possible flow regimes, from diffuse seepage through the host rock to fracture flow in larger conduits. As stalagmite proxy records are important indicators of past terrestrial climate conditions, detailed understanding of the biogeochemistry of cave systems and their relationships to the overlying karst network is crucial. Microbial communities that drive the carbon cycle in caves are nourished by dissolved organic matter (DOM) carried with water into the cave system. Water samples from the Yok Balum cave in Belize were collected for DOM analysis, including soil waters, drip waters and pool waters from inside the cave. Additionally, DOM extracts from a stalagmite from the same cave were analysed to examine DOM signatures and test their applicability for reconstruction of environmental conditions. Ultrahigh-resolution mass spectrometry (via the ESI-FT-ICR-MS technique) yielded detailed molecular fingerprints on DOM from these samples. Several thousand molecular formulae of DOM compounds were identified. In addition, radiocarbon analyses were performed on the DOM samples to gain information on karst turnover times. A principal component analysis of the molecular data revealed a clear gradient between soil waters and cave waters, as soil waters were enriched in highly unsaturated oxygen-rich compounds (typical for vascular plants), which were much less abundant in drip waters. Conversely, peptides, which can originate from bacterial processes, were present only in the drip waters. Our data clearly show connectivity between the cave and overlaying soils, and reworking of DOM by the cave bacterial community. Furthermore, we found molecular evidence for the selective removal of vascular plant-derived DOM in the caves, possibly due to abiotic interactions with minerals.

  19. Structural characterization of lignin: a potential source of antioxidants guaiacol and 4-vinylguaiacol.

    Science.gov (United States)

    Azadfar, Mohammadali; Gao, Allan Haiming; Bule, Mahesh V; Chen, Shulin

    2015-04-01

    The structure of lignin obtained from the ozone and soaking aqueous ammonia pretreatment of wheat straw has been characterized utilizing chemical analytical methods in order to reveal its antioxidant characteristics, including attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), pyrolysis/tetramethylammonium hydroxide-gas chromatography/mass spectrometry (Py/TMAH-GC/MS), gel permeation chromatography (GPC), ultra violet-visible spectroscopy (UV-vis), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) antioxidant evaluation assay. The results demonstrated that the isolated lignin is a ρ-hydroxyphenyl- guaiacyl-syringyl (H-G-S) lignin, with S/G ratio of 0.35 and significant amounts of phenol 2-methoxy (guaiacol) and phenol 2-methoxy-4-vinyl (4-vinylguaiacol). The Py-GC/MS and Py/TMAH-GC/MS pyrograms indicated that the major units in this lignin are derived from hydroxycinnamic acids. The GPC results revealed the molecular weight of the lignin was considerably low and also the FTIR analysis showed that the lignin possessed hydroxyl and methoxy functional groups; the factors led to the extracted lignin having a comparable antioxidant activity to that of currently used commercial antioxidants. The UV-vis and DPPH antioxidant assay results suggested a percentage of inhibition of the DPPH radicals in the following order: guaiacol (103.6 ± 1.36)>butylated hydroxytoluene (103.3 ± 1)>ferulic acid (102.6 ± 0.79)>pretreated lignin (86.9 ± 0.34). PMID:25603142

  20. Preparation and characterization of cesium-137 aluminosilicate pellets for radioactive source applications

    International Nuclear Information System (INIS)

    Twenty-seven fully loaded 137Cs aluminosilicate pellets were fabricated in a hot cell by the vacuum hot pressing of a cesium carbonate/montmorillonite clay mixture at 15000C and 570 psig. Four pellets were selected for characterization studies which included calorimetric measurements, metallography, scanning electron microscope and electron backscattering (SEM-BSE), electron microprobe, x-ray diffraction, and cesium ion leachability measurements. Each test pellet contained 437 to 450 curies of 137Cs as determined by calorimetric measurements. Metallographic examinations revealed a two-phase system: a primary, granular, gray matrix phase containing large and small pores and small pore agglomerations, and a secondary fused phase interspersed throughout the gray matrix. SEM-BSE analyses showed that cesium and silicon were uniformly distributed throughout both phases of the pellet. This indicated that the cesium-silicon-clay reaction went to completion. Aluminum homogeneity was unconfirmed due to the high background noise associated with the inherent radioactivity of the test specimens. X-ray diffraction analyses of both radioactive and non-radioactive aluminosilicate pellets confirmed the crystal lattice structure to be pollucite. Cesium ion quasistatic leachability measurements determined the leach rates of fully loaded 137Cs sectioned pollucite pellets to date to be 4.61 to 34.4 x 10-10 kg m-2s-1, while static leach tests performed on unsectioned fully loaded pellets showed the leach rates of the cesium ion to date to be 2.25 to 3.41 x 10-12 kg m-2s-1. The cesium ion diffusion coefficients through the pollucite pellet were calculated using Fick's first and second laws of diffusion. The diffusion coefficients calculated for three tracer level 137Cs aluminosilicate pellets were 1.29 x 10-16m2s-1, 6.88 x 10-17m2s-1, and 1.35 x 10-17m2s-1, respectively

  1. Characterization of the indoor particles and their sources in an Antarctic research station.

    Science.gov (United States)

    Pagel, Érica Coelho; Costa Reis, Neyval; de Alvarez, Cristina Engel; Santos, Jane Méri; Conti, Melina Moreira; Boldrini, Ricardo Salvador; Kerr, Américo Sansigolo

    2016-03-01

    Many studies have been carried out on the environmental impact of the research stations on the Antarctic continent. However, the assessment of indoor air quality in these confined environments has been neglected. The main objectives of this study are to investigate the granulometric distribution of the indoor particles in the different compartments of the Brazilian Antarctic Station, to examine the number and mass concentration of the indoor particles, to conduct chemical and morphological analyses of the indoor PM2.5, and to identify the possible sources of the PM. The results showed that Na, K, Cl, Fe, Zn, S and Si were the main elements detected. High levels of black carbon were recorded in the workshop, which may be associated with the use of diesel vehicles. To identify the human activities related to the indoor particle emission in the station, the size distribution of the particles in the living room was monitored for seven consecutive days, during normal station operation. It was possible to identify the influence of individual processes, such as incineration, cooking and the movement of people, upon the particle size number concentration. The indoor/outdoor (I/O) ratio for the total suspended particles (TSP), PM10, PM2.5 and PM1 measured was significantly larger than those reported for urban buildings. In general, the I/O ratio distribution for all the compartments shows peak values between 2.5 and 10 μm, which is often related to human activity, such as cleaning, personnel circulation or clothing surfaces. The maximum I/O ratio at this range varied from 12 to 60. In addition, the compartments affected by combustion processes tend to present a significant number of submicron particles. PMID:26884354

  2. Process-based characterization of evapotranspiration sources over the North American monsoon region

    Science.gov (United States)

    Bohn, Theodore J.; Vivoni, Enrique R.

    2016-01-01

    Evapotranspiration (ET) is a poorly constrained flux in the North American monsoon (NAM) region, leading to potential errors in land-atmosphere feedbacks. We quantified the spatiotemporal variations of ET using the Variable Infiltration Capacity (VIC) model, modified to account for soil evaporation (Esoil), irrigated agriculture, and the variability of land surface properties derived from the Moderate Resolution Imaging Spectroradiometer during 2000-2012. Simulated ET patterns were compared to field observations at 59 eddy covariance towers, water balance estimates in nine basins, and six available gridded ET products. The modified VIC model performed well at eddy covariance towers representing the natural and agricultural land covers in the region. Simulations revealed that major sources of ET were forested mountain areas during the summer season and irrigated croplands at peak times of growth in the winter and summer, accounting for 22% and 9% of the annual ET, respectively. Over the NAM region, Esoil was the largest component (60%) of annual ET, followed by plant transpiration (T, 32%) and evaporation of canopy interception (8%). Esoil and T displayed different relationships with P in natural land covers, with Esoil tending to peak earlier than T by up to 1 month, while only a weak correlation between ET and P was found in irrigated croplands. Based on the model performance, the VIC-based estimates are the most realistic to date for this region. Furthermore, spatiotemporal patterns reveal new information on the magnitudes, locations, and timing of ET in the North American monsoon region with implications on land-atmosphere feedbacks.

  3. Characterization of the indoor particles and their sources in an Antarctic research station.

    Science.gov (United States)

    Pagel, Érica Coelho; Costa Reis, Neyval; de Alvarez, Cristina Engel; Santos, Jane Méri; Conti, Melina Moreira; Boldrini, Ricardo Salvador; Kerr, Américo Sansigolo

    2016-03-01

    Many studies have been carried out on the environmental impact of the research stations on the Antarctic continent. However, the assessment of indoor air quality in these confined environments has been neglected. The main objectives of this study are to investigate the granulometric distribution of the indoor particles in the different compartments of the Brazilian Antarctic Station, to examine the number and mass concentration of the indoor particles, to conduct chemical and morphological analyses of the indoor PM2.5, and to identify the possible sources of the PM. The results showed that Na, K, Cl, Fe, Zn, S and Si were the main elements detected. High levels of black carbon were recorded in the workshop, which may be associated with the use of diesel vehicles. To identify the human activities related to the indoor particle emission in the station, the size distribution of the particles in the living room was monitored for seven consecutive days, during normal station operation. It was possible to identify the influence of individual processes, such as incineration, cooking and the movement of people, upon the particle size number concentration. The indoor/outdoor (I/O) ratio for the total suspended particles (TSP), PM10, PM2.5 and PM1 measured was significantly larger than those reported for urban buildings. In general, the I/O ratio distribution for all the compartments shows peak values between 2.5 and 10 μm, which is often related to human activity, such as cleaning, personnel circulation or clothing surfaces. The maximum I/O ratio at this range varied from 12 to 60. In addition, the compartments affected by combustion processes tend to present a significant number of submicron particles.

  4. Extent, characterization, and sources of soil lead contamination in small-urban residential neighborhoods.

    Science.gov (United States)

    Clark, Jeffrey J; Knudsen, Andrew C

    2013-09-01

    We present high spatial-resolution mapping of soil lead (Pb) concentrations in a small-urban residential setting. X-ray fluorescence was used to measure soil Pb at170 properties in the City Park neighborhood of Appleton, Wisconsin. Greater than two-thirds of soil samples collected from drip lines contained more than 400 μg g of Pb, and one third exceeded 1200 μg g. Soils adjacent to homes built before 1960 contained significantly higher Pb levels than those near younger homes. Three front yard locations (drip line, mid-yard, and terrace) were sampled at 71 properties. A general decline in soil Pb with increasing distance from the house was observed. Detailed sampling of individual homes within a single residential block revealed Pb-contaminated soil radiating outward from homes in all directions, creating a "bulls-eye" pattern. Approximately 40% of yard space exceeded concentrations of 400 μg g. These patterns of contamination are consistent with Pb paint as the main contributor of Pb to soil. This has important implications because spatial distribution of Pb contamination is fundamentally different if paint, rather than automobile exhaust, is the primary source. Selective sequential extraction analyses suggest that roughly half of the soil Pb resides in chemically reactive and bioavailable phases. The extent and persistence of soil Pb, the resurgence of home gardening, and the serious health consequences of Pb ingestion argue for attention to this problem, not just in dense urban centers but also in smaller urban settings across the country. PMID:24216427

  5. Starch films from a novel (Pachyrhizus ahipa) and conventional sources: Development and characterization

    International Nuclear Information System (INIS)

    Biodegradable films from ahipa, cassava and corn native starches were developed by casting method and their physicochemical, mechanical and barrier properties were analyzed taking into account the different starch botanical sources. Filmogenic suspensions were prepared; their rheological behaviors were studied and all of them exhibited film-forming ability. However, mechanical assays demonstrated that unplasticized films were too rigid, limiting their technological applications. Thus, 1.5% w/w of glycerol as plasticizer was added to filmogenic suspensions and film flexibility and extensibility were improved, this effect was more significant for ahipa and cassava starch films. Furthermore, thickness, moisture content and water solubility of the developed films were increased when plasticizer was incorporated. Glycerol addition reduced film water vapor permeability and the lowest reduction corresponded to cassava starch films due to the high viscosity of its filmogenic suspensions. Plasticized starch films resulted to be UV radiation barriers; ahipa starch films had the lowest light absorption capacity and higher transparency than cassava and corn starch films. Dynamic-mechanical analysis indicated that plasticized films were partially miscible systems exhibiting two relaxations, one attributed to the starch-rich phase and the other to the glycerol-rich one. Likewise, it could be demonstrated that glycerol exerted a major plasticizing effect on ahipa starch matrixes. Highlights: ► Ahipa, cassava and corn starch films were developed by casting method. ► Glycerol effect on film mechanical behavior was major for tuberous starch films. ► Ahipa starch films resulted to be more transparent with lower UV absorption capacity. ► Plasticized films were partially miscible systems: with a glycerol-rich and a starch-rich phase. ► Glycerol exerted a major plasticizing effect on ahipa starch films.

  6. Regional land cover characterization using Landsat thematic mapper data and ancillary data sources

    Science.gov (United States)

    Vogelmann, J.E.; Sohl, T.L.; Campbell, P.V.; Shaw, D.M.; ,

    1998-01-01

    As part of the activities of the Multi-Resolution Land Characteristics (MRLC) Interagency Consortium, an intermediate-scale land cover data set is being generated for the conterminous United States. This effort is being conducted on a region-by-region basis using U.S. Standard Federal Regions. To date, land cover data sets have been generated for Federal Regions 3 (Pennsylvania, West Virginia, Virginia, Maryland, and Delaware) and 2 (New York and New Jersey). Classification work is currently under way in Federal Region 4 (the southeastern United States), and land cover mapping activities have been started in Federal Regions 5 (the Great Lakes region) and 1 (New England). it is anticipated that a land cover data set for the conterminous United States will be completed by the end of 1999. A standard land cover classification legend is used, which is analogous to and compatible with other classification schemes. The primary MRLC regional classification scheme contains 23 land cover classes. The primary source of data for the project is the Landsat thematic mapper (TM) sensor. For each region, TM scenes representing both leaf-on and leaf-off conditions are acquired, preprocessed, and georeferenced to MRLC specifications. Mosaicked data are clustered using unsupervised classification, and individual clusters are labeled using aerial photographs. Individual clusters that represent more than one land cover unit are split using spatial modeling with multiple ancillary spatial data layers (most notably, digital elevation model, population, land use and land cover, and wetlands information). This approach yields regional land cover information suitable for a wide array of applications, including landscape metric analyses, land management, land cover change studies, and nutrient and pesticide runoff modeling.

  7. Starch films from a novel (Pachyrhizus ahipa) and conventional sources: Development and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, Olivia V., E-mail: ovlopez75@yahoo.com.ar; Garcia, Maria A.

    2012-10-01

    Biodegradable films from ahipa, cassava and corn native starches were developed by casting method and their physicochemical, mechanical and barrier properties were analyzed taking into account the different starch botanical sources. Filmogenic suspensions were prepared; their rheological behaviors were studied and all of them exhibited film-forming ability. However, mechanical assays demonstrated that unplasticized films were too rigid, limiting their technological applications. Thus, 1.5% w/w of glycerol as plasticizer was added to filmogenic suspensions and film flexibility and extensibility were improved, this effect was more significant for ahipa and cassava starch films. Furthermore, thickness, moisture content and water solubility of the developed films were increased when plasticizer was incorporated. Glycerol addition reduced film water vapor permeability and the lowest reduction corresponded to cassava starch films due to the high viscosity of its filmogenic suspensions. Plasticized starch films resulted to be UV radiation barriers; ahipa starch films had the lowest light absorption capacity and higher transparency than cassava and corn starch films. Dynamic-mechanical analysis indicated that plasticized films were partially miscible systems exhibiting two relaxations, one attributed to the starch-rich phase and the other to the glycerol-rich one. Likewise, it could be demonstrated that glycerol exerted a major plasticizing effect on ahipa starch matrixes. Highlights: Black-Right-Pointing-Pointer Ahipa, cassava and corn starch films were developed by casting method. Black-Right-Pointing-Pointer Glycerol effect on film mechanical behavior was major for tuberous starch films. Black-Right-Pointing-Pointer Ahipa starch films resulted to be more transparent with lower UV absorption capacity. Black-Right-Pointing-Pointer Plasticized films were partially miscible systems: with a glycerol-rich and a starch-rich phase. Black-Right-Pointing-Pointer Glycerol exerted

  8. Final report of the IAEA advisory group meeting on accelerator-based nuclear analytical techniques for characterization and source identification of aerosol particles

    International Nuclear Information System (INIS)

    The field of aerosol characterization and source identification covers a wide range of scientific and technical activities in many institutions, in both developed and developing countries. This field includes research and applications on urban air pollution, source apportionment of suspended particulate matter, radioactive aerosol particles, organic compounds carried on particulate matter, elemental characterization of particles, and other areas. The subject of this AGM focused on the use of accelerator-based nuclear analytical techniques for determination of elemental composition of particles (by either bulk or single particle analysis) and the use of accumulated knowledge for source identification

  9. Radioactive particles in the environment: sources, particle characterization and analytical techniques

    International Nuclear Information System (INIS)

    Over the years, radioactive particles have been released to the environment from nuclear weapons testing and nuclear fuel cycle operations. However, measurements of environmental radioactivity and any associated assessments are often based on the average bulk mass or surface concentration, assuming that radionuclides are homogeneously distributed as simple ionic species. It has generally not been recognised that radioactive particles present in the environment often contain a significant fraction of the bulk sample activity, leading to sample heterogeneity problems and false and/or erratic measurement data. Moreover, the inherent differences in the transport and bioavailability of particle bound radionuclides compared with those existing as molecules or ions have largely been ignored in dose assessments. To date, most studies regarding radionuclide behaviour in the soil-plant system have dealt with soluble forms of radionuclides. When radionuclides are deposited in a less mobile form, or in case of a superposition of different physico-chemical forms, the behaviour of radionuclides becomes much more complicated and extra efforts are required to provide information about environmental status and behaviour of radioactive particles. There are currently no documents or international guides covering this aspect of environmental impact assessments. To fill this gap, between 2001 and 2008 the IAEA performed a Coordinated Research Programme (CRP- G4.10.03) on the 'Radiochemical, Chemical and Physical Characterization of Radioactive Particles in the Environment' with the objective of development, adoption and application of standardized analytical techniques for the comprehensive study of radioactive particles. The CRP was in line with the IAEA project intended to assist the Member States in building capacity for improving environmental assessments and for management of sites contaminated with radioactive particles. This IAEA-TECDOC presents the findings and achievements of

  10. Preparation and characterization of cesium-137 aluminosilicate pellets for radioactive source applications

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, F.J.; Tompkins, J.A.; Haff, K.W.; Case, F.N.

    1981-07-01

    Twenty-seven fully loaded /sup 137/Cs aluminosilicate pellets were fabricated in a hot cell by the vacuum hot pressing of a cesium carbonate/montmorillonite clay mixture at 1500/sup 0/C and 570 psig. Four pellets were selected for characterization studies which included calorimetric measurements, metallography, scanning electron microscope and electron backscattering (SEM-BSE), electron microprobe, x-ray diffraction, and cesium ion leachability measurements. Each test pellet contained 437 to 450 curies of /sup 137/Cs as determined by calorimetric measurements. Metallographic examinations revealed a two-phase system: a primary, granular, gray matrix phase containing large and small pores and small pore agglomerations, and a secondary fused phase interspersed throughout the gray matrix. SEM-BSE analyses showed that cesium and silicon were uniformly distributed throughout both phases of the pellet. This indicated that the cesium-silicon-clay reaction went to completion. Aluminum homogeneity was unconfirmed due to the high background noise associated with the inherent radioactivity of the test specimens. X-ray diffraction analyses of both radioactive and non-radioactive aluminosilicate pellets confirmed the crystal lattice structure to be pollucite. Cesium ion quasistatic leachability measurements determined the leach rates of fully loaded /sup 137/Cs sectioned pollucite pellets to date to be 4.61 to 34.4 x 10/sup -10/ kg m/sup -2/s/sup -1/, while static leach tests performed on unsectioned fully loaded pellets showed the leach rates of the cesium ion to date to be 2.25 to 3.41 x 10/sup -12/ kg m/sup -2/s/sup -1/. The cesium ion diffusion coefficients through the pollucite pellet were calculated using Fick's first and second laws of diffusion. The diffusion coefficients calculated for three tracer level /sup 137/Cs aluminosilicate pellets were 1.29 x 10/sup -16/m/sup 2/s/sup -1/, 6.88 x 10/sup -17/m/sup 2/s/sup -1/, and 1.35 x 10/sup -17/m/sup 2/s/sup -1

  11. Aerosol composition, chemistry, and source characterization during the 2008 VOCALS Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y.; Springston, S.; Jayne, J.; Wang, J.; Senum, G.; Hubbe, J.; Alexander, L.; Brioude, J.; Spak, S.; Mena-Carrasco, M.; Kleinman, L.; Daum, P.

    2010-03-15

    Chemical composition of fine aerosol particles over the northern Chilean coastal waters was determined onboard the U.S. DOE G-1 aircraft during the VOCALS (VAMOS Ocean-Cloud-Atmosphere-Land Study) field campaign between October 16 and November 15, 2008. SO42-, NO3-, NH4+, and total organics (Org) were determined using an Aerodyne Aerosol Mass Spectrometer, and SO42-, NO3-, NH4+, Na+, Cl-, CH3SO3-, Mg2+, Ca2+, and K+ were determined using a particle-into-liquid sampler-ion chromatography technique. The results show the marine boundary layer (MBL) aerosol mass was dominated by non- sea-salt SO42- followed by Na+, Cl-, Org, NO3-, and NH4+, in decreasing importance; CH3SO3-, Ca2+, and K+ rarely exceeded their respective limits of detection. The SO42- aerosols were strongly acidic as the equivalent NH4+ to SO42- ratio was only {approx}0.25 on average. NaCl particles, presumably of sea-salt origin, showed chloride deficits but retained Cl- typically more than half the equivalency of Na+, and are externally mixed with the acidic sulfate aerosols. Nitrate was observed only on sea-salt particles, consistent with adsorption of HNO3 on sea-salt aerosols, responsible for the Cl- deficit. Dust particles appeared to play a minor role, judging from the small volume differences between that derived from the observed mass concentrations and that calculated based on particle size distributions. Because SO42- concentrations were substantial ({approx}0.5 - {approx}3 {micro}g/m3) with a strong gradient (highest near the shore), and the ocean-emitted dimethylsulfide and its unique oxidation product, CH3SO3-, were very low (i.e., {le} 40 parts per trillion and <0.05 {micro}g/m3, respectively), the observed SO42- aerosols are believed to be primarily of terrestrial origin. Back trajectory calculations indicate sulfur emissions from smelters and power plants along coastal regions of Peru and Chile are the main sources of these SO4- aerosols. However, compared to observations, model

  12. Wildfire smoke in the Siberian Arctic in summer: source characterization and plume evolution from airborne measurements

    Directory of Open Access Journals (Sweden)

    P. Ciais

    2009-12-01

    Full Text Available We present airborne measurements of carbon dioxide (CO2, carbon monoxide (CO, ozone (O3, equivalent black carbon (EBC and ultra fine particles over North-Eastern Siberia in July 2008 performed during the YAK-AEROSIB/POLARCAT experiment. During a "golden day" (11 July 2008 a number of biomass burning plumes were encountered with CO mixing ratio enhancements of up to 500 ppb relative to a background of 90 ppb. Number concentrations of aerosols in the size range 3.5–200 nm peaked at 4000 cm−3 and the EBC content reached 1.4 μg m−3. These high concentrations were caused by forest fires in the vicinity of the landing airport in Yakutsk where measurements in fresh smoke could be made during the descent. We estimate a combustion efficiency of 90 ± 3% based on CO and CO2 measurements and a CO emission factor of 65.5 ± 10.8 g CO per kilogram of dry matter burned. This suggests a potential increase in the average northern hemispheric CO mixing ratio of 3.0–7.2 ppb per million hectares of Siberian forest burned. For BC, we estimate an emission factor of 0.52 ± 0.07 g BC kg−1, comparable to values reported in the literature. The emission ratio of ultra-fine particles (3.5–200 nm was 26 cm−3 (ppb CO−1, consistent with other airborne studies.

    The transport of identified biomass burning plumes was investigated using the FLEXPART Lagrangian model. Based on sampling of wildfire plumes from the same source but with different atmospheric ages derived from FLEXPART, we estimate that the e-folding lifetimes of EBC and ultra fine particles (between 3.5 and 200 nm in size against removal and growth processes are 5.1 and 5.5 days respectively, supporting lifetime estimates used in various modelling studies.

  13. Three-dimensional vortex analysis and aeroacoustic source characterization of jet core breakdown

    Science.gov (United States)

    Violato, Daniele; Scarano, Fulvio

    2013-01-01

    The three-dimensional behavior of jet core breakdown is investigated with experiments conducted on a free water jet at Re = 5000 by time-resolved tomographic particle image velocimetry (TR-TOMO PIV). The investigated domain encompasses the range between 0 and 10 jet diameters. The characteristic pulsatile motion of vortex ring shedding and pairing culminates with the growth of four primary in-plane and out-of-plane azimuthal waves and leads to the formation of streamwise vortices. Vortex ring humps are tilted and ejected along the axial direction as they are subjected to higher axial velocities. By the end of the potential core, this process causes the breakdown of the vortex ring regime and the onset of streamwise filaments oriented at 30°-45° to the jet axis and "C" shaped peripheral structures. The latter re-organize further downstream in filaments oriented along the azimuthal direction at the jet periphery. Instead, in the vicinity of the jet axis the filaments do not exhibit any preferential direction resembling the isotropic turbulent regime. Following Powell's aeroacoustic analogy, the instantaneous spatial distribution of the acoustic source term is mapped by the second time derivative of the Lamb vector, revealing the highest activity during vortex ring breakdown. A three-dimensional modal analysis of velocity, vorticity, Lamb vector, and Lamb vector second time derivative fields is conducted by proper orthogonal decomposition (POD) within the first 10 modes. The decomposed velocity fluctuations describe a helical organization in the region of the jet core-breakdown and, further downstream, jet axis flapping and precession motions. By the end of the potential core, vorticity modes show that vortex rings are dominated by travelling waves of radial and axial vorticity with a characteristic 40°-45° inclination to the jet axis. The Lamb vector and the Lamb vector second time derivative modes exhibit similar patterns for the azimuthal component, whereas the

  14. Aerosol Composition, Chemistry, and Source Characterization during the 2008 VOCALS Experiment

    Science.gov (United States)

    Lee, Y.; Springston, S.; Jayne, J. T.; Wang, J.; Senum, G.; Hubbe, J.; Alexander, L.; Brioude, J.; Spak, S.; Mena-Carrasco, M.; Kleinman, L. I.; Daum, P. H.

    2009-12-01

    Chemical composition of fine aerosol particles over the northern Chilean coastal waters was determined on board the US DOE G-1 aircraft during the VOCALS (VAMOS Ocean-Cloud-Atmosphere-Land Study) field experiment between October 16 and November 15, 2008. Chemical species determined included SO42-, NO3-, NH4+, and total organics (Org) using an Aerodyne Aerosol Mass Spectrometer, and SO42-, NO3-, NH4+, Na+, Cl-, CH3SO3-, Mg2+, Ca2+, and K+ using a particle-into-liquid sampler-ion chromatography technique. The results show the marine boundary layer (MBL) aerosol mass was dominated by non-sea-salt SO42- followed by Na+, Cl-, Org, NO3-, and NH4+, in decreasing importance; CH3SO3-, Ca2+, and K+ rarely exceeded their respective limits of detection. The SO42- aerosols were strongly acidic as the equivalent NH4+ to SO42- ratio was only ~0.25 on average. NaCl particles, presumably of sea-salt origin, showed chloride deficits but retained Cl- typically more than half the equivalency of Na+, and are believed to be externally mixed with the acidic sulfate aerosols. Nitrate was observed only on sea-salt particles, consistent with adsorption of HNO3 on non-acidic sea-salt aerosols, responsible partly for the Cl- deficit. Dust particles appeared to play a minor role judging from the small volume differences between that derived from the observed mass concentrations and that calculated based on particle size distributions. Because SO42- concentrations in the study domain were substantial (~0.5 - ~3 μg/m3) with a strong gradient (highest near the shore decreasing with distance from land), and the ocean-emitted dimethylsulfide and its unique oxidation product, CH3SO3-, were very low (i.e., ≤ 40 parts per trillion and power plants along coastal regions of Peru and Chile are the main sources of these SO4- aerosols. However, compared to observations, model calculations appeared to underestimate sulfate concentrations based on an existing emission inventory. An up-to-date and

  15. Noise characterization of silicon strip detectors-comparison of sensors with and without integrated jfet source-follower.

    CERN Document Server

    Giacomini, Gabriele

    Noise is often the main factor limiting the performance of detector systems. In this work a detailed study of the noise contributions in different types of silicon microstrip sensors is carried on. We investigate three sensors with double-sided readout fabricated by different suppliers for the ALICE experiment at the CERN LHC, in addition to detectors including an integrated JFET Source-Follower as a first signal conditioning stage. The latter have been designed as an attempt at improving the performance when very long strips, obtained by gangling together several sensors, are required. After a description of the strip sensors and of their operation, the “static” characterization measurements performed on them (current and capacitance versus voltage and/or frequency) are illustrated and interpreted. Numerical device simulation has been employed as an aid in interpreting some of the measurement results. The commonly used models for expressing the noise of the detector-amplifier system in terms of its relev...

  16. Electron cyclotron resonance ion source plasma characterization by X-ray spectroscopy and X-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mascali, David, E-mail: davidmascali@lns.infn.it; Castro, Giuseppe; Celona, Luigi; Neri, Lorenzo; Gammino, Santo [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Biri, Sándor; Rácz, Richárd; Pálinkás, József [Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/c, H-4026 Debrecen (Hungary); Caliri, Claudia [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Università degli Studi di Catania, Dip.to di Fisica e Astronomia, via Santa Sofia 64, 95123 Catania (Italy); Romano, Francesco Paolo [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); CNR, Istituto per i Beni Archeologici e Monumentali, Via Biblioteca 4, 95124 Catania (Italy); Torrisi, Giuseppe [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Università Mediterranea di Reggio Calabria, DIIES, Via Graziella, I-89100 Reggio Calabria (Italy)

    2016-02-15

    An experimental campaign aiming to investigate electron cyclotron resonance (ECR) plasma X-ray emission has been recently carried out at the ECRISs—Electron Cyclotron Resonance Ion Sources laboratory of Atomki based on a collaboration between the Debrecen and Catania ECR teams. In a first series, the X-ray spectroscopy was performed through silicon drift detectors and high purity germanium detectors, characterizing the volumetric plasma emission. The on-purpose developed collimation system was suitable for direct plasma density evaluation, performed “on-line” during beam extraction and charge state distribution characterization. A campaign for correlating the plasma density and temperature with the output charge states and the beam intensity for different pumping wave frequencies, different magnetic field profiles, and single-gas/gas-mixing configurations was carried out. The results reveal a surprisingly very good agreement between warm-electron density fluctuations, output beam currents, and the calculated electromagnetic modal density of the plasma chamber. A charge-coupled device camera coupled to a small pin-hole allowing X-ray imaging was installed and numerous X-ray photos were taken in order to study the peculiarities of the ECRIS plasma structure.

  17. Synthesis and characterization of nanocrystalline nickel oxide using NaOH and oxalic acid as oxide sources

    International Nuclear Information System (INIS)

    Precursors of nickel oxide (NiO) nanoparticles were synthesized through a simple chemical precipitation method by changing the oxide source used for the synthesis. The synthesized precursors were subjected to thermo gravimetric analysis (TGA) to determine the temperature at which the precursors decompose into nickel oxide. The obtained results of TGA suggest that precursor NiO prepared using sodium hydroxide (NaOH) showed NiO formation at 600 °C, whereas, when oxalic acid was used as oxide source the formation of NiO took place at 400 °C. After calcinations of the precursors at respective temperatures, NiO nanocrystals have been harvested. The synthesized NiO powders were characterized by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), photoluminescence (PL) spectroscopy, field emission scanning electron microscopy (FE-SEM), energy dispersive x-ray analysis (EDX), and vibrating sample magnetometer (VSM) analysis. An FE-TEM image of NiO prepared using oxalic acid showed spherical and elliptical particles with sizes in the range of 15 nm. The Williamson–Hall (W–H) plots were drawn for the annealed products to study their lattice strain and crystallite size. The sizes of NiO nanocrystals obtained from W–H analysis are well correlated with sizes estimated using Scherrer’s formula. The relatively low saturation magnetization of NiO confirms its super paramagnetic behavior. (papers)

  18. The PM10 fraction of road dust in the UK and India: Characterization, source profiles and oxidative potential.

    Science.gov (United States)

    Pant, Pallavi; Baker, Stephen J; Shukla, Anuradha; Maikawa, Caitlin; Godri Pollitt, Krystal J; Harrison, Roy M

    2015-10-15

    Most studies of road dust composition have sampled a very wide range of particle sizes, but from the perspective of respiratory exposure to resuspended dusts, it is the PM10 fraction which is of most importance. The PM10 fraction of road dust samples was collected at two sites in Birmingham, UK (major highway and road tunnel) and one site in New Delhi, India. Dust loadings were found to be much higher for New Delhi compared to Birmingham, while concentrations of several species were much higher in the case of Birmingham. Detailed chemical source profiles were prepared for both cities and previously generated empirical factors for source attribution to brake wear, tyre wear, and crustal dust were successfully applied to the UK sites. However, 100% of the mass for the Indian site could not be accounted for using these factors. This study highlights the need for generation of local empirical estimation factors for non-exhaust vehicle emissions. A limited number of bulk road dust and brake pad samples were also characterized. Oxidative potential (OP) was also determined for a limited number of PM10 and bulk road dust samples, and Cu was found to be a factor significantly associated with OP in PM10 and bulk road dust. PMID:26033216

  19. Investigation of discharge-area groundwaters for recharge source characterization on different scales: the case of Jinan in northern China

    Science.gov (United States)

    Wang, Jiale; Jin, Menggui; Lu, Guoping; Zhang, Dele; Kang, Fengxin; Jia, Baojie

    2016-05-01

    Discharge-area groundwater in Jinan, a typical karst region in northern China, was investigated by studying both the hydrological and chemical processes evolving from the recharge in mountainous terrains to the karst-spring outflows in the metropolitan area. Large-scale exploitation of karst groundwater has led to a disturbing trend in the ever-decreasing spring outflow rates and groundwater level. There is insufficient information about the Jinan karst aquifers, which provide the main water sources to meet human demand and to sustain spring outflow. The coupling of hydrological and chemical processes quantifies the flow system through aqueous chemistry characterization of the water sources. This approach is used to study the groundwater flow discharges in different locations and geological settings. The potentiometric data indicated limited vertical connectivity between distinct hydrogeological units and alteration of the recharge regime by the faults and by artificial exploitation. Shallow groundwater primarily belongs to the local flow system, with high nitrate concentration and enriched stable isotopic contents. Thermal groundwater has high concentrations of chloride and total dissolved solids, derived from a regional flow system with the highest recharge altitudes and long residence time. Non-thermal karst water may be attributed to the intermediate flow system, with uniform HCO3-Ca(Mg) facies and low nitrate concentration. This work highlighted discharge as a fingerprint of groundwater flow conditions and provides a better insight into the hydrogeological system.

  20. Characterization, Distribution, Sources and Origins of Aliphatic Hydrocarbons from Surface Sediment of Prai Strait, Penang, Malaysia: A Widespread Anthropogenic Input

    Directory of Open Access Journals (Sweden)

    Mahyar Sakari

    2008-07-01

    Full Text Available Persistent organic pollutants such as petroleum hydrocarbons are one of the most serious and important class of pollutants that face to many countries including Malaysia. Aliphatic hydrocarbons contain straight chain alkane; derive from anthropogenic and natural sources to the marine environment. The multi-purpose strait of Prai is located in the Northwest of Peninsular Malaysia plays an important economic role in the Southeast Asia. Twenty surface sediment samples were collected using Eckman dredge to measure the concentration and determine the characterization, sources and origins of the aliphatic hydrocarbons in December 2006. Samples (top 4 cm were extracted with Soxhlet, treated with activated copper and subjected to 2 steps column chromatography for purification and fractionation. Alkane fraction injected into Gas Chromatography–Flame Ionization Detector (GC-FID for instrumental analysis. The results showed that total n-alkane concentrations are ranging from 512 to 10770 ng/mg d. w. Carbon Preferences Index (CPI revealed an extreme widespread anthropogenic input and naturally derived (CPI= 0 to 4.88 hydrocarbons in the study area. The ratio of C31/C19 indicated that natural hydrocarbons are generating from terrestrial vascular plants and transferring by rivers. The characteristics of Major Hydrocarbons provided evidences that oil and its derivatives either fresh or degraded are the major contributors of the pollution in the study area. Statistical approaches also confirmed that 85% of study area affected by oil sources of pollution. It is seen that aliphatic hydrocarbons mostly transfer by lateral input to the marine environment than atmospheric movements.

  1. Characterization of neutron flux spectra in the irradiation sites of a 37 GBq {sup 241}Am-Be isotopic source

    Energy Technology Data Exchange (ETDEWEB)

    Yücel, Haluk [Ankara University, Institute of Nuclear Sciences, 06100 Tandogan, Ankara (Turkey); Budak, Mustafa Guray, E-mail: mbudak@gazi.edu.tr [Gazi University, Gazi Education Faculty, 06500 Teknikokullar, Ankara (Turkey); Karadag, Mustafa [Gazi University, Gazi Education Faculty, 06500 Teknikokullar, Ankara (Turkey); Yüksel, Alptuğ Özer [Ankara University, Institute of Nuclear Sciences, 06100 Tandogan, Ankara (Turkey)

    2014-11-01

    Highlights: • An irradiation unit was installed using a 37 GBq {sup 241}Am-Be neutron source. • The source neutrons moderated by using both water and paraffin. • Irradiation unit was shielded by boron oxide and lead against neutrons and gammas. • There are two sites for irradiations, one of them has a pneumatic transfer system. • Cadmium ratio method was used for irradiation site characterization. - Abstract: For the applicability of instrumental neutron activation analysis (NAA) technique, an irradiation unit with a 37 GBq {sup 241}Am-Be neutron source was installed at Institute of Nuclear Sciences of Ankara University. Design and configuration properties of the irradiation unit are described. It has two different sample irradiation positions, one is called site #1 having a pneumatic sample transfer system and the other is site #2 having a location for manual use. In order to characterize neutron flux spectra in the irradiation sites, the measurement results were obtained for thermal (φ{sub th}) and epithermal neutron fluxes (φ{sub epi}), thermal to epithermal flux ratio (f) and epithermal spectrum shaping factors (α) by employing cadmium ratios of gold (Au) and molybdenum (Mo) monitors. The activities produced in these foils were measured by using a p-type, 44.8% relative efficiency HPGe well detector. For the measured γ-rays, self-absorption and true coincidence summing effects were taken into account. Additionally, thermal neutron self-shielding and resonance neutron self-shielding effects were taken into account in the measured results. For characterization of site #1, the required parameters were found to be φ{sub th} = (2.11 ± 0.05) × 10{sup 3} n cm{sup −2} s{sup −1}, φ{sub epi} = (3.32 ± 0.17) × 10{sup 1} n cm{sup −2} s{sup −1}, f = 63.6 ± 1.5, α = 0.045 ± 0.009, respectively. Similarly, those parameters were measured in site #2 as φ{sub th} = (1.49 ± 0.04) × 10{sup 3} n cm{sup −2} s{sup −1}, φ{sub epi} = (2.93 ± 0

  2. A hydrogeochemical study of rain water to characterize the source of atmospheric pollutants at Jodhpur - desert city of India (abstract)

    International Nuclear Information System (INIS)

    A study was undertaken has been conducted to determined the physical parameters and chemical species in the first precipitants of the season at desert city of Jodhpur to understand firstly, the degree of pollutants in the atmosphere and secondly to identity the minerals/pollutants of the atmosphere to characterize its possible source of origin. The precipitate samples for cations and other physical and chemical parameters by standard analytical methods. The results obtained on turbidity, conductivity, total dissolved solids and the ratio of total dissolved solids and conductivity, show a moderate degree of pollutants at all the four sites, A, B, C and D but slightly higher at C and D sites. The concentration of various water-soluble chemical species present in the precipitates, specially a balance between acidic and basic constituents decides its pH value. Hydrogen ions are mainly responsible for acidification of rain waters and are derived chiefly from oxidation of SO/sub 2/ and NO/sub 2/ to from H/sub 2/SO/sub 4/ and HNO/sub 3/ respectively. Hence a correlation study carried out between H/sup */and SO/sub 4//sup --/, NO/sub 3/ and Cl. Result shows no strong correlation between H/sup +/ and Cl/up -/. A group of strongly corrected elements Cl, Na/sup +/,K/sup +/ and Mg/sup ++/ were observed representing a similar source of their origin. The atmospheric desert dust components chiefly consist of quartz, mica flakes, clays like illite, kaolinite etc., and especially clays, may neutralize the acidity of precipitates via H/sup +/ exchange. Some minerals like Halite, Gypsum, Dolomite, Calcite may get slightly dissolved in the rainwater to replace H/sup +/ ions and so, impart alkalinity. Thus, it is logical to believe that the cations may have been derived originally from some of the geological source. Some rations like Cl/Na, Mg/Na, Ca/Na are known to have been used in characterization of the source. As expected in the atmosphere of desert city, like Jodhpur, the solid

  3. Characterization and Source Term Assessments of Radioactive Particles from Marshall Islands Using Non-Destructive Analytical Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Jernstrom, J; Eriksson, M; Simon, R; Tamborini, G; Bildstein, O; Carlos-Marquez, R; Kehl, S R; Betti, M; Hamilton, T

    2005-06-11

    A considerable fraction of radioactivity entering the environment from different nuclear events is associated with particles. The impact of these events can only be fully assessed where there is some knowledge about the mobility of particle bound radionuclides entering the environment. The behavior of particulate radionuclides is dependent on several factors, including the physical, chemical and redox state of the environment, the characteristics of the particles (e.g., the chemical composition, crystallinity and particle size) and on the oxidative state of radionuclides contained in the particles. Six plutonium-containing particles stemming from Runit Island soil (Marshall Islands) were characterized using non-destructive analytical and microanalytical methods. By determining the activity of {sup 239,240}Pu and {sup 241}Am isotopes from their gamma peaks structural information related to Pu matrix was obtained, and the source term was revealed. Composition and elemental distribution in the particles were studied with synchrotron radiation based micro X-ray fluorescence (SR-{mu}-XRF) spectrometry. Scanning electron microscope equipped with energy dispersive X-ray detector (SEMEDX) and secondary ion mass spectrometer (SIMS) were used to examine particle surfaces. Based on the elemental composition the particles were divided into two groups; particles with plain Pu matrix, and particles where the plutonium is included in Si/O-rich matrix being more heterogeneously distributed. All of the particles were identified as fragments of initial weapons material. As containing plutonium with low {sup 240}Pu/{sup 239}Pu atomic ratio, {approx}2-6%, which corresponds to weapons grade plutonium, the source term was identified to be among the safety tests conducted in the history of Runit Island.

  4. Development and characterization of a high yield transportable pulsed neutron source with efficient and compact pulsed power system

    Science.gov (United States)

    Verma, Rishi; Mishra, Ekansh; Dhang, Prosenjit; Sagar, Karuna; Meena, Manraj; Shyam, Anurag

    2016-09-01

    The results of characterization experiments carried out on a newly developed dense plasma focus device based intense pulsed neutron source with efficient and compact pulsed power system are reported. Its high current sealed pseudospark switch based low inductance capacitor bank with maximum stored energy of ˜10 kJ is segregated into four modules of ˜2.5 kJ each and it cumulatively delivers peak current in the range of 400 kA-600 kA (corresponding to charging voltage range of 14 kV-18 kV) in a quarter time period of ˜2 μs. The neutron yield performance of this device has been optimized by discretely varying deuterium filling gas pressure in the range of 6 mbar-11 mbar at ˜17 kV/550 kA discharge. At ˜7 kJ/8.5 mbar operation, the average neutron yield has been measured to be in the order of ˜4 × 109 neutrons/pulse which is the highest ever reported neutron yield from a plasma focus device with the same stored energy. The average forward to radial anisotropy in neutron yield is found to be ˜2. The entire system is contained on a moveable trolley having dimensions 1.5 m × 1 m × 0.7 m and its operation and control (up to the distance of 25 m) are facilitated through optically isolated handheld remote console. The overall compactness of this system provides minimum proximity to small as well as large samples for irradiation. The major intended application objective of this high neutron yield dense plasma focus device development is to explore the feasibility of active neutron interrogation experiments by utilization of intense pulsed neutron sources.

  5. Characterization of the in situ magnetic architecture of oceanic crust (Hess Deep) using near-source vector magnetic data

    Science.gov (United States)

    Tominaga, Masako; Tivey, Maurice A.; MacLeod, Christopher J.; Morris, Antony; Lissenberg, C. Johan; Shillington, Donna J.; Ferrini, Vicki

    2016-06-01

    Marine magnetic anomalies are a powerful tool for detecting geomagnetic polarity reversals, lithological boundaries, topographic contrasts, and alteration fronts in the oceanic lithosphere. Our aim here is to detect lithological contacts in fast-spreading lower crust and shallow mantle by characterizing magnetic anomalies and investigating their origins. We conducted a high-resolution, near-bottom, vector magnetic survey of crust exposed in the Hess Deep "tectonic window" using the remotely operated vehicle (ROV) Isis during RRS James Cook cruise JC21 in 2008. Hess Deep is located at the western tip of the propagating rift of the Cocos-Nazca plate boundary near the East Pacific Rise (EPR) (2°15'N, 101°30'W). ROV Isis collected high-resolution bathymetry and near-bottom magnetic data as well as seafloor samples to determine the in situ lithostratigraphy and internal structure of a section of EPR lower crust and mantle exposed on the steep (~20°dipping) south facing slope just north of the Hess Deep nadir. Ten magnetic profiles were collected up the slope using a three-axis fluxgate magnetometer mounted on ROV Isis. We develop and extend the vertical magnetic profile (VMP) approach of Tivey (1996) by incorporating, for the first time, a three-dimensional vector analysis, leading to what we here termed as "vector vertical magnetic profiling" approach. We calculate the source magnetization distribution, the deviation from two dimensionality, and the strike of magnetic boundaries using both the total field Fourier-transform inversion approach and a modified differential vector magnetic analysis. Overall, coherent, long-wavelength total field anomalies are present with a strong magnetization contrast between the upper and lower parts of the slope. The total field anomalies indicate a coherently magnetized source at depth. The upper part of the slope is weakly magnetized and magnetic structure follows the underlying slope morphology, including a "bench" and lobe

  6. Processing and characterization of diatom nanoparticles and microparticles as potential source of silicon for bone tissue engineering.

    Science.gov (United States)

    Le, Thi Duy Hanh; Bonani, Walter; Speranza, Giorgio; Sglavo, Vincenzo; Ceccato, Riccardo; Maniglio, Devid; Motta, Antonella; Migliaresi, Claudio

    2016-02-01

    Silicon plays an important role in bone formation and maintenance, improving osteoblast cell function and inducing mineralization. Often, bone deformation and long bone abnormalities have been associated with silica/silicon deficiency. Diatomite, a natural deposit of diatom skeleton, is a cheap and abundant source of biogenic silica. The aim of the present study is to validate the potential of diatom particles derived from diatom skeletons as silicon-donor materials for bone tissue engineering applications. Raw diatomite (RD) and calcined diatomite (CD) powders were purified by acid treatments, and diatom microparticles (MPs) and nanoparticles (NPs) were produced by fragmentation of purified diatoms under alkaline conditions. The influence of processing on the surface chemical composition of purified diatomites was evaluated by X-ray photoelectron spectroscopy (XPS). Diatoms NPs were also characterized in terms of morphology and size distribution by transmission electron microscopy (TEM) and Dynamic light scattering (DLS), while diatom MPs morphology was analyzed by scanning electron microscopy (SEM). Surface area and microporosity of the diatom particles were evaluated by nitrogen physisorption methods. Release of silicon ions from diatom-derived particles was demonstrated using inductively coupled plasma optical emission spectrometry (ICP/OES); furthermore, silicon release kinetic was found to be influenced by diatomite purification method and particle size. Diatom-derived microparticles (MPs) and nanoparticles (NPs) showed limited or no cytotoxic effect in vitro depending on the administration conditions.

  7. ISOLATION, SCREENING, CHARACTERIZATION AND DETERMINATION OF B-COMPLEX VITAMINS BY LACTOBACILLUS STRAINS FROM DIFFERENT SOURCES OF MEAT

    Directory of Open Access Journals (Sweden)

    Abishek Manisagar

    2012-06-01

    Full Text Available In this study, isolation, screening, characterization, antibiotic susceptibility tests, curing & Determination of B-complex vitamin production by potent probiotic Lactobacillus strains from different sources of meat was analysed. 250 grams of intestine parts of goat meat and beef each were transferred to MRS broth to screen the potent probiotic Lactobacillus strains. Initially 57 strains were isolated and confirmed by gram`s staining and catalase tests. After that, 51 strains selected for further biochemical tests to confirm all were Lactobacillus. Later, 41 strains were selected for antibiotic susceptibility tests by using three different classes of antibiotics viz., tetracycline, ampicilin, and streptomycin. Those strains which showed resistant to all three antibiotics used, further selected for curing of plasmid DNA and again antibiotic susceptibility tests was performed by the same antibiotics used before. Finally, only 5 strains were selected as potent probiotic Lactobacillus and unfortunately all strains from Beef intestine derived. Then, determination of B-Complex vitamin production of those selected 5 potent probiotic Lactobacillus by thin layer chromatographic method; Spectroflurophotometric method and RP-HPLC method were performed. From those methods confirmed as, all the five Lactobacillus strains were producing only riboflavin among the B-Complex vitamins, in trace amounts when compared to standard riboflavin and control (media without Lactobacillus. Those five isolated potent probiotic strains of Lactobacillus were named as B-01; B-06; B-12; B-21 & B-23. (The term B refers Lactobacillus strains isolated from Beef intestine and numeric value refers particular strain.

  8. Characterization of a Low-Cost Optical Flow Sensor When Using an External Laser as a Direct Illumination Source

    Directory of Open Access Journals (Sweden)

    Jordi Palacín

    2011-12-01

    Full Text Available In this paper, a low cost optical flow sensor is combined with an external laser device to measure surface displacements and mechanical oscillations. The measurement system is based on applying coherent light to a diffuser surface and using an optical flow sensor to analyze the reflected and transferred light to estimate the displacement of the surface or the laser spot. This work is focused on the characterization of this measurement system, which can have the optical flow sensor placed at different angles and distances from the diffuser surface. The results have shown that the displacement of the diffuser surface is badly estimated when the optical mouse sensor is placed in front of the diffuser surface (angular orientation >150° while the highest sensitivity is obtained when the sensor is located behind the diffuser surface and on the axis of the laser source (angular orientation 0°. In this case, the coefficient of determination of the measured displacement, R2, was very high (>0.99 with a relative error of less than 1.29%. Increasing the distance between the surface and the sensor also increased the sensitivity which increases linearly, R2 = 0.99. Finally, this measurement setup was proposed to measure very low frequency mechanical oscillations applied to the laser device, up to 0.01 Hz in this work. The results have shown that increasing the distance between the surface and the optical flow sensor also increases the sensitivity and the measurement range.

  9. A Sr-Nd-Hf isotope characterization of dust source areas in Victoria Land and the McMurdo Sound sector of Antarctica

    Science.gov (United States)

    Blakowski, Molly A.; Aciego, Sarah M.; Delmonte, Barbara; Baroni, Carlo; Salvatore, Maria Cristina; Sims, Kenneth W. W.

    2016-06-01

    Determining the geographical provenance of dust provides crucial insight into the global dust cycle. For the East Antarctic Ice Sheet (EAIS), the importance of Southern hemisphere potential dust sources has been thoroughly investigated using radiogenic isotopes, whereas proximal dust source areas located on the periphery of the ice sheet remain poorly documented from a geochemical standpoint. In this work, we expand the existing isotopic (Srsbnd Nd) catalogue of dust and sand-sized sediments from Victoria Land and the McMurdo Sound sector, and incorporate Hf isotopic data to place additional constraints on dust source identification. The isotopic field for materials considered in this study is characterized by 87Sr/86Sr ratios ranging from 0.703 to 0.783, εNd between -12.01 and 6.36, and εHf from -16.77 to 6.89. As reported in previous works, the data reveal close relationships between Antarctic sediments and distinct parent lithologies; in addition, our findings emphasize the background presence of very fine dusts originating from dominant global sources and regional volcanic activity as barriers to direct source-to-sink comparison of isotopic signatures. Thus, geochemical characterizations of dust sources to the Antarctic ice sheet involving multiple size fractions, including coarser-grained particles more susceptible to short-range transport, can help us to rule out global sources of dust when examining local sediment cores and ice cores.

  10. Geochemical characterization of fluids along the Dead Sea Rift: implications for fluids sources and regional geodynamic setting

    Science.gov (United States)

    Inguaggiato, Claudio; Censi, Paolo; D'Alessandro, Walter; Zuddas, Pierpaolo

    2016-04-01

    The Dead Sea Fault where a lateral displacement between the African and Arabian plates occurs is characterized by anomalous heat flux in the northern Israel area close to the border with Syria and Jordan (Shalev et al., 2012). The concentrations of He and CO2, and isotopic composition of He and total dissolved inorganic carbon were studied in cold and thermal waters collected along the Dead Sea Fault, in order to investigate the source of volatiles and their relationship with the tectonic framework of the Dead Sea Fault. The waters with higher temperature (up to 57.2 ° C) are characterized by higher amounts of CO2and helium (up to 55.72 and 1.91*10‑2 cc l‑1, respectively). Helium isotopic data (R/Ra from 0.11 to 2.14) and 4He/20Ne ratios (0.41 - 106.86) show the presence of deep-deriving fluids consisting of a variable mixture of mantle and crust end-members, with the former reaching up to 35%. Carbon isotope signature of total dissolved carbon from hot waters falls within the range of magmatic values, suggesting the delivery of deep-seated CO2. The geographical distribution of helium isotopic data and isotopic carbon (CO2) values coupled with (CO2/3He ratios) indicate a larger contribution of mantle-derived fluids affecting the northern part of the investigated area, where the waters reach the highest temperature and anomalous heat flux was recognized by Shalev et al. (2012). Such occurrence is probably favoured by the peculiar tectonic framework recognized in the northern part of Israel (Segev et al., 2006), including a Moho discontinuity up-rise and/or the presence of a deep fault system coupled with the recent magmatic activity. References: Segev, A., Rybakov, M., Lyakhovsky, V, Hofstetter, A, Tibor, G., Goldshmidt, V., 2006. The structure, isostasy and gravity field of the Levant continental margin and the southeast Mediterranean area. Tectonophysics 425, 137-157. Shalev, E., Lyakhosky, V., Weinstein, Y., Ben-Avraham, Z., 2013. The thermal structure of

  11. Characterization of two diesel fuel degrading microbial consortia enriched from a non acclimated, complex source of microorganisms

    Directory of Open Access Journals (Sweden)

    Varese Giovanna C

    2010-02-01

    Full Text Available Abstract Background The bioremediation of soils impacted by diesel fuels is very often limited by the lack of indigenous microflora with the required broad substrate specificity. In such cases, the soil inoculation with cultures with the desired catabolic capabilities (bioaugmentation is an essential option. The use of consortia of microorganisms obtained from rich sources of microbes (e.g., sludges, composts, manure via enrichment (i.e., serial growth transfers on the polluting hydrocarbons would provide bioremediation enhancements more robust and reproducible than those achieved with specialized pure cultures or tailored combinations (co-cultures of them, together with none or minor risks of soil loading with unrelated or pathogenic allocthonous microorganisms. Results In this work, two microbial consortia, i.e., ENZ-G1 and ENZ-G2, were enriched from ENZYVEBA (a complex commercial source of microorganisms on Diesel (G1 and HiQ Diesel (G2, respectively, and characterized in terms of microbial composition and hydrocarbon biodegradation capability and specificity. ENZ-G1 and ENZ-G2 exhibited a comparable and remarkable biodegradation capability and specificity towards n-C10 to n-C24 linear paraffins by removing about 90% of 1 g l-1 of diesel fuel applied after 10 days of aerobic shaken flask batch culture incubation at 30°C. Cultivation dependent and independent approaches evidenced that both consortia consist of bacteria belonging to the genera Chryseobacterium, Acinetobacter, Psudomonas, Stenotrophomonas, Alcaligenes and Gordonia along with the fungus Trametes gibbosa. However, only the fungus was found to grow and remarkably biodegrade G1 and G2 hydrocarbons under the same conditions. The biodegradation activity and specificity and the microbial composition of ENZ-G1 and ENZ-G2 did not significantly change after cryopreservation and storage at -20°C for several months. Conclusions ENZ-G1 and ENZ-G2 are very similar highly enriched consortia

  12. Full characterization of self-phase-modulation based low-noise, cavity-less pulse source for photonic-assisted analog-to-digital conversion.

    Science.gov (United States)

    Liu, Lan; Tong, Zhi; Wiberg, Andreas O J; Myslivets, Evgeny; Alic, Nikola; Radic, Stojan

    2012-12-10

    A high quality cavity-less pulse source, realized as a combination of linear pulse compression and self-phase-modulation (SPM) based regeneration is demonstrated and strictly characterized for the first time. The regenerated pulses, with 3.6 GHz repetition rate, are optimized through rigorous relative intensity-noise (RIN) measurement. Temporal intensity and chirp characterizations demonstrate that the pulses exhibit characteristic of low RIN, and are chirp- and pedestal-free. The cavity-less pulse source is further tested in a photonic-assisted analog-to-digital (ADC) configuration as the sampling source. A record result of more than 8 effective quantization bits at 202 MHz is demonstrated. PMID:23262840

  13. Characterization and sources assignation of PM2.5 organic aerosol in a rural area of Spain

    Science.gov (United States)

    Pindado, Oscar; Pérez, Rosa M. a.; García, Susana; Sánchez, Miguel; Galán, Pilar; Fernández, Marta

    The results from a year-long study of the organic composition of PM2.5 aerosol collected in a rural area influenced by a highway of Spain are reported. The lack of prior information related to the organic composition of PM2.5 aerosol in Spain, concretely in rural areas, led definition of the goals of this study. As a result, this work has been able to characterize the main organic components of atmospheric aerosols, including several compounds of SOA, and has conducted a multivariate analysis in order to assign sources of particulate matter. A total of 89 samples were taken between April 2004 and April 2005 using a high-volume sampler. Features and abundance of n-alkanes, polycyclic aromatic hydrocarbons (PAHs), alcohols and acids were separately determined using gas chromatography/mass spectrometry and high performance liquid chromatography analysis. The Σ n-alkane and ΣPAHs ranged from 3 to 81 ng m -3 and 0.1 to 6 ng m -3 respectively, with higher concentrations during colder months. Ambient concentrations of Σalcohols and Σacids ranged from 21 to 184 ng m -3 and 39 to 733 ng m -3, respectively. Also, several components of secondary organic aerosol have been quantified, confirming the biogenic contribution to ambient aerosol. In addition, factor analysis was used to reveal origin of organic compounds associated to particulate matter. Eight factors were extracted accounting more than 83% of the variability in the original data. These factors were assigned to a typical high pollution episode by anthropogenic particles, crustal material, plant waxes, fossil fuel combustion, temperature, microbiological emissions, SOA and dispersion of pollutants by wind action. Finally, a cluster analysis was used to compare the organic composition between the four seasons.

  14. Characterization and source apportionment of submicron aerosol with aerosol mass spectrometer during the PRIDE-PRD 2006 campaign

    Science.gov (United States)

    Xiao, R.; Takegawa, N.; Zheng, M.; Kondo, Y.; Miyazaki, Y.; Miyakawa, T.; Hu, M.; Shao, M.; Zeng, L.; Gong, Y.; Lu, K.; Deng, Z.; Zhao, Y.; Zhang, Y. H.

    2011-07-01

    Size-resolved chemical compositions of non-refractory submicron aerosol were measured using an Aerodyne quadrupole aerosol mass spectrometer (Q-AMS) at the rural site Back Garden (BG), located ~50 km northwest of Guangzhou in July 2006. This paper characterized the submicron aerosol particles of regional air pollution in Pearl River Delta (PRD) in the southern China. Organics and sulfate dominated the submicron aerosol compositions, with average mass concentrations of 11.8 ± 8.4 μg m-3 and 13.5 ± 8.7 μg m-3, respectively. Unlike other air masses, the air masses originated from Southeast-South and passing through the PRD urban areas exhibited distinct bimodal size distribution characteristics for both organics and sulfate: the first mode peaked at vacuum aerodynamic diameters (Dva) ∼200 nm and the second mode occurred at Dva from 300-700 nm. With the information from AMS, it was found from this study that the first mode of organics in PRD regional air masses was contributed by both secondary organic aerosol formation and combustion-related emissions, which is different from most findings in other urban areas (first mode of organics primarily from combustion-related emissions). The analysis of AMS mass spectra data by positive matrix factorization (PMF) model identified three sources of submicron organic aerosol including hydrocarbon-like organic aerosol (HOA), low volatility oxygenated organic aerosol (LV-OOA) and semi-volatile oxygenated organic aerosol (SV-OOA). The strong correlation between HOA and EC indicated primary combustion emissions as the major source of HOA while a close correlation between SV-OOA and semi-volatile secondary species nitrate as well as between LV-OOA and nonvolatile secondary species sulfate suggested secondary aerosol formation as the major source of SV-OOA and LV-OOA at the BG site. However, LV-OOA was more aged than SV-OOA as its spectra was highly correlated with the reference spectra of fulvic acid, an indicator of aged and

  15. Applications of open-path Fourier transform infrared for identification of volatile organic compound pollution sources and characterization of source emission behaviors.

    Science.gov (United States)

    Lin, Chitsan; Liou, Naiwei; Sun, Endy

    2008-06-01

    An open-path Fourier transform infrared spectroscopy (OP-FTIR) system was set up for 3-day continuous line-averaged volatile organic compound (VOC) monitoring in a paint manufacturing plant. Seven VOCs (toluene, m-xylene, p-xylene, styrene, methanol, acetone, and 2-butanone) were identified in the ambient environment. Daytime-only batch operation mode was well explained by the time-series concentration plots. Major sources of methanol, m-xylene, acetone, and 2-butanone were identified in the southeast direction where paint solvent manufacturing processes are located. However, an attempt to uncover sources of styrene was not successful because the method detection limit (MDL) of the OP-FTIR system was not sensitive enough to produce conclusive data. In the second scenario, the OP-FTIR system was set up in an industrial complex to distinguish the origins of several VOCs. Eight major VOCs were identified in the ambient environment. The pollutant detected wind-rose percentage plots that clearly showed that ethylene, propylene, 2-butanone, and toluene mainly originated from the tank storage area, whereas the source of n-butane was mainly from the butadiene manufacturing processes of the refinery plant, and ammonia was identified as an accompanying reduction product in the gasoline desulfuration process. Advantages of OP-FTIR include its ability to simultaneously and continuously analyze many compounds, and its long path length monitoring has also shown advantages in obtaining more comprehensive data than the traditional multiple, single-point monitoring methods.

  16. Characterization of the deep-sea microbial community and investigation of their carbon sources using lipid biomarkers

    Science.gov (United States)

    Rampen, S. W.; Sinninghe Damsté, J. S.; Schouten, S.; Middelburg, J. J.

    2012-12-01

    Most marine microbiology studies so far have been devoted to the photic zone, as this is the area where most of the primary production occurs. However, recently several groups of autotrophic organisms belonging to the Thaumarchaeota have been identified in the deep-sea. Thaumarchaeota belong to the Archaea, which form one of the three Domains of life, next to the Eukarya and the Bacteria. While until the 1990s the Archaea were viewed as extremophilic organisms, results obtained over the last twenty years indicate that Thaumarchaeota are an ubiquitous component of marine plankton, being among the most widely distributed and most abundant groups of microorganisms on the planet; Thaumarchaeota even exceed Bacteria in abundance below 1000 m water depth. Despite these findings, our understanding on their physiology and their biogeochemical function remains mostly speculative because only very few of these organisms could be cultivated. The aim of our project is 1) to characterize the microbial community in the deep-sea using lipid biomarkers for Bacteria, Archaea and Eukarya, 2) to investigate the carbon sources for these organisms using compound specific 13C and 14C analyses and 3) to elucidate the flow of carbon in deep-sea microbial communities using 13C labeling studies. To this end, organic matter has been collected from several locations in the Mediterranean Sea and from the Iceland Basin. Water volumes up to 160 liters were sampled using Niskin bottles which were then filtered on board, while larger volumes, up to 5000 liters, were sampled by deployment of two McLane in-situ pumps at depth. Additional water samples were filtered from the subsurface to distinguish in-situ production from settling organic biomass produced in the upper water column. In addition, 13C labeled glucose, amino acids and sodium bicarbonate were each added to deep-sea water kept in separate 20 liter Nalgene bottles. Incubated water samples and control samples were kept at deep

  17. Characterization of concentration, particle size distribution, and contributing factors to ambient hexavalent chromium in an area with multiple emission sources

    Science.gov (United States)

    Yu, Chang Ho; Huang, Lihui; Shin, Jin Young; Artigas, Francisco; Fan, Zhi-hua (Tina)

    2014-09-01

    Airborne hexavalent chromium (Cr(VI)) is a known pulmonary carcinogen and can be emitted from both natural and anthropogenic sources, including diesel emissions. However, there is limited knowledge about ambient Cr(VI) concentration levels and its particle size distribution. This pilot study characterized ambient Cr(VI) concentrations in the New Jersey Meadowlands (NJ ML) district, which is close to the heavily trafficked New Jersey Turnpike (NJTPK) as well as Chromium Ore Processing Residue (COPR) waste sites. Monitoring was simultaneously conducted at two sites, William site (∼50 m from NJTPK) and MERI site (∼700 m from NJTPK). The distance between the two sites is approximately 6.2 km. Ambient Cr(VI) concentrations and PM2.5 mass concentrations were concurrently measured at both sites during summer and winter. The summer concentrations (mean ± S.D. [median]), 0.13 ± 0.06 [0.12] ng/m3 at the MERI site and 0.08 ± 0.05 [0.07] ng/m3 at the William site, were all significantly higher than the winter concentrations, 0.02 ± 0.01 [0.02] ng/m3 and 0.03 ± 0.01 [0.03] ng/m3 at the MERI and William sites, respectively. The site difference (i.e., MERI > William) was observed for summer Cr(VI) concentrations; however, no differences for winter and pooled datasets. These results suggest higher Cr(VI) concentrations may be attributed from stronger atmospheric reactions such as photo-oxidation of Cr(III) to Cr(VI) in the summer. The Cr(VI) distribution as a function of particle size, ranging from 0.18 to 18 μm, was determined at the William site. It was found that Cr(VI) was enriched in the particles less than 2.5 μm in diameter (PM2.5). This finding suggested potential health concerns, because PM2.5 are easily inhaled and deposited in the alveoli. A multiple linear regression analysis confirmed ambient Cr(VI) concentrations were significantly affected by meteorological factors (i.e., temperature and humidity) and reactive gases/particles (i.e., O3, Fe and Mn).

  18. Extended Characterization of the Common-Source and Common-Gate Amplifiers using a Metal-Ferroelectric-Semiconductor Field Effect Transistor

    Science.gov (United States)

    Hunt, Mitchell; Sayyah, Rana; Mitchell, Cody; Laws, Crystal; MacLeod, Todd C.; Ho, Fat D.

    2013-01-01

    Collected data for both common-source and common-gate amplifiers is presented in this paper. Characterizations of the two amplifier circuits using metal-ferroelectric-semiconductor field effect transistors (MFSFETs) are developed with wider input frequency ranges and varying device sizes compared to earlier characterizations. The effects of the ferroelectric layer's capacitance and variation load, quiescent point, or input signal on each circuit are discussed. Comparisons between the MFSFET and MOSFET circuit operation and performance are discussed at length as well as applications and advantages for the MFSFETs.

  19. Characterization and source identification of pollutants in runoff from a mixed land use watershed using ordination analyses.

    Science.gov (United States)

    Lee, Dong Hoon; Kim, Jin Hwi; Mendoza, Joseph A; Lee, Chang Hee; Kang, Joo-Hyon

    2016-05-01

    While identification of critical pollutant sources is the key initial step for cost-effective runoff management, it is challenging due to the highly uncertain nature of runoff pollution, especially during a storm event. To identify critical sources and their quantitative contributions to runoff pollution (especially focusing on phosphorous), two ordination methods were used in this study: principal component analysis (PCA) and positive matrix factorization (PMF). For the ordination analyses, we used runoff quality data for 14 storm events, including data for phosphorus, 11 heavy metal species, and eight ionic species measured at the outlets of subcatchments with different land use compositions in a mixed land use watershed. Five factors as sources of runoff pollutants were identified by PCA: agrochemicals, groundwater, native soils, domestic sewage, and urban sources (building materials and automotive activities). PMF identified similar factors to those identified by PCA, with more detailed source mechanisms for groundwater (i.e., nitrate leaching and cation exchange) and urban sources (vehicle components/motor oils/building materials and vehicle exhausts), confirming the sources identified by PCA. PMF was further used to quantify contributions of the identified sources to the water quality. Based on the results, agrochemicals and automotive activities were the two dominant and ubiquitous phosphorus sources (39-61 and 16-47 %, respectively) in the study area, regardless of land use types. PMID:26850099

  20. Treatability Test Report: Characterization of Vadose Zone Carbon Tetrachloride Source Strength Using Tomographic Methods at the 216-Z-9 Site

    Energy Technology Data Exchange (ETDEWEB)

    Truex, Michael J.; Carroll, Kenneth C.; Rohay, Virginia J.; Mackley, Rob D.; Parker, Kyle R.

    2012-09-28

    A treatability test was conducted in 2011 at the 216-Z-9 Trench to evaluate methods for collecting characterization information that supports refined assessment of SVE performance goals based on impact to groundwater. The characterization information can also provide input to operational strategies for continued SVE operation and decisions regarding closure of the SVE system or transition to other remedies, if necessary.

  1. Neutron characterization study for D–T, p-{sup 7}Li neutron sources with new BCA based direct collision coupling method

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Guan-bo, E-mail: wgb04dep@hotmail.com [Insititute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900 (China); Yang, Xin [Insititute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900 (China); Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Qian, Da-zhi; Li, Run-dong; Tang, Bin [Insititute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900 (China)

    2014-09-01

    The T(D,n){sup 4}He and {sup 7}Li(p,n){sup 7}Be neutron sources have been used for decades in nuclear physics research, stellar nucleosynthesis research and neutron therapy research. In this work, the neutron characterization including neutron yield, spectra, and angular distribution for D–T and p-{sup 7}Li sources have been studied with our new binary collision approximation (BCA) based direct collision coupling method. Distinguished from the traditional path integration method for getting the neutron weight, the new model establishes a relationship between the scattering cross section and the impact parameter, which allows the secondary neutron generation carrying out jointly with ions BCA tracking. The experimental measurements of neutron characterizations have been employed for these two reactions, and the new algorithm is validated.

  2. MEG (Magnetoencephalography) multipolar modeling of distributed sources using RAP-MUSIC (Recursively Applied and Projected Multiple Signal Characterization)

    Energy Technology Data Exchange (ETDEWEB)

    Mosher, J. C. (John C.); Baillet, S. (Sylvain); Jerbi, K. (Karim); Leahy, R. M. (Richard M.)

    2001-01-01

    We describe the use of truncated multipolar expansions for producing dynamic images of cortical neural activation from measurements of the magnetoencephalogram. We use a signal-subspace method to find the locations of a set of multipolar sources, each of which represents a region of activity in the cerebral cortex. Our method builds up an estimate of the sources in a recursive manner, i.e. we first search for point current dipoles, then magnetic dipoles, and finally first order multipoles. The dynamic behavior of these sources is then computed using a linear fit to the spatiotemporal data. The final step in the procedure is to map each of the multipolar sources into an equivalent distributed source on the cortical surface. The method is illustrated through an application to epileptic interictal MEG data.

  3. Seismic source characterization of the Alpine foreland in the context of a probabilistic seismic hazard analysis by PEGSOS Expert Group 1 (EG1a)

    OpenAIRE

    Schmid, Stefan M.; Slejko, Dario

    2009-01-01

    Seismic source characterization is performed as part of the PEGASOS project for the assessment of the seismic hazard at the 4 sites of the Swiss Nuclear Power Plants. The analysis is performed according to the Level 4 procedures for expert elicitation defined in the guidelines of the US Nuclear Regulatory Committee whereby the quantification of uncertainties plays a crucial role. According to our analysis, which is one amongst four that were performed in the frame of PEGASOS, the most importa...

  4. Synthesis and characterization of CdS and CdSe nanoparticles prepared from novel intramolecularly stabilized single-source precursors

    Indian Academy of Sciences (India)

    Karuppasamy Kandasamy; Harkesh B Singh; Shailendra K Kulshreshtha

    2009-05-01

    In this note we describe the synthesis of cadmium sulphide and selenide nanoparticles from the corresponding novel single source precursors, M[E(Ox)]2 [E = S (1), Se (2); M = Cd; Ox = 2-(4,4-dimethyl-2-oxazolinyl)benzene] by thermolysing in tri--octylphosphine oxide (TOPO) at 280°C, and their characterization by X-ray powder diffraction (XRD), transmission electron microscope (TEM) and scanning electron microscope (SEM) studies.

  5. Characterization and quantification of groundwater sulfate sources at a mining site in an arid climate: The Monument Valley site in Arizona, USA

    Science.gov (United States)

    Miao, Ziheng; Carroll, Kenneth C.; Brusseau, Mark L.

    2014-01-01

    The Monument Valley site, a former uranium mining site located in the state of Arizona in the Southwest USA, has high concentrations of sulfate in groundwater. Stable isotope analysis of S and O for sulfate, in combination with geochemical and hydrogeological data, was used to characterize the sources and fate of sulfate. The results indicate the existence of two discrete sources of sulfate (in excess of baseline levels): sulfuric acid released during ore processing and sulfate generated via sulfide-mineral oxidation. The contributions of the sources are related to spatial distributions of sulfate in the plume through analysis of groundwater travel times. Quantification of the sources using two isotope-analysis methods yielded similar results. The results indicate that sulfuric acid served as the primary source (mean = 427 mg/L, 74%), with sulfide-mineral oxidation providing a smaller contribution (mean = 147 mg/L, 26%). It appears that the major contribution to the sulfide-mineral oxidation component originates from oxidation of sulfide minerals in exposed bedrock residing in the primary recharge zone of the local aquifer, which provides an elevated sulfate background for groundwater. Conversely, the oxidation of sulfide minerals associated with the mine tailings appears to provide a relatively minor contribution (∼8% of the overall total). Interestingly, it appears that sulfuric acid served as a sustained source of sulfate for approximately 40 years. This may be related to the accumulation of sulfate salts (formed after neutralization and disposal of the sulfuric acid) in the source zone due to the arid climate of the site. Contrary to the typical assumption applied at many mining sites that sulfide-mineral oxidation is the primary source of sulfate, these sulfate salts are hypothesized to be the primary source for this site. PMID:24729633

  6. Monte Carlo dosimetric characterization of the Cs-137 selectron/LDR source: Evaluation of applicator attenuation and superposition approximation effects

    International Nuclear Information System (INIS)

    The purpose of this study is to calculate the dose rate distribution for the Amersham Cs-137 pellet source used in brachytherapy with the Selectron low-dose-rate remote afterloading system in gynaecological applications using the Monte Carlo code GEANT4. The absolute dose rate distribution for the pellet source was obtained and presented as a one-dimensional absolute dose rate table as well as in the Task Group 43 dose-calculation formalism. In this study, excellent agreement was found between the point source theoretical model using fitted polynomial values and Monte Carlo calculations of the dose rate distribution for the pellet source. A comparison study was also made between the dose rate distribution obtained from a complete Monte Carlo simulation (Cs-137 pellet sources+remote afterloading system plastic guide tube+gynaecological applicator) and that calculated by applying the superposition principle to Monte Carlo data of the individual pellet sources. The data were obtained for a portion of uterine tandem of typical train source configurations. Significant differences with a strong dependence on polar angle have been found that must be kept in mind for clinical dosimetry

  7. Characterization and source apportionment of health risks from ambient PM10 in Hong Kong over 2000-2011

    Science.gov (United States)

    Li, Zhiyuan; Yuan, Zibing; Li, Ying; Lau, Alexis K. H.; Louie, Peter K. K.

    2015-12-01

    Atmospheric particulate matter (PM) pollution is a major public health concern in Hong Kong. In this study, the spatiotemporal variations of health risks from ambient PM10 from seven air quality monitoring stations between 2000 and 2011 were analyzed. Positive matrix factorization (PMF) was adopted to identify major source categories of ambient PM10 and quantify their contributions. Afterwards, a point-estimated risk model was used to identify the inhalation cancer and non-cancer risks of PM10 sources. The long-term trends of the health risks from classified local and non-local sources were explored. Furthermore, the reason for the increase of health risks during high PM10 days was discussed. Results show that vehicle exhaust source was the dominant inhalation cancer risk (ICR) contributor (72%), whereas trace metals and vehicle exhaust sources contributed approximately 27% and 21% of PM10 inhalation non-cancer risk (INCR), respectively. The identified local sources accounted for approximately 80% of the ICR in Hong Kong, while contribution percentages of the non-local and local sources for INCR are comparable. The clear increase of ICR at high PM days was mainly attributed to the increase of contributions from coal combustion/biomass burning and secondary sulfate, while the increase of INCR at high PM days was attributed to the increase of contributions from the sources coal combustion/biomass burning, secondary nitrate, and trace metals. This study highlights the importance of health risk-based source apportionment in air quality management with protecting human health as the ultimate target.

  8. Molecular characterization of chordoma xenografts generated from a novel primary chordoma cell source and two chordoma cell lines

    Science.gov (United States)

    Karikari, Isaac O.; Gilchrist, Christopher L.; Jing, Liufang; Alcorta, David A.; Chen, Jun; Richardson, William J.; Gabr, Mostafa A.; Bell, Richard D.; Kelley, Michael J.; Bagley, Carlos A.; Setton, Lori A.

    2014-01-01

    Object Chordoma cells can generate solid-like tumors in xenograft models that express some molecular characteristics of the parent tumor, including positivity for brachyury and cytokeratins. However, there is a dearth of molecular markers that relate to chordoma tumor growth, as well as the cell lines needed to advance treatment. The objective in this study was to isolate a novel primary chordoma cell source and analyze the characteristics of tumor growth in a mouse xenograft model for comparison with the established U-CH1 and U-CH2b cell lines. Methods Primary cells from a sacral chordoma, called “DVC-4,” were cultured alongside U-CH1 and U-CH2b cells for more than 20 passages and characterized for expression of CD24 and brachyury. While brachyury is believed essential for driving tumor formation, CD24 is associated with healthy nucleus pulposus cells. Each cell type was subcutaneously implanted in NOD/SCID/IL2Rγnull mice. The percentage of solid tumors formed, time to maximum tumor size, and immunostaining scores for CD24 and brachyury (intensity scores of 0–3, heterogeneity scores of 0–1) were reported and evaluated to test differences across groups. Results The DVC-4 cells retained chordoma-like morphology in culture and exhibited CD24 and brachyury expression profiles in vitro that were similar to those for U-CH1 and U-CH2b. Both U-CH1 and DVC-4 cells grew tumors at rates that were faster than those for U-CH2b cells. Gross tumor developed at nearly every site (95%) injected with U-CH1 and at most sites (75%) injected with DVC-4. In contrast, U-CH2b cells produced grossly visible tumors in less than 50% of injected sites. Brachyury staining was similar among tumors derived from all 3 cell types and was intensely positive (scores of 2–3) in a majority of tissue sections. In contrast, differences in the pattern and intensity of staining for CD24 were noted among the 3 types of cell-derived tumors (p < 0.05, chi-square test), with evidence of intense

  9. Characterization of Wet and Dry Deposition in the Downwind of Industrial Sources in a Dry Tropical Area

    Directory of Open Access Journals (Sweden)

    Raj K. Singh

    2001-01-01

    Full Text Available An atmospheric deposition study was conducted in the downwind of Shaktinagar Thermal Power Plant (STPP, Renusagar Thermal Power Plant (RTPP, and Anpara Thermal Power Plant (ATPP, at Singrauli region, Uttar Pradesh (UP, India to characterize dry and wet deposition in relation to different pollution loading. During the study period, dry and wet depositions and levels of gaseous pollutants (SO2 and NO2 were estimated across the sites. Dry deposition was collected on a monthly basis and wet deposition on an event basis. Depositions were analyzed for pH, nitrate (NO3�, ammonium (NH4+, and sulphate (SO42� contents. Dry deposition rate both collected as clearfall and throughfall varied between 0.15 to 2.28 and 0.33 to 3.48 g m�2 day�1, respectively, at control and maximally polluted sites. The pH of dry deposition varied from 5.81 to 6.89 during winter and 6.09 to 7.02 during summer across the sites. During the rainy season, the mean pH of clear wet deposition varied from 6.56 to 7.04 and throughfall varied from 6.81 to 7.22. The concentrations of NO2 and SO2 pollutants were highest during the winter season. Mean SO2 concentrations varied from 18 to 75 �g m�3 at control and differently polluted sites during the winter season. The variation in NO2 concentrations did not show a pattern similar to that of SO2. The highest NO2 concentration during the winter season was 50 �g m�3, observed near RTPP. NO2 concentration did not show much variation among different sites, suggesting that the sources of NO2 emission are evenly distributed along the sites. The concentrations of NH4+, NO3�, and SO42� ions in dry deposition were found to be higher in summer as compared to the winter season. In dry deposition (clearfall the concentrations of NH4+, NO3�, and SO42� varied from 0.13 to 1.0, 0.81 to 1.95, and 0.82 to 3.27 mg l�1, respectively, during winter. In wet deposition (clearfall, the above varied from 0.14 to 0.74, 0.81 to 1.82, and 0

  10. Comparison of PCR and quantitative real-time PCR methods for the characterization of ruminant and cattle fecal pollution sources

    Science.gov (United States)

    The state of California has mandated the preparation of a guidance document on the application of fecal source identification methods for recreational water quality management. California contains the fifth highest population of cattle in the United States, making the inclusio...

  11. Novelty P3 reductions in depression: characterization using principal components analysis (PCA) of current source density (CSD) waveforms.

    Science.gov (United States)

    Tenke, Craig E; Kayser, Jürgen; Stewart, Jonathan W; Bruder, Gerard E

    2010-01-01

    We previously reported a novelty P3 reduction in depressed patients compared to healthy controls (n=20 per group) in a novelty oddball task using a 31-channel montage. In an independent replication and extension using a 67-channel montage (n=49 per group), reference-free current source density (CSD) waveforms were simplified and quantified by a temporal, covariance-based principal components analysis (PCA) (unrestricted Varimax rotation), yielding factor solutions consistent with other oddball tasks. A factor with a loadings peak at 343 ms summarized the target P3b source as well as a secondary midline frontocentral source for novels and targets. An earlier novelty vertex source (NVS) at 241 ms was present for novels, but not targets, and was reduced in patients. Compatible CSD-PCA findings were also confirmed for the original low-density sample. Results are consistent with a reduced novelty response in clinical depression, involving the early phase of the frontocentral novelty P3.

  12. Characterization of Co-60 sources to the treatment of the ophthalmic tumors using the MCNP-4C code

    International Nuclear Information System (INIS)

    Ophthalmic sources used in the treatment of ophthalmic tumors needed to be periodically controlled in order to have assurance of the administrated dose in the treatment. For this purpose, an human eye was simulated with all structures and composition was simulated by MCNP-4C with an ophthalmic source of Co-60 (model CKA-4 of Amersham). With this simulator, it was possible to determine the dose in the center-eye dephness and also the doses in the structures as retina, coroide, lenses, etc. To check the doses from MCNP-4C, it was realized measurements with radiological films type X-OMAT V of Kodak, with a Co-60 CKA-4 source and an acrylic simulator. The measurement allow the construction of the optical density versus the source distance. This curve will serve as a test data for the calculated dose values of MCNP-4C. (author)

  13. Source Characterization of Volatile Organic Compounds Affecting the Air Quality in a Coastal Urban Area of South Texas

    OpenAIRE

    Kuruvilla John; Saritha Karnae; Marciano Sanchez

    2008-01-01

    Selected Volatile Organic Compounds (VOC) emitted from various anthropogenic sources including industries and motor vehicles act as primary precursors of ozone, while some VOC are classified as air toxic compounds. Significantly large VOC emission sources impact the air quality in Corpus Christi, Texas. This urban area is located in a semi-arid region of South Texas and is home to several large petrochemical refineries and industrial facilities along a busy ship-channel. The Texas Commission ...

  14. Source characterization of nitrous oxide using a stable isotope fingerprint technique; Antei doitai finger print wo riyoshita asanka chisso no hasseigen characterization

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, S. [National Institute for Resources and Environment, Tsukuba (Japan)

    1995-07-25

    The tropospheric mixing ratio of nitrous oxide is increasing 0.25-0.31% annually. A number of studies have been carried out to describe global cycle of nitrous oxide. However, no clear cut understanding has been obtained. For example, stratospheric decomposition of nitrous oxide is significantly larger than the total emission from the earth`s surface to atmosphere. The imbalance suggests existence of unidentified sources. Recently, the tropospheric formation of nitrous oxide has been reported as a forgotten mechanism to provide nitrous oxide to atmosphere. However, its source strength has not been evaluated precisely. Possible error in extrapolating flux determinations at source sites to some large scale may be an additional reason for the imbalance. As nitrous oxide produced by different mechanisms differ in stable isotopic signature, measurement of stable isotope ratio is a way to re-evaluate the global budget. This report discusses the progress that has been made regarding stable isotope study on biogeochemistry of nitrous oxide. 22 refs., 1 fig., 1 tab.

  15. Insights into the chemical characterization and sources of PM(2.5) in Beijing at a 1-h time resolution.

    Science.gov (United States)

    Gao, Jian; Peng, Xing; Chen, Gang; Xu, Jiao; Shi, Guo-Liang; Zhang, Yue-Chong; Feng, Yin-Chang

    2016-01-15

    As the widespread application of online instruments penetrates the environmental fields, it is interesting to investigate the sources of fine particulate matter (PM2.5) based on the data monitored by online instruments. In this study, online analyzers with 1-h time resolution were employed to observe PM2.5 composition data, including carbon components, inorganic ions, heavy metals and gas pollutants, during a summer in Beijing. Chemical characteristics, temporal patterns and sources of PM2.5 are discussed. On the basis of hourly data, the mean concentration value of PM2.5 was 62.16±39.37 μg m(-3) (ranging from 6.69 to 183.67 μg m(-3)). The average concentrations of NO3(-), SO4(2-), NH4(+), OC and EC, the major chemical species, were 15.18±13.12, 14.80±14.53, 8.90±9.51, 9.32±4.16 and 3.08±1.43 μg m(-3), respectively. The concentration of PM2.5 varied during the online-sampling period, initially increasing and then subsequently decreasing. Three factor analysis models, including principal component analysis (PCA), positive matrix factorization (PMF) and Multilinear Engine 2 (ME2), were applied to apportion the PM2.5 sources. Source apportionment results obtained by the three different models were in agreement. Four sources were identified in Beijing during the sampling campaign, including secondary sources (38-39%), crustal dust (17-22%), vehicle exhaust (25-28%) and coal combustion (15-16%). Similar source profiles and contributions of PM2.5 were derived from ME2 and PMF, indicating the results of the two models are reasonable. The finding provides information that could be exploited for regular air control strategies. PMID:26519577

  16. Advances in Methane Isotope Measurements via Direct Absorption Spectroscopy with Applications to Oil and Gas Source Characterization

    Science.gov (United States)

    Yacovitch, T. I.; Herndon, S. C.; Roscioli, J. R.; Petron, G.; Shorter, J. H.; Jervis, D.; McManus, J. B.; Nelson, D. D.; Zahniser, M. S.; Kolb, C. E., Jr.

    2015-12-01

    Instrumental developments in the measurement of multiple isotopes of methane (12CH4, 13CH4 and 12CH3D) are presented. A first generation 8-micron instrument quantifies 12CH4 and 13CH4 at a 1-second rate via tunable infrared direct absorption spectroscopy (TILDAS). A second generation instrument uses two 3-micron intraband cascade lasers in an Aerodyne dual laser chassis for simultaneous measurement of 12CH4, 13CH4 and 12CH3D. Sensitivity and noise performance improvements are examined. The isotopic signature of methane provides valuable information for emission source identification of this greenhouse gas. A first generation spectrometer has been deployed in the field on a mobile laboratory along with a sophisticated 4-tank calibration system. Calibrations are done on an agressive schedule, allowing for the correction of measured isotope ratios to an absolute isotope scale. Distinct isotopic signatures are found for a number of emission sources in the Denver-Julesburg Basin: oil and gas gathering stations, compressor stations and processing plants; a municipal landfill, and dairy/cattle operations. The isotopic signatures are compared with measured ethane/methane ratios. These direct absorption measurements have larger uncertainties than samples measured via gas chromatography-mass spectrometry, but have several advantages over canister sampling methods: individual sources of short duration are easier to isolate; calibrated isotope ratio results are available immediately; replicate measurements on a single source are easily performed; and the number of sources sampled is not limited by canister availability and processing time.

  17. Geometrical and dosimetrical characterization of the photon source using a micro-multileaf collimator for stereotactic radiosurgery

    Science.gov (United States)

    Treuer, H.; Hoevels, M.; Luyken, K.; Hunsche, S.; Kocher, M.; Müller, R.-P.; Sturm, V.

    2003-08-01

    A micro-multileaf collimator (µMLC) for stereotactic radiosurgery is used for determination of the spatial intensity distribution of the photon source of a linear accelerator. The method is based on grid field dose measurements using film dosimetry and is easy to perform. Since the µMLC does not allow 'direct' imaging of the photon source, special software has been developed to analyse grid field measurements. Besides the source-density function, grid field analysis yields the position of the focal spot in the room laser coordinate system of the linear accelerator and the position of the treatment head rotation axis and the inclination angle of the leaf bank. Thus the method can be used for base dosimetry and for quality assurance in radiosurgery using a µMLC.

  18. Geometrical and dosimetrical characterization of the photon source using a micro-multileaf collimator for stereotactic radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Treuer, H [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Hoevels, M [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Luyken, K [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Hunsche, S [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Kocher, M [Department of Radiotherapy, University of Cologne, Cologne (Germany); Mueller, R-P [Department of Radiotherapy, University of Cologne, Cologne (Germany); Sturm, V [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany)

    2003-08-07

    A micro-multileaf collimator ({mu}MLC) for stereotactic radiosurgery is used for determination of the spatial intensity distribution of the photon source of a linear accelerator. The method is based on grid field dose measurements using film dosimetry and is easy to perform. Since the {mu}MLC does not allow 'direct' imaging of the photon source, special software has been developed to analyse grid field measurements. Besides the source-density function, grid field analysis yields the position of the focal spot in the room laser coordinate system of the linear accelerator and the position of the treatment head rotation axis and the inclination angle of the leaf bank. Thus the method can be used for base dosimetry and for quality assurance in radiosurgery using a {mu}MLC.

  19. Kinetic study of the hydrocarbon generation from marine carbonate source rocks characterization of products of gas and liquid hydrocarbon

    Institute of Scientific and Technical Information of China (English)

    GENG Xinhua; GENG Ansong; XIONG Yongqiang; LIU Jinzhong; ZHANG Haizu; ZHAO Qingfang

    2006-01-01

    The kinetic parameters of hydrocarbon generation from the marine carbonate source rocks were determined and calibrated through kinetic simulating experiment. The kinetic parameters of hydrocarbon generation then were extrapolated to geological condition by using the relative software.The result shows that gaseous hydrocarbons (C1, C2,C3, C4-5) were generated in condition of 150℃<T<220℃(1.0%<Ro <3.0% ). Light hydrocarbons (C6-13)and heavy hydrocarbons ( C13+) were generated in condition of 100 ℃<T<170 ℃ (0.5%<Ro<1.5%). A quantitative reference to examine the natural evolution of hydrocarbon of marine carbonate source rocks can be established through the results. It also provides a new method for evaluating the highly mature marine carbonate source rock more reasonably.

  20. Characterizing anthropogenic sources of pollution and their influence on regional air quality and meteorology during the VOCALS-REX experiment

    Science.gov (United States)

    Mena-Carrasco, M.; Carmichael, G. R.; Spak, S.; Molina, L. T.; Saide, P.

    2010-12-01

    During the VOCALS REX campaign multiple anthropogenic sources of aerosol (both primary and secondary) were related to small effective radii of cloud droplets observed both in situ, and from satellite sources. Also enhanced concentrations of secondary pollutants such as ozone and sulfate were observed. Some of these sources come from copper smelters, power plants, and large urban areas. These impacts on the properties of marine stratocumulus is relevant on the region's radiative balance. For this project the contribution of urban, industrial, and power sector emissions will be compared to attribute these to observed values using WRF-Chem using a new Chilean National Emissions Inventory developed for this project. Finally regional ozone formation from Santiago and it's impact to observed enhancements off the coast of Northern Chile will be assessed. Modeled plumes will be compared to satellite observations of anthropogenic impacted clouds. Considering the projected increase of coal power plants in northern Chile, some projected impacts will also be shown.

  1. Nanograting-based compact VUV spectrometer and beam profiler for in-situ characterization of high-order harmonic generation light sources

    Energy Technology Data Exchange (ETDEWEB)

    Kornilov, Oleg; Wilcox, Russell; Gessner, Oliver

    2010-07-09

    A compact, versatile device for VUV beam characterization is presented. It combines the functionalities of a VUV spectrometer and a VUV beam profiler in one unit and is entirely supported by a standard DN200 CF flange. The spectrometer employs a silicon nitride transmission nanograting in combination with a micro-channel plate based imaging detector. This enables the simultaneous recording of wavelengths ranging from 10 nm to 80 nm with a resolution of 0.25 nm to 0.13 nm. Spatial beam profiles with diameters up to 10 mm are imaged with 0.1 mm resolution. The setup is equipped with an in-vacuum translation stage that allows for in situ switching between the spectrometer and beam profiler modes and for moving the setup out of the beam. The simple, robust design of the device is well suited for non-intrusive routine characterization of emerging laboratory- and accelerator-based VUV light sources. Operation of the device is demonstrated by characterizing the output of a femtosecond high-order harmonic generation light source.

  2. Development of bus body rubber profiles with additives from renewable sources: Part I – Additives characterization and processing and cure properties of elastomeric compositions

    International Nuclear Information System (INIS)

    Highlights: • Bus body rubber profiles with additives from renewable sources. • Soybean oil, vulcanization activator from ethanol production and cereal loading filler. • Physical, chemical and thermal characterization of the additives. • Processing and cure properties of elastomeric compositions. • Components commonly used by the rubber industry can be replaced by these additives. - Abstract: The goal of this work was to characterize additives from renewable sources aiming replace the components that are traditionally used by the rubber industry in a formulation with terpolymer of ethylene–propylene–diene (EPDM). Soybean oil (MD600®) was used as a plasticizer. The vulcanization activator (MDECR®) was a sub-product from cellulosic ethanol production, while the loading filler (MDCO®) was obtained from cereals. Firstly, the physical, chemical and thermal properties of these additives were investigated. Thus, a standard composition used for bus body rubber profiles and compositions containing varying proportions of these additives were prepared. The acceleration system was added in a laboratory two-roll mill after the elastomeric compositions were processed in a torque rheometer. The elastomeric compositions were characterized by their cure properties, Mooney viscosities, differential scanning calorimetry (DSC) and X-ray diffraction analysis (XRD). The addition of these additives led to a decrease in the viscosity, work, energy and Mooney viscosity of each composition, thus improving its processability. The curing characteristics of elastomeric compositions were affected by the addition of MD600® and MDECR®, leading to lower vulcanization time, while the cure properties were not affected by the addition of MDCO®

  3. Characterization of blaCMY plasmids and their possible role in source attribution of salmonella enterica serotype typhimurium infections

    Science.gov (United States)

    Salmonella is an important cause of foodborne illness; however, identifying the source of these infections can be difficult. This is especially true for Salmonella serotype Typhimurium, which is found in diverse agricultural niches. Cephalosporins are one of the primary treatment choices for complic...

  4. Assessing Sources of Stress to Aquatic Ecosystems: Using Biomarkers and Bioindicators to Characterize Exodure-Response Profiles of Anthropogenic Activities

    Energy Technology Data Exchange (ETDEWEB)

    Adams, S.M.

    1999-03-29

    Establishing causal relationships between sources of environmental stressors and aquatic ecosystem health if difficult because of the many biotic and abiotic factors which can influence or modify responses of biological systems to stress, the orders of magnitude involved in extrapolation over both spatial and temporal scales, and compensatory mechanisms such as density-dependent responses that operate in populations. To address the problem of establishing causality between stressors and effects on aquatic systems, a diagnostic approach, based on exposure-response profiles for various anthropogenic activities, was developed to help identify sources of stress responsible for effects on aquatic systems at ecological significant levels of biological organization (individual, population, community). To generate these exposure-effects profiles, biomarkers of exposure were plotted against bioindicators of corresponding effects for several major anthropogenic activities including petrochemical , pulp and paper, domestic sewage, mining operations, land-development activities, and agricultural activities. Biomarkers of exposure to environmental stressors varied depending on the type of anthropogenic activity involved. Bioindicator effects, however, including histopathological lesions, bioenergetic status, individual growth, reproductive impairment, and community-level responses were similar among many of the major anthropogenic activities. This approach is valuable to help identify and diagnose sources of stressors in environments impacted by multiple stressors. By identifying the types and sources of environmental stressors, aquatic ecosystems can be more effectively protected and managed to maintain acceptable levels of environmental quality and ecosystem fitness.

  5. Characterization of PM2.5 in Guangzhou, China: uses of organic markers for supporting source apportionment.

    Science.gov (United States)

    Wang, Jingzhi; Ho, Steven Sai Hang; Ma, Shexia; Cao, Junji; Dai, Wenting; Liu, Suixin; Shen, Zhenxing; Huang, Rujin; Wang, Gehui; Han, Yongming

    2016-04-15

    Organic carbon (OC), elemental carbon (EC), and non-polar organic compounds including n-alkanes (n-C14-n-C40), polycyclic aromatic hydrocarbons (PAHs), phthalate esters (PAEs) and hopanes were quantified in fine particulate (PM2.5), which were collected in urban area of Guangzhou, China in winter and summer in 2012/2013. The pollutants levels were well comparable with the data obtained in previous studies in Pearl River Delta (PRD) region but much lower than most northern Chinese megacities. The contribution of EC to PM2.5 and OC/EC ratio suggest that the pollution sources were relatively consistent in GZ between the two seasons. Benzo[a]pyrene (BaP) was the most abundant PAHs, which were 4.9 and 1.0ng/m(3) on average, accounting for 10.7% and 9.1% to the total quantified PAHs in winter and summer, respectively. The total concentrations of PAEs ranged from 289.1 to 2435ng/m(3) and from 102.4 to 1437ng/m(3), respectively, in winter and summer. Di-n-butyl phthalate (DBP) was the most dominant PAEs. The ambient levels of PAEs could be partly attributed to the widespread uses of the household products, municipal garbage compressing, sewage, and external painting material on the building. Source apportionment for OC with chemical mass balance (CMB) model demonstrated coal combustion, vehicle emission, cooking, and secondary organic compounds (SOC) formation were the four major pollution sources. Both of the indices of n-alkanes and diagnostic PAHs ratios support that anthropogenic sources such as vehicle emission and coal combustion were the significant pollution sources with some extents from epicuticular waxes by terrestrial plants. The ratio of hopanes to EC proved the influences from vehicle emission, and displayed a certain degree of the air aging in the Guangzhou ambient air. PMID:26851882

  6. Characterization of Wet and Dry Deposition in the Downwind of Industrial Sources in a Dry Tropical Area

    OpenAIRE

    Singh, Raj K.; Raj M. Agrawal

    2001-01-01

    An atmospheric deposition study was conducted in the downwind of Shaktinagar Thermal Power Plant (STPP), Renusagar Thermal Power Plant (RTPP), and Anpara Thermal Power Plant (ATPP), at Singrauli region, Uttar Pradesh (UP), India to characterize dry and wet deposition in relation to different pollution loading. During the study period, dry and wet depositions and levels of gaseous pollutants (SO2 and NO2) were estimated across the sites. Dry deposition was collected on a monthly basis and wet ...

  7. Characterization of the Primary Starch Utilization Operon in the Obligate Anaerobe Bacteroides fragilis: Regulation by Carbon Source and Oxygen

    OpenAIRE

    Spence, Cheryl; Wells, W. Greg; Smith, C. Jeffrey

    2006-01-01

    The opportunistic pathogen Bacteroides fragilis is a commensal organism in the large intestine, where it utilizes both dietary and host-derived polysaccharides as a source of carbon and energy. In this study, a four-gene operon required for starch utilization was identified. The operon also was found to be oxygen responsive and thus was designated osu for oxygen-induced starch utilization. The first three genes in the operon were predicted to encode outer membrane proteins involved in starch ...

  8. Characterization and properties of NiO films produced by rf magnetron sputtering with oxygen ion source assistance

    International Nuclear Information System (INIS)

    The non-stoichiometric NiO films are deposited on glass substrates at ambient temperature through radio frequency (rf) sputtering of NiO target with oxygen ion source by ion gun at varying ion beam current. An ultra high electrical resistivity is achieved that cannot be detected by four-point probe measurement when the NiO film is deposited without oxygen ion beam assistance. However, it drops significantly to 0.43 Ω-cm when an oxygen ion source is introduced from an ion gun set at a discharge current of 0.22 A. The electrical resistivity of the NiO films decreases continuously to 0.11 Ω-cm as the current is further increased to 0.42 A. The Hall measurements for all NiO films deposited with oxygen ion source assistance show p-type conduction. It is found that the crystallinity of the NiO films degrades when an oxygen ion beam is added during deposition. On the other hand, the transmittance of NiO films deposited without ion source assistance is around 69%. It decreases significantly to 35% when the discharge current of the oxygen ion gun is set at 0.22 A. Upon further increasing the current to 0.28 A, 0.33 A, and 0.42 A, the transmittance of the films drops further to 33%, 28%, and 22%, respectively. - Highlights: • P-type NiO films were achieved by rf sputtering with oxygen ion beam assistance. • Resistivity drops and concentration rises as discharge current of ion gun increases. • Grain size, mobility and transmittance all drop with increasing discharge current

  9. Experimental and numerical characterization of the neutron field produced in the n@BTF Frascati photo-neutron source

    OpenAIRE

    Bedogni, R.; Quintieri, L; Buonomo, B.; Esposito, A.; Mazzitelli, G.; Foggetta, L.; Gomez Ros. J.M.

    2011-01-01

    A photo-neutron irradiation facility is going to be established at the Frascati National Laboratories of INFN on the base of the successful results of the n@BTF experiment. The photoneutron source is obtained by an electron or positron pulsed beam, tunable in energy, current and in time structure, impinging on an optimized tungsten target located in a polyethylene-lead shielding assembly. The resulting neutron field, through selectable collimated apertures at different angles, is released int...

  10. Development and Characterization of Biodegradable Composite Films Based on Gelatin Derived from Beef, Pork and Fish Sources

    OpenAIRE

    Zainal A. Nur Hanani; Eddie Beatty; Yrjo H. Roos; Mick A. Morris; Joseph P. Kerry

    2013-01-01

    The objectives of this study were to develop composite films using various gelatin sources with corn oil (CO) incorporation (55.18%) and to investigate the mechanical and physical properties of these films as potential packaging films. There were increases (p < 0.05) in the tensile strength (TS) and puncture strength (PS) of films when the concentration of gelatin increased. The mechanical properties of these films were also improved when compared with films produced without CO. Conversely, t...

  11. Deposition and characterization of zirconium nitride (ZrN) thin films by reactive magnetron sputtering with linear gas ion source and bias voltage

    International Nuclear Information System (INIS)

    Zirconium nitride thin films have been prepared on stainless steel substrate (304L grade) by reactive cylindrical magnetron sputtering method with Gas Ion Source (GIS) and bias voltage using optimized coating parameters. The structure and surface morphologies of the ZrN films were characterized using X-ray diffraction, atomic microscopy and scanning electron microscopy. The adhesion property of ZrN thin film has been increased due to the GIS. The coating exhibits better adhesion strength up to 10 N whereas the ZrN thin film with bias voltage exhibits adhesion up to 500 mN

  12. Deposition and characterization of zirconium nitride (ZrN) thin films by reactive magnetron sputtering with linear gas ion source and bias voltage

    Energy Technology Data Exchange (ETDEWEB)

    Kavitha, A.; Kannan, R. [Department of Physics, University College of Engineering, Anna University, Dindugal-624622 (India); Subramanian, N. Sankara [Department of Physics, Thiagarajar College of Engineering, Madurai -625015, Tamilnadu (India); Loganathan, S. [Ion Plating, Titan Industries Ltd., Hosur - 635126, Tamilnadu (India)

    2014-04-24

    Zirconium nitride thin films have been prepared on stainless steel substrate (304L grade) by reactive cylindrical magnetron sputtering method with Gas Ion Source (GIS) and bias voltage using optimized coating parameters. The structure and surface morphologies of the ZrN films were characterized using X-ray diffraction, atomic microscopy and scanning electron microscopy. The adhesion property of ZrN thin film has been increased due to the GIS. The coating exhibits better adhesion strength up to 10 N whereas the ZrN thin film with bias voltage exhibits adhesion up to 500 mN.

  13. Open Source Laser Polymer Welding System: Design and Characterization of Linear Low-Density Polyethylene Multilayer Welds

    Directory of Open Access Journals (Sweden)

    John J. Laureto

    2016-07-01

    Full Text Available The use of lasers to weld polymer sheets provides a means of highly-adaptive and custom additive manufacturing for a wide array of industrial, medical, and end user/consumer applications. This paper provides an open source design for a laser polymer welding system, which can be fabricated with low-cost fused filament fabrication and off-the-shelf mechanical and electrical parts. The system is controlled with free and open source software and firmware. The operation of the machine is validated and the performance of the system is quantified for the mechanical properties (peak load and weld width of linear low density polyethylene (LLDPE lap welds manufactured with the system as a function of linear energy density. The results provide incident laser power and machine parameters that enable both dual (two layers and multilayer (three layers while welding only two sheets polymer welded systems. The application of these parameter sets provides users of the open source laser polymer welder with the fundamental requirements to produce mechanically stable LLDPE multi-layer welded products, such as heat exchangers.

  14. Detection and Molecular Characterization of Potentially Pathogenic Free-living Amoebae from Water Sources in Kish Island, Southern Iran.

    Science.gov (United States)

    Niyyati, Maryam; Lasgerdi, Zohreh; Lorenzo-Morales, Jacob

    2015-01-01

    Amoebic keratitis, a sight-threatening corneal infection, mainly occurs in contact lens wearers who wash their eyes with tap water. The present research was conducted to identify the occurrence of potentially pathogenic free-living amoebae (FLA) in tap water sources on Kish Island, a tourist region in Iran. Amoebae were detected using a culture-enriched method and by polymerase chain reaction (PCR)/sequencing of the diagnostic fragment 3 region of the 18S rRNA gene of Acanthamoeba. In the case of other free-living amoebae species, PCR/sequencing analysis of the 18S rDNA was conducted. Results of this study showed the presence of Acanthamoeba belonging to T3, T4, T5, and T11 genotypes in tap water sources. Additionally, Vermamoebae vermiformis was detected in three water samples. This is the first report of the Acanthamoeba genotypes T3, T4, T5, and T11 and V. vermiformis species in tap water sources in a tourist region in Iran.

  15. Mössbauer and Raman spectroscopy characterization of concretes used in the conditioning of spent radioactive sources

    Energy Technology Data Exchange (ETDEWEB)

    Monroy-Guzman, F., E-mail: fabiola.monroy@inin.gob.mx; González-Neri, M.; González-Díaz, R. C.; Ortíz-Arcivar, G.; Corona-Pérez, I. J. [Instituto Nacional de Investigaciones Nucleares. Carretera México-Toluca s/n, La Marquesa, Ocoyoacac (Mexico); Nava, N. [Instituto Mexicano del Petroleo (Mexico); Cabral-Prieto, A.; Escobar-Alarcón, L. [Instituto Nacional de Investigaciones Nucleares. Carretera México-Toluca s/n, La Marquesa, Ocoyoacac (Mexico)

    2015-06-15

    Spent radioactive sources are considered a type of radioactive waste which must be stored properly. These sources are usually conditioned in concrete that functions as shield and physical barrier to prevent the potential migration of radionuclides, and must have suitable properties: mechanical, thermal or irradiation resistance. Concretes used in the conditioning of spent radioactive source in Mexico were tested, preparing concrete test specimens with Portland cement CPC 30RS EXTRA CEMEX and aggregates, and subjected to compression strength, γ-ray-irradiation and thermal resistance assays and subsequently analyzed by Mössbauer and Raman Spectroscopies as well as by Scanning Electron Microscopy, in order to correlate the radiation and temperature effects on the compressive strengths, the oxidation states of iron and the structural features of the concrete. Iron was found in the concrete in Fe {sup 2+} and Fe {sup 3+} in the tetrahedral (T) and two octahedral positions (O1, O2). Radiolysis of water causes the dehydratation (200-600 kGy) and rehydratation (1000-10000 kGy) of calcium silicate hydrates (C-S-H) and ferric hydrate phases in concretes and structural distortion around the iron sites in concretes. The compressive strength of concretes are not significantly affected by γ-radiation or heat.

  16. First hydrogen operation of NIO1: Characterization of the source plasma by means of an optical emission spectroscopy diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Barbisan, M., E-mail: marco.barbisan@igi.cnr.it; Baltador, C.; Zaniol, B.; Pasqualotto, R.; Serianni, G. [Consorzio RFX (CNR, ENEA, INFN, Univ. of Padua, Acciaierie Venete SpA), C.so Stati Uniti 4, 35127 Padova (Italy); Cavenago, M. [INFN-LNL, v.le dell’Università 2, I-35020 Legnaro (Italy); Fantz, U.; Wünderlich, D. [Max-Planck Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching (Germany); Vialetto, L. [Università degli Studi di Padova, Via 8 Febbraio, 2, 35122 Padova (Italy)

    2016-02-15

    NIO1 (Negative Ion Optimization 1) is a compact and flexible radio frequency H{sup −} ion source, developed by Consorzio RFX and INFN-LNL. The aim of the experimentation on NIO1 is the optimization of both the production of negative ions and their extraction and beam optics. In the initial phase of its commissioning, NIO1 was operated with nitrogen, but now the source is regularly operated also with hydrogen. To evaluate the source performances, an optical emission spectroscopy diagnostic was installed. The system includes a low resolution spectrometer in the spectral range of 300-850 nm and a high resolution (50 pm) one, to study, respectively, the atomic and the molecular emissions in the visible range. The spectroscopic data have been interpreted also by means of a collisional-radiative model developed at IPP Garching. Besides the diagnostic hardware and the data analysis methods, the paper presents the first plasma measurements across a transition to the full H mode, in a hydrogen discharge. The characteristic signatures of this transition in the plasma parameters are described, in particular, the sudden increase of the light emitted from the plasma above a certain power threshold.

  17. Geochemical characterization of lower Toarcian source rocks from NW Germany: interpretation of aromatic and saturated hydrocarbons in relation to depositional environment and maturation effects

    Energy Technology Data Exchange (ETDEWEB)

    Radke, M.; Schaefer, R.G. [Institut fuer Erdol und Organische Geochemie, Juelich (Germany); Vriend, S.P. [University of Utrecht (Netherlands). Institute of Earth Sciences

    2001-07-01

    The characterization of crude oils in terms of source rock facies and depositional environment, as well as their maturity and alteration stage, is a crucial element in exploration studies. The present contribution has implications for oil-oil and oil-source rock correlations. In the past, numerous parameters have been used for this purpose most of which are based on the analysis of saturated and aromatic hydrocarbons (including sulphur aromatics) and also on stable isotope signatures and elemental compositions. Recently, molecular indicators based on dibenzothiophene (DBT), phenanthrene (PHE) and their methyl derivatives methyldlbenzothiophene (MDBT) an methylphenanthrene, as well as pristane (PRI) and phytane (PHY), have also been proposed (Hughes et al, 1995). These studies have attempted to infer a crude oil's source rock facies and lithology, and to classify the source rock's depositional environment. In the present study, the above compounds have been quantified by solvent extraction, liquid chromatography and capillary gas chromatography in 98 core samples of the Lower Toarcian Posidonia Shale Formation, a source rock in NW Germany. Most samples cored between depths of 7m and 70 m, came from the Hils Half-Graben in the Lower Saxony Basin. With a few exceptions from on borehole, the samples were unweathered maris or calcareous shales. The rocks contained mainly marine organic matter (Type 1 kerogen), the thermal maturity of which ranged from early mature to postmature (corresponding to 0.48-1.44% mean vitrinite reflectance), therefore encompassing the range over which effective petroleum generation had occurred. We found that the influence of organic matter type and maturity on the molecular distributions of the above compounds were not obvious when interpreted in term of a DBT/PHE vs PRI/PHY diagram. However, Principal Component Analysis (PCA) of our data-set showed that alkylphenanthren concentrations are strongly controlled by maturity, while the

  18. New method for selection and characterization of single-source events in Ni+Ni collisions at 32 A.MeV

    International Nuclear Information System (INIS)

    The study of heavy ion collisions, with the help of such efficient multi-detectors as INDRA, has shown the persistence of reactions leading to single-source events, up to bombarding energies higher than the Fermi one. These events could help characterizing an expected phase transition in nuclear matter. Whatever interesting they may be, the single-source events correspond to a small part of the total cross section, which makes them difficult to isolate and therefore to analyze. That is why different selection means have been tested - thanks to the 'Simon' event generator - on a simulated Ni + Ni at 32 A·MeV sample, before any application to the INDRA experimental data. As the known methods based on global variables did not prove effective, a set of new 4-dimensional quantities has been built, whose main advantage lies in a better description of physical events. From a Discriminant Analysis performed on 625 of these new 'moments' proceeds a highly discriminant variable, called D625. The experimental cross section associated with D625-selected single-source events amounts to 170 mb at 32 A·MeV. Such quasi-fusion events are shown to disappear at about 60 A·MeV. As regards the deexcitation mode of the 32 A·MeV Ni + Ni single-source events, an extensive experimental study and comparisons of the data with two reference models seem to confirm the hypothesis of a transition between fusion-evaporation and simultaneous multifragmentation mechanisms. (author)

  19. Reflection seismic imaging of the upper crystalline crust for characterization of potential repository sites: Fine tuning the seismic source

    International Nuclear Information System (INIS)

    SKB is currently carrying out studies to determine which seismic techniques, and how, they will be used for investigations prior to and during the building of a high-level nuclear waste repository. Active seismic methods included in these studies are refraction seismics, reflection seismics, and vertical seismic profiling (VSP). The main goal of the active seismic methods is to locate fracture zones in the crystalline bedrock. Plans are to use longer reflection seismic profiles (3.4 km) in the initial stages of the site investigations. The target depth for these seismic profiles is 100-1500 m. Prior to carrying out the seismic surveys over actual candidate waste repository sites it has been necessary to carry out a number of tests to determine the optimum acquisition parameters. This report constitutes a summary of the tests carried out by Uppsala University. In addition, recommended acquisition and processing parameters are presented at the end of the report. A major goal in the testing has been to develop a methodology for acquiring high-resolution reflection seismic data over crystalline rock in as a cost effective manner as possible. Since the seismic source is generally a major cost in any survey, significant attention has been given to reducing the cost of the source. It was agreed upon early in the study that explosives were the best source from a data quality perspective and, therefore, only explosive source methods have been considered in this study. The charge size and shot hole dimension required to image the upper 1-1.5 km of bedrock is dependent upon the conditions at the surface. In this study two types of shot hole drilling methods have been employed depending upon whether the thickness of the loose sediments at the surface is greater or less than 0.5 m. The charge sizes and shot hole dimensions required are: Loose sediment thickness less than 0.5 m: 15 g in 90 cm deep 12 mm wide uncased shot holes. Loose sediment thickness greater than 0.5 m: 75 g

  20. Characterizing the ozone formation potential of agricultural sources in California's San Joaquin Valley: A computational and experimental approach

    Science.gov (United States)

    Howard, Cody Jerome

    The global pattern of expanding urban centers and increasing agricultural intensity is leading to more frequent interactions between air pollution emissions from urban and agricultural sources. The confluence of these emissions that traditionally have been separated by hundreds of kilometers is creating new air quality challenges in numerous regions across the United States. An area of particular interest is California's San Joaquin Valley (SJV), which has an agricultural output higher than many countries, a rapidly expanding human population, and ozone concentrations that are already higher than many dense urban areas. New regulations in the SJV restrict emissions of reactive organic gases (ROG) from animal sources in an attempt to meet Federal and State ozone standards designed to protect human health. A transportable "smog" chamber was developed and tested to directly measure the ozone formation potential of a variety of agricultural emissions in representative urban and rural atmospheres. After validation of the experimental procedure, four animal types were examined: beef cattle, dairy cattle, swine, and poultry, as well as six commonly used animal feeds: cereal silage (wheat grain and oat grain), alfalfa silage, corn silage, high moisture ground corn, almond shells, almond hulls, and total mixed ration. The emitted ROG composition was also measured so that the theoretical incremental reactivity could be calculated for a variety of atmospheres and directly compared with the measured ozone formation potential (OFP) under the experimental conditions. A computational model was created based on a modified form of the Caltech Atmospheric Chemistry Mechanism and validated against experimental results. After validation, the computational model was used to predict OFP across a range of NOx and ROG concentrations. The ROG OFP measurements combined with adjusted agricultural ROG emissions inventory estimates were used to predict the actual ozone production in the SJV

  1. Preparation and characterization of poly-pyrrole thin films functionalized by ion exchanger groups. Application to preparation of alpha sources

    International Nuclear Information System (INIS)

    After having outlined that dosing methods still present problems related to chemical separations techniques used before radioactivity measurements, and to spectrometric methods, this research thesis proposes the study of a new method of fabrication of a radioactive source. This method comprises the fabrication of a chemically reactive thin film by electro-polymerization, and the incorporation of actinides in the deposit by ion exchange. In this case, the deposit thickness could be controlled and the material transfer chemical mechanisms could be predicted and controlled

  2. Design, fabrication, and characterization of a solenoid system to generate magnetic field for an ECR proton source

    Indian Academy of Sciences (India)

    S K Jain; P A Naik; P R Hannurkar

    2010-08-01

    Solenoid coils with iron jacket (electromagnets) have been designed and developed for generation and confinement of the plasma produced by an electron cyclotron resonance source operating at 2450 MHz frequency. The magnetic field configurations designed using the solenoid coils are off-resonance, mirror, and flat, satisfying electron cyclotron resonance condition along the axis of the plasma chamber. 2D Poisson software was used for designing. Details of design, fabrication, and magnetic field mapping of the solenoid coils are presented in this paper.

  3. Ab initio molecular orbital characterization of dimethyl group-III azides as sources for photolytic production of free radical beams

    International Nuclear Information System (INIS)

    Use of a beam of biradicaloid such as dialkyl group-III nitrene produced by the method of photodissociation of energetic compound beams (PDECB) is expected to be advantageous to the low-temperature thin-film growth of stoichiometric group-III nitride. Through the clarification of fundamental processes involved in pyrolysis as well as photolysis of dimethylgallium azide [(CH3)2GaN3], dimethylaluminum azide [(CH3)2AlN3], and dimethylboron azide [(CH3)2BN3] based on post-self-consistent field ab initio molecular orbital methods, we discuss the suitability of these possible source compounds for the production of beams of dimethylgalliumnitrene [(CH3)2GaN], dimethylaluminumnitrene [(CH3)2AlN], and dimethylboronnitrene [(CH3)2BN] by the PDECB method. The theoretical results suggested that (CH3)2GaN3 is a promising PDECB source material in that this molecule possesses the nature of unimolecular metastable dye

  4. Characterization of the dissolved organic matter in sewage effluent of sequence batch reactor: the impact of carbon source

    Institute of Scientific and Technical Information of China (English)

    Jin GUO; Feng SHENG; Jianhua GUO; Xiong YANG; Mintao MA; Yongzhen PENG

    2012-01-01

    Dissolved organic matter (DOM) transforma- tion in sequence batch reactor (SBR) fed with carbon sources of different biodegradability was investigated. During the biologic degradation process, the low mole- cular weight (MW) fraction (〈 1 kDa) gradually decreased, while the refractory compounds with higher aromaticity were aggregated. Size exclusion chromatogra- phy (SEC) and fluorescence of excitation emission matrices (EEM) demonstrated that more biopolymers (polysaccharides or proteins) and humic-like substances were presented in the extracellular polymeric substance (EPS) extracted from the SBR fed with sodium acetate or glucose, while the EPS from SBR fed with slowly biodegradable dissolved organic carbon (DOC) substrate- starch had relatively less biopolymers. Comparing the EfOM in sewage effluent of three SBRs, the effluent from SBR fed with starch is more aromatic. Organic carbon with MW 〉 1 kDa as well as the hydrophobic fraction in DOM gradually increased with the carbon sources changing from sodium acetate to glucose and starch. The DOC fractiona- tion and the EEM all demonstrated that EfOM from the effluent of the SBR fed with starch contained more fulvic acid-like substances comparing with the SBR fed with sodium acetate and glucose.

  5. Euphorbia tirucalli L.–Comprehensive Characterization of a Drought Tolerant Plant with a Potential as Biofuel Source

    Science.gov (United States)

    Hastilestari, Bernadetta Rina; Mudersbach, Marina; Tomala, Filip; Vogt, Hartmut; Biskupek-Korell, Bettina; Van Damme, Patrick; Guretzki, Sebastian; Papenbrock, Jutta

    2013-01-01

    Of late, decrease in mineral oil supplies has stimulated research on use of biomass as an alternative energy source. Climate change has brought problems such as increased drought and erratic rains. This, together with a rise in land degeneration problems with concomitant loss in soil fertility has inspired the scientific world to look for alternative bio-energy species. Euphorbia tirucalli L., a tree with C3/CAM metabolism in leaves/stem, can be cultivated on marginal, arid land and could be a good alternative source of biofuel. We analyzed a broad variety of E. tirucalli plants collected from different countries for their genetic diversity using AFLP. Physiological responses to induced drought stress were determined in a number of genotypes by monitoring growth parameters and influence on photosynthesis. For future breeding of economically interesting genotypes, rubber content and biogas production were quantified. Cluster analysis shows that the studied genotypes are divided into two groups, African and mostly non-African genotypes. Different genotypes respond significantly different to various levels of water. Malate measurement indicates that there is induction of CAM in leaves following drought stress. Rubber content varies strongly between genotypes. An investigation of the biogas production capacities of six E. tirucalli genotypes reveals biogas yields higher than from rapeseed but lower than maize silage. PMID:23658836

  6. Development and characterization of an improved Ir--0.3% W alloy for space radioisotopic heat sources

    International Nuclear Information System (INIS)

    An Ir--0.3% W alloy has been doped with minor alloying additions to develop an improved cladding material for space radioisotopic heat sources operating at temperatures to 14500C. Tensile tests of a series of doped alloys at slow strain rates indicated that the DOP-4 alloy containing 40 Al, 30 Th, 80 Fe, 10 Ni, and 75 Rh ppm was most resistant to the brittle fracture associated with grain-boundary separation. In addition, the DOP-4 dopants raise the recrystallization temperature, and retard grain growth at high temperatures. The impact properties of DOP-4 and undoped Ir--0.3 W alloys were determined as a function of grain size, test temperature, impact velocity and long-term heat treatment. All the results indicate that the impact properties of the DOP-4 alloy are far superior to those of the undoped alloy. The improvement results from the segregation of beneficial dopant(s) (such as thorium) to grain boundaries and precipitation of second-phase particles. The development of the DOP-4 alloy greatly improves the safety margin of the Multi-Hundred-Watt heat sources to be used in a space probe to Jupiter and Saturn in 1977

  7. Palynofacies characterization for hydrocarbon source rock evaluation in the Subathu Formation of Marhighat, Sirmaur district, Himachal Pradesh

    Indian Academy of Sciences (India)

    O P Thakur; N N Dogra

    2011-10-01

    This paper deals with the hydrocarbon source rock evaluation of the Subathu Formation exposed at Marhighat on Sarahan–Narag road in Sirmaur district of Himachal Pradesh. Hydrocarbon potential of these sediments is estimated on the basis of palynofacies analysis and thermal alteration index (TAI) values based on the fossil spores/pollen colouration. The analyses are based on the classification and hydrocarbon generation potential of plant derived dispersed organic matter present in the sediments. The palynofacies analysis of Subathu Formation in the area reveal moderate to rich organic matter, with amorphous organic matter constituting the bulk of the total organic matter, followed by charcoal, biodegraded organic matter, fungal remains, spores/pollen and structured terrestrial organic matter. The TAI value for the organic matter in these sediments has been ascertained as 3.00. A dominance of the sapropelic facies (amorphous organic matter) and the measured TAI values for the Subathu sediments in the Marhighat area suggests a good source-rock potential for the hydrocarbon generation.

  8. Characterization and fingerprinting of soil and groundwater contamination sources around a fuel distribution station in Galicia (NW Spain).

    Science.gov (United States)

    Balseiro-Romero, María; Macías, Felipe; Monterroso, Carmen

    2016-05-01

    Soil and groundwater contamination around a fuel distribution station in Tomiño (NW Spain) was evaluated. For this purpose, top and subsoil (up to 6.4 m) and groundwater were sampled around the station, approximately in a 60-m radius. Samples were analysed by HS-SPME-GC-MS to identify and quantify volatile fuel organic compounds (VFOC) (MTBE, ETBE and BTEX) and diesel range organics (DRO). Analysis and fingerprinting data suggested that the contamination of soil and groundwater was provoked by a fuel leak from underground storage tanks. This was reflected by hydrocarbon indices and principal component analysis, which discriminated a direct source of contamination of the subsoil samples around the station. The contaminants probably migrated from tank nearby soils to surrounding soils and leached to groundwater, following a SW direction. Irrigation with contaminated groundwater provoked a severe contamination of topsoils, which were enriched with the lightest components of gasoline and diesel. Fingerprinting also revealed the continuity of the leak, reflected by the presence of volatiles in some samples, which principally appeared in fresh leaks. MTBE was detected in a very high concentration in groundwater samples (up to 690 μg L(-1)), but it was not detected in fresh gasoline. This also evidenced an old source of contamination, probably starting in the mid-1990s, when the use of MTBE in gasoline was regulated.

  9. Characterization and fingerprinting of soil and groundwater contamination sources around a fuel distribution station in Galicia (NW Spain).

    Science.gov (United States)

    Balseiro-Romero, María; Macías, Felipe; Monterroso, Carmen

    2016-05-01

    Soil and groundwater contamination around a fuel distribution station in Tomiño (NW Spain) was evaluated. For this purpose, top and subsoil (up to 6.4 m) and groundwater were sampled around the station, approximately in a 60-m radius. Samples were analysed by HS-SPME-GC-MS to identify and quantify volatile fuel organic compounds (VFOC) (MTBE, ETBE and BTEX) and diesel range organics (DRO). Analysis and fingerprinting data suggested that the contamination of soil and groundwater was provoked by a fuel leak from underground storage tanks. This was reflected by hydrocarbon indices and principal component analysis, which discriminated a direct source of contamination of the subsoil samples around the station. The contaminants probably migrated from tank nearby soils to surrounding soils and leached to groundwater, following a SW direction. Irrigation with contaminated groundwater provoked a severe contamination of topsoils, which were enriched with the lightest components of gasoline and diesel. Fingerprinting also revealed the continuity of the leak, reflected by the presence of volatiles in some samples, which principally appeared in fresh leaks. MTBE was detected in a very high concentration in groundwater samples (up to 690 μg L(-1)), but it was not detected in fresh gasoline. This also evidenced an old source of contamination, probably starting in the mid-1990s, when the use of MTBE in gasoline was regulated. PMID:27080856

  10. The onset of the Little Ice Age in Andalusia (southern Spain: detection and characterization from documentary sources

    Directory of Open Access Journals (Sweden)

    F. S. Rodrigo

    Full Text Available In this work the onset of the "Little Ice Age" period in Andalusia (southern Spain is analysed from documentary data, focusing attention on the evolution of the climate during the 16th and 17th centuries. It is shown that changes in the rainfall regime have been more important than those in the temperature in studying the Andalusian climate change. Analysis of the total annual precipitation is carried out by codifying the documentary data and establishing an ordinal index. Several statistical methods are used to detect and characterize climate changes in the region. The results suggest a fluctuating evolution, without trends or abrupt changes, with a prevailing wet period from 1550 to 1650 AD. Cycles of ~17, 3.5 and 2.1 years are detected. Some possible causal mechanisms are suggested.

  11. Characterization of myrtle seed (Myrtus communis var. baetica as a source of lipids, phenolics, and antioxidant activities

    Directory of Open Access Journals (Sweden)

    Wissem Aidi Wannes

    2016-04-01

    Full Text Available This study aimed to characterize the chemical composition and antioxidant activity of the oil and the methanolic extract of Myrtus communis var. baetica seed. The oil yield of myrtle seed was 8.90%, with the amount of neutral lipid, especially triacylglycerol, being the highest, followed by phospholipids and glycolipids. Total lipids and all lipid classes were rich in linoleic acid. The content of total phenols, flavonoids, tannins, and proanthocyanidins of the methanolic extract and the oil from myrtle seed was determined using spectrophotometric methods. Antioxidant activities of the oil and the methanolic extract from myrtle seed were evaluated using 1,1-diphenyl-2-picrylhydrazyl radical scavenging, β-carotene–linoleic acid bleaching, and reducing power and metal chelating activity assays. In all tests, the methanolic extract of myrtle seed showed better antioxidant activity than oil. This investigation could suggest the use of myrtle seed in food, industrial, and biomedical applications for its potential metabolites and antioxidant abilities.

  12. Synthesis and characterizations of nanoscale single crystal GaN grown by ion assisted gas source MBE

    Science.gov (United States)

    Cui, Bentao; Cohen, P. I.

    2004-03-01

    Nanoscale patterns could be induced by ion bombardment [1, 2]. In this study, an in-situ real time light scattering technique, combined with Reflection High Energy Electron Diffraction (RHEED), were used to study the surface morphology evolution during the ion beam assisted growth of GaN in a gas source MBE system. Ga was provided by a thermal effusion cell. Ammonia was used as the nitrogen source. A hot-filament Kaufman ion source was used to supply sub-KeV ion beams. Sapphire and MOCVD GaN templates were used as the substrates. A custom-designed Desorption Mass Spectrometer (DMS) was used to calibrate the growth temperature and determine the growth rate. Before growing GaN, the sapphire substrates were pretreated in an ion flux and then annealed for cleaning. The sapphire surface was then nitrided in ammonia at 1100K for about 10 min. After nitridation, a thin GaN buffer layer was prepared by a sequence of adsorption and annealing steps. During the growth, the short-range surface morphology and film quality were monitored in situ by RHEED. In a real-time way, the long-range surface morphology was monitored in-situ by light scattering technique. Photodiode array detector and CCD camera were used to record the reflected light scattering intensity and spectra profile respectively. Periodical patterns, such as ripple, have been observed during ion bombardment on GaN with or without growth. A linear theory (from Bradley and Harper 1988 [3]) has been modified to explain the dependence of ripple wavelength on ion species and ion energy. Partially supported by the National Science Foundation and the Air Force Office of Scientific Research. [1]. J. Erlebacher, M. J. Aziz, E. Chason, M. B. Sinclair, and J. A. Floro, Phys. Rev. Lett. 82, 2330 (1998); J. Erlebacher, M. J. Aziz, E. Chason, M. B. Sinclair, and J. A. Floro, Phys. Rev. Lett. 84, 5800 (2000). [2]. S. Facsko, T. Dekorsy, C. Koerdt, C. Trappe, H. Kurz, A. Vogt et al.. Science 285, 1551 (1999). [3]. R. M. Bradley

  13. An inter-comparison of PM2.5 at urban and urban background sites: Chemical characterization and source apportionment

    Science.gov (United States)

    Cesari, D.; Donateo, A.; Conte, M.; Merico, E.; Giangreco, A.; Giangreco, F.; Contini, D.

    2016-06-01

    A measurement campaign was performed between 04/03/2013 and 17/07/2013 for simultaneous collection of PM2.5 samples in two nearby sites in southeastern Italy: an urban site and an urban background site. PM2.5 at the two sites were similar; however, the chemical composition and the contributions of the main sources were significantly different. The coefficients of divergence (CODs) showed spatial heterogeneity of EC (higher at the urban site because of traffic emissions) and of all metals. Major ions (NH4+, Na+, and SO42 -) and OC had low CODs, suggesting a homogeneous distribution of sea spray, secondary sulfate, and secondary organic matter (SOM = 1.6*OCsec, where OCsec is the secondary OC). The strong correlations between Na+ and Cl-, and the low Cl-/Na+ ratios, suggested the presence of aged sea spray with chloride depletion (about 79% of Cl-) and formation of sodium nitrate at both sites. In both sites, the non-sea-salt sulfate was about 97% of sulfate, and the strong correlation between SO42 - and NH4+ indicated that ammonium was present as ammonium sulfate. However, during advection of Saharan Dust, calcium sulfate was present rather than ammonium sulfate. The source apportionment was performed using the Positive Matrix Factorization comparing outputs of model EPA PMF 3.0 and 5.0 version. Six aerosol sources were identified at both sites: traffic, biomass burning, crustal-resuspended dust, secondary nitrate, marine aerosol, and secondary sulfate. The PMF3.0 model was not completely able, in these sites, to separate marine contribution from secondary nitrate and secondary sulfate from OC, underestimating the marine contribution and overestimating the secondary sulfate with respect to stoichiometric calculations. The application of specific constraints on PMF5.0 provided cleaner profiles, improving the comparison with stoichiometric calculations. The seasonal trends revealed larger biomass burning contributions during the cold period at both sites due to

  14. Characterization and source identification of trace elements in airborne particulates at urban and suburban atmospheres of Tabriz, Iran.

    Science.gov (United States)

    Gholampour, Akbar; Nabizadeh, Ramin; Hassanvand, Mohammad Sadegh; Taghipour, Hasan; Rafee, Mohammad; Alizadeh, Zahra; Faridi, Sasan; Mahvi, Amir Hossein

    2016-01-01

    Concentration of particulate matter (PM10 and total suspended particulate (TSP)) and their elemental constituents were measured to identify the major sources of elements in urban and industrial suburban sites in Tabriz, Iran, from September 2012 to June 2013. TSP and PM10 samples were collected using high-volume samplers. Concentrations of 31 elements in aerosols and crustal soil were determined by ICPMS. The most abundant detected metals in the urban sampling sites were Al (217.5-4019.9 ng m(-3)), Fe (272.5-7658.0 ng m(-3)), Pt (4.7-1994.4 ng m(-3)), and P (13.6-2054.8 ng m(-3) (for TSP and Al (217.6-3687.3 ng m(-3)), Fe (197.1-3724.9 ng m(-3)), Pt (65.9-2054.5 ng m(-3)), and P (11.0-756.6 ng m(-3)( for PM10. In the suburban sampling site, the most abundant detected metals were Al (2083.0-9664.0 ng m(-3)), Fe (360.0-7221.5 ng m(-3)), P (229.4-870.5 ng m(-3)), and Ti (137.3-849.7 ng m(-3)) for TSP and Al (218.5-4179.6 ng m(-3)), Fe (106.3-2005.1 ng m(-3)), P (251.9-908.4 ng m(-3)), and Ba (10.6-584.9 ng m(-3)) for PM10. For the crustal soil, the most abundant detected elements included Al (60,088-60,694 ppm), Fe (19,886-20,474 ppm), Ti (894-3481 ppm), and Si (365-4246 ppm). Key emission sources were identified, and the concentrations contributed from individual sources were estimated. Enrichment factor (EF) explaining a preponderance of the variance in the data was applied to the datasets. EF calculations revealed that non-crustal trace elements were more enriched in the urban than suburban sampling sites. Results of the factor analysis on the elements showed that emissions from road traffic (involving oil and fuel combustions by vehicles, platinum group elements from vehicle exhaust, and resuspension of particulate matter from polluted soil) and construction dust from nearby construction sites and electricity generation plant were the major contributors of anthropogenic metals at ambient atmosphere in Tabriz. Results of this study elucidated the need for

  15. Technical memorandum on data needs and sources to characterize LLW from the Midwest Compact Region (Deliverable 2A)

    International Nuclear Information System (INIS)

    In order to make wise choices in developing a Regional Management Plan for low-level radioactive waste (LLW) from the Midwest Region, a number of key parameters of the LLW generated in the region must be determined. Estimates must be made of the overall volume of waste that is currently generated, who the generators are, and where the waste will originate. The volume of waste should be further broken down into distinct kinds of material such as trash, ion exchange resins, liquid scintillation vials, etc., and into NRC waste classes as prescribed in 10CFR61. These factors will influence the kinds of treatment and disposal facilities to be employed by the Midwest Low-Level Radioactive Waste Commission and where these facilities may be sited. This memorandum describes the needs for data on low-level wastes in the Midwest and the sources that will be tapped to gather that data

  16. Characterization of nuclear sources from neutron-neutron, proton-proton and neutron-proton correlation functions

    Energy Technology Data Exchange (ETDEWEB)

    Ghetti, R. E-mail: roberta.ghetti@kosufy.lu.se; Martensson, J.; Colonna, N.; Helgesson, J.; Jakobsson, B.; De Filippo, E.; Tagliente, G.; Lanzano, G.; Pantaleo, A.; Bellini, V.; Anzalone, A.; Carlen, L.; Cavallaro, S.; Celano, L.; D' Erasmo, G.; Di Santo, D.; Fiore, E.M.; Fokin, A.; Geraci, M.; Giustolisi, F.; Kuznetsov, A.; Mahboub, D.; Palazzolo, F.; Palomba, M.; Paticchio, V.; Riera, G.; Sperduto, M.L.; Sutera, C.; Urrata, M

    2000-07-03

    Two-neutron, two-proton and neutron-proton correlation functions have been measured simultaneously for the E/A=45 MeV {sup 58} Ni + {sup 27} Al reaction. Calculations from a statistical model have been compared to singles energy spectra as well as to total and gated correlation functions. This imposes very strong constraints on the model parameters. The use of directionally gated correlation functions helps to disentangle space and time information. Values of Gaussian radii, emission lifetimes, initial temperatures, source velocities and flow velocities are extracted. Correlation functions gated on total momentum of the nucleon pairs suggest that more energetic particles are emitted on a fast time scale ( < 100 fm / c ) and that the fraction of pre-equilibrium to equilibrium emission is larger for protons than for neutrons.

  17. Characterization of the ZnO thin film prepared by single source chemical vapor deposition under low vacuum condition

    Institute of Scientific and Technical Information of China (English)

    DENG; Hong(邓宏); B.; GONG; A.; J.; Petrella; J.; J.; Russell; R.; N.; Lamb

    2003-01-01

    A novel technique is developed for growing high quality ZnO thin films by means of single source chemical vapor deposition (SS CVD) under low vacuum conditions with the precursor of zinc carbamate Zn4O(CO2Net2)6. SEM, AFM and XRD studies show that the resultant thin films have high density, smooth surface, uniform polycrystalline structure and excellent c-axis orientation. XPS investigation indicates that the ZnO films are free of decomposed precursor residues in the bulk. Careful quantitative XPS analysis reveals that the ZnO films are stoichiometric with O/Zn atomic ratio very close to that of ZnO single crystal.

  18. Development and Characterization of Biodegradable Composite Films Based on Gelatin Derived from Beef, Pork and Fish Sources

    Directory of Open Access Journals (Sweden)

    Zainal A. Nur Hanani

    2013-01-01

    Full Text Available The objectives of this study were to develop composite films using various gelatin sources with corn oil (CO incorporation (55.18% and to investigate the mechanical and physical properties of these films as potential packaging films. There were increases (p < 0.05 in the tensile strength (TS and puncture strength (PS of films when the concentration of gelatin increased. The mechanical properties of these films were also improved when compared with films produced without CO. Conversely, the water barrier properties of composite films decreased (p < 0.05 when the concentration of gelatin in composite films increased. Comparing with pure gelatin films, water and oxygen barrier properties of gelatin films decreased when manufactured with the inclusion of CO.

  19. Characterization of nuclear sources from neutron-neutron, proton-proton and neutron-proton correlation functions

    CERN Document Server

    Ghetti, R; Colonna, N; Helgesson, J; Jakobsson, B; De Filippo, E; Tagliente, G; Lanzanò, G; Pantaleo, A; Bellini, V; Anzalone, A; Carlén, L; Cavallaro, S; Celano, L; D'Erasmo, G; Di Santo, D; Fiore, E M; Fokin, A; Geraci, M; Giustolisi, F; Kuznetsov, A; Mahboub, D; Palazzolo, F; Palomba, M; Paticchio, V; Riera, G; Sperduto, M L; Sutera, C; Urrata, M

    2000-01-01

    Two-neutron, two-proton and neutron-proton correlation functions have been measured simultaneously for the E/A=45 MeV sup 5 sup 8 Ni + sup 2 sup 7 Al reaction. Calculations from a statistical model have been compared to singles energy spectra as well as to total and gated correlation functions. This imposes very strong constraints on the model parameters. The use of directionally gated correlation functions helps to disentangle space and time information. Values of Gaussian radii, emission lifetimes, initial temperatures, source velocities and flow velocities are extracted. Correlation functions gated on total momentum of the nucleon pairs suggest that more energetic particles are emitted on a fast time scale ( < 100 fm / c ) and that the fraction of pre-equilibrium to equilibrium emission is larger for protons than for neutrons.

  20. Characterization of the Sources and Concentrations of Formaldehyde and other volatile organic compounds in four new manufactured houses

    Energy Technology Data Exchange (ETDEWEB)

    Hodgson, A.T.; Beal, D.; Chandra, S.

    1998-09-01

    . The house with the modified ventilation system and several lower emitting materials had consistently low TVOC concentrations that were near 1 mg m{sup -3}. There were no large decreases with time in the emission rates of the individual VOCs or TVOC during the course of the study. However, the emission rates were often lowest in the final sampling with the notable exception of the acetic acid emission rate that increased with time. The source of the aldehydes was most likely engineered wood products, such as the plywood floor sheeting and possibly other structural or interior components. The source of the acetic acid was uncertain. The effects of the source substitution treatments were measurable but turned out to be relatively minor due to the predominance of other sources.

  1. Characterization of Inner Tracker silicon prototype sensors using a 106 Ru-source and a 1083 nm laser system

    CERN Document Server

    Bauer, C; Pugatch, V; Schmelling, M; Schwingenheuer, B; Sievers, P

    2001-01-01

    Silicon strip sensors will be used as technology for the LHCb Inner Tracker. The signal-to-noise ratio (S/N) and the charge division among two neighbouring strips are important sensor parameters. In order to investigate the charge sharing between two adjacent strips, measurements with a 1083 nm laser were performed. Minimum ionizing electrons from a ruthenium-source were used to study the S/N-performance of the silicon sensors. The S/N-measurements were also performed with sensors after irradiation with 24 GeV protons up to a fluence of 1.7*10^14 cm^-2, corresponding to more than 10 years of LHCb Inner Tracker operation in the most irradiated zones.

  2. Systematic Characterization of Radiated Energy and Static Stress Drop of Global Subduction Earthquakes from Source Time Functions Analysis

    Science.gov (United States)

    Vallee, M.; Chounet, A.

    2014-12-01

    Source Time Functions (STFs) describe how the seismic moment (Mo) is released with time. In addition to moment magnitude Mw, they carry information on more detailed rupture properties, such as static stress drop Δσ and radiated energy Er. Here we systematically analyze a set of 1500 STFs extracted from the SCARDEC method (Vallée et al 2011), containing the Mw>5.8, shallow (zglobal scale, we confirm the scale-invariance of Δσ with magnitude, while the apparent stress µEr/Mo slightly increases with seismic moment. In a second step, the source parameters distribution is investigated in light of the tectonic context of the earthquakes: we find that subduction interplate earthquakes have lower stress drop and apparent stress relative to all other earthquakes (e.g. crustal earthquakes), in agreement with other approaches (Houston, 2001; Allmann and Shearer, 2009). This observation may reflect the fact that subduction plate boundaries host a very large number of earthquakes, making the fault zone "mature"; or, it may be the consequence of the hydrated subducted materials leading to specific frictional properties. This finding may explain why damages observed after crustal earthquakes tend to be larger than the ones due to subduction earthquakes of the same magnitude. We finally focus on subduction interplate earthquakes (approximately 700 earthquakes) by considering 18 regional segments of subduction zones. We find that these segments do not have the same signature in terms of dynamic rupture properties, which means that large scale plate convergence properties influence rupture behavior. In a given segment, local heterogeneities of stress drop or radiated energy can be associated with local features of the subduction zone: in particular, we find that low coupled zones generate earthquakes with low stress drop and apparent stress.

  3. Characterization of the PTW SourceCheck ionization chamber with the Valencia lodgment for (125)I seed verification.

    Science.gov (United States)

    Tornero-López, Ana M; Torres Del Río, Julia; Ruiz, Carmen; Perez-Calatayud, Jose; Guirado, Damián; Lallena, Antonio M

    2015-12-01

    In brachytherapy using (125)I seed implants, a verification of the air kerma strength of the sources used is required. Typically, between 40 and 100 seeds are implanted. Checking all of them is unaffordable, especially when seeds are disposed in sterile cartridges. Recently, a new procedure allowing the accomplishment of the international recommendations has been proposed for the seedSelectron system of Elekta Brachytherapy. In this procedure, the SourceCheck ionization chamber is used with a special lodgment (Valencia lodgment) that allows to measure up to 10 seeds simultaneously. In this work we analyze this procedure, showing the feasibility of the approximations required for its application, as well as the effect of the additional dependence with the air density that shows the chamber model used. Uncertainty calculations and the verification of the approximation needed to obtain a calibration factor for the Valencia lodgment are carried out. The results of the present work show that the chamber dependence with the air density is the same whether the Valencia lodgment is used or not. On the contrary, the chamber response profile is influenced by the presence of the lodgment. The determination of this profile requires various measurements due to the nonnegligible variability found between different experiments. If it is considered, the uncertainty in the determination of the air-kerma strength increases from 0.5% to 1%. Otherwise, a systematic additional uncertainty of 1% would occur. This could be relevant for the comparison between user and manufacturer measurements that is mandatory in the case studied here.

  4. Characterization of serine hydroxymethyltransferase GlyA as a potential source of D-alanine in Chlamydia pneumoniae

    Directory of Open Access Journals (Sweden)

    Stefania eDe Benedetti

    2014-02-01

    Full Text Available For intracellular Chlamydiaceae, there is no need to withstand osmotic challenges, and a functional cell wall has not been detected in these pathogens so far. Nevertheless, penicillin inhibits cell division in Chlamydiaceae resulting in enlarged aberrant bodies, a phenomenon known as chlamydial anomaly.D-alanine is a unique and essential component in the biosynthesis of bacterial cell walls. In free-living bacteria like Escherichia coli, penicillin-binding proteins such as monofunctional transpeptidases PBP2 and PBP3, the putative targets of penicillin in Chlamydiaceae, cross-link adjacent peptidoglycan strands via meso-diaminopimelic acid and D-Ala-D-Ala moieties of pentapeptide side chains. In the absence of genes coding for alanine racemase Alr and DadX homologs, the source of D-Ala and thus the presence of substrates for PBP2 and PBP3 activity in Chlamydiaceae has puzzled researchers for years. Interestingly, Chlamydiaceae genomes encode GlyA, a serine hydroxymethyltransferase that has been shown to exhibit slow racemization of D- and L- alanine as a side reaction in E. coli. We show that GlyA from Chlamydia pneumoniae can serve as a source of D-Ala. GlyA partially reversed the D-Ala auxotrophic phenotype of an E. coli racemase double mutant. Moreover, purified chlamydial GlyA had racemase activity on L-Ala in vitro and was inhibited by D-cycloserine, identifying GlyA, besides D-Ala ligase MurC/Ddl, as an additional target of this competitive inhibitor in Chlamydiaceae. Proof of D-Ala biosynthesis in Chlamydiaceae helps to clarify the structure of cell wall precursor lipid II and the role of chlamydial penicillin-binding proteins in the development of non-dividing aberrant chlamydial bodies and persistence in the presence of penicillin.

  5. Characterizing and sourcing ambient PM2.5 over key emission regions in China I: Water-soluble ions and carbonaceous fractions

    Science.gov (United States)

    Zhou, Jiabin; Xing, Zhenyu; Deng, Junjun; Du, Ke

    2016-06-01

    During the past decade, huge research resources have been devoted into studies of air pollution in China, which generated abundant datasets on emissions and pollution characterization. Due to the complex nature of air pollution as well as the limitations of each individual investigating approach, the published results were sometimes perplexing and even contradicting. This research adopted a multi-method approach to investigate region-specific air pollution characteristics and sources in China, results obtained using different analytical and receptor modeling methods were inter-compared for validation and interpretation. A year-round campaign was completed for comprehensive characterization of PM2.5 over four key emission regions: Beijing-Tianjin-Hebei (BTH), Yangzi River Delta (YRD), Pearl River Delta (PRD), and Sichuan Basin (SB). Atmospheric PM2.5 samples were collected from 10/2012 to 08/2013 at four regional sites, located on the diffusion paths of air masses from their corresponding megacities (i.e., Beijing, Shanghai, Guangzhou, and Chengdu). The annual average PM2.5 mass concentrations showed distinct regional difference, with the highest observed at BTH and lowest at PRD site. Nine water-soluble ions together contributed 33-41% of PM2.5 mass, with three dominant ionic species being SO42-, NO3-, NH4+, and carbonaceous particulate matter contributed 16-23% of PM2.5 mass. This implied that combustion and secondary formation were the main sources for PM2.5 in China. In addition, SO42-, NO3-, NH4+, and carbonaceous components (OC, EC) showed clear seasonal patterns with the highest concentration occurring in winter while the lowest in summer. Principal component analysis performed on aerosol data revealed that vehicular emissions, coal/biomass combustion, industry source, soil dust as well as secondary formation were the main potential sources for the ionic components of PM2.5. The characteristic chemical species combined with back trajectory analysis indicated

  6. Characterization and source term assessments of radioactive particles from Marshall Islands using non-destructive analytical techniques

    Energy Technology Data Exchange (ETDEWEB)

    Jernstroem, J. [Laboratory of Radiochemistry, Department of Chemistry, P.O. Box 55, FI-00014 University of Helsinki (Finland)]. E-mail: jussi.jernstrom@helsinki.fi; Eriksson, M. [IAEA-MEL, International Atomic Energy Agency - Marine Environment Laboratory, 4 Quai Antoine 1er, MC 98000 Monaco (Monaco); Simon, R. [Institute for Synchrotron Radiation, Forschungszentrum Karlsruhe GmbH, D-76021 Karlsruhe (Germany); Tamborini, G. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe (Germany); Bildstein, O. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe (Germany); Marquez, R. Carlos [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe (Germany); Kehl, S.R. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551-0808 (United States); Hamilton, T.F. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551-0808 (United States); Ranebo, Y. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe (Germany); Betti, M. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe (Germany)]. E-mail: maria.betti@ec.europa.eu

    2006-08-15

    Six plutonium-containing particles stemming from Runit Island soil (Marshall Islands) were characterized by non-destructive analytical and microanalytical methods. Composition and elemental distribution in the particles were studied with synchrotron radiation based micro X-ray fluorescence spectrometry. Scanning electron microscope equipped with energy dispersive X-ray detector and with wavelength dispersive system as well as a secondary ion mass spectrometer were used to examine particle surfaces. Based on the elemental composition the particles were divided into two groups: particles with pure Pu matrix, and particles where the plutonium is included in Si/O-rich matrix being more heterogenously distributed. All of the particles were identified as nuclear fuel fragments of exploded weapon components. As containing plutonium with low {sup 240}Pu/{sup 239}Pu atomic ratio, less than 0.065, which corresponds to weapons-grade plutonium or a detonation with low fission yield, the particles were identified to originate from the safety test and low-yield tests conducted in the history of Runit Island. The Si/O-rich particles contained traces of {sup 137}Cs ({sup 239+240}Pu/{sup 137}Cs activity ratio higher than 2500), which indicated that a minor fission process occurred during the explosion. The average {sup 241}Am/{sup 239}Pu atomic ratio in the six particles was 3.7 x 10{sup -3} {+-} 0.2 x 10{sup -3} (February 2006), which indicated that plutonium in the different particles had similar age.

  7. Characterization and source term assessments of radioactive particles from Marshall Islands using non-destructive analytical techniques

    Science.gov (United States)

    Jernström, J.; Eriksson, M.; Simon, R.; Tamborini, G.; Bildstein, O.; Marquez, R. Carlos; Kehl, S. R.; Hamilton, T. F.; Ranebo, Y.; Betti, M.

    2006-08-01

    Six plutonium-containing particles stemming from Runit Island soil (Marshall Islands) were characterized by non-destructive analytical and microanalytical methods. Composition and elemental distribution in the particles were studied with synchrotron radiation based micro X-ray fluorescence spectrometry. Scanning electron microscope equipped with energy dispersive X-ray detector and with wavelength dispersive system as well as a secondary ion mass spectrometer were used to examine particle surfaces. Based on the elemental composition the particles were divided into two groups: particles with pure Pu matrix, and particles where the plutonium is included in Si/O-rich matrix being more heterogenously distributed. All of the particles were identified as nuclear fuel fragments of exploded weapon components. As containing plutonium with low 240Pu/ 239Pu atomic ratio, less than 0.065, which corresponds to weapons-grade plutonium or a detonation with low fission yield, the particles were identified to originate from the safety test and low-yield tests conducted in the history of Runit Island. The Si/O-rich particles contained traces of 137Cs ( 239 + 240 Pu/ 137Cs activity ratio higher than 2500), which indicated that a minor fission process occurred during the explosion. The average 241Am/ 239Pu atomic ratio in the six particles was 3.7 × 10 - 3 ± 0.2 × 10 - 3 (February 2006), which indicated that plutonium in the different particles had similar age.

  8. Analytical characterization of mannosylerythritol lipid biosurfactants produced by biosynthesis based on feedstock sources from the agrofood industry.

    Science.gov (United States)

    Onghena, Matthias; Geens, Tinne; Goossens, Eliane; Wijnants, Marc; Pico, Yolanda; Neels, Hugo; Covaci, Adrian; Lemiere, Filip

    2011-05-01

    Mannosylerythritol lipids (MELs) are currently one of the most promising biosurfactants because of their multifunctional applications and good biodegradability. Depending on the yeast strain and the feedstock used for the fermentation process, structural variations in the MELs obtained occur. Therefore, MELs produced by Pseudozyma aphidis DSMZ 70725 with a soybean oil feedstock were characterized by chromatography and mass spectrometry (MS). Column chromatography with silica provided fractionation of the different types of MEL. High-performance liquid chromatography combined with MS was employed for the analysis of the MEL fractions and crude mixtures. A characteristic MS pattern for the MELs was obtained and indications of the presence of new MEL homologues, showing the incorporation of longer and more unsaturated fatty acid chains than previously reported, were given. Gas chromatography-MS analysis confirmed the presence of such unsaturated fatty acid chains in the MELs, demonstrating the incorporation of fatty acids with lengths ranging from C(8) to C(14) and with up to two unsaturations per chain. The incorporation of C(16) and C(18) fatty acid chains requires further investigation. MS/MS data allowed the unambiguous identification of the fatty acids present in the MELs. The product ion spectra also revealed the presence of a new isomeric class of MELs, bearing an acetyl group on the erythritol moiety. PMID:21318245

  9. Single-Volume Neutron Scatter Camera for High-Efficiency Neutron Imaging and Source Characterization. Year 2 of 3 Summary

    Energy Technology Data Exchange (ETDEWEB)

    Brubaker, Erik [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2015-10-01

    The neutron scatter camera (NSC), an imaging spectrometer for fission energy neutrons, is an established and proven detector for nuclear security applications such as weak source detection of special nuclear material (SNM), arms control treaty verification, and emergency response. Relative to competing technologies such as coded aperture imaging, time-encoded imaging, neutron time projection chamber, and various thermal neutron imagers, the NSC provides excellent event-by-event directional information for signal/background discrimination, reasonable imaging resolution, and good energy resolution. Its primary drawback is very low detection efficiency due to the requirement for neutron elastic scatters in two detector cells. We will develop a singlevolume double-scatter neutron imager, in which both neutron scatters can occur in the same large active volume. If successful, the efficiency will be dramatically increased over the current NSC cell-based geometry. If the detection efficiency approaches that of e.g. coded aperture imaging, the other inherent advantages of double-scatter imaging would make it the most attractive fast neutron detector for a wide range of security applications.

  10. Source term identification of environmental radioactive Pu/U particles by their characterization with non-destructive spectrochemical analytical techniques

    Science.gov (United States)

    Eriksson, M.; Osán, J.; Jernström, J.; Wegrzynek, D.; Simon, R.; Chinea-Cano, E.; Markowicz, A.; Bamford, S.; Tamborini, G.; Török, S.; Falkenberg, G.; Alsecz, A.; Dahlgaard, H.; Wobrauschek, P.; Streli, C.; Zoeger, N.; Betti, M.

    2005-04-01

    Six radioactive particles stemming from Thule area (NW-Greenland) were investigated by gamma-ray and L X-ray spectrometry based on radioactive disintegration, scanning electron microscopy coupled with energy-dispersive and wavelength-dispersive X-ray spectrometer, synchrotron radiation based techniques as microscopic X-ray fluorescence, microscopic X-ray absorption near-edge structure (μ-XANES) as well as combined X-ray absorption and fluorescence microtomography. Additionally, one particle from Mururoa atoll was examined by microtomography. From the results obtained, it was found out that the U and Pu were mixed in the particles. The U/Pu intensity ratios in the Thule particles varied between 0.05 and 0.36. The results from the microtomography showed that U/Pu ratio was not homogeneously distributed. The 241Am/ 238 + 239 + 240 Pu activity ratios varied between 0.13 and 0.17, indicating that the particles originate from different source terms. The oxidation states of U and Pu as determined by μ-XANES showed that U(IV) is the preponderant species and for Pu, two types of particles could be evidenced. One set had about 90% Pu(IV) while in the other the ratio Pu(IV)/Pu(VI) was about one third.

  11. Synthetic data products for future H I galaxy surveys: a tool for characterizing source confusion in spectral line stacking experiments

    Science.gov (United States)

    Elson, E. C.; Blyth, S. L.; Baker, A. J.

    2016-08-01

    Much of our current understanding of neutral, atomic gas in galaxies comes from radio observations of the nearby Universe. Until the next generation of instruments allow us to push to much higher redshifts, we must rely mostly upon theoretical models of galaxy formation to provide us with key insights into the likely cosmic evolution of H I in the Universe, and its links to molecular clouds and star formation. In this work, we present a new set of methods to convert mock galaxy catalogues into synthetic data cubes containing model galaxies with realistic spatial and spectral H I distributions over large cosmological volumes. Such synthetic data products can be used to guide observing and data handling/analysis strategies for forthcoming H I galaxy surveys. As a demonstration of the potential use of our simulated products we use them to conduct several mock H I stacking experiments for both low and high-redshift galaxy samples. The stacked spectra can be accurately decomposed into contributions from target and non-target galaxies, revealing in all co-added spectra large fractions of contaminant mass due to source confusion. Our results are consistent with similar estimates extrapolated from z = 0 observational data. The amount of confused mass in a stacked spectrum grows almost linearly with the size of the observational beam, suggesting potential overestimates of Ω _{H I} by some recent H I stacking experiments. Our simulations will allow the study of subtle redshift-dependent effects in future stacking analyses.

  12. Isolation and characterization of a Sinorhizobium fredii mutant that cannot utilize proline as the sole carbon and nitrogen source

    Institute of Scientific and Technical Information of China (English)

    HUANG Sheng; BAI Xueliang; MA Qingsheng; TANG Xianlai; WU Bo

    2004-01-01

    Sinorhizobium fredii strain HN01 can use proline as the sole carbon and nitrogen source. A mutant strain GXHN100 unable to catabolize proline was screened from 6000 Tn5gusA5 random insertional mutants of S.fredii strain HN01. Sequencing analysis showed that an open reading frame, named pmrA (proline metabolic relative), was inserted by the Tn5gusA5. A positive clone, named pGXHN100 which containing 3.3kb foreign DNA fragment of S.fredii strain HN01, was isolated from a partial gene library of S.fredii HN01 by colony in situ hybridization. Sequence analysis showed that pGXHN100 contained the entire pmrA gene. The 3.3kb DNA fragment of pGXHN100 was cloned into a broad-host-range cosmid vector pLAFR3 to form plasmid pGXHN200 which was subsequently introduced into GXHN100 to form a complemented strain GXHN200. Plant test showed that GXHN100 was effective and no obvious changes in nitrogenase activity comparing with parental strain. But GXHN100 nodulated 2 days later on soybean and its nodulation efficiency and competitiveness were decreased. The complemented strain GXHN200 restored the nodulation efficiency and competitiveness of GXHN100 to the wild type.

  13. Isolation and molecular characterization of Acanthamoeba genotypes in recreational and domestic water sources from Jamaica, West Indies.

    Science.gov (United States)

    Todd, Cheridah D; Reyes-Batlle, María; Piñero, José E; Martínez-Carretero, Enrique; Valladares, Basilio; Streete, Don; Lorenzo-Morales, Jacob; Lindo, John F

    2015-09-01

    Free living amoebae (FLA) are amphizoic protozoa that are ubiquitous in nature. Infection with FLA may result in neurological, ocular and skin infections. Exposure to Acanthamoeba occurs frequently through water contact and knowledge of the presence of the organisms in water sources is important in understanding transmission dynamics. The distribution of Acanthamoeba was studied in recreational and domestic water samples collected from across Jamaica. Morphological assessment and polymerase chain reaction revealed Acanthamoeba spp. isolates in 50.6% (42/83) and 17.3% (14/81) of recreational and domestic water, respectively. Sequencing of the DF3 region of the 18S rDNA resulted in the identification of genotypes T3, T4, T5, T10 and T11 corresponding to Acanthamoeba spp: A. griffini, A. triangularis, A. lenticulata, A. culbertsoni and A. hatchetti. Moreover, T4 was the most frequently isolated genotype in both recreational and domestic water. Thermotolerance and osmotolerance assays indicated that most isolates were potentially pathogenic. This is the first report of T3 and T10 genotypes in the Caribbean and the first report of these Acanthamoeba spp. in Jamaican waters. The study shows that there is potential risk of infection to contact wearers who practise poor lens care. Further, Acanthamoeba should be considered as a cause of neurological infections in Jamaica.

  14. Completing The Characterization Of Stellar Populations In The Galaxy: Final Catalogs Of Unique Galex Uv Sources And Of Milky Way Hot Stars.

    Science.gov (United States)

    Bianchi, Luciana

    The Galaxy Evolution Explorer (GALEX) has performed the first extensive surveys in the Ultraviolet (UV), filling the last gap in our view of the sky across the electromagnetic spectrum. Its legacy is an unprecedented database with more than 200 million source measurements in far-UV and near-UV. The UV surveys offer unique sensitivity for identifying and studying selected classes of astrophysical objects, both stellar and extra- galactic, notably hot stars, star-forming galaxies, and QSOs (redshift ≤sssim2.4). In order to examine the overall content and distribution of UV sources over the sky, and to classify them by astrophysical class, we propose to construct final catalogs of UV unique sources with homogeneous quality (eliminating duplicate measurements of the same source, excluding artifacts, adding science flags, etc). Such catalogs will facilitate a variety of science investigations on UV-selected samples by the community, in addition to our own science goal, as well as planning of observations with future instruments. We will build the catalogs (high-level science product) using recipes developed for our early version (Bianchi et al. 2011a) but with expanded tools, science flags, and corollary data, in addition to the much larger area coverage with respect to our early version. To facilitate UV source classification and characterization, we will also match the catalogs of unique UV sources with existing ground-based surveys, adding optical and infrared magnitudes to the two UV GALEX magnitudes, and construct flags to identify sources with multiple matches. These products will allow us (and the community) to extract UV-selected samples for several projects. We will use our catalogs for our own science goal: an unbiased census of Milky Way hot white dwarfs (WD). Hot WDs are elusive at all wavelengths except the UV, given their very high temperatures to which optical colors are insensitive, and low optical luminosity. From our proposed UV catalogs we will be

  15. DEVELOPING AND EXPLOITING A UNIQUE SEISMIC DATA SET FROM SOUTH AFRICAN GOLD MINES FOR SOURCE CHARACTERIZATION AND WAVE PROPAGATION

    Energy Technology Data Exchange (ETDEWEB)

    Julia, J; Nyblade, A A; Gok, R; Walter, W R; Linzer, L; Durrheim, R

    2008-07-08

    locations may move a few hundreds of meters. The full moment tensor determination has revealed that the most common focal mechanism (47 out of 82 solutions for events in the 0.2 < ML < 4.1 range) consists of a similar percentage of isotropic (implosive) and deviatoric components, with a normal fault-type best double couple. We have also calibrated the regional stations for seismic coda derived source spectra and moment magnitude using the envelope methodology of Mayeda et al (2003). We tie the coda Mw to independent values from waveform modeling. The resulting coda-based source spectra of shallow mining-related events show significant spectral peaking that is not seen in deeper tectonic earthquakes. This coda peaking may be an independent method of identifying shallow events and is similar to coda peaking previously observed for Nevada explosions, where the frequency of the observed spectral peak correlates with depth of burial (Murphy et al., 2008).

  16. DEVELOPING AND EXPLOITING A UNIQUE DATASET FROM SOUTH AFRICAN GOLD MINES FOR SOURCE CHARACTERIZATION AND WAVE PROPAGATION

    Energy Technology Data Exchange (ETDEWEB)

    Julia, J; Nyblade, A; Gok, R; Walter, W; Linzer, L; Durrheim, R

    2009-07-06

    , corrected by correlating waveforms obtained from theoretical and empirical rotation angles. Full moment tensor solutions have been obtained for selected events within the Savuka network volume, with moment magnitudes in the 0.5 < M{sub W} < 2.6 range. The solutions were obtained by inverting P-, SV-, and SH-spectral amplitudes measured on the theoretically rotated waveforms with visually assigned polarities. Most of the solutions have a non-zero implosive contribution (47 out of 76), while a small percentage is purely deviatoric (10 out of 76). The deviatoric moment tensors range from pure double couple to pure non-double couple mechanisms. We have also calibrated the regional stations for seismic coda-derived source spectra and moment magnitude using the envelope methodology of Mayeda et al. (2003). they tie the coda M{sub w} to independent values from waveform modeling. The resulting coda-based source spectra of shallow mining-related events show significant spectral peaking that is not seen in deeper tectonic earthquakes. This coda peaking may be an independent method of identifying shallow events and is similar to coda peaking with previously observed for Nevada explosions, where the frequency of the observed spectral peak correlates with the depth of burial (Murphy et al., 2009).

  17. Measurements of volatile organic compounds in rural area of Yangtze River Delta region: Measurement comparison and source characterization

    Science.gov (United States)

    Kudo, S.; Saito, S.; Tanimoto, H.; Inomata, S.; Kanaya, Y.; Yamaji, K.; Xiaole, P.; Wang, Z.

    2012-12-01

    Concentrations of non-methane volatile organic compounds (NMVOCs) in ambient air were measured by three different methods in a city of Rudong in May and June 2010. Intercomparison of VOCs measurements was made among in-situ measurements and canister analyses with a gas chromatography/flame ionization detection/mass spectrometry (GC/FID/MS) and proton transfer reaction-mass spectrometry (PTR-MS). For 18 VOCs measured by GC/FID/MS, canister analyses and in-situ measurements were in reasonably good agreement (R2 > 0.90). However, alkenes and aromatics in canister samples were found to be lower than in-situ measurements likely due to adsorption of low volatile compounds onto the wall surface inside canisters. For comparison of GC/MS with PTR-MS, the correlations for isoprene, benzene, C8 aromatics, and C9 aromatics were highly significant (R2 ≥ 0.93) with each other. However, there were quantitative differences between GC/MS and PTR-MS. For example, isoprene measured by PTR-MS indicates existence of interferences from C5 alcohols, C5 aldehydes, and furan. During the latter part of the field campaign, elevated concentrations of VOCs and CO were observed when intensive burning of crop residues took place near the sampling site. The concentrations of ethane, propane, ethane, isoprene, acetone, acetaldehyde, and aromatics varied in the range between 0 and 30 ppbv. The observed VOCs concentrations are compared to model results by a regional chemistry-transport model for Asia. The modeled concentrations underestimated the observed concentrations by a factor of 10 for NMHCs, 100 for aromatics, 10 for oxygenated VOCs, implying that current emissions inventories miss a number of sources for these VOCs.

  18. Establishment and characterization of a Satureja khuzistanica Jamzad (Lamiaceae) cell suspension culture: a new in vitro source of rosmarinic acid.

    Science.gov (United States)

    Sahraroo, Amir; Mirjalili, Mohammad Hossein; Corchete, Purificación; Babalar, Mesbah; Fattahi Moghadam, Mohammad Reza

    2016-08-01

    An in vitro approach to the production of rosmarinic acid (RA), a medicinally important caffeic acid ester, in a cell suspension culture (CSC) of Satureja khuzistanica Jamzad (Lamiaceae) has been investigated for the first time. The CSC was established from friable calli derived from shoot tip explants in Gamborg's B5 liquid medium supplemented with 30 g/L sucrose, 20 mg/L L-glutamine, 200 mg/L casein hydrolysate, 5 mg/L benzyladenine (BA) and 1 mg/L indole-3-butyric acid (IBA). The effect of nitrogen source (KNO3 and (NH4)2SO4) and their different concentrations on the fresh and dry weight (g/L), as well as RA content (mg/g dry weight) were measured. CSC growth measurements indicated a maximum specific cell growth rate of 1.5/day, a doubling time of 7.6 days and a high percentage of cell viability (96.4 %) throughout the growth cycle. Maximum cell fresh weight (353.5 g/L), dry weight (19.7 g/L) and RA production (180.0 mg/g) were attained at day 21 of culture. Cell growth and RA content were affected by nitrogen deficiency. Media containing 8.3 mM of total nitrogen (¼ of B5 standard medium) led to a minimum cell fresh weight (243.0 g/L), dry weight (17.4 g/L) and RA content (38.0 mg/g) after 21 days. The established CSC provided useful material for further optimization experiments aimed at a large-scale production of RA. PMID:26264595

  19. Use of Advanced Tsunami Hazard Assessment Techniques and Tsunami Source Characterizations in U.S. and International Nuclear Regulatory Activities

    Science.gov (United States)

    Kammerer, A. M.; Godoy, A. R.

    2009-12-01

    In response to the 2004 Indian Ocean Tsunami, as well as the anticipation of the submission of license applications for new nuclear facilities, the United States Nuclear Regulatory Commission (US NRC) initiated a long-term research program to improve understanding of tsunami hazard levels for nuclear power plants and other coastal facilities in the United States. To undertake this effort, the US NRC organized a collaborative research program jointly undertaken with researchers at the United States Geological Survey (USGS) and the National Oceanic and Atmospheric Administration (NOAA) for the purpose of assessing tsunami hazard on the Atlantic and Gulf Coasts of the United States. This study identified and modeled both seismic and landslide tsunamigenic sources in the near- and far-field. The results from this work are now being used directly as the basis for the review of tsunami hazard at potential nuclear plant sites. This application once again shows the importance that the earth sciences can play in addressing issues of importance to society. Because the Indian Ocean Tsunami was a global event, a number of cooperative international activities have also been initiated within the nuclear community. The results of US efforts are being incorporated into updated regulatory guidance for both the U.S. Nuclear Regulatory Commission and the United Nation’s International Atomic Energy Agency (IAEA). Coordinated efforts are underway to integrate state-of-the art tsunami warning tools developed by NOAA into NRC and IAEA activities. The goal of the warning systems project is to develop automated protocols that allow scientists at these agencies to have up-to-the minute user-specific information in hand shortly after a potential tsunami has been identified by the US Tsunami Warning System. Lastly, USGS and NOAA scientists are assisting the NRC and IAEA in a special Extra-Budgetary Program (IAEA EBP) on tsunami being coordinated by the IAEA’s International Seismic Safety

  20. Source Characterization and Temporal Variation of Methane Seepage from Thermokarst Lakes on the Alaska North Slope in Response to Arctic Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-09-30

    The goals of this research were to characterize the source, magnitude and temporal variability of methane seepage from thermokarst lakes (TKL) within the Alaska North Slope gas hydrate province, assess the vulnerability of these areas to ongoing and future arctic climate change and determine if gas hydrate dissociation resulting from permafrost melting is contributing to the current lake emissions. Analyses were focused on four main lake locations referred to in this report: Lake Qalluuraq (referred to as Lake Q) and Lake Teshekpuk (both on Alaska�s North Slope) and Lake Killarney and Goldstream Bill Lake (both in Alaska�s interior). From analyses of gases coming from lakes in Alaska, we showed that ecological seeps are common in Alaska and they account for a larger source of atmospheric methane today than geologic subcap seeps. Emissions from the geologic source could increase with potential implications for climate warming feedbacks. Our analyses of TKL sites showing gas ebullition were complemented with geophysical surveys, providing important insight about the distribution of shallow gas in the sediments and the lake bottom manifestation of seepage (e.g., pockmarks). In Lake Q, Chirp data were limited in their capacity to image deeper sediments and did not capture the thaw bulb. The failure to capture the thaw bulb at Lake Q may in part be related to the fact that the present day lake is a remnant of an older, larger, and now-partially drained lake. These suggestions are consistent with our analyses of a dated core of sediment from the lake that shows that a wetland has been present at the site of Lake Q since approximately 12,000 thousand years ago. Chemical analyses of the core indicate that the availability of methane at the site has changed during the past and is correlated with past environmental changes (i.e. temperature and hydrology) in the Arctic. Discovery of methane seeps in Lake Teshekpuk in the northernmost part of the lake during 2009

  1. Source Characterization and Temporal Variation of Methane Seepage from Thermokarst Lakes on the Alaska North Slope in Response to Arctic Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2012-09-30

    The goals of this research were to characterize the source, magnitude and temporal variability of methane seepage from thermokarst lakes (TKL) within the Alaska North Slope gas hydrate province, assess the vulnerability of these areas to ongoing and future arctic climate change and determine if gas hydrate dissociation resulting from permafrost melting is contributing to the current lake emissions. Analyses were focused on four main lake locations referred to in this report: Lake Qalluuraq (referred to as Lake Q) and Lake Teshekpuk (both on Alaska's North Slope) and Lake Killarney and Goldstream Bill Lake (both in Alaska's interior). From analyses of gases coming from lakes in Alaska, we showed that ecological seeps are common in Alaska and they account for a larger source of atmospheric methane today than geologic subcap seeps. Emissions from the geologic source could increase with potential implications for climate warming feedbacks. Our analyses of TKL sites showing gas ebullition were complemented with geophysical surveys, providing important insight about the distribution of shallow gas in the sediments and the lake bottom manifestation of seepage (e.g., pockmarks). In Lake Q, Chirp data were limited in their capacity to image deeper sediments and did not capture the thaw bulb. The failure to capture the thaw bulb at Lake Q may in part be related to the fact that the present day lake is a remnant of an older, larger, and now-partially drained lake. These suggestions are consistent with our analyses of a dated core of sediment from the lake that shows that a wetland has been present at the site of Lake Q since approximately 12,000 thousand years ago. Chemical analyses of the core indicate that the availability of methane at the site has changed during the past and is correlated with past environmental changes (i.e. temperature and hydrology) in the Arctic. Discovery of methane seeps in Lake Teshekpuk in the northernmost part of the lake during 2009

  2. Molecular characterization of bacterial diversity in Lodgepole pine (Pinus contorta) rhizosphere soils from British Columbia forest soils differing in disturbance and geographic source.

    Science.gov (United States)

    Chow, Monica L; Radomski, Christopher C; McDermott, Joseph M; Davies, Julian; Axelrood, Paige E

    2002-12-01

    Rhizosphere bacteria from Lodgepole pine (Pinus contorta) seedlings were characterized from forest soils which differed in disturbance and geographic source. Soil disturbance treatments included whole-tree harvesting with and without heavy soil compaction and whole-tree harvesting with complete surface organic matter removal and heavy soil compaction from British Columbia (BC) Ministry of Forests Long-Term Soil Productivity installations in three biogeoclimatic subzones in central BC, Canada. Bacterial community members were characterized by DNA sequence analysis of 16S rRNA gene fragments following direct DNA isolation from soil, polymerase chain reaction amplification and cloning. Phylogenetic analyses revealed that 85% of 709 16S rDNA clones were classified as alpha-, beta-, gamma-, and delta-Proteobacteria, Actinobacteria, Cytophaga-Flexibacter-Bacteroides group, Acidobacterium, Verrucomicrobia, and candidate divisions OP10 and TM6. Members of the Proteobacteria and Acidobacterium represented 55% and 19% of the clone library, respectively, whereas the remaining bacterial divisions each comprised less than 4% of the clone library. One hundred and six 16S rDNA clones could not be classified into known bacterial divisions. No significant differences were detected for soil disturbance treatment or site effects on the proportions of 16S rDNA clones affiliated with Proteobacteria and Acidobacterium. Phylogenetic analyses revealed that it was common for 16S rRNA gene fragments from different soil disturbance treatments and geographic locations to be closely related. PMID:19709294

  3. Experimental Component Characterization, Monte-Carlo-Based Image Generation and Source Reconstruction for the Neutron Imaging System of the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Barrera, C A; Moran, M J

    2007-08-21

    The Neutron Imaging System (NIS) is one of seven ignition target diagnostics under development for the National Ignition Facility. The NIS is required to record hot-spot (13-15 MeV) and downscattered (6-10 MeV) images with a resolution of 10 microns and a signal-to-noise ratio (SNR) of 10 at the 20% contour. The NIS is a valuable diagnostic since the downscattered neutrons reveal the spatial distribution of the cold fuel during an ignition attempt, providing important information in the case of a failed implosion. The present study explores the parameter space of several line-of-sight (LOS) configurations that could serve as the basis for the final design. Six commercially available organic scintillators were experimentally characterized for their light emission decay profile and neutron sensitivity. The samples showed a long lived decay component that makes direct recording of a downscattered image impossible. The two best candidates for the NIS detector material are: EJ232 (BC422) plastic fibers or capillaries filled with EJ399B. A Monte Carlo-based end-to-end model of the NIS was developed to study the imaging capabilities of several LOS configurations and verify that the recovered sources meet the design requirements. The model includes accurate neutron source distributions, aperture geometries (square pinhole, triangular wedge, mini-penumbral, annular and penumbral), their point spread functions, and a pixelated scintillator detector. The modeling results show that a useful downscattered image can be obtained by recording the primary peak and the downscattered images, and then subtracting a decayed version of the former from the latter. The difference images need to be deconvolved in order to obtain accurate source distributions. The images are processed using a frequency-space modified-regularization algorithm and low-pass filtering. The resolution and SNR of these sources are quantified by using two surrogate sources. The simulations show that all LOS

  4. sRecovery Act: Geologic Characterization of the South Georgia Rift Basin for Source Proximal CO2 Storage

    Energy Technology Data Exchange (ETDEWEB)

    Waddell, Michael

    2014-09-30

    This study focuses on evaluating the feasibility and suitability of using the Jurassic/Triassic (J/TR) sediments of the South Georgia Rift basin (SGR) for CO2 storage in southern South Carolina and southern Georgia The SGR basin in South Carolina (SC), prior to this project, was one of the least understood rift basin along the east coast of the U.S. In the SC part of the basin there was only one well (Norris Lightsey #1) the penetrated into J/TR. Because of the scarcity of data, a scaled approach used to evaluate the feasibility of storing CO2 in the SGR basin. In the SGR basin, 240 km (~149 mi) of 2-D seismic and 2.6 km2 3-D (1 mi2) seismic data was collected, process, and interpreted in SC. In southern Georgia 81.3 km (~50.5 mi) consisting of two 2-D seismic lines were acquired, process, and interpreted. Seismic analysis revealed that the SGR basin in SC has had a very complex structural history resulting the J/TR section being highly faulted. The seismic data is southern Georgia suggest SGR basin has not gone through a complex structural history as the study area in SC. The project drilled one characterization borehole (Rizer # 1) in SC. The Rizer #1 was drilled but due to geologic problems, the project team was only able to drill to 1890 meters (6200 feet) instead of the proposed final depth 2744 meters (9002 feet). The drilling goals outlined in the original scope of work were not met. The project was only able to obtain 18 meters (59 feet) of conventional core and 106 rotary sidewall cores. All the conventional core and sidewall cores were in sandstone. We were unable to core any potential igneous caprock. Petrographic analysis of the conventional core and sidewall cores determined that the average porosity of the sedimentary material was 3.4% and the average permeability was 0.065 millidarcy. Compaction and diagenetic studies of the samples determined there would not be any porosity or permeability at depth in SC. In Georgia there appears to be porosity in

  5. Simultaneous monitoring and compositions analysis of PM1 and PM2.5 in Shanghai: Implications for characterization of haze pollution and source apportionment.

    Science.gov (United States)

    Qiao, Ting; Zhao, Mengfei; Xiu, Guangli; Yu, Jianzhen

    2016-07-01

    A year-long simultaneous observation of PM1 and PM2.5 were conducted at ECUST campus in Shanghai, the compositions were analyzed and compared. Results showed that PM2.5 was dominated by PM1 on clear days while the contribution of PM1-2.5 to PM2.5 increased on haze days, indicating that PM2.5 should be given priority to characterize or predict haze pollution. On haze days, accumulation of organic carbon (OC), elemental carbon (EC) and primary organic carbon (POC) in PM1-2.5 was faster than that in PM1. Humic-like substances carbon (Hulis-C) in both PM2.5 and PM1 formed faster than water soluble organic carbon (WSOC) on haze days, hence Hulis-C/WSOC increased with the intensification of haze pollution. In terms of water soluble ions, NO3(-)/SO4(2-) in PM1 increased with the aggravation of haze pollution, implying that mobile sources dominated on haze days, so is nitrogen oxidation ratio (NOR). Liquid water content (LWC) in both PM1 and PM2.5 had positive correlations with relative humidity (RH) but negative correlations with visibility, implying that hygroscopic growth might be a factor for visibility impairment, especially LWC in PM1. By comparison with multi-linear equations of LWC in PM1 and PM2.5, NO3(-) exerted a higher influence on hygroscopicity of PM1 than PM2.5, while RH, WSOC, SO4(2-) and NH4(+) had higher effects on PM2.5, especially WSOC. Source apportionment of PM2.5 was also investigated to provide reference for policy making. Cluster analysis by HYSPLIT (HYbrid Single Particle Lagrangian Integrated Trajectory) model showed that PM2.5 originated from marine aerosols, middle-scale transportation and large-scale transportation. Furthermore, PM2.5 on haze days was dominated by middle-scale transportation. In line with source apportionment by positive matrix factorization (PMF) model, PM2.5 was attributed to secondary inorganics, aged sea salt, combustion emissions, hygroscopic growth and secondary organics. Secondary formation was the principle source of

  6. Simultaneous monitoring and compositions analysis of PM1 and PM2.5 in Shanghai: Implications for characterization of haze pollution and source apportionment.

    Science.gov (United States)

    Qiao, Ting; Zhao, Mengfei; Xiu, Guangli; Yu, Jianzhen

    2016-07-01

    A year-long simultaneous observation of PM1 and PM2.5 were conducted at ECUST campus in Shanghai, the compositions were analyzed and compared. Results showed that PM2.5 was dominated by PM1 on clear days while the contribution of PM1-2.5 to PM2.5 increased on haze days, indicating that PM2.5 should be given priority to characterize or predict haze pollution. On haze days, accumulation of organic carbon (OC), elemental carbon (EC) and primary organic carbon (POC) in PM1-2.5 was faster than that in PM1. Humic-like substances carbon (Hulis-C) in both PM2.5 and PM1 formed faster than water soluble organic carbon (WSOC) on haze days, hence Hulis-C/WSOC increased with the intensification of haze pollution. In terms of water soluble ions, NO3(-)/SO4(2-) in PM1 increased with the aggravation of haze pollution, implying that mobile sources dominated on haze days, so is nitrogen oxidation ratio (NOR). Liquid water content (LWC) in both PM1 and PM2.5 had positive correlations with relative humidity (RH) but negative correlations with visibility, implying that hygroscopic growth might be a factor for visibility impairment, especially LWC in PM1. By comparison with multi-linear equations of LWC in PM1 and PM2.5, NO3(-) exerted a higher influence on hygroscopicity of PM1 than PM2.5, while RH, WSOC, SO4(2-) and NH4(+) had higher effects on PM2.5, especially WSOC. Source apportionment of PM2.5 was also investigated to provide reference for policy making. Cluster analysis by HYSPLIT (HYbrid Single Particle Lagrangian Integrated Trajectory) model showed that PM2.5 originated from marine aerosols, middle-scale transportation and large-scale transportation. Furthermore, PM2.5 on haze days was dominated by middle-scale transportation. In line with source apportionment by positive matrix factorization (PMF) model, PM2.5 was attributed to secondary inorganics, aged sea salt, combustion emissions, hygroscopic growth and secondary organics. Secondary formation was the principle source of

  7. SOURCE CHARACTERIZATION OF AIR FRESHENERS

    Science.gov (United States)

    The paper discusses research in which five air fresheners of two styles were analyzed for their constituent volatile organic compounds. Both styles were refills to be inserted into heated electric plug-in units; one refill released the fragrance from a gel pack insert and the oth...

  8. Synthesis and characterization of ZSM-12 type zeolytic catalysts by using different aluminium sources in the petroleum industry; Sintese e caracterizacao de catalisadores zeoliticos do tipo ZSM-12 utilizando diferentes fontes de aluminio na industria do petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Moraes, Marilia R.F.S.; Jesus, Daniela B.; Souza, Marcelo J.B. [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Dept. de Engenharia Quimica; Santos, Consuelo D.; Machado, Sanny W.M.; Pedrosa, Anne M. Garrido [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Dept. de Quimica

    2010-12-15

    The main objective was to synthesize and characterize ZSM-12 zeolites from different sources of aluminium, using hydrothermal method and characterize the catalysts synthesized by X-ray diffractions, thermal analysis and infrared absorption spectroscopy. The X-ray diffractogram showed the formation of zeolites of the family pantasil crystalline. Thermogravimetric curves and FTIR spectra were utilized by monitoring the removal of template and by monitoring the maintenance of zeolite structure. (author)

  9. Seasonal characterization of submicron aerosol chemical composition and organic aerosol sources in the southeastern United States: Atlanta, Georgia,and Look Rock, Tennessee

    Science.gov (United States)

    Hapsari Budisulistiorini, Sri; Baumann, Karsten; Edgerton, Eric S.; Bairai, Solomon T.; Mueller, Stephen; Shaw, Stephanie L.; Knipping, Eladio M.; Gold, Avram; Surratt, Jason D.

    2016-04-01

    A year-long near-real-time characterization of non-refractory submicron aerosol (NR-PM1) was conducted at an urban (Atlanta, Georgia, in 2012) and rural (Look Rock, Tennessee, in 2013) site in the southeastern US using the Aerodyne Aerosol Chemical Speciation Monitor (ACSM) collocated with established air-monitoring network measurements. Seasonal variations in organic aerosol (OA) and inorganic aerosol species are attributed to meteorological conditions as well as anthropogenic and biogenic emissions in this region. The highest concentrations of NR-PM1 were observed during winter and fall seasons at the urban site and during spring and summer at the rural site. Across all seasons and at both sites, NR-PM1 was composed largely of OA (up to 76 %) and sulfate (up to 31 %). Six distinct OA sources were resolved by positive matrix factorization applied to the ACSM organic mass spectral data collected from the two sites over the 1 year of near-continuous measurements at each site: hydrocarbon-like OA (HOA), biomass burning OA (BBOA), semi-volatile oxygenated OA (SV-OOA), low-volatility oxygenated OA (LV-OOA), isoprene-derived epoxydiols (IEPOX) OA (IEPOX-OA) and 91Fac (a factor dominated by a distinct ion at m/z 91 fragment ion previously observed in biogenic influenced areas). LV-OOA was observed throughout the year at both sites and contributed up to 66 % of total OA mass. HOA was observed during the entire year only at the urban site (on average 21 % of OA mass). BBOA (15-33 % of OA mass) was observed during winter and fall, likely dominated by local residential wood burning emission. Although SV-OOA contributes quite significantly ( ˜ 27 %), it was observed only at the urban site during colder seasons. IEPOX-OA was a major component (27-41 %) of OA at both sites, particularly in spring and summer. An ion fragment at m/z 75 is well correlated with the m/z 82 ion associated with the aerosol mass spectrum of IEPOX-derived secondary organic aerosol (SOA). The

  10. Infrared image processing devoted to thermal non-contact characterization-Applications to Non-Destructive Evaluation, Microfluidics and 2D source term distribution for multispectral tomography

    Science.gov (United States)

    Batsale, Jean-Christophe; Pradere, Christophe

    2015-11-01

    The cost of IR cameras is more and more decreasing. Beyond the preliminary calibration step and the global instrumentation, the infrared image processing is then one of the key step for achieving in very broad domains. Generally the IR images are coming from the transient temperature field related to the emission of a black surface in response to an external or internal heating (active IR thermography). The first applications were devoted to the so called thermal Non-Destructive Evaluation methods by considering a thin sample and 1D transient heat diffusion through the sample (transverse diffusion). With simplified assumptions related to the transverse diffusion, the in-plane diffusion and transport phenomena can be also considered. A general equation can be applied in order to balance the heat transfer at the pixel scale or between groups of pixels in order to estimate several fields of thermophysical properties (heterogeneous field of in-plane diffusivity, flow distributions, source terms). There is a lot of possible strategies to process the space and time distributed big amount of data (previous integral transformation of the images, compression, elimination of the non useful areas...), generally based on the necessity to analyse the derivative versus space and time of the temperature field. Several illustrative examples related to the Non-Destructive Evaluation of heterogeneous solids, the thermal characterization of chemical reactions in microfluidic channels and the design of systems for multispectral tomography, will be presented.

  11. Synthesis, characterization, and application of silica supported ionic liquid as catalyst for reductive amination of cyclohexanone with formic acid and triethyl amine as hydrogen source

    Institute of Scientific and Technical Information of China (English)

    Ashif H. Tamboli; Avinash A. Chaugule; Faheem A. Sheikh; Wook-Jin Chung; Hern Kim

    2015-01-01

    A silica supported ionic liquid was synthesized and characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, X-ray diffraction, N2 adsorption-desorption, and thermogravimetric analysis. All these techniques, especially SEM results indicated the presence of well-defined spherical particles having diameters larger than the pristine silica particles, confirming the successful immobilization of the ionic liquid. The prepared silica supported ionic liquid was used in the reductive amination of cyclohexanone under different conditions with different azeo-tropic mixtures of formic acid and triethyl amine as a hydrogen source. The catalyst showed effi-cient catalytic performance and excellent yields of N-cyclohexyl amine derivatives in the range of 58%to 84%at 30 °C. After completion of the reaction, the catalyst was easily recovered by simple filtration and reused for another five cycles without any significant impact on product yields. The obtained catalytic performance indicates that the present catalyst is green, very active, and reusable for the reductive amination of cyclohexanone.

  12. A multidimensional horizontal-loop controlled-source electromagnetic inversion method and its use to characterize heterogeneity in aquiferous fractured crystalline rocks

    Science.gov (United States)

    Sasaki, Yutaka; Meju, Max A.

    2006-07-01

    The controlled-source dual horizontal-loop harmonic electromagnetic (HLEM) profiling method is well suited to the problem of investigating fracture zones in crystalline rocks but there are still limitations in the way that experimental data are currently interpreted-the use of 1-D data inversion leads to inaccurate determination of geological structure. To allow accurate characterization of zones of fractured rock especially underneath heterogeneous overburden, we have developed an efficient 2.5-D regularized inversion method for reconstructing subsurface electrical resistivity distributions from multifrequency HLEM data, with the forward problem solved in 3-D using a staggered-grid finite-difference method. The inversion method is validated using a synthetic example and practical data sets from four borehole sites in a granitic terrain in northeast Brazil. An appraisal of our results for sites with boreholes sited using conventional data analysis procedures shows that we can distinguish between optimally located productive wells in fracture-zone lineaments and those with diminished yields in weathered layer with no major underlying fracture zones. We suggest that 2.5-D inversion can aid in developing better strategies for sustainable groundwater resource development in the basement terrains.

  13. Fissible Deposit Characterization at the Former Oak Ridge K-25 Gaseous Diffusion Plant by {sup 252}CF-Source-Driven Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Hannon, T.F.; Mihalczo, J.T.; Mullens, J.A.; Uckan, T.; Valentine, T.E.; Wyatt, M.S.

    1998-05-01

    Laboratory (ORNL) characterize the two largest deposits with the {sup 252}Cf-source-driven transmission (CFSDT) technique, an active neutron interrogation method developed for use at the Oak Ridge Y-12 Plant to identify nuclear weapons components in containers. The active CFSDT measurement technique uses CFSDT time-of-flight measurements of prompt neutrons and gamma rays from an externally introduced {sup 252}Cf source.

  14. Characterization of Missouri surface waters near point sources of pollution reveals potential novel atmospheric route of exposure for bisphenol A and wastewater hormonal activity pattern

    Science.gov (United States)

    Kassotis, Christopher D.; Alvarez, David A.; Taylor, Julia A.; vom Saal, Frederick S.; Nagel, Susan C.; Tillitt, Donald E.

    2015-01-01

    Surface water contamination by chemical pollutants increasingly threatens water quality around the world. Among the many contaminants found in surface water, there is growing concern regarding endocrine disrupting chemicals, based on their ability to interfere with some aspect of hormone action in exposed organisms, including humans. This study assessed water quality at several sites across Missouri (near wastewater treatment plants and airborne release sites of bisphenol A) based on hormone receptor activation potencies and chemical concentrationspresent in the surface water. We hypothesized that bisphenol A and ethinylestradiol would be greater in water near permitted airborne release sites and wastewater treatment plant inputs, respectively, and that these two compounds would be responsible for the majority of activities in receptor-based assays conducted with water collected near these sites. Concentrations of bisphenol A and ethinylestradiol were compared to observed receptor activities using authentic standards to assess contribution to total activities, and quantitation of a comprehensive set of wastewater compounds was performed to better characterize each site. Bisphenol A concentrations were found to be elevated in surface water near permitted airborne release sites, raising questions that airborne releases of BPA may influence nearby surface water contamination and may represent a previously underestimated source to the environment and potential for human exposure. Estrogen and androgen receptor activities of surface water samples were predictive of wastewater input, although the lower sensitivity of the ethinylestradiol ELISA relative to the very high sensitivity of the bioassay approaches did not allow a direct comparison. Wastewater-influenced sites also had elevated anti-estrogenic and anti-androgenic equivalence, while sites without wastewater discharges exhibited no antagonist activities.

  15. Characterization of a Thermotolerant Phytase Produced by Rhizopus microsporus var. microsporus Biofilm on an Inert Support Using Sugarcane Bagasse as Carbon Source.

    Science.gov (United States)

    Sato, Vanessa Sayuri; Jorge, João Atílio; Guimarães, Luis Henrique Souza

    2016-06-01

    The Rhizopus microsporus var. microsporus biofilm was able to produce increased levels of an extracellular thermotolerant phytase using polyethylene and viscose as an inert support in both modified NBRIP medium and modified Khanna medium containing sugarcane bagasse as the carbon source. The enzyme production was strictly regulated by the phosphorus content with optimal production at 0.5 mM of sodium phytate and KH2PO4. The extracellular phytase, RMPhy1, was purified 4.18-fold with 4.78 % recovery using DEAE-cellulose and CM-cellulose. A single protein band with a molecular mass of 35.4 kDa was obtained when the samples were subjected to 10 % SDS-PAGE. The optimum temperature for activity was 55 °C and the optimum pH was 4.5. R. microsporus var. microsporus phytase exhibited high stability at 30 and 40 °C with a half-life of 115 min at 60 °C. The enzyme activity increased in the presence of Ca (2+) and was inhibited by Zn(2+), arsenate, and sodium phosphate. Phytase demonstrated high substrate specificity for sodium phytate with K m = 0.72 mM and V max = 94.55 U/mg of protein and for p-NPP with K m = 0.04 mM and V max = 106.38 U/mg of protein. The enzyme also hydrolyzed ATP, AMPc, glucose 6-phosphate, glucose 1-phosphate, and UDPG. This is the first report on phytase characterization delivered with biofilm technology. The properties of the enzyme account for its high potential for use in biotechnology and the possibility of application in different industrial sectors as feed in the future. PMID:26906117

  16. Experimental characterization of the Advanced Liquid Hydrogen Cold Neutron Source spectrum of the NBSR reactor at the NIST Center for Neutron Research

    Science.gov (United States)

    Cook, J. C.; Barker, J. G.; Rowe, J. M.; Williams, R. E.; Gagnon, C.; Lindstrom, R. M.; Ibberson, R. M.; Neumann, D. A.

    2015-08-01

    The recent expansion of the National Institute of Standards and Technology (NIST) Center for Neutron Research facility has offered a rare opportunity to perform an accurate measurement of the cold neutron spectrum at the exit of a newly-installed neutron guide. Using a combination of a neutron time-of-flight measurement, a gold foil activation measurement, and Monte Carlo simulation of the neutron guide transmission, we obtain the most reliable experimental characterization of the Advanced Liquid Hydrogen Cold Neutron Source brightness to date. Time-of-flight measurements were performed at three distinct fuel burnup intervals, including one immediately following reactor startup. Prior to the latter measurement, the hydrogen was maintained in a liquefied state for an extended period in an attempt to observe an initial radiation-induced increase of the ortho (o)-hydrogen fraction. Since para (p)-hydrogen has a small scattering cross-section for neutron energies below 15 meV (neutron wavelengths greater than about 2.3 Å), changes in the o- p hydrogen ratio and in the void distribution in the boiling hydrogen influence the spectral distribution. The nature of such changes is simulated with a continuous-energy, Monte Carlo radiation-transport code using 20 K o and p hydrogen scattering kernels and an estimated hydrogen density distribution derived from an analysis of localized heat loads. A comparison of the transport calculations with the mean brightness function resulting from the three measurements suggests an overall o- p ratio of about 17.5(±1) % o- 82.5% p for neutron energies<15 meV, a significantly lower ortho concentration than previously assumed.

  17. QnrS1- and Aac(6’-Ib-cr-producing Escherichia coli among isolates from animals of different sources: susceptibility and genomic characterization

    Directory of Open Access Journals (Sweden)

    Daniela eJones-Dias

    2016-05-01

    Full Text Available Salmonella enterica and Escherichia coli can inhabit humans and animals from multiple origins. These bacteria are often associated with gastroenteritis in animals, being a frequent cause of resistant zoonotic infections. In fact, bacteria from animals can be transmitted to humans through the food chain and direct contact. In this study, we aimed to assess the antibiotic susceptibility of a collection of S. enterica and E. coli recovered from animals of different sources, performing a genomic comparison of the plasmid-mediated quinolone resistance (PMQR-producing isolates detected.Antibiotic susceptibility testing revealed a high number of non wild-type isolates for fluoroquinolones among S. enterica recovered from poultry isolates. In turn, the frequency of non-wild-type E. coli to nalidixic acid and ciprofloxacin was higher in food-producing animals than in companion or zoo animals. Globally, we detected two qnrS1 and two aac(6’-Ib-cr in E. coli isolates recovered from animals of different origins. The genomic characterization of QnrS1-producing E. coli showed high genomic similarity (O86:H12 and ST2297, although they have been recovered from a healthy turtle dove from a Zoo Park, and from a dog showing symptoms of infection. The qnrS1 gene was encoded in a IncN plasmid, also carrying blaTEM-1-containing Tn3. Isolates harboring aac(6’-Ib-cr were detected in two captive bottlenose dolphins, within a time span of two years. The additional antibiotic resistance genes of the two aac(6’-Ib-cr-positive isolates (blaOXA-1, blaTEM-1, blaCTX-M-15, catB3, aac(3-IIa and tetA were enclosed in IncFIA plasmids that differed in a single transposase and 60 single nucleotide variants. The isolates could be assigned to the same genetic sublineage – ST131 fimH30-Rx (O25:H4, confirming clonal spread. PMQR-producing isolates were associated with symptomatic and asymptomatic hosts, which highlight the aptitude of E. coli to act as silent vehicles, allowing

  18. QnrS1- and Aac(6')-Ib-cr-Producing Escherichia coli among Isolates from Animals of Different Sources: Susceptibility and Genomic Characterization.

    Science.gov (United States)

    Jones-Dias, Daniela; Manageiro, Vera; Graça, Rafael; Sampaio, Daniel A; Albuquerque, Teresa; Themudo, Patrícia; Vieira, Luís; Ferreira, Eugénia; Clemente, Lurdes; Caniça, Manuela

    2016-01-01

    Salmonella enterica and Escherichia coli can inhabit humans and animals from multiple origins. These bacteria are often associated with gastroenteritis in animals, being a frequent cause of resistant zoonotic infections. In fact, bacteria from animals can be transmitted to humans through the food chain and direct contact. In this study, we aimed to assess the antibiotic susceptibility of a collection of S. enterica and E. coli recovered from animals of different sources, performing a genomic comparison of the plasmid-mediated quinolone resistance (PMQR)-producing isolates detected. Antibiotic susceptibility testing revealed a high number of non-wild-type isolates for fluoroquinolones among S. enterica recovered from poultry isolates. In turn, the frequency of non-wild-type E. coli to nalidixic acid and ciprofloxacin was higher in food-producing animals than in companion or zoo animals. Globally, we detected two qnrS1 and two aac(6')-Ib-cr in E. coli isolates recovered from animals of different origins. The genomic characterization of QnrS1-producing E. coli showed high genomic similarity (O86:H12 and ST2297), although they have been recovered from a healthy turtle dove from a Zoo Park, and from a dog showing symptoms of infection. The qnrS1 gene was encoded in a IncN plasmid, also carrying bla TEM-1-containing Tn3. Isolates harboring aac(6')-Ib-cr were detected in two captive bottlenose dolphins, within a time span of two years. The additional antibiotic resistance genes of the two aac(6')-Ib-cr-positive isolates (bla OXA-1, bla TEM-1,bla CTX-M-15, catB3, aac(3)-IIa, and tetA) were enclosed in IncFIA plasmids that differed in a single transposase and 60 single nucleotide variants. The isolates could be assigned to the same genetic sublineage-ST131 fimH30-Rx (O25:H4), confirming clonal spread. PMQR-producing isolates were associated with symptomatic and asymptomatic hosts, which highlight the aptitude of E. coli to act as silent vehicles, allowing the accumulation

  19. QnrS1- and Aac(6′)-Ib-cr-Producing Escherichia coli among Isolates from Animals of Different Sources: Susceptibility and Genomic Characterization

    Science.gov (United States)

    Jones-Dias, Daniela; Manageiro, Vera; Graça, Rafael; Sampaio, Daniel A.; Albuquerque, Teresa; Themudo, Patrícia; Vieira, Luís; Ferreira, Eugénia; Clemente, Lurdes; Caniça, Manuela

    2016-01-01

    Salmonella enterica and Escherichia coli can inhabit humans and animals from multiple origins. These bacteria are often associated with gastroenteritis in animals, being a frequent cause of resistant zoonotic infections. In fact, bacteria from animals can be transmitted to humans through the food chain and direct contact. In this study, we aimed to assess the antibiotic susceptibility of a collection of S. enterica and E. coli recovered from animals of different sources, performing a genomic comparison of the plasmid-mediated quinolone resistance (PMQR)-producing isolates detected. Antibiotic susceptibility testing revealed a high number of non-wild-type isolates for fluoroquinolones among S. enterica recovered from poultry isolates. In turn, the frequency of non-wild-type E. coli to nalidixic acid and ciprofloxacin was higher in food-producing animals than in companion or zoo animals. Globally, we detected two qnrS1 and two aac(6′)-Ib-cr in E. coli isolates recovered from animals of different origins. The genomic characterization of QnrS1-producing E. coli showed high genomic similarity (O86:H12 and ST2297), although they have been recovered from a healthy turtle dove from a Zoo Park, and from a dog showing symptoms of infection. The qnrS1 gene was encoded in a IncN plasmid, also carrying blaTEM−1−containing Tn3. Isolates harboring aac(6′)-Ib-cr were detected in two captive bottlenose dolphins, within a time span of two years. The additional antibiotic resistance genes of the two aac(6′)-Ib-cr-positive isolates (blaOXA−1, blaTEM−1,blaCTX−M−15, catB3, aac(3)-IIa, and tetA) were enclosed in IncFIA plasmids that differed in a single transposase and 60 single nucleotide variants. The isolates could be assigned to the same genetic sublineage—ST131 fimH30-Rx (O25:H4), confirming clonal spread. PMQR-producing isolates were associated with symptomatic and asymptomatic hosts, which highlight the aptitude of E. coli to act as silent vehicles, allowing

  20. Source characterization and control technology assessment of methylene chloride emissions from Eastman Kodak Company, Rochester, NY. Final report, July 1988-April 1989

    Energy Technology Data Exchange (ETDEWEB)

    Walata, S.A.; Rehm, R.M.

    1989-07-01

    This report gives results of an assessment of potential control technologies for methylene chloride (also known as dichloromethane or DCM) emission sources at Eastman Kodak Company's Kodak Park facility in Rochester, NY. DCM is a solvent used by Kodak in the manufacture of cellulose triacetate film support. Work has involved: a plant visit where major DCM emission sources were inspected, and evaluation of current and potential control technologies for the DCM emission sources. The report contains information gathered during the plant visit to the Kodak Park facility. Included are emission estimates determined by Kodak of all emission points greater than 8000 lb (3600 kg)/yr DCM, as well as a description of each point observed during the visit. Also included are results of an evaluation of control technologies that might be applied to the major emission sources. A cost analysis of different add-on control devices is provided for four of the uncontrolled emission points.

  1. Integrated characterization of natural attenuation of a PCE plume after thermal remediation of the source zone - incl. dual isotope and microbial techniques

    DEFF Research Database (Denmark)

    Broholm, Mette Martina

    redox, chlorinated ethenes, non-chlorinated degradation products, carbon and chlorine stable isotope composition, as well as specific degraders and their activity was conducted in 2014. The source remediation has, in addition to direct reduction of the concentration level in and flux from the source...... have changed, suggesting an evolution in natural attenuation at significant distance (>1 km down-gradient) from the treated source area. Stable carbon isotopic fractionation revealed significant changes (increase) in the degree of degradation of cDCE in particular both near the source area and > 1 km...... down-gradient which co-inside with the reduction in redox conditions. The findings document a significant increase in cDCE degradation without accumulation of VC. This reduces the risk posed by the contaminant plume to the drinking water resource. This project is unique in the integrated...

  2. Microscopic isolation and characterization of free living amoebae (FLA from surface water sources.in Birjand, the capital city of the South Khorasan

    Directory of Open Access Journals (Sweden)

    Mahmoodreza Behravan

    2015-07-01

    Conclusion: The results indicated that a significant percentage of surface water sources in Birjand city was contaminated with Acanthamoeba spp. It is necessary for physicians, therefore, to take into account the diseases caused by these infectious agents. Besides, local regional health professionals should take into consideration the potential role of surface stagnant water sources in transferring these infectious agents. Placing warning signs in areas contaminated with these infectious agents seems a useful measure.

  3. Synthesis and Characterization of the First Liquid Single Source Precursors for the Deposition of Ternary Chalcopyrite (CuInS2) Thin Film Materials

    Science.gov (United States)

    Banger, Kulbinder K.; Cowen, Jonathan; Hepp, Aloysius

    2002-01-01

    Molecular engineering of ternary single source precursors based on the [{PBu3}2Cu(SR')2In(SR')2] architecture have afforded the first liquid CIS ternary single source precursors (when R = Et, n-Pr), which are suitable for low temperature deposition (liquid phase and reduced stability. X-ray diffraction studies, energy dispersive analyzer (EDS), and scanning electron microscopy (SEM) support the formation of the single-phase chalcopyrite CuInS2 at low temperatures.

  4. Source characterization of sedimentary organic matter using molecular and stable carbon isotopic composition of n-alkanes and fatty acids in sediment core from Lake Dianchi, China

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Jidun [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Shandong Key Laboratory of Eco-Environmental Science for Yellow River Delta, Binzhou University, Binzhou, Shandong Province 256600 (China); Wu, Fengchang, E-mail: wufengchang@163.com [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Xiong, Yongqiang [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Li, Fasheng; Du, Xiaoming; An, Da [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Wang, Lifang [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China)

    2014-03-01

    The distribution and compound-specific carbon isotope ratios of n-alkanes and fatty acids in a sediment core (63 cm) collected from Lake Dianchi were examined to investigate organic matter sources in the eutrophic lake. Fatty acids included free and bound fatty acids. The carbon isotope compositions of individual n-alkanes and fatty acids from Lake Dianchi sediments were determined using gas chromatography/isotope ratio mass spectrometry (GC–IRMS). The δ{sup 13}C values of individual n-alkanes (C{sub 16}–C{sub 31}) varied between − 24.1‰ and − 35.6‰, suggesting a dominance of {sup 13}C-depleted n-alkanes that originated from C{sub 3} plants and lacustrine algae. Fatty acids from the sediment extracts were analyzed for their abundances and carbon isotopic compositions. Molecular and isotopic evidence indicates that most of the short-chain fatty acids from Lake Dianchi sediment extracts are sourced from intense microbial recycling and resynthesis of organic matter. Long-chain free fatty acids are mainly derived from terrestrial sources. However, long-chain bound fatty acids are sourced from a combination of terrestrial organic matter, bacteria and algae, with the contribution from algal sources higher in the hypereutrophic stage. - Highlights: • Long-chain n-alkanes and FFAs are mainly derived from terrestrial sources. • Short-chain n-alkanes and fatty acids are mainly derived from bacterial and/or algal sources. • Long-chain BFAs are mainly derived from algal sources in hypereutrophic lakes.

  5. Source characterization of sedimentary organic matter using molecular and stable carbon isotopic composition of n-alkanes and fatty acids in sediment core from Lake Dianchi, China

    International Nuclear Information System (INIS)

    The distribution and compound-specific carbon isotope ratios of n-alkanes and fatty acids in a sediment core (63 cm) collected from Lake Dianchi were examined to investigate organic matter sources in the eutrophic lake. Fatty acids included free and bound fatty acids. The carbon isotope compositions of individual n-alkanes and fatty acids from Lake Dianchi sediments were determined using gas chromatography/isotope ratio mass spectrometry (GC–IRMS). The δ13C values of individual n-alkanes (C16–C31) varied between − 24.1‰ and − 35.6‰, suggesting a dominance of 13C-depleted n-alkanes that originated from C3 plants and lacustrine algae. Fatty acids from the sediment extracts were analyzed for their abundances and carbon isotopic compositions. Molecular and isotopic evidence indicates that most of the short-chain fatty acids from Lake Dianchi sediment extracts are sourced from intense microbial recycling and resynthesis of organic matter. Long-chain free fatty acids are mainly derived from terrestrial sources. However, long-chain bound fatty acids are sourced from a combination of terrestrial organic matter, bacteria and algae, with the contribution from algal sources higher in the hypereutrophic stage. - Highlights: • Long-chain n-alkanes and FFAs are mainly derived from terrestrial sources. • Short-chain n-alkanes and fatty acids are mainly derived from bacterial and/or algal sources. • Long-chain BFAs are mainly derived from algal sources in hypereutrophic lakes

  6. Waste Characterization Methods

    Energy Technology Data Exchange (ETDEWEB)

    Vigil-Holterman, Luciana R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Naranjo, Felicia Danielle [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-02

    This report discusses ways to classify waste as outlined by LANL. Waste Generators must make a waste determination and characterize regulated waste by appropriate analytical testing or use of acceptable knowledge (AK). Use of AK for characterization requires several source documents. Waste characterization documentation must be accurate, sufficient, and current (i.e., updated); relevant and traceable to the waste stream’s generation, characterization, and management; and not merely a list of information sources.

  7. A comparative study on the analytical utility of atmospheric and low-pressure MALDI sources for the mass spectrometric characterization of peptides.

    Science.gov (United States)

    Moskovets, Eugene; Misharin, Alexander; Laiko, Viktor; Doroshenko, Vladimir

    2016-07-15

    A comparative MS study was conducted on the analytical performance of two matrix-assisted laser desorption/ionization (MALDI) sources that operated at either low pressure (∼1Torr) or at atmospheric pressure. In both cases, the MALDI sources were attached to a linear ion trap mass spectrometer equipped with a two-stage ion funnel. The obtained results indicate that the limits of detection, in the analysis of identical peptide samples, were much lower with the source that was operated slightly below the 1-Torr pressure. In the low-pressure (LP) MALDI source, ion signals were observed at a laser fluence that was considerably lower than the one determining the appearance of ion signals in the atmospheric pressure (AP) MALDI source. When the near-threshold laser fluences were used to record MALDI MS spectra at 1-Torr and 750-Torr pressures, the level of chemical noise at the 1-Torr pressure was much lower compared to that at AP. The dependency of the analyte ion signals on the accelerating field which dragged the ions from the MALDI plate to the MS analyzer are presented for the LP and AP MALDI sources. The study indicates that the laser fluence, background gas pressure, and field accelerating the ions away from a MALDI plate were the main parameters which determined the ion yield, signal-to-noise (S/N) ratios, the fragmentation of the analyte ions, and adduct formation in the LP and AP MALDI MS methods. The presented results can be helpful for a deeper insight into the mechanisms responsible for the ion formation in MALDI.

  8. A comparative study on the analytical utility of atmospheric and low-pressure MALDI sources for the mass spectrometric characterization of peptides.

    Science.gov (United States)

    Moskovets, Eugene; Misharin, Alexander; Laiko, Viktor; Doroshenko, Vladimir

    2016-07-15

    A comparative MS study was conducted on the analytical performance of two matrix-assisted laser desorption/ionization (MALDI) sources that operated at either low pressure (∼1Torr) or at atmospheric pressure. In both cases, the MALDI sources were attached to a linear ion trap mass spectrometer equipped with a two-stage ion funnel. The obtained results indicate that the limits of detection, in the analysis of identical peptide samples, were much lower with the source that was operated slightly below the 1-Torr pressure. In the low-pressure (LP) MALDI source, ion signals were observed at a laser fluence that was considerably lower than the one determining the appearance of ion signals in the atmospheric pressure (AP) MALDI source. When the near-threshold laser fluences were used to record MALDI MS spectra at 1-Torr and 750-Torr pressures, the level of chemical noise at the 1-Torr pressure was much lower compared to that at AP. The dependency of the analyte ion signals on the accelerating field which dragged the ions from the MALDI plate to the MS analyzer are presented for the LP and AP MALDI sources. The study indicates that the laser fluence, background gas pressure, and field accelerating the ions away from a MALDI plate were the main parameters which determined the ion yield, signal-to-noise (S/N) ratios, the fragmentation of the analyte ions, and adduct formation in the LP and AP MALDI MS methods. The presented results can be helpful for a deeper insight into the mechanisms responsible for the ion formation in MALDI. PMID:26899429

  9. Characterization of TLD-100 in powders for dosimetric quality control of 192 Ir sources used in brachytherapy of high dose rate

    International Nuclear Information System (INIS)

    The Secondary Standard Dosimetric at the National Institute of Nuclear Research (ININ) calibrated a lot of powdered TLD-100 (LiF:Mg,Ti) in terms of absorbed dose to water Dw for the energy of: 60Co, 137Cs, X rays of 250 and 50 kVp. Later on, it is carried out an interpolation of the calibration for the energy of the 192Ir. This calibration is part of a dosimetric quality control program, to solve the problems of traceability for the measurements carried out by the users of 192Ir sources employed in the treatments of High Dose Rate Brachytherapy (HDR) at the Mexican Republic. The calibrations of the radiation beams are made with the following protocols: IAEA TRS-398 for the 60Co for Dw, using a secondary standard ionization chamber PTW N30013 calibrated in Dw by the National Research Council (NRC, Canada). AAPM TG-43 for Dw in terms of the strength kerma Sk, calibrating this last one quantity for the 137Cs radioactive source, with a well chamber HDR 1000 PLUS traceable to the University of Wisconsin (US). AAPM TG-61 for X ray of 250 and 50 kVp for Dw start to Ka using field standard a Farmer chamber PTW 30001 traceable to K for the Central Laboratory of Electric Industries (CLEI, France). The calibration curves (CC) they built for the response of the powder TLD: RTLD vs Dw: For the energy of 60Co, 137Cs, X rays of 250 and 50 kVp. Fitting them with the least square method weighed by means of a polynomial of second grade that corrects the supra linearity of the response. iii. Each one of the curves was validated with a test by lack of fitting and for the Anderson Darling normality test, using the software MINITAB in both cases. iv. The sensibility factor (Fs) for each energy corresponds to the slope of the CC, v. The Fs for the two 192Ir sources used are interpolated: one for a Micro Selectron source and the other one a Vari Source source. Finally, a couple of capsules were sent to two hospitals that have the HDR Brachytherapy with sources of 192Ir and that

  10. N-dimensional measurement-device-independent quantum key distribution with N + 1 un-characterized sources: zero quantum-bit-error-rate case.

    Science.gov (United States)

    Hwang, Won-Young; Su, Hong-Yi; Bae, Joonwoo

    2016-01-01

    We study N-dimensional measurement-device-independent quantum-key-distribution protocol where one checking state is used. Only assuming that the checking state is a superposition of other N sources, we show that the protocol is secure in zero quantum-bit-error-rate case, suggesting possibility of the protocol. The method may be applied in other quantum information processing.

  11. N-dimensional measurement-device-independent quantum key distribution with N + 1 un-characterized sources: zero quantum-bit-error-rate case

    Science.gov (United States)

    Hwang, Won-Young; Su, Hong-Yi; Bae, Joonwoo

    2016-07-01

    We study N-dimensional measurement-device-independent quantum-key-distribution protocol where one checking state is used. Only assuming that the checking state is a superposition of other N sources, we show that the protocol is secure in zero quantum-bit-error-rate case, suggesting possibility of the protocol. The method may be applied in other quantum information processing.

  12. Characterizing Lenses and Lensed Stars of High-magnification Single-lens Gravitational Microlensing Events with Lenses Passing over Source Stars

    DEFF Research Database (Denmark)

    Choi, J.-Y.; Shin, I.-G.; Park, S.-Y.;

    2012-01-01

    We present the analysis of the light curves of nine high-magnification single-lens gravitational microlensing events with lenses passing over source stars, including OGLE-2004-BLG-254, MOA-2007-BLG-176, MOA-2007-BLG-233/OGLE-2007-BLG-302, MOA-2009-BLG-174, MOA-2010-BLG-436, MOA-2011-BLG-093, MOA-...

  13. Characterization of a cold cathode Penning ion source for the implantation of noble gases beneath 2D monolayers on metals: Ions and neutrals

    Energy Technology Data Exchange (ETDEWEB)

    Cun, Huanyao, E-mail: hycun1@physik.uzh.ch, E-mail: greber@physik.uzh.ch; Spescha, Annina; Schuler, Adrian; Hengsberger, Matthias; Osterwalder, Jürg; Greber, Thomas, E-mail: hycun1@physik.uzh.ch, E-mail: greber@physik.uzh.ch [Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich (Switzerland)

    2016-03-15

    Argon ion kinetic energy spectra at different discharge voltages (between 480 and 600 V) of a commercial cold cathode ion source IQP10/63 are reported. The high kinetic energy cut-off depends on the discharge voltage and the corresponding plasma potential due to excess positive charges which is found to be about 136 V. Exposure of single layer hexagonal boron nitride on rhodium to the beam of the ion source leads to the formation of nanotents, i.e., stable atomic protrusions. A positive bias voltage is applied to the target sample to block the positive ions produced by the ion source. However, application of a positive bias potential (800 eV), which is higher than the kinetic energy cut-off, still allows the formation of nanotents and its observation with scanning tunneling microscopy. This indicates that the ion source also produces neutral atoms with kinetic energies higher than the penetration threshold across a single layer of hexagonal boron nitride.

  14. Characterization of a neutron source of {sup 239}PuBe; Caracterizacion de una fuente de neutrones de {sup 239}PuBe

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez V, R.; Chacon R, A.; Hernandez D, V. M.; Mercado, G. A.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Ramirez G, J. [Instituto Nacional de Estadistica Geografia e Informatica, Direccion General de Innovacion y Tecnologia de Informacion, Av. Heroes de Nacozari Sur 2301, Fracc. Jardines del Parque, 20276 Aguascalientes (Mexico)], e-mail: ruben_zac@yahoo.com

    2009-10-15

    The spectrum equivalent dose and environmental equivalent dose f a {sup 239}PuBe source have been determined. The appropriate handling of a neutron source depends on the knowledge of its characteristics, such as its energy distribution, total rate of flowing and dosimetric magnitudes. In many facilities have not spectrometer that allows to determine the spectrum and then area monitors are used that give a dosimetric magnitude starting from measuring the flowing rate and the use of conversion factors, however this procedure has many limitations and it is preferable to measure the spectra and starting from this information the interest dosimetric magnitudes are calculated. In this work a Bonner sphere spectrometer has been used with a {sup 6}LiI(Eu) scintillator obtaining the count rates that produce, to a distance of 100 cm, a {sup 239}PuBe source of 1.85E(11) Bq. The spectrum was reconstructed starting from the count rates using BUNKIUT code and response matrix UTA4. With the spectrum information was calculated the source intensity, total flow, energy average, equivalent dose rate, environmental equivalent dose rate, equivalent dose coefficient and environmental equivalent dose coefficient. By means of two area monitors for neutrons, Eberline ASP-1 and LB 6411 of Berthold the equivalent dose and environmental equivalent dose were measured. The determinate values were compared with those reported in literature and it found that are coincident inside 17%. (Author)

  15. Performance Characterization and Validation of Saliva as an Alternative Specimen Source for Detecting Hereditary Breast Cancer Mutations by Next Generation Sequencing

    Science.gov (United States)

    Nahire, Rahul

    2016-01-01

    Identification of pathogenic germline mutations by next generation sequencing is a widely accepted tool for predicting the risk of hereditary cancer development. Blood is the most common source of DNA for such tests. However, blood as a sample type has many drawbacks, including the invasive collection method, poor sample stability, and a relatively high cost of collection. Therefore, in the current study we have assessed the suitability of saliva as an alternative source of genomic DNA for the identification of germline mutations in the BRCA1/2 genes by next generation sequencing (NGS). Our results show that all of the samples yielded DNA concentrations sufficient for library preparation. The concentrations of the final libraries, which were generated by PCR using target specific primers, fall into the expected range with no notable difference between libraries generated from DNA derived from saliva or blood. Quality parameters indicate that sequencing performance is comparable across sample source. An average of (98 ± 0.02)% variant calling concordance was obtained between the two specimen sources. Our data recommends saliva as a potential alternative for detecting germline mutation by next generation sequencing.

  16. The functional potential of microbial communities in hydraulic fracturing source water and produced water from natural gas extraction characterized by metagenomic sequencing.

    Directory of Open Access Journals (Sweden)

    Arvind Murali Mohan

    Full Text Available Microbial activity in produced water from hydraulic fracturing operations can lead to undesired environmental impacts and increase gas production costs. However, the metabolic profile of these microbial communities is not well understood. Here, for the first time, we present results from a shotgun metagenome of microbial communities in both hydraulic fracturing source water and wastewater produced by hydraulic fracturing. Taxonomic analyses showed an increase in anaerobic/facultative anaerobic classes related to Clostridia, Gammaproteobacteria, Bacteroidia and Epsilonproteobacteria in produced water as compared to predominantly aerobic Alphaproteobacteria in the fracturing source water. The metabolic profile revealed a relative increase in genes responsible for carbohydrate metabolism, respiration, sporulation and dormancy, iron acquisition and metabolism, stress response and sulfur metabolism in the produced water samples. These results suggest that microbial communities in produced water have an increased genetic ability to handle stress, which has significant implications for produced water management, such as disinfection.

  17. Seafloor sound-speed profile characterization with non-parallel layering by the image source method: Application to CLUTTER'09 campaign data.

    Science.gov (United States)

    Pinson, Samuel; Holland, Charles W

    2016-08-01

    The image source method was originally developed to estimate sediment sound speed as a function of depth assuming plane-layered sediments. Recently, the technique was extended to treat dipping, i.e., non-parallel layers and was tested using synthetic data. Here, the technique is applied to measured reflection data with dipping layers and mud volcanoes. The data were collected with an autonomous underwater vehicle towing a source (1600-3500 Hz) and a horizontal array of hydrophones. Data were collected every 3 m criss-crossing an area about 1 km(2). The results provide a combination of two-dimensional sections of the sediment sound-speeds plotted in a three-dimensional picture.

  18. Characterization of the Oum Er Rbia (Morocco) high basin karstic water sources by using solid state nuclear track detectors and radon as a natural tracer.

    Science.gov (United States)

    Khalil, N; Misdaq, M A; Berrazzouk, S; Mania, J

    2002-06-01

    Uranium and thorium contents as well as radon alpha-activities per unit volume were evaluated inside different water samples by using a method based on calculating the CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs) detection efficiencies for the emitted alpha-particles and measuring the resulting track density rates. The validity of the SSNTD technique utilized was checked by analysing uranyl nitrate (UO2(NO3)26H2O) standard solutions. A relationship between water radon concentration and water transmission of different water sources belonging to two regions of the Middle Atlas (Morocco) water reservoir was found. The influence of the water flow rate as well as the permeability and fracture system of the host rocks of the sources studied was investigated.

  19. The Functional Potential of Microbial Communities in Hydraulic Fracturing Source Water and Produced Water from Natural Gas Extraction Characterized by Metagenomic Sequencing

    OpenAIRE

    Arvind Murali Mohan; Bibby, Kyle J.; Daniel Lipus; Richard W Hammack; Gregory, Kelvin B.

    2014-01-01

    Microbial activity in produced water from hydraulic fracturing operations can lead to undesired environmental impacts and increase gas production costs. However, the metabolic profile of these microbial communities is not well understood. Here, for the first time, we present results from a shotgun metagenome of microbial communities in both hydraulic fracturing source water and wastewater produced by hydraulic fracturing. Taxonomic analyses showed an increase in anaerobic/facultative anaerobi...

  20. MORPHOLOGICAL CHARACTERIZATION OF AERIAL HYPHAE AND SIMULATION GROWTH OF Fusarium solani UNDER DIFFERENT CARBON SOURCE FOR APPLICATION IN THE HYDROPHOBIC VOCs BIOFILTRATION

    OpenAIRE

    Vergara-Fernández, A.; Hernández, S; J. San Martín-Davison; Revah, S.

    2011-01-01

    This work presents the eect of dierent carbon sources (glycerol, 1-hexanol and n-hexane) over the morphology of the aerial hyphae of the filamentous fungus Fusarium solani for its application in the biofiltration of volatile organic compounds (VOCs). A mathematical model was developed and further verified that combines microscopic and macroscopic parameters describing the mycelial fungal growth. Image analysis of microcultures and culture in agar dishes was performed to determine the morpholo...

  1. Characterization of anthropogenic and natural sources of acid rock drainage at the Cinnamon Gulch abandoned mine land inventory site, Summit County, Colorado

    Science.gov (United States)

    Bird, D.A.

    2003-01-01

    Colorado's Cinnamon Gulch releases acid rock drainage (ARD) from anthropogenic and natural sources. In 2001, the total discharge from Cinnamon Gulch was measured at 1.02 cfs (29 L/s) at base flow and 4.3 cfs (122 L/s) at high flow (spring runoff). At base flow, natural sources account for 98% of the discharge from the watershed, and about 96% of the chemical loading. At high flow, natural sources contribute 96% of discharge and 92 to 95% of chemical loading. The pH is acidic throughout the Cinnamon Gulch watershed, ranging from 2.9 to 5.4. At baseflow, nearly all of the trace metals analyzed in the 18 samples exceeded state hardness-dependent water quality standards for aquatic life. Maximum dissolved concentrations of selected constituents included 16 mg/ L aluminum, 15 mg/L manganese, 40 mg/L iron, 2 mg/L copper, 560 ??g/L lead, 8.4 mg/L zinc, and 300 mg/L sulfate. Average dissolved concentrations of selected metals at baseflow were 5.5 mg/L aluminum, 5.5 mg/L manganese, 14 ??g/L cadmium, 260 ??g/L copper, 82 ??g/L lead, and 2.8 mg/L zinc.

  2. Characterization and source apportionment of aerosol light extinction with a coupled model of CMB-IMPROVE in Hangzhou, Yangtze River Delta of China

    Science.gov (United States)

    Wang, Jiao; Zhang, Yu-fen; Feng, Yin-chang; Zheng, Xian-jue; Jiao, Li; Hong, Sheng-mao; Shen, Jian-dong; Zhu, Tan; Ding, Jing; Zhang, Qi

    2016-09-01

    To investigate the characteristics and sources of aerosol light extinction in the Yangtze River Delta of China, a campaign was carried out in Hangzhou from December 2013 to November 2014. Hourly data for air pollutants including PM2.5, SO2, NO2, O3 and CO, and aerosol optical properties including aerosol scattering coefficient and aerosol absorbing coefficient was obtained in the environmental air quality automatic monitoring station. Meteorological parameters were measured synchronously in the automated meteorology monitoring station. Additionally, around seven sets of ambient PM2.5 samples per month were collected and analyzed during the campaign. The annual mean aerosol scattering coefficient, aerosol absorbing coefficient and aerosol single scattering albedo measured in this study was 514 ± 284 Mm- 1, 35 ± 20 Mm- 1 and 94% respectively. The aerosol extinction coefficient reconstructed using the modified IMPROVE (Interagency Monitoring of Protected Visual Environment) formula was compared to the measured extinction coefficient. Better correlations could be found between the measured and reconstructed extinction coefficient when RH was under 90%. A coupled model of CMB (chemical mass balance) and modified IMPROVE was used to apportion the sources of aerosol light extinction in Hangzhou. Vehicle exhaust, secondary nitrate and secondary sulfate were identified as the most significant sources for aerosol light extinction, accounted for 30.2%, 24.1% and 15.8% respectively.

  3. Process characterization and influence of alternative carbon sources and carbon-to-nitrogen ratio on organic acid production by Aspergillus oryzae DSM1863.

    Science.gov (United States)

    Ochsenreither, Katrin; Fischer, Christian; Neumann, Anke; Syldatk, Christoph

    2014-06-01

    L-Malic acid and fumaric acid are C4 dicarboxylic organic acids and considered as promising chemical building blocks. They can be applied as food preservatives and acidulants in rust removal and as polymerization starter units. Molds of the genus Aspergillus are able to produce malic acid in large quantities from glucose and other carbon sources. In order to enhance the production potential of Aspergillus oryzae DSM 1863, production and consumption rates in an established bioreactor batch-process based on glucose were determined. At 35 °C, up to 42 g/L malic acid was produced in a 168-h batch process with fumaric acid as a by-product. In prolonged shaking flask experiments (353 h), the suitability of the alternative carbon sources xylose and glycerol at a carbon-to-nitrogen (C/N) ratio of 200:1 and the influence of different C/N ratios in glucose cultivations were tested. When using glucose, 58.2 g/L malic acid and 4.2 g/L fumaric acid were produced. When applying xylose or glycerol, both organic acids are produced but the formation of malic acid decreased to 45.4 and 39.4 g/L, respectively. Whereas the fumaric acid concentration was not significantly altered when cultivating with xylose (4.5 g/L), it is clearly enhanced by using glycerol (9.3 g/L). When using glucose as a carbon source, an increase or decrease of the C/N ratio did not influence malic acid production but had an enormous influence on fumaric acid production. The highest fumaric acid concentrations were determined at the highest C/N ratio (300:1, 8.44 g/L) and lowest at the lowest C/N ratio (100:1, 0.7 g/L).

  4. Characterizing relationships among fecal indicator bacteria, microbial source tracking markers, and associated waterborne pathogen occurrence in stream water and sediments in a mixed land use watershed.

    Science.gov (United States)

    Bradshaw, J Kenneth; Snyder, Blake J; Oladeinde, Adelumola; Spidle, David; Berrang, Mark E; Meinersmann, Richard J; Oakley, Brian; Sidle, Roy C; Sullivan, Kathleen; Molina, Marirosa

    2016-09-15

    Bed sediments of streams and rivers may store high concentrations of fecal indicator bacteria (FIB) and pathogens. Due to resuspension events, these contaminants can be mobilized into the water column and affect overall water quality. Other bacterial indicators such as microbial source tracking (MST) markers, developed to determine potential sources of fecal contamination, can also be resuspended from bed sediments. The primary objective of this study was to predict occurrence of waterborne pathogens in water and streambed sediments using a simple statistical model that includes traditionally measured FIB, environmental parameters and source allocation, using MST markers as predictor variables. Synoptic sampling events were conducted during baseflow conditions downstream from agricultural (AG), forested (FORS), and wastewater pollution control plant (WPCP) land uses. Concentrations of FIB and MST markers were measured in water and sediments, along with occurrences of the enteric pathogens Campylobacter, Listeria and Salmonella, and the virulence gene that carries Shiga toxin, stx2. Pathogens were detected in water more often than in underlying sediments. Shiga toxin was significantly related to land use, with concentrations of the ruminant marker selected as an independent variable that could correctly classify 76% and 64% of observed Shiga toxin occurrences in water and sediment, respectively. FIB concentrations and water quality parameters were also selected as independent variables that correctly classified Shiga toxin occurrences in water and sediment (54%-87%), and Salmonella occurrences in water (96%). Relationships between pathogens and indicator variables were generally inconsistent and no single indicator adequately described occurrence of all pathogens. Because of inconsistent relationships between individual pathogens and FIB/MST markers, incorporating a combination of FIB, water quality measurements, and MST markers may be the best way to assess

  5. Characterization of helium/argon working gas systems in a radiofrequency glow discharge atomic emission source. Part I: Optical emission, sputtering and electrical characteristics

    Science.gov (United States)

    Christopher, Steven J.; Hartenstein, Matthew L.; Marcus, R. Kenneth; Belkin, Mikhail; Caruso, Joseph A.

    1998-08-01

    Studies are performed to determine the influence of discharge gas composition (helium/argon working gas mixtures) on the analyte emission signal intensities, sputtering rates, and DC-bias characteristics of an analytical radiofrequency glow discharge atomic emission spectroscopy (RF-GD-AES) source. As the partial pressure of He is increased from 0 to 15 torr, increased emission intensity is observed for a range of bulk and trace elements in NIST 1250 SRM (low alloy steel), regardless of the base pressure of Ar in the source (5 and 9 torr). In contrast to increases in analyte emission intensity of up to 300%, counterindicative decreases in the sputtering rates on the order of about 30-50% are observed. The magnitude of these effects depends on both the partial pressure of helium introduced to the source and the total pressure of the He and Ar gases. Use of relative emission yield (REY) to normalize changes in emission intensity to sputtering rates indicates that excitation efficiencies increase under these conditions. Increases in average electron energy and temperature appear to control this response. Decreases in both analyte emission intensities and sputter rates occur with increasing He partial pressure when the total pressure in the cell remains fixed (11 torr in these studies). Emission yields for the fixed pressure, mixed gas plasmas decrease as the partial pressure of He (He/Ar ratio) in the RF-GD source increases. In this case, decreases in electron number densities appear to dictate the lower REYs. Measurement of DC-bias values at the sample surface provide understanding with respect to the observed changes in sputtering rates as well as suggest the origins of changes in plasma electron energetics. Use of a diamond stylus profilometer provides both the quantitative sputter rate information as well as qualitative insights into the use of mixed gas plasmas for enhanced depth profiling capabilities. The analyte emission characteristics of these mixed gas

  6. Facile preparation of PbS nanostructures and PbS/f-CNT nanocomposites using xanthate as sulfur source: Thermal and optical characterization

    Energy Technology Data Exchange (ETDEWEB)

    Golabi, Parisa; Akbarzadeh, Raziyeh; Dehghani, Hossein, E-mail: dehghani@kashanu.ac.ir

    2015-10-25

    PbS nanostructures with different morphologies were fabricated using a new sulfur source through a facile and low cost hydro(solvo)thermal method. The influence of different reaction factors such as sulfur source, temperature, reactant, solvent and surfactant on the size and morphology of the obtained PbS particles were investigated. Beside, a simple hydrothermal process at low temperature (60 °C) for little time (4 h), has been used for preparation of PbS nanoparticles (NPs)/functionalized multi wall carbon nanotubes (f-MWCNTs) nanocomposite. The as-prepared nanocomposite possesses excellent thermal and optical properties. Thermal stability increases by depositing PbS nanoparticles on the surface of CNT. The structure, morphology, thermal and optical properties of the as-prepared nanocompounds were studied by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Scanning electron microscope (SEM), Energy-dispersive X-ray spectroscopy, Thermogravimetric analysis (TGA), Pl spectra and UV–Vis absorption spectra. Photoluminescence spectra of PbS NPs and nanocomposite are consist of two emission peaks which centered at around 402 and 423 nm, when excited at 350 nm. It was noteworthy that the blue luminescence intensity over PbS/f-CNT nanocomposite is very lower than that of pure PbS NPs. Remarkable blue-shift from bulk material was observed on the PbS nanoparticles using UV–Vis spectrum. Furthermore, possible growth mechanism of PbS nanostructures is presented. - Graphical abstract: PbS nanostructures with different morphologies were fabricated using xanthate as sulfide source. Also, PbS/f-CNT nanocomposites were synthesized by simple hydrothermal process at low temperature (60 °C) for little time (4 h). - Highlights: • Sodium tert-butyl xanthate was used as sulfur source for synthesis of PbS. • Pb(CH{sub 3}COO){sub 2}·3H{sub 2}O salt was used for synthesis of PbS. • PbS/CNT nanocomposite was synthesized in deionized water for 4 h at 60

  7. HOTSPUR progress report: neutron source spectrum characterization, and 6Li(n,xα) and 7Li(n,xα) cross section determination

    International Nuclear Information System (INIS)

    As a prerequisite to high accuracy measurements involving the bulk configuration of 6LiD we must have a good grasp of the details of the RTNS-I neutron source energy spectrum. Experiments to this end involving neutron yield vs deuteron energy, ratios of foil activation of selected elements, and pulse height distributions of a Si surface barrier detector are described. With this knowledge, the 4He-production cross sections for 6Li and 7Li are found experimentally to be 0.512b and 0.336b, respectively, at anti E/sub N/ = 15.0 MeV in free-field geometry. 14 references

  8. Characterization and source apportionment of atmospheric organic and elemental carbon during fall and winter of 2003 in Xi'an, China

    OpenAIRE

    Cao, J. J.; J. C. Chow; Lee, S. C.; Y. Li; Chen, S. W.; An, Z. S.; Fung, K.; J. G. Watson; Zhu, C. S.; Liu, S X

    2005-01-01

    Continuous observation of atmospheric organic and elemental carbon (OC, EC) were conducted at Xi'an during high pollution seasons from September 2003 to February 2004. PM2.5 samples were collected on pre-fired quartz-fiber filters with battery-powered mini-volume samplers every day and PM10 samples were collected every third days. Three types of source samples (i.e., coal-combustion, motor vehicle exhaust, and biomass burning) were also colle...

  9. A meta-analytic approach for characterizing the within-worker and between-worker sources of variation in occupational exposure.

    Science.gov (United States)

    Symanski, Elaine; Maberti, Silvia; Chan, Wenyaw

    2006-06-01

    While many studies have quantified the sources of variation in exposure to workplace contaminants for individual groups of workers, patterns of exposure variability have not been investigated since a comprehensive evaluation was carried out over 10 years ago. Therefore, a systematic review of the literature was conducted to identify studies that applied the one-way random-effects model to describe exposure profiles of groups of workers classified on the basis of the kind of work performed and where it was performed. Quantitative estimates of the sources of variation in exposure along with information related to the workplace, contaminant and sampling strategy were compiled. For subsets of the data, based upon the classification scheme used to group workers, weighted empirical cumulative distribution functions were constructed and compared using the non-parametric Kolomogorov-Smirnov two-sample test. Further stratifications evaluated differences by industry, agent and characteristics of the sampling strategy. The review identified nearly 60 studies that examined the within-worker and between-worker sources of variation in exposure to workplace contaminants. In pooling results across studies, the between-worker variability increased as workers were aggregated across jobs and locations. The within-worker variability for an occupational group of workers was generally larger than the between-worker variability, although the differences in the variation in exposures across work shifts relative to the variation among workers' mean exposure levels diminished as groups were combined across jobs and locations. On average, gaseous exposures were more homogeneous than exposures to aerosols or dermal agents as were exposures in the chemical industry compared with the non-chemical industry. The design of sampling strategies also plays an important role with greater variability among groups of workers who were sampled randomly rather than systematically; in addition, differences

  10. Characterization of PM2.5/PM2.5-10 and source tracking in the juncture belt between urban and rural areas of Beijing

    Institute of Scientific and Technical Information of China (English)

    WANG HaiLin; ZHOU YuMin; ZHUANG YaHui; WANG XiaoKe; HAO ZhengPing

    2009-01-01

    Coarse (PM2.5-10) and fine (PM2.5) atmospheric particulate samples were collected in summer and winter during 2005-2007 in the juncture belt between urban and rural areas of Beijing. Elements, ions, organic/elemental carbon (OC/EC) and polynuclear aromatic hydrocarbons (PAHs) were determined to obtain some latest information about the particulate pollution in the juncture belt of Beijing. Particulate matter levels at this site were high as compared with the levels at other sampling sites in Beijing. Pollution elements, secondary ions and PAHs were enriched in fine particles rather than in coarse particles. An obvious seasonal variation of the chemical composition of PM was observed. Source apportionment results showed that secondary components were the largest mass contributor of PM2.5, accounting for 28%; whereas soil-related sources were the largest contributor of PM2.5-10, explaining about 49% of the total mass. The abnormal levels of soil heavy metals at the electronic waste disassembly site in the upwind villages suggested the potential impact of such activities to the environment.

  11. Characterization of various survey meters through car-borne survey in Java Island as a basis data for searching orphan sources

    International Nuclear Information System (INIS)

    Full text: An assessment of available technical means has been performed to select suitable instruments to be used in car borne surveys for the detection and localization of orphan sources. Criteria used for the selection included (i) that the instrument should be simple to operate, (ii) that it should provide reliable results, and (iii) that little time for processing or transferring raw data from the instrument to a desktop computer (for decision making using statistical methods) is required. Based upon these criteria, four hand-held instruments in the BATAN inventory were selected for further study. Measurements data using these four instruments, taken during a 400 km car-borne survey of western Java, was analyzed. The data was taken both in rainy and clear weather conditions, thus recorded fluctuations from the instrument response (when the vehicle was driven along the same paths in both weather conditions) included variations due washout by the rain of Rn daughters. The data from all instruments was analyzed using various statistical tests to determine the most sensitive instruments (with lowest number of alarm fluctuations) and best statistical analysis technique for finding anomalous radiation levels. Using this data, as well as data from taken during controlled field measurements, it was determined that the best instrument could detect a 7.4 GBq 137Cs source from as far as 145 m away, when traveling in a car at 50 kph. (author)

  12. Finding, characterizing and classifying variable sources in multi-epoch sky surveys: QSOs and RR Lyrae in PS1 3$\\pi$ data

    CERN Document Server

    Hernitschek, Nina; Sesar, Branimir; Rix, Hans-Walter; Hogg, David W; Ivezic, Zeljko; Grebel, Eva K; Bell, Eric F; Martin, Nicolas F; Burgett, W S; Flewelling, H; Hodapp, K W; Kaiser, N; Magnier, E A; Metcalfe, N; Wainscoat, R J; Waters, C

    2015-01-01

    In area and depth, the Pan-STARRS1 (PS1) 3$\\pi$ survey is unique among many-epoch, multi-band surveys and has enormous potential for all-sky identification of variable sources. PS1 has observed the sky typically seven times in each of its five bands ($grizy$) over 3.5 years, but unlike SDSS not simultaneously across the bands. Here we develop a new approach for quantifying statistical properties of non-simultaneous, sparse, multi-color lightcurves through light-curve structure functions, effectively turning PS1 into a $\\sim 35$-epoch survey. We use this approach to estimate variability amplitudes and timescales $(\\omega_r, \\tau)$ for all point-sources brighter than $r_{\\mathrm{P1}}=21.5$ mag in the survey. With PS1 data on SDSS Stripe 82 as ``ground truth", we use a Random Forest Classifier to identify QSOs and RR Lyrae based on their variability and their mean PS1 and WISE colors. We find that, aside from the Galactic plane, QSO and RR Lyrae samples of purity $\\sim$75\\% and completeness $\\sim$92\\% can be sel...

  13. POTENTIALLY TOXIC ELEMENT CYCLES AND CHARACTERIZATION OF MULTIPLE SOURCES IN THE IRRIGATION DITCHES FROM THE RAVENNA COASTAL PLAIN THROUGH TRACE ELEMENTS AND ISOTOPE GEOCHEMISTRY

    Directory of Open Access Journals (Sweden)

    Livia Vittori Antisari

    2010-04-01

    Full Text Available While monitoring the physico-chemical characteristics, trace elements and O-H-Sr-B isotopic data were obtained in superficial waters from a number of irrigations canals and ditches in the Ravenna coastal plain, in order to highlight the cycling of potentially toxic elements and the different sources of the solutes. Surveys were conducted during March and July 2008, and considered as representative of the waters in winter and summer, respectively. In summer, the water mass balance in the network is mostly controlled by the ingression of freshwaters from the Canale Emiliano Romagnolo (CER. The O-H isotopic data indicated that, in winter, waters are primarily recharged from Apennine catchments and undergo evaporation to different extents.The boron isotopic signature indicates the important role played by the marine component. A major seawater contribution was evidenced in canals close to the coastline; however, the process controlling the origin of dissolved boron is not solely related to direct mixing with sea water but comprises an additional source probably related to water-soil exchanges and boron of marine origin leaching, owing to the prolonged exposure of alluvial sediments to sea water. An additional boron contribution from the agricultural practice was is also evidenced. Calculation based on the conservative behaviour of chloride ions indicated that in canals and ditches not directly connected with the sea up to the 80% of the Sr budget did not originate from seawater, indicating a source from Al-silicate minerals and supporting the hypothesis of significant soil-water interactions and chemical exchanges.The positive correlation between pH and dissolved oxygen in winter waters is likely to reflect CO2 consumption during algal photosynthesis, favouring the in-situ generation of colloidal particles due to the oxidative precipitation of ferric iron oxy-hydroxides and probably small carbonate particles able to adsorb trace metals on their

  14. Characterization of a hybrid target multi-keV x-ray source by a multi-parameter statistical analysis of titanium K-shell emission

    International Nuclear Information System (INIS)

    We studied the titanium K-shell emission spectra from multi-keV x-ray source experiments with hybrid targets on the OMEGA laser facility. Using the collisional-radiative TRANSPEC code, dedicated to K-shell spectroscopy, we reproduced the main features of the detailed spectra measured with the time-resolved MSPEC spectrometer. We developed a general method to infer the Ne, Te and Ti characteristics of the target plasma from the spectral analysis (ratio of integrated Lyman-α to Helium-α in-band emission and the peak amplitude of individual line ratios) of the multi-keV x-ray emission. Finally, these thermodynamic conditions are compared to those calculated independently by the radiation-hydrodynamics transport code FCI2

  15. Characterization of DNAPL Source Zone Arcgitecture in Clay Till and Limestone Bedrock by Integrated Site Investigations with Innovative and Current Techniques

    DEFF Research Database (Denmark)

    Broholm, Mette Martina; Janniche, Gry Sander; Fjordbøge, Annika Sidelmann;

    in limestone. The coring may also have impacted DNAPL in high permeability zones near the borehole, thereby, potentially affecting the use of the NAPL FLUTe. Water-FLUTe multilevel groundwater monitoring and sampling (under two flow conditions) and FACT-FLUTe sampling and analysis provided important...... of DNAPL source zone architecture in clay till and bryozoan limestone bedrock. Surface investigations included Ground Penetrating Radar (GPR ) and seismic reflection and refraction. Investigations in the clay till included membrane interface probing (MIP) with FID, ECD and GC-MS analysis; coring...... in the limestone aquifer included coring with discrete subsampling for quantitative analysis, SudanIV hydrophobic colour test, PID and geologic descriptions; NAPL and FACT FLUTe exposure and discrete FACT subsampling and analysis; FLUTe liner hydraulic conductivity profiling; Water-FLUTe installation...

  16. Characterization of coal-derived hydrocarbons and source-rock potential of coal beds, San Juan Basin, New Mexico and Colorado, U.S.A.

    Science.gov (United States)

    Rice, D.D.; Clayton, J.L.; Pawlewicz, M.J.

    1989-01-01

    Coal beds are considered to be a major source of nonassociated gas in the Rocky Mountain basins of the United States. In the San Juan basin of northwestern New Mexico and southwestern Colorado, significant quantities of natural gas are being produced from coal beds of the Upper Cretaceous Fruitland Formation and from adjacent sandstone reservoirs. Analysis of gas samples from the various gas-producing intervals provided a means of determining their origin and of evaluating coal beds as source rocks. The rank of coal beds in the Fruitland Formation in the central part of the San Juan basin, where major gas production occurs, increases to the northeast and ranges from high-volatile B bituminous coal to medium-volatile bituminous coal (Rm values range from 0.70 to 1.45%). On the basis of chemical, isotopic and coal-rank data, the gases are interpreted to be thermogenic. Gases from the coal beds show little isotopic variation (??13C1 values range -43.6 to -40.5 ppt), are chemically dry (C1/C1-5 values are > 0.99), and contain significant amounts of CO2 (as much as 6%). These gases are interpreted to have resulted from devolatilization of the humic-type bituminous coal that is composed mainly of vitrinite. The primary products of this process are CH4, CO2 and H2O. The coal-generated, methane-rich gas is usually contained in the coal beds of the Fruitland Formation, and has not been expelled and has not migrated into the adjacent sandstone reservoirs. In addition, the coal-bed reservoirs produce a distinctive bicarbonate-type connate water and have higher reservoir pressures than adjacent sandstones. The combination of these factors indicates that coal beds are a closed reservoir system created by the gases, waters, and associated pressures in the micropore coal structure. In contrast, gases produced from overlying sandstones in the Fruitland Formation and underlying Pictured Cliffs Sandstone have a wider range of isotopic values (??13C1 values range from -43.5 to -38

  17. Using multiple continuous fine particle monitors to characterize tobacco, incense, candle, cooking, wood burning, and vehicular sources in indoor, outdoor, and in-transit settings

    Science.gov (United States)

    Ott, Wayne R.; Siegmann, Hans C.

    This study employed two continuous particle monitors operating on different measurement principles to measure concentrations simultaneously from common combustion sources in indoor, outdoor, and in-transit settings. The pair of instruments use (a) photo-charging (PC) operating on the principle ionization of fine particles that responds to surface particulate polycyclic aromatic hydrocarbons (PPAHs), and (b) diffusion charging (DC) calibrated to measure the active surface area of fine particles. The sources studied included: (1) secondhand smoke (cigarettes, cigars, and pipes), (2) incense (stick and cone), (3) candles used as food warmers, (4) cooking (toasting bread and frying meat), (5) fireplaces and ambient wood smoke, and (6) in-vehicle exposures traveling on California arterials and interstate highways. The ratio of the PC to the DC readings, or the PC/DC ratio, was found to be different for major categories of sources. Cooking, burning toast, and using a "canned heat" food warmer gave PC/DC ratios close to zero. Controlled experiments with 10 cigarettes averaged 0.15 ng mm -2 (ranging from 0.11 to 0.19 ng mm -2), which was similar to the PC/DC ratio for a cigar, although a pipe was slightly lower (0.09 ng mm -2). Large incense sticks had PC/DC ratios similar to those of cigarettes and cigars. The PC/DC ratios for ambient wood smoke averaged 0.29 ng mm -2 on 6 dates, or about twice those of cigarettes and cigars, reflecting a higher ratio of PAH to active surface area. The smoke from two artificial logs in a residential fireplace had a PC/DC ratio of 0.33-0.35 ng mm -2. The emissions from candles were found to vary, depending on how the candles were burned. If the candle flickered and generated soot, a higher PC/DC ratio resulted than if the candle burned uniformly in still air. Inserting piece of metal into the candle's flame caused high PPAH emissions with a record PC/DC reading of 1.8 ng mm -2. In-vehicle exposures measured on 43- and 50-min drives on a

  18. Characterization of a hybrid target multi-keV x-ray source by a multi-parameter statistical analysis of titanium K-shell emission

    Science.gov (United States)

    Primout, M.; Babonneau, D.; Jacquet, L.; Gilleron, F.; Peyrusse, O.; Fournier, K. B.; Marrs, R.; May, M. J.; Heeter, R. F.; Wallace, R. J.

    2016-03-01

    We have studied the titanium K-shell emission spectra from multi-keV x-ray source experiments with hybrid targets on the OMEGA laser facility. Using the collisional-radiative TRANSPEC code, dedicated to K-shell spectroscopy, we reproduced the main features of the detailed spectra measured with the time-resolved MSPEC spectrometer. We have developed a general method to infer the Ne, Te and Ti characteristics of the target plasma from the spectral analysis (ratio of integrated Lyman-α to Helium-α in-band emission and the peak amplitude of individual line ratios) of the multi-keV x-ray emission. These thermodynamic conditions are compared to those calculated independently by the radiation-hydrodynamics transport code FCI2.

  19. Natural and anthropogenic impacts on biogeochemical cycle in Yangtze River basin: Source, transformation and fate of dissolved organic matter (DOM) characterized by 3-D fluorescence spectroscopy

    Science.gov (United States)

    Gan, Shuchai; Wu, Ying; Bao, Hongyan; Zhang, Jing

    2013-04-01

    Inland waters play an important role in the global carbon cycle as reactors for DOM cycling, transformation and transportation. With large amounts of terrestrial DOM, the Yangtze River is vital for coastal environment and ecosystem. In the context of climate change, it's critical to evaluate both hydrodynamic conditions and increasing human activities' impacts on biogeochemical cycle of DOM in Yangtze River across different climatic and hydrologic regions which are poorly understood. What's more, the hydrologic condition changes caused by the Three Gorges Dam (TGD, world's largest power station in terms of installed capacity) have recently proven to be a partition factor for fluvial particle. However, it's still an enigma for dissolved matter cycle. To address those issues, this study applies EEMs combined with bulk characteristics, chlorophyll and absorption spectrum in an attempt to assess characteristics and dynamics of DOM in Yangtze River. It's a novel optical approach that could 'see' molecular structure of DOM without the limits of time-consuming and laborious molecular measurements. Combined with parallel factor analysis, 5 individual fluorescent components have been identified: 3 humic-like (H1, H2, H3) and 2 protein-like components (P1, P2). With typical bioavailability and photo-reactivity, these components suggest different sources and dynamics. On the whole, both DOC and the sum of all 5 components (? Fluo) increased remarkably from the upper reach especially to the Three Gorge Dam and thereafter remained constant (R2between DOC and - Fluo: 0.92). The protein-like components (- P) accounted for 1/4 of - Fluo with apparently weak correlations with DOC and chlorophyll, which implied that the DOM is not dominated by autochthonous production, especially for the upper reach with high concentration of total suspended matter. As for Humic-like component, increasing H1 and DOC in the TGD reservoir area implied impacts from human activities there with intercept

  20. Characterization and source apportionment of atmospheric organic and elemental carbon during fall and winter of 2003 in Xi'an, China

    Directory of Open Access Journals (Sweden)

    J. J. Cao

    2005-01-01

    Full Text Available Continuous measurements of atmospheric organic and elemental carbon (OC and EC were taken during the high-pollution fall and winter seasons at Xi'an, Shaanxi Province, China from September 2003 through February 2004. Battery-powered mini-volume samplers collected PM2.5 samples daily and PM10 samples every third day. Samples were also obtained from the plumes of residential coal combustion, motor-vehicle exhaust, and biomass burning sources. These samples were analyzed for OC/EC by thermal/optical reflectance (TOR following the Interagency Monitoring of Protected Visual Environments (IMPROVE protocol. OC and EC levels at Xi'an are higher than most urban cities in Asia. Average PM2.5 OC concentrations in fall and winter were 34.1±18.0 μg m−3 and 61.9±;33.2 μg m−3, respectively; while EC concentrations were 11.3±6.9 μg m−3 and 12.3±5.3 μg m−3, respectively. Most of the OC and EC were in the PM2.5 fraction. OC was strongly correlated (R>0.95 with EC in the autumn and moderately correlated (R=0.81 with EC during winter. Carbonaceous aerosol (OC×1.6+EC accounted for 48.8%±10.1% of the PM2.5 mass during fall and 45.9±7.5% during winter. The average OC/EC ratio was 3.3 in fall and 5.1 in winter, with individual OC/EC ratios nearly always exceeding 2.0. The higher wintertime OC/EC corresponded to increased residential coal combustion for heating. Total carbon (TC was associated with source contributions using absolute principal component analysis (APCA with eight thermally-derived carbon fractions. During fall, 73% of TC was attributed to gasoline engine exhaust, 23% to diesel exhaust, and 4% to biomass burning. During winter, 44% of TC was attributed to gasoline engine exhaust, 44% to coal burning, 9% to biomass burning, and 3% to diesel engine exhaust.

  1. Source tracing of fluvial suspended sediments by magnetic and geochemical particle characterization: example of the Canche watershed (Nord-Pas-de-Calais, France)

    Science.gov (United States)

    Patault, Edouard; Alary, Claire; Franke, Christine; Gauthier, Arnaud; Abriak, Nor-Edine

    2016-04-01

    In France, erosion by water run-off is estimated to 1.5 t ha-1yr-1 and can exceed 10 t ha-1yr-1 in large growing areas, such as the North of France (Nord-Pas-de-Calais). In this region, the Canche watershed (1294 km2) sustains heavy loss of fertile soils. The land use is mainly dominated by arable lands (80%) and in 2013, 104 kt of suspended sediment transited to the estuary. As demonstrated in literature, agricultural soil erosion leads to the gradual disappearance and depletion of fertile soil, which constitute a non-renewable resource at human time scale. Additionally, water erosion can significantly damage the aquatic habitat and can be responsible for the input of nutrients, bacteria, pesticides, heavy metals and radionuclides into surface waters. Conscious of these effects, many programs have emerged in the Nord-Pas-de-Calais to reduce erosion. This study presents a combination of environmental magnetic proxy parameters and geochemical analyses on sediments and suspended particulate matter. The aim is to develop effective tools to trace erosion by water run-off and quantify this process. In order to identify the respective sediment sources in the Canche watershed, sediment trap samples of suspended particulate matter were recovered at key positions along the Canche watershed. The preliminary results show that magnetic concentration (Mrs) shows typical values for the agricultural soils in the region, but these variations in magnetic concentrations and total irons concentrations are not always correlated, which may be explained by the iron speciation. In calculating the so-called S-ratio for each sample we can distinguish changes in magneto-mineralogy (and thus iron speciation) from magnetite-dominated assemblages in the mainstream Canche (naturel background signal) to high-coercivity-dominated assemblages in the tributaries, typical for soil erosion material rich in hematite/goethite. In combination with the element concentrations from ICP analyses, this proxy

  2. Operation performance and granule characterization of upflow anaerobic sludge blanket (UASB) reactor treating wastewater with starch as the sole carbon source.

    Science.gov (United States)

    Lu, Xueqin; Zhen, Guangyin; Estrada, Adriana Ledezma; Chen, Mo; Ni, Jialing; Hojo, Toshimasa; Kubota, Kengo; Li, Yu-You

    2015-03-01

    Long-term performance of a lab-scale UASB reactor treating starch wastewater was investigated under different hydraulic retention times (HRT). Successful start-up could be achieved after 15days' operation. The optimal HRT was 6h with organic loading rate (OLR) 4g COD/Ld at COD concentration 1000mg/L, attaining 81.1-98.7% total COD removal with methane production rate of 0.33L CH4/g CODremoved. Specific methane activity tests demonstrated that methane formation via H2-CO2 and acetate were the principal degradation pathways. Vertical characterizations revealed that main reactions including starch hydrolysis, acidification and methanogenesis occurred at the lower part of reactor ("main reaction zone"); comparatively, at the up converting acetate into methane predominated ("substrate-shortage zone"). Further reducing HRT to 3h caused volatile fatty acids accumulation, sludge floating and performance deterioration. Sludge floating was ascribed to the excess polysaccharides in extracellular polymeric substances (EPS). More efforts are required to overcome sludge floating-related issues. PMID:25617619

  3. Characterization of recharge and flow behaviour of different water sources in Gunung Kidul and its impact on water quality based on hydrochemical and physico-chemical monitoring

    Science.gov (United States)

    Eiche, Elisabeth; Hochschild, Maren; Haryono, Eko; Neumann, Thomas

    2016-09-01

    Karst aquifers are important water resources but highly vulnerable due to their heterogeneous and complex characteristics. Various hydrological aspects (recharge, flow behaviour) have to be known in detail to develop a sustainable concept for water collection, distribution and treatment. In the karst area of Gunung Sewu (Java, Indonesia) such a concept was to be implemented within a German-Indonesian joint IWRM project. The basic hydrogeological conditions and water quality aspects were characterized on a regional scale through hydrochemical monitoring of springs, wells, subsurface and surface rivers. More detailed information about the recharge, flow and storage behaviour was obtained from high resolution monitoring of T, EC and discharge in one large underground river system. The water quality is well below any guideline values with regard to inorganic pollutants during dry season. During rainy season, dissolved Al concentrations are frequently above the Indonesian guideline value. Slow matrix flow is the most important recharge component during dry season, thus assuring the year-round water availability in the subsurface karst. During rainy season, quick infiltration of the surface water is a dominant recharge component. Rapid response of discharge, T and EC to heavy rain suggests the presence of point recharge that feeds a highly karstfied conduit system with fast conduit flow and short transit time of water. The strong variations in discharge and hydrochemistry are particularly challenging for technical water usage and treatment facilities. Piston flow is indicated to be the third important flow component and is induced by heavy rainfall.

  4. Characterization of recharge and flow behaviour of different water sources in Gunung Kidul and its impact on water quality based on hydrochemical and physico-chemical monitoring

    Science.gov (United States)

    Eiche, Elisabeth; Hochschild, Maren; Haryono, Eko; Neumann, Thomas

    2016-06-01

    Karst aquifers are important water resources but highly vulnerable due to their heterogeneous and complex characteristics. Various hydrological aspects (recharge, flow behaviour) have to be known in detail to develop a sustainable concept for water collection, distribution and treatment. In the karst area of Gunung Sewu (Java, Indonesia) such a concept was to be implemented within a German-Indonesian joint IWRM project. The basic hydrogeological conditions and water quality aspects were characterized on a regional scale through hydrochemical monitoring of springs, wells, subsurface and surface rivers. More detailed information about the recharge, flow and storage behaviour was obtained from high resolution monitoring of T, EC and discharge in one large underground river system. The water quality is well below any guideline values with regard to inorganic pollutants during dry season. During rainy season, dissolved Al concentrations are frequently above the Indonesian guideline value. Slow matrix flow is the most important recharge component during dry season, thus assuring the year-round water availability in the subsurface karst. During rainy season, quick infiltration of the surface water is a dominant recharge component. Rapid response of discharge, T and EC to heavy rain suggests the presence of point recharge that feeds a highly karstfied conduit system with fast conduit flow and short transit time of water. The strong variations in discharge and hydrochemistry are particularly challenging for technical water usage and treatment facilities. Piston flow is indicated to be the third important flow component and is induced by heavy rainfall.

  5. Characterization and sources of black carbon in PM(2.5) at a site close to a roadway in Gwangju, Korea, during winter.

    Science.gov (United States)

    Park, Seung Shik; Lee, Kwon-Ho

    2015-10-01

    Continuous measurements of black carbon (BC) concentrations in PM2.5 were conducted using a single-wavelength aethalometer (@880 nm, Magee Sci., AE16) at a site close to a roadway (∼70 m from roadside) in Gwangju, Korea, during winter (December-February) to investigate the characteristics and sources of BC particles. The BC concentrations ranked in the order of January > December > February, probably due to lower boundary layer height, ambient temperature, and wind speed during January. Diurnal patterns in BC and carbon monoxide (CO) levels exhibited peak concentrations during the morning and evening hours coinciding with rush-hour traffic, with a strong correlation (R(2)) ranging from 0.52 (December) to 0.87 (January). It was found that wind speed was an important factor controlling BC concentrations at the site. Very high BC concentrations, up to ∼18.0 μg m(-3), were observed at wind speeds air masses from China, as well as the local emissions. PMID:26344004

  6. Development and characterization of recombinant chromosome substitution lines (RCSLs) using Hordeum vulgare subsp. spontaneum as a source of donor alleles in a Hordeum vulgare subsp. vulgare background.

    Science.gov (United States)

    Matus, I; Corey, A; Filichkin, T; Hayes, P M; Vales, M I; Kling, J; Riera-Lizarazu, O; Sato, K; Powell, W; Waugh, R

    2003-12-01

    The ancestor of barley (Hordeum vulgare subsp. spontaneum) may be a source of novel alleles for crop improvement. We developed a set of recombinant chromosome substitution lines (RCSLs) using an accession of H. vulgare subsp. spontaneum (Caesarea 26-24, from Israel) as the donor and Hordeum vulgare subsp. vulgare 'Harrington' (the North American malting quality standard) as the recurrent parent via two backcrosses to the recurrent parent, followed by six generations of selfing. Here we report (i) the genomic architecture of the RCSLs, as inferred by simple sequence repeat (SSR) markers, and (ii) the effects of H. vulgare subsp. spontaneum genome segment introgressions in terms of three classes of phenotypes: inflorescence yield components, malting quality traits, and domestication traits. Significant differences among the RCSLs were detected for all phenotypes measured. The phenotypic effects of the introgressions were assessed using association analysis, and these were referenced to quantitative trait loci (QTL) reported in the literature. Hordeum vulgare subsp. spontaneum, despite its overall inferior phenotype, contributed some favorable alleles for agronomic and malting quality traits. In most cases, the introgression of the ancestral genome resulted in a loss of desirable phenotypes in the cultivated parent. Although disappointing from a plant breeding perspective, this finding may prove to be a useful tool for gene discovery.

  7. Source Characterization and Tsunami Modeling of Submarine Landslides Along the Yucatán Shelf/Campeche Escarpment, Southern Gulf of Mexico

    Science.gov (United States)

    Chaytor, Jason D.; Geist, Eric L.; Paull, Charles K.; Caress, David W.; Gwiazda, Roberto; Fucugauchi, Jaime Urrutia; Vieyra, Mario Rebolledo

    2016-08-01

    Submarine landslides occurring along the margins of the Gulf of Mexico (GOM) represent a low-likelihood, but potentially damaging source of tsunamis. New multibeam bathymetry coverage reveals that mass wasting is pervasive along the Yucatán Shelf edge with several large composite landslides possibly removing as much as 70 km3 of the Cenozoic sedimentary section in a single event. Using GIS-based analysis, the dimensions of six landslides from the central and northern sections of the Yucatán Shelf/Campeche Escarpment were determined and used as input for preliminary tsunami generation and propagation models. Tsunami modeling is performed to compare the propagation characteristics and distribution of maximum amplitudes throughout the GOM among the different landslide scenarios. Various factors such as landslide geometry, location along the Yucatán Shelf/Campeche Escarpment, and refraction during propagation result in significant variations in the affected part of the Mexican and US Gulf Coasts. In all cases, however, tsunami amplitudes are greatest along the northern Yucatán Peninsula.

  8. Source characterization and tsunami modeling of submarine landslides along the Yucatán Shelf/Campeche Escarpment, southern Gulf of Mexico

    Science.gov (United States)

    Chaytor, Jason D.; Geist, Eric L.; Paull, Charles K.; Caress, David W; Gwiazda, Roberto; Urrutia Fucugauchi, Jaime; Rebolledo Vieyra, Mario

    2016-01-01

    Submarine landslides occurring along the margins of the Gulf of Mexico (GOM) represent a low-likelihood, but potentially damaging source of tsunamis. New multibeam bathymetry coverage reveals that mass wasting is pervasive along the Yucatán Shelf edge with several large composite landslides possibly removing as much as 70 km3 of the Cenozoic sedimentary section in a single event. Using GIS-based analysis, the dimensions of six landslides from the central and northern sections of the Yucatán Shelf/Campeche Escarpment were determined and used as input for preliminary tsunami generation and propagation models. Tsunami modeling is performed to compare the propagation characteristics and distribution of maximum amplitudes throughout the GOM among the different landslide scenarios. Various factors such as landslide geometry, location along the Yucatán Shelf/Campeche Escarpment, and refraction during propagation result in significant variations in the affected part of the Mexican and US Gulf Coasts. In all cases, however, tsunami amplitudes are greatest along the northern Yucatán Peninsula.

  9. Comparative Characterization of Total Flavonol Glycosides and Terpene Lactones at Different Ages, from Different Cultivation Sources and Genders of Ginkgo biloba Leaves

    Directory of Open Access Journals (Sweden)

    Yong Qin

    2012-08-01

    Full Text Available The extract from Ginkgo biloba leaves has become a very popular plant medicine and herbal supplement for its potential benefit in alleviating symptoms associated with peripheral vascular disease, dementia, asthma and tinnitus. Most research on G. biloba leaves focus on the leaves collected in July and August from four to seven year-old trees, however a large number of leaves from fruit cultivars (trees older than 10 years are ignored and become obsolete after fruit harvest season (November. In this paper, we expand the tree age range (from one to 300 years and first comparatively analyze the total flavonol glycosides and terpene lactones at different ages, from different cultivation sources and genders of G. biloba leaves collected in November by using the validated HPLC-ELSD and HPLC-PDA methods. The results show that the contents of total terpene lactones and flavonol glycosides in the leaves of young ginkgo trees are higher than those in old trees, and they are higher in male trees than in female trees. Geographical factors appear to have a significant influence on the contents as well. These results will provide a good basis for the comprehensive utilization of G. biloba leaves, especially the leaves from fruit cultivars.

  10. Synthesis and characterization of RE3+:Al2O3 nanopowders for application in the polymer-based composite light sources

    Science.gov (United States)

    Polis, P.; Jusza, A.; Anders, K.; Jastrzebska, A.; Olszyna, A.; Jureczko, J.; Fabianowski, W.; Kunicki, A.; Piramidowicz, R.

    2012-06-01

    In this work we report the recent results of our investigations on synthesis of RE3+:Al2O3 nanopowders prepared by a method, in which organic compounds are used as a solvent and lanthanide organic derivatives, and discuss structural and luminescent properties of the powders and PMMA-based composites doped with these powders. The set of the Al2O3 nanopowder samples doped with RE3+ ions (where RE = Yb and Er) was manufactured and examined with respect of their structural and optical properties. The first PMMA-based composites doped with In this work we report the recent results of our investigations on synthesis of RE3+:Al2O3 nanopowders prepared by a method, in which organic compounds are used as a solvent and lanthanide organic derivatives, and discuss structural and luminescent properties of the powders and PMMA-based composites doped with these powders. The set of the Al2O3 nanopowder samples doped with RE3+ ions (where RE = Yb and Er) was manufactured and examined with respect of their structural and optical properties. The first PMMA-based composites doped with Al2O3:RE3+ nanopowders have been manufactured and characterized in the context of their mechanical, structural and luminescent properties. The investigations have confirmed applicability of developed synthesis method to manufacturing of optically active nanopowders of reasonably good structural quality and homogeneity, consisting of nanoparticles with average size in the range of several tens of nanometers as well as possibility of developing the active composite material, based on PMMA polymer host.

  11. Characterization of the source distribution of particulate matter and nitrogen oxides in rural and urban areas; Charakterisierung der Quellverteilung von Feinstaub und Stickoxiden in laendlichem und staedtischem Gebiet

    Energy Technology Data Exchange (ETDEWEB)

    Urban, Susanna

    2010-07-01

    . It could be demonstrated that the total background is composed of quantifying fractions of the regional and the urban background. The difference of the current measuring signals and the regional background represents the maximum achievable release potential through traffic related activities for traffic dominated trace substances. Moreover, typical particulate size distributions and VOC-compositions of different contamination scenarios (urban, suburban and rural with biogenic contribution) could be determined. Adequate weather conditions approved the investigation of inversion layers of trace substances by the passing of a mountain when using the ''driving air-lab''. During the measurement campaign in Duesseldorf three characteristic measuring scenarios of a city, arterial streets, side streets and a tunnel, were distinguished. The correlation analysis showed a coemission of particles and nitrogen oxides. Furthermore, a total background concentration-field with street resolution of a residential area was created which reveals that the representativeness of a hypothetical measuring station only reaches a few 100 m. The multiregression analysis with source pattern of different engine systems in variable operating conditions demonstrated that the main contribution of the VOC-emissions derives from gasoline engines in cold start status. To determine the reaching range of an intense line source, measurements on and close to the highway in the area of Juelich were performed. By means of the crossing of a highway bridge the particle size concentrations demonstrate that the sphere of influence of a highway reaches several 100 m depending on the meteorological and orographic conditions. The gas chromatographic analysis and the following pattern analysis of mobile collected filters of a measuring route in the area of Juelich with motorway, highway, urban and rural road parts revealed a diesel soot contribution of more than 40% to total particulate matter

  12. Characterization and source apportionment of atmospheric organic and elemental carbon during fall and winter of 2003 in Xi'an, China

    Directory of Open Access Journals (Sweden)

    J. J. Cao

    2005-06-01

    Full Text Available Continuous observation of atmospheric organic and elemental carbon (OC, EC were conducted at Xi'an during high pollution seasons from September 2003 to February 2004. PM2.5 samples were collected on pre-fired quartz-fiber filters with battery-powered mini-volume samplers every day and PM10 samples were collected every third days. Three types of source samples (i.e., coal-combustion, motor vehicle exhaust, and biomass burning were also collected during ambient sampling period. Ambient and source samples were analyzed for OC and EC by thermal/optical reflectance (TOR following the Interagency Monitoring of Protected Visual Environments (IMPROVE protocol. The average PM2.5 OC concentrations in fall and winter were 34.1±18.0 µg m-3 and 61.9±33.2 µg m-3, respectively, while EC were 11.3±6.9 µg m-3 and 12.3±5.3 µg m-3, respectively. Most of OC and EC were associated with fine particle (PM2.5 mode. The OC and EC levels at Xi'an are higher than most urban cities in Asia. The OC and EC in fall were found to be strongly correlated (R2>0.9, with moderate correlation in winter (R2=0.66. The carbonaceous aerosol accounted for 48.8±10.1% of the PM2.5 during fall and 45.9±7.5% during winter. Average OC/EC ratio was 3.3 in fall and 5.1 in winter with individual OC/EC ratios constantly exceeding 2.0. Elevated OC/EC ratios were found during heating seasons with increased coal combustion. The contribution of secondary organic carbon was not significant during winter. The time series of OC and EC showed periodic variability. Traffic contributes 5 and 7 day peaks in the spectrum, precipitation appears as a 10 day periodicity and biomass burning can be identified as a 24 day periodicity. Total carbon (TC was apportioned by absolute principal component analysis (APCA using the 8 carbon fraction data (OC1, OC2, OC3, OC4, EC1, EC2

  13. Radon as a tracer to characterize the interactions between groundwater and surface water around the ground source heat pump system in riverside area

    Science.gov (United States)

    Kim, Jaeyeon; Lee, Seong-Sun; Lee, Kang-Kun

    2016-04-01

    The interaction characteristics between groundwater and surface water was examined by using Radon-222 at Han River Environmental Research Center (HRERC) in Korea where a geothermal resource using indirect open loop ground source heat pump (GSHP) has been developed. For designing a high efficiency performance of the open loop system in shallow aquifer, the riverside area was selected for great advantage of full capacity of well. From this reason groundwater properties of the study site can be easily influenced by influx of surrounding Han River. Therefore, 12 groundwater wells were used for monitoring radon concentration and groundwater level with fluctuation of river stage from May, 2014 to Apr., 2015. The short term monitoring data showed that the radon concentration was changed in accordance with flow meter data which was reflected well by the river stage fluctuation. The spatial distribution of radon concentration from long term monitoring data was also found to be affected by water level fluctuation by nearby dam activity and seasonal effect such as heavy rainfall and groundwater pumping. The estimated residence time indicates that river flows to the study site change its direction according to the combined effect of river stage and groundwater hydrology. In the linear regression of the values, flow velocities were yielded around 0.04 to 0.25 m/day which were similar to flow meter data. These results reveal that Radon-222 can be used as an appropriate environmental tracer in examining the characteristics of interaction in consideration of fluctuating river flow on operation of GSHP in the riverside area. ACKNOWLEDGEMENT This work was supported by the research project of "Advanced Technology for Groundwater Development and Application in Riversides (Geowater+) in "Water Resources Management Program (code 11 Technology Innovation C05)" of the MOLIT and the KAIA in Korea.

  14. Characterization of contamination, source and degradation of petroleum between upland and paddy fields based on geochemical characteristics and phospholipid fatty acids

    Institute of Scientific and Technical Information of China (English)

    Juan Zhang; Renqing Wang; Xiaoming Du; Fasheng Li; Jiulan Dai

    2012-01-01

    To evaluate contamination caused by petroleum,surface soil samples were collected from both upland and paddy fields along the irrigation canals in the Hunpu wastewater irrigation region in northeast China.N-alkanes,terpanes,steranes,and phospholipid fatty acids (PLFA) in the surface soil samples were analyzed.The aliphatic hydrocarbon concentration was highest in the samples obtained from the upland field near an operational oil well; it was lowest at I-3P where wastewater irrigation promoted the downward movement of hydrocarbons.The Hunpu region was found contaminated by heavy petroleum from oxic lacustrine fresh water or marine deltaic source rocks.Geochemical parameters also indicated significantly heavier contamination and degradation in the upland fields compared with the paddy fields.Principal component analysis based on PLFA showed various microbial communities between petroleum contaminated upland and paddy fields.Gram-negative bacteria indicated by 15:0,3OH 12:0,and 16:1(9) were significantly higher in the paddy fields,whereas Gram-positive bacteria indicated by i16:0 and 18:1(9)c were significantly higher in the upland fields (p < 0.05).These PLFAs were related to petroleum contamination.Poly-unsaturated PLFA (18:2ω6,9; indicative of hydrocarbondegrading bacteria and fungi) was also significantly elevated in the upland fields.This paper recommends more sensitive indicators of contamination and degradation of petroleum in soil.The results also provide guidelines on soil pollution control and remediation in the Hunpu region and other similar regions.

  15. Genotypic Characterization of Escherichia coli O157:H7 Isolates from Different Sources in the North-West Province, South Africa, Using Enterobacterial Repetitive Intergenic Consensus PCR Analysis

    Directory of Open Access Journals (Sweden)

    Collins Njie Ateba

    2014-05-01

    Full Text Available In many developing countries, proper hygiene is not strictly implemented when animals are slaughtered and meat products become contaminated. Contaminated meat may contain Escherichia coli (E. coli O157:H7 that could cause diseases in humans if these food products are consumed undercooked. In the present study, a total of 94 confirmed E. coli O157:H7 isolates were subjected to the enterobacterial repetitive intergenic consensus (ERIC polymerase chain reaction (PCR typing to generate genetic fingerprints. The ERIC fragments were resolved by electrophoresis on 2% (w/v agarose gels. The presence, absence and intensity of band data were obtained, exported to Microsoft Excel (Microsoft Office 2003 and used to generate a data matrix. The unweighted pair group method with arithmetic mean (UPGMA and complete linkage algorithms were used to analyze the percentage of similarity and matrix data. Relationships between the various profiles and/or lanes were expressed as dendrograms. Data from groups of related lanes were compiled and reported on cluster tables. ERIC fragments ranged from one to 15 per isolate, and their sizes varied from 0.25 to 0.771 kb. A large proportion of the isolates produced an ERIC banding pattern with three duplets ranging in sizes from 0.408 to 0.628 kb. Eight major clusters (I–VIII were identified. Overall, the remarkable similarities (72% to 91% between the ERIC profiles for the isolate from animal species and their corresponding food products indicated some form of contamination, which may not exclude those at the level of the abattoirs. These results reveal that ERIC PCR analysis can be reliable in comparing the genetic profiles of E. coli O157:H7 from different sources in the North-West Province of South Africa.

  16. Molecular Cytogenetic Characterization of Wheat-Thinopyrum elongatum Addition, Substitution and Translocation Lines with a Novel Source of Resistance to Wheat Fusarium Head Blight

    Institute of Scientific and Technical Information of China (English)

    Shulan Fu; Zhenling Lv; Bao Qi; Xiang Guo; Jun Li; Bao Liu; Fangpu Han

    2012-01-01

    Thinopyrum elongatum (2n =2x =14,EE),a wild relative of wheat,has been suggested as a potentially novel source of resistance to several major wheat diseases including Fusarium Head Blight (FHB).In this study,a series of wheat (cv.Chinese Spring,CS) substitution and ditelosomic lines,including Th.elongatum additions,were assessed for Type Ⅱ resistance to FHB.Results indicated that the lines containing chromosome 7E of Th.elongatum gave a high level of resistance to FHB,wherein the infection did not spread beyond the inoculated floret.Furthermore,it was determined that the novel resistance gene(s) of 7E was located on the short-arm (7ES) based on sharp difference in FHB resistance between the two 7E ditelosomic lines for each arm.On the other hand,Th.elongatum chromosomes 5E and 6E likely contain gene(s) for susceptibility to FHB because the disease spreads rapidly within the inoculated spikes of these lines.Genomic in situ hybridization (GISH) analysis revealed that the alien chromosomes in the addition and substitution lines were intact,and the lines did not contain discernible genomic aberrations.GISH and multicolor-GISH analyses were further performed on three translocation lines that also showed high levels of resistance to FHB.Lines TA3499 and TA3695 were shown to contain one pair of wheat-Th.elongatum translocated chromosomes involving fragments of 7D plus a segment of the 7E,while line TA3493 was found to contain one pair of wheat-Th.elongatum translocated chromosomes involving the D- and A-genome chromosomes of wheat.Thus,this study has established that the short-arm of chromosome 7E of Th.elongatum harbors gene(s) highly resistant to the spreading of FHB,and chromatin of 7E introgressed into wheat chromosomes largely retained the resistance,implicating the feasibility of using these lines as novel material for breeding FHB-resistant wheat cultivars.

  17. Characterization of the source distribution of particulate matter and nitrogen oxides in rural and urban areas; Charakterisierung der Quellverteilung von Feinstaub und Stickoxiden in laendlichem und staedtischem Gebiet

    Energy Technology Data Exchange (ETDEWEB)

    Urban, Susanna

    2010-07-01

    . It could be demonstrated that the total background is composed of quantifying fractions of the regional and the urban background. The difference of the current measuring signals and the regional background represents the maximum achievable release potential through traffic related activities for traffic dominated trace substances. Moreover, typical particulate size distributions and VOC-compositions of different contamination scenarios (urban, suburban and rural with biogenic contribution) could be determined. Adequate weather conditions approved the investigation of inversion layers of trace substances by the passing of a mountain when using the ''driving air-lab''. During the measurement campaign in Duesseldorf three characteristic measuring scenarios of a city, arterial streets, side streets and a tunnel, were distinguished. The correlation analysis showed a coemission of particles and nitrogen oxides. Furthermore, a total background concentration-field with street resolution of a residential area was created which reveals that the representativeness of a hypothetical measuring station only reaches a few 100 m. The multiregression analysis with source pattern of different engine systems in variable operating conditions demonstrated that the main contribution of the VOC-emissions derives from gasoline engines in cold start status. To determine the reaching range of an intense line source, measurements on and close to the highway in the area of Juelich were performed. By means of the crossing of a highway bridge the particle size concentrations demonstrate that the sphere of influence of a highway reaches several 100 m depending on the meteorological and orographic conditions. The gas chromatographic analysis and the following pattern analysis of mobile collected filters of a measuring route in the area of Juelich with motorway, highway, urban and rural road parts revealed a diesel soot contribution of more than 40% to total particulate matter

  18. Acoustic emission monitoring of tensile testing of corroded and un-corroded clad aluminum 2024-T3 and characterization of effects of corrosion on AE source events and material tensile properties

    Science.gov (United States)

    Okafor, A. Chukwujekwu; Natarajan, Shridhar

    2014-02-01

    Corrosion damage affects structural integrity and deteriorates material properties of aluminum alloys in aircraft structures. Acoustic Emission (AE) is an effective nondestructive evaluation (NDE) technique for monitoring such damages and predicting failure in large structures of an aircraft. For successful interpretation of data from AE monitoring, sources of AE and factors affecting it need to be identified. This paper presents results of AE monitoring of tensile testing of corroded and un-corroded clad Aluminum 2024-T3 test specimens, and characterization of the effects of strain-rate and corrosion damage on material tensile properties and AE source events. Effect of corrosion was studied by inducing corrosion in the test specimens by accelerated corrosion testing in a Q-Fog accelerated corrosion chamber for 12 weeks. Eight (8) masked dog-bone shaped specimens were placed in the accelerated corrosion chamber at the beginning of the test. Two (2) dog-bone shaped specimens were removed from the corrosion chamber after exposure time of 3, 6, 9, and 12 weeks respectively, and subjected to tension testing till specimen failure along with AE monitoring, as well as two (2) reference samples not exposed to corrosion. Material tensile properties (yield strength, ultimate tensile strength, toughness, and elongation) obtained from tension test and AE parameters obtained from AE monitoring were analyzed and characterized. AE parameters increase with increase in exposure period of the specimens in the corrosive environment. Aluminum 2024-T3 is an acoustically silent material during tensile deformation without any damage. Acoustic emission events increase with increase of corrosion damage and with increase in strain rate above a certain value. Thus AE is suitable for structural health monitoring of corrosion damage. Ultimate tensile strength, toughness and elongation values decrease with increase of exposure period in corrosion chamber.

  19. Point Source Extraction with MOPEX

    CERN Document Server

    Marleau, D M F R

    2005-01-01

    MOPEX (MOsaicking and Point source EXtraction) is a package developed at the Spitzer Science Center for astronomical image processing. We report on the point source extraction capabilities of MOPEX. Point source extraction is implemented as a two step process: point source detection and profile fitting. Non-linear matched filtering of input images can be performed optionally to increase the signal-to-noise ratio and improve detection of faint point sources. Point Response Function (PRF) fitting of point sources produces the final point source list which includes the fluxes and improved positions of the point sources, along with other parameters characterizing the fit. Passive and active deblending allows for successful fitting of confused point sources. Aperture photometry can also be computed for every extracted point source for an unlimited number of aperture sizes. PRF is estimated directly from the input images. Implementation of efficient methods of background and noise estimation, and modified Simplex a...

  20. Automated setup for magnetic hysteresis characterization based on a voltage controlled current source with 500 kHz full power bandwidth and 10 A peak-to-peak current.

    Science.gov (United States)

    Calabrese, G; Capineri, L; Granato, M; Frattini, G

    2015-04-01

    This paper describes the design of a system for the characterization of magnetic hysteresis behavior in soft ferrite magnetic cores. The proposed setup can test magnetic materials exciting them with controlled arbitrary magnetic field waveforms, including the capability of providing a DC bias, in a frequency bandwidth up to 500 kHz, with voltages up to 32 V peak-to-peak, and currents up to 10 A peak-to-peak. In order to have an accurate control of the magnetic field waveform, the system is based on a voltage controlled current source. The electronic design is described focusing on closed loop feedback stabilization and passive components choice. The system has real-time hysteretic loop acquisition and visualization. The comparisons between measured hysteresis loops of sample magnetic materials and datasheet available ones are shown. Results showing frequency and thermal behavior of the hysteresis of a test sample prove the system capabilities. Moreover, the B-H loops obtained with a multiple waveforms excitation signal, including DC bias, are reported. The proposal is a low-cost and replicable solution for hysteresis characterization of magnetic materials used in power electronics.

  1. Automated setup for magnetic hysteresis characterization based on a voltage controlled current source with 500 kHz full power bandwidth and 10 A peak-to-peak current

    Energy Technology Data Exchange (ETDEWEB)

    Calabrese, G.; Capineri, L., E-mail: lorenzo.capineri@unifi.it [Dipartimento di Ingegneria dell’Informazione, Università degli Studi di Firenze, Firenze 50139 (Italy); Granato, M.; Frattini, G. [Texas Instruments Italia, Rozzano (MI) 20089 (Italy)

    2015-04-15

    This paper describes the design of a system for the characterization of magnetic hysteresis behavior in soft ferrite magnetic cores. The proposed setup can test magnetic materials exciting them with controlled arbitrary magnetic field waveforms, including the capability of providing a DC bias, in a frequency bandwidth up to 500 kHz, with voltages up to 32 V peak-to-peak, and currents up to 10 A peak-to-peak. In order to have an accurate control of the magnetic field waveform, the system is based on a voltage controlled current source. The electronic design is described focusing on closed loop feedback stabilization and passive components choice. The system has real-time hysteretic loop acquisition and visualization. The comparisons between measured hysteresis loops of sample magnetic materials and datasheet available ones are shown. Results showing frequency and thermal behavior of the hysteresis of a test sample prove the system capabilities. Moreover, the B-H loops obtained with a multiple waveforms excitation signal, including DC bias, are reported. The proposal is a low-cost and replicable solution for hysteresis characterization of magnetic materials used in power electronics.

  2. KARAKTERISASI MALTODEKSTRIN DP 3-9 SERTA KAJIAN POTENSI PENGGUNAANNYA SEBAGAI SUMBER KARBOHIDRAT PADA MINUMAN OLAHRAGA [Characterization of Maltodextrin DP 3-9 and Assesment of Its Potential Application as Carbohydrate Source in Sport Drink

    Directory of Open Access Journals (Sweden)

    Beni Hidayat 1

    2003-04-01

    Full Text Available This research was aimed at characterization of maltodextrin DP 3-9 (produced by enzymatic hydrolysis and membrane separation process as compared to commercial maltodextrin and glucose and assessment of its potential application as carbohydrate source in sport drink. The research showed that application of maltodextrin DP 3-9 had some advantages as compared to glucose with regard to absorption rate that was 2 times longer (60 minutes instead of 30 minutes, osmolality degree that was 5,6 times lower (178 mOsmol/kg as compared to 1000 mOsmol/kg, and relative sweetness degree that was 10 - 11 times lower (6,15-7,20 as compared to 57,00-61,00. However, thie application of maltodekstrin DP 3-9 had limitation which was shown by its viscosity characteristic that was 5,70 -- 6,20% higher (1,29 cSt and 1,37 cSt as compared to 1,22 cSt and 1,29 cSt. When compared to commercial maltodextrin, maltodextrin DP 3-9 is favorable as carbohydrate source in sport drink based on its absorption rate that was more than 2 times faster (60 minutes as compared to more than 120 minutes and storage stability at refrigeration temperature (which was more than 8 weeks, with or without sterilization; with sterilization.

  3. Source Water Protection Contaminant Sources

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Simplified aggregation of potential contaminant sources used for Source Water Assessment and Protection. The data is derived from IDNR, IDALS, and US EPA program...

  4. Positron sources

    International Nuclear Information System (INIS)

    A tentative survey of positron sources is given. Physical processes on which positron generation is based are indicated and analyzed. Explanation of the general features of electromagnetic interactions and nuclear β+ decay makes it possible to predict the yield and emittance for a given optical matching system between the positron source and the accelerator. Some kinds of matching systems commonly used - mainly working with solenoidal field - are studied and the acceptance volume calculated. Such knowledge is helpful in comparing different matching systems. Since for large machines, a significant distance exists between the positron source and the experimental facility, positron emittance has to be preserved during beam transfer over large distances and methods used for that purpose are indicated. Comparison of existing positron sources leads to extrapolation to sources for future linear colliders. Some new ideas associated with these sources are also presented. (orig.)

  5. SERDP munition disposal source characterization pilot study

    Energy Technology Data Exchange (ETDEWEB)

    McCallen, R.C.; Couch, R.G.; Fried, L.E. [and others

    1995-09-01

    The Strategic Environmental Research and Development Program (SERDP) is supporting studies to develop and implement technologies for the safe, efficient, and environmentally sound disposal of obsolete munitions and propellants which are stored at various locations across the country. One proposed disposal technique is the open-air burning or detonation (OB/OD) of this material. Although OB/OD is viewed as an efficient and cost-effective method for reducing the inventory of unwanted munitions and propellants, questions regarding its safety and environmental impacts must be addressed. Since very large amounts of munitions and propellants must be consumed inexpensively in relatively short time periods and with the very restrictive Federal and State regulations on environmental issues, it is clear that traditional OB/OD procedures will not be acceptable and that it is necessary to develop modified or advanced OB/OD technology. The effectiveness and environmental impact of the OB/OD technology must be verified by experimental data and with validated numerical models for acceptance by Federal and State regulators. Specifically, technology must be developed and tested that minimizes toxic bum and detonation products the noise (peak pressure) and destructive effect (impulse) of the explosive blast generation and travel distance of shrapnel, and entrainment of dust. Three explosion attenuation scenarios are analyzed: Contained water, aqueous foams, and wet sand.

  6. Natural proteins: Sources, isolation, characterization and applications

    OpenAIRE

    Nehete, Jitendra Y.; Bhambar, Rajendra S.; Minal R Narkhede; Gawali, Sonali R.

    2013-01-01

    Worldwide, plant protein contributes substantially as a food resource because it contains essential amino acids for meeting human physiological requirements. However, many versatile plant proteins are used as medicinal agents as they are produced by using molecular tools of biotechnology. Proteins can be obtained from plants, animals and microorganism cells. The abundant economical proteins can be obtained from plant seeds. These natural proteins are obtained by isolation procedures depending...

  7. Positron sources

    International Nuclear Information System (INIS)

    A tentative survey of positron sources is given. Physical processes on which positron generation is based are indicated and analyzed. Explanation of the general features of electromagnetic interactions and nuclear β+ decay makes it possible to predict the yield and emittance for a given optical matching system between the positron source and the accelerator. Some kinds of matching systems commonly used - mainly working with solenoidal fields - are studied and the acceptance volume calculated. Such knowledge is helpful in comparing different matching systems. Since for large machines, a significant distance exists between the positron source and the experimental facility, positron emittance has to be preserved during beam transfer over large distances and methods used for that purpose are indicated. Comparison of existing positron sources leads to extrapolation to sources for future linear colliders

  8. International Entrepreneurship and Sourcing

    DEFF Research Database (Denmark)

    Servais, Per; Zucchella, Antonella; Palamera, Giada

    2006-01-01

    This contribution focuses on international sourcing as an entrepreneurial act and aims at demonstrating that it is actually at the core of internationalization processes of small firms, both established and international new ventures. Another issue of this research is to understand how these firms......, characterized typically by scarce financial and managerial resources, can engage in managing international value chains and not only being the passive agent of subcontracting agreements. The breadth of internationals sourcing activities and the nature of the ties established under these agreements...

  9. Light Source

    Science.gov (United States)

    1993-01-01

    Research on food growth for long duration spacecraft has resulted in a light source for growing plants indoors known as Qbeam, a solid state light source consisting of a control unit and lamp. The light source, manufactured by Quantum Devices, Inc., is not very hot, although it generates high intensity radiation. When Ron Ignatius, an industrial partner of WCSAR, realized that terrestrial plant research lighting was not energy efficient enough for space use, he and WCSAR began to experiment with light emitting diodes. A line of LED products was developed, and QDI was formed to market the technology. An LED-based cancer treatment device is currently under development.

  10. Characterization of solid D{sub 2} as a source material for ultra cold neutrons (UCN) and development of a detector concept for the detection of protons from the neutron decay

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Axel Reimer

    2008-12-09

    In the first part of this thesis, properties of the UCN-converter material solid deuterium (sD{sub 2}) are studied. A series of investigations of various sD{sub 2} crystals by means of optical spectroscopy and neutron scattering resulted in: (i) a freezing technique suitable for UCN sources (ii) an efficient method to achieve a high ortho concentration, (iii) a direct way to calculate the UCN production cross-section from the dynamic structure factor S(q, {omega}), (iv) the identification of six excitations responsible for UCN production (v) the interpretation of one excitation at E=12 meV as a multi-phonon process (vi) the discovery of an additional spin-dependent UCN loss mechanism at q=2.1A{sup -1} and E=1.8 meV. A complementary series of experiments was performed at the FRMII, testing the production of UCN with the studied sample preparation after different the characterization mentioned above. Besides establishing a technique for annealing sD{sub 2} crystals to improve the UCN production rate, an additional loss cross section ({sigma}{sub x}=8 barn at 4.5 K indirect proportional to the ortho concentration) was found. Based on these findings, a new conceptual layout of the miniD{sub 2} source was developed. In the second part, the diffuse scattering probability f and the loss probability per wall collision {mu} were measured for differently prepared UCN guides using the storageand the so called two-hole method. Electropolished, rough stainless steel and Al tubes with different coatings at temperature variation and surface conditions were measured. The third part deals with the development of a proton detector for the neutron lifetime experiment PENeLOPE, which is based on gravitational and magnetic UCN storage and counting of the protons from the decay. A concept for a large-area proton detector based on thin scintillation counters operating in cryogenic environment was developed based on simulations and experimental studies. In addition to the characterization

  11. Sourcing Excellence

    DEFF Research Database (Denmark)

    Adeyemi, Oluseyi

    2011-01-01

    for global sourcing strategies in place, improvement opportunities in this area are attractive and as yet largely unrealized. Shifting from a narrow, cost-reduction emphasis with suppliers to an emphasis on globally integrated and coordinated sourcing strategies with well-developed suppliers would improve...... initiatives by developing effective partnerships with suppliers (9). Meanwhile, this is useful in gaining the short term quick win benefits while focussing on the strategies for deriving additional value in the long term. Identifying the barriers, best practices and potential benefits of integrating......Sourcing Excellence is one of the key performance indicators (KPIs) in this world of ever changing sourcing strategies. Manufacturing companies need to access and diagnose the reliability and competencies of existing suppliers in order to coordinate and develop them. This would help in managing...

  12. Global Sourcing

    OpenAIRE

    Stančíková, Katarína

    2013-01-01

    The subject of this bachelor thesis is to examine the Global Sourcing purchasing strategy as an instrument of reducing the acquisition costs of the company. Globalization has brought increased competition and pressure on reduction of purchase prices in all sectors of the world economy. The use of international trade market is currently an integral part of almost every business strategy. The concept of Global Sourcing consists not only in the use of international markets and the acquisition of...

  13. Culture and Global Sourcing

    OpenAIRE

    Kukharskyy, Bohdan; Gorodnichenko, Yuriy; Roland, Gerard

    2015-01-01

    This paper develops a model of global sourcing with culturally dissimilar countries. Production of final goods requires the coordination of decisions between the headquarter of a multinational firm and managers of their component suppliers. Managers of both units are assumed to have strong beliefs about the right course of action and are reluctant to adjust their decisions. We characterize the optimal allocation of decision rights across firms when contracts are incomplete. Our theoretical mo...

  14. Crowd Sourcing.

    Science.gov (United States)

    Baum, Neil

    2016-01-01

    The Internet has contributed new words and slang to our daily vernacular. A few terms, such as tweeting, texting, sexting, blogging, and googling, have become common in most vocabularies and in many languages, and are now included in the dictionary. A new buzzword making the rounds in industry is crowd sourcing, which involves outsourcing an activity, task, or problem by sending it to people or groups outside a business or a practice. Crowd sourcing allows doctors and practices to tap the wisdom of many instead of relying only on the few members of their close-knit group. This article defines "crowd sourcing," offers examples, and explains how to get started with this approach that can increase your ability to finish a task or solve problems that you don't have the time or expertise to accomplish. PMID:27039640

  15. Crowd Sourcing.

    Science.gov (United States)

    Baum, Neil

    2016-01-01

    The Internet has contributed new words and slang to our daily vernacular. A few terms, such as tweeting, texting, sexting, blogging, and googling, have become common in most vocabularies and in many languages, and are now included in the dictionary. A new buzzword making the rounds in industry is crowd sourcing, which involves outsourcing an activity, task, or problem by sending it to people or groups outside a business or a practice. Crowd sourcing allows doctors and practices to tap the wisdom of many instead of relying only on the few members of their close-knit group. This article defines "crowd sourcing," offers examples, and explains how to get started with this approach that can increase your ability to finish a task or solve problems that you don't have the time or expertise to accomplish.

  16. Hydrolytic Amino Acids Employed as a Novel Organic Nitrogen Source for the Preparation of PGPF-Containing Bio-Organic Fertilizer for Plant Growth Promotion and Characterization of Substance Transformation during BOF Production.

    Directory of Open Access Journals (Sweden)

    Fengge Zhang

    Full Text Available Opportunity costs seriously limit the large-scale production of bio-organic fertilizers (BOFs both in China and internationally. This study addresses the utilization of amino acids resulting from the acidic hydrolysis of pig corpses as organic nitrogen sources to increase the density of TrichodermaharzianumT-E5 (a typical plant growth-promoting fungi, PGPF. This results in a novel, economical, highly efficient and environmentally friendly BOF product. Fluorescence excitation-emission matrix (EEM spectroscopy combined with fluorescence regional integration (FRI was employed to monitor compost maturity levels, while pot experiments were utilized to test the effects of this novel BOF on plant growth. An optimization experiment, based on response surface methodologies (RSMs, showed that a maximum T-E5 population (3.72 × 108 ITS copies g-1 was obtained from a mixture of 65.17% cattle manure compost (W/W, 19.33% maggot manure (W/W, 15.50% (V/Whydrolytic amino acid solution and 4.69% (V/W inoculum at 28.7°C after a 14 day secondary solid fermentation. Spectroscopy analysis revealed that the compost transformation process involved the degradation of protein-like substances and the formation of fulvic-like and humic-like substances. FRI parameters (PI, n, PII, n, PIII, n and PV, n were used to characterize the degree of compost maturity. The BOF resulted in significantly higher increased chlorophyll content, shoot length, and shoot and root dry weights of three vegetables (cucumber, tomato and pepper by 9.9%~22.4%, 22.9%~58.5%, 31.0%~84.9%, and 24.2%~34.1%, respectively. In summary, this study presents an operational means of increasing PGPF T-E5 populations in BOF to promote plant growth with a concomitant reduction in production cost. In addition, a BOF compost maturity assessment using fluorescence EEM spectroscopy and FRI ensured its safe field application.

  17. Fracture source

    Directory of Open Access Journals (Sweden)

    2003-07-01

    Full Text Available The fracture properties of many different types of fibers are covered in a timely new book that will prove to be a tremendous source of information and references for researchers in the wide and diverse field of fibers and composites, says Bill Clegg.

  18. Plasma focus neutron source

    International Nuclear Information System (INIS)

    A neutron source not permanently active is obtained from an electric discharge plasma focus (PF) device. A small PF device, a Mather model device, works in the limit of low energy, 100 to 200 J at charging voltage of 20 to 30 kV with a capacitor bank of 160 nF, and a characteristic inductance of 25 to 50 nH. A theoretical model leads us to estimate the optimum values of capacitance, inductance, initial charging voltage and electrode geometry. In this work is presented the design evolution and construction of a first PF neutron source prototype, preliminary measures of current, voltage and temporal evolution of the current with the end of have an electric characterization. This parameters must be optimized with the objective of geeting an emission of 104 to 105 neutrons per pulse when Deuterium is used like filled gas (C.W)

  19. Asynchronous Learning Sources in a High-Tech Organization

    Science.gov (United States)

    Bouhnik, Dan; Giat, Yahel; Sanderovitch, Yafit

    2009-01-01

    Purpose: The purpose of this study is to characterize learning from asynchronous sources among research and development (R&D) personnel. It aims to examine four aspects of asynchronous source learning: employee preferences regarding self-learning; extent of source usage; employee satisfaction with these sources and the effect of the sources on the…

  20. Sources manuscrites

    OpenAIRE

    2014-01-01

    I. SOURCES CONSULTÉES AUX ARCHIVES NATIONALES Série E 1. Minutes d’arrêts du Conseil, arrêts simples en finances 1602 : E 4a, E 4b. 1605 : E 8a, E 8b, E 8c-9a, E 9b, E 9c. 1608 : E 16a, E 16b, E 18a, E 18b, E 19a, E 19b. 1620 : E 63a E 63b, E 64a, E 64b-65a, E 65b. 1689 : E 579a, E 579b, E 580, E 581, E 582, E 583, E 584a, E 584b, E 585a, E 585b, E 586a, E 586b 1750 : E 1260a E 1260b, E 1261a E 1261b, E 1262a, E 1262b, E 1262e, E 1263a, E 1263b, E 1264a, E 1264b, E 1265a, E 1265b, E 1266a, E ...

  1. Dosimetric characterization of the Cobal-60 bebig Co0.A86 source, using Monte Carlo simulation; Caracterizacion dosimetric de la fuentes de cobalto-60 bebig Co0.A86 mediante simulacion Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Almansa Lopez, J.; Guerrero Alcalde, R.; Torres Donaire, J.; Lallena Rojo, A.

    2013-07-01

    They nourish the leading brachytherapy planning systems. The objective of this work is, for the source of Co-60 BEBIG Co0.A86 of HDR, calculating the dosimetry in water and get parameters and functions described in the Protocol TG-43. using PENELOPE and Geant4 simulation codes, previously used for the simulation of sources of brachytherapy, incorporating the recommendations given in the 229 of the AAPM report. (Author)

  2. International Data on Radiological Sources

    Energy Technology Data Exchange (ETDEWEB)

    Martha Finck; Margaret Goldberg

    2010-07-01

    ABSTRACT The mission of radiological dispersal device (RDD) nuclear forensics is to identify the provenance of nuclear and radiological materials used in RDDs and to aid law enforcement in tracking nuclear materials and routes. The application of databases to radiological forensics is to match RDD source material to a source model in the database, provide guidance regarding a possible second device, and aid the FBI by providing a short list of manufacturers and distributors, and ultimately to the last legal owner of the source. The Argonne/Idaho National Laboratory RDD attribution database is a powerful technical tool in radiological forensics. The database (1267 unique vendors) includes all sealed sources and a device registered in the U.S., is complemented by data from the IAEA Catalogue, and is supported by rigorous in-lab characterization of selected sealed sources regarding physical form, radiochemical composition, and age-dating profiles. Close working relationships with global partners in the commercial sealed sources industry provide invaluable technical information and expertise in the development of signature profiles. These profiles are critical to the down-selection of potential candidates in either pre- or post- event RDD attribution. The down-selection process includes a match between an interdicted (or detonated) source and a model in the database linked to one or more manufacturers and distributors.

  3. Bioprocessing of “Hair Waste” by Paecilomyces lilacinus as a Source of a Bleach-Stable, Alkaline, and Thermostable Keratinase with Potential Application as a Laundry Detergent Additive: Characterization and Wash Performance Analysis

    OpenAIRE

    Sebastián F. Cavalitto; Hours, Roque A.; Cavello, Ivana A.

    2012-01-01

    Paecilomyces lilacinus (Thom) Samson LPS 876, a locally isolated fungal strain, was grown on minimal mineral medium containing “hair waste,” a residue from the hair-saving unhairing process, and produced a protease with keratinolytic activity. This enzyme was biochemically characterized. The optimum reaction conditions, determined with a response surface methodology, were 60°C and pH 6.0. It was remarkably stable in a wide range of pHs and temperatures. Addition of Ca2+, Mg2+, or sorbitol was...

  4. 烃源岩生成有机酸过程的高分辨质谱研究%Characterizing thermal evolution of acid species in hydrocarbon source rock by using negative-ion ESI FT-ICR MS

    Institute of Scientific and Technical Information of China (English)

    蒋启贵; 刘鹏; 黎茂稳; 陶国亮

    2014-01-01

    研究石油中有机酸的生成过程对研究储层改造、石油润湿性及页岩油可动性评价具有重要意义。在热压生烃模拟实验基础上,对Ⅲ型烃源岩不同演化阶段生成油中的非烃馏分进行了负离子电喷雾傅立叶变换离子回旋共振质谱分析,研究了烃源岩生成有机酸过程。对样品生成有机酸分析表明,在整个演化过程烃源岩都能生成有机酸,在低演化阶段主要生成脂肪酸,随演化程度的升高,脂肪酸丰度快速减少,芳环酸开始大量生成。随演化程度的增加,芳环上短链取代基发生断裂,并促进了有机酸的缩合,使得生成的有机酸缩合度逐渐提高,高碳数有机酸逐渐减少;烃源岩生成脂肪酸系列中存在偶奇优势,生成的C16、C18脂肪酸存在异常高丰度, C16、C18脂肪酸异常丰度现象可能是污染造成的,是否与烃源岩类型及成熟度有关尚需进一步研究。%The study on the generation process of organic acid species in hydrocarbon source rocks is of a great significance for understanding reservoir alteration, oil wettability, and shale oil removability evaluation. Based on the thermocompression simulation experiment of hydrocarbon generation, the polar species of the expelled oils from a source rock (Type Ⅲ kerogen) at different maturity stages were determined by negative-ion electrospray ionization (ESI) Fourier Transform Ion Cyclotron Mass Spectrometry (ESI FT-ICR MS). The result shows that the organic acid species can be generated during the whole thermal evolution of hydrocarbon source rock. At low maturity levels (early oil window), fatty acids (DBE=1) are the most abundant species. With the increasing maturity, naphthenic acids and aromatic acids become dominant species. At higher maturity levels, most of the acidic species have been thermally cracked and aromatized, thus only the O2 class with short chains and high DBE values (aromatic acids

  5. Tank characterization reference guide

    International Nuclear Information System (INIS)

    Characterization of the Hanford Site high-level waste storage tanks supports safety issue resolution; operations and maintenance requirements; and retrieval, pretreatment, vitrification, and disposal technology development. Technical, historical, and programmatic information about the waste tanks is often scattered among many sources, if it is documented at all. This Tank Characterization Reference Guide, therefore, serves as a common location for much of the generic tank information that is otherwise contained in many documents. The report is intended to be an introduction to the issues and history surrounding the generation, storage, and management of the liquid process wastes, and a presentation of the sampling, analysis, and modeling activities that support the current waste characterization. This report should provide a basis upon which those unfamiliar with the Hanford Site tank farms can start their research

  6. Tank characterization reference guide

    Energy Technology Data Exchange (ETDEWEB)

    De Lorenzo, D.S.; DiCenso, A.T.; Hiller, D.B.; Johnson